From d155df53f31068c3340733d586eb9b3ddfd70fc5 Mon Sep 17 00:00:00 2001 From: Ma Wupeng Date: Fri, 17 Feb 2023 10:56:15 +0800 Subject: x86/mm/pat: clear VM_PAT if copy_p4d_range failed Syzbot reports a warning in untrack_pfn(). Digging into the root we found that this is due to memory allocation failure in pmd_alloc_one. And this failure is produced due to failslab. In copy_page_range(), memory alloaction for pmd failed. During the error handling process in copy_page_range(), mmput() is called to remove all vmas. While untrack_pfn this empty pfn, warning happens. Here's a simplified flow: dup_mm dup_mmap copy_page_range copy_p4d_range copy_pud_range copy_pmd_range pmd_alloc __pmd_alloc pmd_alloc_one page = alloc_pages(gfp, 0); if (!page) return NULL; mmput exit_mmap unmap_vmas unmap_single_vma untrack_pfn follow_phys WARN_ON_ONCE(1); Since this vma is not generate successfully, we can clear flag VM_PAT. In this case, untrack_pfn() will not be called while cleaning this vma. Function untrack_pfn_moved() has also been renamed to fit the new logic. Link: https://lkml.kernel.org/r/20230217025615.1595558-1-mawupeng1@huawei.com Signed-off-by: Ma Wupeng Reported-by: Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Peter Zijlstra Cc: Suresh Siddha Cc: Toshi Kani Signed-off-by: Andrew Morton --- include/linux/pgtable.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index c63cd44777ec..9dc936bc77d1 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1191,9 +1191,10 @@ static inline void untrack_pfn(struct vm_area_struct *vma, } /* - * untrack_pfn_moved is called while mremapping a pfnmap for a new region. + * untrack_pfn_clear is called while mremapping a pfnmap for a new region + * or fails to copy pgtable during duplicate vm area. */ -static inline void untrack_pfn_moved(struct vm_area_struct *vma) +static inline void untrack_pfn_clear(struct vm_area_struct *vma) { } #else @@ -1205,7 +1206,7 @@ extern void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, extern int track_pfn_copy(struct vm_area_struct *vma); extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, unsigned long size, bool mm_wr_locked); -extern void untrack_pfn_moved(struct vm_area_struct *vma); +extern void untrack_pfn_clear(struct vm_area_struct *vma); #endif #ifdef CONFIG_MMU -- cgit v1.2.3 From 9a52b2f32a0942047348b30f866b846da5fcf4e3 Mon Sep 17 00:00:00 2001 From: "T.J. Alumbaugh" Date: Tue, 14 Feb 2023 03:54:44 +0000 Subject: mm: multi-gen LRU: clean up sysfs code This patch cleans up the sysfs code. Specifically, 1. use sysfs_emit(), 2. use __ATTR_RW(), and 3. constify multi-gen LRU struct attribute_group. Link: https://lkml.kernel.org/r/20230214035445.1250139-1-talumbau@google.com Signed-off-by: T.J. Alumbaugh Cc: Yu Zhao Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 2 +- mm/vmscan.c | 22 +++++++++------------- 2 files changed, 10 insertions(+), 14 deletions(-) (limited to 'include') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 9fb1b03b83b2..bf8786d45b31 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1369,7 +1369,7 @@ typedef struct pglist_data { #ifdef CONFIG_LRU_GEN /* kswap mm walk data */ - struct lru_gen_mm_walk mm_walk; + struct lru_gen_mm_walk mm_walk; /* lru_gen_folio list */ struct lru_gen_memcg memcg_lru; #endif diff --git a/mm/vmscan.c b/mm/vmscan.c index 9c1c5e8b24b8..7ac7d1ec13e0 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -5663,14 +5663,14 @@ unlock: * sysfs interface ******************************************************************************/ -static ssize_t show_min_ttl(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +static ssize_t min_ttl_ms_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%u\n", jiffies_to_msecs(READ_ONCE(lru_gen_min_ttl))); + return sysfs_emit(buf, "%u\n", jiffies_to_msecs(READ_ONCE(lru_gen_min_ttl))); } /* see Documentation/admin-guide/mm/multigen_lru.rst for details */ -static ssize_t store_min_ttl(struct kobject *kobj, struct kobj_attribute *attr, - const char *buf, size_t len) +static ssize_t min_ttl_ms_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t len) { unsigned int msecs; @@ -5682,11 +5682,9 @@ static ssize_t store_min_ttl(struct kobject *kobj, struct kobj_attribute *attr, return len; } -static struct kobj_attribute lru_gen_min_ttl_attr = __ATTR( - min_ttl_ms, 0644, show_min_ttl, store_min_ttl -); +static struct kobj_attribute lru_gen_min_ttl_attr = __ATTR_RW(min_ttl_ms); -static ssize_t show_enabled(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +static ssize_t enabled_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { unsigned int caps = 0; @@ -5703,7 +5701,7 @@ static ssize_t show_enabled(struct kobject *kobj, struct kobj_attribute *attr, c } /* see Documentation/admin-guide/mm/multigen_lru.rst for details */ -static ssize_t store_enabled(struct kobject *kobj, struct kobj_attribute *attr, +static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t len) { int i; @@ -5730,9 +5728,7 @@ static ssize_t store_enabled(struct kobject *kobj, struct kobj_attribute *attr, return len; } -static struct kobj_attribute lru_gen_enabled_attr = __ATTR( - enabled, 0644, show_enabled, store_enabled -); +static struct kobj_attribute lru_gen_enabled_attr = __ATTR_RW(enabled); static struct attribute *lru_gen_attrs[] = { &lru_gen_min_ttl_attr.attr, @@ -5740,7 +5736,7 @@ static struct attribute *lru_gen_attrs[] = { NULL }; -static struct attribute_group lru_gen_attr_group = { +static const struct attribute_group lru_gen_attr_group = { .name = "lru_gen", .attrs = lru_gen_attrs, }; -- cgit v1.2.3 From aa464ba9a1e444d5ef95bb63ee3b2ef26fc96ed7 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 3 Feb 2023 17:18:34 +1000 Subject: lazy tlb: introduce lazy tlb mm refcount helper functions Add explicit _lazy_tlb annotated functions for lazy tlb mm refcounting. This makes the lazy tlb mm references more obvious, and allows the refcounting scheme to be modified in later changes. There is no functional change with this patch. Link: https://lkml.kernel.org/r/20230203071837.1136453-3-npiggin@gmail.com Signed-off-by: Nicholas Piggin Acked-by: Linus Torvalds Cc: Andy Lutomirski Cc: Catalin Marinas Cc: Christophe Leroy Cc: Dave Hansen Cc: Michael Ellerman Cc: Nadav Amit Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/arm/mach-rpc/ecard.c | 2 +- arch/powerpc/kernel/smp.c | 2 +- arch/powerpc/mm/book3s64/radix_tlb.c | 4 ++-- fs/exec.c | 2 +- include/linux/sched/mm.h | 16 ++++++++++++++++ kernel/cpu.c | 2 +- kernel/exit.c | 2 +- kernel/kthread.c | 12 ++++++++++-- kernel/sched/core.c | 15 ++++++++------- 9 files changed, 41 insertions(+), 16 deletions(-) (limited to 'include') diff --git a/arch/arm/mach-rpc/ecard.c b/arch/arm/mach-rpc/ecard.c index 53813f9464a2..c30df1097c52 100644 --- a/arch/arm/mach-rpc/ecard.c +++ b/arch/arm/mach-rpc/ecard.c @@ -253,7 +253,7 @@ static int ecard_init_mm(void) current->mm = mm; current->active_mm = mm; activate_mm(active_mm, mm); - mmdrop(active_mm); + mmdrop_lazy_tlb(active_mm); ecard_init_pgtables(mm); return 0; } diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 6b90f10a6c81..7db6b3faea65 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -1611,7 +1611,7 @@ void start_secondary(void *unused) if (IS_ENABLED(CONFIG_PPC32)) setup_kup(); - mmgrab(&init_mm); + mmgrab_lazy_tlb(&init_mm); current->active_mm = &init_mm; smp_store_cpu_info(cpu); diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c index e50bc5fc7ddf..ce804b7bf84e 100644 --- a/arch/powerpc/mm/book3s64/radix_tlb.c +++ b/arch/powerpc/mm/book3s64/radix_tlb.c @@ -797,10 +797,10 @@ void exit_lazy_flush_tlb(struct mm_struct *mm, bool always_flush) if (current->active_mm == mm) { WARN_ON_ONCE(current->mm != NULL); /* Is a kernel thread and is using mm as the lazy tlb */ - mmgrab(&init_mm); + mmgrab_lazy_tlb(&init_mm); current->active_mm = &init_mm; switch_mm_irqs_off(mm, &init_mm, current); - mmdrop(mm); + mmdrop_lazy_tlb(mm); } /* diff --git a/fs/exec.c b/fs/exec.c index 7c44d0c65b1b..87cf3a2f0e9a 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1034,7 +1034,7 @@ static int exec_mmap(struct mm_struct *mm) mmput(old_mm); return 0; } - mmdrop(active_mm); + mmdrop_lazy_tlb(active_mm); return 0; } diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 2a243616f222..5376caf6fcf3 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -79,6 +79,22 @@ static inline void mmdrop_sched(struct mm_struct *mm) } #endif +/* Helpers for lazy TLB mm refcounting */ +static inline void mmgrab_lazy_tlb(struct mm_struct *mm) +{ + mmgrab(mm); +} + +static inline void mmdrop_lazy_tlb(struct mm_struct *mm) +{ + mmdrop(mm); +} + +static inline void mmdrop_lazy_tlb_sched(struct mm_struct *mm) +{ + mmdrop_sched(mm); +} + /** * mmget() - Pin the address space associated with a &struct mm_struct. * @mm: The address space to pin. diff --git a/kernel/cpu.c b/kernel/cpu.c index 6c0a92ca6bb5..189895288d9d 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -623,7 +623,7 @@ static int finish_cpu(unsigned int cpu) */ if (mm != &init_mm) idle->active_mm = &init_mm; - mmdrop(mm); + mmdrop_lazy_tlb(mm); return 0; } diff --git a/kernel/exit.c b/kernel/exit.c index f2afdb0add7c..86902cb5ab78 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -537,7 +537,7 @@ static void exit_mm(void) return; sync_mm_rss(mm); mmap_read_lock(mm); - mmgrab(mm); + mmgrab_lazy_tlb(mm); BUG_ON(mm != current->active_mm); /* more a memory barrier than a real lock */ task_lock(current); diff --git a/kernel/kthread.c b/kernel/kthread.c index 1f1b60f1a746..470708c205e8 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -1415,6 +1415,11 @@ void kthread_use_mm(struct mm_struct *mm) WARN_ON_ONCE(!(tsk->flags & PF_KTHREAD)); WARN_ON_ONCE(tsk->mm); + /* + * It is possible for mm to be the same as tsk->active_mm, but + * we must still mmgrab(mm) and mmdrop_lazy_tlb(active_mm), + * because these references are not equivalent. + */ mmgrab(mm); task_lock(tsk); @@ -1438,9 +1443,9 @@ void kthread_use_mm(struct mm_struct *mm) * memory barrier after storing to tsk->mm, before accessing * user-space memory. A full memory barrier for membarrier * {PRIVATE,GLOBAL}_EXPEDITED is implicitly provided by - * mmdrop(). + * mmdrop_lazy_tlb(). */ - mmdrop(active_mm); + mmdrop_lazy_tlb(active_mm); } EXPORT_SYMBOL_GPL(kthread_use_mm); @@ -1468,10 +1473,13 @@ void kthread_unuse_mm(struct mm_struct *mm) local_irq_disable(); tsk->mm = NULL; membarrier_update_current_mm(NULL); + mmgrab_lazy_tlb(mm); /* active_mm is still 'mm' */ enter_lazy_tlb(mm, tsk); local_irq_enable(); task_unlock(tsk); + + mmdrop(mm); } EXPORT_SYMBOL_GPL(kthread_unuse_mm); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 0d18c3969f90..143e46bd2a68 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5203,13 +5203,14 @@ static struct rq *finish_task_switch(struct task_struct *prev) * rq->curr, before returning to userspace, so provide them here: * * - a full memory barrier for {PRIVATE,GLOBAL}_EXPEDITED, implicitly - * provided by mmdrop(), + * provided by mmdrop_lazy_tlb(), * - a sync_core for SYNC_CORE. */ if (mm) { membarrier_mm_sync_core_before_usermode(mm); - mmdrop_sched(mm); + mmdrop_lazy_tlb_sched(mm); } + if (unlikely(prev_state == TASK_DEAD)) { if (prev->sched_class->task_dead) prev->sched_class->task_dead(prev); @@ -5266,9 +5267,9 @@ context_switch(struct rq *rq, struct task_struct *prev, /* * kernel -> kernel lazy + transfer active - * user -> kernel lazy + mmgrab() active + * user -> kernel lazy + mmgrab_lazy_tlb() active * - * kernel -> user switch + mmdrop() active + * kernel -> user switch + mmdrop_lazy_tlb() active * user -> user switch */ if (!next->mm) { // to kernel @@ -5276,7 +5277,7 @@ context_switch(struct rq *rq, struct task_struct *prev, next->active_mm = prev->active_mm; if (prev->mm) // from user - mmgrab(prev->active_mm); + mmgrab_lazy_tlb(prev->active_mm); else prev->active_mm = NULL; } else { // to user @@ -5293,7 +5294,7 @@ context_switch(struct rq *rq, struct task_struct *prev, lru_gen_use_mm(next->mm); if (!prev->mm) { // from kernel - /* will mmdrop() in finish_task_switch(). */ + /* will mmdrop_lazy_tlb() in finish_task_switch(). */ rq->prev_mm = prev->active_mm; prev->active_mm = NULL; } @@ -9935,7 +9936,7 @@ void __init sched_init(void) /* * The boot idle thread does lazy MMU switching as well: */ - mmgrab(&init_mm); + mmgrab_lazy_tlb(&init_mm); enter_lazy_tlb(&init_mm, current); /* -- cgit v1.2.3 From 88e3009b5283bbd41447f0352d0b9df16cf6f183 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 3 Feb 2023 17:18:35 +1000 Subject: lazy tlb: allow lazy tlb mm refcounting to be configurable Add CONFIG_MMU_TLB_REFCOUNT which enables refcounting of the lazy tlb mm when it is context switched. This can be disabled by architectures that don't require this refcounting if they clean up lazy tlb mms when the last refcount is dropped. Currently this is always enabled, so the patch introduces no functional change. Link: https://lkml.kernel.org/r/20230203071837.1136453-4-npiggin@gmail.com Signed-off-by: Nicholas Piggin Acked-by: Linus Torvalds Cc: Andy Lutomirski Cc: Catalin Marinas Cc: Christophe Leroy Cc: Dave Hansen Cc: Michael Ellerman Cc: Nadav Amit Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Signed-off-by: Andrew Morton --- Documentation/mm/active_mm.rst | 6 ++++++ arch/Kconfig | 17 +++++++++++++++++ include/linux/sched/mm.h | 18 +++++++++++++++--- 3 files changed, 38 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/Documentation/mm/active_mm.rst b/Documentation/mm/active_mm.rst index 45d89f8fb3a8..d096fc091e23 100644 --- a/Documentation/mm/active_mm.rst +++ b/Documentation/mm/active_mm.rst @@ -2,6 +2,12 @@ Active MM ========= +Note, the mm_count refcount may no longer include the "lazy" users +(running tasks with ->active_mm == mm && ->mm == NULL) on kernels +with CONFIG_MMU_LAZY_TLB_REFCOUNT=n. Taking and releasing these lazy +references must be done with mmgrab_lazy_tlb() and mmdrop_lazy_tlb() +helpers, which abstract this config option. + :: List: linux-kernel diff --git a/arch/Kconfig b/arch/Kconfig index e3511afbb7f2..643f8a04141e 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -465,6 +465,23 @@ config ARCH_WANT_IRQS_OFF_ACTIVATE_MM irqs disabled over activate_mm. Architectures that do IPI based TLB shootdowns should enable this. +# Use normal mm refcounting for MMU_LAZY_TLB kernel thread references. +# MMU_LAZY_TLB_REFCOUNT=n can improve the scalability of context switching +# to/from kernel threads when the same mm is running on a lot of CPUs (a large +# multi-threaded application), by reducing contention on the mm refcount. +# +# This can be disabled if the architecture ensures no CPUs are using an mm as a +# "lazy tlb" beyond its final refcount (i.e., by the time __mmdrop frees the mm +# or its kernel page tables). This could be arranged by arch_exit_mmap(), or +# final exit(2) TLB flush, for example. +# +# To implement this, an arch *must*: +# Ensure the _lazy_tlb variants of mmgrab/mmdrop are used when manipulating +# the lazy tlb reference of a kthread's ->active_mm (non-arch code has been +# converted already). +config MMU_LAZY_TLB_REFCOUNT + def_bool y + config ARCH_HAVE_NMI_SAFE_CMPXCHG bool diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 5376caf6fcf3..689dbe812563 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -82,17 +82,29 @@ static inline void mmdrop_sched(struct mm_struct *mm) /* Helpers for lazy TLB mm refcounting */ static inline void mmgrab_lazy_tlb(struct mm_struct *mm) { - mmgrab(mm); + if (IS_ENABLED(CONFIG_MMU_LAZY_TLB_REFCOUNT)) + mmgrab(mm); } static inline void mmdrop_lazy_tlb(struct mm_struct *mm) { - mmdrop(mm); + if (IS_ENABLED(CONFIG_MMU_LAZY_TLB_REFCOUNT)) { + mmdrop(mm); + } else { + /* + * mmdrop_lazy_tlb must provide a full memory barrier, see the + * membarrier comment finish_task_switch which relies on this. + */ + smp_mb(); + } } static inline void mmdrop_lazy_tlb_sched(struct mm_struct *mm) { - mmdrop_sched(mm); + if (IS_ENABLED(CONFIG_MMU_LAZY_TLB_REFCOUNT)) + mmdrop_sched(mm); + else + smp_mb(); /* see mmdrop_lazy_tlb() above */ } /** -- cgit v1.2.3 From 739100c88f49a67c6487bb2d826b0b5a2ddc80e2 Mon Sep 17 00:00:00 2001 From: Stefan Roesch Date: Fri, 10 Feb 2023 13:46:45 -0800 Subject: mm: add tracepoints to ksm This adds the following tracepoints to ksm: - start / stop scan - ksm enter / exit - merge a page - merge a page with ksm - remove a page - remove a rmap item This patch has been split off from the RFC patch series "mm: process/cgroup ksm support". Link: https://lkml.kernel.org/r/20230210214645.2720847-1-shr@devkernel.io Signed-off-by: Stefan Roesch Reviewed-by: Steven Rostedt (Google) Signed-off-by: Andrew Morton --- MAINTAINERS | 1 + include/trace/events/ksm.h | 251 +++++++++++++++++++++++++++++++++++++++++++++ mm/ksm.c | 21 +++- 3 files changed, 271 insertions(+), 2 deletions(-) create mode 100644 include/trace/events/ksm.h (limited to 'include') diff --git a/MAINTAINERS b/MAINTAINERS index 1dc8bd26b6cf..a62ffb710b47 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13409,6 +13409,7 @@ F: include/linux/memory_hotplug.h F: include/linux/mm.h F: include/linux/mmzone.h F: include/linux/pagewalk.h +F: include/trace/events/ksm.h F: mm/ F: tools/mm/ F: tools/testing/selftests/mm/ diff --git a/include/trace/events/ksm.h b/include/trace/events/ksm.h new file mode 100644 index 000000000000..b5ac35c1d0e8 --- /dev/null +++ b/include/trace/events/ksm.h @@ -0,0 +1,251 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM ksm + +#if !defined(_TRACE_KSM_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_KSM_H + +#include + +/** + * ksm_scan_template - called for start / stop scan + * + * @seq: sequence number of scan + * @rmap_entries: actual number of rmap entries + * + * Allows to trace the start / stop of a ksm scan. + */ +DECLARE_EVENT_CLASS(ksm_scan_template, + + TP_PROTO(int seq, u32 rmap_entries), + + TP_ARGS(seq, rmap_entries), + + TP_STRUCT__entry( + __field(int, seq) + __field(u32, rmap_entries) + ), + + TP_fast_assign( + __entry->seq = seq; + __entry->rmap_entries = rmap_entries; + ), + + TP_printk("seq %d rmap size %d", + __entry->seq, __entry->rmap_entries) +); + +/** + * ksm_start_scan - called after a new ksm scan is started + * + * @seq: sequence number of scan + * @rmap_entries: actual number of rmap entries + * + * Allows to trace the start of a ksm scan. + */ +DEFINE_EVENT(ksm_scan_template, ksm_start_scan, + + TP_PROTO(int seq, u32 rmap_entries), + + TP_ARGS(seq, rmap_entries) +); + +/** + * ksm_stop_scan - called after a new ksm scan has completed + * + * @seq: sequence number of scan + * @rmap_entries: actual number of rmap entries + * + * Allows to trace the completion of a ksm scan. + */ +DEFINE_EVENT(ksm_scan_template, ksm_stop_scan, + + TP_PROTO(int seq, u32 rmap_entries), + + TP_ARGS(seq, rmap_entries) +); + +/** + * ksm_enter - called after a new process has been added / removed from ksm + * + * @mm: address of the mm object of the process + * + * Allows to trace the when a process has been added or removed from ksm. + */ +DECLARE_EVENT_CLASS(ksm_enter_exit_template, + + TP_PROTO(void *mm), + + TP_ARGS(mm), + + TP_STRUCT__entry( + __field(void *, mm) + ), + + TP_fast_assign( + __entry->mm = mm; + ), + + TP_printk("mm %p", __entry->mm) +); + +/** + * ksm_enter - called after a new process has been added to ksm + * + * @mm: address of the mm object of the process + * + * Allows to trace the when a process has been added to ksm. + */ +DEFINE_EVENT(ksm_enter_exit_template, ksm_enter, + + TP_PROTO(void *mm), + + TP_ARGS(mm) +); + +/** + * ksm_exit - called after a new process has been removed from ksm + * + * @mm: address of the mm object of the process + * + * Allows to trace the when a process has been removed from ksm. + */ +DEFINE_EVENT(ksm_enter_exit_template, ksm_exit, + + TP_PROTO(void *mm), + + TP_ARGS(mm) +); + +/** + * ksm_merge_one_page - called after a page has been merged + * + * @pfn: page frame number of ksm page + * @rmap_item: address of rmap_item object + * @mm: address of the process mm struct + * @err: success + * + * Allows to trace the ksm merging of individual pages. + */ +TRACE_EVENT(ksm_merge_one_page, + + TP_PROTO(unsigned long pfn, void *rmap_item, void *mm, int err), + + TP_ARGS(pfn, rmap_item, mm, err), + + TP_STRUCT__entry( + __field(unsigned long, pfn) + __field(void *, rmap_item) + __field(void *, mm) + __field(int, err) + ), + + TP_fast_assign( + __entry->pfn = pfn; + __entry->rmap_item = rmap_item; + __entry->mm = mm; + __entry->err = err; + ), + + TP_printk("ksm pfn %lu rmap_item %p mm %p error %d", + __entry->pfn, __entry->rmap_item, __entry->mm, __entry->err) +); + +/** + * ksm_merge_with_ksm_page - called after a page has been merged with a ksm page + * + * @ksm_page: address ksm page + * @pfn: page frame number of ksm page + * @rmap_item: address of rmap_item object + * @mm: address of the mm object of the process + * @err: success + * + * Allows to trace the merging of a page with a ksm page. + */ +TRACE_EVENT(ksm_merge_with_ksm_page, + + TP_PROTO(void *ksm_page, unsigned long pfn, void *rmap_item, void *mm, int err), + + TP_ARGS(ksm_page, pfn, rmap_item, mm, err), + + TP_STRUCT__entry( + __field(void *, ksm_page) + __field(unsigned long, pfn) + __field(void *, rmap_item) + __field(void *, mm) + __field(int, err) + ), + + TP_fast_assign( + __entry->ksm_page = ksm_page; + __entry->pfn = pfn; + __entry->rmap_item = rmap_item; + __entry->mm = mm; + __entry->err = err; + ), + + TP_printk("%spfn %lu rmap_item %p mm %p error %d", + (__entry->ksm_page ? "ksm " : ""), + __entry->pfn, __entry->rmap_item, __entry->mm, __entry->err) +); + +/** + * ksm_remove_ksm_page - called after a ksm page has been removed + * + * @pfn: page frame number of ksm page + * + * Allows to trace the removing of stable ksm pages. + */ +TRACE_EVENT(ksm_remove_ksm_page, + + TP_PROTO(unsigned long pfn), + + TP_ARGS(pfn), + + TP_STRUCT__entry( + __field(unsigned long, pfn) + ), + + TP_fast_assign( + __entry->pfn = pfn; + ), + + TP_printk("pfn %lu", __entry->pfn) +); + +/** + * ksm_remove_rmap_item - called after a rmap_item has been removed from the + * stable tree + * + * @pfn: page frame number of ksm page + * @rmap_item: address of rmap_item object + * @mm: address of the process mm struct + * + * Allows to trace the removal of pages from the stable tree list. + */ +TRACE_EVENT(ksm_remove_rmap_item, + + TP_PROTO(unsigned long pfn, void *rmap_item, void *mm), + + TP_ARGS(pfn, rmap_item, mm), + + TP_STRUCT__entry( + __field(unsigned long, pfn) + __field(void *, rmap_item) + __field(void *, mm) + ), + + TP_fast_assign( + __entry->pfn = pfn; + __entry->rmap_item = rmap_item; + __entry->mm = mm; + ), + + TP_printk("pfn %lu rmap_item %p mm %p", + __entry->pfn, __entry->rmap_item, __entry->mm) +); + +#endif /* _TRACE_KSM_H */ + +/* This part must be outside protection */ +#include diff --git a/mm/ksm.c b/mm/ksm.c index 2b8d30068cbb..290a3eb6d8de 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -45,6 +45,9 @@ #include "internal.h" #include "mm_slot.h" +#define CREATE_TRACE_POINTS +#include + #ifdef CONFIG_NUMA #define NUMA(x) (x) #define DO_NUMA(x) do { (x); } while (0) @@ -633,10 +636,12 @@ static void remove_node_from_stable_tree(struct ksm_stable_node *stable_node) BUG_ON(stable_node->rmap_hlist_len < 0); hlist_for_each_entry(rmap_item, &stable_node->hlist, hlist) { - if (rmap_item->hlist.next) + if (rmap_item->hlist.next) { ksm_pages_sharing--; - else + trace_ksm_remove_rmap_item(stable_node->kpfn, rmap_item, rmap_item->mm); + } else { ksm_pages_shared--; + } rmap_item->mm->ksm_merging_pages--; @@ -657,6 +662,7 @@ static void remove_node_from_stable_tree(struct ksm_stable_node *stable_node) BUILD_BUG_ON(STABLE_NODE_DUP_HEAD <= &migrate_nodes); BUILD_BUG_ON(STABLE_NODE_DUP_HEAD >= &migrate_nodes + 1); + trace_ksm_remove_ksm_page(stable_node->kpfn); if (stable_node->head == &migrate_nodes) list_del(&stable_node->list); else @@ -1324,6 +1330,8 @@ static int try_to_merge_with_ksm_page(struct ksm_rmap_item *rmap_item, get_anon_vma(vma->anon_vma); out: mmap_read_unlock(mm); + trace_ksm_merge_with_ksm_page(kpage, page_to_pfn(kpage ? kpage : page), + rmap_item, mm, err); return err; } @@ -2142,6 +2150,9 @@ static void cmp_and_merge_page(struct page *page, struct ksm_rmap_item *rmap_ite if (vma) { err = try_to_merge_one_page(vma, page, ZERO_PAGE(rmap_item->address)); + trace_ksm_merge_one_page( + page_to_pfn(ZERO_PAGE(rmap_item->address)), + rmap_item, mm, err); } else { /* * If the vma is out of date, we do not need to @@ -2264,6 +2275,8 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page) mm_slot = ksm_scan.mm_slot; if (mm_slot == &ksm_mm_head) { + trace_ksm_start_scan(ksm_scan.seqnr, ksm_rmap_items); + /* * A number of pages can hang around indefinitely on per-cpu * pagevecs, raised page count preventing write_protect_page @@ -2414,6 +2427,7 @@ no_vmas: if (mm_slot != &ksm_mm_head) goto next_mm; + trace_ksm_stop_scan(ksm_scan.seqnr, ksm_rmap_items); ksm_scan.seqnr++; return NULL; } @@ -2565,6 +2579,7 @@ int __ksm_enter(struct mm_struct *mm) if (needs_wakeup) wake_up_interruptible(&ksm_thread_wait); + trace_ksm_enter(mm); return 0; } @@ -2606,6 +2621,8 @@ void __ksm_exit(struct mm_struct *mm) mmap_write_lock(mm); mmap_write_unlock(mm); } + + trace_ksm_exit(mm); } struct page *ksm_might_need_to_copy(struct page *page, -- cgit v1.2.3 From e26fcc02c7f6c76cba42d043756e35a78ce9ac11 Mon Sep 17 00:00:00 2001 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> Date: Mon, 30 Jan 2023 13:25:12 +0900 Subject: mmflags.h: use less error prone method to define pageflag_names Patch series "mm, printk: introduce new format for page_type", v4. This series moves PG_slab page flag to page_type, freeing one bit in page->flags and introduces %pGt format that prints human-readable page_type like %pGp for printing page flags. See changelog of patch 2 for more implementation details. Thanks everyone that gave valuable comments. This patch (of 3): Use helper macro to decrease chances of typo when defining pageflag_names. Link: https://lkml.kernel.org/r/20230130042514.2418-1-42.hyeyoo@gmail.com Link: https://lore.kernel.org/lkml/Y6AycLbpjVzXM5I9@smile.fi.intel.com Link: https://lkml.kernel.org/r/20230130042514.2418-2-42.hyeyoo@gmail.com Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Suggested-by: Andy Shevchenko Reviewed-by: Andy Shevchenko Cc: David Hildenbrand Cc: Joe Perches Cc: Matthew Wilcox Cc: Petr Mladek Cc: Steven Rostedt (Google) Cc: Vlastimil Babka Cc: Sergey Senozhatsky Cc: Steven Rostedt Cc: John Ogness Signed-off-by: Andrew Morton --- include/trace/events/mmflags.h | 85 ++++++++++++++++++++++-------------------- 1 file changed, 44 insertions(+), 41 deletions(-) (limited to 'include') diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h index 9db52bc4ce19..f453babe29b3 100644 --- a/include/trace/events/mmflags.h +++ b/include/trace/events/mmflags.h @@ -67,71 +67,74 @@ ) : "none" #ifdef CONFIG_MMU -#define IF_HAVE_PG_MLOCK(flag,string) ,{1UL << flag, string} +#define IF_HAVE_PG_MLOCK(_name) ,{1UL << PG_##_name, __stringify(_name)} #else -#define IF_HAVE_PG_MLOCK(flag,string) +#define IF_HAVE_PG_MLOCK(_name) #endif #ifdef CONFIG_ARCH_USES_PG_UNCACHED -#define IF_HAVE_PG_UNCACHED(flag,string) ,{1UL << flag, string} +#define IF_HAVE_PG_UNCACHED(_name) ,{1UL << PG_##_name, __stringify(_name)} #else -#define IF_HAVE_PG_UNCACHED(flag,string) +#define IF_HAVE_PG_UNCACHED(_name) #endif #ifdef CONFIG_MEMORY_FAILURE -#define IF_HAVE_PG_HWPOISON(flag,string) ,{1UL << flag, string} +#define IF_HAVE_PG_HWPOISON(_name) ,{1UL << PG_##_name, __stringify(_name)} #else -#define IF_HAVE_PG_HWPOISON(flag,string) +#define IF_HAVE_PG_HWPOISON(_name) #endif #if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT) -#define IF_HAVE_PG_IDLE(flag,string) ,{1UL << flag, string} +#define IF_HAVE_PG_IDLE(_name) ,{1UL << PG_##_name, __stringify(_name)} #else -#define IF_HAVE_PG_IDLE(flag,string) +#define IF_HAVE_PG_IDLE(_name) #endif #ifdef CONFIG_ARCH_USES_PG_ARCH_X -#define IF_HAVE_PG_ARCH_X(flag,string) ,{1UL << flag, string} +#define IF_HAVE_PG_ARCH_X(_name) ,{1UL << PG_##_name, __stringify(_name)} #else -#define IF_HAVE_PG_ARCH_X(flag,string) +#define IF_HAVE_PG_ARCH_X(_name) #endif #ifdef CONFIG_KASAN_HW_TAGS -#define IF_HAVE_PG_SKIP_KASAN_POISON(flag,string) ,{1UL << flag, string} +#define IF_HAVE_PG_SKIP_KASAN_POISON(_name) \ + ,{1UL << PG_##_name, __stringify(_name)} #else -#define IF_HAVE_PG_SKIP_KASAN_POISON(flag,string) +#define IF_HAVE_PG_SKIP_KASAN_POISON(_name) #endif +#define DEF_PAGEFLAG_NAME(_name) { 1UL << PG_##_name, __stringify(_name) } + #define __def_pageflag_names \ - {1UL << PG_locked, "locked" }, \ - {1UL << PG_waiters, "waiters" }, \ - {1UL << PG_error, "error" }, \ - {1UL << PG_referenced, "referenced" }, \ - {1UL << PG_uptodate, "uptodate" }, \ - {1UL << PG_dirty, "dirty" }, \ - {1UL << PG_lru, "lru" }, \ - {1UL << PG_active, "active" }, \ - {1UL << PG_workingset, "workingset" }, \ - {1UL << PG_slab, "slab" }, \ - {1UL << PG_owner_priv_1, "owner_priv_1" }, \ - {1UL << PG_arch_1, "arch_1" }, \ - {1UL << PG_reserved, "reserved" }, \ - {1UL << PG_private, "private" }, \ - {1UL << PG_private_2, "private_2" }, \ - {1UL << PG_writeback, "writeback" }, \ - {1UL << PG_head, "head" }, \ - {1UL << PG_mappedtodisk, "mappedtodisk" }, \ - {1UL << PG_reclaim, "reclaim" }, \ - {1UL << PG_swapbacked, "swapbacked" }, \ - {1UL << PG_unevictable, "unevictable" } \ -IF_HAVE_PG_MLOCK(PG_mlocked, "mlocked" ) \ -IF_HAVE_PG_UNCACHED(PG_uncached, "uncached" ) \ -IF_HAVE_PG_HWPOISON(PG_hwpoison, "hwpoison" ) \ -IF_HAVE_PG_IDLE(PG_young, "young" ) \ -IF_HAVE_PG_IDLE(PG_idle, "idle" ) \ -IF_HAVE_PG_ARCH_X(PG_arch_2, "arch_2" ) \ -IF_HAVE_PG_ARCH_X(PG_arch_3, "arch_3" ) \ -IF_HAVE_PG_SKIP_KASAN_POISON(PG_skip_kasan_poison, "skip_kasan_poison") + DEF_PAGEFLAG_NAME(locked), \ + DEF_PAGEFLAG_NAME(waiters), \ + DEF_PAGEFLAG_NAME(error), \ + DEF_PAGEFLAG_NAME(referenced), \ + DEF_PAGEFLAG_NAME(uptodate), \ + DEF_PAGEFLAG_NAME(dirty), \ + DEF_PAGEFLAG_NAME(lru), \ + DEF_PAGEFLAG_NAME(active), \ + DEF_PAGEFLAG_NAME(workingset), \ + DEF_PAGEFLAG_NAME(slab), \ + DEF_PAGEFLAG_NAME(owner_priv_1), \ + DEF_PAGEFLAG_NAME(arch_1), \ + DEF_PAGEFLAG_NAME(reserved), \ + DEF_PAGEFLAG_NAME(private), \ + DEF_PAGEFLAG_NAME(private_2), \ + DEF_PAGEFLAG_NAME(writeback), \ + DEF_PAGEFLAG_NAME(head), \ + DEF_PAGEFLAG_NAME(mappedtodisk), \ + DEF_PAGEFLAG_NAME(reclaim), \ + DEF_PAGEFLAG_NAME(swapbacked), \ + DEF_PAGEFLAG_NAME(unevictable) \ +IF_HAVE_PG_MLOCK(mlocked) \ +IF_HAVE_PG_UNCACHED(uncached) \ +IF_HAVE_PG_HWPOISON(hwpoison) \ +IF_HAVE_PG_IDLE(idle) \ +IF_HAVE_PG_IDLE(young) \ +IF_HAVE_PG_ARCH_X(arch_2) \ +IF_HAVE_PG_ARCH_X(arch_3) \ +IF_HAVE_PG_SKIP_KASAN_POISON(skip_kasan_poison) #define show_page_flags(flags) \ (flags) ? __print_flags(flags, "|", \ -- cgit v1.2.3 From 4c85c0be3d7a9a7ffe48bfe0954eacc0ba9d3c75 Mon Sep 17 00:00:00 2001 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> Date: Mon, 30 Jan 2023 13:25:13 +0900 Subject: mm, printk: introduce new format %pGt for page_type %pGp format is used to display 'flags' field of a struct page. However, some page flags (i.e. PG_buddy, see page-flags.h for more details) are stored in page_type field. To display human-readable output of page_type, introduce %pGt format. It is important to note the meaning of bits are different in page_type. if page_type is 0xffffffff, no flags are set. Setting PG_buddy (0x00000080) flag results in a page_type of 0xffffff7f. Clearing a bit actually means setting a flag. Bits in page_type are inverted when displaying type names. Only values for which page_type_has_type() returns true are considered as page_type, to avoid confusion with mapcount values. if it returns false, only raw values are displayed and not page type names. Link: https://lkml.kernel.org/r/20230130042514.2418-3-42.hyeyoo@gmail.com Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Petr Mladek [vsprintf part] Cc: Andy Shevchenko Cc: David Hildenbrand Cc: Joe Perches Cc: John Ogness Cc: Matthew Wilcox Cc: Sergey Senozhatsky Cc: Steven Rostedt (Google) Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- Documentation/core-api/printk-formats.rst | 16 +++++++++++----- include/linux/page-flags.h | 7 ++++++- include/trace/events/mmflags.h | 8 ++++++++ lib/test_printf.c | 26 ++++++++++++++++++++++++++ lib/vsprintf.c | 21 +++++++++++++++++++++ mm/debug.c | 5 +++++ mm/internal.h | 1 + 7 files changed, 78 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst index dbe1aacc79d0..dfe7e75a71de 100644 --- a/Documentation/core-api/printk-formats.rst +++ b/Documentation/core-api/printk-formats.rst @@ -575,20 +575,26 @@ The field width is passed by value, the bitmap is passed by reference. Helper macros cpumask_pr_args() and nodemask_pr_args() are available to ease printing cpumask and nodemask. -Flags bitfields such as page flags, gfp_flags ---------------------------------------------- +Flags bitfields such as page flags, page_type, gfp_flags +-------------------------------------------------------- :: %pGp 0x17ffffc0002036(referenced|uptodate|lru|active|private|node=0|zone=2|lastcpupid=0x1fffff) + %pGt 0xffffff7f(buddy) %pGg GFP_USER|GFP_DMA32|GFP_NOWARN %pGv read|exec|mayread|maywrite|mayexec|denywrite For printing flags bitfields as a collection of symbolic constants that would construct the value. The type of flags is given by the third -character. Currently supported are [p]age flags, [v]ma_flags (both -expect ``unsigned long *``) and [g]fp_flags (expects ``gfp_t *``). The flag -names and print order depends on the particular type. +character. Currently supported are: + + - p - [p]age flags, expects value of type (``unsigned long *``) + - t - page [t]ype, expects value of type (``unsigned int *``) + - v - [v]ma_flags, expects value of type (``unsigned long *``) + - g - [g]fp_flags, expects value of type (``gfp_t *``) + +The flag names and print order depends on the particular type. Note that this format should not be used directly in the :c:func:`TP_printk()` part of a tracepoint. Instead, use the show_*_flags() diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index a7e3a3405520..57287102c5bd 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -926,9 +926,14 @@ static inline bool is_page_hwpoison(struct page *page) #define PageType(page, flag) \ ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) +static inline int page_type_has_type(unsigned int page_type) +{ + return (int)page_type < PAGE_MAPCOUNT_RESERVE; +} + static inline int page_has_type(struct page *page) { - return (int)page->page_type < PAGE_MAPCOUNT_RESERVE; + return page_type_has_type(page->page_type); } #define PAGE_TYPE_OPS(uname, lname) \ diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h index f453babe29b3..b28218b7998e 100644 --- a/include/trace/events/mmflags.h +++ b/include/trace/events/mmflags.h @@ -141,6 +141,14 @@ IF_HAVE_PG_SKIP_KASAN_POISON(skip_kasan_poison) __def_pageflag_names \ ) : "none" +#define DEF_PAGETYPE_NAME(_name) { PG_##_name, __stringify(_name) } + +#define __def_pagetype_names \ + DEF_PAGETYPE_NAME(offline), \ + DEF_PAGETYPE_NAME(guard), \ + DEF_PAGETYPE_NAME(table), \ + DEF_PAGETYPE_NAME(buddy) + #if defined(CONFIG_X86) #define __VM_ARCH_SPECIFIC_1 {VM_PAT, "pat" } #elif defined(CONFIG_PPC) diff --git a/lib/test_printf.c b/lib/test_printf.c index 46b4e6c414a3..7677ebccf3c3 100644 --- a/lib/test_printf.c +++ b/lib/test_printf.c @@ -642,12 +642,26 @@ page_flags_test(int section, int node, int zone, int last_cpupid, test(cmp_buf, "%pGp", &flags); } +static void __init page_type_test(unsigned int page_type, const char *name, + char *cmp_buf) +{ + unsigned long size; + + size = scnprintf(cmp_buf, BUF_SIZE, "%#x(", page_type); + if (page_type_has_type(page_type)) + size += scnprintf(cmp_buf + size, BUF_SIZE - size, "%s", name); + + snprintf(cmp_buf + size, BUF_SIZE - size, ")"); + test(cmp_buf, "%pGt", &page_type); +} + static void __init flags(void) { unsigned long flags; char *cmp_buffer; gfp_t gfp; + unsigned int page_type; cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL); if (!cmp_buffer) @@ -687,6 +701,18 @@ flags(void) gfp |= __GFP_HIGH; test(cmp_buffer, "%pGg", &gfp); + page_type = ~0; + page_type_test(page_type, "", cmp_buffer); + + page_type = 10; + page_type_test(page_type, "", cmp_buffer); + + page_type = ~PG_buddy; + page_type_test(page_type, "buddy", cmp_buffer); + + page_type = ~(PG_table | PG_buddy); + page_type_test(page_type, "table|buddy", cmp_buffer); + kfree(cmp_buffer); } diff --git a/lib/vsprintf.c b/lib/vsprintf.c index be71a03c936a..fbe320b5e89f 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -2052,6 +2052,25 @@ char *format_page_flags(char *buf, char *end, unsigned long flags) return buf; } +static +char *format_page_type(char *buf, char *end, unsigned int page_type) +{ + buf = number(buf, end, page_type, default_flag_spec); + + if (buf < end) + *buf = '('; + buf++; + + if (page_type_has_type(page_type)) + buf = format_flags(buf, end, ~page_type, pagetype_names); + + if (buf < end) + *buf = ')'; + buf++; + + return buf; +} + static noinline_for_stack char *flags_string(char *buf, char *end, void *flags_ptr, struct printf_spec spec, const char *fmt) @@ -2065,6 +2084,8 @@ char *flags_string(char *buf, char *end, void *flags_ptr, switch (fmt[1]) { case 'p': return format_page_flags(buf, end, *(unsigned long *)flags_ptr); + case 't': + return format_page_type(buf, end, *(unsigned int *)flags_ptr); case 'v': flags = *(unsigned long *)flags_ptr; names = vmaflag_names; diff --git a/mm/debug.c b/mm/debug.c index 96d594e16292..01cf0435723b 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -36,6 +36,11 @@ const struct trace_print_flags pageflag_names[] = { {0, NULL} }; +const struct trace_print_flags pagetype_names[] = { + __def_pagetype_names, + {0, NULL} +}; + const struct trace_print_flags gfpflag_names[] = { __def_gfpflag_names, {0, NULL} diff --git a/mm/internal.h b/mm/internal.h index 7920a8b7982e..2a7ffd9962c4 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -802,6 +802,7 @@ static inline void flush_tlb_batched_pending(struct mm_struct *mm) #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ extern const struct trace_print_flags pageflag_names[]; +extern const struct trace_print_flags pagetype_names[]; extern const struct trace_print_flags vmaflag_names[]; extern const struct trace_print_flags gfpflag_names[]; -- cgit v1.2.3 From 16d91faf09be148d9c1cf4999f4d15fb24a7cd72 Mon Sep 17 00:00:00 2001 From: Peter Collingbourne Date: Thu, 16 Feb 2023 11:59:24 -0800 Subject: kasan: call clear_page with a match-all tag instead of changing page tag Instead of changing the page's tag solely in order to obtain a pointer with a match-all tag and then changing it back again, just convert the pointer that we get from kmap_atomic() into one with a match-all tag before passing it to clear_page(). On a certain microarchitecture, this has been observed to cause a measurable improvement in microbenchmark performance, presumably as a result of being able to avoid the atomic operations on the page tag. Link: https://lkml.kernel.org/r/20230216195924.3287772-1-pcc@google.com Signed-off-by: Peter Collingbourne Link: https://linux-review.googlesource.com/id/I0249822cc29097ca7a04ad48e8eb14871f80e711 Reviewed-by: Andrey Konovalov Reviewed-by: Catalin Marinas Cc: Andrey Ryabinin Cc: Evgenii Stepanov Cc: Peter Collingbourne Cc: Vincenzo Frascino Cc: Will Deacon Signed-off-by: Andrew Morton --- include/linux/highmem.h | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 8fc10089e19e..9c7cdaa3de8c 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -243,12 +243,10 @@ static inline void clear_highpage(struct page *page) static inline void clear_highpage_kasan_tagged(struct page *page) { - u8 tag; + void *kaddr = kmap_local_page(page); - tag = page_kasan_tag(page); - page_kasan_tag_reset(page); - clear_highpage(page); - page_kasan_tag_set(page, tag); + clear_page(kasan_reset_tag(kaddr)); + kunmap_local(kaddr); } #ifndef __HAVE_ARCH_TAG_CLEAR_HIGHPAGE -- cgit v1.2.3 From 3e4fb13ac34bad94cf390415b1e6bc3ca9520d65 Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Thu, 2 Mar 2023 19:58:35 +0800 Subject: mm: swap: remove unneeded cgroup_throttle_swaprate() All the callers of cgroup_throttle_swaprate() are converted to folio_throttle_swaprate(), so make __cgroup_throttle_swaprate() to take a folio, and rename it to __folio_throttle_swaprate(), also rename gfp_mask to gfp and drop redundant extern keyword. finally, drop unused cgroup_throttle_swaprate(). Link: https://lkml.kernel.org/r/20230302115835.105364-8-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Reviewed-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- include/linux/swap.h | 12 ++++-------- mm/swapfile.c | 6 +++--- 2 files changed, 7 insertions(+), 11 deletions(-) (limited to 'include') diff --git a/include/linux/swap.h b/include/linux/swap.h index 209a425739a9..d5d0b54e90e8 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -641,22 +641,18 @@ extern atomic_t zswap_stored_pages; #endif #if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) -extern void __cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask); -static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask) +void __folio_throttle_swaprate(struct folio *folio, gfp_t gfp); +static inline void folio_throttle_swaprate(struct folio *folio, gfp_t gfp) { if (mem_cgroup_disabled()) return; - __cgroup_throttle_swaprate(page, gfp_mask); + __folio_throttle_swaprate(folio, gfp); } #else -static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask) -{ -} -#endif static inline void folio_throttle_swaprate(struct folio *folio, gfp_t gfp) { - cgroup_throttle_swaprate(&folio->page, gfp); } +#endif #if defined(CONFIG_MEMCG) && defined(CONFIG_SWAP) void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry); diff --git a/mm/swapfile.c b/mm/swapfile.c index 62ba2bf577d7..c1b97436f811 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3635,12 +3635,12 @@ static void free_swap_count_continuations(struct swap_info_struct *si) } #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) -void __cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask) +void __folio_throttle_swaprate(struct folio *folio, gfp_t gfp) { struct swap_info_struct *si, *next; - int nid = page_to_nid(page); + int nid = folio_nid(folio); - if (!(gfp_mask & __GFP_IO)) + if (!(gfp & __GFP_IO)) return; if (!blk_cgroup_congested()) -- cgit v1.2.3 From 99c29133639a29fa803ea27ec79bf9e732efd062 Mon Sep 17 00:00:00 2001 From: Gerald Schaefer Date: Mon, 6 Mar 2023 17:15:48 +0100 Subject: mm: add PTE pointer parameter to flush_tlb_fix_spurious_fault() s390 can do more fine-grained handling of spurious TLB protection faults, when there also is the PTE pointer available. Therefore, pass on the PTE pointer to flush_tlb_fix_spurious_fault() as an additional parameter. This will add no functional change to other architectures, but those with private flush_tlb_fix_spurious_fault() implementations need to be made aware of the new parameter. Link: https://lkml.kernel.org/r/20230306161548.661740-1-gerald.schaefer@linux.ibm.com Signed-off-by: Gerald Schaefer Reviewed-by: Alexander Gordeev Acked-by: Catalin Marinas [arm64] Acked-by: Michael Ellerman [powerpc] Acked-by: David Hildenbrand Cc: Anshuman Khandual Cc: Borislav Petkov (AMD) Cc: Christophe Leroy Cc: Dave Hansen Cc: Ingo Molnar Cc: Matthew Wilcox (Oracle) Cc: Nicholas Piggin Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/arm64/include/asm/pgtable.h | 2 +- arch/mips/include/asm/pgtable.h | 3 ++- arch/powerpc/include/asm/book3s/64/tlbflush.h | 3 ++- arch/s390/include/asm/pgtable.h | 12 +++++++----- arch/x86/include/asm/pgtable.h | 2 +- include/linux/pgtable.h | 2 +- mm/memory.c | 3 ++- mm/pgtable-generic.c | 2 +- 8 files changed, 17 insertions(+), 12 deletions(-) (limited to 'include') diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index b6ba466e2e8a..0bd18de9fd97 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -57,7 +57,7 @@ static inline bool arch_thp_swp_supported(void) * fault on one CPU which has been handled concurrently by another CPU * does not need to perform additional invalidation. */ -#define flush_tlb_fix_spurious_fault(vma, address) do { } while (0) +#define flush_tlb_fix_spurious_fault(vma, address, ptep) do { } while (0) /* * ZERO_PAGE is a global shared page that is always zero: used diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h index 791389bf3c12..574fa14ac8b2 100644 --- a/arch/mips/include/asm/pgtable.h +++ b/arch/mips/include/asm/pgtable.h @@ -469,7 +469,8 @@ static inline pgprot_t pgprot_writecombine(pgprot_t _prot) } static inline void flush_tlb_fix_spurious_fault(struct vm_area_struct *vma, - unsigned long address) + unsigned long address, + pte_t *ptep) { } diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush.h b/arch/powerpc/include/asm/book3s/64/tlbflush.h index 2bbc0fcce04a..ff7f0ee179e5 100644 --- a/arch/powerpc/include/asm/book3s/64/tlbflush.h +++ b/arch/powerpc/include/asm/book3s/64/tlbflush.h @@ -121,7 +121,8 @@ static inline void flush_tlb_page(struct vm_area_struct *vma, #define flush_tlb_fix_spurious_fault flush_tlb_fix_spurious_fault static inline void flush_tlb_fix_spurious_fault(struct vm_area_struct *vma, - unsigned long address) + unsigned long address, + pte_t *ptep) { /* * Book3S 64 does not require spurious fault flushes because the PTE diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 2c70b4d1263d..c1f6b46ec555 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1239,7 +1239,8 @@ static inline int pte_allow_rdp(pte_t old, pte_t new) } static inline void flush_tlb_fix_spurious_fault(struct vm_area_struct *vma, - unsigned long address) + unsigned long address, + pte_t *ptep) { /* * RDP might not have propagated the PTE protection reset to all CPUs, @@ -1247,11 +1248,12 @@ static inline void flush_tlb_fix_spurious_fault(struct vm_area_struct *vma, * NOTE: This will also be called when a racing pagetable update on * another thread already installed the correct PTE. Both cases cannot * really be distinguished. - * Therefore, only do the local TLB flush when RDP can be used, to avoid - * unnecessary overhead. + * Therefore, only do the local TLB flush when RDP can be used, and the + * PTE does not have _PAGE_PROTECT set, to avoid unnecessary overhead. + * A local RDP can be used to do the flush. */ - if (MACHINE_HAS_RDP) - asm volatile("ptlb" : : : "memory"); + if (MACHINE_HAS_RDP && !(pte_val(*ptep) & _PAGE_PROTECT)) + __ptep_rdp(address, ptep, 0, 0, 1); } #define flush_tlb_fix_spurious_fault flush_tlb_fix_spurious_fault diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 7425f32e5293..15ae4d6ba476 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -1097,7 +1097,7 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte); } -#define flush_tlb_fix_spurious_fault(vma, address) do { } while (0) +#define flush_tlb_fix_spurious_fault(vma, address, ptep) do { } while (0) #define mk_pmd(page, pgprot) pfn_pmd(page_to_pfn(page), (pgprot)) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 9dc936bc77d1..c5a51481bbb9 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -817,7 +817,7 @@ static inline void arch_swap_restore(swp_entry_t entry, struct folio *folio) #endif #ifndef flush_tlb_fix_spurious_fault -#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address) +#define flush_tlb_fix_spurious_fault(vma, address, ptep) flush_tlb_page(vma, address) #endif /* diff --git a/mm/memory.c b/mm/memory.c index fdc903825981..6285cad1f4fb 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4944,7 +4944,8 @@ static vm_fault_t handle_pte_fault(struct vm_fault *vmf) * with threads. */ if (vmf->flags & FAULT_FLAG_WRITE) - flush_tlb_fix_spurious_fault(vmf->vma, vmf->address); + flush_tlb_fix_spurious_fault(vmf->vma, vmf->address, + vmf->pte); } unlock: pte_unmap_unlock(vmf->pte, vmf->ptl); diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index 90ab721a12a8..d2fc52bffafc 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -69,7 +69,7 @@ int ptep_set_access_flags(struct vm_area_struct *vma, int changed = !pte_same(*ptep, entry); if (changed) { set_pte_at(vma->vm_mm, address, ptep, entry); - flush_tlb_fix_spurious_fault(vma, address); + flush_tlb_fix_spurious_fault(vma, address, ptep); } return changed; } -- cgit v1.2.3 From 82b3aa2681ca92421c4b508e7c390000273c53fe Mon Sep 17 00:00:00 2001 From: Yue Zhao Date: Mon, 6 Mar 2023 23:41:36 +0800 Subject: mm, memcg: Prevent memory.swappiness load/store tearing The knob for cgroup v1 memory controller: memory.swappiness is not protected by any locking so it can be modified while it is used. This is not an actual problem because races are unlikely. But it is better to use [READ|WRITE]_ONCE to prevent compiler from doing anything funky. The access of memcg->swappiness and vm_swappiness is lockless, so both of them can be concurrently set at the same time as we are trying to read them. All occurrences of memcg->swappiness and vm_swappiness are updated with [READ|WRITE]_ONCE. [findns94@gmail.com: v3] Link: https://lkml.kernel.org/r/20230308162555.14195-3-findns94@gmail.com Link: https://lkml.kernel.org/r/20230306154138.3775-3-findns94@gmail.com Signed-off-by: Yue Zhao Acked-by: Michal Hocko Acked-by: Shakeel Butt Acked-by: Roman Gushchin Cc: Johannes Weiner Cc: Matthew Wilcox (Oracle) Cc: Muchun Song Cc: Tang Yizhou Signed-off-by: Andrew Morton --- include/linux/swap.h | 8 ++++---- mm/memcontrol.c | 6 +++--- 2 files changed, 7 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/swap.h b/include/linux/swap.h index d5d0b54e90e8..bfc3b06b5f8f 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -620,18 +620,18 @@ static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg) { /* Cgroup2 doesn't have per-cgroup swappiness */ if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) - return vm_swappiness; + return READ_ONCE(vm_swappiness); /* root ? */ if (mem_cgroup_disabled() || mem_cgroup_is_root(memcg)) - return vm_swappiness; + return READ_ONCE(vm_swappiness); - return memcg->swappiness; + return READ_ONCE(memcg->swappiness); } #else static inline int mem_cgroup_swappiness(struct mem_cgroup *mem) { - return vm_swappiness; + return READ_ONCE(vm_swappiness); } #endif diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 06821e5f7604..1b0112afcad3 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4179,9 +4179,9 @@ static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, return -EINVAL; if (!mem_cgroup_is_root(memcg)) - memcg->swappiness = val; + WRITE_ONCE(memcg->swappiness, val); else - vm_swappiness = val; + WRITE_ONCE(vm_swappiness, val); return 0; } @@ -5353,7 +5353,7 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) #endif page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX); if (parent) { - memcg->swappiness = mem_cgroup_swappiness(parent); + WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent)); memcg->oom_kill_disable = parent->oom_kill_disable; page_counter_init(&memcg->memory, &parent->memory); -- cgit v1.2.3 From 452a8f40728065800b5a5b81f1152e9a16d39656 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 7 Mar 2023 15:31:25 +0100 Subject: mm,jfs: move write_one_page/folio_write_one to jfs The last remaining user of folio_write_one through the write_one_page wrapper is jfs, so move the functionality there and hard code the call to metapage_writepage. Note that the use of the pagecache by the JFS 'metapage' buffer cache is a bit odd, and we could probably do without VM-level dirty tracking at all, but that's a change for another time. Link: https://lkml.kernel.org/r/20230307143125.27778-4-hch@lst.de Signed-off-by: Christoph Hellwig Acked-by: Dave Kleikamp Cc: Changwei Ge Cc: Evgeniy Dushistov Cc: Gang He Cc: Jan Kara Cc: Jan Kara via Ocfs2-devel Cc: Joel Becker Cc: Joseph Qi Cc: Joseph Qi Cc: Jun Piao Cc: Junxiao Bi Cc: Mark Fasheh Cc: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- fs/jfs/jfs_metapage.c | 39 ++++++++++++++++++++++++++++++++++----- include/linux/pagemap.h | 6 ------ mm/page-writeback.c | 40 ---------------------------------------- 3 files changed, 34 insertions(+), 51 deletions(-) (limited to 'include') diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c index 2e8461ce74de..961569c11159 100644 --- a/fs/jfs/jfs_metapage.c +++ b/fs/jfs/jfs_metapage.c @@ -691,6 +691,35 @@ void grab_metapage(struct metapage * mp) unlock_page(mp->page); } +static int metapage_write_one(struct page *page) +{ + struct folio *folio = page_folio(page); + struct address_space *mapping = folio->mapping; + struct writeback_control wbc = { + .sync_mode = WB_SYNC_ALL, + .nr_to_write = folio_nr_pages(folio), + }; + int ret = 0; + + BUG_ON(!folio_test_locked(folio)); + + folio_wait_writeback(folio); + + if (folio_clear_dirty_for_io(folio)) { + folio_get(folio); + ret = metapage_writepage(page, &wbc); + if (ret == 0) + folio_wait_writeback(folio); + folio_put(folio); + } else { + folio_unlock(folio); + } + + if (!ret) + ret = filemap_check_errors(mapping); + return ret; +} + void force_metapage(struct metapage *mp) { struct page *page = mp->page; @@ -700,8 +729,8 @@ void force_metapage(struct metapage *mp) get_page(page); lock_page(page); set_page_dirty(page); - if (write_one_page(page)) - jfs_error(mp->sb, "write_one_page() failed\n"); + if (metapage_write_one(page)) + jfs_error(mp->sb, "metapage_write_one() failed\n"); clear_bit(META_forcewrite, &mp->flag); put_page(page); } @@ -746,9 +775,9 @@ void release_metapage(struct metapage * mp) set_page_dirty(page); if (test_bit(META_sync, &mp->flag)) { clear_bit(META_sync, &mp->flag); - if (write_one_page(page)) - jfs_error(mp->sb, "write_one_page() failed\n"); - lock_page(page); /* write_one_page unlocks the page */ + if (metapage_write_one(page)) + jfs_error(mp->sb, "metapage_write_one() failed\n"); + lock_page(page); } } else if (mp->lsn) /* discard_metapage doesn't remove it */ remove_from_logsync(mp); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 0acb8e1fb7af..853184a46411 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -1066,12 +1066,6 @@ static inline void folio_cancel_dirty(struct folio *folio) bool folio_clear_dirty_for_io(struct folio *folio); bool clear_page_dirty_for_io(struct page *page); void folio_invalidate(struct folio *folio, size_t offset, size_t length); -int __must_check folio_write_one(struct folio *folio); -static inline int __must_check write_one_page(struct page *page) -{ - return folio_write_one(page_folio(page)); -} - int __set_page_dirty_nobuffers(struct page *page); bool noop_dirty_folio(struct address_space *mapping, struct folio *folio); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 516b1aa247e8..db7943999007 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2583,46 +2583,6 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc) return ret; } -/** - * folio_write_one - write out a single folio and wait on I/O. - * @folio: The folio to write. - * - * The folio must be locked by the caller and will be unlocked upon return. - * - * Note that the mapping's AS_EIO/AS_ENOSPC flags will be cleared when this - * function returns. - * - * Return: %0 on success, negative error code otherwise - */ -int folio_write_one(struct folio *folio) -{ - struct address_space *mapping = folio->mapping; - int ret = 0; - struct writeback_control wbc = { - .sync_mode = WB_SYNC_ALL, - .nr_to_write = folio_nr_pages(folio), - }; - - BUG_ON(!folio_test_locked(folio)); - - folio_wait_writeback(folio); - - if (folio_clear_dirty_for_io(folio)) { - folio_get(folio); - ret = mapping->a_ops->writepage(&folio->page, &wbc); - if (ret == 0) - folio_wait_writeback(folio); - folio_put(folio); - } else { - folio_unlock(folio); - } - - if (!ret) - ret = filemap_check_errors(mapping); - return ret; -} -EXPORT_SYMBOL(folio_write_one); - /* * For address_spaces which do not use buffers nor write back. */ -- cgit v1.2.3 From 2c6efe9cf2d7841b75fe38ed1adbd41a90f51ba0 Mon Sep 17 00:00:00 2001 From: Luis Chamberlain Date: Thu, 9 Mar 2023 15:05:45 -0800 Subject: shmem: add support to ignore swap In doing experimentations with shmem having the option to avoid swap becomes a useful mechanism. One of the *raves* about brd over shmem is you can avoid swap, but that's not really a good reason to use brd if we can instead use shmem. Using brd has its own good reasons to exist, but just because "tmpfs" doesn't let you do that is not a great reason to avoid it if we can easily add support for it. I don't add support for reconfiguring incompatible options, but if we really wanted to we can add support for that. To avoid swap we use mapping_set_unevictable() upon inode creation, and put a WARN_ON_ONCE() stop-gap on writepages() for reclaim. Link: https://lkml.kernel.org/r/20230309230545.2930737-7-mcgrof@kernel.org Signed-off-by: Luis Chamberlain Acked-by: Christian Brauner Tested-by: Xin Hao Reviewed-by: Davidlohr Bueso Cc: Adam Manzanares Cc: David Hildenbrand Cc: Davidlohr Bueso Cc: Hugh Dickins Cc: Kees Cook Cc: Matthew Wilcox Cc: Pankaj Raghav Cc: Yosry Ahmed Signed-off-by: Andrew Morton --- Documentation/filesystems/tmpfs.rst | 9 ++++++--- Documentation/mm/unevictable-lru.rst | 2 ++ include/linux/shmem_fs.h | 1 + mm/shmem.c | 28 +++++++++++++++++++++++++++- 4 files changed, 36 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/Documentation/filesystems/tmpfs.rst b/Documentation/filesystems/tmpfs.rst index 1ec9a9f8196b..f18f46be5c0c 100644 --- a/Documentation/filesystems/tmpfs.rst +++ b/Documentation/filesystems/tmpfs.rst @@ -13,7 +13,8 @@ everything stored therein is lost. tmpfs puts everything into the kernel internal caches and grows and shrinks to accommodate the files it contains and is able to swap -unneeded pages out to swap space, and supports THP. +unneeded pages out to swap space, if swap was enabled for the tmpfs +mount. tmpfs also supports THP. tmpfs extends ramfs with a few userspace configurable options listed and explained further below, some of which can be reconfigured dynamically on the @@ -33,8 +34,8 @@ configured in size at initialization and you cannot dynamically resize them. Contrary to brd ramdisks, tmpfs has its own filesystem, it does not rely on the block layer at all. -Since tmpfs lives completely in the page cache and on swap, all tmpfs -pages will be shown as "Shmem" in /proc/meminfo and "Shared" in +Since tmpfs lives completely in the page cache and optionally on swap, +all tmpfs pages will be shown as "Shmem" in /proc/meminfo and "Shared" in free(1). Notice that these counters also include shared memory (shmem, see ipcs(1)). The most reliable way to get the count is using df(1) and du(1). @@ -83,6 +84,8 @@ nr_inodes The maximum number of inodes for this instance. The default is half of the number of your physical RAM pages, or (on a machine with highmem) the number of lowmem RAM pages, whichever is the lower. +noswap Disables swap. Remounts must respect the original settings. + By default swap is enabled. ========= ============================================================ These parameters accept a suffix k, m or g for kilo, mega and giga and diff --git a/Documentation/mm/unevictable-lru.rst b/Documentation/mm/unevictable-lru.rst index 92ac5dca420c..d5ac8511eb67 100644 --- a/Documentation/mm/unevictable-lru.rst +++ b/Documentation/mm/unevictable-lru.rst @@ -42,6 +42,8 @@ The unevictable list addresses the following classes of unevictable pages: * Those owned by ramfs. + * Those owned by tmpfs with the noswap mount option. + * Those mapped into SHM_LOCK'd shared memory regions. * Those mapped into VM_LOCKED [mlock()ed] VMAs. diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index 103d1000a5a2..50bf82b36995 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -45,6 +45,7 @@ struct shmem_sb_info { kuid_t uid; /* Mount uid for root directory */ kgid_t gid; /* Mount gid for root directory */ bool full_inums; /* If i_ino should be uint or ino_t */ + bool noswap; /* ignores VM reclaim / swap requests */ ino_t next_ino; /* The next per-sb inode number to use */ ino_t __percpu *ino_batch; /* The next per-cpu inode number to use */ struct mempolicy *mpol; /* default memory policy for mappings */ diff --git a/mm/shmem.c b/mm/shmem.c index 7751c136eadb..787e83791eb5 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -116,10 +116,12 @@ struct shmem_options { bool full_inums; int huge; int seen; + bool noswap; #define SHMEM_SEEN_BLOCKS 1 #define SHMEM_SEEN_INODES 2 #define SHMEM_SEEN_HUGE 4 #define SHMEM_SEEN_INUMS 8 +#define SHMEM_SEEN_NOSWAP 16 }; #ifdef CONFIG_TMPFS @@ -1334,6 +1336,7 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) struct address_space *mapping = folio->mapping; struct inode *inode = mapping->host; struct shmem_inode_info *info = SHMEM_I(inode); + struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb); swp_entry_t swap; pgoff_t index; @@ -1347,7 +1350,7 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) if (WARN_ON_ONCE(!wbc->for_reclaim)) goto redirty; - if (WARN_ON_ONCE(info->flags & VM_LOCKED)) + if (WARN_ON_ONCE((info->flags & VM_LOCKED) || sbinfo->noswap)) goto redirty; if (!total_swap_pages) @@ -2372,6 +2375,8 @@ static struct inode *shmem_get_inode(struct mnt_idmap *idmap, struct super_block shmem_set_inode_flags(inode, info->fsflags); INIT_LIST_HEAD(&info->shrinklist); INIT_LIST_HEAD(&info->swaplist); + if (sbinfo->noswap) + mapping_set_unevictable(inode->i_mapping); simple_xattrs_init(&info->xattrs); cache_no_acl(inode); mapping_set_large_folios(inode->i_mapping); @@ -3459,6 +3464,7 @@ enum shmem_param { Opt_uid, Opt_inode32, Opt_inode64, + Opt_noswap, }; static const struct constant_table shmem_param_enums_huge[] = { @@ -3480,6 +3486,7 @@ const struct fs_parameter_spec shmem_fs_parameters[] = { fsparam_u32 ("uid", Opt_uid), fsparam_flag ("inode32", Opt_inode32), fsparam_flag ("inode64", Opt_inode64), + fsparam_flag ("noswap", Opt_noswap), {} }; @@ -3563,6 +3570,10 @@ static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param) ctx->full_inums = true; ctx->seen |= SHMEM_SEEN_INUMS; break; + case Opt_noswap: + ctx->noswap = true; + ctx->seen |= SHMEM_SEEN_NOSWAP; + break; } return 0; @@ -3661,6 +3672,14 @@ static int shmem_reconfigure(struct fs_context *fc) err = "Current inum too high to switch to 32-bit inums"; goto out; } + if ((ctx->seen & SHMEM_SEEN_NOSWAP) && ctx->noswap && !sbinfo->noswap) { + err = "Cannot disable swap on remount"; + goto out; + } + if (!(ctx->seen & SHMEM_SEEN_NOSWAP) && !ctx->noswap && sbinfo->noswap) { + err = "Cannot enable swap on remount if it was disabled on first mount"; + goto out; + } if (ctx->seen & SHMEM_SEEN_HUGE) sbinfo->huge = ctx->huge; @@ -3681,6 +3700,10 @@ static int shmem_reconfigure(struct fs_context *fc) sbinfo->mpol = ctx->mpol; /* transfers initial ref */ ctx->mpol = NULL; } + + if (ctx->noswap) + sbinfo->noswap = true; + raw_spin_unlock(&sbinfo->stat_lock); mpol_put(mpol); return 0; @@ -3735,6 +3758,8 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root) seq_printf(seq, ",huge=%s", shmem_format_huge(sbinfo->huge)); #endif shmem_show_mpol(seq, sbinfo->mpol); + if (sbinfo->noswap) + seq_printf(seq, ",noswap"); return 0; } @@ -3778,6 +3803,7 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc) ctx->inodes = shmem_default_max_inodes(); if (!(ctx->seen & SHMEM_SEEN_INUMS)) ctx->full_inums = IS_ENABLED(CONFIG_TMPFS_INODE64); + sbinfo->noswap = ctx->noswap; } else { sb->s_flags |= SB_NOUSER; } -- cgit v1.2.3 From 7eb16f23b9a415f062db22739e59bb144e0b24ab Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Fri, 10 Mar 2023 17:29:05 +0100 Subject: io-mapping: don't disable preempt on RT in io_mapping_map_atomic_wc(). io_mapping_map_atomic_wc() disables preemption and pagefaults for historical reasons. The conversion to io_mapping_map_local_wc(), which only disables migration, cannot be done wholesale because quite some call sites need to be updated to accommodate with the changed semantics. On PREEMPT_RT enabled kernels the io_mapping_map_atomic_wc() semantics are problematic due to the implicit disabling of preemption which makes it impossible to acquire 'sleeping' spinlocks within the mapped atomic sections. PREEMPT_RT replaces the preempt_disable() with a migrate_disable() for more than a decade. It could be argued that this is a justification to do this unconditionally, but PREEMPT_RT covers only a limited number of architectures and it disables some functionality which limits the coverage further. Limit the replacement to PREEMPT_RT for now. This is also done kmap_atomic(). Link: https://lkml.kernel.org/r/20230310162905.O57Pj7hh@linutronix.de Signed-off-by: Sebastian Andrzej Siewior Reported-by: Richard Weinberger Link: https://lore.kernel.org/CAFLxGvw0WMxaMqYqJ5WgvVSbKHq2D2xcXTOgMCpgq9nDC-MWTQ@mail.gmail.com Cc: Thomas Gleixner Signed-off-by: Andrew Morton --- include/linux/io-mapping.h | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h index 09d4f17c8d3b..7376c1df9c90 100644 --- a/include/linux/io-mapping.h +++ b/include/linux/io-mapping.h @@ -69,7 +69,10 @@ io_mapping_map_atomic_wc(struct io_mapping *mapping, BUG_ON(offset >= mapping->size); phys_addr = mapping->base + offset; - preempt_disable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_disable(); + else + migrate_disable(); pagefault_disable(); return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot); } @@ -79,7 +82,10 @@ io_mapping_unmap_atomic(void __iomem *vaddr) { kunmap_local_indexed((void __force *)vaddr); pagefault_enable(); - preempt_enable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_enable(); + else + migrate_enable(); } static inline void __iomem * @@ -162,7 +168,10 @@ static inline void __iomem * io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) { - preempt_disable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_disable(); + else + migrate_disable(); pagefault_disable(); return io_mapping_map_wc(mapping, offset, PAGE_SIZE); } @@ -172,7 +181,10 @@ io_mapping_unmap_atomic(void __iomem *vaddr) { io_mapping_unmap(vaddr); pagefault_enable(); - preempt_enable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_enable(); + else + migrate_enable(); } static inline void __iomem * -- cgit v1.2.3 From 0a54864f8dfb64b64c84c9db6ff70e0e93690a33 Mon Sep 17 00:00:00 2001 From: Peter Collingbourne Date: Thu, 9 Mar 2023 20:29:14 -0800 Subject: kasan: remove PG_skip_kasan_poison flag Code inspection reveals that PG_skip_kasan_poison is redundant with kasantag, because the former is intended to be set iff the latter is the match-all tag. It can also be observed that it's basically pointless to poison pages which have kasantag=0, because any pages with this tag would have been pointed to by pointers with match-all tags, so poisoning the pages would have little to no effect in terms of bug detection. Therefore, change the condition in should_skip_kasan_poison() to check kasantag instead, and remove PG_skip_kasan_poison and associated flags. Link: https://lkml.kernel.org/r/20230310042914.3805818-3-pcc@google.com Link: https://linux-review.googlesource.com/id/I57f825f2eaeaf7e8389d6cf4597c8a5821359838 Signed-off-by: Peter Collingbourne Reviewed-by: Andrey Konovalov Cc: Andrey Ryabinin Cc: Catalin Marinas Cc: Evgenii Stepanov Cc: Vincenzo Frascino Cc: Will Deacon Signed-off-by: Andrew Morton --- include/linux/gfp_types.h | 30 +++++++--------- include/linux/page-flags.h | 9 ----- include/trace/events/mmflags.h | 13 ++----- mm/kasan/hw_tags.c | 2 +- mm/page_alloc.c | 81 ++++++++++++++++-------------------------- mm/vmalloc.c | 2 +- 6 files changed, 47 insertions(+), 90 deletions(-) (limited to 'include') diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h index 5088637fe5c2..6583a58670c5 100644 --- a/include/linux/gfp_types.h +++ b/include/linux/gfp_types.h @@ -47,16 +47,14 @@ typedef unsigned int __bitwise gfp_t; #define ___GFP_ACCOUNT 0x400000u #define ___GFP_ZEROTAGS 0x800000u #ifdef CONFIG_KASAN_HW_TAGS -#define ___GFP_SKIP_ZERO 0x1000000u -#define ___GFP_SKIP_KASAN_UNPOISON 0x2000000u -#define ___GFP_SKIP_KASAN_POISON 0x4000000u +#define ___GFP_SKIP_ZERO 0x1000000u +#define ___GFP_SKIP_KASAN 0x2000000u #else -#define ___GFP_SKIP_ZERO 0 -#define ___GFP_SKIP_KASAN_UNPOISON 0 -#define ___GFP_SKIP_KASAN_POISON 0 +#define ___GFP_SKIP_ZERO 0 +#define ___GFP_SKIP_KASAN 0 #endif #ifdef CONFIG_LOCKDEP -#define ___GFP_NOLOCKDEP 0x8000000u +#define ___GFP_NOLOCKDEP 0x4000000u #else #define ___GFP_NOLOCKDEP 0 #endif @@ -234,25 +232,24 @@ typedef unsigned int __bitwise gfp_t; * memory tags at the same time as zeroing memory has minimal additional * performace impact. * - * %__GFP_SKIP_KASAN_UNPOISON makes KASAN skip unpoisoning on page allocation. - * Only effective in HW_TAGS mode. - * - * %__GFP_SKIP_KASAN_POISON makes KASAN skip poisoning on page deallocation. - * Typically, used for userspace pages. Only effective in HW_TAGS mode. + * %__GFP_SKIP_KASAN makes KASAN skip unpoisoning on page allocation. + * Used for userspace and vmalloc pages; the latter are unpoisoned by + * kasan_unpoison_vmalloc instead. For userspace pages, results in + * poisoning being skipped as well, see should_skip_kasan_poison for + * details. Only effective in HW_TAGS mode. */ #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN) #define __GFP_COMP ((__force gfp_t)___GFP_COMP) #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO) #define __GFP_ZEROTAGS ((__force gfp_t)___GFP_ZEROTAGS) #define __GFP_SKIP_ZERO ((__force gfp_t)___GFP_SKIP_ZERO) -#define __GFP_SKIP_KASAN_UNPOISON ((__force gfp_t)___GFP_SKIP_KASAN_UNPOISON) -#define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON) +#define __GFP_SKIP_KASAN ((__force gfp_t)___GFP_SKIP_KASAN) /* Disable lockdep for GFP context tracking */ #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP) /* Room for N __GFP_FOO bits */ -#define __GFP_BITS_SHIFT (27 + IS_ENABLED(CONFIG_LOCKDEP)) +#define __GFP_BITS_SHIFT (26 + IS_ENABLED(CONFIG_LOCKDEP)) #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) /** @@ -335,8 +332,7 @@ typedef unsigned int __bitwise gfp_t; #define GFP_DMA __GFP_DMA #define GFP_DMA32 __GFP_DMA32 #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM) -#define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE | \ - __GFP_SKIP_KASAN_POISON | __GFP_SKIP_KASAN_UNPOISON) +#define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE | __GFP_SKIP_KASAN) #define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \ __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM) #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 57287102c5bd..dcda20c47b8f 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -135,9 +135,6 @@ enum pageflags { #ifdef CONFIG_ARCH_USES_PG_ARCH_X PG_arch_2, PG_arch_3, -#endif -#ifdef CONFIG_KASAN_HW_TAGS - PG_skip_kasan_poison, #endif __NR_PAGEFLAGS, @@ -594,12 +591,6 @@ TESTCLEARFLAG(Young, young, PF_ANY) PAGEFLAG(Idle, idle, PF_ANY) #endif -#ifdef CONFIG_KASAN_HW_TAGS -PAGEFLAG(SkipKASanPoison, skip_kasan_poison, PF_HEAD) -#else -PAGEFLAG_FALSE(SkipKASanPoison, skip_kasan_poison) -#endif - /* * PageReported() is used to track reported free pages within the Buddy * allocator. We can use the non-atomic version of the test and set diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h index b28218b7998e..b63e7c0fbbe5 100644 --- a/include/trace/events/mmflags.h +++ b/include/trace/events/mmflags.h @@ -55,8 +55,7 @@ #ifdef CONFIG_KASAN_HW_TAGS #define __def_gfpflag_names_kasan , \ gfpflag_string(__GFP_SKIP_ZERO), \ - gfpflag_string(__GFP_SKIP_KASAN_POISON), \ - gfpflag_string(__GFP_SKIP_KASAN_UNPOISON) + gfpflag_string(__GFP_SKIP_KASAN) #else #define __def_gfpflag_names_kasan #endif @@ -96,13 +95,6 @@ #define IF_HAVE_PG_ARCH_X(_name) #endif -#ifdef CONFIG_KASAN_HW_TAGS -#define IF_HAVE_PG_SKIP_KASAN_POISON(_name) \ - ,{1UL << PG_##_name, __stringify(_name)} -#else -#define IF_HAVE_PG_SKIP_KASAN_POISON(_name) -#endif - #define DEF_PAGEFLAG_NAME(_name) { 1UL << PG_##_name, __stringify(_name) } #define __def_pageflag_names \ @@ -133,8 +125,7 @@ IF_HAVE_PG_HWPOISON(hwpoison) \ IF_HAVE_PG_IDLE(idle) \ IF_HAVE_PG_IDLE(young) \ IF_HAVE_PG_ARCH_X(arch_2) \ -IF_HAVE_PG_ARCH_X(arch_3) \ -IF_HAVE_PG_SKIP_KASAN_POISON(skip_kasan_poison) +IF_HAVE_PG_ARCH_X(arch_3) #define show_page_flags(flags) \ (flags) ? __print_flags(flags, "|", \ diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c index d1bcb0205327..bb4f56e5bdec 100644 --- a/mm/kasan/hw_tags.c +++ b/mm/kasan/hw_tags.c @@ -318,7 +318,7 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size, * Thus, for VM_ALLOC mappings, hardware tag-based KASAN only tags * the first virtual mapping, which is created by vmalloc(). * Tagging the page_alloc memory backing that vmalloc() allocation is - * skipped, see ___GFP_SKIP_KASAN_UNPOISON. + * skipped, see ___GFP_SKIP_KASAN. * * For non-VM_ALLOC allocations, page_alloc memory is tagged as usual. */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a109444e9f44..3737f9d58f5f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -112,17 +112,6 @@ typedef int __bitwise fpi_t; */ #define FPI_TO_TAIL ((__force fpi_t)BIT(1)) -/* - * Don't poison memory with KASAN (only for the tag-based modes). - * During boot, all non-reserved memblock memory is exposed to page_alloc. - * Poisoning all that memory lengthens boot time, especially on systems with - * large amount of RAM. This flag is used to skip that poisoning. - * This is only done for the tag-based KASAN modes, as those are able to - * detect memory corruptions with the memory tags assigned by default. - * All memory allocated normally after boot gets poisoned as usual. - */ -#define FPI_SKIP_KASAN_POISON ((__force fpi_t)BIT(2)) - /* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */ static DEFINE_MUTEX(pcp_batch_high_lock); #define MIN_PERCPU_PAGELIST_HIGH_FRACTION (8) @@ -1370,13 +1359,19 @@ out: /* * Skip KASAN memory poisoning when either: * - * 1. Deferred memory initialization has not yet completed, - * see the explanation below. - * 2. Skipping poisoning is requested via FPI_SKIP_KASAN_POISON, - * see the comment next to it. - * 3. Skipping poisoning is requested via __GFP_SKIP_KASAN_POISON, - * see the comment next to it. - * 4. The allocation is excluded from being checked due to sampling, + * 1. For generic KASAN: deferred memory initialization has not yet completed. + * Tag-based KASAN modes skip pages freed via deferred memory initialization + * using page tags instead (see below). + * 2. For tag-based KASAN modes: the page has a match-all KASAN tag, indicating + * that error detection is disabled for accesses via the page address. + * + * Pages will have match-all tags in the following circumstances: + * + * 1. Pages are being initialized for the first time, including during deferred + * memory init; see the call to page_kasan_tag_reset in __init_single_page. + * 2. The allocation was not unpoisoned due to __GFP_SKIP_KASAN, with the + * exception of pages unpoisoned by kasan_unpoison_vmalloc. + * 3. The allocation was excluded from being checked due to sampling, * see the call to kasan_unpoison_pages. * * Poisoning pages during deferred memory init will greatly lengthen the @@ -1392,10 +1387,10 @@ out: */ static inline bool should_skip_kasan_poison(struct page *page, fpi_t fpi_flags) { - return deferred_pages_enabled() || - (!IS_ENABLED(CONFIG_KASAN_GENERIC) && - (fpi_flags & FPI_SKIP_KASAN_POISON)) || - PageSkipKASanPoison(page); + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + return deferred_pages_enabled(); + + return page_kasan_tag(page) == 0xff; } static void kernel_init_pages(struct page *page, int numpages) @@ -1730,7 +1725,7 @@ void __free_pages_core(struct page *page, unsigned int order) * Bypass PCP and place fresh pages right to the tail, primarily * relevant for memory onlining. */ - __free_pages_ok(page, order, FPI_TO_TAIL | FPI_SKIP_KASAN_POISON); + __free_pages_ok(page, order, FPI_TO_TAIL); } #ifdef CONFIG_NUMA @@ -2396,9 +2391,9 @@ static inline bool should_skip_kasan_unpoison(gfp_t flags) /* * With hardware tag-based KASAN enabled, skip if this has been - * requested via __GFP_SKIP_KASAN_UNPOISON. + * requested via __GFP_SKIP_KASAN. */ - return flags & __GFP_SKIP_KASAN_UNPOISON; + return flags & __GFP_SKIP_KASAN; } static inline bool should_skip_init(gfp_t flags) @@ -2417,7 +2412,6 @@ inline void post_alloc_hook(struct page *page, unsigned int order, bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags) && !should_skip_init(gfp_flags); bool zero_tags = init && (gfp_flags & __GFP_ZEROTAGS); - bool reset_tags = true; int i; set_page_private(page, 0); @@ -2451,37 +2445,22 @@ inline void post_alloc_hook(struct page *page, unsigned int order, /* Take note that memory was initialized by the loop above. */ init = false; } - if (!should_skip_kasan_unpoison(gfp_flags)) { - /* Try unpoisoning (or setting tags) and initializing memory. */ - if (kasan_unpoison_pages(page, order, init)) { - /* Take note that memory was initialized by KASAN. */ - if (kasan_has_integrated_init()) - init = false; - /* Take note that memory tags were set by KASAN. */ - reset_tags = false; - } else { - /* - * KASAN decided to exclude this allocation from being - * (un)poisoned due to sampling. Make KASAN skip - * poisoning when the allocation is freed. - */ - SetPageSkipKASanPoison(page); - } - } - /* - * If memory tags have not been set by KASAN, reset the page tags to - * ensure page_address() dereferencing does not fault. - */ - if (reset_tags) { + if (!should_skip_kasan_unpoison(gfp_flags) && + kasan_unpoison_pages(page, order, init)) { + /* Take note that memory was initialized by KASAN. */ + if (kasan_has_integrated_init()) + init = false; + } else { + /* + * If memory tags have not been set by KASAN, reset the page + * tags to ensure page_address() dereferencing does not fault. + */ for (i = 0; i != 1 << order; ++i) page_kasan_tag_reset(page + i); } /* If memory is still not initialized, initialize it now. */ if (init) kernel_init_pages(page, 1 << order); - /* Propagate __GFP_SKIP_KASAN_POISON to page flags. */ - if (kasan_hw_tags_enabled() && (gfp_flags & __GFP_SKIP_KASAN_POISON)) - SetPageSkipKASanPoison(page); set_page_owner(page, order, gfp_flags); page_table_check_alloc(page, order); diff --git a/mm/vmalloc.c b/mm/vmalloc.c index bef6cf2b4d46..5e60e9792cbf 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -3188,7 +3188,7 @@ again: * pages backing VM_ALLOC mapping. Memory is instead * poisoned and zeroed by kasan_unpoison_vmalloc(). */ - gfp_mask |= __GFP_SKIP_KASAN_UNPOISON | __GFP_SKIP_ZERO; + gfp_mask |= __GFP_SKIP_KASAN | __GFP_SKIP_ZERO; } /* Take note that the mapping is PAGE_KERNEL. */ -- cgit v1.2.3 From dcc1be119071f034f3123d3c618d2ef70c80125e Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Mon, 13 Mar 2023 12:27:14 +0000 Subject: mm: prefer xxx_page() alloc/free functions for order-0 pages Update instances of alloc_pages(..., 0), __get_free_pages(..., 0) and __free_pages(..., 0) to use alloc_page(), __get_free_page() and __free_page() respectively in core code. Link: https://lkml.kernel.org/r/50c48ca4789f1da2a65795f2346f5ae3eff7d665.1678710232.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes Reviewed-by: David Hildenbrand Reviewed-by: Mike Rapoport (IBM) Acked-by: Mel Gorman Cc: Arnd Bergmann Cc: Christoph Hellwig Cc: Nicholas Piggin Cc: Peter Zijlstra Cc: Uladzislau Rezki (Sony) Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/asm-generic/pgalloc.h | 4 ++-- mm/debug_vm_pgtable.c | 4 ++-- mm/hugetlb_vmemmap.c | 2 +- mm/mmu_gather.c | 2 +- mm/page_alloc.c | 2 +- mm/vmalloc.c | 2 +- 6 files changed, 8 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h index 977bea16cf1b..a7cf825befae 100644 --- a/include/asm-generic/pgalloc.h +++ b/include/asm-generic/pgalloc.h @@ -123,11 +123,11 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr) if (mm == &init_mm) gfp = GFP_PGTABLE_KERNEL; - page = alloc_pages(gfp, 0); + page = alloc_page(gfp); if (!page) return NULL; if (!pgtable_pmd_page_ctor(page)) { - __free_pages(page, 0); + __free_page(page); return NULL; } return (pmd_t *)page_address(page); diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 7887cc2b75bf..4362021b1ce7 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -1048,7 +1048,7 @@ static void __init destroy_args(struct pgtable_debug_args *args) if (args->pte_pfn != ULONG_MAX) { page = pfn_to_page(args->pte_pfn); - __free_pages(page, 0); + __free_page(page); args->pte_pfn = ULONG_MAX; } @@ -1290,7 +1290,7 @@ static int __init init_args(struct pgtable_debug_args *args) } } - page = alloc_pages(GFP_KERNEL, 0); + page = alloc_page(GFP_KERNEL); if (page) args->pte_pfn = page_to_pfn(page); diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index a15cc56cf70a..1198064f80eb 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -400,7 +400,7 @@ static int alloc_vmemmap_page_list(unsigned long start, unsigned long end, return 0; out: list_for_each_entry_safe(page, next, list, lru) - __free_pages(page, 0); + __free_page(page); return -ENOMEM; } diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c index 2b93cf6ac9ae..ea9683e12936 100644 --- a/mm/mmu_gather.c +++ b/mm/mmu_gather.c @@ -32,7 +32,7 @@ static bool tlb_next_batch(struct mmu_gather *tlb) if (tlb->batch_count == MAX_GATHER_BATCH_COUNT) return false; - batch = (void *)__get_free_pages(GFP_NOWAIT | __GFP_NOWARN, 0); + batch = (void *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN); if (!batch) return false; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 3737f9d58f5f..0936bde1d486 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5558,7 +5558,7 @@ EXPORT_SYMBOL(__get_free_pages); unsigned long get_zeroed_page(gfp_t gfp_mask) { - return __get_free_pages(gfp_mask | __GFP_ZERO, 0); + return __get_free_page(gfp_mask | __GFP_ZERO); } EXPORT_SYMBOL(get_zeroed_page); diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 5e60e9792cbf..978194dc2bb8 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2739,7 +2739,7 @@ void vfree(const void *addr) * High-order allocs for huge vmallocs are split, so * can be freed as an array of order-0 allocations */ - __free_pages(page, 0); + __free_page(page); cond_resched(); } atomic_long_sub(vm->nr_pages, &nr_vmalloc_pages); -- cgit v1.2.3 From 42c9db39704839eeb77b27db4c1d57bfa2a54a5b Mon Sep 17 00:00:00 2001 From: Qi Zheng Date: Mon, 13 Mar 2023 19:28:12 +0800 Subject: mm: vmscan: add a map_nr_max field to shrinker_info MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch series "make slab shrink lockless", v5. This patch series aims to make slab shrink lockless. 1. Background ============= On our servers, we often find the following system cpu hotspots: 52.22% [kernel] [k] down_read_trylock 19.60% [kernel] [k] up_read 8.86% [kernel] [k] shrink_slab 2.44% [kernel] [k] idr_find 1.25% [kernel] [k] count_shadow_nodes 1.18% [kernel] [k] shrink lruvec 0.71% [kernel] [k] mem_cgroup_iter 0.71% [kernel] [k] shrink_node 0.55% [kernel] [k] find_next_bit And we used bpftrace to capture its calltrace as follows: @[ down_read_trylock+1 shrink_slab+128 shrink_node+371 do_try_to_free_pages+232 try_to_free_pages+243 _alloc_pages_slowpath+771 _alloc_pages_nodemask+702 pagecache_get_page+255 filemap_fault+1361 ext4_filemap_fault+44 __do_fault+76 handle_mm_fault+3543 do_user_addr_fault+442 do_page_fault+48 page_fault+62 ]: 1161690 @[ down_read_trylock+1 shrink_slab+128 shrink_node+371 balance_pgdat+690 kswapd+389 kthread+246 ret_from_fork+31 ]: 8424884 @[ down_read_trylock+1 shrink_slab+128 shrink_node+371 do_try_to_free_pages+232 try_to_free_pages+243 __alloc_pages_slowpath+771 __alloc_pages_nodemask+702 __do_page_cache_readahead+244 filemap_fault+1674 ext4_filemap_fault+44 __do_fault+76 handle_mm_fault+3543 do_user_addr_fault+442 do_page_fault+48 page_fault+62 ]: 20917631 We can see that down_read_trylock() of shrinker_rwsem is being called with high frequency at that time. Because of the poor multicore scalability of atomic operations, this can lead to a significant drop in IPC (instructions per cycle). And more, the shrinker_rwsem is a global read-write lock in shrinkers subsystem, which protects most operations such as slab shrink, registration and unregistration of shrinkers, etc. This can easily cause problems in the following cases. 1) When the memory pressure is high and there are many filesystems mounted or unmounted at the same time, slab shrink will be affected (down_read_trylock() failed). Such as the real workload mentioned by Kirill Tkhai: ``` One of the real workloads from my experience is start of an overcommitted node containing many starting containers after node crash (or many resuming containers after reboot for kernel update). In these cases memory pressure is huge, and the node goes round in long reclaim. ``` 2) If a shrinker is blocked (such as the case mentioned in [1]) and a writer comes in (such as mount a fs), then this writer will be blocked and cause all subsequent shrinker-related operations to be blocked. [1]. https://lore.kernel.org/lkml/20191129214541.3110-1-ptikhomirov@virtuozzo.com/ All the above cases can be solved by replacing the shrinker_rwsem trylocks with SRCU. 2. Survey ========= Before doing the code implementation, I found that there were many similar submissions in the community: a. Davidlohr Bueso submitted a patch in 2015. Subject: [PATCH -next v2] mm: srcu-ify shrinkers Link: https://lore.kernel.org/all/1437080113.3596.2.camel@stgolabs.net/ Result: It was finally merged into the linux-next branch, but failed on arm allnoconfig (without CONFIG_SRCU) b. Tetsuo Handa submitted a patchset in 2017. Subject: [PATCH 1/2] mm,vmscan: Kill global shrinker lock. Link: https://lore.kernel.org/lkml/1510609063-3327-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp/ Result: Finally chose to use the current simple way (break when rwsem_is_contended()). And Christoph Hellwig suggested to using SRCU, but SRCU was not unconditionally enabled at the time. c. Kirill Tkhai submitted a patchset in 2018. Subject: [PATCH RFC 00/10] Introduce lockless shrink_slab() Link: https://lore.kernel.org/lkml/153365347929.19074.12509495712735843805.stgit@localhost.localdomain/ Result: At that time, SRCU was not unconditionally enabled, and there were some objections to enabling SRCU. Later, because Kirill's focus was moved to other things, this patchset was not continued to be updated. d. Sultan Alsawaf submitted a patch in 2021. Subject: [PATCH] mm: vmscan: Replace shrinker_rwsem trylocks with SRCU protection Link: https://lore.kernel.org/lkml/20210927074823.5825-1-sultan@kerneltoast.com/ Result: Rejected because SRCU was not unconditionally enabled. We can find that almost all these historical commits were abandoned because SRCU was not unconditionally enabled. But now SRCU has been unconditionally enable by Paul E. McKenney in 2023 [2], so it's time to replace shrinker_rwsem trylocks with SRCU. [2] https://lore.kernel.org/lkml/20230105003759.GA1769545@paulmck-ThinkPad-P17-Gen-1/ 3. Reproduction and testing =========================== We can reproduce the down_read_trylock() hotspot through the following script: ``` #!/bin/bash DIR="/root/shrinker/memcg/mnt" do_create() { mkdir -p /sys/fs/cgroup/memory/test mkdir -p /sys/fs/cgroup/perf_event/test echo 4G > /sys/fs/cgroup/memory/test/memory.limit_in_bytes for i in `seq 0 $1`; do mkdir -p /sys/fs/cgroup/memory/test/$i; echo $$ > /sys/fs/cgroup/memory/test/$i/cgroup.procs; echo $$ > /sys/fs/cgroup/perf_event/test/cgroup.procs; mkdir -p $DIR/$i; done } do_mount() { for i in `seq $1 $2`; do mount -t tmpfs $i $DIR/$i; done } do_touch() { for i in `seq $1 $2`; do echo $$ > /sys/fs/cgroup/memory/test/$i/cgroup.procs; echo $$ > /sys/fs/cgroup/perf_event/test/cgroup.procs; dd if=/dev/zero of=$DIR/$i/file$i bs=1M count=1 & done } case "$1" in touch) do_touch $2 $3 ;; test) do_create 4000 do_mount 0 4000 do_touch 0 3000 ;; *) exit 1 ;; esac ``` Save the above script, then run test and touch commands. Then we can use the following perf command to view hotspots: perf top -U -F 999 1) Before applying this patchset: 32.31% [kernel] [k] down_read_trylock 19.40% [kernel] [k] pv_native_safe_halt 16.24% [kernel] [k] up_read 15.70% [kernel] [k] shrink_slab 4.69% [kernel] [k] _find_next_bit 2.62% [kernel] [k] shrink_node 1.78% [kernel] [k] shrink_lruvec 0.76% [kernel] [k] do_shrink_slab 2) After applying this patchset: 27.83% [kernel] [k] _find_next_bit 16.97% [kernel] [k] shrink_slab 15.82% [kernel] [k] pv_native_safe_halt 9.58% [kernel] [k] shrink_node 8.31% [kernel] [k] shrink_lruvec 5.64% [kernel] [k] do_shrink_slab 3.88% [kernel] [k] mem_cgroup_iter At the same time, we use the following perf command to capture IPC information: perf stat -e cycles,instructions -G test -a --repeat 5 -- sleep 10 1) Before applying this patchset: Performance counter stats for 'system wide' (5 runs): 454187219766 cycles test ( +- 1.84% ) 78896433101 instructions test # 0.17 insn per cycle ( +- 0.44% ) 10.0020430 +- 0.0000366 seconds time elapsed ( +- 0.00% ) 2) After applying this patchset: Performance counter stats for 'system wide' (5 runs): 841954709443 cycles test ( +- 15.80% ) (98.69%) 527258677936 instructions test # 0.63 insn per cycle ( +- 15.11% ) (98.68%) 10.01064 +- 0.00831 seconds time elapsed ( +- 0.08% ) We can see that IPC drops very seriously when calling down_read_trylock() at high frequency. After using SRCU, the IPC is at a normal level. This patch (of 8): To prepare for the subsequent lockless memcg slab shrink, add a map_nr_max field to struct shrinker_info to records its own real shrinker_nr_max. Link: https://lkml.kernel.org/r/20230313112819.38938-1-zhengqi.arch@bytedance.com Link: https://lkml.kernel.org/r/20230313112819.38938-2-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Suggested-by: Kirill Tkhai Acked-by: Vlastimil Babka Acked-by: Kirill Tkhai Acked-by: Roman Gushchin Cc: Christian König Cc: David Hildenbrand Cc: Davidlohr Bueso Cc: Johannes Weiner Cc: Michal Hocko Cc: Muchun Song Cc: Paul E. McKenney Cc: Qi Zheng Cc: Shakeel Butt Cc: Sultan Alsawaf Cc: Tetsuo Handa Cc: Yang Shi Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 1 + mm/vmscan.c | 35 ++++++++++++++++++----------------- 2 files changed, 19 insertions(+), 17 deletions(-) (limited to 'include') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index b6eda2ab205d..aa69ea98e2d8 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -97,6 +97,7 @@ struct shrinker_info { struct rcu_head rcu; atomic_long_t *nr_deferred; unsigned long *map; + int map_nr_max; }; struct lruvec_stats_percpu { diff --git a/mm/vmscan.c b/mm/vmscan.c index 9414226218f0..9a2a6301052c 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -226,7 +226,8 @@ static struct shrinker_info *shrinker_info_protected(struct mem_cgroup *memcg, static int expand_one_shrinker_info(struct mem_cgroup *memcg, int map_size, int defer_size, - int old_map_size, int old_defer_size) + int old_map_size, int old_defer_size, + int new_nr_max) { struct shrinker_info *new, *old; struct mem_cgroup_per_node *pn; @@ -240,12 +241,17 @@ static int expand_one_shrinker_info(struct mem_cgroup *memcg, if (!old) return 0; + /* Already expanded this shrinker_info */ + if (new_nr_max <= old->map_nr_max) + continue; + new = kvmalloc_node(sizeof(*new) + size, GFP_KERNEL, nid); if (!new) return -ENOMEM; new->nr_deferred = (atomic_long_t *)(new + 1); new->map = (void *)new->nr_deferred + defer_size; + new->map_nr_max = new_nr_max; /* map: set all old bits, clear all new bits */ memset(new->map, (int)0xff, old_map_size); @@ -295,6 +301,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) } info->nr_deferred = (atomic_long_t *)(info + 1); info->map = (void *)info->nr_deferred + defer_size; + info->map_nr_max = shrinker_nr_max; rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_info, info); } up_write(&shrinker_rwsem); @@ -302,23 +309,14 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) return ret; } -static inline bool need_expand(int nr_max) -{ - return round_up(nr_max, BITS_PER_LONG) > - round_up(shrinker_nr_max, BITS_PER_LONG); -} - static int expand_shrinker_info(int new_id) { int ret = 0; - int new_nr_max = new_id + 1; + int new_nr_max = round_up(new_id + 1, BITS_PER_LONG); int map_size, defer_size = 0; int old_map_size, old_defer_size = 0; struct mem_cgroup *memcg; - if (!need_expand(new_nr_max)) - goto out; - if (!root_mem_cgroup) goto out; @@ -332,7 +330,8 @@ static int expand_shrinker_info(int new_id) memcg = mem_cgroup_iter(NULL, NULL, NULL); do { ret = expand_one_shrinker_info(memcg, map_size, defer_size, - old_map_size, old_defer_size); + old_map_size, old_defer_size, + new_nr_max); if (ret) { mem_cgroup_iter_break(NULL, memcg); goto out; @@ -352,9 +351,11 @@ void set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id) rcu_read_lock(); info = rcu_dereference(memcg->nodeinfo[nid]->shrinker_info); - /* Pairs with smp mb in shrink_slab() */ - smp_mb__before_atomic(); - set_bit(shrinker_id, info->map); + if (!WARN_ON_ONCE(shrinker_id >= info->map_nr_max)) { + /* Pairs with smp mb in shrink_slab() */ + smp_mb__before_atomic(); + set_bit(shrinker_id, info->map); + } rcu_read_unlock(); } } @@ -432,7 +433,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memcg) for_each_node(nid) { child_info = shrinker_info_protected(memcg, nid); parent_info = shrinker_info_protected(parent, nid); - for (i = 0; i < shrinker_nr_max; i++) { + for (i = 0; i < child_info->map_nr_max; i++) { nr = atomic_long_read(&child_info->nr_deferred[i]); atomic_long_add(nr, &parent_info->nr_deferred[i]); } @@ -899,7 +900,7 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid, if (unlikely(!info)) goto unlock; - for_each_set_bit(i, info->map, shrinker_nr_max) { + for_each_set_bit(i, info->map, info->map_nr_max) { struct shrink_control sc = { .gfp_mask = gfp_mask, .nid = nid, -- cgit v1.2.3 From 3c556d2425b04054e22045d4ef7d34f163b7a71a Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Wed, 15 Mar 2023 13:16:42 -0400 Subject: mm/thp: rename TRANSPARENT_HUGEPAGE_NEVER_DAX to _UNSUPPORTED TRANSPARENT_HUGEPAGE_NEVER_DAX has nothing to do with DAX. It's set when has_transparent_hugepage() returns false, checked in hugepage_vma_check() and will disable THP completely if false. Rename it to TRANSPARENT_HUGEPAGE_UNSUPPORTED to reflect its real purpose. [peterx@redhat.com: fix comment, per David] Link: https://lkml.kernel.org/r/ZBMzQW674oHQJV7F@x1n Link: https://lkml.kernel.org/r/20230315171642.1244625-1-peterx@redhat.com Signed-off-by: Peter Xu Acked-by: David Hildenbrand Cc: Aneesh Kumar K.V Cc: Yang Shi Signed-off-by: Andrew Morton --- include/linux/huge_mm.h | 2 +- mm/huge_memory.c | 8 ++------ 2 files changed, 3 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 70bd867eba94..9a3a3af2dd80 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -79,7 +79,7 @@ static inline vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, } enum transparent_hugepage_flag { - TRANSPARENT_HUGEPAGE_NEVER_DAX, + TRANSPARENT_HUGEPAGE_UNSUPPORTED, TRANSPARENT_HUGEPAGE_FLAG, TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, TRANSPARENT_HUGEPAGE_DEFRAG_DIRECT_FLAG, diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 0c1df321ad64..cbf095e7f059 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -88,7 +88,7 @@ bool hugepage_vma_check(struct vm_area_struct *vma, unsigned long vm_flags, /* * If the hardware/firmware marked hugepage support disabled. */ - if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_NEVER_DAX)) + if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED)) return false; /* khugepaged doesn't collapse DAX vma, but page fault is fine. */ @@ -460,11 +460,7 @@ static int __init hugepage_init(void) struct kobject *hugepage_kobj; if (!has_transparent_hugepage()) { - /* - * Hardware doesn't support hugepages, hence disable - * DAX PMD support. - */ - transparent_hugepage_flags = 1 << TRANSPARENT_HUGEPAGE_NEVER_DAX; + transparent_hugepage_flags = 1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED; return -EINVAL; } -- cgit v1.2.3 From 263e721e3ba1f3b42ad61aed3d504f3c8c9c0eb6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 7 Mar 2023 15:34:05 +0100 Subject: mm: make mapping_get_entry available outside of filemap.c mapping_get_entry is useful for page cache API users that need to know about xa_value internals. Rename it and make it available in pagemap.h. Link: https://lkml.kernel.org/r/20230307143410.28031-3-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Matthew Wilcox (Oracle) Cc: Andreas Gruenbacher Cc: Hugh Dickins Cc: Ryusuke Konishi Signed-off-by: Andrew Morton --- include/linux/pagemap.h | 1 + mm/filemap.c | 6 +++--- 2 files changed, 4 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 853184a46411..bcfd798ce0b9 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -507,6 +507,7 @@ pgoff_t page_cache_prev_miss(struct address_space *mapping, #define FGP_ENTRY 0x00000080 #define FGP_STABLE 0x00000100 +void *filemap_get_entry(struct address_space *mapping, pgoff_t index); struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, int fgp_flags, gfp_t gfp); struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, diff --git a/mm/filemap.c b/mm/filemap.c index 2723104cc06a..a674108a4d52 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1836,7 +1836,7 @@ EXPORT_SYMBOL(page_cache_prev_miss); */ /* - * mapping_get_entry - Get a page cache entry. + * filemap_get_entry - Get a page cache entry. * @mapping: the address_space to search * @index: The page cache index. * @@ -1847,7 +1847,7 @@ EXPORT_SYMBOL(page_cache_prev_miss); * * Return: The folio, swap or shadow entry, %NULL if nothing is found. */ -static void *mapping_get_entry(struct address_space *mapping, pgoff_t index) +void *filemap_get_entry(struct address_space *mapping, pgoff_t index) { XA_STATE(xas, &mapping->i_pages, index); struct folio *folio; @@ -1917,7 +1917,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, struct folio *folio; repeat: - folio = mapping_get_entry(mapping, index); + folio = filemap_get_entry(mapping, index); if (xa_is_value(folio)) { if (fgp_flags & FGP_ENTRY) return folio; -- cgit v1.2.3 From 48c9d11375fc66f1e59d0e9b27d121e015a50904 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 7 Mar 2023 15:34:09 +0100 Subject: mm: remove FGP_ENTRY FGP_ENTRY is unused now, so remove it. Link: https://lkml.kernel.org/r/20230307143410.28031-7-hch@lst.de Signed-off-by: Christoph Hellwig Cc: Andreas Gruenbacher Cc: Hugh Dickins Cc: Matthew Wilcox (Oracle) Cc: Ryusuke Konishi Signed-off-by: Andrew Morton --- include/linux/pagemap.h | 3 +-- mm/filemap.c | 7 +------ mm/folio-compat.c | 4 ++-- 3 files changed, 4 insertions(+), 10 deletions(-) (limited to 'include') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index bcfd798ce0b9..306a0f63cea8 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -504,8 +504,7 @@ pgoff_t page_cache_prev_miss(struct address_space *mapping, #define FGP_NOFS 0x00000010 #define FGP_NOWAIT 0x00000020 #define FGP_FOR_MMAP 0x00000040 -#define FGP_ENTRY 0x00000080 -#define FGP_STABLE 0x00000100 +#define FGP_STABLE 0x00000080 void *filemap_get_entry(struct address_space *mapping, pgoff_t index); struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, diff --git a/mm/filemap.c b/mm/filemap.c index a674108a4d52..ac161b50f5bc 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1891,8 +1891,6 @@ out: * * * %FGP_ACCESSED - The folio will be marked accessed. * * %FGP_LOCK - The folio is returned locked. - * * %FGP_ENTRY - If there is a shadow / swap / DAX entry, return it - * instead of allocating a new folio to replace it. * * %FGP_CREAT - If no page is present then a new page is allocated using * @gfp and added to the page cache and the VM's LRU list. * The page is returned locked and with an increased refcount. @@ -1918,11 +1916,8 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, repeat: folio = filemap_get_entry(mapping, index); - if (xa_is_value(folio)) { - if (fgp_flags & FGP_ENTRY) - return folio; + if (xa_is_value(folio)) folio = NULL; - } if (!folio) goto no_page; diff --git a/mm/folio-compat.c b/mm/folio-compat.c index cabcd1de9ecb..1754daa85d35 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -97,8 +97,8 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, struct folio *folio; folio = __filemap_get_folio(mapping, index, fgp_flags, gfp); - if (!folio || xa_is_value(folio)) - return &folio->page; + if (!folio) + return NULL; return folio_file_page(folio, index); } EXPORT_SYMBOL(pagecache_get_page); -- cgit v1.2.3 From 66dabbb65d673aef40dd17bf62c042be8f6d4a4b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 7 Mar 2023 15:34:10 +0100 Subject: mm: return an ERR_PTR from __filemap_get_folio Instead of returning NULL for all errors, distinguish between: - no entry found and not asked to allocated (-ENOENT) - failed to allocate memory (-ENOMEM) - would block (-EAGAIN) so that callers don't have to guess the error based on the passed in flags. Also pass through the error through the direct callers: filemap_get_folio, filemap_lock_folio filemap_grab_folio and filemap_get_incore_folio. [hch@lst.de: fix null-pointer deref] Link: https://lkml.kernel.org/r/20230310070023.GA13563@lst.de Link: https://lkml.kernel.org/r/20230310043137.GA1624890@u2004 Link: https://lkml.kernel.org/r/20230307143410.28031-8-hch@lst.de Signed-off-by: Christoph Hellwig Acked-by: Ryusuke Konishi [nilfs2] Cc: Andreas Gruenbacher Cc: Hugh Dickins Cc: Matthew Wilcox (Oracle) Cc: Naoya Horiguchi Signed-off-by: Andrew Morton --- fs/afs/dir.c | 10 +++++----- fs/afs/dir_edit.c | 2 +- fs/afs/write.c | 4 ++-- fs/ext4/inode.c | 2 +- fs/ext4/move_extent.c | 8 ++++---- fs/hugetlbfs/inode.c | 2 +- fs/iomap/buffered-io.c | 11 ++--------- fs/netfs/buffered_read.c | 4 ++-- fs/nfs/file.c | 4 ++-- fs/nilfs2/page.c | 6 +++--- include/linux/pagemap.h | 11 ++++++----- mm/filemap.c | 14 ++++++++------ mm/folio-compat.c | 2 +- mm/huge_memory.c | 2 +- mm/hugetlb.c | 6 ++++-- mm/memcontrol.c | 2 +- mm/mincore.c | 2 +- mm/shmem.c | 4 ++-- mm/swap_state.c | 17 ++++++++++------- mm/swapfile.c | 4 ++-- mm/truncate.c | 15 ++++++++------- 21 files changed, 67 insertions(+), 65 deletions(-) (limited to 'include') diff --git a/fs/afs/dir.c b/fs/afs/dir.c index 82690d1dd49a..f92b9e62d567 100644 --- a/fs/afs/dir.c +++ b/fs/afs/dir.c @@ -319,16 +319,16 @@ expand: struct folio *folio; folio = filemap_get_folio(mapping, i); - if (!folio) { + if (IS_ERR(folio)) { if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) afs_stat_v(dvnode, n_inval); - - ret = -ENOMEM; folio = __filemap_get_folio(mapping, i, FGP_LOCK | FGP_CREAT, mapping->gfp_mask); - if (!folio) + if (IS_ERR(folio)) { + ret = PTR_ERR(folio); goto error; + } folio_attach_private(folio, (void *)1); folio_unlock(folio); } @@ -524,7 +524,7 @@ static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx, */ folio = __filemap_get_folio(dir->i_mapping, ctx->pos / PAGE_SIZE, FGP_ACCESSED, 0); - if (!folio) { + if (IS_ERR(folio)) { ret = afs_bad(dvnode, afs_file_error_dir_missing_page); break; } diff --git a/fs/afs/dir_edit.c b/fs/afs/dir_edit.c index 0ab7752d1b75..f0eddccbdd95 100644 --- a/fs/afs/dir_edit.c +++ b/fs/afs/dir_edit.c @@ -115,7 +115,7 @@ static struct folio *afs_dir_get_folio(struct afs_vnode *vnode, pgoff_t index) folio = __filemap_get_folio(mapping, index, FGP_LOCK | FGP_ACCESSED | FGP_CREAT, mapping->gfp_mask); - if (!folio) + if (IS_ERR(folio)) clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags); else if (folio && !folio_test_private(folio)) folio_attach_private(folio, (void *)1); diff --git a/fs/afs/write.c b/fs/afs/write.c index 571f3b9a417e..c822d6006033 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -232,7 +232,7 @@ static void afs_kill_pages(struct address_space *mapping, _debug("kill %lx (to %lx)", index, last); folio = filemap_get_folio(mapping, index); - if (!folio) { + if (IS_ERR(folio)) { next = index + 1; continue; } @@ -270,7 +270,7 @@ static void afs_redirty_pages(struct writeback_control *wbc, _debug("redirty %llx @%llx", len, start); folio = filemap_get_folio(mapping, index); - if (!folio) { + if (IS_ERR(folio)) { next = index + 1; continue; } diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index bf0b7dea4900..d7973743417b 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5395,7 +5395,7 @@ static void ext4_wait_for_tail_page_commit(struct inode *inode) while (1) { struct folio *folio = filemap_lock_folio(inode->i_mapping, inode->i_size >> PAGE_SHIFT); - if (!folio) + if (IS_ERR(folio)) return; ret = __ext4_journalled_invalidate_folio(folio, offset, folio_size(folio) - offset); diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index 2de9829aed63..7bf6d069199c 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -141,18 +141,18 @@ mext_folio_double_lock(struct inode *inode1, struct inode *inode2, flags = memalloc_nofs_save(); folio[0] = __filemap_get_folio(mapping[0], index1, fgp_flags, mapping_gfp_mask(mapping[0])); - if (!folio[0]) { + if (IS_ERR(folio[0])) { memalloc_nofs_restore(flags); - return -ENOMEM; + return PTR_ERR(folio[0]); } folio[1] = __filemap_get_folio(mapping[1], index2, fgp_flags, mapping_gfp_mask(mapping[1])); memalloc_nofs_restore(flags); - if (!folio[1]) { + if (IS_ERR(folio[1])) { folio_unlock(folio[0]); folio_put(folio[0]); - return -ENOMEM; + return PTR_ERR(folio[1]); } /* * __filemap_get_folio() may not wait on folio's writeback if diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 9062da6da567..702d79639c0d 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -697,7 +697,7 @@ static void hugetlbfs_zero_partial_page(struct hstate *h, struct folio *folio; folio = filemap_lock_folio(mapping, idx); - if (!folio) + if (IS_ERR(folio)) return; start = start & ~huge_page_mask(h); diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 6f4c97a6d7e9..96bb56c203f4 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -468,19 +468,12 @@ EXPORT_SYMBOL_GPL(iomap_is_partially_uptodate); struct folio *iomap_get_folio(struct iomap_iter *iter, loff_t pos) { unsigned fgp = FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE | FGP_NOFS; - struct folio *folio; if (iter->flags & IOMAP_NOWAIT) fgp |= FGP_NOWAIT; - folio = __filemap_get_folio(iter->inode->i_mapping, pos >> PAGE_SHIFT, + return __filemap_get_folio(iter->inode->i_mapping, pos >> PAGE_SHIFT, fgp, mapping_gfp_mask(iter->inode->i_mapping)); - if (folio) - return folio; - - if (iter->flags & IOMAP_NOWAIT) - return ERR_PTR(-EAGAIN); - return ERR_PTR(-ENOMEM); } EXPORT_SYMBOL_GPL(iomap_get_folio); @@ -911,7 +904,7 @@ static int iomap_write_delalloc_scan(struct inode *inode, /* grab locked page */ folio = filemap_lock_folio(inode->i_mapping, start_byte >> PAGE_SHIFT); - if (!folio) { + if (IS_ERR(folio)) { start_byte = ALIGN_DOWN(start_byte, PAGE_SIZE) + PAGE_SIZE; continue; diff --git a/fs/netfs/buffered_read.c b/fs/netfs/buffered_read.c index 7679a68e8193..209726a9cfdb 100644 --- a/fs/netfs/buffered_read.c +++ b/fs/netfs/buffered_read.c @@ -350,8 +350,8 @@ int netfs_write_begin(struct netfs_inode *ctx, retry: folio = __filemap_get_folio(mapping, index, fgp_flags, mapping_gfp_mask(mapping)); - if (!folio) - return -ENOMEM; + if (IS_ERR(folio)) + return PTR_ERR(folio); if (ctx->ops->check_write_begin) { /* Allow the netfs (eg. ceph) to flush conflicts. */ diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 893625eacab9..1d03406e6c03 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -336,8 +336,8 @@ static int nfs_write_begin(struct file *file, struct address_space *mapping, start: folio = nfs_folio_grab_cache_write_begin(mapping, pos >> PAGE_SHIFT); - if (!folio) - return -ENOMEM; + if (IS_ERR(folio)) + return PTR_ERR(folio); *pagep = &folio->page; ret = nfs_flush_incompatible(file, folio); diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c index 41ccd43cd979..5cf30827f244 100644 --- a/fs/nilfs2/page.c +++ b/fs/nilfs2/page.c @@ -259,10 +259,10 @@ repeat: NILFS_PAGE_BUG(&folio->page, "inconsistent dirty state"); dfolio = filemap_grab_folio(dmap, folio->index); - if (unlikely(!dfolio)) { + if (unlikely(IS_ERR(dfolio))) { /* No empty page is added to the page cache */ - err = -ENOMEM; folio_unlock(folio); + err = PTR_ERR(dfolio); break; } if (unlikely(!folio_buffers(folio))) @@ -311,7 +311,7 @@ repeat: folio_lock(folio); dfolio = filemap_lock_folio(dmap, index); - if (dfolio) { + if (!IS_ERR(dfolio)) { /* overwrite existing folio in the destination cache */ WARN_ON(folio_test_dirty(dfolio)); nilfs_copy_page(&dfolio->page, &folio->page, 0); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 306a0f63cea8..fdcd595d2294 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -520,7 +520,8 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, * Looks up the page cache entry at @mapping & @index. If a folio is * present, it is returned with an increased refcount. * - * Otherwise, %NULL is returned. + * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for + * this index. Will not return a shadow, swap or DAX entry. */ static inline struct folio *filemap_get_folio(struct address_space *mapping, pgoff_t index) @@ -537,8 +538,8 @@ static inline struct folio *filemap_get_folio(struct address_space *mapping, * present, it is returned locked with an increased refcount. * * Context: May sleep. - * Return: A folio or %NULL if there is no folio in the cache for this - * index. Will not return a shadow, swap or DAX entry. + * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for + * this index. Will not return a shadow, swap or DAX entry. */ static inline struct folio *filemap_lock_folio(struct address_space *mapping, pgoff_t index) @@ -555,8 +556,8 @@ static inline struct folio *filemap_lock_folio(struct address_space *mapping, * a new folio is created. The folio is locked, marked as accessed, and * returned. * - * Return: A found or created folio. NULL if no folio is found and failed to - * create a folio. + * Return: A found or created folio. ERR_PTR(-ENOMEM) if no folio is found + * and failed to create a folio. */ static inline struct folio *filemap_grab_folio(struct address_space *mapping, pgoff_t index) diff --git a/mm/filemap.c b/mm/filemap.c index ac161b50f5bc..a34abfe8c654 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1907,7 +1907,7 @@ out: * * If there is a page cache page, it is returned with an increased refcount. * - * Return: The found folio or %NULL otherwise. + * Return: The found folio or an ERR_PTR() otherwise. */ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, int fgp_flags, gfp_t gfp) @@ -1925,7 +1925,7 @@ repeat: if (fgp_flags & FGP_NOWAIT) { if (!folio_trylock(folio)) { folio_put(folio); - return NULL; + return ERR_PTR(-EAGAIN); } } else { folio_lock(folio); @@ -1964,7 +1964,7 @@ no_page: folio = filemap_alloc_folio(gfp, 0); if (!folio) - return NULL; + return ERR_PTR(-ENOMEM); if (WARN_ON_ONCE(!(fgp_flags & (FGP_LOCK | FGP_FOR_MMAP)))) fgp_flags |= FGP_LOCK; @@ -1989,6 +1989,8 @@ no_page: folio_unlock(folio); } + if (!folio) + return ERR_PTR(-ENOENT); return folio; } EXPORT_SYMBOL(__filemap_get_folio); @@ -3258,7 +3260,7 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) * Do we have something in the page cache already? */ folio = filemap_get_folio(mapping, index); - if (likely(folio)) { + if (likely(!IS_ERR(folio))) { /* * We found the page, so try async readahead before waiting for * the lock. @@ -3287,7 +3289,7 @@ retry_find: folio = __filemap_get_folio(mapping, index, FGP_CREAT|FGP_FOR_MMAP, vmf->gfp_mask); - if (!folio) { + if (IS_ERR(folio)) { if (fpin) goto out_retry; filemap_invalidate_unlock_shared(mapping); @@ -3638,7 +3640,7 @@ static struct folio *do_read_cache_folio(struct address_space *mapping, filler = mapping->a_ops->read_folio; repeat: folio = filemap_get_folio(mapping, index); - if (!folio) { + if (IS_ERR(folio)) { folio = filemap_alloc_folio(gfp, 0); if (!folio) return ERR_PTR(-ENOMEM); diff --git a/mm/folio-compat.c b/mm/folio-compat.c index 1754daa85d35..2511c055a35f 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -97,7 +97,7 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, struct folio *folio; folio = __filemap_get_folio(mapping, index, fgp_flags, gfp); - if (!folio) + if (IS_ERR(folio)) return NULL; return folio_file_page(folio, index); } diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 70008dd7f215..2d860e70fe88 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3092,7 +3092,7 @@ static int split_huge_pages_in_file(const char *file_path, pgoff_t off_start, struct folio *folio = filemap_get_folio(mapping, index); nr_pages = 1; - if (!folio) + if (IS_ERR(folio)) continue; if (!folio_test_large(folio)) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 07abcb6eb203..712e32b38295 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5780,7 +5780,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, */ new_folio = false; folio = filemap_lock_folio(mapping, idx); - if (!folio) { + if (IS_ERR(folio)) { size = i_size_read(mapping->host) >> huge_page_shift(h); if (idx >= size) goto out; @@ -6071,6 +6071,8 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, vma_end_reservation(h, vma, haddr); pagecache_folio = filemap_lock_folio(mapping, idx); + if (IS_ERR(pagecache_folio)) + pagecache_folio = NULL; } ptl = huge_pte_lock(h, mm, ptep); @@ -6182,7 +6184,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, if (is_continue) { ret = -EFAULT; folio = filemap_lock_folio(mapping, idx); - if (!folio) + if (IS_ERR(folio)) goto out; folio_in_pagecache = true; } else if (!*pagep) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 13ec89c45389..0524add35cae 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5705,7 +5705,7 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma, /* shmem/tmpfs may report page out on swap: account for that too. */ index = linear_page_index(vma, addr); folio = filemap_get_incore_folio(vma->vm_file->f_mapping, index); - if (!folio) + if (IS_ERR(folio)) return NULL; return folio_file_page(folio, index); } diff --git a/mm/mincore.c b/mm/mincore.c index d359650b0f75..2d5be013a25a 100644 --- a/mm/mincore.c +++ b/mm/mincore.c @@ -61,7 +61,7 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t index) * tmpfs's .fault). So swapped out tmpfs mappings are tested here. */ folio = filemap_get_incore_folio(mapping, index); - if (folio) { + if (!IS_ERR(folio)) { present = folio_test_uptodate(folio); folio_put(folio); } diff --git a/mm/shmem.c b/mm/shmem.c index 93cb39852a16..fa6e38f2f55f 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -605,7 +605,7 @@ next: index = (inode->i_size & HPAGE_PMD_MASK) >> PAGE_SHIFT; folio = filemap_get_folio(inode->i_mapping, index); - if (!folio) + if (IS_ERR(folio)) goto drop; /* No huge page at the end of the file: nothing to split */ @@ -3214,7 +3214,7 @@ static const char *shmem_get_link(struct dentry *dentry, if (!dentry) { folio = filemap_get_folio(inode->i_mapping, 0); - if (!folio) + if (IS_ERR(folio)) return ERR_PTR(-ECHILD); if (PageHWPoison(folio_page(folio, 0)) || !folio_test_uptodate(folio)) { diff --git a/mm/swap_state.c b/mm/swap_state.c index 92234f4b51d2..b76a65ac28b3 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -336,7 +336,7 @@ struct folio *swap_cache_get_folio(swp_entry_t entry, struct folio *folio; folio = filemap_get_folio(swap_address_space(entry), swp_offset(entry)); - if (folio) { + if (!IS_ERR(folio)) { bool vma_ra = swap_use_vma_readahead(); bool readahead; @@ -366,6 +366,8 @@ struct folio *swap_cache_get_folio(swp_entry_t entry, if (!vma || !vma_ra) atomic_inc(&swapin_readahead_hits); } + } else { + folio = NULL; } return folio; @@ -388,23 +390,24 @@ struct folio *filemap_get_incore_folio(struct address_space *mapping, struct swap_info_struct *si; struct folio *folio = filemap_get_entry(mapping, index); + if (!folio) + return ERR_PTR(-ENOENT); if (!xa_is_value(folio)) - goto out; + return folio; if (!shmem_mapping(mapping)) - return NULL; + return ERR_PTR(-ENOENT); swp = radix_to_swp_entry(folio); /* There might be swapin error entries in shmem mapping. */ if (non_swap_entry(swp)) - return NULL; + return ERR_PTR(-ENOENT); /* Prevent swapoff from happening to us */ si = get_swap_device(swp); if (!si) - return NULL; + return ERR_PTR(-ENOENT); index = swp_offset(swp); folio = filemap_get_folio(swap_address_space(swp), index); put_swap_device(si); -out: return folio; } @@ -431,7 +434,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, folio = filemap_get_folio(swap_address_space(entry), swp_offset(entry)); put_swap_device(si); - if (folio) + if (!IS_ERR(folio)) return folio_file_page(folio, swp_offset(entry)); /* diff --git a/mm/swapfile.c b/mm/swapfile.c index c1b97436f811..00b3e46becad 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -136,7 +136,7 @@ static int __try_to_reclaim_swap(struct swap_info_struct *si, int ret = 0; folio = filemap_get_folio(swap_address_space(entry), offset); - if (!folio) + if (IS_ERR(folio)) return 0; /* * When this function is called from scan_swap_map_slots() and it's @@ -2095,7 +2095,7 @@ retry: entry = swp_entry(type, i); folio = filemap_get_folio(swap_address_space(entry), i); - if (!folio) + if (IS_ERR(folio)) continue; /* diff --git a/mm/truncate.c b/mm/truncate.c index 7b4ea4c4a46b..86de31ed4d32 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -375,7 +375,7 @@ void truncate_inode_pages_range(struct address_space *mapping, same_folio = (lstart >> PAGE_SHIFT) == (lend >> PAGE_SHIFT); folio = __filemap_get_folio(mapping, lstart >> PAGE_SHIFT, FGP_LOCK, 0); - if (folio) { + if (!IS_ERR(folio)) { same_folio = lend < folio_pos(folio) + folio_size(folio); if (!truncate_inode_partial_folio(folio, lstart, lend)) { start = folio->index + folio_nr_pages(folio); @@ -387,14 +387,15 @@ void truncate_inode_pages_range(struct address_space *mapping, folio = NULL; } - if (!same_folio) + if (!same_folio) { folio = __filemap_get_folio(mapping, lend >> PAGE_SHIFT, FGP_LOCK, 0); - if (folio) { - if (!truncate_inode_partial_folio(folio, lstart, lend)) - end = folio->index; - folio_unlock(folio); - folio_put(folio); + if (!IS_ERR(folio)) { + if (!truncate_inode_partial_folio(folio, lstart, lend)) + end = folio->index; + folio_unlock(folio); + folio_put(folio); + } } index = start; -- cgit v1.2.3 From 2bad466cc9d9b4c3b4b16eb9c03c919b59561316 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Thu, 9 Mar 2023 17:37:10 -0500 Subject: mm/uffd: UFFD_FEATURE_WP_UNPOPULATED Patch series "mm/uffd: Add feature bit UFFD_FEATURE_WP_UNPOPULATED", v4. The new feature bit makes anonymous memory acts the same as file memory on userfaultfd-wp in that it'll also wr-protect none ptes. It can be useful in two cases: (1) Uffd-wp app that needs to wr-protect none ptes like QEMU snapshot, so pre-fault can be replaced by enabling this flag and speed up protections (2) It helps to implement async uffd-wp mode that Muhammad is working on [1] It's debatable whether this is the most ideal solution because with the new feature bit set, wr-protect none pte needs to pre-populate the pgtables to the last level (PAGE_SIZE). But it seems fine so far to service either purpose above, so we can leave optimizations for later. The series brings pte markers to anonymous memory too. There's some change in the common mm code path in the 1st patch, great to have some eye looking at it, but hopefully they're still relatively straightforward. This patch (of 2): This is a new feature that controls how uffd-wp handles none ptes. When it's set, the kernel will handle anonymous memory the same way as file memory, by allowing the user to wr-protect unpopulated ptes. File memories handles none ptes consistently by allowing wr-protecting of none ptes because of the unawareness of page cache being exist or not. For anonymous it was not as persistent because we used to assume that we don't need protections on none ptes or known zero pages. One use case of such a feature bit was VM live snapshot, where if without wr-protecting empty ptes the snapshot can contain random rubbish in the holes of the anonymous memory, which can cause misbehave of the guest when the guest OS assumes the pages should be all zeros. QEMU worked it around by pre-populate the section with reads to fill in zero page entries before starting the whole snapshot process [1]. Recently there's another need raised on using userfaultfd wr-protect for detecting dirty pages (to replace soft-dirty in some cases) [2]. In that case if without being able to wr-protect none ptes by default, the dirty info can get lost, since we cannot treat every none pte to be dirty (the current design is identify a page dirty based on uffd-wp bit being cleared). In general, we want to be able to wr-protect empty ptes too even for anonymous. This patch implements UFFD_FEATURE_WP_UNPOPULATED so that it'll make uffd-wp handling on none ptes being consistent no matter what the memory type is underneath. It doesn't have any impact on file memories so far because we already have pte markers taking care of that. So it only affects anonymous. The feature bit is by default off, so the old behavior will be maintained. Sometimes it may be wanted because the wr-protect of none ptes will contain overheads not only during UFFDIO_WRITEPROTECT (by applying pte markers to anonymous), but also on creating the pgtables to store the pte markers. So there's potentially less chance of using thp on the first fault for a none pmd or larger than a pmd. The major implementation part is teaching the whole kernel to understand pte markers even for anonymously mapped ranges, meanwhile allowing the UFFDIO_WRITEPROTECT ioctl to apply pte markers for anonymous too when the new feature bit is set. Note that even if the patch subject starts with mm/uffd, there're a few small refactors to major mm path of handling anonymous page faults. But they should be straightforward. With WP_UNPOPUATED, application like QEMU can avoid pre-read faults all the memory before wr-protect during taking a live snapshot. Quotting from Muhammad's test result here [3] based on a simple program [4]: (1) With huge page disabled echo madvise > /sys/kernel/mm/transparent_hugepage/enabled ./uffd_wp_perf Test DEFAULT: 4 Test PRE-READ: 1111453 (pre-fault 1101011) Test MADVISE: 278276 (pre-fault 266378) Test WP-UNPOPULATE: 11712 (2) With Huge page enabled echo always > /sys/kernel/mm/transparent_hugepage/enabled ./uffd_wp_perf Test DEFAULT: 4 Test PRE-READ: 22521 (pre-fault 22348) Test MADVISE: 4909 (pre-fault 4743) Test WP-UNPOPULATE: 14448 There'll be a great perf boost for no-thp case, while for thp enabled with extreme case of all-thp-zero WP_UNPOPULATED can be slower than MADVISE, but that's low possibility in reality, also the overhead was not reduced but postponed until a follow up write on any huge zero thp, so potentially it is faster by making the follow up writes slower. [1] https://lore.kernel.org/all/20210401092226.102804-4-andrey.gruzdev@virtuozzo.com/ [2] https://lore.kernel.org/all/Y+v2HJ8+3i%2FKzDBu@x1n/ [3] https://lore.kernel.org/all/d0eb0a13-16dc-1ac1-653a-78b7273781e3@collabora.com/ [4] https://github.com/xzpeter/clibs/blob/master/uffd-test/uffd-wp-perf.c [peterx@redhat.com: comment changes, oneliner fix to khugepaged] Link: https://lkml.kernel.org/r/ZB2/8jPhD3fpx5U8@x1n Link: https://lkml.kernel.org/r/20230309223711.823547-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20230309223711.823547-2-peterx@redhat.com Signed-off-by: Peter Xu Acked-by: David Hildenbrand Cc: Andrea Arcangeli Cc: Axel Rasmussen Cc: Mike Rapoport Cc: Muhammad Usama Anjum Cc: Nadav Amit Cc: Paul Gofman Signed-off-by: Andrew Morton --- Documentation/admin-guide/mm/userfaultfd.rst | 17 +++++++++ fs/userfaultfd.c | 16 ++++++++ include/linux/mm_inline.h | 6 +++ include/linux/userfaultfd_k.h | 23 ++++++++++++ include/uapi/linux/userfaultfd.h | 10 ++++- mm/khugepaged.c | 2 +- mm/memory.c | 56 +++++++++++++++++++++------- mm/mprotect.c | 51 ++++++++++++++++++++----- 8 files changed, 155 insertions(+), 26 deletions(-) (limited to 'include') diff --git a/Documentation/admin-guide/mm/userfaultfd.rst b/Documentation/admin-guide/mm/userfaultfd.rst index 7dc823b56ca4..bd2226299583 100644 --- a/Documentation/admin-guide/mm/userfaultfd.rst +++ b/Documentation/admin-guide/mm/userfaultfd.rst @@ -219,6 +219,23 @@ former will have ``UFFD_PAGEFAULT_FLAG_WP`` set, the latter you still need to supply a page when ``UFFDIO_REGISTER_MODE_MISSING`` was used. +Userfaultfd write-protect mode currently behave differently on none ptes +(when e.g. page is missing) over different types of memories. + +For anonymous memory, ``ioctl(UFFDIO_WRITEPROTECT)`` will ignore none ptes +(e.g. when pages are missing and not populated). For file-backed memories +like shmem and hugetlbfs, none ptes will be write protected just like a +present pte. In other words, there will be a userfaultfd write fault +message generated when writing to a missing page on file typed memories, +as long as the page range was write-protected before. Such a message will +not be generated on anonymous memories by default. + +If the application wants to be able to write protect none ptes on anonymous +memory, one can pre-populate the memory with e.g. MADV_POPULATE_READ. On +newer kernels, one can also detect the feature UFFD_FEATURE_WP_UNPOPULATED +and set the feature bit in advance to make sure none ptes will also be +write protected even upon anonymous memory. + QEMU/KVM ======== diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 44d1ee429eb0..881e9c82b9d1 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -108,6 +108,21 @@ static bool userfaultfd_is_initialized(struct userfaultfd_ctx *ctx) return ctx->features & UFFD_FEATURE_INITIALIZED; } +/* + * Whether WP_UNPOPULATED is enabled on the uffd context. It is only + * meaningful when userfaultfd_wp()==true on the vma and when it's + * anonymous. + */ +bool userfaultfd_wp_unpopulated(struct vm_area_struct *vma) +{ + struct userfaultfd_ctx *ctx = vma->vm_userfaultfd_ctx.ctx; + + if (!ctx) + return false; + + return ctx->features & UFFD_FEATURE_WP_UNPOPULATED; +} + static void userfaultfd_set_vm_flags(struct vm_area_struct *vma, vm_flags_t flags) { @@ -1971,6 +1986,7 @@ static int userfaultfd_api(struct userfaultfd_ctx *ctx, #endif #ifndef CONFIG_PTE_MARKER_UFFD_WP uffdio_api.features &= ~UFFD_FEATURE_WP_HUGETLBFS_SHMEM; + uffdio_api.features &= ~UFFD_FEATURE_WP_UNPOPULATED; #endif uffdio_api.ioctls = UFFD_API_IOCTLS; ret = -EFAULT; diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h index de1e622dd366..0e1d239a882c 100644 --- a/include/linux/mm_inline.h +++ b/include/linux/mm_inline.h @@ -557,6 +557,12 @@ pte_install_uffd_wp_if_needed(struct vm_area_struct *vma, unsigned long addr, /* The current status of the pte should be "cleared" before calling */ WARN_ON_ONCE(!pte_none(*pte)); + /* + * NOTE: userfaultfd_wp_unpopulated() doesn't need this whole + * thing, because when zapping either it means it's dropping the + * page, or in TTU where the present pte will be quickly replaced + * with a swap pte. There's no way of leaking the bit. + */ if (vma_is_anonymous(vma) || !userfaultfd_wp(vma)) return; diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 3767f18114ef..0cf8880219da 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -179,6 +179,7 @@ extern int userfaultfd_unmap_prep(struct mm_struct *mm, unsigned long start, unsigned long end, struct list_head *uf); extern void userfaultfd_unmap_complete(struct mm_struct *mm, struct list_head *uf); +extern bool userfaultfd_wp_unpopulated(struct vm_area_struct *vma); #else /* CONFIG_USERFAULTFD */ @@ -274,8 +275,30 @@ static inline bool uffd_disable_fault_around(struct vm_area_struct *vma) return false; } +static inline bool userfaultfd_wp_unpopulated(struct vm_area_struct *vma) +{ + return false; +} + #endif /* CONFIG_USERFAULTFD */ +static inline bool userfaultfd_wp_use_markers(struct vm_area_struct *vma) +{ + /* Only wr-protect mode uses pte markers */ + if (!userfaultfd_wp(vma)) + return false; + + /* File-based uffd-wp always need markers */ + if (!vma_is_anonymous(vma)) + return true; + + /* + * Anonymous uffd-wp only needs the markers if WP_UNPOPULATED + * enabled (to apply markers on zero pages). + */ + return userfaultfd_wp_unpopulated(vma); +} + static inline bool pte_marker_entry_uffd_wp(swp_entry_t entry) { #ifdef CONFIG_PTE_MARKER_UFFD_WP diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h index 005e5e306266..90c958952bfc 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -38,7 +38,8 @@ UFFD_FEATURE_MINOR_HUGETLBFS | \ UFFD_FEATURE_MINOR_SHMEM | \ UFFD_FEATURE_EXACT_ADDRESS | \ - UFFD_FEATURE_WP_HUGETLBFS_SHMEM) + UFFD_FEATURE_WP_HUGETLBFS_SHMEM | \ + UFFD_FEATURE_WP_UNPOPULATED) #define UFFD_API_IOCTLS \ ((__u64)1 << _UFFDIO_REGISTER | \ (__u64)1 << _UFFDIO_UNREGISTER | \ @@ -203,6 +204,12 @@ struct uffdio_api { * * UFFD_FEATURE_WP_HUGETLBFS_SHMEM indicates that userfaultfd * write-protection mode is supported on both shmem and hugetlbfs. + * + * UFFD_FEATURE_WP_UNPOPULATED indicates that userfaultfd + * write-protection mode will always apply to unpopulated pages + * (i.e. empty ptes). This will be the default behavior for shmem + * & hugetlbfs, so this flag only affects anonymous memory behavior + * when userfault write-protection mode is registered. */ #define UFFD_FEATURE_PAGEFAULT_FLAG_WP (1<<0) #define UFFD_FEATURE_EVENT_FORK (1<<1) @@ -217,6 +224,7 @@ struct uffdio_api { #define UFFD_FEATURE_MINOR_SHMEM (1<<10) #define UFFD_FEATURE_EXACT_ADDRESS (1<<11) #define UFFD_FEATURE_WP_HUGETLBFS_SHMEM (1<<12) +#define UFFD_FEATURE_WP_UNPOPULATED (1<<13) __u64 features; __u64 ioctls; diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 074ea534f786..c7317678cb10 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1177,7 +1177,7 @@ static int hpage_collapse_scan_pmd(struct mm_struct *mm, * enabled swap entries. Please see * comment below for pte_uffd_wp(). */ - if (pte_swp_uffd_wp(pteval)) { + if (pte_swp_uffd_wp_any(pteval)) { result = SCAN_PTE_UFFD_WP; goto out_unmap; } diff --git a/mm/memory.c b/mm/memory.c index 6285cad1f4fb..a890b2951b53 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -104,6 +104,20 @@ EXPORT_SYMBOL(mem_map); #endif static vm_fault_t do_fault(struct vm_fault *vmf); +static vm_fault_t do_anonymous_page(struct vm_fault *vmf); +static bool vmf_pte_changed(struct vm_fault *vmf); + +/* + * Return true if the original pte was a uffd-wp pte marker (so the pte was + * wr-protected). + */ +static bool vmf_orig_pte_uffd_wp(struct vm_fault *vmf) +{ + if (!(vmf->flags & FAULT_FLAG_ORIG_PTE_VALID)) + return false; + + return pte_marker_uffd_wp(vmf->orig_pte); +} /* * A number of key systems in x86 including ioremap() rely on the assumption @@ -1346,6 +1360,10 @@ zap_install_uffd_wp_if_needed(struct vm_area_struct *vma, unsigned long addr, pte_t *pte, struct zap_details *details, pte_t pteval) { + /* Zap on anonymous always means dropping everything */ + if (vma_is_anonymous(vma)) + return; + if (zap_drop_file_uffd_wp(details)) return; @@ -1452,8 +1470,12 @@ again: continue; rss[mm_counter(page)]--; } else if (pte_marker_entry_uffd_wp(entry)) { - /* Only drop the uffd-wp marker if explicitly requested */ - if (!zap_drop_file_uffd_wp(details)) + /* + * For anon: always drop the marker; for file: only + * drop the marker if explicitly requested. + */ + if (!vma_is_anonymous(vma) && + !zap_drop_file_uffd_wp(details)) continue; } else if (is_hwpoison_entry(entry) || is_swapin_error_entry(entry)) { @@ -3620,6 +3642,14 @@ static vm_fault_t pte_marker_clear(struct vm_fault *vmf) return 0; } +static vm_fault_t do_pte_missing(struct vm_fault *vmf) +{ + if (vma_is_anonymous(vmf->vma)) + return do_anonymous_page(vmf); + else + return do_fault(vmf); +} + /* * This is actually a page-missing access, but with uffd-wp special pte * installed. It means this pte was wr-protected before being unmapped. @@ -3630,11 +3660,10 @@ static vm_fault_t pte_marker_handle_uffd_wp(struct vm_fault *vmf) * Just in case there're leftover special ptes even after the region * got unregistered - we can simply clear them. */ - if (unlikely(!userfaultfd_wp(vmf->vma) || vma_is_anonymous(vmf->vma))) + if (unlikely(!userfaultfd_wp(vmf->vma))) return pte_marker_clear(vmf); - /* do_fault() can handle pte markers too like none pte */ - return do_fault(vmf); + return do_pte_missing(vmf); } static vm_fault_t handle_pte_marker(struct vm_fault *vmf) @@ -3999,6 +4028,7 @@ out_release: */ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) { + bool uffd_wp = vmf_orig_pte_uffd_wp(vmf); struct vm_area_struct *vma = vmf->vma; struct folio *folio; vm_fault_t ret = 0; @@ -4032,7 +4062,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) vma->vm_page_prot)); vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); - if (!pte_none(*vmf->pte)) { + if (vmf_pte_changed(vmf)) { update_mmu_tlb(vma, vmf->address, vmf->pte); goto unlock; } @@ -4072,7 +4102,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); - if (!pte_none(*vmf->pte)) { + if (vmf_pte_changed(vmf)) { update_mmu_tlb(vma, vmf->address, vmf->pte); goto release; } @@ -4092,6 +4122,8 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) folio_add_new_anon_rmap(folio, vma, vmf->address); folio_add_lru_vma(folio, vma); setpte: + if (uffd_wp) + entry = pte_mkuffd_wp(entry); set_pte_at(vma->vm_mm, vmf->address, vmf->pte, entry); /* No need to invalidate - it was non-present before */ @@ -4259,7 +4291,7 @@ vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page) void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr) { struct vm_area_struct *vma = vmf->vma; - bool uffd_wp = pte_marker_uffd_wp(vmf->orig_pte); + bool uffd_wp = vmf_orig_pte_uffd_wp(vmf); bool write = vmf->flags & FAULT_FLAG_WRITE; bool prefault = vmf->address != addr; pte_t entry; @@ -4903,12 +4935,8 @@ static vm_fault_t handle_pte_fault(struct vm_fault *vmf) } } - if (!vmf->pte) { - if (vma_is_anonymous(vmf->vma)) - return do_anonymous_page(vmf); - else - return do_fault(vmf); - } + if (!vmf->pte) + return do_pte_missing(vmf); if (!pte_present(vmf->orig_pte)) return do_swap_page(vmf); diff --git a/mm/mprotect.c b/mm/mprotect.c index 13e84d8c0797..b9da9a5f87fe 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -276,7 +276,15 @@ static long change_pte_range(struct mmu_gather *tlb, } else { /* It must be an none page, or what else?.. */ WARN_ON_ONCE(!pte_none(oldpte)); - if (unlikely(uffd_wp && !vma_is_anonymous(vma))) { + + /* + * Nobody plays with any none ptes besides + * userfaultfd when applying the protections. + */ + if (likely(!uffd_wp)) + continue; + + if (userfaultfd_wp_use_markers(vma)) { /* * For file-backed mem, we need to be able to * wr-protect a none pte, because even if the @@ -320,23 +328,46 @@ static inline int pmd_none_or_clear_bad_unless_trans_huge(pmd_t *pmd) return 0; } -/* Return true if we're uffd wr-protecting file-backed memory, or false */ +/* + * Return true if we want to split THPs into PTE mappings in change + * protection procedure, false otherwise. + */ static inline bool -uffd_wp_protect_file(struct vm_area_struct *vma, unsigned long cp_flags) +pgtable_split_needed(struct vm_area_struct *vma, unsigned long cp_flags) { + /* + * pte markers only resides in pte level, if we need pte markers, + * we need to split. We cannot wr-protect shmem thp because file + * thp is handled differently when split by erasing the pmd so far. + */ return (cp_flags & MM_CP_UFFD_WP) && !vma_is_anonymous(vma); } /* - * If wr-protecting the range for file-backed, populate pgtable for the case - * when pgtable is empty but page cache exists. When {pte|pmd|...}_alloc() - * failed we treat it the same way as pgtable allocation failures during - * page faults by kicking OOM and returning error. + * Return true if we want to populate pgtables in change protection + * procedure, false otherwise + */ +static inline bool +pgtable_populate_needed(struct vm_area_struct *vma, unsigned long cp_flags) +{ + /* If not within ioctl(UFFDIO_WRITEPROTECT), then don't bother */ + if (!(cp_flags & MM_CP_UFFD_WP)) + return false; + + /* Populate if the userfaultfd mode requires pte markers */ + return userfaultfd_wp_use_markers(vma); +} + +/* + * Populate the pgtable underneath for whatever reason if requested. + * When {pte|pmd|...}_alloc() failed we treat it the same way as pgtable + * allocation failures during page faults by kicking OOM and returning + * error. */ #define change_pmd_prepare(vma, pmd, cp_flags) \ ({ \ long err = 0; \ - if (unlikely(uffd_wp_protect_file(vma, cp_flags))) { \ + if (unlikely(pgtable_populate_needed(vma, cp_flags))) { \ if (pte_alloc(vma->vm_mm, pmd)) \ err = -ENOMEM; \ } \ @@ -351,7 +382,7 @@ uffd_wp_protect_file(struct vm_area_struct *vma, unsigned long cp_flags) #define change_prepare(vma, high, low, addr, cp_flags) \ ({ \ long err = 0; \ - if (unlikely(uffd_wp_protect_file(vma, cp_flags))) { \ + if (unlikely(pgtable_populate_needed(vma, cp_flags))) { \ low##_t *p = low##_alloc(vma->vm_mm, high, addr); \ if (p == NULL) \ err = -ENOMEM; \ @@ -404,7 +435,7 @@ static inline long change_pmd_range(struct mmu_gather *tlb, if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) { if ((next - addr != HPAGE_PMD_SIZE) || - uffd_wp_protect_file(vma, cp_flags)) { + pgtable_split_needed(vma, cp_flags)) { __split_huge_pmd(vma, pmd, addr, false, NULL); /* * For file-backed, the pmd could have been -- cgit v1.2.3 From 23baf831a32c04f9a968812511540b1b3e648bf5 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Wed, 15 Mar 2023 14:31:33 +0300 Subject: mm, treewide: redefine MAX_ORDER sanely MAX_ORDER currently defined as number of orders page allocator supports: user can ask buddy allocator for page order between 0 and MAX_ORDER-1. This definition is counter-intuitive and lead to number of bugs all over the kernel. Change the definition of MAX_ORDER to be inclusive: the range of orders user can ask from buddy allocator is 0..MAX_ORDER now. [kirill@shutemov.name: fix min() warning] Link: https://lkml.kernel.org/r/20230315153800.32wib3n5rickolvh@box [akpm@linux-foundation.org: fix another min_t warning] [kirill@shutemov.name: fixups per Zi Yan] Link: https://lkml.kernel.org/r/20230316232144.b7ic4cif4kjiabws@box.shutemov.name [akpm@linux-foundation.org: fix underlining in docs] Link: https://lore.kernel.org/oe-kbuild-all/202303191025.VRCTk6mP-lkp@intel.com/ Link: https://lkml.kernel.org/r/20230315113133.11326-11-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Reviewed-by: Michael Ellerman [powerpc] Cc: "Kirill A. Shutemov" Cc: Zi Yan Signed-off-by: Andrew Morton --- Documentation/admin-guide/kdump/vmcoreinfo.rst | 6 ++-- Documentation/admin-guide/kernel-parameters.txt | 2 +- arch/arc/Kconfig | 4 +-- arch/arm/Kconfig | 9 ++---- arch/arm/configs/imx_v6_v7_defconfig | 2 +- arch/arm/configs/milbeaut_m10v_defconfig | 2 +- arch/arm/configs/oxnas_v6_defconfig | 2 +- arch/arm/configs/pxa_defconfig | 2 +- arch/arm/configs/sama7_defconfig | 2 +- arch/arm/configs/sp7021_defconfig | 2 +- arch/arm64/Kconfig | 27 ++++++++---------- arch/arm64/include/asm/sparsemem.h | 2 +- arch/arm64/kvm/hyp/include/nvhe/gfp.h | 2 +- arch/arm64/kvm/hyp/nvhe/page_alloc.c | 10 +++---- arch/csky/Kconfig | 2 +- arch/ia64/Kconfig | 8 +++--- arch/ia64/include/asm/sparsemem.h | 4 +-- arch/ia64/mm/hugetlbpage.c | 2 +- arch/loongarch/Kconfig | 15 ++++------ arch/m68k/Kconfig.cpu | 5 +--- arch/mips/Kconfig | 19 ++++++------- arch/nios2/Kconfig | 7 ++--- arch/powerpc/Kconfig | 27 ++++++++---------- arch/powerpc/configs/85xx/ge_imp3a_defconfig | 2 +- arch/powerpc/configs/fsl-emb-nonhw.config | 2 +- arch/powerpc/mm/book3s64/iommu_api.c | 2 +- arch/powerpc/mm/hugetlbpage.c | 2 +- arch/powerpc/platforms/powernv/pci-ioda.c | 2 +- arch/sh/configs/ecovec24_defconfig | 2 +- arch/sh/mm/Kconfig | 17 +++++------ arch/sparc/Kconfig | 5 +--- arch/sparc/kernel/pci_sun4v.c | 2 +- arch/sparc/kernel/traps_64.c | 2 +- arch/sparc/mm/tsb.c | 4 +-- arch/um/kernel/um_arch.c | 4 +-- arch/xtensa/Kconfig | 5 +--- drivers/base/regmap/regmap-debugfs.c | 8 +++--- drivers/block/floppy.c | 2 +- drivers/crypto/ccp/sev-dev.c | 2 +- drivers/crypto/hisilicon/sgl.c | 6 ++-- drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 +- drivers/gpu/drm/i915/gem/selftests/huge_pages.c | 2 +- drivers/gpu/drm/ttm/ttm_pool.c | 22 +++++++------- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 2 +- drivers/iommu/dma-iommu.c | 2 +- drivers/irqchip/irq-gic-v3-its.c | 4 +-- drivers/md/dm-bufio.c | 2 +- drivers/misc/genwqe/card_dev.c | 2 +- drivers/misc/genwqe/card_utils.c | 4 +-- drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 2 +- drivers/net/ethernet/ibm/ibmvnic.h | 2 +- drivers/video/fbdev/hyperv_fb.c | 4 +-- drivers/video/fbdev/vermilion/vermilion.c | 2 +- drivers/virtio/virtio_balloon.c | 2 +- drivers/virtio/virtio_mem.c | 12 ++++---- fs/ramfs/file-nommu.c | 2 +- include/drm/ttm/ttm_pool.h | 2 +- include/linux/hugetlb.h | 2 +- include/linux/mmzone.h | 10 +++---- include/linux/pageblock-flags.h | 4 +-- include/linux/slab.h | 6 ++-- kernel/crash_core.c | 2 +- kernel/dma/pool.c | 6 ++-- kernel/events/ring_buffer.c | 6 ++-- mm/Kconfig | 10 +++---- mm/compaction.c | 8 +++--- mm/debug_vm_pgtable.c | 4 +-- mm/huge_memory.c | 2 +- mm/hugetlb.c | 4 +-- mm/kmsan/init.c | 6 ++-- mm/memblock.c | 2 +- mm/memory_hotplug.c | 4 +-- mm/page_alloc.c | 38 ++++++++++++------------- mm/page_isolation.c | 12 ++++---- mm/page_owner.c | 6 ++-- mm/page_reporting.c | 6 ++-- mm/shuffle.h | 2 +- mm/slab.c | 2 +- mm/slub.c | 6 ++-- mm/vmscan.c | 2 +- mm/vmstat.c | 14 ++++----- net/smc/smc_ib.c | 2 +- security/integrity/ima/ima_crypto.c | 2 +- tools/testing/memblock/linux/mmzone.h | 6 ++-- 84 files changed, 223 insertions(+), 253 deletions(-) (limited to 'include') diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst index 86fd88492870..c18d94fa6470 100644 --- a/Documentation/admin-guide/kdump/vmcoreinfo.rst +++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst @@ -172,7 +172,7 @@ variables. Offset of the free_list's member. This value is used to compute the number of free pages. -Each zone has a free_area structure array called free_area[MAX_ORDER]. +Each zone has a free_area structure array called free_area[MAX_ORDER + 1]. The free_list represents a linked list of free page blocks. (list_head, next|prev) @@ -189,8 +189,8 @@ Offsets of the vmap_area's members. They carry vmalloc-specific information. Makedumpfile gets the start address of the vmalloc region from this. -(zone.free_area, MAX_ORDER) ---------------------------- +(zone.free_area, MAX_ORDER + 1) +------------------------------- Free areas descriptor. User-space tools use this value to iterate the free_area ranges. MAX_ORDER is used by the zone buddy allocator. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6221a1d057dd..50da4f26fad5 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3969,7 +3969,7 @@ [KNL] Minimal page reporting order Format: Adjust the minimal page reporting order. The page - reporting is disabled when it exceeds (MAX_ORDER-1). + reporting is disabled when it exceeds MAX_ORDER. panic= [KNL] Kernel behaviour on panic: delay timeout > 0: seconds before rebooting diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index d9a13ccf89a3..ab6d701365bb 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -556,7 +556,7 @@ endmenu # "ARC Architecture Configuration" config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "12" if ARC_HUGEPAGE_16M - default "11" + default "11" if ARC_HUGEPAGE_16M + default "10" source "kernel/power/Kconfig" diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index e24a9820e12f..929e646e84b9 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1355,9 +1355,9 @@ config ARM_MODULE_PLTS config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "12" if SOC_AM33XX - default "9" if SA1111 - default "11" + default "11" if SOC_AM33XX + default "8" if SA1111 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -1366,9 +1366,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - config ALIGNMENT_TRAP def_bool CPU_CP15_MMU select HAVE_PROC_CPU if PROC_FS diff --git a/arch/arm/configs/imx_v6_v7_defconfig b/arch/arm/configs/imx_v6_v7_defconfig index 6dc6fed12af8..345a67e67dbd 100644 --- a/arch/arm/configs/imx_v6_v7_defconfig +++ b/arch/arm/configs/imx_v6_v7_defconfig @@ -31,7 +31,7 @@ CONFIG_SOC_VF610=y CONFIG_SMP=y CONFIG_ARM_PSCI=y CONFIG_HIGHMEM=y -CONFIG_ARCH_FORCE_MAX_ORDER=14 +CONFIG_ARCH_FORCE_MAX_ORDER=13 CONFIG_CMDLINE="noinitrd console=ttymxc0,115200" CONFIG_KEXEC=y CONFIG_CPU_FREQ=y diff --git a/arch/arm/configs/milbeaut_m10v_defconfig b/arch/arm/configs/milbeaut_m10v_defconfig index bd29e5012cb0..385ad0f391a8 100644 --- a/arch/arm/configs/milbeaut_m10v_defconfig +++ b/arch/arm/configs/milbeaut_m10v_defconfig @@ -26,7 +26,7 @@ CONFIG_THUMB2_KERNEL=y # CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11 is not set # CONFIG_ARM_PATCH_IDIV is not set CONFIG_HIGHMEM=y -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_SECCOMP=y CONFIG_KEXEC=y CONFIG_EFI=y diff --git a/arch/arm/configs/oxnas_v6_defconfig b/arch/arm/configs/oxnas_v6_defconfig index 70a67b3fc91b..90779812c6dd 100644 --- a/arch/arm/configs/oxnas_v6_defconfig +++ b/arch/arm/configs/oxnas_v6_defconfig @@ -12,7 +12,7 @@ CONFIG_ARCH_OXNAS=y CONFIG_MACH_OX820=y CONFIG_SMP=y CONFIG_NR_CPUS=16 -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_SECCOMP=y CONFIG_ARM_APPENDED_DTB=y CONFIG_ARM_ATAG_DTB_COMPAT=y diff --git a/arch/arm/configs/pxa_defconfig b/arch/arm/configs/pxa_defconfig index e656d3af2266..b46e39369dbb 100644 --- a/arch/arm/configs/pxa_defconfig +++ b/arch/arm/configs/pxa_defconfig @@ -20,7 +20,7 @@ CONFIG_PXA_SHARPSL=y CONFIG_MACH_AKITA=y CONFIG_MACH_BORZOI=y CONFIG_AEABI=y -CONFIG_ARCH_FORCE_MAX_ORDER=9 +CONFIG_ARCH_FORCE_MAX_ORDER=8 CONFIG_CMDLINE="root=/dev/ram0 ro" CONFIG_KEXEC=y CONFIG_CPU_FREQ=y diff --git a/arch/arm/configs/sama7_defconfig b/arch/arm/configs/sama7_defconfig index 0d964c613d71..954112041403 100644 --- a/arch/arm/configs/sama7_defconfig +++ b/arch/arm/configs/sama7_defconfig @@ -19,7 +19,7 @@ CONFIG_ATMEL_CLOCKSOURCE_TCB=y # CONFIG_CACHE_L2X0 is not set # CONFIG_ARM_PATCH_IDIV is not set # CONFIG_CPU_SW_DOMAIN_PAN is not set -CONFIG_ARCH_FORCE_MAX_ORDER=15 +CONFIG_ARCH_FORCE_MAX_ORDER=14 CONFIG_UACCESS_WITH_MEMCPY=y # CONFIG_ATAGS is not set CONFIG_CMDLINE="console=ttyS0,115200 earlyprintk ignore_loglevel" diff --git a/arch/arm/configs/sp7021_defconfig b/arch/arm/configs/sp7021_defconfig index 5bca2eb59b86..c6448ac860b6 100644 --- a/arch/arm/configs/sp7021_defconfig +++ b/arch/arm/configs/sp7021_defconfig @@ -17,7 +17,7 @@ CONFIG_ARCH_SUNPLUS=y # CONFIG_VDSO is not set CONFIG_SMP=y CONFIG_THUMB2_KERNEL=y -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_VFP=y CONFIG_NEON=y CONFIG_MODULES=y diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1023e896d46b..cb5c6aa3254e 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1476,22 +1476,22 @@ config XEN # include/linux/mmzone.h requires the following to be true: # -# MAX_ORDER - 1 + PAGE_SHIFT <= SECTION_SIZE_BITS +# MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS # -# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS + 1 - PAGE_SHIFT: +# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT: # # | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_ORDER | default MAX_ORDER | # ----+-------------------+--------------+-----------------+--------------------+ -# 4K | 27 | 12 | 16 | 11 | -# 16K | 27 | 14 | 14 | 12 | -# 64K | 29 | 16 | 14 | 14 | +# 4K | 27 | 12 | 15 | 10 | +# 16K | 27 | 14 | 13 | 11 | +# 64K | 29 | 16 | 13 | 13 | config ARCH_FORCE_MAX_ORDER int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES - default "14" if ARM64_64K_PAGES - range 12 14 if ARM64_16K_PAGES - default "12" if ARM64_16K_PAGES - range 11 16 if ARM64_4K_PAGES - default "11" + default "13" if ARM64_64K_PAGES + range 11 13 if ARM64_16K_PAGES + default "11" if ARM64_16K_PAGES + range 10 15 if ARM64_4K_PAGES + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -1500,14 +1500,11 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - We make sure that we can allocate up to a HugePage size for each configuration. Hence we have : - MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2 + MAX_ORDER = PMD_SHIFT - PAGE_SHIFT => PAGE_SHIFT - 3 - However for 4K, we choose a higher default value, 11 as opposed to 10, giving us + However for 4K, we choose a higher default value, 10 as opposed to 9, giving us 4M allocations matching the default size used by generic code. config UNMAP_KERNEL_AT_EL0 diff --git a/arch/arm64/include/asm/sparsemem.h b/arch/arm64/include/asm/sparsemem.h index 4b73463423c3..5f5437621029 100644 --- a/arch/arm64/include/asm/sparsemem.h +++ b/arch/arm64/include/asm/sparsemem.h @@ -10,7 +10,7 @@ /* * Section size must be at least 512MB for 64K base * page size config. Otherwise it will be less than - * (MAX_ORDER - 1) and the build process will fail. + * MAX_ORDER and the build process will fail. */ #ifdef CONFIG_ARM64_64K_PAGES #define SECTION_SIZE_BITS 29 diff --git a/arch/arm64/kvm/hyp/include/nvhe/gfp.h b/arch/arm64/kvm/hyp/include/nvhe/gfp.h index 0a048dc06a7d..fe5472a184a3 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/gfp.h +++ b/arch/arm64/kvm/hyp/include/nvhe/gfp.h @@ -16,7 +16,7 @@ struct hyp_pool { * API at EL2. */ hyp_spinlock_t lock; - struct list_head free_area[MAX_ORDER]; + struct list_head free_area[MAX_ORDER + 1]; phys_addr_t range_start; phys_addr_t range_end; unsigned short max_order; diff --git a/arch/arm64/kvm/hyp/nvhe/page_alloc.c b/arch/arm64/kvm/hyp/nvhe/page_alloc.c index 803ba3222e75..b1e392186a0f 100644 --- a/arch/arm64/kvm/hyp/nvhe/page_alloc.c +++ b/arch/arm64/kvm/hyp/nvhe/page_alloc.c @@ -110,7 +110,7 @@ static void __hyp_attach_page(struct hyp_pool *pool, * after coalescing, so make sure to mark it HYP_NO_ORDER proactively. */ p->order = HYP_NO_ORDER; - for (; (order + 1) < pool->max_order; order++) { + for (; (order + 1) <= pool->max_order; order++) { buddy = __find_buddy_avail(pool, p, order); if (!buddy) break; @@ -203,9 +203,9 @@ void *hyp_alloc_pages(struct hyp_pool *pool, unsigned short order) hyp_spin_lock(&pool->lock); /* Look for a high-enough-order page */ - while (i < pool->max_order && list_empty(&pool->free_area[i])) + while (i <= pool->max_order && list_empty(&pool->free_area[i])) i++; - if (i >= pool->max_order) { + if (i > pool->max_order) { hyp_spin_unlock(&pool->lock); return NULL; } @@ -228,8 +228,8 @@ int hyp_pool_init(struct hyp_pool *pool, u64 pfn, unsigned int nr_pages, int i; hyp_spin_lock_init(&pool->lock); - pool->max_order = min(MAX_ORDER, get_order((nr_pages + 1) << PAGE_SHIFT)); - for (i = 0; i < pool->max_order; i++) + pool->max_order = min(MAX_ORDER, get_order(nr_pages << PAGE_SHIFT)); + for (i = 0; i <= pool->max_order; i++) INIT_LIST_HEAD(&pool->free_area[i]); pool->range_start = phys; pool->range_end = phys + (nr_pages << PAGE_SHIFT); diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig index dba02da6fa34..c694fac43bed 100644 --- a/arch/csky/Kconfig +++ b/arch/csky/Kconfig @@ -334,7 +334,7 @@ config HIGHMEM config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "11" + default "10" config DRAM_BASE hex "DRAM start addr (the same with memory-section in dts)" diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index d7e4a24e8644..0d2f41fa56ee 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -202,10 +202,10 @@ config IA64_CYCLONE If you're unsure, answer N. config ARCH_FORCE_MAX_ORDER - int "MAX_ORDER (11 - 17)" if !HUGETLB_PAGE - range 11 17 if !HUGETLB_PAGE - default "17" if HUGETLB_PAGE - default "11" + int "MAX_ORDER (10 - 16)" if !HUGETLB_PAGE + range 10 16 if !HUGETLB_PAGE + default "16" if HUGETLB_PAGE + default "10" config SMP bool "Symmetric multi-processing support" diff --git a/arch/ia64/include/asm/sparsemem.h b/arch/ia64/include/asm/sparsemem.h index 84e8ce387b69..a58f8b466d96 100644 --- a/arch/ia64/include/asm/sparsemem.h +++ b/arch/ia64/include/asm/sparsemem.h @@ -12,9 +12,9 @@ #define SECTION_SIZE_BITS (30) #define MAX_PHYSMEM_BITS (50) #ifdef CONFIG_ARCH_FORCE_MAX_ORDER -#if ((CONFIG_ARCH_FORCE_MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS) +#if (CONFIG_ARCH_FORCE_MAX_ORDER + PAGE_SHIFT > SECTION_SIZE_BITS) #undef SECTION_SIZE_BITS -#define SECTION_SIZE_BITS (CONFIG_ARCH_FORCE_MAX_ORDER - 1 + PAGE_SHIFT) +#define SECTION_SIZE_BITS (CONFIG_ARCH_FORCE_MAX_ORDER + PAGE_SHIFT) #endif #endif diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c index 380d2f3966c9..e8dd4323fb86 100644 --- a/arch/ia64/mm/hugetlbpage.c +++ b/arch/ia64/mm/hugetlbpage.c @@ -170,7 +170,7 @@ static int __init hugetlb_setup_sz(char *str) size = memparse(str, &str); if (*str || !is_power_of_2(size) || !(tr_pages & size) || size <= PAGE_SIZE || - size >= (1UL << PAGE_SHIFT << MAX_ORDER)) { + size > (1UL << PAGE_SHIFT << MAX_ORDER)) { printk(KERN_WARNING "Invalid huge page size specified\n"); return 1; } diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 7fd51257e0ed..272a3a12c98d 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -420,12 +420,12 @@ config NODES_SHIFT config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 14 64 if PAGE_SIZE_64KB - default "14" if PAGE_SIZE_64KB - range 12 64 if PAGE_SIZE_16KB - default "12" if PAGE_SIZE_16KB - range 11 64 - default "11" + range 13 63 if PAGE_SIZE_64KB + default "13" if PAGE_SIZE_64KB + range 11 63 if PAGE_SIZE_16KB + default "11" if PAGE_SIZE_16KB + range 10 63 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -434,9 +434,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. Keep this in mind when choosing a value for this option. diff --git a/arch/m68k/Kconfig.cpu b/arch/m68k/Kconfig.cpu index 9380f6e3bb66..c9df6572133f 100644 --- a/arch/m68k/Kconfig.cpu +++ b/arch/m68k/Kconfig.cpu @@ -400,7 +400,7 @@ config SINGLE_MEMORY_CHUNK config ARCH_FORCE_MAX_ORDER int "Maximum zone order" if ADVANCED depends on !SINGLE_MEMORY_CHUNK - default "11" + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -413,9 +413,6 @@ config ARCH_FORCE_MAX_ORDER value also defines the minimal size of the hole that allows freeing unused memory map. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - config 060_WRITETHROUGH bool "Use write-through caching for 68060 supervisor accesses" depends on ADVANCED && M68060 diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index e2f3ca73f40d..3e8b765b8c7b 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -2137,14 +2137,14 @@ endchoice config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 14 64 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB - default "14" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB - range 13 64 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB - default "13" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB - range 12 64 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB - default "12" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB - range 0 64 - default "11" + range 13 63 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB + default "13" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB + range 12 63 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB + default "12" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB + range 11 63 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB + default "11" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB + range 0 63 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -2153,9 +2153,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. Keep this in mind when choosing a value for this option. diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig index a582f72104f3..89708b95978c 100644 --- a/arch/nios2/Kconfig +++ b/arch/nios2/Kconfig @@ -46,8 +46,8 @@ source "kernel/Kconfig.hz" config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 9 20 - default "11" + range 8 19 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -56,9 +56,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - endmenu source "arch/nios2/platform/Kconfig.platform" diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 49c6d36b2b3e..24d56536b269 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -897,18 +897,18 @@ config DATA_SHIFT config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 8 9 if PPC64 && PPC_64K_PAGES - default "9" if PPC64 && PPC_64K_PAGES - range 13 13 if PPC64 && !PPC_64K_PAGES - default "13" if PPC64 && !PPC_64K_PAGES - range 9 64 if PPC32 && PPC_16K_PAGES - default "9" if PPC32 && PPC_16K_PAGES - range 7 64 if PPC32 && PPC_64K_PAGES - default "7" if PPC32 && PPC_64K_PAGES - range 5 64 if PPC32 && PPC_256K_PAGES - default "5" if PPC32 && PPC_256K_PAGES - range 11 64 - default "11" + range 7 8 if PPC64 && PPC_64K_PAGES + default "8" if PPC64 && PPC_64K_PAGES + range 12 12 if PPC64 && !PPC_64K_PAGES + default "12" if PPC64 && !PPC_64K_PAGES + range 8 63 if PPC32 && PPC_16K_PAGES + default "8" if PPC32 && PPC_16K_PAGES + range 6 63 if PPC32 && PPC_64K_PAGES + default "6" if PPC32 && PPC_64K_PAGES + range 4 63 if PPC32 && PPC_256K_PAGES + default "4" if PPC32 && PPC_256K_PAGES + range 10 63 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -917,9 +917,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. For example, on 64-bit systems, 64KB pages can be enabled via CONFIG_PPC_64K_PAGES. Keep this in mind when choosing a value for this option. diff --git a/arch/powerpc/configs/85xx/ge_imp3a_defconfig b/arch/powerpc/configs/85xx/ge_imp3a_defconfig index ea719898b581..6cb7e90d52c1 100644 --- a/arch/powerpc/configs/85xx/ge_imp3a_defconfig +++ b/arch/powerpc/configs/85xx/ge_imp3a_defconfig @@ -30,7 +30,7 @@ CONFIG_PREEMPT=y # CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS is not set CONFIG_BINFMT_MISC=m CONFIG_MATH_EMULATION=y -CONFIG_ARCH_FORCE_MAX_ORDER=17 +CONFIG_ARCH_FORCE_MAX_ORDER=16 CONFIG_PCI=y CONFIG_PCIEPORTBUS=y CONFIG_PCI_MSI=y diff --git a/arch/powerpc/configs/fsl-emb-nonhw.config b/arch/powerpc/configs/fsl-emb-nonhw.config index ab8a8c4530d9..3009b0efaf34 100644 --- a/arch/powerpc/configs/fsl-emb-nonhw.config +++ b/arch/powerpc/configs/fsl-emb-nonhw.config @@ -41,7 +41,7 @@ CONFIG_FIXED_PHY=y CONFIG_FONT_8x16=y CONFIG_FONT_8x8=y CONFIG_FONTS=y -CONFIG_ARCH_FORCE_MAX_ORDER=13 +CONFIG_ARCH_FORCE_MAX_ORDER=12 CONFIG_FRAMEBUFFER_CONSOLE=y CONFIG_FRAME_WARN=1024 CONFIG_FTL=y diff --git a/arch/powerpc/mm/book3s64/iommu_api.c b/arch/powerpc/mm/book3s64/iommu_api.c index 7fcfba162e0d..81d7185e2ae8 100644 --- a/arch/powerpc/mm/book3s64/iommu_api.c +++ b/arch/powerpc/mm/book3s64/iommu_api.c @@ -97,7 +97,7 @@ static long mm_iommu_do_alloc(struct mm_struct *mm, unsigned long ua, } mmap_read_lock(mm); - chunk = (1UL << (PAGE_SHIFT + MAX_ORDER - 1)) / + chunk = (1UL << (PAGE_SHIFT + MAX_ORDER)) / sizeof(struct vm_area_struct *); chunk = min(chunk, entries); for (entry = 0; entry < entries; entry += chunk) { diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index f1ba8d1e8c1a..b900933507da 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -615,7 +615,7 @@ void __init gigantic_hugetlb_cma_reserve(void) order = mmu_psize_to_shift(MMU_PAGE_16G) - PAGE_SHIFT; if (order) { - VM_WARN_ON(order < MAX_ORDER); + VM_WARN_ON(order <= MAX_ORDER); hugetlb_cma_reserve(order); } } diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index 4f6e20a35aa1..5a81f106068e 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda.c +++ b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -1740,7 +1740,7 @@ static long pnv_pci_ioda2_setup_default_config(struct pnv_ioda_pe *pe) * DMA window can be larger than available memory, which will * cause errors later. */ - const u64 maxblock = 1UL << (PAGE_SHIFT + MAX_ORDER - 1); + const u64 maxblock = 1UL << (PAGE_SHIFT + MAX_ORDER); /* * We create the default window as big as we can. The constraint is diff --git a/arch/sh/configs/ecovec24_defconfig b/arch/sh/configs/ecovec24_defconfig index b52e14ccb450..4d655e8d4d74 100644 --- a/arch/sh/configs/ecovec24_defconfig +++ b/arch/sh/configs/ecovec24_defconfig @@ -8,7 +8,7 @@ CONFIG_MODULES=y CONFIG_MODULE_UNLOAD=y # CONFIG_BLK_DEV_BSG is not set CONFIG_CPU_SUBTYPE_SH7724=y -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_MEMORY_SIZE=0x10000000 CONFIG_FLATMEM_MANUAL=y CONFIG_SH_ECOVEC=y diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig index 411fdc0901f7..40271090bd7d 100644 --- a/arch/sh/mm/Kconfig +++ b/arch/sh/mm/Kconfig @@ -20,13 +20,13 @@ config PAGE_OFFSET config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 9 64 if PAGE_SIZE_16KB - default "9" if PAGE_SIZE_16KB - range 7 64 if PAGE_SIZE_64KB - default "7" if PAGE_SIZE_64KB - range 11 64 - default "14" if !MMU - default "11" + range 8 63 if PAGE_SIZE_16KB + default "8" if PAGE_SIZE_16KB + range 6 63 if PAGE_SIZE_64KB + default "6" if PAGE_SIZE_64KB + range 10 63 + default "13" if !MMU + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -35,9 +35,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. Keep this in mind when choosing a value for this option. diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 84437a4c6545..e3242bf5a8df 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -271,7 +271,7 @@ config ARCH_SPARSEMEM_DEFAULT config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "13" + default "12" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -280,9 +280,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 13 means that the largest free memory block is 2^12 pages. - if SPARC64 || COMPILE_TEST source "kernel/power/Kconfig" endif diff --git a/arch/sparc/kernel/pci_sun4v.c b/arch/sparc/kernel/pci_sun4v.c index 384480971805..7d91ca6aa675 100644 --- a/arch/sparc/kernel/pci_sun4v.c +++ b/arch/sparc/kernel/pci_sun4v.c @@ -193,7 +193,7 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size, size = IO_PAGE_ALIGN(size); order = get_order(size); - if (unlikely(order >= MAX_ORDER)) + if (unlikely(order > MAX_ORDER)) return NULL; npages = size >> IO_PAGE_SHIFT; diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c index 5b4de4a89dec..08ffd17d5ec3 100644 --- a/arch/sparc/kernel/traps_64.c +++ b/arch/sparc/kernel/traps_64.c @@ -897,7 +897,7 @@ void __init cheetah_ecache_flush_init(void) /* Now allocate error trap reporting scoreboard. */ sz = NR_CPUS * (2 * sizeof(struct cheetah_err_info)); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { if ((PAGE_SIZE << order) >= sz) break; } diff --git a/arch/sparc/mm/tsb.c b/arch/sparc/mm/tsb.c index dba8dffe2113..5e2931a18409 100644 --- a/arch/sparc/mm/tsb.c +++ b/arch/sparc/mm/tsb.c @@ -402,8 +402,8 @@ void tsb_grow(struct mm_struct *mm, unsigned long tsb_index, unsigned long rss) unsigned long new_rss_limit; gfp_t gfp_flags; - if (max_tsb_size > (PAGE_SIZE << (MAX_ORDER - 1))) - max_tsb_size = (PAGE_SIZE << (MAX_ORDER - 1)); + if (max_tsb_size > PAGE_SIZE << MAX_ORDER) + max_tsb_size = PAGE_SIZE << MAX_ORDER; new_cache_index = 0; for (new_size = 8192; new_size < max_tsb_size; new_size <<= 1UL) { diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index 5e5a9c8e0e5d..8dcda617b8bf 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -368,10 +368,10 @@ int __init linux_main(int argc, char **argv) max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC; /* - * Zones have to begin on a 1 << MAX_ORDER-1 page boundary, + * Zones have to begin on a 1 << MAX_ORDER page boundary, * so this makes sure that's true for highmem */ - max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER - 1)) - 1); + max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1); if (physmem_size + iomem_size > max_physmem) { highmem = physmem_size + iomem_size - max_physmem; physmem_size -= highmem; diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index bcb0c5d2abc2..3eee334ba873 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -773,7 +773,7 @@ config HIGHMEM config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "11" + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -782,9 +782,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - endmenu menu "Power management options" diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index 817eda2075aa..c491fabe3617 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -226,8 +226,8 @@ static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from, if (*ppos < 0 || !count) return -EINVAL; - if (count > (PAGE_SIZE << (MAX_ORDER - 1))) - count = PAGE_SIZE << (MAX_ORDER - 1); + if (count > (PAGE_SIZE << MAX_ORDER)) + count = PAGE_SIZE << MAX_ORDER; buf = kmalloc(count, GFP_KERNEL); if (!buf) @@ -373,8 +373,8 @@ static ssize_t regmap_reg_ranges_read_file(struct file *file, if (*ppos < 0 || !count) return -EINVAL; - if (count > (PAGE_SIZE << (MAX_ORDER - 1))) - count = PAGE_SIZE << (MAX_ORDER - 1); + if (count > (PAGE_SIZE << MAX_ORDER)) + count = PAGE_SIZE << MAX_ORDER; buf = kmalloc(count, GFP_KERNEL); if (!buf) diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 90d2dfb6448e..cec2c20f5e59 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -3079,7 +3079,7 @@ static void raw_cmd_free(struct floppy_raw_cmd **ptr) } } -#define MAX_LEN (1UL << (MAX_ORDER - 1) << PAGE_SHIFT) +#define MAX_LEN (1UL << MAX_ORDER << PAGE_SHIFT) static int raw_cmd_copyin(int cmd, void __user *param, struct floppy_raw_cmd **rcmd) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index e2f25926eb51..bf095baca244 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -886,7 +886,7 @@ static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) /* * The length of the ID shouldn't be assumed by software since * it may change in the future. The allocation size is limited - * to 1 << (PAGE_SHIFT + MAX_ORDER - 1) by the page allocator. + * to 1 << (PAGE_SHIFT + MAX_ORDER) by the page allocator. * If the allocation fails, simply return ENOMEM rather than * warning in the kernel log. */ diff --git a/drivers/crypto/hisilicon/sgl.c b/drivers/crypto/hisilicon/sgl.c index 09586a837b1e..3df7a256e919 100644 --- a/drivers/crypto/hisilicon/sgl.c +++ b/drivers/crypto/hisilicon/sgl.c @@ -70,11 +70,11 @@ struct hisi_acc_sgl_pool *hisi_acc_create_sgl_pool(struct device *dev, HISI_ACC_SGL_ALIGN_SIZE); /* - * the pool may allocate a block of memory of size PAGE_SIZE * 2^(MAX_ORDER - 1), + * the pool may allocate a block of memory of size PAGE_SIZE * 2^MAX_ORDER, * block size may exceed 2^31 on ia64, so the max of block size is 2^31 */ - block_size = 1 << (PAGE_SHIFT + MAX_ORDER <= 32 ? - PAGE_SHIFT + MAX_ORDER - 1 : 31); + block_size = 1 << (PAGE_SHIFT + MAX_ORDER < 32 ? + PAGE_SHIFT + MAX_ORDER : 31); sgl_num_per_block = block_size / sgl_size; block_num = count / sgl_num_per_block; remain_sgl = count % sgl_num_per_block; diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c index eae9e9f6d3bf..6bc26b4b06b8 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c @@ -36,7 +36,7 @@ static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj) struct sg_table *st; struct scatterlist *sg; unsigned int npages; /* restricted by sg_alloc_table */ - int max_order = MAX_ORDER - 1; + int max_order = MAX_ORDER; unsigned int max_segment; gfp_t gfp; diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c index defece0bcb81..99f39a5feca1 100644 --- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c +++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c @@ -115,7 +115,7 @@ static int get_huge_pages(struct drm_i915_gem_object *obj) do { struct page *page; - GEM_BUG_ON(order >= MAX_ORDER); + GEM_BUG_ON(order > MAX_ORDER); page = alloc_pages(GFP | __GFP_ZERO, order); if (!page) goto err; diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c index aa116a7bbae3..6c8585abe08d 100644 --- a/drivers/gpu/drm/ttm/ttm_pool.c +++ b/drivers/gpu/drm/ttm/ttm_pool.c @@ -65,11 +65,11 @@ module_param(page_pool_size, ulong, 0644); static atomic_long_t allocated_pages; -static struct ttm_pool_type global_write_combined[MAX_ORDER]; -static struct ttm_pool_type global_uncached[MAX_ORDER]; +static struct ttm_pool_type global_write_combined[MAX_ORDER + 1]; +static struct ttm_pool_type global_uncached[MAX_ORDER + 1]; -static struct ttm_pool_type global_dma32_write_combined[MAX_ORDER]; -static struct ttm_pool_type global_dma32_uncached[MAX_ORDER]; +static struct ttm_pool_type global_dma32_write_combined[MAX_ORDER + 1]; +static struct ttm_pool_type global_dma32_uncached[MAX_ORDER + 1]; static spinlock_t shrinker_lock; static struct list_head shrinker_list; @@ -405,7 +405,7 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, else gfp_flags |= GFP_HIGHUSER; - for (order = min_t(unsigned int, MAX_ORDER - 1, __fls(num_pages)); + for (order = min_t(unsigned int, MAX_ORDER, __fls(num_pages)); num_pages; order = min_t(unsigned int, order, __fls(num_pages))) { struct ttm_pool_type *pt; @@ -542,7 +542,7 @@ void ttm_pool_init(struct ttm_pool *pool, struct device *dev, if (use_dma_alloc) { for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) - for (j = 0; j < MAX_ORDER; ++j) + for (j = 0; j <= MAX_ORDER; ++j) ttm_pool_type_init(&pool->caching[i].orders[j], pool, i, j); } @@ -562,7 +562,7 @@ void ttm_pool_fini(struct ttm_pool *pool) if (pool->use_dma_alloc) { for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) - for (j = 0; j < MAX_ORDER; ++j) + for (j = 0; j <= MAX_ORDER; ++j) ttm_pool_type_fini(&pool->caching[i].orders[j]); } @@ -616,7 +616,7 @@ static void ttm_pool_debugfs_header(struct seq_file *m) unsigned int i; seq_puts(m, "\t "); - for (i = 0; i < MAX_ORDER; ++i) + for (i = 0; i <= MAX_ORDER; ++i) seq_printf(m, " ---%2u---", i); seq_puts(m, "\n"); } @@ -627,7 +627,7 @@ static void ttm_pool_debugfs_orders(struct ttm_pool_type *pt, { unsigned int i; - for (i = 0; i < MAX_ORDER; ++i) + for (i = 0; i <= MAX_ORDER; ++i) seq_printf(m, " %8u", ttm_pool_type_count(&pt[i])); seq_puts(m, "\n"); } @@ -736,7 +736,7 @@ int ttm_pool_mgr_init(unsigned long num_pages) spin_lock_init(&shrinker_lock); INIT_LIST_HEAD(&shrinker_list); - for (i = 0; i < MAX_ORDER; ++i) { + for (i = 0; i <= MAX_ORDER; ++i) { ttm_pool_type_init(&global_write_combined[i], NULL, ttm_write_combined, i); ttm_pool_type_init(&global_uncached[i], NULL, ttm_uncached, i); @@ -769,7 +769,7 @@ void ttm_pool_mgr_fini(void) { unsigned int i; - for (i = 0; i < MAX_ORDER; ++i) { + for (i = 0; i <= MAX_ORDER; ++i) { ttm_pool_type_fini(&global_write_combined[i]); ttm_pool_type_fini(&global_uncached[i]); diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index 8d772ea8a583..b574c58a3487 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -182,7 +182,7 @@ #ifdef CONFIG_CMA_ALIGNMENT #define Q_MAX_SZ_SHIFT (PAGE_SHIFT + CONFIG_CMA_ALIGNMENT) #else -#define Q_MAX_SZ_SHIFT (PAGE_SHIFT + MAX_ORDER - 1) +#define Q_MAX_SZ_SHIFT (PAGE_SHIFT + MAX_ORDER) #endif /* diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index ac996fd6bd9c..7a9f0b0bddbd 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -736,7 +736,7 @@ static struct page **__iommu_dma_alloc_pages(struct device *dev, struct page **pages; unsigned int i = 0, nid = dev_to_node(dev); - order_mask &= GENMASK(MAX_ORDER - 1, 0); + order_mask &= GENMASK(MAX_ORDER, 0); if (!order_mask) return NULL; diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 586271b8aa39..85790b870877 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -2440,8 +2440,8 @@ static bool its_parse_indirect_baser(struct its_node *its, * feature is not supported by hardware. */ new_order = max_t(u32, get_order(esz << ids), new_order); - if (new_order >= MAX_ORDER) { - new_order = MAX_ORDER - 1; + if (new_order > MAX_ORDER) { + new_order = MAX_ORDER; ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz); pr_warn("ITS@%pa: %s Table too large, reduce ids %llu->%u\n", &its->phys_base, its_base_type_string[type], diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index cf077f9b30c3..733053c2eaa0 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -408,7 +408,7 @@ static void __cache_size_refresh(void) * If the allocation may fail we use __get_free_pages. Memory fragmentation * won't have a fatal effect here, but it just causes flushes of some other * buffers and more I/O will be performed. Don't use __get_free_pages if it - * always fails (i.e. order >= MAX_ORDER). + * always fails (i.e. order > MAX_ORDER). * * If the allocation shouldn't fail we use __vmalloc. This is only for the * initial reserve allocation, so there's no risk of wasting all vmalloc diff --git a/drivers/misc/genwqe/card_dev.c b/drivers/misc/genwqe/card_dev.c index d0e27438a73c..55fc5b80e649 100644 --- a/drivers/misc/genwqe/card_dev.c +++ b/drivers/misc/genwqe/card_dev.c @@ -443,7 +443,7 @@ static int genwqe_mmap(struct file *filp, struct vm_area_struct *vma) if (vsize == 0) return -EINVAL; - if (get_order(vsize) >= MAX_ORDER) + if (get_order(vsize) > MAX_ORDER) return -ENOMEM; dma_map = kzalloc(sizeof(struct dma_mapping), GFP_KERNEL); diff --git a/drivers/misc/genwqe/card_utils.c b/drivers/misc/genwqe/card_utils.c index ac29698d085a..1c798d6b2dfb 100644 --- a/drivers/misc/genwqe/card_utils.c +++ b/drivers/misc/genwqe/card_utils.c @@ -210,7 +210,7 @@ u32 genwqe_crc32(u8 *buff, size_t len, u32 init) void *__genwqe_alloc_consistent(struct genwqe_dev *cd, size_t size, dma_addr_t *dma_handle) { - if (get_order(size) >= MAX_ORDER) + if (get_order(size) > MAX_ORDER) return NULL; return dma_alloc_coherent(&cd->pci_dev->dev, size, dma_handle, @@ -308,7 +308,7 @@ int genwqe_alloc_sync_sgl(struct genwqe_dev *cd, struct genwqe_sgl *sgl, sgl->write = write; sgl->sgl_size = genwqe_sgl_size(sgl->nr_pages); - if (get_order(sgl->sgl_size) >= MAX_ORDER) { + if (get_order(sgl->sgl_size) > MAX_ORDER) { dev_err(&pci_dev->dev, "[%s] err: too much memory requested!\n", __func__); return ret; diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c index 25be7f8ac7cd..3973ca6adf4c 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -1041,7 +1041,7 @@ static void hns3_init_tx_spare_buffer(struct hns3_enet_ring *ring) return; order = get_order(alloc_size); - if (order >= MAX_ORDER) { + if (order > MAX_ORDER) { if (net_ratelimit()) dev_warn(ring_to_dev(ring), "failed to allocate tx spare buffer, exceed to max order\n"); return; diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h index b35c9b6f913b..4e18b4cefa97 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.h +++ b/drivers/net/ethernet/ibm/ibmvnic.h @@ -75,7 +75,7 @@ * pool for the 4MB. Thus the 16 Rx and Tx queues require 32 * 5 = 160 * plus 16 for the TSO pools for a total of 176 LTB mappings per VNIC. */ -#define IBMVNIC_ONE_LTB_MAX ((u32)((1 << (MAX_ORDER - 1)) * PAGE_SIZE)) +#define IBMVNIC_ONE_LTB_MAX ((u32)((1 << MAX_ORDER) * PAGE_SIZE)) #define IBMVNIC_ONE_LTB_SIZE min((u32)(8 << 20), IBMVNIC_ONE_LTB_MAX) #define IBMVNIC_LTB_SET_SIZE (38 << 20) diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c index ec3f6cf05f8c..34781dec3856 100644 --- a/drivers/video/fbdev/hyperv_fb.c +++ b/drivers/video/fbdev/hyperv_fb.c @@ -946,7 +946,7 @@ static phys_addr_t hvfb_get_phymem(struct hv_device *hdev, if (request_size == 0) return -1; - if (order < MAX_ORDER) { + if (order <= MAX_ORDER) { /* Call alloc_pages if the size is less than 2^MAX_ORDER */ page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); if (!page) @@ -977,7 +977,7 @@ static void hvfb_release_phymem(struct hv_device *hdev, { unsigned int order = get_order(size); - if (order < MAX_ORDER) + if (order <= MAX_ORDER) __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order); else dma_free_coherent(&hdev->device, diff --git a/drivers/video/fbdev/vermilion/vermilion.c b/drivers/video/fbdev/vermilion/vermilion.c index 0374ee6b6d03..32e74e02a02f 100644 --- a/drivers/video/fbdev/vermilion/vermilion.c +++ b/drivers/video/fbdev/vermilion/vermilion.c @@ -197,7 +197,7 @@ static int vmlfb_alloc_vram(struct vml_info *vinfo, va = &vinfo->vram[i]; order = 0; - while (requested > (PAGE_SIZE << order) && order < MAX_ORDER) + while (requested > (PAGE_SIZE << order) && order <= MAX_ORDER) order++; err = vmlfb_alloc_vram_area(va, order, 0); diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 3f78a3a1eb75..5b15936a5214 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -33,7 +33,7 @@ #define VIRTIO_BALLOON_FREE_PAGE_ALLOC_FLAG (__GFP_NORETRY | __GFP_NOWARN | \ __GFP_NOMEMALLOC) /* The order of free page blocks to report to host */ -#define VIRTIO_BALLOON_HINT_BLOCK_ORDER (MAX_ORDER - 1) +#define VIRTIO_BALLOON_HINT_BLOCK_ORDER MAX_ORDER /* The size of a free page block in bytes */ #define VIRTIO_BALLOON_HINT_BLOCK_BYTES \ (1 << (VIRTIO_BALLOON_HINT_BLOCK_ORDER + PAGE_SHIFT)) diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c index 0c2892ec6817..835f6cc2fb66 100644 --- a/drivers/virtio/virtio_mem.c +++ b/drivers/virtio/virtio_mem.c @@ -1120,13 +1120,13 @@ static void virtio_mem_clear_fake_offline(unsigned long pfn, */ static void virtio_mem_fake_online(unsigned long pfn, unsigned long nr_pages) { - unsigned long order = MAX_ORDER - 1; + unsigned long order = MAX_ORDER; unsigned long i; /* * We might get called for ranges that don't cover properly aligned - * MAX_ORDER - 1 pages; however, we can only online properly aligned - * pages with an order of MAX_ORDER - 1 at maximum. + * MAX_ORDER pages; however, we can only online properly aligned + * pages with an order of MAX_ORDER at maximum. */ while (!IS_ALIGNED(pfn | nr_pages, 1 << order)) order--; @@ -1237,9 +1237,9 @@ static void virtio_mem_online_page(struct virtio_mem *vm, bool do_online; /* - * We can get called with any order up to MAX_ORDER - 1. If our - * subblock size is smaller than that and we have a mixture of plugged - * and unplugged subblocks within such a page, we have to process in + * We can get called with any order up to MAX_ORDER. If our subblock + * size is smaller than that and we have a mixture of plugged and + * unplugged subblocks within such a page, we have to process in * smaller granularity. In that case we'll adjust the order exactly once * within the loop. */ diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c index 2f67516bb9bf..9fbb9b5256f7 100644 --- a/fs/ramfs/file-nommu.c +++ b/fs/ramfs/file-nommu.c @@ -70,7 +70,7 @@ int ramfs_nommu_expand_for_mapping(struct inode *inode, size_t newsize) /* make various checks */ order = get_order(newsize); - if (unlikely(order >= MAX_ORDER)) + if (unlikely(order > MAX_ORDER)) return -EFBIG; ret = inode_newsize_ok(inode, newsize); diff --git a/include/drm/ttm/ttm_pool.h b/include/drm/ttm/ttm_pool.h index ef09b23d29e3..8ce14f9d202a 100644 --- a/include/drm/ttm/ttm_pool.h +++ b/include/drm/ttm/ttm_pool.h @@ -72,7 +72,7 @@ struct ttm_pool { bool use_dma32; struct { - struct ttm_pool_type orders[MAX_ORDER]; + struct ttm_pool_type orders[MAX_ORDER + 1]; } caching[TTM_NUM_CACHING_TYPES]; }; diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 7c977d234aba..8fb7d91cd0b1 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -818,7 +818,7 @@ static inline unsigned huge_page_shift(struct hstate *h) static inline bool hstate_is_gigantic(struct hstate *h) { - return huge_page_order(h) >= MAX_ORDER; + return huge_page_order(h) > MAX_ORDER; } static inline unsigned int pages_per_huge_page(const struct hstate *h) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index bf8786d45b31..35b11cc210d9 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -26,11 +26,11 @@ /* Free memory management - zoned buddy allocator. */ #ifndef CONFIG_ARCH_FORCE_MAX_ORDER -#define MAX_ORDER 11 +#define MAX_ORDER 10 #else #define MAX_ORDER CONFIG_ARCH_FORCE_MAX_ORDER #endif -#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1)) +#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER) /* * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed @@ -93,7 +93,7 @@ static inline bool migratetype_is_mergeable(int mt) } #define for_each_migratetype_order(order, type) \ - for (order = 0; order < MAX_ORDER; order++) \ + for (order = 0; order <= MAX_ORDER; order++) \ for (type = 0; type < MIGRATE_TYPES; type++) extern int page_group_by_mobility_disabled; @@ -922,7 +922,7 @@ struct zone { CACHELINE_PADDING(_pad1_); /* free areas of different sizes */ - struct free_area free_area[MAX_ORDER]; + struct free_area free_area[MAX_ORDER + 1]; /* zone flags, see below */ unsigned long flags; @@ -1745,7 +1745,7 @@ static inline bool movable_only_nodes(nodemask_t *nodes) #define SECTION_BLOCKFLAGS_BITS \ ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS) -#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS +#if (MAX_ORDER + PAGE_SHIFT) > SECTION_SIZE_BITS #error Allocator MAX_ORDER exceeds SECTION_SIZE #endif diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h index 5f1ae07d724b..e83c4c095041 100644 --- a/include/linux/pageblock-flags.h +++ b/include/linux/pageblock-flags.h @@ -41,14 +41,14 @@ extern unsigned int pageblock_order; * Huge pages are a constant size, but don't exceed the maximum allocation * granularity. */ -#define pageblock_order min_t(unsigned int, HUGETLB_PAGE_ORDER, MAX_ORDER - 1) +#define pageblock_order min_t(unsigned int, HUGETLB_PAGE_ORDER, MAX_ORDER) #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ #else /* CONFIG_HUGETLB_PAGE */ /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */ -#define pageblock_order (MAX_ORDER-1) +#define pageblock_order MAX_ORDER #endif /* CONFIG_HUGETLB_PAGE */ diff --git a/include/linux/slab.h b/include/linux/slab.h index 45af70315a94..aa4575ef2965 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -284,7 +284,7 @@ static inline unsigned int arch_slab_minalign(void) * (PAGE_SIZE*2). Larger requests are passed to the page allocator. */ #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 5 #endif @@ -292,7 +292,7 @@ static inline unsigned int arch_slab_minalign(void) #ifdef CONFIG_SLUB #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 3 #endif @@ -305,7 +305,7 @@ static inline unsigned int arch_slab_minalign(void) * be allocated from the same page. */ #define KMALLOC_SHIFT_HIGH PAGE_SHIFT -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 3 #endif diff --git a/kernel/crash_core.c b/kernel/crash_core.c index 755f5f08ab38..90ce1dfd591c 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -474,7 +474,7 @@ static int __init crash_save_vmcoreinfo_init(void) VMCOREINFO_OFFSET(list_head, prev); VMCOREINFO_OFFSET(vmap_area, va_start); VMCOREINFO_OFFSET(vmap_area, list); - VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER); + VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER + 1); log_buf_vmcoreinfo_setup(); VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES); VMCOREINFO_NUMBER(NR_FREE_PAGES); diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 4d40dcce7604..1acec2e22827 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -84,8 +84,8 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, void *addr; int ret = -ENOMEM; - /* Cannot allocate larger than MAX_ORDER-1 */ - order = min(get_order(pool_size), MAX_ORDER-1); + /* Cannot allocate larger than MAX_ORDER */ + order = min(get_order(pool_size), MAX_ORDER); do { pool_size = 1 << (PAGE_SHIFT + order); @@ -190,7 +190,7 @@ static int __init dma_atomic_pool_init(void) /* * If coherent_pool was not used on the command line, default the pool - * sizes to 128KB per 1GB of memory, min 128KB, max MAX_ORDER-1. + * sizes to 128KB per 1GB of memory, min 128KB, max MAX_ORDER. */ if (!atomic_pool_size) { unsigned long pages = totalram_pages() / (SZ_1G / SZ_128K); diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index d6bbdb7830b2..a0433f37b024 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -609,8 +609,8 @@ static struct page *rb_alloc_aux_page(int node, int order) { struct page *page; - if (order >= MAX_ORDER) - order = MAX_ORDER - 1; + if (order > MAX_ORDER) + order = MAX_ORDER; do { page = alloc_pages_node(node, PERF_AUX_GFP, order); @@ -814,7 +814,7 @@ struct perf_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags) size = sizeof(struct perf_buffer); size += nr_pages * sizeof(void *); - if (order_base_2(size) >= PAGE_SHIFT+MAX_ORDER) + if (order_base_2(size) > PAGE_SHIFT+MAX_ORDER) goto fail; node = (cpu == -1) ? cpu : cpu_to_node(cpu); diff --git a/mm/Kconfig b/mm/Kconfig index ca98b2072df5..969286ab14a1 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -346,9 +346,9 @@ config SHUFFLE_PAGE_ALLOCATOR the presence of a memory-side-cache. There are also incidental security benefits as it reduces the predictability of page allocations to compliment SLAB_FREELIST_RANDOM, but the - default granularity of shuffling on the "MAX_ORDER - 1" i.e, - 10th order of pages is selected based on cache utilization - benefits on x86. + default granularity of shuffling on the MAX_ORDER i.e, 10th + order of pages is selected based on cache utilization benefits + on x86. While the randomization improves cache utilization it may negatively impact workloads on platforms without a cache. For @@ -666,8 +666,8 @@ config HUGETLB_PAGE_SIZE_VARIABLE HUGETLB_PAGE_ORDER when there are multiple HugeTLB page sizes available on a platform. - Note that the pageblock_order cannot exceed MAX_ORDER - 1 and will be - clamped down to MAX_ORDER - 1. + Note that the pageblock_order cannot exceed MAX_ORDER and will be + clamped down to MAX_ORDER. config CONTIG_ALLOC def_bool (MEMORY_ISOLATION && COMPACTION) || CMA diff --git a/mm/compaction.c b/mm/compaction.c index 5a9501e0ae01..709136556b9e 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -583,7 +583,7 @@ static unsigned long isolate_freepages_block(struct compact_control *cc, if (PageCompound(page)) { const unsigned int order = compound_order(page); - if (likely(order < MAX_ORDER)) { + if (likely(order <= MAX_ORDER)) { blockpfn += (1UL << order) - 1; cursor += (1UL << order) - 1; } @@ -938,7 +938,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, * a valid page order. Consider only values in the * valid order range to prevent low_pfn overflow. */ - if (freepage_order > 0 && freepage_order < MAX_ORDER) + if (freepage_order > 0 && freepage_order <= MAX_ORDER) low_pfn += (1UL << freepage_order) - 1; continue; } @@ -954,7 +954,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, if (PageCompound(page) && !cc->alloc_contig) { const unsigned int order = compound_order(page); - if (likely(order < MAX_ORDER)) + if (likely(order <= MAX_ORDER)) low_pfn += (1UL << order) - 1; goto isolate_fail; } @@ -2124,7 +2124,7 @@ static enum compact_result __compact_finished(struct compact_control *cc) /* Direct compactor: Is a suitable page free? */ ret = COMPACT_NO_SUITABLE_PAGE; - for (order = cc->order; order < MAX_ORDER; order++) { + for (order = cc->order; order <= MAX_ORDER; order++) { struct free_area *area = &cc->zone->free_area[order]; bool can_steal; diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 4362021b1ce7..c54177aabebd 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -1086,7 +1086,7 @@ debug_vm_pgtable_alloc_huge_page(struct pgtable_debug_args *args, int order) struct page *page = NULL; #ifdef CONFIG_CONTIG_ALLOC - if (order >= MAX_ORDER) { + if (order > MAX_ORDER) { page = alloc_contig_pages((1 << order), GFP_KERNEL, first_online_node, NULL); if (page) { @@ -1096,7 +1096,7 @@ debug_vm_pgtable_alloc_huge_page(struct pgtable_debug_args *args, int order) } #endif - if (order < MAX_ORDER) + if (order <= MAX_ORDER) page = alloc_pages(GFP_KERNEL, order); return page; diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 2d860e70fe88..1df386d13d24 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -467,7 +467,7 @@ static int __init hugepage_init(void) /* * hugepages can't be allocated by the buddy allocator */ - MAYBE_BUILD_BUG_ON(HPAGE_PMD_ORDER >= MAX_ORDER); + MAYBE_BUILD_BUG_ON(HPAGE_PMD_ORDER > MAX_ORDER); /* * we use page->mapping and page->index in second tail page * as list_head: assuming THP order >= 2 diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 712e32b38295..9122e50ae02a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2090,7 +2090,7 @@ pgoff_t hugetlb_basepage_index(struct page *page) pgoff_t index = page_index(page_head); unsigned long compound_idx; - if (compound_order(page_head) >= MAX_ORDER) + if (compound_order(page_head) > MAX_ORDER) compound_idx = page_to_pfn(page) - page_to_pfn(page_head); else compound_idx = page - page_head; @@ -4497,7 +4497,7 @@ static int __init default_hugepagesz_setup(char *s) * The number of default huge pages (for this size) could have been * specified as the first hugetlb parameter: hugepages=X. If so, * then default_hstate_max_huge_pages is set. If the default huge - * page size is gigantic (>= MAX_ORDER), then the pages must be + * page size is gigantic (> MAX_ORDER), then the pages must be * allocated here from bootmem allocator. */ if (default_hstate_max_huge_pages) { diff --git a/mm/kmsan/init.c b/mm/kmsan/init.c index 7fb794242fad..ffedf4dbc49d 100644 --- a/mm/kmsan/init.c +++ b/mm/kmsan/init.c @@ -96,7 +96,7 @@ void __init kmsan_init_shadow(void) struct metadata_page_pair { struct page *shadow, *origin; }; -static struct metadata_page_pair held_back[MAX_ORDER] __initdata; +static struct metadata_page_pair held_back[MAX_ORDER + 1] __initdata; /* * Eager metadata allocation. When the memblock allocator is freeing pages to @@ -211,8 +211,8 @@ static void kmsan_memblock_discard(void) * order=N-1, * - repeat. */ - collect.order = MAX_ORDER - 1; - for (int i = MAX_ORDER - 1; i >= 0; i--) { + collect.order = MAX_ORDER; + for (int i = MAX_ORDER; i >= 0; i--) { if (held_back[i].shadow) smallstack_push(&collect, held_back[i].shadow); if (held_back[i].origin) diff --git a/mm/memblock.c b/mm/memblock.c index 25fd0626a9e7..7911224b1ed3 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -2043,7 +2043,7 @@ static void __init __free_pages_memory(unsigned long start, unsigned long end) int order; while (start < end) { - order = min(MAX_ORDER - 1UL, __ffs(start)); + order = min_t(int, MAX_ORDER, __ffs(start)); while (start + (1UL << order) > end) order--; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index db3b270254f1..c8f0a8c2d049 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -596,7 +596,7 @@ static void online_pages_range(unsigned long start_pfn, unsigned long nr_pages) unsigned long pfn; /* - * Online the pages in MAX_ORDER - 1 aligned chunks. The callback might + * Online the pages in MAX_ORDER aligned chunks. The callback might * decide to not expose all pages to the buddy (e.g., expose them * later). We account all pages as being online and belonging to this * zone ("present"). @@ -605,7 +605,7 @@ static void online_pages_range(unsigned long start_pfn, unsigned long nr_pages) * this and the first chunk to online will be pageblock_nr_pages. */ for (pfn = start_pfn; pfn < end_pfn;) { - int order = min(MAX_ORDER - 1UL, __ffs(pfn)); + int order = min_t(int, MAX_ORDER, __ffs(pfn)); (*online_page_callback)(pfn_to_page(pfn), order); pfn += (1UL << order); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0936bde1d486..c3e49d028a7a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1063,7 +1063,7 @@ buddy_merge_likely(unsigned long pfn, unsigned long buddy_pfn, unsigned long higher_page_pfn; struct page *higher_page; - if (order >= MAX_ORDER - 2) + if (order >= MAX_ORDER - 1) return false; higher_page_pfn = buddy_pfn & pfn; @@ -1118,7 +1118,7 @@ static inline void __free_one_page(struct page *page, VM_BUG_ON_PAGE(pfn & ((1 << order) - 1), page); VM_BUG_ON_PAGE(bad_range(zone, page), page); - while (order < MAX_ORDER - 1) { + while (order < MAX_ORDER) { if (compaction_capture(capc, page, order, migratetype)) { __mod_zone_freepage_state(zone, -(1 << order), migratetype); @@ -2499,7 +2499,7 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, struct page *page; /* Find a page of the appropriate size in the preferred list */ - for (current_order = order; current_order < MAX_ORDER; ++current_order) { + for (current_order = order; current_order <= MAX_ORDER; ++current_order) { area = &(zone->free_area[current_order]); page = get_page_from_free_area(area, migratetype); if (!page) @@ -2871,7 +2871,7 @@ static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, continue; spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct free_area *area = &(zone->free_area[order]); page = get_page_from_free_area(area, MIGRATE_HIGHATOMIC); @@ -2955,7 +2955,7 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype, * approximates finding the pageblock with the most free pages, which * would be too costly to do exactly. */ - for (current_order = MAX_ORDER - 1; current_order >= min_order; + for (current_order = MAX_ORDER; current_order >= min_order; --current_order) { area = &(zone->free_area[current_order]); fallback_mt = find_suitable_fallback(area, current_order, @@ -2981,7 +2981,7 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype, return false; find_smallest: - for (current_order = order; current_order < MAX_ORDER; + for (current_order = order; current_order <= MAX_ORDER; current_order++) { area = &(zone->free_area[current_order]); fallback_mt = find_suitable_fallback(area, current_order, @@ -2994,7 +2994,7 @@ find_smallest: * This should not happen - we already found a suitable fallback * when looking for the largest page. */ - VM_BUG_ON(current_order == MAX_ORDER); + VM_BUG_ON(current_order > MAX_ORDER); do_steal: page = get_page_from_free_area(area, fallback_mt); @@ -3955,7 +3955,7 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, return true; /* For a high-order request, check at least one suitable page is free */ - for (o = order; o < MAX_ORDER; o++) { + for (o = order; o <= MAX_ORDER; o++) { struct free_area *area = &z->free_area[o]; int mt; @@ -5475,7 +5475,7 @@ struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid, * There are several places where we assume that the order value is sane * so bail out early if the request is out of bound. */ - if (WARN_ON_ONCE_GFP(order >= MAX_ORDER, gfp)) + if (WARN_ON_ONCE_GFP(order > MAX_ORDER, gfp)) return NULL; gfp &= gfp_allowed_mask; @@ -6205,8 +6205,8 @@ void __show_free_areas(unsigned int filter, nodemask_t *nodemask, int max_zone_i for_each_populated_zone(zone) { unsigned int order; - unsigned long nr[MAX_ORDER], flags, total = 0; - unsigned char types[MAX_ORDER]; + unsigned long nr[MAX_ORDER + 1], flags, total = 0; + unsigned char types[MAX_ORDER + 1]; if (zone_idx(zone) > max_zone_idx) continue; @@ -6216,7 +6216,7 @@ void __show_free_areas(unsigned int filter, nodemask_t *nodemask, int max_zone_i printk(KERN_CONT "%s: ", zone->name); spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct free_area *area = &zone->free_area[order]; int type; @@ -6230,7 +6230,7 @@ void __show_free_areas(unsigned int filter, nodemask_t *nodemask, int max_zone_i } } spin_unlock_irqrestore(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { printk(KERN_CONT "%lu*%lukB ", nr[order], K(1UL) << order); if (nr[order]) @@ -7581,7 +7581,7 @@ static inline void setup_usemap(struct zone *zone) {} /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ void __init set_pageblock_order(void) { - unsigned int order = MAX_ORDER - 1; + unsigned int order = MAX_ORDER; /* Check that pageblock_nr_pages has not already been setup */ if (pageblock_order) @@ -9076,7 +9076,7 @@ void *__init alloc_large_system_hash(const char *tablename, else table = memblock_alloc_raw(size, SMP_CACHE_BYTES); - } else if (get_order(size) >= MAX_ORDER || hashdist) { + } else if (get_order(size) > MAX_ORDER || hashdist) { table = vmalloc_huge(size, gfp_flags); virt = true; if (table) @@ -9290,7 +9290,7 @@ int alloc_contig_range(unsigned long start, unsigned long end, order = 0; outer_start = start; while (!PageBuddy(pfn_to_page(outer_start))) { - if (++order >= MAX_ORDER) { + if (++order > MAX_ORDER) { outer_start = start; break; } @@ -9540,7 +9540,7 @@ bool is_free_buddy_page(struct page *page) unsigned long pfn = page_to_pfn(page); unsigned int order; - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct page *page_head = page - (pfn & ((1 << order) - 1)); if (PageBuddy(page_head) && @@ -9548,7 +9548,7 @@ bool is_free_buddy_page(struct page *page) break; } - return order < MAX_ORDER; + return order <= MAX_ORDER; } EXPORT_SYMBOL(is_free_buddy_page); @@ -9599,7 +9599,7 @@ bool take_page_off_buddy(struct page *page) bool ret = false; spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct page *page_head = page - (pfn & ((1 << order) - 1)); int page_order = buddy_order(page_head); diff --git a/mm/page_isolation.c b/mm/page_isolation.c index 47fbc1696466..c6f3605e37ab 100644 --- a/mm/page_isolation.c +++ b/mm/page_isolation.c @@ -226,7 +226,7 @@ static void unset_migratetype_isolate(struct page *page, int migratetype) */ if (PageBuddy(page)) { order = buddy_order(page); - if (order >= pageblock_order && order < MAX_ORDER - 1) { + if (order >= pageblock_order && order < MAX_ORDER) { buddy = find_buddy_page_pfn(page, page_to_pfn(page), order, NULL); if (buddy && !is_migrate_isolate_page(buddy)) { @@ -290,11 +290,11 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages) * isolate_single_pageblock() * @migratetype: migrate type to set in error recovery. * - * Free and in-use pages can be as big as MAX_ORDER-1 and contain more than one + * Free and in-use pages can be as big as MAX_ORDER and contain more than one * pageblock. When not all pageblocks within a page are isolated at the same * time, free page accounting can go wrong. For example, in the case of - * MAX_ORDER-1 = pageblock_order + 1, a MAX_ORDER-1 page has two pagelbocks. - * [ MAX_ORDER-1 ] + * MAX_ORDER = pageblock_order + 1, a MAX_ORDER page has two pagelbocks. + * [ MAX_ORDER ] * [ pageblock0 | pageblock1 ] * When either pageblock is isolated, if it is a free page, the page is not * split into separate migratetype lists, which is supposed to; if it is an @@ -451,7 +451,7 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, int flags, * the free page to the right migratetype list. * * head_pfn is not used here as a hugetlb page order - * can be bigger than MAX_ORDER-1, but after it is + * can be bigger than MAX_ORDER, but after it is * freed, the free page order is not. Use pfn within * the range to find the head of the free page. */ @@ -459,7 +459,7 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, int flags, outer_pfn = pfn; while (!PageBuddy(pfn_to_page(outer_pfn))) { /* stop if we cannot find the free page */ - if (++order >= MAX_ORDER) + if (++order > MAX_ORDER) goto failed; outer_pfn &= ~0UL << order; } diff --git a/mm/page_owner.c b/mm/page_owner.c index 220cdeddc295..31169b3e7f06 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -315,7 +315,7 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m, unsigned long freepage_order; freepage_order = buddy_order_unsafe(page); - if (freepage_order < MAX_ORDER) + if (freepage_order <= MAX_ORDER) pfn += (1UL << freepage_order) - 1; continue; } @@ -549,7 +549,7 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) if (PageBuddy(page)) { unsigned long freepage_order = buddy_order_unsafe(page); - if (freepage_order < MAX_ORDER) + if (freepage_order <= MAX_ORDER) pfn += (1UL << freepage_order) - 1; continue; } @@ -657,7 +657,7 @@ static void init_pages_in_zone(pg_data_t *pgdat, struct zone *zone) if (PageBuddy(page)) { unsigned long order = buddy_order_unsafe(page); - if (order > 0 && order < MAX_ORDER) + if (order > 0 && order <= MAX_ORDER) pfn += (1UL << order) - 1; continue; } diff --git a/mm/page_reporting.c b/mm/page_reporting.c index 275b466de37b..b021f482a4cb 100644 --- a/mm/page_reporting.c +++ b/mm/page_reporting.c @@ -20,7 +20,7 @@ static int page_order_update_notify(const char *val, const struct kernel_param * * If param is set beyond this limit, order is set to default * pageblock_order value */ - return param_set_uint_minmax(val, kp, 0, MAX_ORDER-1); + return param_set_uint_minmax(val, kp, 0, MAX_ORDER); } static const struct kernel_param_ops page_reporting_param_ops = { @@ -276,7 +276,7 @@ page_reporting_process_zone(struct page_reporting_dev_info *prdev, return err; /* Process each free list starting from lowest order/mt */ - for (order = page_reporting_order; order < MAX_ORDER; order++) { + for (order = page_reporting_order; order <= MAX_ORDER; order++) { for (mt = 0; mt < MIGRATE_TYPES; mt++) { /* We do not pull pages from the isolate free list */ if (is_migrate_isolate(mt)) @@ -370,7 +370,7 @@ int page_reporting_register(struct page_reporting_dev_info *prdev) */ if (page_reporting_order == -1) { - if (prdev->order > 0 && prdev->order < MAX_ORDER) + if (prdev->order > 0 && prdev->order <= MAX_ORDER) page_reporting_order = prdev->order; else page_reporting_order = pageblock_order; diff --git a/mm/shuffle.h b/mm/shuffle.h index cec62984f7d3..a6bdf54f96f1 100644 --- a/mm/shuffle.h +++ b/mm/shuffle.h @@ -4,7 +4,7 @@ #define _MM_SHUFFLE_H #include -#define SHUFFLE_ORDER (MAX_ORDER-1) +#define SHUFFLE_ORDER MAX_ORDER #ifdef CONFIG_SHUFFLE_PAGE_ALLOCATOR DECLARE_STATIC_KEY_FALSE(page_alloc_shuffle_key); diff --git a/mm/slab.c b/mm/slab.c index edbe722fb906..6b7c172158e5 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -465,7 +465,7 @@ static int __init slab_max_order_setup(char *str) { get_option(&str, &slab_max_order); slab_max_order = slab_max_order < 0 ? 0 : - min(slab_max_order, MAX_ORDER - 1); + min(slab_max_order, MAX_ORDER); slab_max_order_set = true; return 1; diff --git a/mm/slub.c b/mm/slub.c index 32eb6b50fe18..f49d669ff604 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4171,8 +4171,8 @@ static inline int calculate_order(unsigned int size) /* * Doh this slab cannot be placed using slub_max_order. */ - order = calc_slab_order(size, 1, MAX_ORDER - 1, 1); - if (order < MAX_ORDER) + order = calc_slab_order(size, 1, MAX_ORDER, 1); + if (order <= MAX_ORDER) return order; return -ENOSYS; } @@ -4697,7 +4697,7 @@ __setup("slub_min_order=", setup_slub_min_order); static int __init setup_slub_max_order(char *str) { get_option(&str, (int *)&slub_max_order); - slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); + slub_max_order = min_t(unsigned int, slub_max_order, MAX_ORDER); return 1; } diff --git a/mm/vmscan.c b/mm/vmscan.c index 8faac4310cb5..98719e72b5e2 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -7002,7 +7002,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order, * scan_control uses s8 fields for order, priority, and reclaim_idx. * Confirm they are large enough for max values. */ - BUILD_BUG_ON(MAX_ORDER > S8_MAX); + BUILD_BUG_ON(MAX_ORDER >= S8_MAX); BUILD_BUG_ON(DEF_PRIORITY > S8_MAX); BUILD_BUG_ON(MAX_NR_ZONES > S8_MAX); diff --git a/mm/vmstat.c b/mm/vmstat.c index 1ea6a5ce1c41..b7307627772d 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1055,7 +1055,7 @@ static void fill_contig_page_info(struct zone *zone, info->free_blocks_total = 0; info->free_blocks_suitable = 0; - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { unsigned long blocks; /* @@ -1088,7 +1088,7 @@ static int __fragmentation_index(unsigned int order, struct contig_page_info *in { unsigned long requested = 1UL << order; - if (WARN_ON_ONCE(order >= MAX_ORDER)) + if (WARN_ON_ONCE(order > MAX_ORDER)) return 0; if (!info->free_blocks_total) @@ -1462,7 +1462,7 @@ static void frag_show_print(struct seq_file *m, pg_data_t *pgdat, int order; seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); - for (order = 0; order < MAX_ORDER; ++order) + for (order = 0; order <= MAX_ORDER; ++order) /* * Access to nr_free is lockless as nr_free is used only for * printing purposes. Use data_race to avoid KCSAN warning. @@ -1491,7 +1491,7 @@ static void pagetypeinfo_showfree_print(struct seq_file *m, pgdat->node_id, zone->name, migratetype_names[mtype]); - for (order = 0; order < MAX_ORDER; ++order) { + for (order = 0; order <= MAX_ORDER; ++order) { unsigned long freecount = 0; struct free_area *area; struct list_head *curr; @@ -1531,7 +1531,7 @@ static void pagetypeinfo_showfree(struct seq_file *m, void *arg) /* Print header */ seq_printf(m, "%-43s ", "Free pages count per migrate type at order"); - for (order = 0; order < MAX_ORDER; ++order) + for (order = 0; order <= MAX_ORDER; ++order) seq_printf(m, "%6d ", order); seq_putc(m, '\n'); @@ -2153,7 +2153,7 @@ static void unusable_show_print(struct seq_file *m, seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); - for (order = 0; order < MAX_ORDER; ++order) { + for (order = 0; order <= MAX_ORDER; ++order) { fill_contig_page_info(zone, order, &info); index = unusable_free_index(order, &info); seq_printf(m, "%d.%03d ", index / 1000, index % 1000); @@ -2205,7 +2205,7 @@ static void extfrag_show_print(struct seq_file *m, seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); - for (order = 0; order < MAX_ORDER; ++order) { + for (order = 0; order <= MAX_ORDER; ++order) { fill_contig_page_info(zone, order, &info); index = __fragmentation_index(order, &info); seq_printf(m, "%2d.%03d ", index / 1000, index % 1000); diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c index 854772dd52fd..9b66d6aeeb1a 100644 --- a/net/smc/smc_ib.c +++ b/net/smc/smc_ib.c @@ -843,7 +843,7 @@ long smc_ib_setup_per_ibdev(struct smc_ib_device *smcibdev) goto out; /* the calculated number of cq entries fits to mlx5 cq allocation */ cqe_size_order = cache_line_size() == 128 ? 7 : 6; - smc_order = MAX_ORDER - cqe_size_order - 1; + smc_order = MAX_ORDER - cqe_size_order; if (SMC_MAX_CQE + 2 > (0x00000001 << smc_order) * PAGE_SIZE) cqattr.cqe = (0x00000001 << smc_order) * PAGE_SIZE - 2; smcibdev->roce_cq_send = ib_create_cq(smcibdev->ibdev, diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 64499056648a..51ad29940f05 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -38,7 +38,7 @@ static int param_set_bufsize(const char *val, const struct kernel_param *kp) size = memparse(val, NULL); order = get_order(size); - if (order >= MAX_ORDER) + if (order > MAX_ORDER) return -EINVAL; ima_maxorder = order; ima_bufsize = PAGE_SIZE << order; diff --git a/tools/testing/memblock/linux/mmzone.h b/tools/testing/memblock/linux/mmzone.h index e65f89b12f1c..134f8eab0768 100644 --- a/tools/testing/memblock/linux/mmzone.h +++ b/tools/testing/memblock/linux/mmzone.h @@ -17,10 +17,10 @@ enum zone_type { }; #define MAX_NR_ZONES __MAX_NR_ZONES -#define MAX_ORDER 11 -#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1)) +#define MAX_ORDER 10 +#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER) -#define pageblock_order (MAX_ORDER - 1) +#define pageblock_order MAX_ORDER #define pageblock_nr_pages BIT(pageblock_order) #define pageblock_align(pfn) ALIGN((pfn), pageblock_nr_pages) #define pageblock_start_pfn(pfn) ALIGN_DOWN((pfn), pageblock_nr_pages) -- cgit v1.2.3 From a734991ccaec1985fff42fb26bb6d789d35defb4 Mon Sep 17 00:00:00 2001 From: Axel Rasmussen Date: Tue, 14 Mar 2023 15:12:47 -0700 Subject: mm: userfaultfd: rename functions for clarity + consistency Patch series "mm: userfaultfd: refactor and add UFFDIO_CONTINUE_MODE_WP", v5. - Commits 1-3 refactor userfaultfd ioctl code without behavior changes, with the main goal of improving consistency and reducing the number of function args. - Commit 4 adds UFFDIO_CONTINUE_MODE_WP. This patch (of 4): The basic problem is, over time we've added new userfaultfd ioctls, and we've refactored the code so functions which used to handle only one case are now re-used to deal with several cases. While this happened, we didn't bother to rename the functions. Similarly, as we added new functions, we cargo-culted pieces of the now-inconsistent naming scheme, so those functions too ended up with names that don't make a lot of sense. A key point here is, "copy" in most userfaultfd code refers specifically to UFFDIO_COPY, where we allocate a new page and copy its contents from userspace. There are many functions with "copy" in the name that don't actually do this (at least in some cases). So, rename things into a consistent scheme. The high level idea is that the call stack for userfaultfd ioctls becomes: userfaultfd_ioctl -> userfaultfd_(particular ioctl) -> mfill_atomic_(particular kind of fill operation) -> mfill_atomic /* loops over pages in range */ -> mfill_atomic_pte /* deals with single pages */ -> mfill_atomic_pte_(particular kind of fill operation) -> mfill_atomic_install_pte There are of course some special cases (shmem, hugetlb), but this is the general structure which all function names now adhere to. Link: https://lkml.kernel.org/r/20230314221250.682452-1-axelrasmussen@google.com Link: https://lkml.kernel.org/r/20230314221250.682452-2-axelrasmussen@google.com Signed-off-by: Axel Rasmussen Acked-by: Peter Xu Acked-by: Mike Rapoport (IBM) Cc: Al Viro Cc: Hugh Dickins Cc: James Houghton Cc: Jan Kara Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Mike Kravetz Cc: Muchun Song Cc: Nadav Amit Cc: Shuah Khan Signed-off-by: Andrew Morton --- fs/userfaultfd.c | 18 ++++---- include/linux/hugetlb.h | 30 ++++++------- include/linux/userfaultfd_k.h | 18 ++++---- mm/hugetlb.c | 20 ++++----- mm/userfaultfd.c | 98 +++++++++++++++++++++---------------------- 5 files changed, 92 insertions(+), 92 deletions(-) (limited to 'include') diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 881e9c82b9d1..4aedfd98e3f5 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1756,9 +1756,9 @@ static int userfaultfd_copy(struct userfaultfd_ctx *ctx, if (uffdio_copy.mode & ~(UFFDIO_COPY_MODE_DONTWAKE|UFFDIO_COPY_MODE_WP)) goto out; if (mmget_not_zero(ctx->mm)) { - ret = mcopy_atomic(ctx->mm, uffdio_copy.dst, uffdio_copy.src, - uffdio_copy.len, &ctx->mmap_changing, - uffdio_copy.mode); + ret = mfill_atomic_copy(ctx->mm, uffdio_copy.dst, uffdio_copy.src, + uffdio_copy.len, &ctx->mmap_changing, + uffdio_copy.mode); mmput(ctx->mm); } else { return -ESRCH; @@ -1808,9 +1808,9 @@ static int userfaultfd_zeropage(struct userfaultfd_ctx *ctx, goto out; if (mmget_not_zero(ctx->mm)) { - ret = mfill_zeropage(ctx->mm, uffdio_zeropage.range.start, - uffdio_zeropage.range.len, - &ctx->mmap_changing); + ret = mfill_atomic_zeropage(ctx->mm, uffdio_zeropage.range.start, + uffdio_zeropage.range.len, + &ctx->mmap_changing); mmput(ctx->mm); } else { return -ESRCH; @@ -1918,9 +1918,9 @@ static int userfaultfd_continue(struct userfaultfd_ctx *ctx, unsigned long arg) goto out; if (mmget_not_zero(ctx->mm)) { - ret = mcopy_continue(ctx->mm, uffdio_continue.range.start, - uffdio_continue.range.len, - &ctx->mmap_changing); + ret = mfill_atomic_continue(ctx->mm, uffdio_continue.range.start, + uffdio_continue.range.len, + &ctx->mmap_changing); mmput(ctx->mm); } else { return -ESRCH; diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 8fb7d91cd0b1..152434396c48 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -158,13 +158,13 @@ unsigned long hugetlb_total_pages(void); vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, unsigned int flags); #ifdef CONFIG_USERFAULTFD -int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, pte_t *dst_pte, - struct vm_area_struct *dst_vma, - unsigned long dst_addr, - unsigned long src_addr, - enum mcopy_atomic_mode mode, - struct page **pagep, - bool wp_copy); +int hugetlb_mfill_atomic_pte(struct mm_struct *dst_mm, pte_t *dst_pte, + struct vm_area_struct *dst_vma, + unsigned long dst_addr, + unsigned long src_addr, + enum mcopy_atomic_mode mode, + struct page **pagep, + bool wp_copy); #endif /* CONFIG_USERFAULTFD */ bool hugetlb_reserve_pages(struct inode *inode, long from, long to, struct vm_area_struct *vma, @@ -393,14 +393,14 @@ static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb, } #ifdef CONFIG_USERFAULTFD -static inline int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, - pte_t *dst_pte, - struct vm_area_struct *dst_vma, - unsigned long dst_addr, - unsigned long src_addr, - enum mcopy_atomic_mode mode, - struct page **pagep, - bool wp_copy) +static inline int hugetlb_mfill_atomic_pte(struct mm_struct *dst_mm, + pte_t *dst_pte, + struct vm_area_struct *dst_vma, + unsigned long dst_addr, + unsigned long src_addr, + enum mcopy_atomic_mode mode, + struct page **pagep, + bool wp_copy) { BUG(); return 0; diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 0cf8880219da..ac178d810dc7 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -61,15 +61,15 @@ extern int mfill_atomic_install_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, unsigned long dst_addr, struct page *page, bool newly_allocated, bool wp_copy); -extern ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start, - unsigned long src_start, unsigned long len, - atomic_t *mmap_changing, __u64 mode); -extern ssize_t mfill_zeropage(struct mm_struct *dst_mm, - unsigned long dst_start, - unsigned long len, - atomic_t *mmap_changing); -extern ssize_t mcopy_continue(struct mm_struct *dst_mm, unsigned long dst_start, - unsigned long len, atomic_t *mmap_changing); +extern ssize_t mfill_atomic_copy(struct mm_struct *dst_mm, unsigned long dst_start, + unsigned long src_start, unsigned long len, + atomic_t *mmap_changing, __u64 mode); +extern ssize_t mfill_atomic_zeropage(struct mm_struct *dst_mm, + unsigned long dst_start, + unsigned long len, + atomic_t *mmap_changing); +extern ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long dst_start, + unsigned long len, atomic_t *mmap_changing); extern int mwriteprotect_range(struct mm_struct *dst_mm, unsigned long start, unsigned long len, bool enable_wp, atomic_t *mmap_changing); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 9122e50ae02a..b1e474aa2fc5 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6156,17 +6156,17 @@ out_mutex: #ifdef CONFIG_USERFAULTFD /* - * Used by userfaultfd UFFDIO_COPY. Based on mcopy_atomic_pte with - * modifications for huge pages. + * Used by userfaultfd UFFDIO_* ioctls. Based on userfaultfd's mfill_atomic_pte + * with modifications for hugetlb pages. */ -int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, - pte_t *dst_pte, - struct vm_area_struct *dst_vma, - unsigned long dst_addr, - unsigned long src_addr, - enum mcopy_atomic_mode mode, - struct page **pagep, - bool wp_copy) +int hugetlb_mfill_atomic_pte(struct mm_struct *dst_mm, + pte_t *dst_pte, + struct vm_area_struct *dst_vma, + unsigned long dst_addr, + unsigned long src_addr, + enum mcopy_atomic_mode mode, + struct page **pagep, + bool wp_copy) { bool is_continue = (mode == MCOPY_ATOMIC_CONTINUE); struct hstate *h = hstate_vma(dst_vma); diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 23cabd02ac52..874379ce271f 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -127,13 +127,13 @@ out_unlock: return ret; } -static int mcopy_atomic_pte(struct mm_struct *dst_mm, - pmd_t *dst_pmd, - struct vm_area_struct *dst_vma, - unsigned long dst_addr, - unsigned long src_addr, - struct page **pagep, - bool wp_copy) +static int mfill_atomic_pte_copy(struct mm_struct *dst_mm, + pmd_t *dst_pmd, + struct vm_area_struct *dst_vma, + unsigned long dst_addr, + unsigned long src_addr, + struct page **pagep, + bool wp_copy) { void *page_kaddr; int ret; @@ -204,10 +204,10 @@ out_release: goto out; } -static int mfill_zeropage_pte(struct mm_struct *dst_mm, - pmd_t *dst_pmd, - struct vm_area_struct *dst_vma, - unsigned long dst_addr) +static int mfill_atomic_pte_zeropage(struct mm_struct *dst_mm, + pmd_t *dst_pmd, + struct vm_area_struct *dst_vma, + unsigned long dst_addr) { pte_t _dst_pte, *dst_pte; spinlock_t *ptl; @@ -240,11 +240,11 @@ out_unlock: } /* Handles UFFDIO_CONTINUE for all shmem VMAs (shared or private). */ -static int mcontinue_atomic_pte(struct mm_struct *dst_mm, - pmd_t *dst_pmd, - struct vm_area_struct *dst_vma, - unsigned long dst_addr, - bool wp_copy) +static int mfill_atomic_pte_continue(struct mm_struct *dst_mm, + pmd_t *dst_pmd, + struct vm_area_struct *dst_vma, + unsigned long dst_addr, + bool wp_copy) { struct inode *inode = file_inode(dst_vma->vm_file); pgoff_t pgoff = linear_page_index(dst_vma, dst_addr); @@ -307,10 +307,10 @@ static pmd_t *mm_alloc_pmd(struct mm_struct *mm, unsigned long address) #ifdef CONFIG_HUGETLB_PAGE /* - * __mcopy_atomic processing for HUGETLB vmas. Note that this routine is + * mfill_atomic processing for HUGETLB vmas. Note that this routine is * called with mmap_lock held, it will release mmap_lock before returning. */ -static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, +static __always_inline ssize_t mfill_atomic_hugetlb(struct mm_struct *dst_mm, struct vm_area_struct *dst_vma, unsigned long dst_start, unsigned long src_start, @@ -411,7 +411,7 @@ retry: goto out_unlock; } - err = hugetlb_mcopy_atomic_pte(dst_mm, dst_pte, dst_vma, + err = hugetlb_mfill_atomic_pte(dst_mm, dst_pte, dst_vma, dst_addr, src_addr, mode, &page, wp_copy); @@ -463,7 +463,7 @@ out: } #else /* !CONFIG_HUGETLB_PAGE */ /* fail at build time if gcc attempts to use this */ -extern ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, +extern ssize_t mfill_atomic_hugetlb(struct mm_struct *dst_mm, struct vm_area_struct *dst_vma, unsigned long dst_start, unsigned long src_start, @@ -484,8 +484,8 @@ static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm, ssize_t err; if (mode == MCOPY_ATOMIC_CONTINUE) { - return mcontinue_atomic_pte(dst_mm, dst_pmd, dst_vma, dst_addr, - wp_copy); + return mfill_atomic_pte_continue(dst_mm, dst_pmd, dst_vma, + dst_addr, wp_copy); } /* @@ -500,11 +500,11 @@ static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm, */ if (!(dst_vma->vm_flags & VM_SHARED)) { if (mode == MCOPY_ATOMIC_NORMAL) - err = mcopy_atomic_pte(dst_mm, dst_pmd, dst_vma, - dst_addr, src_addr, page, - wp_copy); + err = mfill_atomic_pte_copy(dst_mm, dst_pmd, dst_vma, + dst_addr, src_addr, page, + wp_copy); else - err = mfill_zeropage_pte(dst_mm, dst_pmd, + err = mfill_atomic_pte_zeropage(dst_mm, dst_pmd, dst_vma, dst_addr); } else { err = shmem_mfill_atomic_pte(dst_mm, dst_pmd, dst_vma, @@ -516,13 +516,13 @@ static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm, return err; } -static __always_inline ssize_t __mcopy_atomic(struct mm_struct *dst_mm, - unsigned long dst_start, - unsigned long src_start, - unsigned long len, - enum mcopy_atomic_mode mcopy_mode, - atomic_t *mmap_changing, - __u64 mode) +static __always_inline ssize_t mfill_atomic(struct mm_struct *dst_mm, + unsigned long dst_start, + unsigned long src_start, + unsigned long len, + enum mcopy_atomic_mode mcopy_mode, + atomic_t *mmap_changing, + __u64 mode) { struct vm_area_struct *dst_vma; ssize_t err; @@ -588,9 +588,9 @@ retry: * If this is a HUGETLB vma, pass off to appropriate routine */ if (is_vm_hugetlb_page(dst_vma)) - return __mcopy_atomic_hugetlb(dst_mm, dst_vma, dst_start, - src_start, len, mcopy_mode, - wp_copy); + return mfill_atomic_hugetlb(dst_mm, dst_vma, dst_start, + src_start, len, mcopy_mode, + wp_copy); if (!vma_is_anonymous(dst_vma) && !vma_is_shmem(dst_vma)) goto out_unlock; @@ -688,26 +688,26 @@ out: return copied ? copied : err; } -ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start, - unsigned long src_start, unsigned long len, - atomic_t *mmap_changing, __u64 mode) +ssize_t mfill_atomic_copy(struct mm_struct *dst_mm, unsigned long dst_start, + unsigned long src_start, unsigned long len, + atomic_t *mmap_changing, __u64 mode) { - return __mcopy_atomic(dst_mm, dst_start, src_start, len, - MCOPY_ATOMIC_NORMAL, mmap_changing, mode); + return mfill_atomic(dst_mm, dst_start, src_start, len, + MCOPY_ATOMIC_NORMAL, mmap_changing, mode); } -ssize_t mfill_zeropage(struct mm_struct *dst_mm, unsigned long start, - unsigned long len, atomic_t *mmap_changing) +ssize_t mfill_atomic_zeropage(struct mm_struct *dst_mm, unsigned long start, + unsigned long len, atomic_t *mmap_changing) { - return __mcopy_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_ZEROPAGE, - mmap_changing, 0); + return mfill_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_ZEROPAGE, + mmap_changing, 0); } -ssize_t mcopy_continue(struct mm_struct *dst_mm, unsigned long start, - unsigned long len, atomic_t *mmap_changing) +ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long start, + unsigned long len, atomic_t *mmap_changing) { - return __mcopy_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_CONTINUE, - mmap_changing, 0); + return mfill_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_CONTINUE, + mmap_changing, 0); } long uffd_wp_range(struct mm_struct *dst_mm, struct vm_area_struct *dst_vma, -- cgit v1.2.3 From 61c5004022f56c443b86800e8985d8803f3a22aa Mon Sep 17 00:00:00 2001 From: Axel Rasmussen Date: Tue, 14 Mar 2023 15:12:48 -0700 Subject: mm: userfaultfd: don't pass around both mm and vma Quite a few userfaultfd functions took both mm and vma pointers as arguments. Since the mm is trivially accessible via vma->vm_mm, there's no reason to pass both; it just needlessly extends the already long argument list. Get rid of the mm pointer, where possible, to shorten the argument list. Link: https://lkml.kernel.org/r/20230314221250.682452-3-axelrasmussen@google.com Signed-off-by: Axel Rasmussen Acked-by: Peter Xu Acked-by: Mike Rapoport (IBM) Cc: Al Viro Cc: Hugh Dickins Cc: James Houghton Cc: Jan Kara Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Mike Kravetz Cc: Muchun Song Cc: Nadav Amit Cc: Shuah Khan Signed-off-by: Andrew Morton --- fs/userfaultfd.c | 2 +- include/linux/hugetlb.h | 5 ++-- include/linux/shmem_fs.h | 4 +-- include/linux/userfaultfd_k.h | 4 +-- mm/hugetlb.c | 4 +-- mm/shmem.c | 7 +++-- mm/userfaultfd.c | 61 ++++++++++++++++++++----------------------- 7 files changed, 41 insertions(+), 46 deletions(-) (limited to 'include') diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 4aedfd98e3f5..d8d432ca81e6 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1644,7 +1644,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx, /* Reset ptes for the whole vma range if wr-protected */ if (userfaultfd_wp(vma)) - uffd_wp_range(mm, vma, start, vma_end - start, false); + uffd_wp_range(vma, start, vma_end - start, false); new_flags = vma->vm_flags & ~__VM_UFFD_FLAGS; prev = vma_merge(&vmi, mm, prev, start, vma_end, new_flags, diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 152434396c48..3cb7cd853fa8 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -158,7 +158,7 @@ unsigned long hugetlb_total_pages(void); vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, unsigned int flags); #ifdef CONFIG_USERFAULTFD -int hugetlb_mfill_atomic_pte(struct mm_struct *dst_mm, pte_t *dst_pte, +int hugetlb_mfill_atomic_pte(pte_t *dst_pte, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, @@ -393,8 +393,7 @@ static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb, } #ifdef CONFIG_USERFAULTFD -static inline int hugetlb_mfill_atomic_pte(struct mm_struct *dst_mm, - pte_t *dst_pte, +static inline int hugetlb_mfill_atomic_pte(pte_t *dst_pte, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index 50bf82b36995..922a2b45fe6f 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -152,14 +152,14 @@ extern void shmem_uncharge(struct inode *inode, long pages); #ifdef CONFIG_USERFAULTFD #ifdef CONFIG_SHMEM -extern int shmem_mfill_atomic_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, +extern int shmem_mfill_atomic_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, bool zeropage, bool wp_copy, struct page **pagep); #else /* !CONFIG_SHMEM */ -#define shmem_mfill_atomic_pte(dst_mm, dst_pmd, dst_vma, dst_addr, \ +#define shmem_mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, \ src_addr, zeropage, wp_copy, pagep) ({ BUG(); 0; }) #endif /* CONFIG_SHMEM */ #endif /* CONFIG_USERFAULTFD */ diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index ac178d810dc7..9458cd94a508 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -56,7 +56,7 @@ enum mcopy_atomic_mode { MCOPY_ATOMIC_CONTINUE, }; -extern int mfill_atomic_install_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, +extern int mfill_atomic_install_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, struct page *page, bool newly_allocated, bool wp_copy); @@ -73,7 +73,7 @@ extern ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long dst extern int mwriteprotect_range(struct mm_struct *dst_mm, unsigned long start, unsigned long len, bool enable_wp, atomic_t *mmap_changing); -extern long uffd_wp_range(struct mm_struct *dst_mm, struct vm_area_struct *vma, +extern long uffd_wp_range(struct vm_area_struct *vma, unsigned long start, unsigned long len, bool enable_wp); /* mm helpers */ diff --git a/mm/hugetlb.c b/mm/hugetlb.c index b1e474aa2fc5..6dc32cccbd9b 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6159,8 +6159,7 @@ out_mutex: * Used by userfaultfd UFFDIO_* ioctls. Based on userfaultfd's mfill_atomic_pte * with modifications for hugetlb pages. */ -int hugetlb_mfill_atomic_pte(struct mm_struct *dst_mm, - pte_t *dst_pte, +int hugetlb_mfill_atomic_pte(pte_t *dst_pte, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, @@ -6168,6 +6167,7 @@ int hugetlb_mfill_atomic_pte(struct mm_struct *dst_mm, struct page **pagep, bool wp_copy) { + struct mm_struct *dst_mm = dst_vma->vm_mm; bool is_continue = (mode == MCOPY_ATOMIC_CONTINUE); struct hstate *h = hstate_vma(dst_vma); struct address_space *mapping = dst_vma->vm_file->f_mapping; diff --git a/mm/shmem.c b/mm/shmem.c index fa6e38f2f55f..9d13b9a64144 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2429,8 +2429,7 @@ static struct inode *shmem_get_inode(struct mnt_idmap *idmap, struct super_block } #ifdef CONFIG_USERFAULTFD -int shmem_mfill_atomic_pte(struct mm_struct *dst_mm, - pmd_t *dst_pmd, +int shmem_mfill_atomic_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, @@ -2520,11 +2519,11 @@ int shmem_mfill_atomic_pte(struct mm_struct *dst_mm, goto out_release; ret = shmem_add_to_page_cache(folio, mapping, pgoff, NULL, - gfp & GFP_RECLAIM_MASK, dst_mm); + gfp & GFP_RECLAIM_MASK, dst_vma->vm_mm); if (ret) goto out_release; - ret = mfill_atomic_install_pte(dst_mm, dst_pmd, dst_vma, dst_addr, + ret = mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, &folio->page, true, wp_copy); if (ret) goto out_delete_from_cache; diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 874379ce271f..c3cc6cb04548 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -55,12 +55,13 @@ struct vm_area_struct *find_dst_vma(struct mm_struct *dst_mm, * This function handles both MCOPY_ATOMIC_NORMAL and _CONTINUE for both shmem * and anon, and for both shared and private VMAs. */ -int mfill_atomic_install_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, +int mfill_atomic_install_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, struct page *page, bool newly_allocated, bool wp_copy) { int ret; + struct mm_struct *dst_mm = dst_vma->vm_mm; pte_t _dst_pte, *dst_pte; bool writable = dst_vma->vm_flags & VM_WRITE; bool vm_shared = dst_vma->vm_flags & VM_SHARED; @@ -127,8 +128,7 @@ out_unlock: return ret; } -static int mfill_atomic_pte_copy(struct mm_struct *dst_mm, - pmd_t *dst_pmd, +static int mfill_atomic_pte_copy(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, @@ -190,10 +190,10 @@ static int mfill_atomic_pte_copy(struct mm_struct *dst_mm, __SetPageUptodate(page); ret = -ENOMEM; - if (mem_cgroup_charge(page_folio(page), dst_mm, GFP_KERNEL)) + if (mem_cgroup_charge(page_folio(page), dst_vma->vm_mm, GFP_KERNEL)) goto out_release; - ret = mfill_atomic_install_pte(dst_mm, dst_pmd, dst_vma, dst_addr, + ret = mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, page, true, wp_copy); if (ret) goto out_release; @@ -204,8 +204,7 @@ out_release: goto out; } -static int mfill_atomic_pte_zeropage(struct mm_struct *dst_mm, - pmd_t *dst_pmd, +static int mfill_atomic_pte_zeropage(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr) { @@ -217,7 +216,7 @@ static int mfill_atomic_pte_zeropage(struct mm_struct *dst_mm, _dst_pte = pte_mkspecial(pfn_pte(my_zero_pfn(dst_addr), dst_vma->vm_page_prot)); - dst_pte = pte_offset_map_lock(dst_mm, dst_pmd, dst_addr, &ptl); + dst_pte = pte_offset_map_lock(dst_vma->vm_mm, dst_pmd, dst_addr, &ptl); if (dst_vma->vm_file) { /* the shmem MAP_PRIVATE case requires checking the i_size */ inode = dst_vma->vm_file->f_inode; @@ -230,7 +229,7 @@ static int mfill_atomic_pte_zeropage(struct mm_struct *dst_mm, ret = -EEXIST; if (!pte_none(*dst_pte)) goto out_unlock; - set_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte); + set_pte_at(dst_vma->vm_mm, dst_addr, dst_pte, _dst_pte); /* No need to invalidate - it was non-present before */ update_mmu_cache(dst_vma, dst_addr, dst_pte); ret = 0; @@ -240,8 +239,7 @@ out_unlock: } /* Handles UFFDIO_CONTINUE for all shmem VMAs (shared or private). */ -static int mfill_atomic_pte_continue(struct mm_struct *dst_mm, - pmd_t *dst_pmd, +static int mfill_atomic_pte_continue(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, bool wp_copy) @@ -269,7 +267,7 @@ static int mfill_atomic_pte_continue(struct mm_struct *dst_mm, goto out_release; } - ret = mfill_atomic_install_pte(dst_mm, dst_pmd, dst_vma, dst_addr, + ret = mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, page, false, wp_copy); if (ret) goto out_release; @@ -310,7 +308,7 @@ static pmd_t *mm_alloc_pmd(struct mm_struct *mm, unsigned long address) * mfill_atomic processing for HUGETLB vmas. Note that this routine is * called with mmap_lock held, it will release mmap_lock before returning. */ -static __always_inline ssize_t mfill_atomic_hugetlb(struct mm_struct *dst_mm, +static __always_inline ssize_t mfill_atomic_hugetlb( struct vm_area_struct *dst_vma, unsigned long dst_start, unsigned long src_start, @@ -318,6 +316,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb(struct mm_struct *dst_mm, enum mcopy_atomic_mode mode, bool wp_copy) { + struct mm_struct *dst_mm = dst_vma->vm_mm; int vm_shared = dst_vma->vm_flags & VM_SHARED; ssize_t err; pte_t *dst_pte; @@ -411,7 +410,7 @@ retry: goto out_unlock; } - err = hugetlb_mfill_atomic_pte(dst_mm, dst_pte, dst_vma, + err = hugetlb_mfill_atomic_pte(dst_pte, dst_vma, dst_addr, src_addr, mode, &page, wp_copy); @@ -463,17 +462,15 @@ out: } #else /* !CONFIG_HUGETLB_PAGE */ /* fail at build time if gcc attempts to use this */ -extern ssize_t mfill_atomic_hugetlb(struct mm_struct *dst_mm, - struct vm_area_struct *dst_vma, - unsigned long dst_start, - unsigned long src_start, - unsigned long len, - enum mcopy_atomic_mode mode, - bool wp_copy); +extern ssize_t mfill_atomic_hugetlb(struct vm_area_struct *dst_vma, + unsigned long dst_start, + unsigned long src_start, + unsigned long len, + enum mcopy_atomic_mode mode, + bool wp_copy); #endif /* CONFIG_HUGETLB_PAGE */ -static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm, - pmd_t *dst_pmd, +static __always_inline ssize_t mfill_atomic_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, @@ -484,7 +481,7 @@ static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm, ssize_t err; if (mode == MCOPY_ATOMIC_CONTINUE) { - return mfill_atomic_pte_continue(dst_mm, dst_pmd, dst_vma, + return mfill_atomic_pte_continue(dst_pmd, dst_vma, dst_addr, wp_copy); } @@ -500,14 +497,14 @@ static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm, */ if (!(dst_vma->vm_flags & VM_SHARED)) { if (mode == MCOPY_ATOMIC_NORMAL) - err = mfill_atomic_pte_copy(dst_mm, dst_pmd, dst_vma, + err = mfill_atomic_pte_copy(dst_pmd, dst_vma, dst_addr, src_addr, page, wp_copy); else - err = mfill_atomic_pte_zeropage(dst_mm, dst_pmd, + err = mfill_atomic_pte_zeropage(dst_pmd, dst_vma, dst_addr); } else { - err = shmem_mfill_atomic_pte(dst_mm, dst_pmd, dst_vma, + err = shmem_mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, src_addr, mode != MCOPY_ATOMIC_NORMAL, wp_copy, page); @@ -588,7 +585,7 @@ retry: * If this is a HUGETLB vma, pass off to appropriate routine */ if (is_vm_hugetlb_page(dst_vma)) - return mfill_atomic_hugetlb(dst_mm, dst_vma, dst_start, + return mfill_atomic_hugetlb(dst_vma, dst_start, src_start, len, mcopy_mode, wp_copy); @@ -641,7 +638,7 @@ retry: BUG_ON(pmd_none(*dst_pmd)); BUG_ON(pmd_trans_huge(*dst_pmd)); - err = mfill_atomic_pte(dst_mm, dst_pmd, dst_vma, dst_addr, + err = mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, src_addr, &page, mcopy_mode, wp_copy); cond_resched(); @@ -710,7 +707,7 @@ ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long start, mmap_changing, 0); } -long uffd_wp_range(struct mm_struct *dst_mm, struct vm_area_struct *dst_vma, +long uffd_wp_range(struct vm_area_struct *dst_vma, unsigned long start, unsigned long len, bool enable_wp) { unsigned int mm_cp_flags; @@ -732,7 +729,7 @@ long uffd_wp_range(struct mm_struct *dst_mm, struct vm_area_struct *dst_vma, */ if (!enable_wp && vma_wants_manual_pte_write_upgrade(dst_vma)) mm_cp_flags |= MM_CP_TRY_CHANGE_WRITABLE; - tlb_gather_mmu(&tlb, dst_mm); + tlb_gather_mmu(&tlb, dst_vma->vm_mm); ret = change_protection(&tlb, dst_vma, start, start + len, mm_cp_flags); tlb_finish_mmu(&tlb); @@ -788,7 +785,7 @@ int mwriteprotect_range(struct mm_struct *dst_mm, unsigned long start, _start = max(dst_vma->vm_start, start); _end = min(dst_vma->vm_end, end); - err = uffd_wp_range(dst_mm, dst_vma, _start, _end - _start, enable_wp); + err = uffd_wp_range(dst_vma, _start, _end - _start, enable_wp); /* Return 0 on success, <0 on failures */ if (err < 0) -- cgit v1.2.3 From d9712937037e0ce887920f321429826e9dbfd960 Mon Sep 17 00:00:00 2001 From: Axel Rasmussen Date: Tue, 14 Mar 2023 15:12:49 -0700 Subject: mm: userfaultfd: combine 'mode' and 'wp_copy' arguments Many userfaultfd ioctl functions take both a 'mode' and a 'wp_copy' argument. In future commits we plan to plumb the flags through to more places, so we'd be proliferating the very long argument list even further. Let's take the time to simplify the argument list. Combine the two arguments into one - and generalize, so when we add more flags in the future, it doesn't imply more function arguments. Since the modes (copy, zeropage, continue) are mutually exclusive, store them as an integer value (0, 1, 2) in the low bits. Place combine-able flag bits in the high bits. This is quite similar to an earlier patch proposed by Nadav Amit ("userfaultfd: introduce uffd_flags" [1]). The main difference is that patch only handled flags, whereas this patch *also* combines the "mode" argument into the same type to shorten the argument list. [1]: https://lore.kernel.org/all/20220619233449.181323-2-namit@vmware.com/ Link: https://lkml.kernel.org/r/20230314221250.682452-4-axelrasmussen@google.com Signed-off-by: Axel Rasmussen Acked-by: James Houghton Acked-by: Peter Xu Acked-by: Mike Rapoport (IBM) Cc: Al Viro Cc: Hugh Dickins Cc: Jan Kara Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Mike Kravetz Cc: Muchun Song Cc: Shuah Khan Signed-off-by: Andrew Morton --- fs/userfaultfd.c | 5 ++- include/linux/hugetlb.h | 10 +++--- include/linux/shmem_fs.h | 5 +-- include/linux/userfaultfd_k.h | 46 +++++++++++++++++--------- mm/hugetlb.c | 12 +++---- mm/shmem.c | 7 ++-- mm/userfaultfd.c | 76 +++++++++++++++++++------------------------ 7 files changed, 84 insertions(+), 77 deletions(-) (limited to 'include') diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index d8d432ca81e6..8971c3613cc6 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1729,6 +1729,7 @@ static int userfaultfd_copy(struct userfaultfd_ctx *ctx, struct uffdio_copy uffdio_copy; struct uffdio_copy __user *user_uffdio_copy; struct userfaultfd_wake_range range; + uffd_flags_t flags = 0; user_uffdio_copy = (struct uffdio_copy __user *) arg; @@ -1755,10 +1756,12 @@ static int userfaultfd_copy(struct userfaultfd_ctx *ctx, goto out; if (uffdio_copy.mode & ~(UFFDIO_COPY_MODE_DONTWAKE|UFFDIO_COPY_MODE_WP)) goto out; + if (uffdio_copy.mode & UFFDIO_COPY_MODE_WP) + flags |= MFILL_ATOMIC_WP; if (mmget_not_zero(ctx->mm)) { ret = mfill_atomic_copy(ctx->mm, uffdio_copy.dst, uffdio_copy.src, uffdio_copy.len, &ctx->mmap_changing, - uffdio_copy.mode); + flags); mmput(ctx->mm); } else { return -ESRCH; diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 3cb7cd853fa8..2a758bcd6719 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -162,9 +162,8 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, - enum mcopy_atomic_mode mode, - struct page **pagep, - bool wp_copy); + uffd_flags_t flags, + struct page **pagep); #endif /* CONFIG_USERFAULTFD */ bool hugetlb_reserve_pages(struct inode *inode, long from, long to, struct vm_area_struct *vma, @@ -397,9 +396,8 @@ static inline int hugetlb_mfill_atomic_pte(pte_t *dst_pte, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, - enum mcopy_atomic_mode mode, - struct page **pagep, - bool wp_copy) + uffd_flags_t flags, + struct page **pagep) { BUG(); return 0; diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index 922a2b45fe6f..3bb8d21edbb3 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -9,6 +9,7 @@ #include #include #include +#include /* inode in-kernel data */ @@ -156,11 +157,11 @@ extern int shmem_mfill_atomic_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, - bool zeropage, bool wp_copy, + uffd_flags_t flags, struct page **pagep); #else /* !CONFIG_SHMEM */ #define shmem_mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, \ - src_addr, zeropage, wp_copy, pagep) ({ BUG(); 0; }) + src_addr, flags, pagep) ({ BUG(); 0; }) #endif /* CONFIG_SHMEM */ #endif /* CONFIG_USERFAULTFD */ diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 9458cd94a508..4c477dece540 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -40,30 +40,44 @@ extern int sysctl_unprivileged_userfaultfd; extern vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason); -/* - * The mode of operation for __mcopy_atomic and its helpers. - * - * This is almost an implementation detail (mcopy_atomic below doesn't take this - * as a parameter), but it's exposed here because memory-kind-specific - * implementations (e.g. hugetlbfs) need to know the mode of operation. - */ -enum mcopy_atomic_mode { - /* A normal copy_from_user into the destination range. */ - MCOPY_ATOMIC_NORMAL, - /* Don't copy; map the destination range to the zero page. */ - MCOPY_ATOMIC_ZEROPAGE, - /* Just install pte(s) with the existing page(s) in the page cache. */ - MCOPY_ATOMIC_CONTINUE, +/* A combined operation mode + behavior flags. */ +typedef unsigned int __bitwise uffd_flags_t; + +/* Mutually exclusive modes of operation. */ +enum mfill_atomic_mode { + MFILL_ATOMIC_COPY, + MFILL_ATOMIC_ZEROPAGE, + MFILL_ATOMIC_CONTINUE, + NR_MFILL_ATOMIC_MODES, }; +#define MFILL_ATOMIC_MODE_BITS (const_ilog2(NR_MFILL_ATOMIC_MODES - 1) + 1) +#define MFILL_ATOMIC_BIT(nr) BIT(MFILL_ATOMIC_MODE_BITS + (nr)) +#define MFILL_ATOMIC_FLAG(nr) ((__force uffd_flags_t) MFILL_ATOMIC_BIT(nr)) +#define MFILL_ATOMIC_MODE_MASK ((__force uffd_flags_t) (MFILL_ATOMIC_BIT(0) - 1)) + +static inline bool uffd_flags_mode_is(uffd_flags_t flags, enum mfill_atomic_mode expected) +{ + return (flags & MFILL_ATOMIC_MODE_MASK) == ((__force uffd_flags_t) expected); +} + +static inline uffd_flags_t uffd_flags_set_mode(uffd_flags_t flags, enum mfill_atomic_mode mode) +{ + flags &= ~MFILL_ATOMIC_MODE_MASK; + return flags | ((__force uffd_flags_t) mode); +} + +/* Flags controlling behavior. These behavior changes are mode-independent. */ +#define MFILL_ATOMIC_WP MFILL_ATOMIC_FLAG(0) + extern int mfill_atomic_install_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, struct page *page, - bool newly_allocated, bool wp_copy); + bool newly_allocated, uffd_flags_t flags); extern ssize_t mfill_atomic_copy(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long src_start, unsigned long len, - atomic_t *mmap_changing, __u64 mode); + atomic_t *mmap_changing, uffd_flags_t flags); extern ssize_t mfill_atomic_zeropage(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long len, diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 6dc32cccbd9b..8bfd07f4c143 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6163,12 +6163,12 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, - enum mcopy_atomic_mode mode, - struct page **pagep, - bool wp_copy) + uffd_flags_t flags, + struct page **pagep) { struct mm_struct *dst_mm = dst_vma->vm_mm; - bool is_continue = (mode == MCOPY_ATOMIC_CONTINUE); + bool is_continue = uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE); + bool wp_enabled = (flags & MFILL_ATOMIC_WP); struct hstate *h = hstate_vma(dst_vma); struct address_space *mapping = dst_vma->vm_file->f_mapping; pgoff_t idx = vma_hugecache_offset(h, dst_vma, dst_addr); @@ -6303,7 +6303,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, * For either: (1) CONTINUE on a non-shared VMA, or (2) UFFDIO_COPY * with wp flag set, don't set pte write bit. */ - if (wp_copy || (is_continue && !vm_shared)) + if (wp_enabled || (is_continue && !vm_shared)) writable = 0; else writable = dst_vma->vm_flags & VM_WRITE; @@ -6318,7 +6318,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, _dst_pte = huge_pte_mkdirty(_dst_pte); _dst_pte = pte_mkyoung(_dst_pte); - if (wp_copy) + if (wp_enabled) _dst_pte = huge_pte_mkuffd_wp(_dst_pte); set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte); diff --git a/mm/shmem.c b/mm/shmem.c index 9d13b9a64144..b185c1db3009 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -76,7 +76,6 @@ static struct vfsmount *shm_mnt; #include #include #include -#include #include #include @@ -2433,7 +2432,7 @@ int shmem_mfill_atomic_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, - bool zeropage, bool wp_copy, + uffd_flags_t flags, struct page **pagep) { struct inode *inode = file_inode(dst_vma->vm_file); @@ -2465,7 +2464,7 @@ int shmem_mfill_atomic_pte(pmd_t *dst_pmd, if (!folio) goto out_unacct_blocks; - if (!zeropage) { /* COPY */ + if (uffd_flags_mode_is(flags, MFILL_ATOMIC_COPY)) { page_kaddr = kmap_local_folio(folio, 0); /* * The read mmap_lock is held here. Despite the @@ -2524,7 +2523,7 @@ int shmem_mfill_atomic_pte(pmd_t *dst_pmd, goto out_release; ret = mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, - &folio->page, true, wp_copy); + &folio->page, true, flags); if (ret) goto out_delete_from_cache; diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index c3cc6cb04548..a9b19b39413d 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -58,7 +58,7 @@ struct vm_area_struct *find_dst_vma(struct mm_struct *dst_mm, int mfill_atomic_install_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, struct page *page, - bool newly_allocated, bool wp_copy) + bool newly_allocated, uffd_flags_t flags) { int ret; struct mm_struct *dst_mm = dst_vma->vm_mm; @@ -77,7 +77,7 @@ int mfill_atomic_install_pte(pmd_t *dst_pmd, writable = false; if (writable) _dst_pte = pte_mkwrite(_dst_pte); - if (wp_copy) + if (flags & MFILL_ATOMIC_WP) _dst_pte = pte_mkuffd_wp(_dst_pte); dst_pte = pte_offset_map_lock(dst_mm, dst_pmd, dst_addr, &ptl); @@ -132,8 +132,8 @@ static int mfill_atomic_pte_copy(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, - struct page **pagep, - bool wp_copy) + uffd_flags_t flags, + struct page **pagep) { void *page_kaddr; int ret; @@ -194,7 +194,7 @@ static int mfill_atomic_pte_copy(pmd_t *dst_pmd, goto out_release; ret = mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, - page, true, wp_copy); + page, true, flags); if (ret) goto out_release; out: @@ -242,7 +242,7 @@ out_unlock: static int mfill_atomic_pte_continue(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, - bool wp_copy) + uffd_flags_t flags) { struct inode *inode = file_inode(dst_vma->vm_file); pgoff_t pgoff = linear_page_index(dst_vma, dst_addr); @@ -268,7 +268,7 @@ static int mfill_atomic_pte_continue(pmd_t *dst_pmd, } ret = mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, - page, false, wp_copy); + page, false, flags); if (ret) goto out_release; @@ -313,8 +313,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb( unsigned long dst_start, unsigned long src_start, unsigned long len, - enum mcopy_atomic_mode mode, - bool wp_copy) + uffd_flags_t flags) { struct mm_struct *dst_mm = dst_vma->vm_mm; int vm_shared = dst_vma->vm_flags & VM_SHARED; @@ -334,7 +333,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb( * by THP. Since we can not reliably insert a zero page, this * feature is not supported. */ - if (mode == MCOPY_ATOMIC_ZEROPAGE) { + if (uffd_flags_mode_is(flags, MFILL_ATOMIC_ZEROPAGE)) { mmap_read_unlock(dst_mm); return -EINVAL; } @@ -402,7 +401,7 @@ retry: goto out_unlock; } - if (mode != MCOPY_ATOMIC_CONTINUE && + if (!uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE) && !huge_pte_none_mostly(huge_ptep_get(dst_pte))) { err = -EEXIST; hugetlb_vma_unlock_read(dst_vma); @@ -410,9 +409,8 @@ retry: goto out_unlock; } - err = hugetlb_mfill_atomic_pte(dst_pte, dst_vma, - dst_addr, src_addr, mode, &page, - wp_copy); + err = hugetlb_mfill_atomic_pte(dst_pte, dst_vma, dst_addr, + src_addr, flags, &page); hugetlb_vma_unlock_read(dst_vma); mutex_unlock(&hugetlb_fault_mutex_table[hash]); @@ -466,23 +464,21 @@ extern ssize_t mfill_atomic_hugetlb(struct vm_area_struct *dst_vma, unsigned long dst_start, unsigned long src_start, unsigned long len, - enum mcopy_atomic_mode mode, - bool wp_copy); + uffd_flags_t flags); #endif /* CONFIG_HUGETLB_PAGE */ static __always_inline ssize_t mfill_atomic_pte(pmd_t *dst_pmd, struct vm_area_struct *dst_vma, unsigned long dst_addr, unsigned long src_addr, - struct page **page, - enum mcopy_atomic_mode mode, - bool wp_copy) + uffd_flags_t flags, + struct page **pagep) { ssize_t err; - if (mode == MCOPY_ATOMIC_CONTINUE) { + if (uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE)) { return mfill_atomic_pte_continue(dst_pmd, dst_vma, - dst_addr, wp_copy); + dst_addr, flags); } /* @@ -496,18 +492,17 @@ static __always_inline ssize_t mfill_atomic_pte(pmd_t *dst_pmd, * and not in the radix tree. */ if (!(dst_vma->vm_flags & VM_SHARED)) { - if (mode == MCOPY_ATOMIC_NORMAL) + if (uffd_flags_mode_is(flags, MFILL_ATOMIC_COPY)) err = mfill_atomic_pte_copy(dst_pmd, dst_vma, - dst_addr, src_addr, page, - wp_copy); + dst_addr, src_addr, + flags, pagep); else err = mfill_atomic_pte_zeropage(dst_pmd, dst_vma, dst_addr); } else { err = shmem_mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, src_addr, - mode != MCOPY_ATOMIC_NORMAL, - wp_copy, page); + flags, pagep); } return err; @@ -517,9 +512,8 @@ static __always_inline ssize_t mfill_atomic(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long src_start, unsigned long len, - enum mcopy_atomic_mode mcopy_mode, atomic_t *mmap_changing, - __u64 mode) + uffd_flags_t flags) { struct vm_area_struct *dst_vma; ssize_t err; @@ -527,7 +521,6 @@ static __always_inline ssize_t mfill_atomic(struct mm_struct *dst_mm, unsigned long src_addr, dst_addr; long copied; struct page *page; - bool wp_copy; /* * Sanitize the command parameters: @@ -577,8 +570,7 @@ retry: * validate 'mode' now that we know the dst_vma: don't allow * a wrprotect copy if the userfaultfd didn't register as WP. */ - wp_copy = mode & UFFDIO_COPY_MODE_WP; - if (wp_copy && !(dst_vma->vm_flags & VM_UFFD_WP)) + if ((flags & MFILL_ATOMIC_WP) && !(dst_vma->vm_flags & VM_UFFD_WP)) goto out_unlock; /* @@ -586,12 +578,12 @@ retry: */ if (is_vm_hugetlb_page(dst_vma)) return mfill_atomic_hugetlb(dst_vma, dst_start, - src_start, len, mcopy_mode, - wp_copy); + src_start, len, flags); if (!vma_is_anonymous(dst_vma) && !vma_is_shmem(dst_vma)) goto out_unlock; - if (!vma_is_shmem(dst_vma) && mcopy_mode == MCOPY_ATOMIC_CONTINUE) + if (!vma_is_shmem(dst_vma) && + uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE)) goto out_unlock; /* @@ -639,7 +631,7 @@ retry: BUG_ON(pmd_trans_huge(*dst_pmd)); err = mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, - src_addr, &page, mcopy_mode, wp_copy); + src_addr, flags, &page); cond_resched(); if (unlikely(err == -ENOENT)) { @@ -687,24 +679,24 @@ out: ssize_t mfill_atomic_copy(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long src_start, unsigned long len, - atomic_t *mmap_changing, __u64 mode) + atomic_t *mmap_changing, uffd_flags_t flags) { - return mfill_atomic(dst_mm, dst_start, src_start, len, - MCOPY_ATOMIC_NORMAL, mmap_changing, mode); + return mfill_atomic(dst_mm, dst_start, src_start, len, mmap_changing, + uffd_flags_set_mode(flags, MFILL_ATOMIC_COPY)); } ssize_t mfill_atomic_zeropage(struct mm_struct *dst_mm, unsigned long start, unsigned long len, atomic_t *mmap_changing) { - return mfill_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_ZEROPAGE, - mmap_changing, 0); + return mfill_atomic(dst_mm, start, 0, len, mmap_changing, + uffd_flags_set_mode(0, MFILL_ATOMIC_ZEROPAGE)); } ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long start, unsigned long len, atomic_t *mmap_changing) { - return mfill_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_CONTINUE, - mmap_changing, 0); + return mfill_atomic(dst_mm, start, 0, len, mmap_changing, + uffd_flags_set_mode(0, MFILL_ATOMIC_CONTINUE)); } long uffd_wp_range(struct vm_area_struct *dst_vma, -- cgit v1.2.3 From 0289184476c845968ad6ac9083c96cc0f75ca505 Mon Sep 17 00:00:00 2001 From: Axel Rasmussen Date: Tue, 14 Mar 2023 15:12:50 -0700 Subject: mm: userfaultfd: add UFFDIO_CONTINUE_MODE_WP to install WP PTEs UFFDIO_COPY already has UFFDIO_COPY_MODE_WP, so when installing a new PTE to resolve a missing fault, one can install a write-protected one. This is useful when using UFFDIO_REGISTER_MODE_{MISSING,WP} in combination. This was motivated by testing HugeTLB HGM [1], and in particular its interaction with userfaultfd features. Existing userfaultfd code supports using WP and MINOR modes together (i.e. you can register an area with both enabled), but without this CONTINUE flag the combination is in practice unusable. So, add an analogous UFFDIO_CONTINUE_MODE_WP, which does the same thing as UFFDIO_COPY_MODE_WP, but for *minor* faults. Update the selftest to do some very basic exercising of the new flag. Update Documentation/ to describe how these flags are used (neither the COPY nor the new CONTINUE versions of this mode flag were described there before). [1]: https://patchwork.kernel.org/project/linux-mm/cover/20230218002819.1486479-1-jthoughton@google.com/ Link: https://lkml.kernel.org/r/20230314221250.682452-5-axelrasmussen@google.com Signed-off-by: Axel Rasmussen Acked-by: Peter Xu Acked-by: Mike Rapoport (IBM) Cc: Al Viro Cc: Hugh Dickins Cc: Jan Kara Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Mike Kravetz Cc: Muchun Song Cc: Nadav Amit Cc: Shuah Khan Signed-off-by: Andrew Morton --- Documentation/admin-guide/mm/userfaultfd.rst | 8 ++++++++ fs/userfaultfd.c | 8 ++++++-- include/linux/userfaultfd_k.h | 3 ++- include/uapi/linux/userfaultfd.h | 7 +++++++ mm/userfaultfd.c | 5 +++-- tools/testing/selftests/mm/userfaultfd.c | 4 ++++ 6 files changed, 30 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/Documentation/admin-guide/mm/userfaultfd.rst b/Documentation/admin-guide/mm/userfaultfd.rst index bd2226299583..7c304e432205 100644 --- a/Documentation/admin-guide/mm/userfaultfd.rst +++ b/Documentation/admin-guide/mm/userfaultfd.rst @@ -236,6 +236,14 @@ newer kernels, one can also detect the feature UFFD_FEATURE_WP_UNPOPULATED and set the feature bit in advance to make sure none ptes will also be write protected even upon anonymous memory. +When using ``UFFDIO_REGISTER_MODE_WP`` in combination with either +``UFFDIO_REGISTER_MODE_MISSING`` or ``UFFDIO_REGISTER_MODE_MINOR``, when +resolving missing / minor faults with ``UFFDIO_COPY`` or ``UFFDIO_CONTINUE`` +respectively, it may be desirable for the new page / mapping to be +write-protected (so future writes will also result in a WP fault). These ioctls +support a mode flag (``UFFDIO_COPY_MODE_WP`` or ``UFFDIO_CONTINUE_MODE_WP`` +respectively) to configure the mapping this way. + QEMU/KVM ======== diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 8971c3613cc6..8395605790f6 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1893,6 +1893,7 @@ static int userfaultfd_continue(struct userfaultfd_ctx *ctx, unsigned long arg) struct uffdio_continue uffdio_continue; struct uffdio_continue __user *user_uffdio_continue; struct userfaultfd_wake_range range; + uffd_flags_t flags = 0; user_uffdio_continue = (struct uffdio_continue __user *)arg; @@ -1917,13 +1918,16 @@ static int userfaultfd_continue(struct userfaultfd_ctx *ctx, unsigned long arg) uffdio_continue.range.start) { goto out; } - if (uffdio_continue.mode & ~UFFDIO_CONTINUE_MODE_DONTWAKE) + if (uffdio_continue.mode & ~(UFFDIO_CONTINUE_MODE_DONTWAKE | + UFFDIO_CONTINUE_MODE_WP)) goto out; + if (uffdio_continue.mode & UFFDIO_CONTINUE_MODE_WP) + flags |= MFILL_ATOMIC_WP; if (mmget_not_zero(ctx->mm)) { ret = mfill_atomic_continue(ctx->mm, uffdio_continue.range.start, uffdio_continue.range.len, - &ctx->mmap_changing); + &ctx->mmap_changing, flags); mmput(ctx->mm); } else { return -ESRCH; diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 4c477dece540..a2c53e98dfd6 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -83,7 +83,8 @@ extern ssize_t mfill_atomic_zeropage(struct mm_struct *dst_mm, unsigned long len, atomic_t *mmap_changing); extern ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long dst_start, - unsigned long len, atomic_t *mmap_changing); + unsigned long len, atomic_t *mmap_changing, + uffd_flags_t flags); extern int mwriteprotect_range(struct mm_struct *dst_mm, unsigned long start, unsigned long len, bool enable_wp, atomic_t *mmap_changing); diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h index 90c958952bfc..66dd4cd277bd 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -305,6 +305,13 @@ struct uffdio_writeprotect { struct uffdio_continue { struct uffdio_range range; #define UFFDIO_CONTINUE_MODE_DONTWAKE ((__u64)1<<0) + /* + * UFFDIO_CONTINUE_MODE_WP will map the page write protected on + * the fly. UFFDIO_CONTINUE_MODE_WP is available only if the + * write protected ioctl is implemented for the range + * according to the uffdio_register.ioctls. + */ +#define UFFDIO_CONTINUE_MODE_WP ((__u64)1<<1) __u64 mode; /* diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index a9b19b39413d..7f1b5f8b712c 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -693,10 +693,11 @@ ssize_t mfill_atomic_zeropage(struct mm_struct *dst_mm, unsigned long start, } ssize_t mfill_atomic_continue(struct mm_struct *dst_mm, unsigned long start, - unsigned long len, atomic_t *mmap_changing) + unsigned long len, atomic_t *mmap_changing, + uffd_flags_t flags) { return mfill_atomic(dst_mm, start, 0, len, mmap_changing, - uffd_flags_set_mode(0, MFILL_ATOMIC_CONTINUE)); + uffd_flags_set_mode(flags, MFILL_ATOMIC_CONTINUE)); } long uffd_wp_range(struct vm_area_struct *dst_vma, diff --git a/tools/testing/selftests/mm/userfaultfd.c b/tools/testing/selftests/mm/userfaultfd.c index e030d63c031a..a96d126cb40e 100644 --- a/tools/testing/selftests/mm/userfaultfd.c +++ b/tools/testing/selftests/mm/userfaultfd.c @@ -585,6 +585,8 @@ static void continue_range(int ufd, __u64 start, __u64 len) req.range.start = start; req.range.len = len; req.mode = 0; + if (test_uffdio_wp) + req.mode |= UFFDIO_CONTINUE_MODE_WP; if (ioctl(ufd, UFFDIO_CONTINUE, &req)) err("UFFDIO_CONTINUE failed for address 0x%" PRIx64, @@ -1332,6 +1334,8 @@ static int userfaultfd_minor_test(void) uffdio_register.range.start = (unsigned long)area_dst_alias; uffdio_register.range.len = nr_pages * page_size; uffdio_register.mode = UFFDIO_REGISTER_MODE_MINOR; + if (test_uffdio_wp) + uffdio_register.mode |= UFFDIO_REGISTER_MODE_WP; if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) err("register failure"); -- cgit v1.2.3 From 5d671eb4ef7e1423a78fc0c12dd419c1dc1f6967 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Sun, 19 Mar 2023 13:42:14 +0200 Subject: mm: move get_page_from_free_area() to mm/page_alloc.c The get_page_from_free_area() helper is only used in mm/page_alloc.c so move it there to reduce noise in include/linux/mmzone.h Link: https://lkml.kernel.org/r/20230319114214.2133332-1-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Reviewed-by: Lorenzo Stoakes Acked-by: Kirill A. Shutemov Reviewed-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 7 ------- mm/page_alloc.c | 7 +++++++ 2 files changed, 7 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 35b11cc210d9..2d3d78d01283 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -108,13 +108,6 @@ struct free_area { unsigned long nr_free; }; -static inline struct page *get_page_from_free_area(struct free_area *area, - int migratetype) -{ - return list_first_entry_or_null(&area->free_list[migratetype], - struct page, lru); -} - static inline bool free_area_empty(struct free_area *area, int migratetype) { return list_empty(&area->free_list[migratetype]); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c3e49d028a7a..4b09711b6f0f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1048,6 +1048,13 @@ static inline void del_page_from_free_list(struct page *page, struct zone *zone, zone->free_area[order].nr_free--; } +static inline struct page *get_page_from_free_area(struct free_area *area, + int migratetype) +{ + return list_first_entry_or_null(&area->free_list[migratetype], + struct page, lru); +} + /* * If this is not the largest possible page, check if the buddy * of the next-highest order is free. If it is, it's possible -- cgit v1.2.3 From 9420f89db2dd611c5b436a13e13f74d65ecc3a6a Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:02 +0200 Subject: mm: move most of core MM initialization to mm/mm_init.c The bulk of memory management initialization code is spread all over mm/page_alloc.c and makes navigating through page allocator functionality difficult. Move most of the functions marked __init and __meminit to mm/mm_init.c to make it better localized and allow some more spare room before mm/page_alloc.c reaches 10k lines. No functional changes. Link: https://lkml.kernel.org/r/20230321170513.2401534-4-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Acked-by: David Hildenbrand Acked-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/gfp.h | 5 - mm/cma.c | 1 + mm/internal.h | 38 +- mm/mm_init.c | 2304 +++++++++++++++++++++++++++++++++++++++++ mm/page_alloc.c | 2866 +++++---------------------------------------------- 5 files changed, 2614 insertions(+), 2600 deletions(-) (limited to 'include') diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 65a78773dcca..7c554e4bd49f 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -361,9 +361,4 @@ extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask, #endif void free_contig_range(unsigned long pfn, unsigned long nr_pages); -#ifdef CONFIG_CMA -/* CMA stuff */ -extern void init_cma_reserved_pageblock(struct page *page); -#endif - #endif /* __LINUX_GFP_H */ diff --git a/mm/cma.c b/mm/cma.c index a7263aa02c92..6268d6620254 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -33,6 +33,7 @@ #include #include +#include "internal.h" #include "cma.h" struct cma cma_areas[MAX_CMA_AREAS]; diff --git a/mm/internal.h b/mm/internal.h index 2a7ffd9962c4..22f1410a0ee3 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -202,6 +202,8 @@ pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); * in mm/page_alloc.c */ +extern char * const zone_names[MAX_NR_ZONES]; + /* * Structure for holding the mostly immutable allocation parameters passed * between functions involved in allocations, including the alloc_pages* @@ -366,7 +368,29 @@ extern void __putback_isolated_page(struct page *page, unsigned int order, extern void memblock_free_pages(struct page *page, unsigned long pfn, unsigned int order); extern void __free_pages_core(struct page *page, unsigned int order); + +static inline void prep_compound_head(struct page *page, unsigned int order) +{ + struct folio *folio = (struct folio *)page; + + set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); + set_compound_order(page, order); + atomic_set(&folio->_entire_mapcount, -1); + atomic_set(&folio->_nr_pages_mapped, 0); + atomic_set(&folio->_pincount, 0); +} + +static inline void prep_compound_tail(struct page *head, int tail_idx) +{ + struct page *p = head + tail_idx; + + p->mapping = TAIL_MAPPING; + set_compound_head(p, head); + set_page_private(p, 0); +} + extern void prep_compound_page(struct page *page, unsigned int order); + extern void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags); extern int user_min_free_kbytes; @@ -377,6 +401,7 @@ extern void free_unref_page_list(struct list_head *list); extern void zone_pcp_reset(struct zone *zone); extern void zone_pcp_disable(struct zone *zone); extern void zone_pcp_enable(struct zone *zone); +extern void zone_pcp_init(struct zone *zone); extern void *memmap_alloc(phys_addr_t size, phys_addr_t align, phys_addr_t min_addr, @@ -474,7 +499,12 @@ isolate_migratepages_range(struct compact_control *cc, int __alloc_contig_migrate_range(struct compact_control *cc, unsigned long start, unsigned long end); -#endif + +/* Free whole pageblock and set its migration type to MIGRATE_CMA. */ +void init_cma_reserved_pageblock(struct page *page); + +#endif /* CONFIG_COMPACTION || CONFIG_CMA */ + int find_suitable_fallback(struct free_area *area, unsigned int order, int migratetype, bool only_stealable, bool *can_steal); @@ -658,6 +688,12 @@ static inline void vunmap_range_noflush(unsigned long start, unsigned long end) #endif /* !CONFIG_MMU */ /* Memory initialisation debug and verification */ +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT +DECLARE_STATIC_KEY_TRUE(deferred_pages); + +bool __init deferred_grow_zone(struct zone *zone, unsigned int order); +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ + enum mminit_level { MMINIT_WARNING, MMINIT_VERIFY, diff --git a/mm/mm_init.c b/mm/mm_init.c index c1883362e71d..68d0187c7886 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -14,7 +14,14 @@ #include #include #include +#include +#include +#include +#include +#include +#include #include "internal.h" +#include "shuffle.h" #ifdef CONFIG_DEBUG_MEMORY_INIT int __meminitdata mminit_loglevel; @@ -198,3 +205,2300 @@ static int __init mm_sysfs_init(void) return 0; } postcore_initcall(mm_sysfs_init); + +static unsigned long arch_zone_lowest_possible_pfn[MAX_NR_ZONES] __initdata; +static unsigned long arch_zone_highest_possible_pfn[MAX_NR_ZONES] __initdata; +static unsigned long zone_movable_pfn[MAX_NUMNODES] __initdata; + +static unsigned long required_kernelcore __initdata; +static unsigned long required_kernelcore_percent __initdata; +static unsigned long required_movablecore __initdata; +static unsigned long required_movablecore_percent __initdata; + +static unsigned long nr_kernel_pages __initdata; +static unsigned long nr_all_pages __initdata; +static unsigned long dma_reserve __initdata; + +bool deferred_struct_pages __meminitdata; + +static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); + +static int __init cmdline_parse_core(char *p, unsigned long *core, + unsigned long *percent) +{ + unsigned long long coremem; + char *endptr; + + if (!p) + return -EINVAL; + + /* Value may be a percentage of total memory, otherwise bytes */ + coremem = simple_strtoull(p, &endptr, 0); + if (*endptr == '%') { + /* Paranoid check for percent values greater than 100 */ + WARN_ON(coremem > 100); + + *percent = coremem; + } else { + coremem = memparse(p, &p); + /* Paranoid check that UL is enough for the coremem value */ + WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX); + + *core = coremem >> PAGE_SHIFT; + *percent = 0UL; + } + return 0; +} + +/* + * kernelcore=size sets the amount of memory for use for allocations that + * cannot be reclaimed or migrated. + */ +static int __init cmdline_parse_kernelcore(char *p) +{ + /* parse kernelcore=mirror */ + if (parse_option_str(p, "mirror")) { + mirrored_kernelcore = true; + return 0; + } + + return cmdline_parse_core(p, &required_kernelcore, + &required_kernelcore_percent); +} +early_param("kernelcore", cmdline_parse_kernelcore); + +/* + * movablecore=size sets the amount of memory for use for allocations that + * can be reclaimed or migrated. + */ +static int __init cmdline_parse_movablecore(char *p) +{ + return cmdline_parse_core(p, &required_movablecore, + &required_movablecore_percent); +} +early_param("movablecore", cmdline_parse_movablecore); + +/* + * early_calculate_totalpages() + * Sum pages in active regions for movable zone. + * Populate N_MEMORY for calculating usable_nodes. + */ +static unsigned long __init early_calculate_totalpages(void) +{ + unsigned long totalpages = 0; + unsigned long start_pfn, end_pfn; + int i, nid; + + for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { + unsigned long pages = end_pfn - start_pfn; + + totalpages += pages; + if (pages) + node_set_state(nid, N_MEMORY); + } + return totalpages; +} + +/* + * This finds a zone that can be used for ZONE_MOVABLE pages. The + * assumption is made that zones within a node are ordered in monotonic + * increasing memory addresses so that the "highest" populated zone is used + */ +static void __init find_usable_zone_for_movable(void) +{ + int zone_index; + for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) { + if (zone_index == ZONE_MOVABLE) + continue; + + if (arch_zone_highest_possible_pfn[zone_index] > + arch_zone_lowest_possible_pfn[zone_index]) + break; + } + + VM_BUG_ON(zone_index == -1); + movable_zone = zone_index; +} + +/* + * Find the PFN the Movable zone begins in each node. Kernel memory + * is spread evenly between nodes as long as the nodes have enough + * memory. When they don't, some nodes will have more kernelcore than + * others + */ +static void __init find_zone_movable_pfns_for_nodes(void) +{ + int i, nid; + unsigned long usable_startpfn; + unsigned long kernelcore_node, kernelcore_remaining; + /* save the state before borrow the nodemask */ + nodemask_t saved_node_state = node_states[N_MEMORY]; + unsigned long totalpages = early_calculate_totalpages(); + int usable_nodes = nodes_weight(node_states[N_MEMORY]); + struct memblock_region *r; + + /* Need to find movable_zone earlier when movable_node is specified. */ + find_usable_zone_for_movable(); + + /* + * If movable_node is specified, ignore kernelcore and movablecore + * options. + */ + if (movable_node_is_enabled()) { + for_each_mem_region(r) { + if (!memblock_is_hotpluggable(r)) + continue; + + nid = memblock_get_region_node(r); + + usable_startpfn = PFN_DOWN(r->base); + zone_movable_pfn[nid] = zone_movable_pfn[nid] ? + min(usable_startpfn, zone_movable_pfn[nid]) : + usable_startpfn; + } + + goto out2; + } + + /* + * If kernelcore=mirror is specified, ignore movablecore option + */ + if (mirrored_kernelcore) { + bool mem_below_4gb_not_mirrored = false; + + for_each_mem_region(r) { + if (memblock_is_mirror(r)) + continue; + + nid = memblock_get_region_node(r); + + usable_startpfn = memblock_region_memory_base_pfn(r); + + if (usable_startpfn < PHYS_PFN(SZ_4G)) { + mem_below_4gb_not_mirrored = true; + continue; + } + + zone_movable_pfn[nid] = zone_movable_pfn[nid] ? + min(usable_startpfn, zone_movable_pfn[nid]) : + usable_startpfn; + } + + if (mem_below_4gb_not_mirrored) + pr_warn("This configuration results in unmirrored kernel memory.\n"); + + goto out2; + } + + /* + * If kernelcore=nn% or movablecore=nn% was specified, calculate the + * amount of necessary memory. + */ + if (required_kernelcore_percent) + required_kernelcore = (totalpages * 100 * required_kernelcore_percent) / + 10000UL; + if (required_movablecore_percent) + required_movablecore = (totalpages * 100 * required_movablecore_percent) / + 10000UL; + + /* + * If movablecore= was specified, calculate what size of + * kernelcore that corresponds so that memory usable for + * any allocation type is evenly spread. If both kernelcore + * and movablecore are specified, then the value of kernelcore + * will be used for required_kernelcore if it's greater than + * what movablecore would have allowed. + */ + if (required_movablecore) { + unsigned long corepages; + + /* + * Round-up so that ZONE_MOVABLE is at least as large as what + * was requested by the user + */ + required_movablecore = + roundup(required_movablecore, MAX_ORDER_NR_PAGES); + required_movablecore = min(totalpages, required_movablecore); + corepages = totalpages - required_movablecore; + + required_kernelcore = max(required_kernelcore, corepages); + } + + /* + * If kernelcore was not specified or kernelcore size is larger + * than totalpages, there is no ZONE_MOVABLE. + */ + if (!required_kernelcore || required_kernelcore >= totalpages) + goto out; + + /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */ + usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone]; + +restart: + /* Spread kernelcore memory as evenly as possible throughout nodes */ + kernelcore_node = required_kernelcore / usable_nodes; + for_each_node_state(nid, N_MEMORY) { + unsigned long start_pfn, end_pfn; + + /* + * Recalculate kernelcore_node if the division per node + * now exceeds what is necessary to satisfy the requested + * amount of memory for the kernel + */ + if (required_kernelcore < kernelcore_node) + kernelcore_node = required_kernelcore / usable_nodes; + + /* + * As the map is walked, we track how much memory is usable + * by the kernel using kernelcore_remaining. When it is + * 0, the rest of the node is usable by ZONE_MOVABLE + */ + kernelcore_remaining = kernelcore_node; + + /* Go through each range of PFNs within this node */ + for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { + unsigned long size_pages; + + start_pfn = max(start_pfn, zone_movable_pfn[nid]); + if (start_pfn >= end_pfn) + continue; + + /* Account for what is only usable for kernelcore */ + if (start_pfn < usable_startpfn) { + unsigned long kernel_pages; + kernel_pages = min(end_pfn, usable_startpfn) + - start_pfn; + + kernelcore_remaining -= min(kernel_pages, + kernelcore_remaining); + required_kernelcore -= min(kernel_pages, + required_kernelcore); + + /* Continue if range is now fully accounted */ + if (end_pfn <= usable_startpfn) { + + /* + * Push zone_movable_pfn to the end so + * that if we have to rebalance + * kernelcore across nodes, we will + * not double account here + */ + zone_movable_pfn[nid] = end_pfn; + continue; + } + start_pfn = usable_startpfn; + } + + /* + * The usable PFN range for ZONE_MOVABLE is from + * start_pfn->end_pfn. Calculate size_pages as the + * number of pages used as kernelcore + */ + size_pages = end_pfn - start_pfn; + if (size_pages > kernelcore_remaining) + size_pages = kernelcore_remaining; + zone_movable_pfn[nid] = start_pfn + size_pages; + + /* + * Some kernelcore has been met, update counts and + * break if the kernelcore for this node has been + * satisfied + */ + required_kernelcore -= min(required_kernelcore, + size_pages); + kernelcore_remaining -= size_pages; + if (!kernelcore_remaining) + break; + } + } + + /* + * If there is still required_kernelcore, we do another pass with one + * less node in the count. This will push zone_movable_pfn[nid] further + * along on the nodes that still have memory until kernelcore is + * satisfied + */ + usable_nodes--; + if (usable_nodes && required_kernelcore > usable_nodes) + goto restart; + +out2: + /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */ + for (nid = 0; nid < MAX_NUMNODES; nid++) { + unsigned long start_pfn, end_pfn; + + zone_movable_pfn[nid] = + roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES); + + get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); + if (zone_movable_pfn[nid] >= end_pfn) + zone_movable_pfn[nid] = 0; + } + +out: + /* restore the node_state */ + node_states[N_MEMORY] = saved_node_state; +} + +static void __meminit __init_single_page(struct page *page, unsigned long pfn, + unsigned long zone, int nid) +{ + mm_zero_struct_page(page); + set_page_links(page, zone, nid, pfn); + init_page_count(page); + page_mapcount_reset(page); + page_cpupid_reset_last(page); + page_kasan_tag_reset(page); + + INIT_LIST_HEAD(&page->lru); +#ifdef WANT_PAGE_VIRTUAL + /* The shift won't overflow because ZONE_NORMAL is below 4G. */ + if (!is_highmem_idx(zone)) + set_page_address(page, __va(pfn << PAGE_SHIFT)); +#endif +} + +#ifdef CONFIG_NUMA +/* + * During memory init memblocks map pfns to nids. The search is expensive and + * this caches recent lookups. The implementation of __early_pfn_to_nid + * treats start/end as pfns. + */ +struct mminit_pfnnid_cache { + unsigned long last_start; + unsigned long last_end; + int last_nid; +}; + +static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata; + +/* + * Required by SPARSEMEM. Given a PFN, return what node the PFN is on. + */ +static int __meminit __early_pfn_to_nid(unsigned long pfn, + struct mminit_pfnnid_cache *state) +{ + unsigned long start_pfn, end_pfn; + int nid; + + if (state->last_start <= pfn && pfn < state->last_end) + return state->last_nid; + + nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn); + if (nid != NUMA_NO_NODE) { + state->last_start = start_pfn; + state->last_end = end_pfn; + state->last_nid = nid; + } + + return nid; +} + +int __meminit early_pfn_to_nid(unsigned long pfn) +{ + static DEFINE_SPINLOCK(early_pfn_lock); + int nid; + + spin_lock(&early_pfn_lock); + nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache); + if (nid < 0) + nid = first_online_node; + spin_unlock(&early_pfn_lock); + + return nid; +} +#endif /* CONFIG_NUMA */ + +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT +static inline void pgdat_set_deferred_range(pg_data_t *pgdat) +{ + pgdat->first_deferred_pfn = ULONG_MAX; +} + +/* Returns true if the struct page for the pfn is initialised */ +static inline bool __meminit early_page_initialised(unsigned long pfn) +{ + int nid = early_pfn_to_nid(pfn); + + if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn) + return false; + + return true; +} + +/* + * Returns true when the remaining initialisation should be deferred until + * later in the boot cycle when it can be parallelised. + */ +static bool __meminit +defer_init(int nid, unsigned long pfn, unsigned long end_pfn) +{ + static unsigned long prev_end_pfn, nr_initialised; + + if (early_page_ext_enabled()) + return false; + /* + * prev_end_pfn static that contains the end of previous zone + * No need to protect because called very early in boot before smp_init. + */ + if (prev_end_pfn != end_pfn) { + prev_end_pfn = end_pfn; + nr_initialised = 0; + } + + /* Always populate low zones for address-constrained allocations */ + if (end_pfn < pgdat_end_pfn(NODE_DATA(nid))) + return false; + + if (NODE_DATA(nid)->first_deferred_pfn != ULONG_MAX) + return true; + /* + * We start only with one section of pages, more pages are added as + * needed until the rest of deferred pages are initialized. + */ + nr_initialised++; + if ((nr_initialised > PAGES_PER_SECTION) && + (pfn & (PAGES_PER_SECTION - 1)) == 0) { + NODE_DATA(nid)->first_deferred_pfn = pfn; + return true; + } + return false; +} + +static void __meminit init_reserved_page(unsigned long pfn) +{ + pg_data_t *pgdat; + int nid, zid; + + if (early_page_initialised(pfn)) + return; + + nid = early_pfn_to_nid(pfn); + pgdat = NODE_DATA(nid); + + for (zid = 0; zid < MAX_NR_ZONES; zid++) { + struct zone *zone = &pgdat->node_zones[zid]; + + if (zone_spans_pfn(zone, pfn)) + break; + } + __init_single_page(pfn_to_page(pfn), pfn, zid, nid); +} +#else +static inline void pgdat_set_deferred_range(pg_data_t *pgdat) {} + +static inline bool early_page_initialised(unsigned long pfn) +{ + return true; +} + +static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn) +{ + return false; +} + +static inline void init_reserved_page(unsigned long pfn) +{ +} +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ + +/* + * Initialised pages do not have PageReserved set. This function is + * called for each range allocated by the bootmem allocator and + * marks the pages PageReserved. The remaining valid pages are later + * sent to the buddy page allocator. + */ +void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end) +{ + unsigned long start_pfn = PFN_DOWN(start); + unsigned long end_pfn = PFN_UP(end); + + for (; start_pfn < end_pfn; start_pfn++) { + if (pfn_valid(start_pfn)) { + struct page *page = pfn_to_page(start_pfn); + + init_reserved_page(start_pfn); + + /* Avoid false-positive PageTail() */ + INIT_LIST_HEAD(&page->lru); + + /* + * no need for atomic set_bit because the struct + * page is not visible yet so nobody should + * access it yet. + */ + __SetPageReserved(page); + } + } +} + +/* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */ +static bool __meminit +overlap_memmap_init(unsigned long zone, unsigned long *pfn) +{ + static struct memblock_region *r; + + if (mirrored_kernelcore && zone == ZONE_MOVABLE) { + if (!r || *pfn >= memblock_region_memory_end_pfn(r)) { + for_each_mem_region(r) { + if (*pfn < memblock_region_memory_end_pfn(r)) + break; + } + } + if (*pfn >= memblock_region_memory_base_pfn(r) && + memblock_is_mirror(r)) { + *pfn = memblock_region_memory_end_pfn(r); + return true; + } + } + return false; +} + +/* + * Only struct pages that correspond to ranges defined by memblock.memory + * are zeroed and initialized by going through __init_single_page() during + * memmap_init_zone_range(). + * + * But, there could be struct pages that correspond to holes in + * memblock.memory. This can happen because of the following reasons: + * - physical memory bank size is not necessarily the exact multiple of the + * arbitrary section size + * - early reserved memory may not be listed in memblock.memory + * - memory layouts defined with memmap= kernel parameter may not align + * nicely with memmap sections + * + * Explicitly initialize those struct pages so that: + * - PG_Reserved is set + * - zone and node links point to zone and node that span the page if the + * hole is in the middle of a zone + * - zone and node links point to adjacent zone/node if the hole falls on + * the zone boundary; the pages in such holes will be prepended to the + * zone/node above the hole except for the trailing pages in the last + * section that will be appended to the zone/node below. + */ +static void __init init_unavailable_range(unsigned long spfn, + unsigned long epfn, + int zone, int node) +{ + unsigned long pfn; + u64 pgcnt = 0; + + for (pfn = spfn; pfn < epfn; pfn++) { + if (!pfn_valid(pageblock_start_pfn(pfn))) { + pfn = pageblock_end_pfn(pfn) - 1; + continue; + } + __init_single_page(pfn_to_page(pfn), pfn, zone, node); + __SetPageReserved(pfn_to_page(pfn)); + pgcnt++; + } + + if (pgcnt) + pr_info("On node %d, zone %s: %lld pages in unavailable ranges", + node, zone_names[zone], pgcnt); +} + +/* + * Initially all pages are reserved - free ones are freed + * up by memblock_free_all() once the early boot process is + * done. Non-atomic initialization, single-pass. + * + * All aligned pageblocks are initialized to the specified migratetype + * (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related + * zone stats (e.g., nr_isolate_pageblock) are touched. + */ +void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone, + unsigned long start_pfn, unsigned long zone_end_pfn, + enum meminit_context context, + struct vmem_altmap *altmap, int migratetype) +{ + unsigned long pfn, end_pfn = start_pfn + size; + struct page *page; + + if (highest_memmap_pfn < end_pfn - 1) + highest_memmap_pfn = end_pfn - 1; + +#ifdef CONFIG_ZONE_DEVICE + /* + * Honor reservation requested by the driver for this ZONE_DEVICE + * memory. We limit the total number of pages to initialize to just + * those that might contain the memory mapping. We will defer the + * ZONE_DEVICE page initialization until after we have released + * the hotplug lock. + */ + if (zone == ZONE_DEVICE) { + if (!altmap) + return; + + if (start_pfn == altmap->base_pfn) + start_pfn += altmap->reserve; + end_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); + } +#endif + + for (pfn = start_pfn; pfn < end_pfn; ) { + /* + * There can be holes in boot-time mem_map[]s handed to this + * function. They do not exist on hotplugged memory. + */ + if (context == MEMINIT_EARLY) { + if (overlap_memmap_init(zone, &pfn)) + continue; + if (defer_init(nid, pfn, zone_end_pfn)) { + deferred_struct_pages = true; + break; + } + } + + page = pfn_to_page(pfn); + __init_single_page(page, pfn, zone, nid); + if (context == MEMINIT_HOTPLUG) + __SetPageReserved(page); + + /* + * Usually, we want to mark the pageblock MIGRATE_MOVABLE, + * such that unmovable allocations won't be scattered all + * over the place during system boot. + */ + if (pageblock_aligned(pfn)) { + set_pageblock_migratetype(page, migratetype); + cond_resched(); + } + pfn++; + } +} + +static void __init memmap_init_zone_range(struct zone *zone, + unsigned long start_pfn, + unsigned long end_pfn, + unsigned long *hole_pfn) +{ + unsigned long zone_start_pfn = zone->zone_start_pfn; + unsigned long zone_end_pfn = zone_start_pfn + zone->spanned_pages; + int nid = zone_to_nid(zone), zone_id = zone_idx(zone); + + start_pfn = clamp(start_pfn, zone_start_pfn, zone_end_pfn); + end_pfn = clamp(end_pfn, zone_start_pfn, zone_end_pfn); + + if (start_pfn >= end_pfn) + return; + + memmap_init_range(end_pfn - start_pfn, nid, zone_id, start_pfn, + zone_end_pfn, MEMINIT_EARLY, NULL, MIGRATE_MOVABLE); + + if (*hole_pfn < start_pfn) + init_unavailable_range(*hole_pfn, start_pfn, zone_id, nid); + + *hole_pfn = end_pfn; +} + +static void __init memmap_init(void) +{ + unsigned long start_pfn, end_pfn; + unsigned long hole_pfn = 0; + int i, j, zone_id = 0, nid; + + for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { + struct pglist_data *node = NODE_DATA(nid); + + for (j = 0; j < MAX_NR_ZONES; j++) { + struct zone *zone = node->node_zones + j; + + if (!populated_zone(zone)) + continue; + + memmap_init_zone_range(zone, start_pfn, end_pfn, + &hole_pfn); + zone_id = j; + } + } + +#ifdef CONFIG_SPARSEMEM + /* + * Initialize the memory map for hole in the range [memory_end, + * section_end]. + * Append the pages in this hole to the highest zone in the last + * node. + * The call to init_unavailable_range() is outside the ifdef to + * silence the compiler warining about zone_id set but not used; + * for FLATMEM it is a nop anyway + */ + end_pfn = round_up(end_pfn, PAGES_PER_SECTION); + if (hole_pfn < end_pfn) +#endif + init_unavailable_range(hole_pfn, end_pfn, zone_id, nid); +} + +#ifdef CONFIG_ZONE_DEVICE +static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, + unsigned long zone_idx, int nid, + struct dev_pagemap *pgmap) +{ + + __init_single_page(page, pfn, zone_idx, nid); + + /* + * Mark page reserved as it will need to wait for onlining + * phase for it to be fully associated with a zone. + * + * We can use the non-atomic __set_bit operation for setting + * the flag as we are still initializing the pages. + */ + __SetPageReserved(page); + + /* + * ZONE_DEVICE pages union ->lru with a ->pgmap back pointer + * and zone_device_data. It is a bug if a ZONE_DEVICE page is + * ever freed or placed on a driver-private list. + */ + page->pgmap = pgmap; + page->zone_device_data = NULL; + + /* + * Mark the block movable so that blocks are reserved for + * movable at startup. This will force kernel allocations + * to reserve their blocks rather than leaking throughout + * the address space during boot when many long-lived + * kernel allocations are made. + * + * Please note that MEMINIT_HOTPLUG path doesn't clear memmap + * because this is done early in section_activate() + */ + if (pageblock_aligned(pfn)) { + set_pageblock_migratetype(page, MIGRATE_MOVABLE); + cond_resched(); + } + + /* + * ZONE_DEVICE pages are released directly to the driver page allocator + * which will set the page count to 1 when allocating the page. + */ + if (pgmap->type == MEMORY_DEVICE_PRIVATE || + pgmap->type == MEMORY_DEVICE_COHERENT) + set_page_count(page, 0); +} + +/* + * With compound page geometry and when struct pages are stored in ram most + * tail pages are reused. Consequently, the amount of unique struct pages to + * initialize is a lot smaller that the total amount of struct pages being + * mapped. This is a paired / mild layering violation with explicit knowledge + * of how the sparse_vmemmap internals handle compound pages in the lack + * of an altmap. See vmemmap_populate_compound_pages(). + */ +static inline unsigned long compound_nr_pages(struct vmem_altmap *altmap, + unsigned long nr_pages) +{ + return is_power_of_2(sizeof(struct page)) && + !altmap ? 2 * (PAGE_SIZE / sizeof(struct page)) : nr_pages; +} + +static void __ref memmap_init_compound(struct page *head, + unsigned long head_pfn, + unsigned long zone_idx, int nid, + struct dev_pagemap *pgmap, + unsigned long nr_pages) +{ + unsigned long pfn, end_pfn = head_pfn + nr_pages; + unsigned int order = pgmap->vmemmap_shift; + + __SetPageHead(head); + for (pfn = head_pfn + 1; pfn < end_pfn; pfn++) { + struct page *page = pfn_to_page(pfn); + + __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); + prep_compound_tail(head, pfn - head_pfn); + set_page_count(page, 0); + + /* + * The first tail page stores important compound page info. + * Call prep_compound_head() after the first tail page has + * been initialized, to not have the data overwritten. + */ + if (pfn == head_pfn + 1) + prep_compound_head(head, order); + } +} + +void __ref memmap_init_zone_device(struct zone *zone, + unsigned long start_pfn, + unsigned long nr_pages, + struct dev_pagemap *pgmap) +{ + unsigned long pfn, end_pfn = start_pfn + nr_pages; + struct pglist_data *pgdat = zone->zone_pgdat; + struct vmem_altmap *altmap = pgmap_altmap(pgmap); + unsigned int pfns_per_compound = pgmap_vmemmap_nr(pgmap); + unsigned long zone_idx = zone_idx(zone); + unsigned long start = jiffies; + int nid = pgdat->node_id; + + if (WARN_ON_ONCE(!pgmap || zone_idx != ZONE_DEVICE)) + return; + + /* + * The call to memmap_init should have already taken care + * of the pages reserved for the memmap, so we can just jump to + * the end of that region and start processing the device pages. + */ + if (altmap) { + start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); + nr_pages = end_pfn - start_pfn; + } + + for (pfn = start_pfn; pfn < end_pfn; pfn += pfns_per_compound) { + struct page *page = pfn_to_page(pfn); + + __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); + + if (pfns_per_compound == 1) + continue; + + memmap_init_compound(page, pfn, zone_idx, nid, pgmap, + compound_nr_pages(altmap, pfns_per_compound)); + } + + pr_info("%s initialised %lu pages in %ums\n", __func__, + nr_pages, jiffies_to_msecs(jiffies - start)); +} +#endif + +/* + * The zone ranges provided by the architecture do not include ZONE_MOVABLE + * because it is sized independent of architecture. Unlike the other zones, + * the starting point for ZONE_MOVABLE is not fixed. It may be different + * in each node depending on the size of each node and how evenly kernelcore + * is distributed. This helper function adjusts the zone ranges + * provided by the architecture for a given node by using the end of the + * highest usable zone for ZONE_MOVABLE. This preserves the assumption that + * zones within a node are in order of monotonic increases memory addresses + */ +static void __init adjust_zone_range_for_zone_movable(int nid, + unsigned long zone_type, + unsigned long node_start_pfn, + unsigned long node_end_pfn, + unsigned long *zone_start_pfn, + unsigned long *zone_end_pfn) +{ + /* Only adjust if ZONE_MOVABLE is on this node */ + if (zone_movable_pfn[nid]) { + /* Size ZONE_MOVABLE */ + if (zone_type == ZONE_MOVABLE) { + *zone_start_pfn = zone_movable_pfn[nid]; + *zone_end_pfn = min(node_end_pfn, + arch_zone_highest_possible_pfn[movable_zone]); + + /* Adjust for ZONE_MOVABLE starting within this range */ + } else if (!mirrored_kernelcore && + *zone_start_pfn < zone_movable_pfn[nid] && + *zone_end_pfn > zone_movable_pfn[nid]) { + *zone_end_pfn = zone_movable_pfn[nid]; + + /* Check if this whole range is within ZONE_MOVABLE */ + } else if (*zone_start_pfn >= zone_movable_pfn[nid]) + *zone_start_pfn = *zone_end_pfn; + } +} + +/* + * Return the number of holes in a range on a node. If nid is MAX_NUMNODES, + * then all holes in the requested range will be accounted for. + */ +unsigned long __init __absent_pages_in_range(int nid, + unsigned long range_start_pfn, + unsigned long range_end_pfn) +{ + unsigned long nr_absent = range_end_pfn - range_start_pfn; + unsigned long start_pfn, end_pfn; + int i; + + for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { + start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn); + end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn); + nr_absent -= end_pfn - start_pfn; + } + return nr_absent; +} + +/** + * absent_pages_in_range - Return number of page frames in holes within a range + * @start_pfn: The start PFN to start searching for holes + * @end_pfn: The end PFN to stop searching for holes + * + * Return: the number of pages frames in memory holes within a range. + */ +unsigned long __init absent_pages_in_range(unsigned long start_pfn, + unsigned long end_pfn) +{ + return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn); +} + +/* Return the number of page frames in holes in a zone on a node */ +static unsigned long __init zone_absent_pages_in_node(int nid, + unsigned long zone_type, + unsigned long node_start_pfn, + unsigned long node_end_pfn) +{ + unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; + unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; + unsigned long zone_start_pfn, zone_end_pfn; + unsigned long nr_absent; + + /* When hotadd a new node from cpu_up(), the node should be empty */ + if (!node_start_pfn && !node_end_pfn) + return 0; + + zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); + zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); + + adjust_zone_range_for_zone_movable(nid, zone_type, + node_start_pfn, node_end_pfn, + &zone_start_pfn, &zone_end_pfn); + nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); + + /* + * ZONE_MOVABLE handling. + * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages + * and vice versa. + */ + if (mirrored_kernelcore && zone_movable_pfn[nid]) { + unsigned long start_pfn, end_pfn; + struct memblock_region *r; + + for_each_mem_region(r) { + start_pfn = clamp(memblock_region_memory_base_pfn(r), + zone_start_pfn, zone_end_pfn); + end_pfn = clamp(memblock_region_memory_end_pfn(r), + zone_start_pfn, zone_end_pfn); + + if (zone_type == ZONE_MOVABLE && + memblock_is_mirror(r)) + nr_absent += end_pfn - start_pfn; + + if (zone_type == ZONE_NORMAL && + !memblock_is_mirror(r)) + nr_absent += end_pfn - start_pfn; + } + } + + return nr_absent; +} + +/* + * Return the number of pages a zone spans in a node, including holes + * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node() + */ +static unsigned long __init zone_spanned_pages_in_node(int nid, + unsigned long zone_type, + unsigned long node_start_pfn, + unsigned long node_end_pfn, + unsigned long *zone_start_pfn, + unsigned long *zone_end_pfn) +{ + unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; + unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; + /* When hotadd a new node from cpu_up(), the node should be empty */ + if (!node_start_pfn && !node_end_pfn) + return 0; + + /* Get the start and end of the zone */ + *zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); + *zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); + adjust_zone_range_for_zone_movable(nid, zone_type, + node_start_pfn, node_end_pfn, + zone_start_pfn, zone_end_pfn); + + /* Check that this node has pages within the zone's required range */ + if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn) + return 0; + + /* Move the zone boundaries inside the node if necessary */ + *zone_end_pfn = min(*zone_end_pfn, node_end_pfn); + *zone_start_pfn = max(*zone_start_pfn, node_start_pfn); + + /* Return the spanned pages */ + return *zone_end_pfn - *zone_start_pfn; +} + +static void __init calculate_node_totalpages(struct pglist_data *pgdat, + unsigned long node_start_pfn, + unsigned long node_end_pfn) +{ + unsigned long realtotalpages = 0, totalpages = 0; + enum zone_type i; + + for (i = 0; i < MAX_NR_ZONES; i++) { + struct zone *zone = pgdat->node_zones + i; + unsigned long zone_start_pfn, zone_end_pfn; + unsigned long spanned, absent; + unsigned long size, real_size; + + spanned = zone_spanned_pages_in_node(pgdat->node_id, i, + node_start_pfn, + node_end_pfn, + &zone_start_pfn, + &zone_end_pfn); + absent = zone_absent_pages_in_node(pgdat->node_id, i, + node_start_pfn, + node_end_pfn); + + size = spanned; + real_size = size - absent; + + if (size) + zone->zone_start_pfn = zone_start_pfn; + else + zone->zone_start_pfn = 0; + zone->spanned_pages = size; + zone->present_pages = real_size; +#if defined(CONFIG_MEMORY_HOTPLUG) + zone->present_early_pages = real_size; +#endif + + totalpages += size; + realtotalpages += real_size; + } + + pgdat->node_spanned_pages = totalpages; + pgdat->node_present_pages = realtotalpages; + pr_debug("On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages); +} + +static unsigned long __init calc_memmap_size(unsigned long spanned_pages, + unsigned long present_pages) +{ + unsigned long pages = spanned_pages; + + /* + * Provide a more accurate estimation if there are holes within + * the zone and SPARSEMEM is in use. If there are holes within the + * zone, each populated memory region may cost us one or two extra + * memmap pages due to alignment because memmap pages for each + * populated regions may not be naturally aligned on page boundary. + * So the (present_pages >> 4) heuristic is a tradeoff for that. + */ + if (spanned_pages > present_pages + (present_pages >> 4) && + IS_ENABLED(CONFIG_SPARSEMEM)) + pages = present_pages; + + return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT; +} + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static void pgdat_init_split_queue(struct pglist_data *pgdat) +{ + struct deferred_split *ds_queue = &pgdat->deferred_split_queue; + + spin_lock_init(&ds_queue->split_queue_lock); + INIT_LIST_HEAD(&ds_queue->split_queue); + ds_queue->split_queue_len = 0; +} +#else +static void pgdat_init_split_queue(struct pglist_data *pgdat) {} +#endif + +#ifdef CONFIG_COMPACTION +static void pgdat_init_kcompactd(struct pglist_data *pgdat) +{ + init_waitqueue_head(&pgdat->kcompactd_wait); +} +#else +static void pgdat_init_kcompactd(struct pglist_data *pgdat) {} +#endif + +static void __meminit pgdat_init_internals(struct pglist_data *pgdat) +{ + int i; + + pgdat_resize_init(pgdat); + pgdat_kswapd_lock_init(pgdat); + + pgdat_init_split_queue(pgdat); + pgdat_init_kcompactd(pgdat); + + init_waitqueue_head(&pgdat->kswapd_wait); + init_waitqueue_head(&pgdat->pfmemalloc_wait); + + for (i = 0; i < NR_VMSCAN_THROTTLE; i++) + init_waitqueue_head(&pgdat->reclaim_wait[i]); + + pgdat_page_ext_init(pgdat); + lruvec_init(&pgdat->__lruvec); +} + +static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx, int nid, + unsigned long remaining_pages) +{ + atomic_long_set(&zone->managed_pages, remaining_pages); + zone_set_nid(zone, nid); + zone->name = zone_names[idx]; + zone->zone_pgdat = NODE_DATA(nid); + spin_lock_init(&zone->lock); + zone_seqlock_init(zone); + zone_pcp_init(zone); +} + +static void __meminit zone_init_free_lists(struct zone *zone) +{ + unsigned int order, t; + for_each_migratetype_order(order, t) { + INIT_LIST_HEAD(&zone->free_area[order].free_list[t]); + zone->free_area[order].nr_free = 0; + } +} + +void __meminit init_currently_empty_zone(struct zone *zone, + unsigned long zone_start_pfn, + unsigned long size) +{ + struct pglist_data *pgdat = zone->zone_pgdat; + int zone_idx = zone_idx(zone) + 1; + + if (zone_idx > pgdat->nr_zones) + pgdat->nr_zones = zone_idx; + + zone->zone_start_pfn = zone_start_pfn; + + mminit_dprintk(MMINIT_TRACE, "memmap_init", + "Initialising map node %d zone %lu pfns %lu -> %lu\n", + pgdat->node_id, + (unsigned long)zone_idx(zone), + zone_start_pfn, (zone_start_pfn + size)); + + zone_init_free_lists(zone); + zone->initialized = 1; +} + +#ifndef CONFIG_SPARSEMEM +/* + * Calculate the size of the zone->blockflags rounded to an unsigned long + * Start by making sure zonesize is a multiple of pageblock_order by rounding + * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally + * round what is now in bits to nearest long in bits, then return it in + * bytes. + */ +static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize) +{ + unsigned long usemapsize; + + zonesize += zone_start_pfn & (pageblock_nr_pages-1); + usemapsize = roundup(zonesize, pageblock_nr_pages); + usemapsize = usemapsize >> pageblock_order; + usemapsize *= NR_PAGEBLOCK_BITS; + usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long)); + + return usemapsize / 8; +} + +static void __ref setup_usemap(struct zone *zone) +{ + unsigned long usemapsize = usemap_size(zone->zone_start_pfn, + zone->spanned_pages); + zone->pageblock_flags = NULL; + if (usemapsize) { + zone->pageblock_flags = + memblock_alloc_node(usemapsize, SMP_CACHE_BYTES, + zone_to_nid(zone)); + if (!zone->pageblock_flags) + panic("Failed to allocate %ld bytes for zone %s pageblock flags on node %d\n", + usemapsize, zone->name, zone_to_nid(zone)); + } +} +#else +static inline void setup_usemap(struct zone *zone) {} +#endif /* CONFIG_SPARSEMEM */ + +#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE + +/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ +void __init set_pageblock_order(void) +{ + unsigned int order = MAX_ORDER; + + /* Check that pageblock_nr_pages has not already been setup */ + if (pageblock_order) + return; + + /* Don't let pageblocks exceed the maximum allocation granularity. */ + if (HPAGE_SHIFT > PAGE_SHIFT && HUGETLB_PAGE_ORDER < order) + order = HUGETLB_PAGE_ORDER; + + /* + * Assume the largest contiguous order of interest is a huge page. + * This value may be variable depending on boot parameters on IA64 and + * powerpc. + */ + pageblock_order = order; +} +#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ + +/* + * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() + * is unused as pageblock_order is set at compile-time. See + * include/linux/pageblock-flags.h for the values of pageblock_order based on + * the kernel config + */ +void __init set_pageblock_order(void) +{ +} + +#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ + +/* + * Set up the zone data structures + * - init pgdat internals + * - init all zones belonging to this node + * + * NOTE: this function is only called during memory hotplug + */ +#ifdef CONFIG_MEMORY_HOTPLUG +void __ref free_area_init_core_hotplug(struct pglist_data *pgdat) +{ + int nid = pgdat->node_id; + enum zone_type z; + int cpu; + + pgdat_init_internals(pgdat); + + if (pgdat->per_cpu_nodestats == &boot_nodestats) + pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); + + /* + * Reset the nr_zones, order and highest_zoneidx before reuse. + * Note that kswapd will init kswapd_highest_zoneidx properly + * when it starts in the near future. + */ + pgdat->nr_zones = 0; + pgdat->kswapd_order = 0; + pgdat->kswapd_highest_zoneidx = 0; + pgdat->node_start_pfn = 0; + for_each_online_cpu(cpu) { + struct per_cpu_nodestat *p; + + p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu); + memset(p, 0, sizeof(*p)); + } + + for (z = 0; z < MAX_NR_ZONES; z++) + zone_init_internals(&pgdat->node_zones[z], z, nid, 0); +} +#endif + +/* + * Set up the zone data structures: + * - mark all pages reserved + * - mark all memory queues empty + * - clear the memory bitmaps + * + * NOTE: pgdat should get zeroed by caller. + * NOTE: this function is only called during early init. + */ +static void __init free_area_init_core(struct pglist_data *pgdat) +{ + enum zone_type j; + int nid = pgdat->node_id; + + pgdat_init_internals(pgdat); + pgdat->per_cpu_nodestats = &boot_nodestats; + + for (j = 0; j < MAX_NR_ZONES; j++) { + struct zone *zone = pgdat->node_zones + j; + unsigned long size, freesize, memmap_pages; + + size = zone->spanned_pages; + freesize = zone->present_pages; + + /* + * Adjust freesize so that it accounts for how much memory + * is used by this zone for memmap. This affects the watermark + * and per-cpu initialisations + */ + memmap_pages = calc_memmap_size(size, freesize); + if (!is_highmem_idx(j)) { + if (freesize >= memmap_pages) { + freesize -= memmap_pages; + if (memmap_pages) + pr_debug(" %s zone: %lu pages used for memmap\n", + zone_names[j], memmap_pages); + } else + pr_warn(" %s zone: %lu memmap pages exceeds freesize %lu\n", + zone_names[j], memmap_pages, freesize); + } + + /* Account for reserved pages */ + if (j == 0 && freesize > dma_reserve) { + freesize -= dma_reserve; + pr_debug(" %s zone: %lu pages reserved\n", zone_names[0], dma_reserve); + } + + if (!is_highmem_idx(j)) + nr_kernel_pages += freesize; + /* Charge for highmem memmap if there are enough kernel pages */ + else if (nr_kernel_pages > memmap_pages * 2) + nr_kernel_pages -= memmap_pages; + nr_all_pages += freesize; + + /* + * Set an approximate value for lowmem here, it will be adjusted + * when the bootmem allocator frees pages into the buddy system. + * And all highmem pages will be managed by the buddy system. + */ + zone_init_internals(zone, j, nid, freesize); + + if (!size) + continue; + + set_pageblock_order(); + setup_usemap(zone); + init_currently_empty_zone(zone, zone->zone_start_pfn, size); + } +} + +void __init *memmap_alloc(phys_addr_t size, phys_addr_t align, + phys_addr_t min_addr, int nid, bool exact_nid) +{ + void *ptr; + + if (exact_nid) + ptr = memblock_alloc_exact_nid_raw(size, align, min_addr, + MEMBLOCK_ALLOC_ACCESSIBLE, + nid); + else + ptr = memblock_alloc_try_nid_raw(size, align, min_addr, + MEMBLOCK_ALLOC_ACCESSIBLE, + nid); + + if (ptr && size > 0) + page_init_poison(ptr, size); + + return ptr; +} + +#ifdef CONFIG_FLATMEM +static void __init alloc_node_mem_map(struct pglist_data *pgdat) +{ + unsigned long __maybe_unused start = 0; + unsigned long __maybe_unused offset = 0; + + /* Skip empty nodes */ + if (!pgdat->node_spanned_pages) + return; + + start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1); + offset = pgdat->node_start_pfn - start; + /* ia64 gets its own node_mem_map, before this, without bootmem */ + if (!pgdat->node_mem_map) { + unsigned long size, end; + struct page *map; + + /* + * The zone's endpoints aren't required to be MAX_ORDER + * aligned but the node_mem_map endpoints must be in order + * for the buddy allocator to function correctly. + */ + end = pgdat_end_pfn(pgdat); + end = ALIGN(end, MAX_ORDER_NR_PAGES); + size = (end - start) * sizeof(struct page); + map = memmap_alloc(size, SMP_CACHE_BYTES, MEMBLOCK_LOW_LIMIT, + pgdat->node_id, false); + if (!map) + panic("Failed to allocate %ld bytes for node %d memory map\n", + size, pgdat->node_id); + pgdat->node_mem_map = map + offset; + } + pr_debug("%s: node %d, pgdat %08lx, node_mem_map %08lx\n", + __func__, pgdat->node_id, (unsigned long)pgdat, + (unsigned long)pgdat->node_mem_map); +#ifndef CONFIG_NUMA + /* + * With no DISCONTIG, the global mem_map is just set as node 0's + */ + if (pgdat == NODE_DATA(0)) { + mem_map = NODE_DATA(0)->node_mem_map; + if (page_to_pfn(mem_map) != pgdat->node_start_pfn) + mem_map -= offset; + } +#endif +} +#else +static inline void alloc_node_mem_map(struct pglist_data *pgdat) { } +#endif /* CONFIG_FLATMEM */ + +/** + * get_pfn_range_for_nid - Return the start and end page frames for a node + * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned. + * @start_pfn: Passed by reference. On return, it will have the node start_pfn. + * @end_pfn: Passed by reference. On return, it will have the node end_pfn. + * + * It returns the start and end page frame of a node based on information + * provided by memblock_set_node(). If called for a node + * with no available memory, a warning is printed and the start and end + * PFNs will be 0. + */ +void __init get_pfn_range_for_nid(unsigned int nid, + unsigned long *start_pfn, unsigned long *end_pfn) +{ + unsigned long this_start_pfn, this_end_pfn; + int i; + + *start_pfn = -1UL; + *end_pfn = 0; + + for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) { + *start_pfn = min(*start_pfn, this_start_pfn); + *end_pfn = max(*end_pfn, this_end_pfn); + } + + if (*start_pfn == -1UL) + *start_pfn = 0; +} + +static void __init free_area_init_node(int nid) +{ + pg_data_t *pgdat = NODE_DATA(nid); + unsigned long start_pfn = 0; + unsigned long end_pfn = 0; + + /* pg_data_t should be reset to zero when it's allocated */ + WARN_ON(pgdat->nr_zones || pgdat->kswapd_highest_zoneidx); + + get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); + + pgdat->node_id = nid; + pgdat->node_start_pfn = start_pfn; + pgdat->per_cpu_nodestats = NULL; + + if (start_pfn != end_pfn) { + pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid, + (u64)start_pfn << PAGE_SHIFT, + end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0); + } else { + pr_info("Initmem setup node %d as memoryless\n", nid); + } + + calculate_node_totalpages(pgdat, start_pfn, end_pfn); + + alloc_node_mem_map(pgdat); + pgdat_set_deferred_range(pgdat); + + free_area_init_core(pgdat); + lru_gen_init_pgdat(pgdat); +} + +/* Any regular or high memory on that node ? */ +static void check_for_memory(pg_data_t *pgdat, int nid) +{ + enum zone_type zone_type; + + for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) { + struct zone *zone = &pgdat->node_zones[zone_type]; + if (populated_zone(zone)) { + if (IS_ENABLED(CONFIG_HIGHMEM)) + node_set_state(nid, N_HIGH_MEMORY); + if (zone_type <= ZONE_NORMAL) + node_set_state(nid, N_NORMAL_MEMORY); + break; + } + } +} + +#if MAX_NUMNODES > 1 +/* + * Figure out the number of possible node ids. + */ +void __init setup_nr_node_ids(void) +{ + unsigned int highest; + + highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES); + nr_node_ids = highest + 1; +} +#endif + +static void __init free_area_init_memoryless_node(int nid) +{ + free_area_init_node(nid); +} + +/* + * Some architectures, e.g. ARC may have ZONE_HIGHMEM below ZONE_NORMAL. For + * such cases we allow max_zone_pfn sorted in the descending order + */ +bool __weak arch_has_descending_max_zone_pfns(void) +{ + return false; +} + +/** + * free_area_init - Initialise all pg_data_t and zone data + * @max_zone_pfn: an array of max PFNs for each zone + * + * This will call free_area_init_node() for each active node in the system. + * Using the page ranges provided by memblock_set_node(), the size of each + * zone in each node and their holes is calculated. If the maximum PFN + * between two adjacent zones match, it is assumed that the zone is empty. + * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed + * that arch_max_dma32_pfn has no pages. It is also assumed that a zone + * starts where the previous one ended. For example, ZONE_DMA32 starts + * at arch_max_dma_pfn. + */ +void __init free_area_init(unsigned long *max_zone_pfn) +{ + unsigned long start_pfn, end_pfn; + int i, nid, zone; + bool descending; + + /* Record where the zone boundaries are */ + memset(arch_zone_lowest_possible_pfn, 0, + sizeof(arch_zone_lowest_possible_pfn)); + memset(arch_zone_highest_possible_pfn, 0, + sizeof(arch_zone_highest_possible_pfn)); + + start_pfn = PHYS_PFN(memblock_start_of_DRAM()); + descending = arch_has_descending_max_zone_pfns(); + + for (i = 0; i < MAX_NR_ZONES; i++) { + if (descending) + zone = MAX_NR_ZONES - i - 1; + else + zone = i; + + if (zone == ZONE_MOVABLE) + continue; + + end_pfn = max(max_zone_pfn[zone], start_pfn); + arch_zone_lowest_possible_pfn[zone] = start_pfn; + arch_zone_highest_possible_pfn[zone] = end_pfn; + + start_pfn = end_pfn; + } + + /* Find the PFNs that ZONE_MOVABLE begins at in each node */ + memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn)); + find_zone_movable_pfns_for_nodes(); + + /* Print out the zone ranges */ + pr_info("Zone ranges:\n"); + for (i = 0; i < MAX_NR_ZONES; i++) { + if (i == ZONE_MOVABLE) + continue; + pr_info(" %-8s ", zone_names[i]); + if (arch_zone_lowest_possible_pfn[i] == + arch_zone_highest_possible_pfn[i]) + pr_cont("empty\n"); + else + pr_cont("[mem %#018Lx-%#018Lx]\n", + (u64)arch_zone_lowest_possible_pfn[i] + << PAGE_SHIFT, + ((u64)arch_zone_highest_possible_pfn[i] + << PAGE_SHIFT) - 1); + } + + /* Print out the PFNs ZONE_MOVABLE begins at in each node */ + pr_info("Movable zone start for each node\n"); + for (i = 0; i < MAX_NUMNODES; i++) { + if (zone_movable_pfn[i]) + pr_info(" Node %d: %#018Lx\n", i, + (u64)zone_movable_pfn[i] << PAGE_SHIFT); + } + + /* + * Print out the early node map, and initialize the + * subsection-map relative to active online memory ranges to + * enable future "sub-section" extensions of the memory map. + */ + pr_info("Early memory node ranges\n"); + for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { + pr_info(" node %3d: [mem %#018Lx-%#018Lx]\n", nid, + (u64)start_pfn << PAGE_SHIFT, + ((u64)end_pfn << PAGE_SHIFT) - 1); + subsection_map_init(start_pfn, end_pfn - start_pfn); + } + + /* Initialise every node */ + mminit_verify_pageflags_layout(); + setup_nr_node_ids(); + for_each_node(nid) { + pg_data_t *pgdat; + + if (!node_online(nid)) { + pr_info("Initializing node %d as memoryless\n", nid); + + /* Allocator not initialized yet */ + pgdat = arch_alloc_nodedata(nid); + if (!pgdat) + panic("Cannot allocate %zuB for node %d.\n", + sizeof(*pgdat), nid); + arch_refresh_nodedata(nid, pgdat); + free_area_init_memoryless_node(nid); + + /* + * We do not want to confuse userspace by sysfs + * files/directories for node without any memory + * attached to it, so this node is not marked as + * N_MEMORY and not marked online so that no sysfs + * hierarchy will be created via register_one_node for + * it. The pgdat will get fully initialized by + * hotadd_init_pgdat() when memory is hotplugged into + * this node. + */ + continue; + } + + pgdat = NODE_DATA(nid); + free_area_init_node(nid); + + /* Any memory on that node */ + if (pgdat->node_present_pages) + node_set_state(nid, N_MEMORY); + check_for_memory(pgdat, nid); + } + + memmap_init(); +} + +/** + * node_map_pfn_alignment - determine the maximum internode alignment + * + * This function should be called after node map is populated and sorted. + * It calculates the maximum power of two alignment which can distinguish + * all the nodes. + * + * For example, if all nodes are 1GiB and aligned to 1GiB, the return value + * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the + * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is + * shifted, 1GiB is enough and this function will indicate so. + * + * This is used to test whether pfn -> nid mapping of the chosen memory + * model has fine enough granularity to avoid incorrect mapping for the + * populated node map. + * + * Return: the determined alignment in pfn's. 0 if there is no alignment + * requirement (single node). + */ +unsigned long __init node_map_pfn_alignment(void) +{ + unsigned long accl_mask = 0, last_end = 0; + unsigned long start, end, mask; + int last_nid = NUMA_NO_NODE; + int i, nid; + + for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) { + if (!start || last_nid < 0 || last_nid == nid) { + last_nid = nid; + last_end = end; + continue; + } + + /* + * Start with a mask granular enough to pin-point to the + * start pfn and tick off bits one-by-one until it becomes + * too coarse to separate the current node from the last. + */ + mask = ~((1 << __ffs(start)) - 1); + while (mask && last_end <= (start & (mask << 1))) + mask <<= 1; + + /* accumulate all internode masks */ + accl_mask |= mask; + } + + /* convert mask to number of pages */ + return ~accl_mask + 1; +} + +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT +static void __init deferred_free_range(unsigned long pfn, + unsigned long nr_pages) +{ + struct page *page; + unsigned long i; + + if (!nr_pages) + return; + + page = pfn_to_page(pfn); + + /* Free a large naturally-aligned chunk if possible */ + if (nr_pages == pageblock_nr_pages && pageblock_aligned(pfn)) { + set_pageblock_migratetype(page, MIGRATE_MOVABLE); + __free_pages_core(page, pageblock_order); + return; + } + + for (i = 0; i < nr_pages; i++, page++, pfn++) { + if (pageblock_aligned(pfn)) + set_pageblock_migratetype(page, MIGRATE_MOVABLE); + __free_pages_core(page, 0); + } +} + +/* Completion tracking for deferred_init_memmap() threads */ +static atomic_t pgdat_init_n_undone __initdata; +static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp); + +static inline void __init pgdat_init_report_one_done(void) +{ + if (atomic_dec_and_test(&pgdat_init_n_undone)) + complete(&pgdat_init_all_done_comp); +} + +/* + * Returns true if page needs to be initialized or freed to buddy allocator. + * + * We check if a current large page is valid by only checking the validity + * of the head pfn. + */ +static inline bool __init deferred_pfn_valid(unsigned long pfn) +{ + if (pageblock_aligned(pfn) && !pfn_valid(pfn)) + return false; + return true; +} + +/* + * Free pages to buddy allocator. Try to free aligned pages in + * pageblock_nr_pages sizes. + */ +static void __init deferred_free_pages(unsigned long pfn, + unsigned long end_pfn) +{ + unsigned long nr_free = 0; + + for (; pfn < end_pfn; pfn++) { + if (!deferred_pfn_valid(pfn)) { + deferred_free_range(pfn - nr_free, nr_free); + nr_free = 0; + } else if (pageblock_aligned(pfn)) { + deferred_free_range(pfn - nr_free, nr_free); + nr_free = 1; + } else { + nr_free++; + } + } + /* Free the last block of pages to allocator */ + deferred_free_range(pfn - nr_free, nr_free); +} + +/* + * Initialize struct pages. We minimize pfn page lookups and scheduler checks + * by performing it only once every pageblock_nr_pages. + * Return number of pages initialized. + */ +static unsigned long __init deferred_init_pages(struct zone *zone, + unsigned long pfn, + unsigned long end_pfn) +{ + int nid = zone_to_nid(zone); + unsigned long nr_pages = 0; + int zid = zone_idx(zone); + struct page *page = NULL; + + for (; pfn < end_pfn; pfn++) { + if (!deferred_pfn_valid(pfn)) { + page = NULL; + continue; + } else if (!page || pageblock_aligned(pfn)) { + page = pfn_to_page(pfn); + } else { + page++; + } + __init_single_page(page, pfn, zid, nid); + nr_pages++; + } + return (nr_pages); +} + +/* + * This function is meant to pre-load the iterator for the zone init. + * Specifically it walks through the ranges until we are caught up to the + * first_init_pfn value and exits there. If we never encounter the value we + * return false indicating there are no valid ranges left. + */ +static bool __init +deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone, + unsigned long *spfn, unsigned long *epfn, + unsigned long first_init_pfn) +{ + u64 j; + + /* + * Start out by walking through the ranges in this zone that have + * already been initialized. We don't need to do anything with them + * so we just need to flush them out of the system. + */ + for_each_free_mem_pfn_range_in_zone(j, zone, spfn, epfn) { + if (*epfn <= first_init_pfn) + continue; + if (*spfn < first_init_pfn) + *spfn = first_init_pfn; + *i = j; + return true; + } + + return false; +} + +/* + * Initialize and free pages. We do it in two loops: first we initialize + * struct page, then free to buddy allocator, because while we are + * freeing pages we can access pages that are ahead (computing buddy + * page in __free_one_page()). + * + * In order to try and keep some memory in the cache we have the loop + * broken along max page order boundaries. This way we will not cause + * any issues with the buddy page computation. + */ +static unsigned long __init +deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn, + unsigned long *end_pfn) +{ + unsigned long mo_pfn = ALIGN(*start_pfn + 1, MAX_ORDER_NR_PAGES); + unsigned long spfn = *start_pfn, epfn = *end_pfn; + unsigned long nr_pages = 0; + u64 j = *i; + + /* First we loop through and initialize the page values */ + for_each_free_mem_pfn_range_in_zone_from(j, zone, start_pfn, end_pfn) { + unsigned long t; + + if (mo_pfn <= *start_pfn) + break; + + t = min(mo_pfn, *end_pfn); + nr_pages += deferred_init_pages(zone, *start_pfn, t); + + if (mo_pfn < *end_pfn) { + *start_pfn = mo_pfn; + break; + } + } + + /* Reset values and now loop through freeing pages as needed */ + swap(j, *i); + + for_each_free_mem_pfn_range_in_zone_from(j, zone, &spfn, &epfn) { + unsigned long t; + + if (mo_pfn <= spfn) + break; + + t = min(mo_pfn, epfn); + deferred_free_pages(spfn, t); + + if (mo_pfn <= epfn) + break; + } + + return nr_pages; +} + +static void __init +deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn, + void *arg) +{ + unsigned long spfn, epfn; + struct zone *zone = arg; + u64 i; + + deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, start_pfn); + + /* + * Initialize and free pages in MAX_ORDER sized increments so that we + * can avoid introducing any issues with the buddy allocator. + */ + while (spfn < end_pfn) { + deferred_init_maxorder(&i, zone, &spfn, &epfn); + cond_resched(); + } +} + +/* An arch may override for more concurrency. */ +__weak int __init +deferred_page_init_max_threads(const struct cpumask *node_cpumask) +{ + return 1; +} + +/* Initialise remaining memory on a node */ +static int __init deferred_init_memmap(void *data) +{ + pg_data_t *pgdat = data; + const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id); + unsigned long spfn = 0, epfn = 0; + unsigned long first_init_pfn, flags; + unsigned long start = jiffies; + struct zone *zone; + int zid, max_threads; + u64 i; + + /* Bind memory initialisation thread to a local node if possible */ + if (!cpumask_empty(cpumask)) + set_cpus_allowed_ptr(current, cpumask); + + pgdat_resize_lock(pgdat, &flags); + first_init_pfn = pgdat->first_deferred_pfn; + if (first_init_pfn == ULONG_MAX) { + pgdat_resize_unlock(pgdat, &flags); + pgdat_init_report_one_done(); + return 0; + } + + /* Sanity check boundaries */ + BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn); + BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat)); + pgdat->first_deferred_pfn = ULONG_MAX; + + /* + * Once we unlock here, the zone cannot be grown anymore, thus if an + * interrupt thread must allocate this early in boot, zone must be + * pre-grown prior to start of deferred page initialization. + */ + pgdat_resize_unlock(pgdat, &flags); + + /* Only the highest zone is deferred so find it */ + for (zid = 0; zid < MAX_NR_ZONES; zid++) { + zone = pgdat->node_zones + zid; + if (first_init_pfn < zone_end_pfn(zone)) + break; + } + + /* If the zone is empty somebody else may have cleared out the zone */ + if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, + first_init_pfn)) + goto zone_empty; + + max_threads = deferred_page_init_max_threads(cpumask); + + while (spfn < epfn) { + unsigned long epfn_align = ALIGN(epfn, PAGES_PER_SECTION); + struct padata_mt_job job = { + .thread_fn = deferred_init_memmap_chunk, + .fn_arg = zone, + .start = spfn, + .size = epfn_align - spfn, + .align = PAGES_PER_SECTION, + .min_chunk = PAGES_PER_SECTION, + .max_threads = max_threads, + }; + + padata_do_multithreaded(&job); + deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, + epfn_align); + } +zone_empty: + /* Sanity check that the next zone really is unpopulated */ + WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone)); + + pr_info("node %d deferred pages initialised in %ums\n", + pgdat->node_id, jiffies_to_msecs(jiffies - start)); + + pgdat_init_report_one_done(); + return 0; +} + +/* + * If this zone has deferred pages, try to grow it by initializing enough + * deferred pages to satisfy the allocation specified by order, rounded up to + * the nearest PAGES_PER_SECTION boundary. So we're adding memory in increments + * of SECTION_SIZE bytes by initializing struct pages in increments of + * PAGES_PER_SECTION * sizeof(struct page) bytes. + * + * Return true when zone was grown, otherwise return false. We return true even + * when we grow less than requested, to let the caller decide if there are + * enough pages to satisfy the allocation. + * + * Note: We use noinline because this function is needed only during boot, and + * it is called from a __ref function _deferred_grow_zone. This way we are + * making sure that it is not inlined into permanent text section. + */ +bool __init deferred_grow_zone(struct zone *zone, unsigned int order) +{ + unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION); + pg_data_t *pgdat = zone->zone_pgdat; + unsigned long first_deferred_pfn = pgdat->first_deferred_pfn; + unsigned long spfn, epfn, flags; + unsigned long nr_pages = 0; + u64 i; + + /* Only the last zone may have deferred pages */ + if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat)) + return false; + + pgdat_resize_lock(pgdat, &flags); + + /* + * If someone grew this zone while we were waiting for spinlock, return + * true, as there might be enough pages already. + */ + if (first_deferred_pfn != pgdat->first_deferred_pfn) { + pgdat_resize_unlock(pgdat, &flags); + return true; + } + + /* If the zone is empty somebody else may have cleared out the zone */ + if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, + first_deferred_pfn)) { + pgdat->first_deferred_pfn = ULONG_MAX; + pgdat_resize_unlock(pgdat, &flags); + /* Retry only once. */ + return first_deferred_pfn != ULONG_MAX; + } + + /* + * Initialize and free pages in MAX_ORDER sized increments so + * that we can avoid introducing any issues with the buddy + * allocator. + */ + while (spfn < epfn) { + /* update our first deferred PFN for this section */ + first_deferred_pfn = spfn; + + nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn); + touch_nmi_watchdog(); + + /* We should only stop along section boundaries */ + if ((first_deferred_pfn ^ spfn) < PAGES_PER_SECTION) + continue; + + /* If our quota has been met we can stop here */ + if (nr_pages >= nr_pages_needed) + break; + } + + pgdat->first_deferred_pfn = spfn; + pgdat_resize_unlock(pgdat, &flags); + + return nr_pages > 0; +} + +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ + +#ifdef CONFIG_CMA +void __init init_cma_reserved_pageblock(struct page *page) +{ + unsigned i = pageblock_nr_pages; + struct page *p = page; + + do { + __ClearPageReserved(p); + set_page_count(p, 0); + } while (++p, --i); + + set_pageblock_migratetype(page, MIGRATE_CMA); + set_page_refcounted(page); + __free_pages(page, pageblock_order); + + adjust_managed_page_count(page, pageblock_nr_pages); + page_zone(page)->cma_pages += pageblock_nr_pages; +} +#endif + +void __init page_alloc_init_late(void) +{ + struct zone *zone; + int nid; + +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT + + /* There will be num_node_state(N_MEMORY) threads */ + atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY)); + for_each_node_state(nid, N_MEMORY) { + kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid); + } + + /* Block until all are initialised */ + wait_for_completion(&pgdat_init_all_done_comp); + + /* + * We initialized the rest of the deferred pages. Permanently disable + * on-demand struct page initialization. + */ + static_branch_disable(&deferred_pages); + + /* Reinit limits that are based on free pages after the kernel is up */ + files_maxfiles_init(); +#endif + + buffer_init(); + + /* Discard memblock private memory */ + memblock_discard(); + + for_each_node_state(nid, N_MEMORY) + shuffle_free_memory(NODE_DATA(nid)); + + for_each_populated_zone(zone) + set_zone_contiguous(zone); +} + +#ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES +/* + * Returns the number of pages that arch has reserved but + * is not known to alloc_large_system_hash(). + */ +static unsigned long __init arch_reserved_kernel_pages(void) +{ + return 0; +} +#endif + +/* + * Adaptive scale is meant to reduce sizes of hash tables on large memory + * machines. As memory size is increased the scale is also increased but at + * slower pace. Starting from ADAPT_SCALE_BASE (64G), every time memory + * quadruples the scale is increased by one, which means the size of hash table + * only doubles, instead of quadrupling as well. + * Because 32-bit systems cannot have large physical memory, where this scaling + * makes sense, it is disabled on such platforms. + */ +#if __BITS_PER_LONG > 32 +#define ADAPT_SCALE_BASE (64ul << 30) +#define ADAPT_SCALE_SHIFT 2 +#define ADAPT_SCALE_NPAGES (ADAPT_SCALE_BASE >> PAGE_SHIFT) +#endif + +/* + * allocate a large system hash table from bootmem + * - it is assumed that the hash table must contain an exact power-of-2 + * quantity of entries + * - limit is the number of hash buckets, not the total allocation size + */ +void *__init alloc_large_system_hash(const char *tablename, + unsigned long bucketsize, + unsigned long numentries, + int scale, + int flags, + unsigned int *_hash_shift, + unsigned int *_hash_mask, + unsigned long low_limit, + unsigned long high_limit) +{ + unsigned long long max = high_limit; + unsigned long log2qty, size; + void *table; + gfp_t gfp_flags; + bool virt; + bool huge; + + /* allow the kernel cmdline to have a say */ + if (!numentries) { + /* round applicable memory size up to nearest megabyte */ + numentries = nr_kernel_pages; + numentries -= arch_reserved_kernel_pages(); + + /* It isn't necessary when PAGE_SIZE >= 1MB */ + if (PAGE_SIZE < SZ_1M) + numentries = round_up(numentries, SZ_1M / PAGE_SIZE); + +#if __BITS_PER_LONG > 32 + if (!high_limit) { + unsigned long adapt; + + for (adapt = ADAPT_SCALE_NPAGES; adapt < numentries; + adapt <<= ADAPT_SCALE_SHIFT) + scale++; + } +#endif + + /* limit to 1 bucket per 2^scale bytes of low memory */ + if (scale > PAGE_SHIFT) + numentries >>= (scale - PAGE_SHIFT); + else + numentries <<= (PAGE_SHIFT - scale); + + /* Make sure we've got at least a 0-order allocation.. */ + if (unlikely(flags & HASH_SMALL)) { + /* Makes no sense without HASH_EARLY */ + WARN_ON(!(flags & HASH_EARLY)); + if (!(numentries >> *_hash_shift)) { + numentries = 1UL << *_hash_shift; + BUG_ON(!numentries); + } + } else if (unlikely((numentries * bucketsize) < PAGE_SIZE)) + numentries = PAGE_SIZE / bucketsize; + } + numentries = roundup_pow_of_two(numentries); + + /* limit allocation size to 1/16 total memory by default */ + if (max == 0) { + max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; + do_div(max, bucketsize); + } + max = min(max, 0x80000000ULL); + + if (numentries < low_limit) + numentries = low_limit; + if (numentries > max) + numentries = max; + + log2qty = ilog2(numentries); + + gfp_flags = (flags & HASH_ZERO) ? GFP_ATOMIC | __GFP_ZERO : GFP_ATOMIC; + do { + virt = false; + size = bucketsize << log2qty; + if (flags & HASH_EARLY) { + if (flags & HASH_ZERO) + table = memblock_alloc(size, SMP_CACHE_BYTES); + else + table = memblock_alloc_raw(size, + SMP_CACHE_BYTES); + } else if (get_order(size) > MAX_ORDER || hashdist) { + table = vmalloc_huge(size, gfp_flags); + virt = true; + if (table) + huge = is_vm_area_hugepages(table); + } else { + /* + * If bucketsize is not a power-of-two, we may free + * some pages at the end of hash table which + * alloc_pages_exact() automatically does + */ + table = alloc_pages_exact(size, gfp_flags); + kmemleak_alloc(table, size, 1, gfp_flags); + } + } while (!table && size > PAGE_SIZE && --log2qty); + + if (!table) + panic("Failed to allocate %s hash table\n", tablename); + + pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n", + tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size, + virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear"); + + if (_hash_shift) + *_hash_shift = log2qty; + if (_hash_mask) + *_hash_mask = (1 << log2qty) - 1; + + return table; +} + +/** + * set_dma_reserve - set the specified number of pages reserved in the first zone + * @new_dma_reserve: The number of pages to mark reserved + * + * The per-cpu batchsize and zone watermarks are determined by managed_pages. + * In the DMA zone, a significant percentage may be consumed by kernel image + * and other unfreeable allocations which can skew the watermarks badly. This + * function may optionally be used to account for unfreeable pages in the + * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and + * smaller per-cpu batchsize. + */ +void __init set_dma_reserve(unsigned long new_dma_reserve) +{ + dma_reserve = new_dma_reserve; +} + +void __init memblock_free_pages(struct page *page, unsigned long pfn, + unsigned int order) +{ + if (!early_page_initialised(pfn)) + return; + if (!kmsan_memblock_free_pages(page, order)) { + /* KMSAN will take care of these pages. */ + return; + } + __free_pages_core(page, order); +} diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 33925488040f..8adc70b6034d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -72,9 +72,7 @@ #include #include #include -#include #include -#include #include #include #include @@ -355,7 +353,7 @@ int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES] = { [ZONE_MOVABLE] = 0, }; -static char * const zone_names[MAX_NR_ZONES] = { +char * const zone_names[MAX_NR_ZONES] = { #ifdef CONFIG_ZONE_DMA "DMA", #endif @@ -401,17 +399,6 @@ int user_min_free_kbytes = -1; int watermark_boost_factor __read_mostly = 15000; int watermark_scale_factor = 10; -static unsigned long nr_kernel_pages __initdata; -static unsigned long nr_all_pages __initdata; -static unsigned long dma_reserve __initdata; - -static unsigned long arch_zone_lowest_possible_pfn[MAX_NR_ZONES] __initdata; -static unsigned long arch_zone_highest_possible_pfn[MAX_NR_ZONES] __initdata; -static unsigned long required_kernelcore __initdata; -static unsigned long required_kernelcore_percent __initdata; -static unsigned long required_movablecore __initdata; -static unsigned long required_movablecore_percent __initdata; -static unsigned long zone_movable_pfn[MAX_NUMNODES] __initdata; bool mirrored_kernelcore __initdata_memblock; /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */ @@ -427,86 +414,36 @@ EXPORT_SYMBOL(nr_online_nodes); int page_group_by_mobility_disabled __read_mostly; -bool deferred_struct_pages __meminitdata; - #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT /* * During boot we initialize deferred pages on-demand, as needed, but once * page_alloc_init_late() has finished, the deferred pages are all initialized, * and we can permanently disable that path. */ -static DEFINE_STATIC_KEY_TRUE(deferred_pages); +DEFINE_STATIC_KEY_TRUE(deferred_pages); static inline bool deferred_pages_enabled(void) { return static_branch_unlikely(&deferred_pages); } -/* Returns true if the struct page for the pfn is initialised */ -static inline bool __meminit early_page_initialised(unsigned long pfn) -{ - int nid = early_pfn_to_nid(pfn); - - if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn) - return false; - - return true; -} - /* - * Returns true when the remaining initialisation should be deferred until - * later in the boot cycle when it can be parallelised. + * deferred_grow_zone() is __init, but it is called from + * get_page_from_freelist() during early boot until deferred_pages permanently + * disables this call. This is why we have refdata wrapper to avoid warning, + * and to ensure that the function body gets unloaded. */ -static bool __meminit -defer_init(int nid, unsigned long pfn, unsigned long end_pfn) +static bool __ref +_deferred_grow_zone(struct zone *zone, unsigned int order) { - static unsigned long prev_end_pfn, nr_initialised; - - if (early_page_ext_enabled()) - return false; - /* - * prev_end_pfn static that contains the end of previous zone - * No need to protect because called very early in boot before smp_init. - */ - if (prev_end_pfn != end_pfn) { - prev_end_pfn = end_pfn; - nr_initialised = 0; - } - - /* Always populate low zones for address-constrained allocations */ - if (end_pfn < pgdat_end_pfn(NODE_DATA(nid))) - return false; - - if (NODE_DATA(nid)->first_deferred_pfn != ULONG_MAX) - return true; - /* - * We start only with one section of pages, more pages are added as - * needed until the rest of deferred pages are initialized. - */ - nr_initialised++; - if ((nr_initialised > PAGES_PER_SECTION) && - (pfn & (PAGES_PER_SECTION - 1)) == 0) { - NODE_DATA(nid)->first_deferred_pfn = pfn; - return true; - } - return false; + return deferred_grow_zone(zone, order); } #else static inline bool deferred_pages_enabled(void) { return false; } - -static inline bool early_page_initialised(unsigned long pfn) -{ - return true; -} - -static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn) -{ - return false; -} -#endif +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ /* Return a pointer to the bitmap storing bits affecting a block of pages */ static inline unsigned long *get_pageblock_bitmap(const struct page *page, @@ -772,26 +709,6 @@ void free_compound_page(struct page *page) free_the_page(page, compound_order(page)); } -static void prep_compound_head(struct page *page, unsigned int order) -{ - struct folio *folio = (struct folio *)page; - - set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); - set_compound_order(page, order); - atomic_set(&folio->_entire_mapcount, -1); - atomic_set(&folio->_nr_pages_mapped, 0); - atomic_set(&folio->_pincount, 0); -} - -static void prep_compound_tail(struct page *head, int tail_idx) -{ - struct page *p = head + tail_idx; - - p->mapping = TAIL_MAPPING; - set_compound_head(p, head); - set_page_private(p, 0); -} - void prep_compound_page(struct page *page, unsigned int order) { int i; @@ -1608,80 +1525,6 @@ static void free_one_page(struct zone *zone, spin_unlock_irqrestore(&zone->lock, flags); } -static void __meminit __init_single_page(struct page *page, unsigned long pfn, - unsigned long zone, int nid) -{ - mm_zero_struct_page(page); - set_page_links(page, zone, nid, pfn); - init_page_count(page); - page_mapcount_reset(page); - page_cpupid_reset_last(page); - page_kasan_tag_reset(page); - - INIT_LIST_HEAD(&page->lru); -#ifdef WANT_PAGE_VIRTUAL - /* The shift won't overflow because ZONE_NORMAL is below 4G. */ - if (!is_highmem_idx(zone)) - set_page_address(page, __va(pfn << PAGE_SHIFT)); -#endif -} - -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT -static void __meminit init_reserved_page(unsigned long pfn) -{ - pg_data_t *pgdat; - int nid, zid; - - if (early_page_initialised(pfn)) - return; - - nid = early_pfn_to_nid(pfn); - pgdat = NODE_DATA(nid); - - for (zid = 0; zid < MAX_NR_ZONES; zid++) { - struct zone *zone = &pgdat->node_zones[zid]; - - if (zone_spans_pfn(zone, pfn)) - break; - } - __init_single_page(pfn_to_page(pfn), pfn, zid, nid); -} -#else -static inline void init_reserved_page(unsigned long pfn) -{ -} -#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ - -/* - * Initialised pages do not have PageReserved set. This function is - * called for each range allocated by the bootmem allocator and - * marks the pages PageReserved. The remaining valid pages are later - * sent to the buddy page allocator. - */ -void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end) -{ - unsigned long start_pfn = PFN_DOWN(start); - unsigned long end_pfn = PFN_UP(end); - - for (; start_pfn < end_pfn; start_pfn++) { - if (pfn_valid(start_pfn)) { - struct page *page = pfn_to_page(start_pfn); - - init_reserved_page(start_pfn); - - /* Avoid false-positive PageTail() */ - INIT_LIST_HEAD(&page->lru); - - /* - * no need for atomic set_bit because the struct - * page is not visible yet so nobody should - * access it yet. - */ - __SetPageReserved(page); - } - } -} - static void __free_pages_ok(struct page *page, unsigned int order, fpi_t fpi_flags) { @@ -1740,70 +1583,6 @@ void __free_pages_core(struct page *page, unsigned int order) __free_pages_ok(page, order, FPI_TO_TAIL); } -#ifdef CONFIG_NUMA - -/* - * During memory init memblocks map pfns to nids. The search is expensive and - * this caches recent lookups. The implementation of __early_pfn_to_nid - * treats start/end as pfns. - */ -struct mminit_pfnnid_cache { - unsigned long last_start; - unsigned long last_end; - int last_nid; -}; - -static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata; - -/* - * Required by SPARSEMEM. Given a PFN, return what node the PFN is on. - */ -static int __meminit __early_pfn_to_nid(unsigned long pfn, - struct mminit_pfnnid_cache *state) -{ - unsigned long start_pfn, end_pfn; - int nid; - - if (state->last_start <= pfn && pfn < state->last_end) - return state->last_nid; - - nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn); - if (nid != NUMA_NO_NODE) { - state->last_start = start_pfn; - state->last_end = end_pfn; - state->last_nid = nid; - } - - return nid; -} - -int __meminit early_pfn_to_nid(unsigned long pfn) -{ - static DEFINE_SPINLOCK(early_pfn_lock); - int nid; - - spin_lock(&early_pfn_lock); - nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache); - if (nid < 0) - nid = first_online_node; - spin_unlock(&early_pfn_lock); - - return nid; -} -#endif /* CONFIG_NUMA */ - -void __init memblock_free_pages(struct page *page, unsigned long pfn, - unsigned int order) -{ - if (!early_page_initialised(pfn)) - return; - if (!kmsan_memblock_free_pages(page, order)) { - /* KMSAN will take care of these pages. */ - return; - } - __free_pages_core(page, order); -} - /* * Check that the whole (or subset of) a pageblock given by the interval of * [start_pfn, end_pfn) is valid and within the same zone, before scanning it @@ -1874,570 +1653,131 @@ void clear_zone_contiguous(struct zone *zone) zone->contiguous = false; } -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT -static void __init deferred_free_range(unsigned long pfn, - unsigned long nr_pages) -{ - struct page *page; - unsigned long i; - - if (!nr_pages) - return; - - page = pfn_to_page(pfn); - - /* Free a large naturally-aligned chunk if possible */ - if (nr_pages == pageblock_nr_pages && pageblock_aligned(pfn)) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - __free_pages_core(page, pageblock_order); - return; - } - - for (i = 0; i < nr_pages; i++, page++, pfn++) { - if (pageblock_aligned(pfn)) - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - __free_pages_core(page, 0); - } -} - -/* Completion tracking for deferred_init_memmap() threads */ -static atomic_t pgdat_init_n_undone __initdata; -static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp); - -static inline void __init pgdat_init_report_one_done(void) -{ - if (atomic_dec_and_test(&pgdat_init_n_undone)) - complete(&pgdat_init_all_done_comp); -} - /* - * Returns true if page needs to be initialized or freed to buddy allocator. + * The order of subdivision here is critical for the IO subsystem. + * Please do not alter this order without good reasons and regression + * testing. Specifically, as large blocks of memory are subdivided, + * the order in which smaller blocks are delivered depends on the order + * they're subdivided in this function. This is the primary factor + * influencing the order in which pages are delivered to the IO + * subsystem according to empirical testing, and this is also justified + * by considering the behavior of a buddy system containing a single + * large block of memory acted on by a series of small allocations. + * This behavior is a critical factor in sglist merging's success. * - * We check if a current large page is valid by only checking the validity - * of the head pfn. + * -- nyc */ -static inline bool __init deferred_pfn_valid(unsigned long pfn) +static inline void expand(struct zone *zone, struct page *page, + int low, int high, int migratetype) { - if (pageblock_aligned(pfn) && !pfn_valid(pfn)) - return false; - return true; -} - -/* - * Free pages to buddy allocator. Try to free aligned pages in - * pageblock_nr_pages sizes. - */ -static void __init deferred_free_pages(unsigned long pfn, - unsigned long end_pfn) -{ - unsigned long nr_free = 0; - - for (; pfn < end_pfn; pfn++) { - if (!deferred_pfn_valid(pfn)) { - deferred_free_range(pfn - nr_free, nr_free); - nr_free = 0; - } else if (pageblock_aligned(pfn)) { - deferred_free_range(pfn - nr_free, nr_free); - nr_free = 1; - } else { - nr_free++; - } - } - /* Free the last block of pages to allocator */ - deferred_free_range(pfn - nr_free, nr_free); -} + unsigned long size = 1 << high; -/* - * Initialize struct pages. We minimize pfn page lookups and scheduler checks - * by performing it only once every pageblock_nr_pages. - * Return number of pages initialized. - */ -static unsigned long __init deferred_init_pages(struct zone *zone, - unsigned long pfn, - unsigned long end_pfn) -{ - int nid = zone_to_nid(zone); - unsigned long nr_pages = 0; - int zid = zone_idx(zone); - struct page *page = NULL; + while (high > low) { + high--; + size >>= 1; + VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]); - for (; pfn < end_pfn; pfn++) { - if (!deferred_pfn_valid(pfn)) { - page = NULL; + /* + * Mark as guard pages (or page), that will allow to + * merge back to allocator when buddy will be freed. + * Corresponding page table entries will not be touched, + * pages will stay not present in virtual address space + */ + if (set_page_guard(zone, &page[size], high, migratetype)) continue; - } else if (!page || pageblock_aligned(pfn)) { - page = pfn_to_page(pfn); - } else { - page++; - } - __init_single_page(page, pfn, zid, nid); - nr_pages++; + + add_to_free_list(&page[size], zone, high, migratetype); + set_buddy_order(&page[size], high); } - return (nr_pages); } -/* - * This function is meant to pre-load the iterator for the zone init. - * Specifically it walks through the ranges until we are caught up to the - * first_init_pfn value and exits there. If we never encounter the value we - * return false indicating there are no valid ranges left. - */ -static bool __init -deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone, - unsigned long *spfn, unsigned long *epfn, - unsigned long first_init_pfn) +static void check_new_page_bad(struct page *page) { - u64 j; - - /* - * Start out by walking through the ranges in this zone that have - * already been initialized. We don't need to do anything with them - * so we just need to flush them out of the system. - */ - for_each_free_mem_pfn_range_in_zone(j, zone, spfn, epfn) { - if (*epfn <= first_init_pfn) - continue; - if (*spfn < first_init_pfn) - *spfn = first_init_pfn; - *i = j; - return true; + if (unlikely(page->flags & __PG_HWPOISON)) { + /* Don't complain about hwpoisoned pages */ + page_mapcount_reset(page); /* remove PageBuddy */ + return; } - return false; + bad_page(page, + page_bad_reason(page, PAGE_FLAGS_CHECK_AT_PREP)); } /* - * Initialize and free pages. We do it in two loops: first we initialize - * struct page, then free to buddy allocator, because while we are - * freeing pages we can access pages that are ahead (computing buddy - * page in __free_one_page()). - * - * In order to try and keep some memory in the cache we have the loop - * broken along max page order boundaries. This way we will not cause - * any issues with the buddy page computation. + * This page is about to be returned from the page allocator */ -static unsigned long __init -deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn, - unsigned long *end_pfn) +static int check_new_page(struct page *page) { - unsigned long mo_pfn = ALIGN(*start_pfn + 1, MAX_ORDER_NR_PAGES); - unsigned long spfn = *start_pfn, epfn = *end_pfn; - unsigned long nr_pages = 0; - u64 j = *i; - - /* First we loop through and initialize the page values */ - for_each_free_mem_pfn_range_in_zone_from(j, zone, start_pfn, end_pfn) { - unsigned long t; + if (likely(page_expected_state(page, + PAGE_FLAGS_CHECK_AT_PREP|__PG_HWPOISON))) + return 0; - if (mo_pfn <= *start_pfn) - break; + check_new_page_bad(page); + return 1; +} - t = min(mo_pfn, *end_pfn); - nr_pages += deferred_init_pages(zone, *start_pfn, t); +static inline bool check_new_pages(struct page *page, unsigned int order) +{ + if (is_check_pages_enabled()) { + for (int i = 0; i < (1 << order); i++) { + struct page *p = page + i; - if (mo_pfn < *end_pfn) { - *start_pfn = mo_pfn; - break; + if (unlikely(check_new_page(p))) + return true; } } - /* Reset values and now loop through freeing pages as needed */ - swap(j, *i); - - for_each_free_mem_pfn_range_in_zone_from(j, zone, &spfn, &epfn) { - unsigned long t; - - if (mo_pfn <= spfn) - break; - - t = min(mo_pfn, epfn); - deferred_free_pages(spfn, t); - - if (mo_pfn <= epfn) - break; - } - - return nr_pages; + return false; } -static void __init -deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn, - void *arg) +static inline bool should_skip_kasan_unpoison(gfp_t flags) { - unsigned long spfn, epfn; - struct zone *zone = arg; - u64 i; + /* Don't skip if a software KASAN mode is enabled. */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC) || + IS_ENABLED(CONFIG_KASAN_SW_TAGS)) + return false; - deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, start_pfn); + /* Skip, if hardware tag-based KASAN is not enabled. */ + if (!kasan_hw_tags_enabled()) + return true; /* - * Initialize and free pages in MAX_ORDER sized increments so that we - * can avoid introducing any issues with the buddy allocator. + * With hardware tag-based KASAN enabled, skip if this has been + * requested via __GFP_SKIP_KASAN. */ - while (spfn < end_pfn) { - deferred_init_maxorder(&i, zone, &spfn, &epfn); - cond_resched(); - } + return flags & __GFP_SKIP_KASAN; } -/* An arch may override for more concurrency. */ -__weak int __init -deferred_page_init_max_threads(const struct cpumask *node_cpumask) +static inline bool should_skip_init(gfp_t flags) { - return 1; + /* Don't skip, if hardware tag-based KASAN is not enabled. */ + if (!kasan_hw_tags_enabled()) + return false; + + /* For hardware tag-based KASAN, skip if requested. */ + return (flags & __GFP_SKIP_ZERO); } -/* Initialise remaining memory on a node */ -static int __init deferred_init_memmap(void *data) +inline void post_alloc_hook(struct page *page, unsigned int order, + gfp_t gfp_flags) { - pg_data_t *pgdat = data; - const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id); - unsigned long spfn = 0, epfn = 0; - unsigned long first_init_pfn, flags; - unsigned long start = jiffies; - struct zone *zone; - int zid, max_threads; - u64 i; - - /* Bind memory initialisation thread to a local node if possible */ - if (!cpumask_empty(cpumask)) - set_cpus_allowed_ptr(current, cpumask); - - pgdat_resize_lock(pgdat, &flags); - first_init_pfn = pgdat->first_deferred_pfn; - if (first_init_pfn == ULONG_MAX) { - pgdat_resize_unlock(pgdat, &flags); - pgdat_init_report_one_done(); - return 0; - } + bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags) && + !should_skip_init(gfp_flags); + bool zero_tags = init && (gfp_flags & __GFP_ZEROTAGS); + int i; + + set_page_private(page, 0); + set_page_refcounted(page); - /* Sanity check boundaries */ - BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn); - BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat)); - pgdat->first_deferred_pfn = ULONG_MAX; + arch_alloc_page(page, order); + debug_pagealloc_map_pages(page, 1 << order); /* - * Once we unlock here, the zone cannot be grown anymore, thus if an - * interrupt thread must allocate this early in boot, zone must be - * pre-grown prior to start of deferred page initialization. + * Page unpoisoning must happen before memory initialization. + * Otherwise, the poison pattern will be overwritten for __GFP_ZERO + * allocations and the page unpoisoning code will complain. */ - pgdat_resize_unlock(pgdat, &flags); - - /* Only the highest zone is deferred so find it */ - for (zid = 0; zid < MAX_NR_ZONES; zid++) { - zone = pgdat->node_zones + zid; - if (first_init_pfn < zone_end_pfn(zone)) - break; - } - - /* If the zone is empty somebody else may have cleared out the zone */ - if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, - first_init_pfn)) - goto zone_empty; - - max_threads = deferred_page_init_max_threads(cpumask); - - while (spfn < epfn) { - unsigned long epfn_align = ALIGN(epfn, PAGES_PER_SECTION); - struct padata_mt_job job = { - .thread_fn = deferred_init_memmap_chunk, - .fn_arg = zone, - .start = spfn, - .size = epfn_align - spfn, - .align = PAGES_PER_SECTION, - .min_chunk = PAGES_PER_SECTION, - .max_threads = max_threads, - }; - - padata_do_multithreaded(&job); - deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, - epfn_align); - } -zone_empty: - /* Sanity check that the next zone really is unpopulated */ - WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone)); - - pr_info("node %d deferred pages initialised in %ums\n", - pgdat->node_id, jiffies_to_msecs(jiffies - start)); - - pgdat_init_report_one_done(); - return 0; -} - -/* - * If this zone has deferred pages, try to grow it by initializing enough - * deferred pages to satisfy the allocation specified by order, rounded up to - * the nearest PAGES_PER_SECTION boundary. So we're adding memory in increments - * of SECTION_SIZE bytes by initializing struct pages in increments of - * PAGES_PER_SECTION * sizeof(struct page) bytes. - * - * Return true when zone was grown, otherwise return false. We return true even - * when we grow less than requested, to let the caller decide if there are - * enough pages to satisfy the allocation. - * - * Note: We use noinline because this function is needed only during boot, and - * it is called from a __ref function _deferred_grow_zone. This way we are - * making sure that it is not inlined into permanent text section. - */ -static noinline bool __init -deferred_grow_zone(struct zone *zone, unsigned int order) -{ - unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION); - pg_data_t *pgdat = zone->zone_pgdat; - unsigned long first_deferred_pfn = pgdat->first_deferred_pfn; - unsigned long spfn, epfn, flags; - unsigned long nr_pages = 0; - u64 i; - - /* Only the last zone may have deferred pages */ - if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat)) - return false; - - pgdat_resize_lock(pgdat, &flags); - - /* - * If someone grew this zone while we were waiting for spinlock, return - * true, as there might be enough pages already. - */ - if (first_deferred_pfn != pgdat->first_deferred_pfn) { - pgdat_resize_unlock(pgdat, &flags); - return true; - } - - /* If the zone is empty somebody else may have cleared out the zone */ - if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, - first_deferred_pfn)) { - pgdat->first_deferred_pfn = ULONG_MAX; - pgdat_resize_unlock(pgdat, &flags); - /* Retry only once. */ - return first_deferred_pfn != ULONG_MAX; - } - - /* - * Initialize and free pages in MAX_ORDER sized increments so - * that we can avoid introducing any issues with the buddy - * allocator. - */ - while (spfn < epfn) { - /* update our first deferred PFN for this section */ - first_deferred_pfn = spfn; - - nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn); - touch_nmi_watchdog(); - - /* We should only stop along section boundaries */ - if ((first_deferred_pfn ^ spfn) < PAGES_PER_SECTION) - continue; - - /* If our quota has been met we can stop here */ - if (nr_pages >= nr_pages_needed) - break; - } - - pgdat->first_deferred_pfn = spfn; - pgdat_resize_unlock(pgdat, &flags); - - return nr_pages > 0; -} - -/* - * deferred_grow_zone() is __init, but it is called from - * get_page_from_freelist() during early boot until deferred_pages permanently - * disables this call. This is why we have refdata wrapper to avoid warning, - * and to ensure that the function body gets unloaded. - */ -static bool __ref -_deferred_grow_zone(struct zone *zone, unsigned int order) -{ - return deferred_grow_zone(zone, order); -} - -#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ - -void __init page_alloc_init_late(void) -{ - struct zone *zone; - int nid; - -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT - - /* There will be num_node_state(N_MEMORY) threads */ - atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY)); - for_each_node_state(nid, N_MEMORY) { - kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid); - } - - /* Block until all are initialised */ - wait_for_completion(&pgdat_init_all_done_comp); - - /* - * We initialized the rest of the deferred pages. Permanently disable - * on-demand struct page initialization. - */ - static_branch_disable(&deferred_pages); - - /* Reinit limits that are based on free pages after the kernel is up */ - files_maxfiles_init(); -#endif - - buffer_init(); - - /* Discard memblock private memory */ - memblock_discard(); - - for_each_node_state(nid, N_MEMORY) - shuffle_free_memory(NODE_DATA(nid)); - - for_each_populated_zone(zone) - set_zone_contiguous(zone); -} - -#ifdef CONFIG_CMA -/* Free whole pageblock and set its migration type to MIGRATE_CMA. */ -void __init init_cma_reserved_pageblock(struct page *page) -{ - unsigned i = pageblock_nr_pages; - struct page *p = page; - - do { - __ClearPageReserved(p); - set_page_count(p, 0); - } while (++p, --i); - - set_pageblock_migratetype(page, MIGRATE_CMA); - set_page_refcounted(page); - __free_pages(page, pageblock_order); - - adjust_managed_page_count(page, pageblock_nr_pages); - page_zone(page)->cma_pages += pageblock_nr_pages; -} -#endif - -/* - * The order of subdivision here is critical for the IO subsystem. - * Please do not alter this order without good reasons and regression - * testing. Specifically, as large blocks of memory are subdivided, - * the order in which smaller blocks are delivered depends on the order - * they're subdivided in this function. This is the primary factor - * influencing the order in which pages are delivered to the IO - * subsystem according to empirical testing, and this is also justified - * by considering the behavior of a buddy system containing a single - * large block of memory acted on by a series of small allocations. - * This behavior is a critical factor in sglist merging's success. - * - * -- nyc - */ -static inline void expand(struct zone *zone, struct page *page, - int low, int high, int migratetype) -{ - unsigned long size = 1 << high; - - while (high > low) { - high--; - size >>= 1; - VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]); - - /* - * Mark as guard pages (or page), that will allow to - * merge back to allocator when buddy will be freed. - * Corresponding page table entries will not be touched, - * pages will stay not present in virtual address space - */ - if (set_page_guard(zone, &page[size], high, migratetype)) - continue; - - add_to_free_list(&page[size], zone, high, migratetype); - set_buddy_order(&page[size], high); - } -} - -static void check_new_page_bad(struct page *page) -{ - if (unlikely(page->flags & __PG_HWPOISON)) { - /* Don't complain about hwpoisoned pages */ - page_mapcount_reset(page); /* remove PageBuddy */ - return; - } - - bad_page(page, - page_bad_reason(page, PAGE_FLAGS_CHECK_AT_PREP)); -} - -/* - * This page is about to be returned from the page allocator - */ -static int check_new_page(struct page *page) -{ - if (likely(page_expected_state(page, - PAGE_FLAGS_CHECK_AT_PREP|__PG_HWPOISON))) - return 0; - - check_new_page_bad(page); - return 1; -} - -static inline bool check_new_pages(struct page *page, unsigned int order) -{ - if (is_check_pages_enabled()) { - for (int i = 0; i < (1 << order); i++) { - struct page *p = page + i; - - if (unlikely(check_new_page(p))) - return true; - } - } - - return false; -} - -static inline bool should_skip_kasan_unpoison(gfp_t flags) -{ - /* Don't skip if a software KASAN mode is enabled. */ - if (IS_ENABLED(CONFIG_KASAN_GENERIC) || - IS_ENABLED(CONFIG_KASAN_SW_TAGS)) - return false; - - /* Skip, if hardware tag-based KASAN is not enabled. */ - if (!kasan_hw_tags_enabled()) - return true; - - /* - * With hardware tag-based KASAN enabled, skip if this has been - * requested via __GFP_SKIP_KASAN. - */ - return flags & __GFP_SKIP_KASAN; -} - -static inline bool should_skip_init(gfp_t flags) -{ - /* Don't skip, if hardware tag-based KASAN is not enabled. */ - if (!kasan_hw_tags_enabled()) - return false; - - /* For hardware tag-based KASAN, skip if requested. */ - return (flags & __GFP_SKIP_ZERO); -} - -inline void post_alloc_hook(struct page *page, unsigned int order, - gfp_t gfp_flags) -{ - bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags) && - !should_skip_init(gfp_flags); - bool zero_tags = init && (gfp_flags & __GFP_ZEROTAGS); - int i; - - set_page_private(page, 0); - set_page_refcounted(page); - - arch_alloc_page(page, order); - debug_pagealloc_map_pages(page, 1 << order); - - /* - * Page unpoisoning must happen before memory initialization. - * Otherwise, the poison pattern will be overwritten for __GFP_ZERO - * allocations and the page unpoisoning code will complain. - */ - kernel_unpoison_pages(page, 1 << order); + kernel_unpoison_pages(page, 1 << order); /* * As memory initialization might be integrated into KASAN, @@ -6547,7 +5887,6 @@ static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonesta #define BOOT_PAGESET_BATCH 1 static DEFINE_PER_CPU(struct per_cpu_pages, boot_pageset); static DEFINE_PER_CPU(struct per_cpu_zonestat, boot_zonestats); -static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); static void __build_all_zonelists(void *data) { @@ -6661,395 +6000,35 @@ void __ref build_all_zonelists(pg_data_t *pgdat) #endif } -/* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */ -static bool __meminit -overlap_memmap_init(unsigned long zone, unsigned long *pfn) -{ - static struct memblock_region *r; - - if (mirrored_kernelcore && zone == ZONE_MOVABLE) { - if (!r || *pfn >= memblock_region_memory_end_pfn(r)) { - for_each_mem_region(r) { - if (*pfn < memblock_region_memory_end_pfn(r)) - break; - } - } - if (*pfn >= memblock_region_memory_base_pfn(r) && - memblock_is_mirror(r)) { - *pfn = memblock_region_memory_end_pfn(r); - return true; - } - } - return false; -} - -/* - * Initially all pages are reserved - free ones are freed - * up by memblock_free_all() once the early boot process is - * done. Non-atomic initialization, single-pass. - * - * All aligned pageblocks are initialized to the specified migratetype - * (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related - * zone stats (e.g., nr_isolate_pageblock) are touched. - */ -void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone, - unsigned long start_pfn, unsigned long zone_end_pfn, - enum meminit_context context, - struct vmem_altmap *altmap, int migratetype) +static int zone_batchsize(struct zone *zone) { - unsigned long pfn, end_pfn = start_pfn + size; - struct page *page; +#ifdef CONFIG_MMU + int batch; - if (highest_memmap_pfn < end_pfn - 1) - highest_memmap_pfn = end_pfn - 1; + /* + * The number of pages to batch allocate is either ~0.1% + * of the zone or 1MB, whichever is smaller. The batch + * size is striking a balance between allocation latency + * and zone lock contention. + */ + batch = min(zone_managed_pages(zone) >> 10, SZ_1M / PAGE_SIZE); + batch /= 4; /* We effectively *= 4 below */ + if (batch < 1) + batch = 1; -#ifdef CONFIG_ZONE_DEVICE /* - * Honor reservation requested by the driver for this ZONE_DEVICE - * memory. We limit the total number of pages to initialize to just - * those that might contain the memory mapping. We will defer the - * ZONE_DEVICE page initialization until after we have released - * the hotplug lock. + * Clamp the batch to a 2^n - 1 value. Having a power + * of 2 value was found to be more likely to have + * suboptimal cache aliasing properties in some cases. + * + * For example if 2 tasks are alternately allocating + * batches of pages, one task can end up with a lot + * of pages of one half of the possible page colors + * and the other with pages of the other colors. */ - if (zone == ZONE_DEVICE) { - if (!altmap) - return; + batch = rounddown_pow_of_two(batch + batch/2) - 1; - if (start_pfn == altmap->base_pfn) - start_pfn += altmap->reserve; - end_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); - } -#endif - - for (pfn = start_pfn; pfn < end_pfn; ) { - /* - * There can be holes in boot-time mem_map[]s handed to this - * function. They do not exist on hotplugged memory. - */ - if (context == MEMINIT_EARLY) { - if (overlap_memmap_init(zone, &pfn)) - continue; - if (defer_init(nid, pfn, zone_end_pfn)) { - deferred_struct_pages = true; - break; - } - } - - page = pfn_to_page(pfn); - __init_single_page(page, pfn, zone, nid); - if (context == MEMINIT_HOTPLUG) - __SetPageReserved(page); - - /* - * Usually, we want to mark the pageblock MIGRATE_MOVABLE, - * such that unmovable allocations won't be scattered all - * over the place during system boot. - */ - if (pageblock_aligned(pfn)) { - set_pageblock_migratetype(page, migratetype); - cond_resched(); - } - pfn++; - } -} - -#ifdef CONFIG_ZONE_DEVICE -static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, - unsigned long zone_idx, int nid, - struct dev_pagemap *pgmap) -{ - - __init_single_page(page, pfn, zone_idx, nid); - - /* - * Mark page reserved as it will need to wait for onlining - * phase for it to be fully associated with a zone. - * - * We can use the non-atomic __set_bit operation for setting - * the flag as we are still initializing the pages. - */ - __SetPageReserved(page); - - /* - * ZONE_DEVICE pages union ->lru with a ->pgmap back pointer - * and zone_device_data. It is a bug if a ZONE_DEVICE page is - * ever freed or placed on a driver-private list. - */ - page->pgmap = pgmap; - page->zone_device_data = NULL; - - /* - * Mark the block movable so that blocks are reserved for - * movable at startup. This will force kernel allocations - * to reserve their blocks rather than leaking throughout - * the address space during boot when many long-lived - * kernel allocations are made. - * - * Please note that MEMINIT_HOTPLUG path doesn't clear memmap - * because this is done early in section_activate() - */ - if (pageblock_aligned(pfn)) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - cond_resched(); - } - - /* - * ZONE_DEVICE pages are released directly to the driver page allocator - * which will set the page count to 1 when allocating the page. - */ - if (pgmap->type == MEMORY_DEVICE_PRIVATE || - pgmap->type == MEMORY_DEVICE_COHERENT) - set_page_count(page, 0); -} - -/* - * With compound page geometry and when struct pages are stored in ram most - * tail pages are reused. Consequently, the amount of unique struct pages to - * initialize is a lot smaller that the total amount of struct pages being - * mapped. This is a paired / mild layering violation with explicit knowledge - * of how the sparse_vmemmap internals handle compound pages in the lack - * of an altmap. See vmemmap_populate_compound_pages(). - */ -static inline unsigned long compound_nr_pages(struct vmem_altmap *altmap, - unsigned long nr_pages) -{ - return is_power_of_2(sizeof(struct page)) && - !altmap ? 2 * (PAGE_SIZE / sizeof(struct page)) : nr_pages; -} - -static void __ref memmap_init_compound(struct page *head, - unsigned long head_pfn, - unsigned long zone_idx, int nid, - struct dev_pagemap *pgmap, - unsigned long nr_pages) -{ - unsigned long pfn, end_pfn = head_pfn + nr_pages; - unsigned int order = pgmap->vmemmap_shift; - - __SetPageHead(head); - for (pfn = head_pfn + 1; pfn < end_pfn; pfn++) { - struct page *page = pfn_to_page(pfn); - - __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); - prep_compound_tail(head, pfn - head_pfn); - set_page_count(page, 0); - - /* - * The first tail page stores important compound page info. - * Call prep_compound_head() after the first tail page has - * been initialized, to not have the data overwritten. - */ - if (pfn == head_pfn + 1) - prep_compound_head(head, order); - } -} - -void __ref memmap_init_zone_device(struct zone *zone, - unsigned long start_pfn, - unsigned long nr_pages, - struct dev_pagemap *pgmap) -{ - unsigned long pfn, end_pfn = start_pfn + nr_pages; - struct pglist_data *pgdat = zone->zone_pgdat; - struct vmem_altmap *altmap = pgmap_altmap(pgmap); - unsigned int pfns_per_compound = pgmap_vmemmap_nr(pgmap); - unsigned long zone_idx = zone_idx(zone); - unsigned long start = jiffies; - int nid = pgdat->node_id; - - if (WARN_ON_ONCE(!pgmap || zone_idx != ZONE_DEVICE)) - return; - - /* - * The call to memmap_init should have already taken care - * of the pages reserved for the memmap, so we can just jump to - * the end of that region and start processing the device pages. - */ - if (altmap) { - start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); - nr_pages = end_pfn - start_pfn; - } - - for (pfn = start_pfn; pfn < end_pfn; pfn += pfns_per_compound) { - struct page *page = pfn_to_page(pfn); - - __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); - - if (pfns_per_compound == 1) - continue; - - memmap_init_compound(page, pfn, zone_idx, nid, pgmap, - compound_nr_pages(altmap, pfns_per_compound)); - } - - pr_info("%s initialised %lu pages in %ums\n", __func__, - nr_pages, jiffies_to_msecs(jiffies - start)); -} - -#endif -static void __meminit zone_init_free_lists(struct zone *zone) -{ - unsigned int order, t; - for_each_migratetype_order(order, t) { - INIT_LIST_HEAD(&zone->free_area[order].free_list[t]); - zone->free_area[order].nr_free = 0; - } -} - -/* - * Only struct pages that correspond to ranges defined by memblock.memory - * are zeroed and initialized by going through __init_single_page() during - * memmap_init_zone_range(). - * - * But, there could be struct pages that correspond to holes in - * memblock.memory. This can happen because of the following reasons: - * - physical memory bank size is not necessarily the exact multiple of the - * arbitrary section size - * - early reserved memory may not be listed in memblock.memory - * - memory layouts defined with memmap= kernel parameter may not align - * nicely with memmap sections - * - * Explicitly initialize those struct pages so that: - * - PG_Reserved is set - * - zone and node links point to zone and node that span the page if the - * hole is in the middle of a zone - * - zone and node links point to adjacent zone/node if the hole falls on - * the zone boundary; the pages in such holes will be prepended to the - * zone/node above the hole except for the trailing pages in the last - * section that will be appended to the zone/node below. - */ -static void __init init_unavailable_range(unsigned long spfn, - unsigned long epfn, - int zone, int node) -{ - unsigned long pfn; - u64 pgcnt = 0; - - for (pfn = spfn; pfn < epfn; pfn++) { - if (!pfn_valid(pageblock_start_pfn(pfn))) { - pfn = pageblock_end_pfn(pfn) - 1; - continue; - } - __init_single_page(pfn_to_page(pfn), pfn, zone, node); - __SetPageReserved(pfn_to_page(pfn)); - pgcnt++; - } - - if (pgcnt) - pr_info("On node %d, zone %s: %lld pages in unavailable ranges", - node, zone_names[zone], pgcnt); -} - -static void __init memmap_init_zone_range(struct zone *zone, - unsigned long start_pfn, - unsigned long end_pfn, - unsigned long *hole_pfn) -{ - unsigned long zone_start_pfn = zone->zone_start_pfn; - unsigned long zone_end_pfn = zone_start_pfn + zone->spanned_pages; - int nid = zone_to_nid(zone), zone_id = zone_idx(zone); - - start_pfn = clamp(start_pfn, zone_start_pfn, zone_end_pfn); - end_pfn = clamp(end_pfn, zone_start_pfn, zone_end_pfn); - - if (start_pfn >= end_pfn) - return; - - memmap_init_range(end_pfn - start_pfn, nid, zone_id, start_pfn, - zone_end_pfn, MEMINIT_EARLY, NULL, MIGRATE_MOVABLE); - - if (*hole_pfn < start_pfn) - init_unavailable_range(*hole_pfn, start_pfn, zone_id, nid); - - *hole_pfn = end_pfn; -} - -static void __init memmap_init(void) -{ - unsigned long start_pfn, end_pfn; - unsigned long hole_pfn = 0; - int i, j, zone_id = 0, nid; - - for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { - struct pglist_data *node = NODE_DATA(nid); - - for (j = 0; j < MAX_NR_ZONES; j++) { - struct zone *zone = node->node_zones + j; - - if (!populated_zone(zone)) - continue; - - memmap_init_zone_range(zone, start_pfn, end_pfn, - &hole_pfn); - zone_id = j; - } - } - -#ifdef CONFIG_SPARSEMEM - /* - * Initialize the memory map for hole in the range [memory_end, - * section_end]. - * Append the pages in this hole to the highest zone in the last - * node. - * The call to init_unavailable_range() is outside the ifdef to - * silence the compiler warining about zone_id set but not used; - * for FLATMEM it is a nop anyway - */ - end_pfn = round_up(end_pfn, PAGES_PER_SECTION); - if (hole_pfn < end_pfn) -#endif - init_unavailable_range(hole_pfn, end_pfn, zone_id, nid); -} - -void __init *memmap_alloc(phys_addr_t size, phys_addr_t align, - phys_addr_t min_addr, int nid, bool exact_nid) -{ - void *ptr; - - if (exact_nid) - ptr = memblock_alloc_exact_nid_raw(size, align, min_addr, - MEMBLOCK_ALLOC_ACCESSIBLE, - nid); - else - ptr = memblock_alloc_try_nid_raw(size, align, min_addr, - MEMBLOCK_ALLOC_ACCESSIBLE, - nid); - - if (ptr && size > 0) - page_init_poison(ptr, size); - - return ptr; -} - -static int zone_batchsize(struct zone *zone) -{ -#ifdef CONFIG_MMU - int batch; - - /* - * The number of pages to batch allocate is either ~0.1% - * of the zone or 1MB, whichever is smaller. The batch - * size is striking a balance between allocation latency - * and zone lock contention. - */ - batch = min(zone_managed_pages(zone) >> 10, SZ_1M / PAGE_SIZE); - batch /= 4; /* We effectively *= 4 below */ - if (batch < 1) - batch = 1; - - /* - * Clamp the batch to a 2^n - 1 value. Having a power - * of 2 value was found to be more likely to have - * suboptimal cache aliasing properties in some cases. - * - * For example if 2 tasks are alternately allocating - * batches of pages, one task can end up with a lot - * of pages of one half of the possible page colors - * and the other with pages of the other colors. - */ - batch = rounddown_pow_of_two(batch + batch/2) - 1; - - return batch; + return batch; #else /* The deferral and batching of frees should be suppressed under NOMMU @@ -7071,1352 +6050,210 @@ static int zone_batchsize(struct zone *zone) static int zone_highsize(struct zone *zone, int batch, int cpu_online) { -#ifdef CONFIG_MMU - int high; - int nr_split_cpus; - unsigned long total_pages; - - if (!percpu_pagelist_high_fraction) { - /* - * By default, the high value of the pcp is based on the zone - * low watermark so that if they are full then background - * reclaim will not be started prematurely. - */ - total_pages = low_wmark_pages(zone); - } else { - /* - * If percpu_pagelist_high_fraction is configured, the high - * value is based on a fraction of the managed pages in the - * zone. - */ - total_pages = zone_managed_pages(zone) / percpu_pagelist_high_fraction; - } - - /* - * Split the high value across all online CPUs local to the zone. Note - * that early in boot that CPUs may not be online yet and that during - * CPU hotplug that the cpumask is not yet updated when a CPU is being - * onlined. For memory nodes that have no CPUs, split pcp->high across - * all online CPUs to mitigate the risk that reclaim is triggered - * prematurely due to pages stored on pcp lists. - */ - nr_split_cpus = cpumask_weight(cpumask_of_node(zone_to_nid(zone))) + cpu_online; - if (!nr_split_cpus) - nr_split_cpus = num_online_cpus(); - high = total_pages / nr_split_cpus; - - /* - * Ensure high is at least batch*4. The multiple is based on the - * historical relationship between high and batch. - */ - high = max(high, batch << 2); - - return high; -#else - return 0; -#endif -} - -/* - * pcp->high and pcp->batch values are related and generally batch is lower - * than high. They are also related to pcp->count such that count is lower - * than high, and as soon as it reaches high, the pcplist is flushed. - * - * However, guaranteeing these relations at all times would require e.g. write - * barriers here but also careful usage of read barriers at the read side, and - * thus be prone to error and bad for performance. Thus the update only prevents - * store tearing. Any new users of pcp->batch and pcp->high should ensure they - * can cope with those fields changing asynchronously, and fully trust only the - * pcp->count field on the local CPU with interrupts disabled. - * - * mutex_is_locked(&pcp_batch_high_lock) required when calling this function - * outside of boot time (or some other assurance that no concurrent updaters - * exist). - */ -static void pageset_update(struct per_cpu_pages *pcp, unsigned long high, - unsigned long batch) -{ - WRITE_ONCE(pcp->batch, batch); - WRITE_ONCE(pcp->high, high); -} - -static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonestat *pzstats) -{ - int pindex; - - memset(pcp, 0, sizeof(*pcp)); - memset(pzstats, 0, sizeof(*pzstats)); - - spin_lock_init(&pcp->lock); - for (pindex = 0; pindex < NR_PCP_LISTS; pindex++) - INIT_LIST_HEAD(&pcp->lists[pindex]); - - /* - * Set batch and high values safe for a boot pageset. A true percpu - * pageset's initialization will update them subsequently. Here we don't - * need to be as careful as pageset_update() as nobody can access the - * pageset yet. - */ - pcp->high = BOOT_PAGESET_HIGH; - pcp->batch = BOOT_PAGESET_BATCH; - pcp->free_factor = 0; -} - -static void __zone_set_pageset_high_and_batch(struct zone *zone, unsigned long high, - unsigned long batch) -{ - struct per_cpu_pages *pcp; - int cpu; - - for_each_possible_cpu(cpu) { - pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); - pageset_update(pcp, high, batch); - } -} - -/* - * Calculate and set new high and batch values for all per-cpu pagesets of a - * zone based on the zone's size. - */ -static void zone_set_pageset_high_and_batch(struct zone *zone, int cpu_online) -{ - int new_high, new_batch; - - new_batch = max(1, zone_batchsize(zone)); - new_high = zone_highsize(zone, new_batch, cpu_online); - - if (zone->pageset_high == new_high && - zone->pageset_batch == new_batch) - return; - - zone->pageset_high = new_high; - zone->pageset_batch = new_batch; - - __zone_set_pageset_high_and_batch(zone, new_high, new_batch); -} - -void __meminit setup_zone_pageset(struct zone *zone) -{ - int cpu; - - /* Size may be 0 on !SMP && !NUMA */ - if (sizeof(struct per_cpu_zonestat) > 0) - zone->per_cpu_zonestats = alloc_percpu(struct per_cpu_zonestat); - - zone->per_cpu_pageset = alloc_percpu(struct per_cpu_pages); - for_each_possible_cpu(cpu) { - struct per_cpu_pages *pcp; - struct per_cpu_zonestat *pzstats; - - pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); - pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu); - per_cpu_pages_init(pcp, pzstats); - } - - zone_set_pageset_high_and_batch(zone, 0); -} - -/* - * The zone indicated has a new number of managed_pages; batch sizes and percpu - * page high values need to be recalculated. - */ -static void zone_pcp_update(struct zone *zone, int cpu_online) -{ - mutex_lock(&pcp_batch_high_lock); - zone_set_pageset_high_and_batch(zone, cpu_online); - mutex_unlock(&pcp_batch_high_lock); -} - -/* - * Allocate per cpu pagesets and initialize them. - * Before this call only boot pagesets were available. - */ -void __init setup_per_cpu_pageset(void) -{ - struct pglist_data *pgdat; - struct zone *zone; - int __maybe_unused cpu; - - for_each_populated_zone(zone) - setup_zone_pageset(zone); - -#ifdef CONFIG_NUMA - /* - * Unpopulated zones continue using the boot pagesets. - * The numa stats for these pagesets need to be reset. - * Otherwise, they will end up skewing the stats of - * the nodes these zones are associated with. - */ - for_each_possible_cpu(cpu) { - struct per_cpu_zonestat *pzstats = &per_cpu(boot_zonestats, cpu); - memset(pzstats->vm_numa_event, 0, - sizeof(pzstats->vm_numa_event)); - } -#endif - - for_each_online_pgdat(pgdat) - pgdat->per_cpu_nodestats = - alloc_percpu(struct per_cpu_nodestat); -} - -static __meminit void zone_pcp_init(struct zone *zone) -{ - /* - * per cpu subsystem is not up at this point. The following code - * relies on the ability of the linker to provide the - * offset of a (static) per cpu variable into the per cpu area. - */ - zone->per_cpu_pageset = &boot_pageset; - zone->per_cpu_zonestats = &boot_zonestats; - zone->pageset_high = BOOT_PAGESET_HIGH; - zone->pageset_batch = BOOT_PAGESET_BATCH; - - if (populated_zone(zone)) - pr_debug(" %s zone: %lu pages, LIFO batch:%u\n", zone->name, - zone->present_pages, zone_batchsize(zone)); -} - -void __meminit init_currently_empty_zone(struct zone *zone, - unsigned long zone_start_pfn, - unsigned long size) -{ - struct pglist_data *pgdat = zone->zone_pgdat; - int zone_idx = zone_idx(zone) + 1; - - if (zone_idx > pgdat->nr_zones) - pgdat->nr_zones = zone_idx; - - zone->zone_start_pfn = zone_start_pfn; - - mminit_dprintk(MMINIT_TRACE, "memmap_init", - "Initialising map node %d zone %lu pfns %lu -> %lu\n", - pgdat->node_id, - (unsigned long)zone_idx(zone), - zone_start_pfn, (zone_start_pfn + size)); - - zone_init_free_lists(zone); - zone->initialized = 1; -} - -/** - * get_pfn_range_for_nid - Return the start and end page frames for a node - * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned. - * @start_pfn: Passed by reference. On return, it will have the node start_pfn. - * @end_pfn: Passed by reference. On return, it will have the node end_pfn. - * - * It returns the start and end page frame of a node based on information - * provided by memblock_set_node(). If called for a node - * with no available memory, a warning is printed and the start and end - * PFNs will be 0. - */ -void __init get_pfn_range_for_nid(unsigned int nid, - unsigned long *start_pfn, unsigned long *end_pfn) -{ - unsigned long this_start_pfn, this_end_pfn; - int i; - - *start_pfn = -1UL; - *end_pfn = 0; - - for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) { - *start_pfn = min(*start_pfn, this_start_pfn); - *end_pfn = max(*end_pfn, this_end_pfn); - } - - if (*start_pfn == -1UL) - *start_pfn = 0; -} - -/* - * This finds a zone that can be used for ZONE_MOVABLE pages. The - * assumption is made that zones within a node are ordered in monotonic - * increasing memory addresses so that the "highest" populated zone is used - */ -static void __init find_usable_zone_for_movable(void) -{ - int zone_index; - for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) { - if (zone_index == ZONE_MOVABLE) - continue; - - if (arch_zone_highest_possible_pfn[zone_index] > - arch_zone_lowest_possible_pfn[zone_index]) - break; - } - - VM_BUG_ON(zone_index == -1); - movable_zone = zone_index; -} - -/* - * The zone ranges provided by the architecture do not include ZONE_MOVABLE - * because it is sized independent of architecture. Unlike the other zones, - * the starting point for ZONE_MOVABLE is not fixed. It may be different - * in each node depending on the size of each node and how evenly kernelcore - * is distributed. This helper function adjusts the zone ranges - * provided by the architecture for a given node by using the end of the - * highest usable zone for ZONE_MOVABLE. This preserves the assumption that - * zones within a node are in order of monotonic increases memory addresses - */ -static void __init adjust_zone_range_for_zone_movable(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *zone_start_pfn, - unsigned long *zone_end_pfn) -{ - /* Only adjust if ZONE_MOVABLE is on this node */ - if (zone_movable_pfn[nid]) { - /* Size ZONE_MOVABLE */ - if (zone_type == ZONE_MOVABLE) { - *zone_start_pfn = zone_movable_pfn[nid]; - *zone_end_pfn = min(node_end_pfn, - arch_zone_highest_possible_pfn[movable_zone]); - - /* Adjust for ZONE_MOVABLE starting within this range */ - } else if (!mirrored_kernelcore && - *zone_start_pfn < zone_movable_pfn[nid] && - *zone_end_pfn > zone_movable_pfn[nid]) { - *zone_end_pfn = zone_movable_pfn[nid]; - - /* Check if this whole range is within ZONE_MOVABLE */ - } else if (*zone_start_pfn >= zone_movable_pfn[nid]) - *zone_start_pfn = *zone_end_pfn; - } -} - -/* - * Return the number of pages a zone spans in a node, including holes - * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node() - */ -static unsigned long __init zone_spanned_pages_in_node(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *zone_start_pfn, - unsigned long *zone_end_pfn) -{ - unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; - unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; - /* When hotadd a new node from cpu_up(), the node should be empty */ - if (!node_start_pfn && !node_end_pfn) - return 0; - - /* Get the start and end of the zone */ - *zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); - *zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); - adjust_zone_range_for_zone_movable(nid, zone_type, - node_start_pfn, node_end_pfn, - zone_start_pfn, zone_end_pfn); - - /* Check that this node has pages within the zone's required range */ - if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn) - return 0; - - /* Move the zone boundaries inside the node if necessary */ - *zone_end_pfn = min(*zone_end_pfn, node_end_pfn); - *zone_start_pfn = max(*zone_start_pfn, node_start_pfn); - - /* Return the spanned pages */ - return *zone_end_pfn - *zone_start_pfn; -} - -/* - * Return the number of holes in a range on a node. If nid is MAX_NUMNODES, - * then all holes in the requested range will be accounted for. - */ -unsigned long __init __absent_pages_in_range(int nid, - unsigned long range_start_pfn, - unsigned long range_end_pfn) -{ - unsigned long nr_absent = range_end_pfn - range_start_pfn; - unsigned long start_pfn, end_pfn; - int i; - - for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { - start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn); - end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn); - nr_absent -= end_pfn - start_pfn; - } - return nr_absent; -} - -/** - * absent_pages_in_range - Return number of page frames in holes within a range - * @start_pfn: The start PFN to start searching for holes - * @end_pfn: The end PFN to stop searching for holes - * - * Return: the number of pages frames in memory holes within a range. - */ -unsigned long __init absent_pages_in_range(unsigned long start_pfn, - unsigned long end_pfn) -{ - return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn); -} - -/* Return the number of page frames in holes in a zone on a node */ -static unsigned long __init zone_absent_pages_in_node(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn) -{ - unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; - unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; - unsigned long zone_start_pfn, zone_end_pfn; - unsigned long nr_absent; - - /* When hotadd a new node from cpu_up(), the node should be empty */ - if (!node_start_pfn && !node_end_pfn) - return 0; - - zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); - zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); - - adjust_zone_range_for_zone_movable(nid, zone_type, - node_start_pfn, node_end_pfn, - &zone_start_pfn, &zone_end_pfn); - nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); - - /* - * ZONE_MOVABLE handling. - * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages - * and vice versa. - */ - if (mirrored_kernelcore && zone_movable_pfn[nid]) { - unsigned long start_pfn, end_pfn; - struct memblock_region *r; - - for_each_mem_region(r) { - start_pfn = clamp(memblock_region_memory_base_pfn(r), - zone_start_pfn, zone_end_pfn); - end_pfn = clamp(memblock_region_memory_end_pfn(r), - zone_start_pfn, zone_end_pfn); - - if (zone_type == ZONE_MOVABLE && - memblock_is_mirror(r)) - nr_absent += end_pfn - start_pfn; - - if (zone_type == ZONE_NORMAL && - !memblock_is_mirror(r)) - nr_absent += end_pfn - start_pfn; - } - } - - return nr_absent; -} - -static void __init calculate_node_totalpages(struct pglist_data *pgdat, - unsigned long node_start_pfn, - unsigned long node_end_pfn) -{ - unsigned long realtotalpages = 0, totalpages = 0; - enum zone_type i; - - for (i = 0; i < MAX_NR_ZONES; i++) { - struct zone *zone = pgdat->node_zones + i; - unsigned long zone_start_pfn, zone_end_pfn; - unsigned long spanned, absent; - unsigned long size, real_size; - - spanned = zone_spanned_pages_in_node(pgdat->node_id, i, - node_start_pfn, - node_end_pfn, - &zone_start_pfn, - &zone_end_pfn); - absent = zone_absent_pages_in_node(pgdat->node_id, i, - node_start_pfn, - node_end_pfn); - - size = spanned; - real_size = size - absent; - - if (size) - zone->zone_start_pfn = zone_start_pfn; - else - zone->zone_start_pfn = 0; - zone->spanned_pages = size; - zone->present_pages = real_size; -#if defined(CONFIG_MEMORY_HOTPLUG) - zone->present_early_pages = real_size; -#endif - - totalpages += size; - realtotalpages += real_size; - } - - pgdat->node_spanned_pages = totalpages; - pgdat->node_present_pages = realtotalpages; - pr_debug("On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages); -} - -#ifndef CONFIG_SPARSEMEM -/* - * Calculate the size of the zone->blockflags rounded to an unsigned long - * Start by making sure zonesize is a multiple of pageblock_order by rounding - * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally - * round what is now in bits to nearest long in bits, then return it in - * bytes. - */ -static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize) -{ - unsigned long usemapsize; - - zonesize += zone_start_pfn & (pageblock_nr_pages-1); - usemapsize = roundup(zonesize, pageblock_nr_pages); - usemapsize = usemapsize >> pageblock_order; - usemapsize *= NR_PAGEBLOCK_BITS; - usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long)); - - return usemapsize / 8; -} - -static void __ref setup_usemap(struct zone *zone) -{ - unsigned long usemapsize = usemap_size(zone->zone_start_pfn, - zone->spanned_pages); - zone->pageblock_flags = NULL; - if (usemapsize) { - zone->pageblock_flags = - memblock_alloc_node(usemapsize, SMP_CACHE_BYTES, - zone_to_nid(zone)); - if (!zone->pageblock_flags) - panic("Failed to allocate %ld bytes for zone %s pageblock flags on node %d\n", - usemapsize, zone->name, zone_to_nid(zone)); - } -} -#else -static inline void setup_usemap(struct zone *zone) {} -#endif /* CONFIG_SPARSEMEM */ - -#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE - -/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ -void __init set_pageblock_order(void) -{ - unsigned int order = MAX_ORDER; - - /* Check that pageblock_nr_pages has not already been setup */ - if (pageblock_order) - return; - - /* Don't let pageblocks exceed the maximum allocation granularity. */ - if (HPAGE_SHIFT > PAGE_SHIFT && HUGETLB_PAGE_ORDER < order) - order = HUGETLB_PAGE_ORDER; - - /* - * Assume the largest contiguous order of interest is a huge page. - * This value may be variable depending on boot parameters on IA64 and - * powerpc. - */ - pageblock_order = order; -} -#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ - -/* - * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() - * is unused as pageblock_order is set at compile-time. See - * include/linux/pageblock-flags.h for the values of pageblock_order based on - * the kernel config - */ -void __init set_pageblock_order(void) -{ -} - -#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ - -static unsigned long __init calc_memmap_size(unsigned long spanned_pages, - unsigned long present_pages) -{ - unsigned long pages = spanned_pages; - - /* - * Provide a more accurate estimation if there are holes within - * the zone and SPARSEMEM is in use. If there are holes within the - * zone, each populated memory region may cost us one or two extra - * memmap pages due to alignment because memmap pages for each - * populated regions may not be naturally aligned on page boundary. - * So the (present_pages >> 4) heuristic is a tradeoff for that. - */ - if (spanned_pages > present_pages + (present_pages >> 4) && - IS_ENABLED(CONFIG_SPARSEMEM)) - pages = present_pages; - - return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT; -} - -#ifdef CONFIG_TRANSPARENT_HUGEPAGE -static void pgdat_init_split_queue(struct pglist_data *pgdat) -{ - struct deferred_split *ds_queue = &pgdat->deferred_split_queue; - - spin_lock_init(&ds_queue->split_queue_lock); - INIT_LIST_HEAD(&ds_queue->split_queue); - ds_queue->split_queue_len = 0; -} -#else -static void pgdat_init_split_queue(struct pglist_data *pgdat) {} -#endif - -#ifdef CONFIG_COMPACTION -static void pgdat_init_kcompactd(struct pglist_data *pgdat) -{ - init_waitqueue_head(&pgdat->kcompactd_wait); -} -#else -static void pgdat_init_kcompactd(struct pglist_data *pgdat) {} -#endif - -static void __meminit pgdat_init_internals(struct pglist_data *pgdat) -{ - int i; - - pgdat_resize_init(pgdat); - pgdat_kswapd_lock_init(pgdat); - - pgdat_init_split_queue(pgdat); - pgdat_init_kcompactd(pgdat); - - init_waitqueue_head(&pgdat->kswapd_wait); - init_waitqueue_head(&pgdat->pfmemalloc_wait); - - for (i = 0; i < NR_VMSCAN_THROTTLE; i++) - init_waitqueue_head(&pgdat->reclaim_wait[i]); - - pgdat_page_ext_init(pgdat); - lruvec_init(&pgdat->__lruvec); -} - -static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx, int nid, - unsigned long remaining_pages) -{ - atomic_long_set(&zone->managed_pages, remaining_pages); - zone_set_nid(zone, nid); - zone->name = zone_names[idx]; - zone->zone_pgdat = NODE_DATA(nid); - spin_lock_init(&zone->lock); - zone_seqlock_init(zone); - zone_pcp_init(zone); -} - -/* - * Set up the zone data structures - * - init pgdat internals - * - init all zones belonging to this node - * - * NOTE: this function is only called during memory hotplug - */ -#ifdef CONFIG_MEMORY_HOTPLUG -void __ref free_area_init_core_hotplug(struct pglist_data *pgdat) -{ - int nid = pgdat->node_id; - enum zone_type z; - int cpu; - - pgdat_init_internals(pgdat); - - if (pgdat->per_cpu_nodestats == &boot_nodestats) - pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); - - /* - * Reset the nr_zones, order and highest_zoneidx before reuse. - * Note that kswapd will init kswapd_highest_zoneidx properly - * when it starts in the near future. - */ - pgdat->nr_zones = 0; - pgdat->kswapd_order = 0; - pgdat->kswapd_highest_zoneidx = 0; - pgdat->node_start_pfn = 0; - for_each_online_cpu(cpu) { - struct per_cpu_nodestat *p; - - p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu); - memset(p, 0, sizeof(*p)); - } - - for (z = 0; z < MAX_NR_ZONES; z++) - zone_init_internals(&pgdat->node_zones[z], z, nid, 0); -} -#endif - -/* - * Set up the zone data structures: - * - mark all pages reserved - * - mark all memory queues empty - * - clear the memory bitmaps - * - * NOTE: pgdat should get zeroed by caller. - * NOTE: this function is only called during early init. - */ -static void __init free_area_init_core(struct pglist_data *pgdat) -{ - enum zone_type j; - int nid = pgdat->node_id; - - pgdat_init_internals(pgdat); - pgdat->per_cpu_nodestats = &boot_nodestats; - - for (j = 0; j < MAX_NR_ZONES; j++) { - struct zone *zone = pgdat->node_zones + j; - unsigned long size, freesize, memmap_pages; - - size = zone->spanned_pages; - freesize = zone->present_pages; - - /* - * Adjust freesize so that it accounts for how much memory - * is used by this zone for memmap. This affects the watermark - * and per-cpu initialisations - */ - memmap_pages = calc_memmap_size(size, freesize); - if (!is_highmem_idx(j)) { - if (freesize >= memmap_pages) { - freesize -= memmap_pages; - if (memmap_pages) - pr_debug(" %s zone: %lu pages used for memmap\n", - zone_names[j], memmap_pages); - } else - pr_warn(" %s zone: %lu memmap pages exceeds freesize %lu\n", - zone_names[j], memmap_pages, freesize); - } - - /* Account for reserved pages */ - if (j == 0 && freesize > dma_reserve) { - freesize -= dma_reserve; - pr_debug(" %s zone: %lu pages reserved\n", zone_names[0], dma_reserve); - } - - if (!is_highmem_idx(j)) - nr_kernel_pages += freesize; - /* Charge for highmem memmap if there are enough kernel pages */ - else if (nr_kernel_pages > memmap_pages * 2) - nr_kernel_pages -= memmap_pages; - nr_all_pages += freesize; - - /* - * Set an approximate value for lowmem here, it will be adjusted - * when the bootmem allocator frees pages into the buddy system. - * And all highmem pages will be managed by the buddy system. - */ - zone_init_internals(zone, j, nid, freesize); - - if (!size) - continue; - - set_pageblock_order(); - setup_usemap(zone); - init_currently_empty_zone(zone, zone->zone_start_pfn, size); - } -} - -#ifdef CONFIG_FLATMEM -static void __init alloc_node_mem_map(struct pglist_data *pgdat) -{ - unsigned long __maybe_unused start = 0; - unsigned long __maybe_unused offset = 0; - - /* Skip empty nodes */ - if (!pgdat->node_spanned_pages) - return; - - start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1); - offset = pgdat->node_start_pfn - start; - /* ia64 gets its own node_mem_map, before this, without bootmem */ - if (!pgdat->node_mem_map) { - unsigned long size, end; - struct page *map; - - /* - * The zone's endpoints aren't required to be MAX_ORDER - * aligned but the node_mem_map endpoints must be in order - * for the buddy allocator to function correctly. - */ - end = pgdat_end_pfn(pgdat); - end = ALIGN(end, MAX_ORDER_NR_PAGES); - size = (end - start) * sizeof(struct page); - map = memmap_alloc(size, SMP_CACHE_BYTES, MEMBLOCK_LOW_LIMIT, - pgdat->node_id, false); - if (!map) - panic("Failed to allocate %ld bytes for node %d memory map\n", - size, pgdat->node_id); - pgdat->node_mem_map = map + offset; - } - pr_debug("%s: node %d, pgdat %08lx, node_mem_map %08lx\n", - __func__, pgdat->node_id, (unsigned long)pgdat, - (unsigned long)pgdat->node_mem_map); -#ifndef CONFIG_NUMA - /* - * With no DISCONTIG, the global mem_map is just set as node 0's - */ - if (pgdat == NODE_DATA(0)) { - mem_map = NODE_DATA(0)->node_mem_map; - if (page_to_pfn(mem_map) != pgdat->node_start_pfn) - mem_map -= offset; - } -#endif -} -#else -static inline void alloc_node_mem_map(struct pglist_data *pgdat) { } -#endif /* CONFIG_FLATMEM */ - -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT -static inline void pgdat_set_deferred_range(pg_data_t *pgdat) -{ - pgdat->first_deferred_pfn = ULONG_MAX; -} -#else -static inline void pgdat_set_deferred_range(pg_data_t *pgdat) {} -#endif - -static void __init free_area_init_node(int nid) -{ - pg_data_t *pgdat = NODE_DATA(nid); - unsigned long start_pfn = 0; - unsigned long end_pfn = 0; - - /* pg_data_t should be reset to zero when it's allocated */ - WARN_ON(pgdat->nr_zones || pgdat->kswapd_highest_zoneidx); - - get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); - - pgdat->node_id = nid; - pgdat->node_start_pfn = start_pfn; - pgdat->per_cpu_nodestats = NULL; - - if (start_pfn != end_pfn) { - pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid, - (u64)start_pfn << PAGE_SHIFT, - end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0); - } else { - pr_info("Initmem setup node %d as memoryless\n", nid); - } - - calculate_node_totalpages(pgdat, start_pfn, end_pfn); - - alloc_node_mem_map(pgdat); - pgdat_set_deferred_range(pgdat); - - free_area_init_core(pgdat); - lru_gen_init_pgdat(pgdat); -} - -static void __init free_area_init_memoryless_node(int nid) -{ - free_area_init_node(nid); -} - -#if MAX_NUMNODES > 1 -/* - * Figure out the number of possible node ids. - */ -void __init setup_nr_node_ids(void) -{ - unsigned int highest; - - highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES); - nr_node_ids = highest + 1; -} -#endif - -/** - * node_map_pfn_alignment - determine the maximum internode alignment - * - * This function should be called after node map is populated and sorted. - * It calculates the maximum power of two alignment which can distinguish - * all the nodes. - * - * For example, if all nodes are 1GiB and aligned to 1GiB, the return value - * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the - * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is - * shifted, 1GiB is enough and this function will indicate so. - * - * This is used to test whether pfn -> nid mapping of the chosen memory - * model has fine enough granularity to avoid incorrect mapping for the - * populated node map. - * - * Return: the determined alignment in pfn's. 0 if there is no alignment - * requirement (single node). - */ -unsigned long __init node_map_pfn_alignment(void) -{ - unsigned long accl_mask = 0, last_end = 0; - unsigned long start, end, mask; - int last_nid = NUMA_NO_NODE; - int i, nid; - - for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) { - if (!start || last_nid < 0 || last_nid == nid) { - last_nid = nid; - last_end = end; - continue; - } - - /* - * Start with a mask granular enough to pin-point to the - * start pfn and tick off bits one-by-one until it becomes - * too coarse to separate the current node from the last. - */ - mask = ~((1 << __ffs(start)) - 1); - while (mask && last_end <= (start & (mask << 1))) - mask <<= 1; - - /* accumulate all internode masks */ - accl_mask |= mask; - } - - /* convert mask to number of pages */ - return ~accl_mask + 1; -} - -/* - * early_calculate_totalpages() - * Sum pages in active regions for movable zone. - * Populate N_MEMORY for calculating usable_nodes. - */ -static unsigned long __init early_calculate_totalpages(void) -{ - unsigned long totalpages = 0; - unsigned long start_pfn, end_pfn; - int i, nid; - - for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { - unsigned long pages = end_pfn - start_pfn; - - totalpages += pages; - if (pages) - node_set_state(nid, N_MEMORY); - } - return totalpages; -} - -/* - * Find the PFN the Movable zone begins in each node. Kernel memory - * is spread evenly between nodes as long as the nodes have enough - * memory. When they don't, some nodes will have more kernelcore than - * others - */ -static void __init find_zone_movable_pfns_for_nodes(void) -{ - int i, nid; - unsigned long usable_startpfn; - unsigned long kernelcore_node, kernelcore_remaining; - /* save the state before borrow the nodemask */ - nodemask_t saved_node_state = node_states[N_MEMORY]; - unsigned long totalpages = early_calculate_totalpages(); - int usable_nodes = nodes_weight(node_states[N_MEMORY]); - struct memblock_region *r; - - /* Need to find movable_zone earlier when movable_node is specified. */ - find_usable_zone_for_movable(); - - /* - * If movable_node is specified, ignore kernelcore and movablecore - * options. - */ - if (movable_node_is_enabled()) { - for_each_mem_region(r) { - if (!memblock_is_hotpluggable(r)) - continue; - - nid = memblock_get_region_node(r); - - usable_startpfn = PFN_DOWN(r->base); - zone_movable_pfn[nid] = zone_movable_pfn[nid] ? - min(usable_startpfn, zone_movable_pfn[nid]) : - usable_startpfn; - } - - goto out2; - } - - /* - * If kernelcore=mirror is specified, ignore movablecore option - */ - if (mirrored_kernelcore) { - bool mem_below_4gb_not_mirrored = false; - - for_each_mem_region(r) { - if (memblock_is_mirror(r)) - continue; - - nid = memblock_get_region_node(r); - - usable_startpfn = memblock_region_memory_base_pfn(r); - - if (usable_startpfn < PHYS_PFN(SZ_4G)) { - mem_below_4gb_not_mirrored = true; - continue; - } - - zone_movable_pfn[nid] = zone_movable_pfn[nid] ? - min(usable_startpfn, zone_movable_pfn[nid]) : - usable_startpfn; - } - - if (mem_below_4gb_not_mirrored) - pr_warn("This configuration results in unmirrored kernel memory.\n"); - - goto out2; - } - - /* - * If kernelcore=nn% or movablecore=nn% was specified, calculate the - * amount of necessary memory. - */ - if (required_kernelcore_percent) - required_kernelcore = (totalpages * 100 * required_kernelcore_percent) / - 10000UL; - if (required_movablecore_percent) - required_movablecore = (totalpages * 100 * required_movablecore_percent) / - 10000UL; - - /* - * If movablecore= was specified, calculate what size of - * kernelcore that corresponds so that memory usable for - * any allocation type is evenly spread. If both kernelcore - * and movablecore are specified, then the value of kernelcore - * will be used for required_kernelcore if it's greater than - * what movablecore would have allowed. - */ - if (required_movablecore) { - unsigned long corepages; - - /* - * Round-up so that ZONE_MOVABLE is at least as large as what - * was requested by the user - */ - required_movablecore = - roundup(required_movablecore, MAX_ORDER_NR_PAGES); - required_movablecore = min(totalpages, required_movablecore); - corepages = totalpages - required_movablecore; - - required_kernelcore = max(required_kernelcore, corepages); - } - - /* - * If kernelcore was not specified or kernelcore size is larger - * than totalpages, there is no ZONE_MOVABLE. - */ - if (!required_kernelcore || required_kernelcore >= totalpages) - goto out; - - /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */ - usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone]; - -restart: - /* Spread kernelcore memory as evenly as possible throughout nodes */ - kernelcore_node = required_kernelcore / usable_nodes; - for_each_node_state(nid, N_MEMORY) { - unsigned long start_pfn, end_pfn; +#ifdef CONFIG_MMU + int high; + int nr_split_cpus; + unsigned long total_pages; + if (!percpu_pagelist_high_fraction) { /* - * Recalculate kernelcore_node if the division per node - * now exceeds what is necessary to satisfy the requested - * amount of memory for the kernel + * By default, the high value of the pcp is based on the zone + * low watermark so that if they are full then background + * reclaim will not be started prematurely. */ - if (required_kernelcore < kernelcore_node) - kernelcore_node = required_kernelcore / usable_nodes; - + total_pages = low_wmark_pages(zone); + } else { /* - * As the map is walked, we track how much memory is usable - * by the kernel using kernelcore_remaining. When it is - * 0, the rest of the node is usable by ZONE_MOVABLE + * If percpu_pagelist_high_fraction is configured, the high + * value is based on a fraction of the managed pages in the + * zone. */ - kernelcore_remaining = kernelcore_node; - - /* Go through each range of PFNs within this node */ - for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { - unsigned long size_pages; - - start_pfn = max(start_pfn, zone_movable_pfn[nid]); - if (start_pfn >= end_pfn) - continue; - - /* Account for what is only usable for kernelcore */ - if (start_pfn < usable_startpfn) { - unsigned long kernel_pages; - kernel_pages = min(end_pfn, usable_startpfn) - - start_pfn; - - kernelcore_remaining -= min(kernel_pages, - kernelcore_remaining); - required_kernelcore -= min(kernel_pages, - required_kernelcore); - - /* Continue if range is now fully accounted */ - if (end_pfn <= usable_startpfn) { - - /* - * Push zone_movable_pfn to the end so - * that if we have to rebalance - * kernelcore across nodes, we will - * not double account here - */ - zone_movable_pfn[nid] = end_pfn; - continue; - } - start_pfn = usable_startpfn; - } - - /* - * The usable PFN range for ZONE_MOVABLE is from - * start_pfn->end_pfn. Calculate size_pages as the - * number of pages used as kernelcore - */ - size_pages = end_pfn - start_pfn; - if (size_pages > kernelcore_remaining) - size_pages = kernelcore_remaining; - zone_movable_pfn[nid] = start_pfn + size_pages; - - /* - * Some kernelcore has been met, update counts and - * break if the kernelcore for this node has been - * satisfied - */ - required_kernelcore -= min(required_kernelcore, - size_pages); - kernelcore_remaining -= size_pages; - if (!kernelcore_remaining) - break; - } + total_pages = zone_managed_pages(zone) / percpu_pagelist_high_fraction; } /* - * If there is still required_kernelcore, we do another pass with one - * less node in the count. This will push zone_movable_pfn[nid] further - * along on the nodes that still have memory until kernelcore is - * satisfied + * Split the high value across all online CPUs local to the zone. Note + * that early in boot that CPUs may not be online yet and that during + * CPU hotplug that the cpumask is not yet updated when a CPU is being + * onlined. For memory nodes that have no CPUs, split pcp->high across + * all online CPUs to mitigate the risk that reclaim is triggered + * prematurely due to pages stored on pcp lists. */ - usable_nodes--; - if (usable_nodes && required_kernelcore > usable_nodes) - goto restart; - -out2: - /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */ - for (nid = 0; nid < MAX_NUMNODES; nid++) { - unsigned long start_pfn, end_pfn; - - zone_movable_pfn[nid] = - roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES); - - get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); - if (zone_movable_pfn[nid] >= end_pfn) - zone_movable_pfn[nid] = 0; - } - -out: - /* restore the node_state */ - node_states[N_MEMORY] = saved_node_state; -} + nr_split_cpus = cpumask_weight(cpumask_of_node(zone_to_nid(zone))) + cpu_online; + if (!nr_split_cpus) + nr_split_cpus = num_online_cpus(); + high = total_pages / nr_split_cpus; -/* Any regular or high memory on that node ? */ -static void check_for_memory(pg_data_t *pgdat, int nid) -{ - enum zone_type zone_type; + /* + * Ensure high is at least batch*4. The multiple is based on the + * historical relationship between high and batch. + */ + high = max(high, batch << 2); - for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) { - struct zone *zone = &pgdat->node_zones[zone_type]; - if (populated_zone(zone)) { - if (IS_ENABLED(CONFIG_HIGHMEM)) - node_set_state(nid, N_HIGH_MEMORY); - if (zone_type <= ZONE_NORMAL) - node_set_state(nid, N_NORMAL_MEMORY); - break; - } - } + return high; +#else + return 0; +#endif } /* - * Some architectures, e.g. ARC may have ZONE_HIGHMEM below ZONE_NORMAL. For - * such cases we allow max_zone_pfn sorted in the descending order + * pcp->high and pcp->batch values are related and generally batch is lower + * than high. They are also related to pcp->count such that count is lower + * than high, and as soon as it reaches high, the pcplist is flushed. + * + * However, guaranteeing these relations at all times would require e.g. write + * barriers here but also careful usage of read barriers at the read side, and + * thus be prone to error and bad for performance. Thus the update only prevents + * store tearing. Any new users of pcp->batch and pcp->high should ensure they + * can cope with those fields changing asynchronously, and fully trust only the + * pcp->count field on the local CPU with interrupts disabled. + * + * mutex_is_locked(&pcp_batch_high_lock) required when calling this function + * outside of boot time (or some other assurance that no concurrent updaters + * exist). */ -bool __weak arch_has_descending_max_zone_pfns(void) +static void pageset_update(struct per_cpu_pages *pcp, unsigned long high, + unsigned long batch) { - return false; + WRITE_ONCE(pcp->batch, batch); + WRITE_ONCE(pcp->high, high); } -/** - * free_area_init - Initialise all pg_data_t and zone data - * @max_zone_pfn: an array of max PFNs for each zone - * - * This will call free_area_init_node() for each active node in the system. - * Using the page ranges provided by memblock_set_node(), the size of each - * zone in each node and their holes is calculated. If the maximum PFN - * between two adjacent zones match, it is assumed that the zone is empty. - * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed - * that arch_max_dma32_pfn has no pages. It is also assumed that a zone - * starts where the previous one ended. For example, ZONE_DMA32 starts - * at arch_max_dma_pfn. - */ -void __init free_area_init(unsigned long *max_zone_pfn) +static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonestat *pzstats) { - unsigned long start_pfn, end_pfn; - int i, nid, zone; - bool descending; - - /* Record where the zone boundaries are */ - memset(arch_zone_lowest_possible_pfn, 0, - sizeof(arch_zone_lowest_possible_pfn)); - memset(arch_zone_highest_possible_pfn, 0, - sizeof(arch_zone_highest_possible_pfn)); - - start_pfn = PHYS_PFN(memblock_start_of_DRAM()); - descending = arch_has_descending_max_zone_pfns(); - - for (i = 0; i < MAX_NR_ZONES; i++) { - if (descending) - zone = MAX_NR_ZONES - i - 1; - else - zone = i; - - if (zone == ZONE_MOVABLE) - continue; + int pindex; - end_pfn = max(max_zone_pfn[zone], start_pfn); - arch_zone_lowest_possible_pfn[zone] = start_pfn; - arch_zone_highest_possible_pfn[zone] = end_pfn; + memset(pcp, 0, sizeof(*pcp)); + memset(pzstats, 0, sizeof(*pzstats)); - start_pfn = end_pfn; - } + spin_lock_init(&pcp->lock); + for (pindex = 0; pindex < NR_PCP_LISTS; pindex++) + INIT_LIST_HEAD(&pcp->lists[pindex]); - /* Find the PFNs that ZONE_MOVABLE begins at in each node */ - memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn)); - find_zone_movable_pfns_for_nodes(); + /* + * Set batch and high values safe for a boot pageset. A true percpu + * pageset's initialization will update them subsequently. Here we don't + * need to be as careful as pageset_update() as nobody can access the + * pageset yet. + */ + pcp->high = BOOT_PAGESET_HIGH; + pcp->batch = BOOT_PAGESET_BATCH; + pcp->free_factor = 0; +} - /* Print out the zone ranges */ - pr_info("Zone ranges:\n"); - for (i = 0; i < MAX_NR_ZONES; i++) { - if (i == ZONE_MOVABLE) - continue; - pr_info(" %-8s ", zone_names[i]); - if (arch_zone_lowest_possible_pfn[i] == - arch_zone_highest_possible_pfn[i]) - pr_cont("empty\n"); - else - pr_cont("[mem %#018Lx-%#018Lx]\n", - (u64)arch_zone_lowest_possible_pfn[i] - << PAGE_SHIFT, - ((u64)arch_zone_highest_possible_pfn[i] - << PAGE_SHIFT) - 1); - } +static void __zone_set_pageset_high_and_batch(struct zone *zone, unsigned long high, + unsigned long batch) +{ + struct per_cpu_pages *pcp; + int cpu; - /* Print out the PFNs ZONE_MOVABLE begins at in each node */ - pr_info("Movable zone start for each node\n"); - for (i = 0; i < MAX_NUMNODES; i++) { - if (zone_movable_pfn[i]) - pr_info(" Node %d: %#018Lx\n", i, - (u64)zone_movable_pfn[i] << PAGE_SHIFT); + for_each_possible_cpu(cpu) { + pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); + pageset_update(pcp, high, batch); } +} - /* - * Print out the early node map, and initialize the - * subsection-map relative to active online memory ranges to - * enable future "sub-section" extensions of the memory map. - */ - pr_info("Early memory node ranges\n"); - for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { - pr_info(" node %3d: [mem %#018Lx-%#018Lx]\n", nid, - (u64)start_pfn << PAGE_SHIFT, - ((u64)end_pfn << PAGE_SHIFT) - 1); - subsection_map_init(start_pfn, end_pfn - start_pfn); - } - - /* Initialise every node */ - mminit_verify_pageflags_layout(); - setup_nr_node_ids(); - for_each_node(nid) { - pg_data_t *pgdat; - - if (!node_online(nid)) { - pr_info("Initializing node %d as memoryless\n", nid); - - /* Allocator not initialized yet */ - pgdat = arch_alloc_nodedata(nid); - if (!pgdat) - panic("Cannot allocate %zuB for node %d.\n", - sizeof(*pgdat), nid); - arch_refresh_nodedata(nid, pgdat); - free_area_init_memoryless_node(nid); +/* + * Calculate and set new high and batch values for all per-cpu pagesets of a + * zone based on the zone's size. + */ +static void zone_set_pageset_high_and_batch(struct zone *zone, int cpu_online) +{ + int new_high, new_batch; - /* - * We do not want to confuse userspace by sysfs - * files/directories for node without any memory - * attached to it, so this node is not marked as - * N_MEMORY and not marked online so that no sysfs - * hierarchy will be created via register_one_node for - * it. The pgdat will get fully initialized by - * hotadd_init_pgdat() when memory is hotplugged into - * this node. - */ - continue; - } + new_batch = max(1, zone_batchsize(zone)); + new_high = zone_highsize(zone, new_batch, cpu_online); - pgdat = NODE_DATA(nid); - free_area_init_node(nid); + if (zone->pageset_high == new_high && + zone->pageset_batch == new_batch) + return; - /* Any memory on that node */ - if (pgdat->node_present_pages) - node_set_state(nid, N_MEMORY); - check_for_memory(pgdat, nid); - } + zone->pageset_high = new_high; + zone->pageset_batch = new_batch; - memmap_init(); + __zone_set_pageset_high_and_batch(zone, new_high, new_batch); } -static int __init cmdline_parse_core(char *p, unsigned long *core, - unsigned long *percent) +void __meminit setup_zone_pageset(struct zone *zone) { - unsigned long long coremem; - char *endptr; - - if (!p) - return -EINVAL; + int cpu; - /* Value may be a percentage of total memory, otherwise bytes */ - coremem = simple_strtoull(p, &endptr, 0); - if (*endptr == '%') { - /* Paranoid check for percent values greater than 100 */ - WARN_ON(coremem > 100); + /* Size may be 0 on !SMP && !NUMA */ + if (sizeof(struct per_cpu_zonestat) > 0) + zone->per_cpu_zonestats = alloc_percpu(struct per_cpu_zonestat); - *percent = coremem; - } else { - coremem = memparse(p, &p); - /* Paranoid check that UL is enough for the coremem value */ - WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX); + zone->per_cpu_pageset = alloc_percpu(struct per_cpu_pages); + for_each_possible_cpu(cpu) { + struct per_cpu_pages *pcp; + struct per_cpu_zonestat *pzstats; - *core = coremem >> PAGE_SHIFT; - *percent = 0UL; + pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); + pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu); + per_cpu_pages_init(pcp, pzstats); } - return 0; + + zone_set_pageset_high_and_batch(zone, 0); } /* - * kernelcore=size sets the amount of memory for use for allocations that - * cannot be reclaimed or migrated. + * The zone indicated has a new number of managed_pages; batch sizes and percpu + * page high values need to be recalculated. */ -static int __init cmdline_parse_kernelcore(char *p) +static void zone_pcp_update(struct zone *zone, int cpu_online) { - /* parse kernelcore=mirror */ - if (parse_option_str(p, "mirror")) { - mirrored_kernelcore = true; - return 0; - } - - return cmdline_parse_core(p, &required_kernelcore, - &required_kernelcore_percent); + mutex_lock(&pcp_batch_high_lock); + zone_set_pageset_high_and_batch(zone, cpu_online); + mutex_unlock(&pcp_batch_high_lock); } /* - * movablecore=size sets the amount of memory for use for allocations that - * can be reclaimed or migrated. + * Allocate per cpu pagesets and initialize them. + * Before this call only boot pagesets were available. */ -static int __init cmdline_parse_movablecore(char *p) +void __init setup_per_cpu_pageset(void) { - return cmdline_parse_core(p, &required_movablecore, - &required_movablecore_percent); + struct pglist_data *pgdat; + struct zone *zone; + int __maybe_unused cpu; + + for_each_populated_zone(zone) + setup_zone_pageset(zone); + +#ifdef CONFIG_NUMA + /* + * Unpopulated zones continue using the boot pagesets. + * The numa stats for these pagesets need to be reset. + * Otherwise, they will end up skewing the stats of + * the nodes these zones are associated with. + */ + for_each_possible_cpu(cpu) { + struct per_cpu_zonestat *pzstats = &per_cpu(boot_zonestats, cpu); + memset(pzstats->vm_numa_event, 0, + sizeof(pzstats->vm_numa_event)); + } +#endif + + for_each_online_pgdat(pgdat) + pgdat->per_cpu_nodestats = + alloc_percpu(struct per_cpu_nodestat); } -early_param("kernelcore", cmdline_parse_kernelcore); -early_param("movablecore", cmdline_parse_movablecore); +__meminit void zone_pcp_init(struct zone *zone) +{ + /* + * per cpu subsystem is not up at this point. The following code + * relies on the ability of the linker to provide the + * offset of a (static) per cpu variable into the per cpu area. + */ + zone->per_cpu_pageset = &boot_pageset; + zone->per_cpu_zonestats = &boot_zonestats; + zone->pageset_high = BOOT_PAGESET_HIGH; + zone->pageset_batch = BOOT_PAGESET_BATCH; + + if (populated_zone(zone)) + pr_debug(" %s zone: %lu pages, LIFO batch:%u\n", zone->name, + zone->present_pages, zone_batchsize(zone)); +} void adjust_managed_page_count(struct page *page, long count) { @@ -8516,22 +6353,6 @@ void __init mem_init_print_info(void) ); } -/** - * set_dma_reserve - set the specified number of pages reserved in the first zone - * @new_dma_reserve: The number of pages to mark reserved - * - * The per-cpu batchsize and zone watermarks are determined by managed_pages. - * In the DMA zone, a significant percentage may be consumed by kernel image - * and other unfreeable allocations which can skew the watermarks badly. This - * function may optionally be used to account for unfreeable pages in the - * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and - * smaller per-cpu batchsize. - */ -void __init set_dma_reserve(unsigned long new_dma_reserve) -{ - dma_reserve = new_dma_reserve; -} - static int page_alloc_cpu_dead(unsigned int cpu) { struct zone *zone; @@ -8976,149 +6797,6 @@ out: return ret; } -#ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES -/* - * Returns the number of pages that arch has reserved but - * is not known to alloc_large_system_hash(). - */ -static unsigned long __init arch_reserved_kernel_pages(void) -{ - return 0; -} -#endif - -/* - * Adaptive scale is meant to reduce sizes of hash tables on large memory - * machines. As memory size is increased the scale is also increased but at - * slower pace. Starting from ADAPT_SCALE_BASE (64G), every time memory - * quadruples the scale is increased by one, which means the size of hash table - * only doubles, instead of quadrupling as well. - * Because 32-bit systems cannot have large physical memory, where this scaling - * makes sense, it is disabled on such platforms. - */ -#if __BITS_PER_LONG > 32 -#define ADAPT_SCALE_BASE (64ul << 30) -#define ADAPT_SCALE_SHIFT 2 -#define ADAPT_SCALE_NPAGES (ADAPT_SCALE_BASE >> PAGE_SHIFT) -#endif - -/* - * allocate a large system hash table from bootmem - * - it is assumed that the hash table must contain an exact power-of-2 - * quantity of entries - * - limit is the number of hash buckets, not the total allocation size - */ -void *__init alloc_large_system_hash(const char *tablename, - unsigned long bucketsize, - unsigned long numentries, - int scale, - int flags, - unsigned int *_hash_shift, - unsigned int *_hash_mask, - unsigned long low_limit, - unsigned long high_limit) -{ - unsigned long long max = high_limit; - unsigned long log2qty, size; - void *table; - gfp_t gfp_flags; - bool virt; - bool huge; - - /* allow the kernel cmdline to have a say */ - if (!numentries) { - /* round applicable memory size up to nearest megabyte */ - numentries = nr_kernel_pages; - numentries -= arch_reserved_kernel_pages(); - - /* It isn't necessary when PAGE_SIZE >= 1MB */ - if (PAGE_SIZE < SZ_1M) - numentries = round_up(numentries, SZ_1M / PAGE_SIZE); - -#if __BITS_PER_LONG > 32 - if (!high_limit) { - unsigned long adapt; - - for (adapt = ADAPT_SCALE_NPAGES; adapt < numentries; - adapt <<= ADAPT_SCALE_SHIFT) - scale++; - } -#endif - - /* limit to 1 bucket per 2^scale bytes of low memory */ - if (scale > PAGE_SHIFT) - numentries >>= (scale - PAGE_SHIFT); - else - numentries <<= (PAGE_SHIFT - scale); - - /* Make sure we've got at least a 0-order allocation.. */ - if (unlikely(flags & HASH_SMALL)) { - /* Makes no sense without HASH_EARLY */ - WARN_ON(!(flags & HASH_EARLY)); - if (!(numentries >> *_hash_shift)) { - numentries = 1UL << *_hash_shift; - BUG_ON(!numentries); - } - } else if (unlikely((numentries * bucketsize) < PAGE_SIZE)) - numentries = PAGE_SIZE / bucketsize; - } - numentries = roundup_pow_of_two(numentries); - - /* limit allocation size to 1/16 total memory by default */ - if (max == 0) { - max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; - do_div(max, bucketsize); - } - max = min(max, 0x80000000ULL); - - if (numentries < low_limit) - numentries = low_limit; - if (numentries > max) - numentries = max; - - log2qty = ilog2(numentries); - - gfp_flags = (flags & HASH_ZERO) ? GFP_ATOMIC | __GFP_ZERO : GFP_ATOMIC; - do { - virt = false; - size = bucketsize << log2qty; - if (flags & HASH_EARLY) { - if (flags & HASH_ZERO) - table = memblock_alloc(size, SMP_CACHE_BYTES); - else - table = memblock_alloc_raw(size, - SMP_CACHE_BYTES); - } else if (get_order(size) > MAX_ORDER || hashdist) { - table = vmalloc_huge(size, gfp_flags); - virt = true; - if (table) - huge = is_vm_area_hugepages(table); - } else { - /* - * If bucketsize is not a power-of-two, we may free - * some pages at the end of hash table which - * alloc_pages_exact() automatically does - */ - table = alloc_pages_exact(size, gfp_flags); - kmemleak_alloc(table, size, 1, gfp_flags); - } - } while (!table && size > PAGE_SIZE && --log2qty); - - if (!table) - panic("Failed to allocate %s hash table\n", tablename); - - pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n", - tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size, - virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear"); - - if (_hash_shift) - *_hash_shift = log2qty; - if (_hash_mask) - *_hash_mask = (1 << log2qty) - 1; - - return table; -} - #ifdef CONFIG_CONTIG_ALLOC #if defined(CONFIG_DYNAMIC_DEBUG) || \ (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) -- cgit v1.2.3 From c4fbed4b0284d91797ee3cf60983b94c84c396b6 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:04 +0200 Subject: mm/page_alloc: rename page_alloc_init() to page_alloc_init_cpuhp() The page_alloc_init() name is really misleading because all this function does is sets up CPU hotplug callbacks for the page allocator. Rename it to page_alloc_init_cpuhp() so that name will reflect what the function does. Link: https://lkml.kernel.org/r/20230321170513.2401534-6-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Reviewed-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/gfp.h | 2 +- init/main.c | 2 +- mm/page_alloc.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 7c554e4bd49f..ed8cb537c6a7 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -319,7 +319,7 @@ extern void page_frag_free(void *addr); #define __free_page(page) __free_pages((page), 0) #define free_page(addr) free_pages((addr), 0) -void page_alloc_init(void); +void page_alloc_init_cpuhp(void); void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp); void drain_all_pages(struct zone *zone); void drain_local_pages(struct zone *zone); diff --git a/init/main.c b/init/main.c index bb87b789c543..f285bc53c345 100644 --- a/init/main.c +++ b/init/main.c @@ -973,7 +973,7 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void) boot_cpu_hotplug_init(); build_all_zonelists(NULL); - page_alloc_init(); + page_alloc_init_cpuhp(); pr_notice("Kernel command line: %s\n", saved_command_line); /* parameters may set static keys */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 3abc994bcfa1..1131b87586d5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6393,7 +6393,7 @@ static int page_alloc_cpu_online(unsigned int cpu) return 0; } -void __init page_alloc_init(void) +void __init page_alloc_init_cpuhp(void) { int ret; -- cgit v1.2.3 From b7ec1bf3e7b9dd9d3335c937f5d834680d74addf Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:06 +0200 Subject: init,mm: move mm_init() to mm/mm_init.c and rename it to mm_core_init() Make mm_init() a part of mm/ codebase. mm_core_init() better describes what the function does and does not clash with mm_init() in kernel/fork.c Link: https://lkml.kernel.org/r/20230321170513.2401534-8-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Acked-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/mm.h | 1 + init/main.c | 71 ++-------------------------------------------------- mm/mm_init.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 76 insertions(+), 69 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 1f79667824eb..6be179cec081 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -38,6 +38,7 @@ struct pt_regs; extern int sysctl_page_lock_unfairness; +void mm_core_init(void); void init_mm_internals(void); #ifndef CONFIG_NUMA /* Don't use mapnrs, do it properly */ diff --git a/init/main.c b/init/main.c index c240cce5bc86..f1b2d8d80987 100644 --- a/init/main.c +++ b/init/main.c @@ -807,73 +807,6 @@ static inline void initcall_debug_enable(void) } #endif -/* Report memory auto-initialization states for this boot. */ -static void __init report_meminit(void) -{ - const char *stack; - - if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN)) - stack = "all(pattern)"; - else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO)) - stack = "all(zero)"; - else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) - stack = "byref_all(zero)"; - else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) - stack = "byref(zero)"; - else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) - stack = "__user(zero)"; - else - stack = "off"; - - pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", - stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", - want_init_on_free() ? "on" : "off"); - if (want_init_on_free()) - pr_info("mem auto-init: clearing system memory may take some time...\n"); -} - -/* - * Set up kernel memory allocators - */ -static void __init mm_init(void) -{ - /* Initializations relying on SMP setup */ - build_all_zonelists(NULL); - page_alloc_init_cpuhp(); - - /* - * page_ext requires contiguous pages, - * bigger than MAX_ORDER unless SPARSEMEM. - */ - page_ext_init_flatmem(); - init_mem_debugging_and_hardening(); - kfence_alloc_pool(); - report_meminit(); - kmsan_init_shadow(); - stack_depot_early_init(); - mem_init(); - mem_init_print_info(); - kmem_cache_init(); - /* - * page_owner must be initialized after buddy is ready, and also after - * slab is ready so that stack_depot_init() works properly - */ - page_ext_init_flatmem_late(); - kmemleak_init(); - pgtable_init(); - debug_objects_mem_init(); - vmalloc_init(); - /* If no deferred init page_ext now, as vmap is fully initialized */ - if (!deferred_struct_pages) - page_ext_init(); - /* Should be run before the first non-init thread is created */ - init_espfix_bsp(); - /* Should be run after espfix64 is set up. */ - pti_init(); - kmsan_init_runtime(); - mm_cache_init(); -} - #ifdef CONFIG_RANDOMIZE_KSTACK_OFFSET DEFINE_STATIC_KEY_MAYBE_RO(CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT, randomize_kstack_offset); @@ -997,13 +930,13 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void) /* * These use large bootmem allocations and must precede - * kmem_cache_init() + * initalization of page allocator */ setup_log_buf(0); vfs_caches_init_early(); sort_main_extable(); trap_init(); - mm_init(); + mm_core_init(); poking_init(); ftrace_init(); diff --git a/mm/mm_init.c b/mm/mm_init.c index 2e60c7186132..bba73f1fb277 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -20,9 +20,15 @@ #include #include #include +#include +#include +#include +#include #include "internal.h" #include "shuffle.h" +#include + #ifdef CONFIG_DEBUG_MEMORY_INIT int __meminitdata mminit_loglevel; @@ -2524,3 +2530,70 @@ void __init memblock_free_pages(struct page *page, unsigned long pfn, } __free_pages_core(page, order); } + +/* Report memory auto-initialization states for this boot. */ +static void __init report_meminit(void) +{ + const char *stack; + + if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN)) + stack = "all(pattern)"; + else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO)) + stack = "all(zero)"; + else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)) + stack = "byref_all(zero)"; + else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)) + stack = "byref(zero)"; + else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER)) + stack = "__user(zero)"; + else + stack = "off"; + + pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n", + stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off", + want_init_on_free() ? "on" : "off"); + if (want_init_on_free()) + pr_info("mem auto-init: clearing system memory may take some time...\n"); +} + +/* + * Set up kernel memory allocators + */ +void __init mm_core_init(void) +{ + /* Initializations relying on SMP setup */ + build_all_zonelists(NULL); + page_alloc_init_cpuhp(); + + /* + * page_ext requires contiguous pages, + * bigger than MAX_ORDER unless SPARSEMEM. + */ + page_ext_init_flatmem(); + init_mem_debugging_and_hardening(); + kfence_alloc_pool(); + report_meminit(); + kmsan_init_shadow(); + stack_depot_early_init(); + mem_init(); + mem_init_print_info(); + kmem_cache_init(); + /* + * page_owner must be initialized after buddy is ready, and also after + * slab is ready so that stack_depot_init() works properly + */ + page_ext_init_flatmem_late(); + kmemleak_init(); + pgtable_init(); + debug_objects_mem_init(); + vmalloc_init(); + /* If no deferred init page_ext now, as vmap is fully initialized */ + if (!deferred_struct_pages) + page_ext_init(); + /* Should be run before the first non-init thread is created */ + init_espfix_bsp(); + /* Should be run after espfix64 is set up. */ + pti_init(); + kmsan_init_runtime(); + mm_cache_init(); +} -- cgit v1.2.3 From 4cd1e9edf60efb20fad35cf5e9ade7ad75b34cd1 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:07 +0200 Subject: mm: call {ptlock,pgtable}_cache_init() directly from mm_core_init() and drop pgtable_init() as it has no real value and its name is misleading. Link: https://lkml.kernel.org/r/20230321170513.2401534-9-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Reviewed-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Cc: Sergei Shtylyov Signed-off-by: Andrew Morton --- include/linux/mm.h | 6 ------ mm/mm_init.c | 3 ++- 2 files changed, 2 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 6be179cec081..dfff8bcaa766 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2637,12 +2637,6 @@ static inline bool ptlock_init(struct page *page) { return true; } static inline void ptlock_free(struct page *page) {} #endif /* USE_SPLIT_PTE_PTLOCKS */ -static inline void pgtable_init(void) -{ - ptlock_cache_init(); - pgtable_cache_init(); -} - static inline bool pgtable_pte_page_ctor(struct page *page) { if (!ptlock_init(page)) diff --git a/mm/mm_init.c b/mm/mm_init.c index bba73f1fb277..f1475413394d 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -2584,7 +2584,8 @@ void __init mm_core_init(void) */ page_ext_init_flatmem_late(); kmemleak_init(); - pgtable_init(); + ptlock_cache_init(); + pgtable_cache_init(); debug_objects_mem_init(); vmalloc_init(); /* If no deferred init page_ext now, as vmap is fully initialized */ -- cgit v1.2.3 From f2fc4b44ec2bb94c51c7ae1af9b1177d72705992 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:08 +0200 Subject: mm: move init_mem_debugging_and_hardening() to mm/mm_init.c init_mem_debugging_and_hardening() is only called from mm_core_init(). Move it close to the caller, make it static and rename it to mem_debugging_and_hardening_init() for consistency with surrounding convention. Link: https://lkml.kernel.org/r/20230321170513.2401534-10-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Acked-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/mm.h | 1 - mm/internal.h | 8 +++++ mm/mm_init.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++- mm/page_alloc.c | 95 ------------------------------------------------------ 4 files changed, 98 insertions(+), 97 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index dfff8bcaa766..0fa6a6f94eda 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3251,7 +3251,6 @@ extern int apply_to_existing_page_range(struct mm_struct *mm, unsigned long address, unsigned long size, pte_fn_t fn, void *data); -extern void __init init_mem_debugging_and_hardening(void); #ifdef CONFIG_PAGE_POISONING extern void __kernel_poison_pages(struct page *page, int numpages); extern void __kernel_unpoison_pages(struct page *page, int numpages); diff --git a/mm/internal.h b/mm/internal.h index 22f1410a0ee3..a2934c610182 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -204,6 +204,14 @@ pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); extern char * const zone_names[MAX_NR_ZONES]; +/* perform sanity checks on struct pages being allocated or freed */ +DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); + +static inline bool is_check_pages_enabled(void) +{ + return static_branch_unlikely(&check_pages_enabled); +} + /* * Structure for holding the mostly immutable allocation parameters passed * between functions involved in allocations, including the alloc_pages* diff --git a/mm/mm_init.c b/mm/mm_init.c index f1475413394d..43f6d3ed24ef 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -2531,6 +2531,95 @@ void __init memblock_free_pages(struct page *page, unsigned long pfn, __free_pages_core(page, order); } +static bool _init_on_alloc_enabled_early __read_mostly + = IS_ENABLED(CONFIG_INIT_ON_ALLOC_DEFAULT_ON); +static int __init early_init_on_alloc(char *buf) +{ + + return kstrtobool(buf, &_init_on_alloc_enabled_early); +} +early_param("init_on_alloc", early_init_on_alloc); + +static bool _init_on_free_enabled_early __read_mostly + = IS_ENABLED(CONFIG_INIT_ON_FREE_DEFAULT_ON); +static int __init early_init_on_free(char *buf) +{ + return kstrtobool(buf, &_init_on_free_enabled_early); +} +early_param("init_on_free", early_init_on_free); + +DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); + +/* + * Enable static keys related to various memory debugging and hardening options. + * Some override others, and depend on early params that are evaluated in the + * order of appearance. So we need to first gather the full picture of what was + * enabled, and then make decisions. + */ +static void __init mem_debugging_and_hardening_init(void) +{ + bool page_poisoning_requested = false; + bool want_check_pages = false; + +#ifdef CONFIG_PAGE_POISONING + /* + * Page poisoning is debug page alloc for some arches. If + * either of those options are enabled, enable poisoning. + */ + if (page_poisoning_enabled() || + (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) && + debug_pagealloc_enabled())) { + static_branch_enable(&_page_poisoning_enabled); + page_poisoning_requested = true; + want_check_pages = true; + } +#endif + + if ((_init_on_alloc_enabled_early || _init_on_free_enabled_early) && + page_poisoning_requested) { + pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, " + "will take precedence over init_on_alloc and init_on_free\n"); + _init_on_alloc_enabled_early = false; + _init_on_free_enabled_early = false; + } + + if (_init_on_alloc_enabled_early) { + want_check_pages = true; + static_branch_enable(&init_on_alloc); + } else { + static_branch_disable(&init_on_alloc); + } + + if (_init_on_free_enabled_early) { + want_check_pages = true; + static_branch_enable(&init_on_free); + } else { + static_branch_disable(&init_on_free); + } + + if (IS_ENABLED(CONFIG_KMSAN) && + (_init_on_alloc_enabled_early || _init_on_free_enabled_early)) + pr_info("mem auto-init: please make sure init_on_alloc and init_on_free are disabled when running KMSAN\n"); + +#ifdef CONFIG_DEBUG_PAGEALLOC + if (debug_pagealloc_enabled()) { + want_check_pages = true; + static_branch_enable(&_debug_pagealloc_enabled); + + if (debug_guardpage_minorder()) + static_branch_enable(&_debug_guardpage_enabled); + } +#endif + + /* + * Any page debugging or hardening option also enables sanity checking + * of struct pages being allocated or freed. With CONFIG_DEBUG_VM it's + * enabled already. + */ + if (!IS_ENABLED(CONFIG_DEBUG_VM) && want_check_pages) + static_branch_enable(&check_pages_enabled); +} + /* Report memory auto-initialization states for this boot. */ static void __init report_meminit(void) { @@ -2570,7 +2659,7 @@ void __init mm_core_init(void) * bigger than MAX_ORDER unless SPARSEMEM. */ page_ext_init_flatmem(); - init_mem_debugging_and_hardening(); + mem_debugging_and_hardening_init(); kfence_alloc_pool(); report_meminit(); kmsan_init_shadow(); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1131b87586d5..94bf3b7b5c49 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -240,31 +240,6 @@ EXPORT_SYMBOL(init_on_alloc); DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free); EXPORT_SYMBOL(init_on_free); -/* perform sanity checks on struct pages being allocated or freed */ -static DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); - -static inline bool is_check_pages_enabled(void) -{ - return static_branch_unlikely(&check_pages_enabled); -} - -static bool _init_on_alloc_enabled_early __read_mostly - = IS_ENABLED(CONFIG_INIT_ON_ALLOC_DEFAULT_ON); -static int __init early_init_on_alloc(char *buf) -{ - - return kstrtobool(buf, &_init_on_alloc_enabled_early); -} -early_param("init_on_alloc", early_init_on_alloc); - -static bool _init_on_free_enabled_early __read_mostly - = IS_ENABLED(CONFIG_INIT_ON_FREE_DEFAULT_ON); -static int __init early_init_on_free(char *buf) -{ - return kstrtobool(buf, &_init_on_free_enabled_early); -} -early_param("init_on_free", early_init_on_free); - /* * A cached value of the page's pageblock's migratetype, used when the page is * put on a pcplist. Used to avoid the pageblock migratetype lookup when @@ -798,76 +773,6 @@ static inline void clear_page_guard(struct zone *zone, struct page *page, unsigned int order, int migratetype) {} #endif -/* - * Enable static keys related to various memory debugging and hardening options. - * Some override others, and depend on early params that are evaluated in the - * order of appearance. So we need to first gather the full picture of what was - * enabled, and then make decisions. - */ -void __init init_mem_debugging_and_hardening(void) -{ - bool page_poisoning_requested = false; - bool want_check_pages = false; - -#ifdef CONFIG_PAGE_POISONING - /* - * Page poisoning is debug page alloc for some arches. If - * either of those options are enabled, enable poisoning. - */ - if (page_poisoning_enabled() || - (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) && - debug_pagealloc_enabled())) { - static_branch_enable(&_page_poisoning_enabled); - page_poisoning_requested = true; - want_check_pages = true; - } -#endif - - if ((_init_on_alloc_enabled_early || _init_on_free_enabled_early) && - page_poisoning_requested) { - pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, " - "will take precedence over init_on_alloc and init_on_free\n"); - _init_on_alloc_enabled_early = false; - _init_on_free_enabled_early = false; - } - - if (_init_on_alloc_enabled_early) { - want_check_pages = true; - static_branch_enable(&init_on_alloc); - } else { - static_branch_disable(&init_on_alloc); - } - - if (_init_on_free_enabled_early) { - want_check_pages = true; - static_branch_enable(&init_on_free); - } else { - static_branch_disable(&init_on_free); - } - - if (IS_ENABLED(CONFIG_KMSAN) && - (_init_on_alloc_enabled_early || _init_on_free_enabled_early)) - pr_info("mem auto-init: please make sure init_on_alloc and init_on_free are disabled when running KMSAN\n"); - -#ifdef CONFIG_DEBUG_PAGEALLOC - if (debug_pagealloc_enabled()) { - want_check_pages = true; - static_branch_enable(&_debug_pagealloc_enabled); - - if (debug_guardpage_minorder()) - static_branch_enable(&_debug_guardpage_enabled); - } -#endif - - /* - * Any page debugging or hardening option also enables sanity checking - * of struct pages being allocated or freed. With CONFIG_DEBUG_VM it's - * enabled already. - */ - if (!IS_ENABLED(CONFIG_DEBUG_VM) && want_check_pages) - static_branch_enable(&check_pages_enabled); -} - static inline void set_buddy_order(struct page *page, unsigned int order) { set_page_private(page, order); -- cgit v1.2.3 From de57807e6f267a658a046dbca44dc40fe806d60f Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:09 +0200 Subject: init,mm: fold late call to page_ext_init() to page_alloc_init_late() When deferred initialization of struct pages is enabled, page_ext_init() must be called after all the deferred initialization is done, but there is no point to keep it a separate call from kernel_init_freeable() right after page_alloc_init_late(). Fold the call to page_ext_init() into page_alloc_init_late() and localize deferred_struct_pages variable. Link: https://lkml.kernel.org/r/20230321170513.2401534-11-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Reviewed-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/page_ext.h | 2 -- init/main.c | 4 ---- mm/mm_init.c | 6 +++++- 3 files changed, 5 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h index bc2e39090a1f..67314f648aeb 100644 --- a/include/linux/page_ext.h +++ b/include/linux/page_ext.h @@ -29,8 +29,6 @@ struct page_ext_operations { bool need_shared_flags; }; -extern bool deferred_struct_pages; - #ifdef CONFIG_PAGE_EXTENSION /* diff --git a/init/main.c b/init/main.c index f1b2d8d80987..43bc4c82dc58 100644 --- a/init/main.c +++ b/init/main.c @@ -62,7 +62,6 @@ #include #include #include -#include #include #include #include @@ -1565,9 +1564,6 @@ static noinline void __init kernel_init_freeable(void) padata_init(); page_alloc_init_late(); - /* Initialize page ext after all struct pages are initialized. */ - if (deferred_struct_pages) - page_ext_init(); do_basic_setup(); diff --git a/mm/mm_init.c b/mm/mm_init.c index 43f6d3ed24ef..ff70da11e797 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -225,7 +225,7 @@ static unsigned long nr_kernel_pages __initdata; static unsigned long nr_all_pages __initdata; static unsigned long dma_reserve __initdata; -bool deferred_struct_pages __meminitdata; +static bool deferred_struct_pages __meminitdata; static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); @@ -2358,6 +2358,10 @@ void __init page_alloc_init_late(void) for_each_populated_zone(zone) set_zone_contiguous(zone); + + /* Initialize page ext after all struct pages are initialized. */ + if (deferred_struct_pages) + page_ext_init(); } #ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES -- cgit v1.2.3 From eb8589b4f8c107c346421881963c0ee0b8367c2c Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:10 +0200 Subject: mm: move mem_init_print_info() to mm_init.c mem_init_print_info() is only called from mm_core_init(). Move it close to the caller and make it static. Link: https://lkml.kernel.org/r/20230321170513.2401534-12-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Acked-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/mm.h | 1 - mm/internal.h | 1 + mm/mm_init.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++ mm/page_alloc.c | 53 ----------------------------------------------------- 4 files changed, 54 insertions(+), 54 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 0fa6a6f94eda..c3abad7e6ccb 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2780,7 +2780,6 @@ extern unsigned long free_reserved_area(void *start, void *end, int poison, const char *s); extern void adjust_managed_page_count(struct page *page, long count); -extern void mem_init_print_info(void); extern void reserve_bootmem_region(phys_addr_t start, phys_addr_t end); diff --git a/mm/internal.h b/mm/internal.h index a2934c610182..7cea7d833c50 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -201,6 +201,7 @@ pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); /* * in mm/page_alloc.c */ +#define K(x) ((x) << (PAGE_SHIFT-10)) extern char * const zone_names[MAX_NR_ZONES]; diff --git a/mm/mm_init.c b/mm/mm_init.c index ff70da11e797..8adadf51bbd2 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -24,6 +24,8 @@ #include #include #include +#include +#include #include "internal.h" #include "shuffle.h" @@ -2649,6 +2651,57 @@ static void __init report_meminit(void) pr_info("mem auto-init: clearing system memory may take some time...\n"); } +static void __init mem_init_print_info(void) +{ + unsigned long physpages, codesize, datasize, rosize, bss_size; + unsigned long init_code_size, init_data_size; + + physpages = get_num_physpages(); + codesize = _etext - _stext; + datasize = _edata - _sdata; + rosize = __end_rodata - __start_rodata; + bss_size = __bss_stop - __bss_start; + init_data_size = __init_end - __init_begin; + init_code_size = _einittext - _sinittext; + + /* + * Detect special cases and adjust section sizes accordingly: + * 1) .init.* may be embedded into .data sections + * 2) .init.text.* may be out of [__init_begin, __init_end], + * please refer to arch/tile/kernel/vmlinux.lds.S. + * 3) .rodata.* may be embedded into .text or .data sections. + */ +#define adj_init_size(start, end, size, pos, adj) \ + do { \ + if (&start[0] <= &pos[0] && &pos[0] < &end[0] && size > adj) \ + size -= adj; \ + } while (0) + + adj_init_size(__init_begin, __init_end, init_data_size, + _sinittext, init_code_size); + adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size); + adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size); + adj_init_size(_stext, _etext, codesize, __start_rodata, rosize); + adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize); + +#undef adj_init_size + + pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved" +#ifdef CONFIG_HIGHMEM + ", %luK highmem" +#endif + ")\n", + K(nr_free_pages()), K(physpages), + codesize / SZ_1K, datasize / SZ_1K, rosize / SZ_1K, + (init_data_size + init_code_size) / SZ_1K, bss_size / SZ_1K, + K(physpages - totalram_pages() - totalcma_pages), + K(totalcma_pages) +#ifdef CONFIG_HIGHMEM + , K(totalhigh_pages()) +#endif + ); +} + /* * Set up kernel memory allocators */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 94bf3b7b5c49..d0eb280ec7e4 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5246,8 +5246,6 @@ static bool show_mem_node_skip(unsigned int flags, int nid, nodemask_t *nodemask return !node_isset(nid, *nodemask); } -#define K(x) ((x) << (PAGE_SHIFT-10)) - static void show_migration_types(unsigned char type) { static const char types[MIGRATE_TYPES] = { @@ -6207,57 +6205,6 @@ unsigned long free_reserved_area(void *start, void *end, int poison, const char return pages; } -void __init mem_init_print_info(void) -{ - unsigned long physpages, codesize, datasize, rosize, bss_size; - unsigned long init_code_size, init_data_size; - - physpages = get_num_physpages(); - codesize = _etext - _stext; - datasize = _edata - _sdata; - rosize = __end_rodata - __start_rodata; - bss_size = __bss_stop - __bss_start; - init_data_size = __init_end - __init_begin; - init_code_size = _einittext - _sinittext; - - /* - * Detect special cases and adjust section sizes accordingly: - * 1) .init.* may be embedded into .data sections - * 2) .init.text.* may be out of [__init_begin, __init_end], - * please refer to arch/tile/kernel/vmlinux.lds.S. - * 3) .rodata.* may be embedded into .text or .data sections. - */ -#define adj_init_size(start, end, size, pos, adj) \ - do { \ - if (&start[0] <= &pos[0] && &pos[0] < &end[0] && size > adj) \ - size -= adj; \ - } while (0) - - adj_init_size(__init_begin, __init_end, init_data_size, - _sinittext, init_code_size); - adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size); - adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size); - adj_init_size(_stext, _etext, codesize, __start_rodata, rosize); - adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize); - -#undef adj_init_size - - pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved" -#ifdef CONFIG_HIGHMEM - ", %luK highmem" -#endif - ")\n", - K(nr_free_pages()), K(physpages), - codesize / SZ_1K, datasize / SZ_1K, rosize / SZ_1K, - (init_data_size + init_code_size) / SZ_1K, bss_size / SZ_1K, - K(physpages - totalram_pages() - totalcma_pages), - K(totalcma_pages) -#ifdef CONFIG_HIGHMEM - , K(totalhigh_pages()) -#endif - ); -} - static int page_alloc_cpu_dead(unsigned int cpu) { struct zone *zone; -- cgit v1.2.3 From d5d2c02a4980c2e22037679457bf2d921b86a503 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:11 +0200 Subject: mm: move kmem_cache_init() declaration to mm/slab.h kmem_cache_init() is called only from mm_core_init(), there is no need to declare it in include/linux/slab.h Move kmem_cache_init() declaration to mm/slab.h Link: https://lkml.kernel.org/r/20230321170513.2401534-13-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Reviewed-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/slab.h | 1 - mm/mm_init.c | 1 + mm/slab.h | 1 + 3 files changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/slab.h b/include/linux/slab.h index aa4575ef2965..f8b1d63c63a3 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -167,7 +167,6 @@ struct mem_cgroup; /* * struct kmem_cache related prototypes */ -void __init kmem_cache_init(void); bool slab_is_available(void); struct kmem_cache *kmem_cache_create(const char *name, unsigned int size, diff --git a/mm/mm_init.c b/mm/mm_init.c index 8adadf51bbd2..53fb8e9d1e3b 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -27,6 +27,7 @@ #include #include #include "internal.h" +#include "slab.h" #include "shuffle.h" #include diff --git a/mm/slab.h b/mm/slab.h index 43966aa5fadf..3f8df2244f5a 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -4,6 +4,7 @@ /* * Internal slab definitions */ +void __init kmem_cache_init(void); /* Reuses the bits in struct page */ struct slab { -- cgit v1.2.3 From b671491199acd3609f87754d268f2f5cb10de18d Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Tue, 21 Mar 2023 19:05:12 +0200 Subject: mm: move vmalloc_init() declaration to mm/internal.h vmalloc_init() is called only from mm_core_init(), there is no need to declare it in include/linux/vmalloc.h Move vmalloc_init() declaration to mm/internal.h Link: https://lkml.kernel.org/r/20230321170513.2401534-14-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Reviewed-by: David Hildenbrand Reviewed-by: Vlastimil Babka Cc: Doug Berger Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- include/linux/vmalloc.h | 4 ---- mm/internal.h | 5 +++++ 2 files changed, 5 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 69250efa03d1..351fc7697214 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -131,12 +131,8 @@ extern void *vm_map_ram(struct page **pages, unsigned int count, int node); extern void vm_unmap_aliases(void); #ifdef CONFIG_MMU -extern void __init vmalloc_init(void); extern unsigned long vmalloc_nr_pages(void); #else -static inline void vmalloc_init(void) -{ -} static inline unsigned long vmalloc_nr_pages(void) { return 0; } #endif diff --git a/mm/internal.h b/mm/internal.h index 7cea7d833c50..82ba61d0ed6a 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -879,9 +879,14 @@ size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, * mm/vmalloc.c */ #ifdef CONFIG_MMU +void __init vmalloc_init(void); int vmap_pages_range_noflush(unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, unsigned int page_shift); #else +static inline void vmalloc_init(void) +{ +} + static inline int vmap_pages_range_noflush(unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, unsigned int page_shift) -- cgit v1.2.3 From bd23024b9774e681cbe6cc3afcb24244dfcb2390 Mon Sep 17 00:00:00 2001 From: Tomas Mudrunka Date: Tue, 21 Mar 2023 11:34:30 +0100 Subject: mm/memtest: add results of early memtest to /proc/meminfo Currently the memtest results were only presented in dmesg. When running a large fleet of devices without ECC RAM it's currently not easy to do bulk monitoring for memory corruption. You have to parse dmesg, but that's a ring buffer so the error might disappear after some time. In general I do not consider dmesg to be a great API to query RAM status. In several companies I've seen such errors remain undetected and cause issues for way too long. So I think it makes sense to provide a monitoring API, so that we can safely detect and act upon them. This adds /proc/meminfo entry which can be easily used by scripts. Link: https://lkml.kernel.org/r/20230321103430.7130-1-tomas.mudrunka@gmail.com Signed-off-by: Tomas Mudrunka Cc: Jonathan Corbet Cc: Mike Rapoport (IBM) Signed-off-by: Andrew Morton --- Documentation/filesystems/proc.rst | 8 ++++++++ fs/proc/meminfo.c | 13 +++++++++++++ include/linux/memblock.h | 2 ++ mm/memtest.c | 6 ++++++ 4 files changed, 29 insertions(+) (limited to 'include') diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst index 9d5fd9424e8b..8740362f31c6 100644 --- a/Documentation/filesystems/proc.rst +++ b/Documentation/filesystems/proc.rst @@ -996,6 +996,7 @@ Example output. You may not have all of these fields. VmallocUsed: 40444 kB VmallocChunk: 0 kB Percpu: 29312 kB + EarlyMemtestBad: 0 kB HardwareCorrupted: 0 kB AnonHugePages: 4149248 kB ShmemHugePages: 0 kB @@ -1146,6 +1147,13 @@ VmallocChunk Percpu Memory allocated to the percpu allocator used to back percpu allocations. This stat excludes the cost of metadata. +EarlyMemtestBad + The amount of RAM/memory in kB, that was identified as corrupted + by early memtest. If memtest was not run, this field will not + be displayed at all. Size is never rounded down to 0 kB. + That means if 0 kB is reported, you can safely assume + there was at least one pass of memtest and none of the passes + found a single faulty byte of RAM. HardwareCorrupted The amount of RAM/memory in KB, the kernel identifies as corrupted. diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c index 440960110a42..b43d0bd42762 100644 --- a/fs/proc/meminfo.c +++ b/fs/proc/meminfo.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -131,6 +132,18 @@ static int meminfo_proc_show(struct seq_file *m, void *v) show_val_kb(m, "VmallocChunk: ", 0ul); show_val_kb(m, "Percpu: ", pcpu_nr_pages()); +#ifdef CONFIG_MEMTEST + if (early_memtest_done) { + unsigned long early_memtest_bad_size_kb; + + early_memtest_bad_size_kb = early_memtest_bad_size>>10; + if (early_memtest_bad_size && !early_memtest_bad_size_kb) + early_memtest_bad_size_kb = 1; + /* When 0 is reported, it means there actually was a successful test */ + seq_printf(m, "EarlyMemtestBad: %5lu kB\n", early_memtest_bad_size_kb); + } +#endif + #ifdef CONFIG_MEMORY_FAILURE seq_printf(m, "HardwareCorrupted: %5lu kB\n", atomic_long_read(&num_poisoned_pages) << (PAGE_SHIFT - 10)); diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 50ad19662a32..f82ee3fac1cd 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -597,6 +597,8 @@ extern int hashdist; /* Distribute hashes across NUMA nodes? */ #endif #ifdef CONFIG_MEMTEST +extern phys_addr_t early_memtest_bad_size; /* Size of faulty ram found by memtest */ +extern bool early_memtest_done; /* Was early memtest done? */ extern void early_memtest(phys_addr_t start, phys_addr_t end); #else static inline void early_memtest(phys_addr_t start, phys_addr_t end) diff --git a/mm/memtest.c b/mm/memtest.c index f53ace709ccd..57149dfee438 100644 --- a/mm/memtest.c +++ b/mm/memtest.c @@ -4,6 +4,9 @@ #include #include +bool early_memtest_done; +phys_addr_t early_memtest_bad_size; + static u64 patterns[] __initdata = { /* The first entry has to be 0 to leave memtest with zeroed memory */ 0, @@ -30,6 +33,7 @@ static void __init reserve_bad_mem(u64 pattern, phys_addr_t start_bad, phys_addr pr_info(" %016llx bad mem addr %pa - %pa reserved\n", cpu_to_be64(pattern), &start_bad, &end_bad); memblock_reserve(start_bad, end_bad - start_bad); + early_memtest_bad_size += (end_bad - start_bad); } static void __init memtest(u64 pattern, phys_addr_t start_phys, phys_addr_t size) @@ -61,6 +65,8 @@ static void __init memtest(u64 pattern, phys_addr_t start_phys, phys_addr_t size } if (start_bad) reserve_bad_mem(pattern, start_bad, last_bad + incr); + + early_memtest_done = true; } static void __init do_one_pass(u64 pattern, phys_addr_t start, phys_addr_t end) -- cgit v1.2.3 From 28d8b812e97b31231e95864f36a6b32f4b307daa Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Sun, 12 Mar 2023 23:40:13 +0000 Subject: mm: remove unused vmf_insert_mixed_prot() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch series "Remove drm/ttm-specific mm changes". Functionality was added specifically for the DRM TTM driver to support mapping memory for VM_MIXEDMAP VMAs with customised protection flags, however this has now been rolled back as issues were found with this approach. This series removes the mm changes too, retaining some of the useful comments. This patch (of 3): The sole user of vmf_insert_mixed_prot(), the drm ttm module, stopped using this in commit f91142c62161 ("drm/ttm: nuke VM_MIXEDMAP on BO mappings v3") citing use of VM_MIXEDMAP in this case being terribly broken. Remove this now-dead code and references to it, but retain the useful description of the prot != vma->vm_page_prot case, moving it to vmf_insert_pfn_prot() instead. Link: https://lkml.kernel.org/r/cover.1678661628.git.lstoakes@gmail.com Link: https://lkml.kernel.org/r/a069644388e6f1593a7020d15840e6fc9f39bcaf.1678661628.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes Cc: Christian König Cc: Dan Williams Cc: Jason Gunthorpe Cc: Kirill A. Shutemov Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Thomas Hellström Cc: Aaron Tomlin Cc: Christoph Lameter Cc: Frederic Weisbecker Cc: Heiko Carstens Cc: Huacai Chen Cc: Marcelo Tosatti Cc: Peter Xu Cc: "Russell King (Oracle)" Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/mm.h | 2 -- include/linux/mm_types.h | 7 +----- mm/memory.c | 57 +++++++++++++++--------------------------------- 3 files changed, 19 insertions(+), 47 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index c3abad7e6ccb..55d02356146c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3179,8 +3179,6 @@ vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, pgprot_t pgprot); vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn); -vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr, - pfn_t pfn, pgprot_t pgprot); vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn); int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len); diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 0722859c3647..651a5c256732 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -485,12 +485,7 @@ struct vm_area_struct { within vm_mm. */ struct mm_struct *vm_mm; /* The address space we belong to. */ - - /* - * Access permissions of this VMA. - * See vmf_insert_mixed_prot() for discussion. - */ - pgprot_t vm_page_prot; + pgprot_t vm_page_prot; /* Access permissions of this VMA. */ /* * Flags, see mm.h. diff --git a/mm/memory.c b/mm/memory.c index 0ee13d3de88c..7716f2cc4b68 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2165,8 +2165,20 @@ out_unlock: * vmf_insert_pfn_prot should only be used if using multiple VMAs is * impractical. * - * See vmf_insert_mixed_prot() for a discussion of the implication of using - * a value of @pgprot different from that of @vma->vm_page_prot. + * pgprot typically only differs from @vma->vm_page_prot when drivers set + * caching- and encryption bits different than those of @vma->vm_page_prot, + * because the caching- or encryption mode may not be known at mmap() time. + * + * This is ok as long as @vma->vm_page_prot is not used by the core vm + * to set caching and encryption bits for those vmas (except for COW pages). + * This is ensured by core vm only modifying these page table entries using + * functions that don't touch caching- or encryption bits, using pte_modify() + * if needed. (See for example mprotect()). + * + * Also when new page-table entries are created, this is only done using the + * fault() callback, and never using the value of vma->vm_page_prot, + * except for page-table entries that point to anonymous pages as the result + * of COW. * * Context: Process context. May allocate using %GFP_KERNEL. * Return: vm_fault_t value. @@ -2241,9 +2253,9 @@ static bool vm_mixed_ok(struct vm_area_struct *vma, pfn_t pfn) } static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma, - unsigned long addr, pfn_t pfn, pgprot_t pgprot, - bool mkwrite) + unsigned long addr, pfn_t pfn, bool mkwrite) { + pgprot_t pgprot = vma->vm_page_prot; int err; BUG_ON(!vm_mixed_ok(vma, pfn)); @@ -2286,43 +2298,10 @@ static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma, return VM_FAULT_NOPAGE; } -/** - * vmf_insert_mixed_prot - insert single pfn into user vma with specified pgprot - * @vma: user vma to map to - * @addr: target user address of this page - * @pfn: source kernel pfn - * @pgprot: pgprot flags for the inserted page - * - * This is exactly like vmf_insert_mixed(), except that it allows drivers - * to override pgprot on a per-page basis. - * - * Typically this function should be used by drivers to set caching- and - * encryption bits different than those of @vma->vm_page_prot, because - * the caching- or encryption mode may not be known at mmap() time. - * This is ok as long as @vma->vm_page_prot is not used by the core vm - * to set caching and encryption bits for those vmas (except for COW pages). - * This is ensured by core vm only modifying these page table entries using - * functions that don't touch caching- or encryption bits, using pte_modify() - * if needed. (See for example mprotect()). - * Also when new page-table entries are created, this is only done using the - * fault() callback, and never using the value of vma->vm_page_prot, - * except for page-table entries that point to anonymous pages as the result - * of COW. - * - * Context: Process context. May allocate using %GFP_KERNEL. - * Return: vm_fault_t value. - */ -vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr, - pfn_t pfn, pgprot_t pgprot) -{ - return __vm_insert_mixed(vma, addr, pfn, pgprot, false); -} -EXPORT_SYMBOL(vmf_insert_mixed_prot); - vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn) { - return __vm_insert_mixed(vma, addr, pfn, vma->vm_page_prot, false); + return __vm_insert_mixed(vma, addr, pfn, false); } EXPORT_SYMBOL(vmf_insert_mixed); @@ -2334,7 +2313,7 @@ EXPORT_SYMBOL(vmf_insert_mixed); vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn) { - return __vm_insert_mixed(vma, addr, pfn, vma->vm_page_prot, true); + return __vm_insert_mixed(vma, addr, pfn, true); } EXPORT_SYMBOL(vmf_insert_mixed_mkwrite); -- cgit v1.2.3 From 7b806d229ef151c2997c041b791dfa89593e0e1b Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Sun, 12 Mar 2023 23:40:14 +0000 Subject: mm: remove vmf_insert_pfn_xxx_prot() for huge page-table entries MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This functionality's sole user, the drm ttm module, removed support for it in commit 0d979509539e ("drm/ttm: remove ttm_bo_vm_insert_huge()") as the whole approach is currently unworkable without a PMD/PUD special bit and updates to GUP. Link: https://lkml.kernel.org/r/604c2ad79659d4b8a6e3e1611c6219d5d3233988.1678661628.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes Cc: Christian König Cc: Dan Williams Cc: Jason Gunthorpe Cc: Kirill A. Shutemov Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Thomas Hellström Cc: Aaron Tomlin Cc: Christoph Lameter Cc: Frederic Weisbecker Cc: Heiko Carstens Cc: Huacai Chen Cc: Marcelo Tosatti Cc: Peter Xu Cc: "Russell King (Oracle)" Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/huge_mm.h | 39 ++------------------------------------- mm/huge_memory.c | 31 +++++++++++++------------------ 2 files changed, 15 insertions(+), 55 deletions(-) (limited to 'include') diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 9a3a3af2dd80..20284387b841 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -39,44 +39,9 @@ bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr, int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, pgprot_t newprot, unsigned long cp_flags); -vm_fault_t vmf_insert_pfn_pmd_prot(struct vm_fault *vmf, pfn_t pfn, - pgprot_t pgprot, bool write); -/** - * vmf_insert_pfn_pmd - insert a pmd size pfn - * @vmf: Structure describing the fault - * @pfn: pfn to insert - * @pgprot: page protection to use - * @write: whether it's a write fault - * - * Insert a pmd size pfn. See vmf_insert_pfn() for additional info. - * - * Return: vm_fault_t value. - */ -static inline vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, - bool write) -{ - return vmf_insert_pfn_pmd_prot(vmf, pfn, vmf->vma->vm_page_prot, write); -} -vm_fault_t vmf_insert_pfn_pud_prot(struct vm_fault *vmf, pfn_t pfn, - pgprot_t pgprot, bool write); - -/** - * vmf_insert_pfn_pud - insert a pud size pfn - * @vmf: Structure describing the fault - * @pfn: pfn to insert - * @pgprot: page protection to use - * @write: whether it's a write fault - * - * Insert a pud size pfn. See vmf_insert_pfn() for additional info. - * - * Return: vm_fault_t value. - */ -static inline vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, - bool write) -{ - return vmf_insert_pfn_pud_prot(vmf, pfn, vmf->vma->vm_page_prot, write); -} +vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write); +vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write); enum transparent_hugepage_flag { TRANSPARENT_HUGEPAGE_UNSUPPORTED, diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 1df386d13d24..81a5689806af 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -885,23 +885,20 @@ out_unlock: } /** - * vmf_insert_pfn_pmd_prot - insert a pmd size pfn + * vmf_insert_pfn_pmd - insert a pmd size pfn * @vmf: Structure describing the fault * @pfn: pfn to insert - * @pgprot: page protection to use * @write: whether it's a write fault * - * Insert a pmd size pfn. See vmf_insert_pfn() for additional info and - * also consult the vmf_insert_mixed_prot() documentation when - * @pgprot != @vmf->vma->vm_page_prot. + * Insert a pmd size pfn. See vmf_insert_pfn() for additional info. * * Return: vm_fault_t value. */ -vm_fault_t vmf_insert_pfn_pmd_prot(struct vm_fault *vmf, pfn_t pfn, - pgprot_t pgprot, bool write) +vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write) { unsigned long addr = vmf->address & PMD_MASK; struct vm_area_struct *vma = vmf->vma; + pgprot_t pgprot = vma->vm_page_prot; pgtable_t pgtable = NULL; /* @@ -929,7 +926,7 @@ vm_fault_t vmf_insert_pfn_pmd_prot(struct vm_fault *vmf, pfn_t pfn, insert_pfn_pmd(vma, addr, vmf->pmd, pfn, pgprot, write, pgtable); return VM_FAULT_NOPAGE; } -EXPORT_SYMBOL_GPL(vmf_insert_pfn_pmd_prot); +EXPORT_SYMBOL_GPL(vmf_insert_pfn_pmd); #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD static pud_t maybe_pud_mkwrite(pud_t pud, struct vm_area_struct *vma) @@ -940,9 +937,10 @@ static pud_t maybe_pud_mkwrite(pud_t pud, struct vm_area_struct *vma) } static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, - pud_t *pud, pfn_t pfn, pgprot_t prot, bool write) + pud_t *pud, pfn_t pfn, bool write) { struct mm_struct *mm = vma->vm_mm; + pgprot_t prot = vma->vm_page_prot; pud_t entry; spinlock_t *ptl; @@ -976,23 +974,20 @@ out_unlock: } /** - * vmf_insert_pfn_pud_prot - insert a pud size pfn + * vmf_insert_pfn_pud - insert a pud size pfn * @vmf: Structure describing the fault * @pfn: pfn to insert - * @pgprot: page protection to use * @write: whether it's a write fault * - * Insert a pud size pfn. See vmf_insert_pfn() for additional info and - * also consult the vmf_insert_mixed_prot() documentation when - * @pgprot != @vmf->vma->vm_page_prot. + * Insert a pud size pfn. See vmf_insert_pfn() for additional info. * * Return: vm_fault_t value. */ -vm_fault_t vmf_insert_pfn_pud_prot(struct vm_fault *vmf, pfn_t pfn, - pgprot_t pgprot, bool write) +vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write) { unsigned long addr = vmf->address & PUD_MASK; struct vm_area_struct *vma = vmf->vma; + pgprot_t pgprot = vma->vm_page_prot; /* * If we had pud_special, we could avoid all these restrictions, @@ -1010,10 +1005,10 @@ vm_fault_t vmf_insert_pfn_pud_prot(struct vm_fault *vmf, pfn_t pfn, track_pfn_insert(vma, &pgprot, pfn); - insert_pfn_pud(vma, addr, vmf->pud, pfn, pgprot, write); + insert_pfn_pud(vma, addr, vmf->pud, pfn, write); return VM_FAULT_NOPAGE; } -EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud_prot); +EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud); #endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ static void touch_pmd(struct vm_area_struct *vma, unsigned long addr, -- cgit v1.2.3 From 3f6dac0fd1b83178137e7b4e722d8f29612cbec1 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Tue, 21 Mar 2023 03:24:15 +0300 Subject: mm/page_alloc: make deferred page init free pages in MAX_ORDER blocks Normal page init path frees pages during the boot in MAX_ORDER chunks, but deferred page init path does it in pageblock blocks. Change deferred page init path to work in MAX_ORDER blocks. For cases when MAX_ORDER is larger than pageblock, set migrate type to MIGRATE_MOVABLE for all pageblocks covered by the page. Link: https://lkml.kernel.org/r/20230321002415.20843-1-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Reviewed-by: Vlastimil Babka Acked-by: David Hildenbrand Acked-by: Mel Gorman Acked-by: Mike Rapoport (IBM) Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 2 ++ mm/mm_init.c | 19 ++++++++++--------- 2 files changed, 12 insertions(+), 9 deletions(-) (limited to 'include') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 2d3d78d01283..2d22e47dc1eb 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -32,6 +32,8 @@ #endif #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER) +#define IS_MAX_ORDER_ALIGNED(pfn) IS_ALIGNED(pfn, MAX_ORDER_NR_PAGES) + /* * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed * costly to service. That is between allocation orders which should diff --git a/mm/mm_init.c b/mm/mm_init.c index 53fb8e9d1e3b..c88fbe74137c 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -1951,9 +1951,10 @@ static void __init deferred_free_range(unsigned long pfn, page = pfn_to_page(pfn); /* Free a large naturally-aligned chunk if possible */ - if (nr_pages == pageblock_nr_pages && pageblock_aligned(pfn)) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - __free_pages_core(page, pageblock_order); + if (nr_pages == MAX_ORDER_NR_PAGES && IS_MAX_ORDER_ALIGNED(pfn)) { + for (i = 0; i < nr_pages; i += pageblock_nr_pages) + set_pageblock_migratetype(page + i, MIGRATE_MOVABLE); + __free_pages_core(page, MAX_ORDER); return; } @@ -1977,19 +1978,19 @@ static inline void __init pgdat_init_report_one_done(void) /* * Returns true if page needs to be initialized or freed to buddy allocator. * - * We check if a current large page is valid by only checking the validity + * We check if a current MAX_ORDER block is valid by only checking the validity * of the head pfn. */ static inline bool __init deferred_pfn_valid(unsigned long pfn) { - if (pageblock_aligned(pfn) && !pfn_valid(pfn)) + if (IS_MAX_ORDER_ALIGNED(pfn) && !pfn_valid(pfn)) return false; return true; } /* * Free pages to buddy allocator. Try to free aligned pages in - * pageblock_nr_pages sizes. + * MAX_ORDER_NR_PAGES sizes. */ static void __init deferred_free_pages(unsigned long pfn, unsigned long end_pfn) @@ -2000,7 +2001,7 @@ static void __init deferred_free_pages(unsigned long pfn, if (!deferred_pfn_valid(pfn)) { deferred_free_range(pfn - nr_free, nr_free); nr_free = 0; - } else if (pageblock_aligned(pfn)) { + } else if (IS_MAX_ORDER_ALIGNED(pfn)) { deferred_free_range(pfn - nr_free, nr_free); nr_free = 1; } else { @@ -2013,7 +2014,7 @@ static void __init deferred_free_pages(unsigned long pfn, /* * Initialize struct pages. We minimize pfn page lookups and scheduler checks - * by performing it only once every pageblock_nr_pages. + * by performing it only once every MAX_ORDER_NR_PAGES. * Return number of pages initialized. */ static unsigned long __init deferred_init_pages(struct zone *zone, @@ -2029,7 +2030,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone, if (!deferred_pfn_valid(pfn)) { page = NULL; continue; - } else if (!page || pageblock_aligned(pfn)) { + } else if (!page || IS_MAX_ORDER_ALIGNED(pfn)) { page = pfn_to_page(pfn); } else { page++; -- cgit v1.2.3 From 4f80818b4a58c9458dce0df7cce9abe107da445e Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Wed, 22 Mar 2023 18:57:03 +0000 Subject: iov_iter: add copy_page_to_iter_nofault() Provide a means to copy a page to user space from an iterator, aborting if a page fault would occur. This supports compound pages, but may be passed a tail page with an offset extending further into the compound page, so we cannot pass a folio. This allows for this function to be called from atomic context and _try_ to user pages if they are faulted in, aborting if not. The function does not use _copy_to_iter() in order to not specify might_fault(), this is similar to copy_page_from_iter_atomic(). This is being added in order that an iteratable form of vread() can be implemented while holding spinlocks. Link: https://lkml.kernel.org/r/19734729defb0f498a76bdec1bef3ac48a3af3e8.1679511146.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes Reviewed-by: Baoquan He Cc: Alexander Viro Cc: David Hildenbrand Cc: Jens Axboe Cc: Jiri Olsa Cc: Liu Shixin Cc: Matthew Wilcox (Oracle) Cc: Uladzislau Rezki (Sony) Signed-off-by: Andrew Morton --- include/linux/uio.h | 2 ++ lib/iov_iter.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+) (limited to 'include') diff --git a/include/linux/uio.h b/include/linux/uio.h index 27e3fd942960..29eb18bb6feb 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -173,6 +173,8 @@ static inline size_t copy_folio_to_iter(struct folio *folio, size_t offset, { return copy_page_to_iter(&folio->page, offset, bytes, i); } +size_t copy_page_to_iter_nofault(struct page *page, unsigned offset, + size_t bytes, struct iov_iter *i); static __always_inline __must_check size_t copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i) diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 274014e4eafe..34dd6bdf2fba 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -172,6 +172,18 @@ static int copyout(void __user *to, const void *from, size_t n) return n; } +static int copyout_nofault(void __user *to, const void *from, size_t n) +{ + long res; + + if (should_fail_usercopy()) + return n; + + res = copy_to_user_nofault(to, from, n); + + return res < 0 ? n : res; +} + static int copyin(void *to, const void __user *from, size_t n) { size_t res = n; @@ -734,6 +746,42 @@ size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes, } EXPORT_SYMBOL(copy_page_to_iter); +size_t copy_page_to_iter_nofault(struct page *page, unsigned offset, size_t bytes, + struct iov_iter *i) +{ + size_t res = 0; + + if (!page_copy_sane(page, offset, bytes)) + return 0; + if (WARN_ON_ONCE(i->data_source)) + return 0; + if (unlikely(iov_iter_is_pipe(i))) + return copy_page_to_iter_pipe(page, offset, bytes, i); + page += offset / PAGE_SIZE; // first subpage + offset %= PAGE_SIZE; + while (1) { + void *kaddr = kmap_local_page(page); + size_t n = min(bytes, (size_t)PAGE_SIZE - offset); + + iterate_and_advance(i, n, base, len, off, + copyout_nofault(base, kaddr + offset + off, len), + memcpy(base, kaddr + offset + off, len) + ) + kunmap_local(kaddr); + res += n; + bytes -= n; + if (!bytes || !n) + break; + offset += n; + if (offset == PAGE_SIZE) { + page++; + offset = 0; + } + } + return res; +} +EXPORT_SYMBOL(copy_page_to_iter_nofault); + size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes, struct iov_iter *i) { -- cgit v1.2.3 From 4c91c07c93bbbdd7f2d9de2beb7ee5c2a48ad8e7 Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Wed, 22 Mar 2023 18:57:04 +0000 Subject: mm: vmalloc: convert vread() to vread_iter() Having previously laid the foundation for converting vread() to an iterator function, pull the trigger and do so. This patch attempts to provide minimal refactoring and to reflect the existing logic as best we can, for example we continue to zero portions of memory not read, as before. Overall, there should be no functional difference other than a performance improvement in /proc/kcore access to vmalloc regions. Now we have eliminated the need for a bounce buffer in read_kcore_iter(), we dispense with it, and try to write to user memory optimistically but with faults disabled via copy_page_to_iter_nofault(). We already have preemption disabled by holding a spin lock. We continue faulting in until the operation is complete. Additionally, we must account for the fact that at any point a copy may fail (most likely due to a fault not being able to occur), we exit indicating fewer bytes retrieved than expected. [sfr@canb.auug.org.au: fix sparc64 warning] Link: https://lkml.kernel.org/r/20230320144721.663280c3@canb.auug.org.au [lstoakes@gmail.com: redo Stephen's sparc build fix] Link: https://lkml.kernel.org/r/8506cbc667c39205e65a323f750ff9c11a463798.1679566220.git.lstoakes@gmail.com [akpm@linux-foundation.org: unbreak uio.h includes] Link: https://lkml.kernel.org/r/941f88bc5ab928e6656e1e2593b91bf0f8c81e1b.1679511146.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes Signed-off-by: Stephen Rothwell Reviewed-by: Baoquan He Cc: Alexander Viro Cc: David Hildenbrand Cc: Jens Axboe Cc: Jiri Olsa Cc: Liu Shixin Cc: Matthew Wilcox (Oracle) Cc: Uladzislau Rezki (Sony) Signed-off-by: Andrew Morton --- fs/proc/kcore.c | 44 ++++----- include/linux/vmalloc.h | 3 +- mm/nommu.c | 10 +-- mm/vmalloc.c | 235 ++++++++++++++++++++++++++++++------------------ 4 files changed, 177 insertions(+), 115 deletions(-) (limited to 'include') diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index 08b795fd80b4..25b44b303b35 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -307,13 +307,9 @@ static void append_kcore_note(char *notes, size_t *i, const char *name, *i = ALIGN(*i + descsz, 4); } -static ssize_t -read_kcore_iter(struct kiocb *iocb, struct iov_iter *iter) +static ssize_t read_kcore_iter(struct kiocb *iocb, struct iov_iter *iter) { - struct file *file = iocb->ki_filp; - char *buf = file->private_data; loff_t *fpos = &iocb->ki_pos; - size_t phdrs_offset, notes_offset, data_offset; size_t page_offline_frozen = 1; size_t phdrs_len, notes_len; @@ -507,13 +503,30 @@ read_kcore_iter(struct kiocb *iocb, struct iov_iter *iter) switch (m->type) { case KCORE_VMALLOC: - vread(buf, (char *)start, tsz); - /* we have to zero-fill user buffer even if no read */ - if (copy_to_iter(buf, tsz, iter) != tsz) { - ret = -EFAULT; - goto out; + { + const char *src = (char *)start; + size_t read = 0, left = tsz; + + /* + * vmalloc uses spinlocks, so we optimistically try to + * read memory. If this fails, fault pages in and try + * again until we are done. + */ + while (true) { + read += vread_iter(iter, src, left); + if (read == tsz) + break; + + src += read; + left -= read; + + if (fault_in_iov_iter_writeable(iter, left)) { + ret = -EFAULT; + goto out; + } } break; + } case KCORE_USER: /* User page is handled prior to normal kernel page: */ if (copy_to_iter((char *)start, tsz, iter) != tsz) { @@ -582,10 +595,6 @@ static int open_kcore(struct inode *inode, struct file *filp) if (ret) return ret; - filp->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!filp->private_data) - return -ENOMEM; - if (kcore_need_update) kcore_update_ram(); if (i_size_read(inode) != proc_root_kcore->size) { @@ -596,16 +605,9 @@ static int open_kcore(struct inode *inode, struct file *filp) return 0; } -static int release_kcore(struct inode *inode, struct file *file) -{ - kfree(file->private_data); - return 0; -} - static const struct proc_ops kcore_proc_ops = { .proc_read_iter = read_kcore_iter, .proc_open = open_kcore, - .proc_release = release_kcore, .proc_lseek = default_llseek, }; diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 351fc7697214..c720be70c8dd 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -14,6 +14,7 @@ struct vm_area_struct; /* vma defining user mapping in mm_types.h */ struct notifier_block; /* in notifier.h */ +struct iov_iter; /* in uio.h */ /* bits in flags of vmalloc's vm_struct below */ #define VM_IOREMAP 0x00000001 /* ioremap() and friends */ @@ -247,7 +248,7 @@ static inline void set_vm_flush_reset_perms(void *addr) #endif /* for /proc/kcore */ -extern long vread(char *buf, char *addr, unsigned long count); +extern long vread_iter(struct iov_iter *iter, const char *addr, size_t count); /* * Internals. Don't use.. diff --git a/mm/nommu.c b/mm/nommu.c index 57ba243c6a37..f670d9979a26 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -36,6 +36,7 @@ #include #include +#include #include #include #include @@ -198,14 +199,13 @@ unsigned long vmalloc_to_pfn(const void *addr) } EXPORT_SYMBOL(vmalloc_to_pfn); -long vread(char *buf, char *addr, unsigned long count) +long vread_iter(struct iov_iter *iter, const char *addr, size_t count) { /* Don't allow overflow */ - if ((unsigned long) buf + count < count) - count = -(unsigned long) buf; + if ((unsigned long) addr + count < count) + count = -(unsigned long) addr; - memcpy(buf, addr, count); - return count; + return copy_to_iter(addr, count, iter); } /* diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 978194dc2bb8..5291c6f02cf7 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -33,11 +33,11 @@ #include #include #include +#include #include #include #include #include -#include #include #include #include @@ -3442,62 +3442,96 @@ void *vmalloc_32_user(unsigned long size) EXPORT_SYMBOL(vmalloc_32_user); /* - * small helper routine , copy contents to buf from addr. - * If the page is not present, fill zero. + * Atomically zero bytes in the iterator. + * + * Returns the number of zeroed bytes. */ +static size_t zero_iter(struct iov_iter *iter, size_t count) +{ + size_t remains = count; + + while (remains > 0) { + size_t num, copied; + + num = remains < PAGE_SIZE ? remains : PAGE_SIZE; + copied = copy_page_to_iter_nofault(ZERO_PAGE(0), 0, num, iter); + remains -= copied; + + if (copied < num) + break; + } -static int aligned_vread(char *buf, char *addr, unsigned long count) + return count - remains; +} + +/* + * small helper routine, copy contents to iter from addr. + * If the page is not present, fill zero. + * + * Returns the number of copied bytes. + */ +static size_t aligned_vread_iter(struct iov_iter *iter, + const char *addr, size_t count) { - struct page *p; - int copied = 0; + size_t remains = count; + struct page *page; - while (count) { + while (remains > 0) { unsigned long offset, length; + size_t copied = 0; offset = offset_in_page(addr); length = PAGE_SIZE - offset; - if (length > count) - length = count; - p = vmalloc_to_page(addr); + if (length > remains) + length = remains; + page = vmalloc_to_page(addr); /* - * To do safe access to this _mapped_ area, we need - * lock. But adding lock here means that we need to add - * overhead of vmalloc()/vfree() calls for this _debug_ - * interface, rarely used. Instead of that, we'll use - * kmap() and get small overhead in this access function. + * To do safe access to this _mapped_ area, we need lock. But + * adding lock here means that we need to add overhead of + * vmalloc()/vfree() calls for this _debug_ interface, rarely + * used. Instead of that, we'll use an local mapping via + * copy_page_to_iter_nofault() and accept a small overhead in + * this access function. */ - if (p) { - /* We can expect USER0 is not used -- see vread() */ - void *map = kmap_atomic(p); - memcpy(buf, map + offset, length); - kunmap_atomic(map); - } else - memset(buf, 0, length); + if (page) + copied = copy_page_to_iter_nofault(page, offset, + length, iter); + else + copied = zero_iter(iter, length); - addr += length; - buf += length; - copied += length; - count -= length; + addr += copied; + remains -= copied; + + if (copied != length) + break; } - return copied; + + return count - remains; } -static void vmap_ram_vread(char *buf, char *addr, int count, unsigned long flags) +/* + * Read from a vm_map_ram region of memory. + * + * Returns the number of copied bytes. + */ +static size_t vmap_ram_vread_iter(struct iov_iter *iter, const char *addr, + size_t count, unsigned long flags) { char *start; struct vmap_block *vb; unsigned long offset; - unsigned int rs, re, n; + unsigned int rs, re; + size_t remains, n; /* * If it's area created by vm_map_ram() interface directly, but * not further subdividing and delegating management to vmap_block, * handle it here. */ - if (!(flags & VMAP_BLOCK)) { - aligned_vread(buf, addr, count); - return; - } + if (!(flags & VMAP_BLOCK)) + return aligned_vread_iter(iter, addr, count); + + remains = count; /* * Area is split into regions and tracked with vmap_block, read out @@ -3505,50 +3539,64 @@ static void vmap_ram_vread(char *buf, char *addr, int count, unsigned long flags */ vb = xa_load(&vmap_blocks, addr_to_vb_idx((unsigned long)addr)); if (!vb) - goto finished; + goto finished_zero; spin_lock(&vb->lock); if (bitmap_empty(vb->used_map, VMAP_BBMAP_BITS)) { spin_unlock(&vb->lock); - goto finished; + goto finished_zero; } + for_each_set_bitrange(rs, re, vb->used_map, VMAP_BBMAP_BITS) { - if (!count) - break; + size_t copied; + + if (remains == 0) + goto finished; + start = vmap_block_vaddr(vb->va->va_start, rs); - while (addr < start) { - if (count == 0) - goto unlock; - *buf = '\0'; - buf++; - addr++; - count--; + + if (addr < start) { + size_t to_zero = min_t(size_t, start - addr, remains); + size_t zeroed = zero_iter(iter, to_zero); + + addr += zeroed; + remains -= zeroed; + + if (remains == 0 || zeroed != to_zero) + goto finished; } + /*it could start reading from the middle of used region*/ offset = offset_in_page(addr); n = ((re - rs + 1) << PAGE_SHIFT) - offset; - if (n > count) - n = count; - aligned_vread(buf, start+offset, n); + if (n > remains) + n = remains; + + copied = aligned_vread_iter(iter, start + offset, n); - buf += n; - addr += n; - count -= n; + addr += copied; + remains -= copied; + + if (copied != n) + goto finished; } -unlock: + spin_unlock(&vb->lock); -finished: +finished_zero: /* zero-fill the left dirty or free regions */ - if (count) - memset(buf, 0, count); + return count - remains + zero_iter(iter, remains); +finished: + /* We couldn't copy/zero everything */ + spin_unlock(&vb->lock); + return count - remains; } /** - * vread() - read vmalloc area in a safe way. - * @buf: buffer for reading data - * @addr: vm address. - * @count: number of bytes to be read. + * vread_iter() - read vmalloc area in a safe way to an iterator. + * @iter: the iterator to which data should be written. + * @addr: vm address. + * @count: number of bytes to be read. * * This function checks that addr is a valid vmalloc'ed area, and * copy data from that area to a given buffer. If the given memory range @@ -3568,13 +3616,12 @@ finished: * (same number as @count) or %0 if [addr...addr+count) doesn't * include any intersection with valid vmalloc area */ -long vread(char *buf, char *addr, unsigned long count) +long vread_iter(struct iov_iter *iter, const char *addr, size_t count) { struct vmap_area *va; struct vm_struct *vm; - char *vaddr, *buf_start = buf; - unsigned long buflen = count; - unsigned long n, size, flags; + char *vaddr; + size_t n, size, flags, remains; addr = kasan_reset_tag(addr); @@ -3582,18 +3629,22 @@ long vread(char *buf, char *addr, unsigned long count) if ((unsigned long) addr + count < count) count = -(unsigned long) addr; + remains = count; + spin_lock(&vmap_area_lock); va = find_vmap_area_exceed_addr((unsigned long)addr); if (!va) - goto finished; + goto finished_zero; /* no intersects with alive vmap_area */ - if ((unsigned long)addr + count <= va->va_start) - goto finished; + if ((unsigned long)addr + remains <= va->va_start) + goto finished_zero; list_for_each_entry_from(va, &vmap_area_list, list) { - if (!count) - break; + size_t copied; + + if (remains == 0) + goto finished; vm = va->vm; flags = va->flags & VMAP_FLAGS_MASK; @@ -3608,6 +3659,7 @@ long vread(char *buf, char *addr, unsigned long count) if (vm && (vm->flags & VM_UNINITIALIZED)) continue; + /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */ smp_rmb(); @@ -3616,38 +3668,45 @@ long vread(char *buf, char *addr, unsigned long count) if (addr >= vaddr + size) continue; - while (addr < vaddr) { - if (count == 0) + + if (addr < vaddr) { + size_t to_zero = min_t(size_t, vaddr - addr, remains); + size_t zeroed = zero_iter(iter, to_zero); + + addr += zeroed; + remains -= zeroed; + + if (remains == 0 || zeroed != to_zero) goto finished; - *buf = '\0'; - buf++; - addr++; - count--; } + n = vaddr + size - addr; - if (n > count) - n = count; + if (n > remains) + n = remains; if (flags & VMAP_RAM) - vmap_ram_vread(buf, addr, n, flags); + copied = vmap_ram_vread_iter(iter, addr, n, flags); else if (!(vm->flags & VM_IOREMAP)) - aligned_vread(buf, addr, n); + copied = aligned_vread_iter(iter, addr, n); else /* IOREMAP area is treated as memory hole */ - memset(buf, 0, n); - buf += n; - addr += n; - count -= n; + copied = zero_iter(iter, n); + + addr += copied; + remains -= copied; + + if (copied != n) + goto finished; } -finished: - spin_unlock(&vmap_area_lock); - if (buf == buf_start) - return 0; +finished_zero: + spin_unlock(&vmap_area_lock); /* zero-fill memory holes */ - if (buf != buf_start + buflen) - memset(buf, 0, buflen - (buf - buf_start)); + return count - remains + zero_iter(iter, remains); +finished: + /* Nothing remains, or We couldn't copy/zero everything. */ + spin_unlock(&vmap_area_lock); - return buflen; + return count - remains; } /** -- cgit v1.2.3 From c710fac6bfc8c2bcfedbaba27e31524c98eb6188 Mon Sep 17 00:00:00 2001 From: Wenchao Hao Date: Thu, 23 Mar 2023 19:41:36 +0800 Subject: trace: cma: remove unnecessary event class cma_alloc_class After commit cb6c33d4dc09 ("cma: tracing: print alloc result in trace_cma_alloc_finish"), cma_alloc_class has only one event which is cma_alloc_busy_retry. So we can remove the cma_alloc_class. Link: https://lkml.kernel.org/r/20230323114136.177677-1-haowenchao2@huawei.com Signed-off-by: Wenchao Hao Acked-by: Steven Rostedt (Google) Cc: Feilong Lin Cc: Hongxiang Lou Cc: Masami Hiramatsu Signed-off-by: Andrew Morton --- include/trace/events/cma.h | 58 ++++++++++++++++++++-------------------------- 1 file changed, 25 insertions(+), 33 deletions(-) (limited to 'include') diff --git a/include/trace/events/cma.h b/include/trace/events/cma.h index ef75ea606ab2..25103e67737c 100644 --- a/include/trace/events/cma.h +++ b/include/trace/events/cma.h @@ -8,37 +8,6 @@ #include #include -DECLARE_EVENT_CLASS(cma_alloc_class, - - TP_PROTO(const char *name, unsigned long pfn, const struct page *page, - unsigned long count, unsigned int align), - - TP_ARGS(name, pfn, page, count, align), - - TP_STRUCT__entry( - __string(name, name) - __field(unsigned long, pfn) - __field(const struct page *, page) - __field(unsigned long, count) - __field(unsigned int, align) - ), - - TP_fast_assign( - __assign_str(name, name); - __entry->pfn = pfn; - __entry->page = page; - __entry->count = count; - __entry->align = align; - ), - - TP_printk("name=%s pfn=0x%lx page=%p count=%lu align=%u", - __get_str(name), - __entry->pfn, - __entry->page, - __entry->count, - __entry->align) -); - TRACE_EVENT(cma_release, TP_PROTO(const char *name, unsigned long pfn, const struct page *page, @@ -125,12 +94,35 @@ TRACE_EVENT(cma_alloc_finish, __entry->errorno) ); -DEFINE_EVENT(cma_alloc_class, cma_alloc_busy_retry, +TRACE_EVENT(cma_alloc_busy_retry, TP_PROTO(const char *name, unsigned long pfn, const struct page *page, unsigned long count, unsigned int align), - TP_ARGS(name, pfn, page, count, align) + TP_ARGS(name, pfn, page, count, align), + + TP_STRUCT__entry( + __string(name, name) + __field(unsigned long, pfn) + __field(const struct page *, page) + __field(unsigned long, count) + __field(unsigned int, align) + ), + + TP_fast_assign( + __assign_str(name, name); + __entry->pfn = pfn; + __entry->page = page; + __entry->count = count; + __entry->align = align; + ), + + TP_printk("name=%s pfn=0x%lx page=%p count=%lu align=%u", + __get_str(name), + __entry->pfn, + __entry->page, + __entry->count, + __entry->align) ); #endif /* _TRACE_CMA_H */ -- cgit v1.2.3 From 20cce633f4254cc0df39665449726e3172518f6c Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Mon, 27 Feb 2023 09:36:09 -0800 Subject: mm: rcu safe VMA freeing This prepares for page faults handling under VMA lock, looking up VMAs under protection of an rcu read lock, instead of the usual mmap read lock. Link: https://lkml.kernel.org/r/20230227173632.3292573-11-surenb@google.com Signed-off-by: Michel Lespinasse Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm_types.h | 13 ++++++++++--- kernel/fork.c | 20 +++++++++++++++++++- 2 files changed, 29 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 651a5c256732..f203e2562e00 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -480,9 +480,16 @@ struct anon_vma_name { struct vm_area_struct { /* The first cache line has the info for VMA tree walking. */ - unsigned long vm_start; /* Our start address within vm_mm. */ - unsigned long vm_end; /* The first byte after our end address - within vm_mm. */ + union { + struct { + /* VMA covers [vm_start; vm_end) addresses within mm */ + unsigned long vm_start; + unsigned long vm_end; + }; +#ifdef CONFIG_PER_VMA_LOCK + struct rcu_head vm_rcu; /* Used for deferred freeing. */ +#endif + }; struct mm_struct *vm_mm; /* The address space we belong to. */ pgprot_t vm_page_prot; /* Access permissions of this VMA. */ diff --git a/kernel/fork.c b/kernel/fork.c index cea99f003f24..93ec6e14bb65 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -479,12 +479,30 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) return new; } -void vm_area_free(struct vm_area_struct *vma) +static void __vm_area_free(struct vm_area_struct *vma) { free_anon_vma_name(vma); kmem_cache_free(vm_area_cachep, vma); } +#ifdef CONFIG_PER_VMA_LOCK +static void vm_area_free_rcu_cb(struct rcu_head *head) +{ + struct vm_area_struct *vma = container_of(head, struct vm_area_struct, + vm_rcu); + __vm_area_free(vma); +} +#endif + +void vm_area_free(struct vm_area_struct *vma) +{ +#ifdef CONFIG_PER_VMA_LOCK + call_rcu(&vma->vm_rcu, vm_area_free_rcu_cb); +#else + __vm_area_free(vma); +#endif +} + static void account_kernel_stack(struct task_struct *tsk, int account) { if (IS_ENABLED(CONFIG_VMAP_STACK)) { -- cgit v1.2.3 From 438b6e12cd603a9416ca7c5462ab75b2a8c4d5b9 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:10 -0800 Subject: mm: move mmap_lock assert function definitions Move mmap_lock assert function definitions up so that they can be used by other mmap_lock routines. Link: https://lkml.kernel.org/r/20230227173632.3292573-12-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mmap_lock.h | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'include') diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h index 96e113e23d04..e49ba91bb1f0 100644 --- a/include/linux/mmap_lock.h +++ b/include/linux/mmap_lock.h @@ -60,6 +60,18 @@ static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write) #endif /* CONFIG_TRACING */ +static inline void mmap_assert_locked(struct mm_struct *mm) +{ + lockdep_assert_held(&mm->mmap_lock); + VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); +} + +static inline void mmap_assert_write_locked(struct mm_struct *mm) +{ + lockdep_assert_held_write(&mm->mmap_lock); + VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); +} + static inline void mmap_init_lock(struct mm_struct *mm) { init_rwsem(&mm->mmap_lock); @@ -150,18 +162,6 @@ static inline void mmap_read_unlock_non_owner(struct mm_struct *mm) up_read_non_owner(&mm->mmap_lock); } -static inline void mmap_assert_locked(struct mm_struct *mm) -{ - lockdep_assert_held(&mm->mmap_lock); - VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); -} - -static inline void mmap_assert_write_locked(struct mm_struct *mm) -{ - lockdep_assert_held_write(&mm->mmap_lock); - VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); -} - static inline int mmap_lock_is_contended(struct mm_struct *mm) { return rwsem_is_contended(&mm->mmap_lock); -- cgit v1.2.3 From 5e31275cc997f8ec5d9e8d65fe9840ebed89db19 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:11 -0800 Subject: mm: add per-VMA lock and helper functions to control it Introduce per-VMA locking. The lock implementation relies on a per-vma and per-mm sequence counters to note exclusive locking: - read lock - (implemented by vma_start_read) requires the vma (vm_lock_seq) and mm (mm_lock_seq) sequence counters to differ. If they match then there must be a vma exclusive lock held somewhere. - read unlock - (implemented by vma_end_read) is a trivial vma->lock unlock. - write lock - (vma_start_write) requires the mmap_lock to be held exclusively and the current mm counter is assigned to the vma counter. This will allow multiple vmas to be locked under a single mmap_lock write lock (e.g. during vma merging). The vma counter is modified under exclusive vma lock. - write unlock - (vma_end_write_all) is a batch release of all vma locks held. It doesn't pair with a specific vma_start_write! It is done before exclusive mmap_lock is released by incrementing mm sequence counter (mm_lock_seq). - write downgrade - if the mmap_lock is downgraded to the read lock, all vma write locks are released as well (effectivelly same as write unlock). Link: https://lkml.kernel.org/r/20230227173632.3292573-13-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm.h | 82 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/mm_types.h | 8 +++++ include/linux/mmap_lock.h | 13 ++++++++ kernel/fork.c | 4 +++ mm/init-mm.c | 3 ++ 5 files changed, 110 insertions(+) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 55d02356146c..53bfb42663ea 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -624,6 +624,87 @@ struct vm_operations_struct { unsigned long addr); }; +#ifdef CONFIG_PER_VMA_LOCK +static inline void vma_init_lock(struct vm_area_struct *vma) +{ + init_rwsem(&vma->lock); + vma->vm_lock_seq = -1; +} + +/* + * Try to read-lock a vma. The function is allowed to occasionally yield false + * locked result to avoid performance overhead, in which case we fall back to + * using mmap_lock. The function should never yield false unlocked result. + */ +static inline bool vma_start_read(struct vm_area_struct *vma) +{ + /* Check before locking. A race might cause false locked result. */ + if (vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq)) + return false; + + if (unlikely(down_read_trylock(&vma->lock) == 0)) + return false; + + /* + * Overflow might produce false locked result. + * False unlocked result is impossible because we modify and check + * vma->vm_lock_seq under vma->lock protection and mm->mm_lock_seq + * modification invalidates all existing locks. + */ + if (unlikely(vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq))) { + up_read(&vma->lock); + return false; + } + return true; +} + +static inline void vma_end_read(struct vm_area_struct *vma) +{ + rcu_read_lock(); /* keeps vma alive till the end of up_read */ + up_read(&vma->lock); + rcu_read_unlock(); +} + +static inline void vma_start_write(struct vm_area_struct *vma) +{ + int mm_lock_seq; + + mmap_assert_write_locked(vma->vm_mm); + + /* + * current task is holding mmap_write_lock, both vma->vm_lock_seq and + * mm->mm_lock_seq can't be concurrently modified. + */ + mm_lock_seq = READ_ONCE(vma->vm_mm->mm_lock_seq); + if (vma->vm_lock_seq == mm_lock_seq) + return; + + down_write(&vma->lock); + vma->vm_lock_seq = mm_lock_seq; + up_write(&vma->lock); +} + +static inline void vma_assert_write_locked(struct vm_area_struct *vma) +{ + mmap_assert_write_locked(vma->vm_mm); + /* + * current task is holding mmap_write_lock, both vma->vm_lock_seq and + * mm->mm_lock_seq can't be concurrently modified. + */ + VM_BUG_ON_VMA(vma->vm_lock_seq != READ_ONCE(vma->vm_mm->mm_lock_seq), vma); +} + +#else /* CONFIG_PER_VMA_LOCK */ + +static inline void vma_init_lock(struct vm_area_struct *vma) {} +static inline bool vma_start_read(struct vm_area_struct *vma) + { return false; } +static inline void vma_end_read(struct vm_area_struct *vma) {} +static inline void vma_start_write(struct vm_area_struct *vma) {} +static inline void vma_assert_write_locked(struct vm_area_struct *vma) {} + +#endif /* CONFIG_PER_VMA_LOCK */ + static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) { static const struct vm_operations_struct dummy_vm_ops = {}; @@ -632,6 +713,7 @@ static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) vma->vm_mm = mm; vma->vm_ops = &dummy_vm_ops; INIT_LIST_HEAD(&vma->anon_vma_chain); + vma_init_lock(vma); } /* Use when VMA is not part of the VMA tree and needs no locking */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index f203e2562e00..843a45893991 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -503,6 +503,11 @@ struct vm_area_struct { vm_flags_t __private __vm_flags; }; +#ifdef CONFIG_PER_VMA_LOCK + int vm_lock_seq; + struct rw_semaphore lock; +#endif + /* * For areas with an address space and backing store, * linkage into the address_space->i_mmap interval tree. @@ -639,6 +644,9 @@ struct mm_struct { * init_mm.mmlist, and are protected * by mmlist_lock */ +#ifdef CONFIG_PER_VMA_LOCK + int mm_lock_seq; +#endif unsigned long hiwater_rss; /* High-watermark of RSS usage */ diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h index e49ba91bb1f0..aab8f1b28d26 100644 --- a/include/linux/mmap_lock.h +++ b/include/linux/mmap_lock.h @@ -72,6 +72,17 @@ static inline void mmap_assert_write_locked(struct mm_struct *mm) VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); } +#ifdef CONFIG_PER_VMA_LOCK +static inline void vma_end_write_all(struct mm_struct *mm) +{ + mmap_assert_write_locked(mm); + /* No races during update due to exclusive mmap_lock being held */ + WRITE_ONCE(mm->mm_lock_seq, mm->mm_lock_seq + 1); +} +#else +static inline void vma_end_write_all(struct mm_struct *mm) {} +#endif + static inline void mmap_init_lock(struct mm_struct *mm) { init_rwsem(&mm->mmap_lock); @@ -114,12 +125,14 @@ static inline bool mmap_write_trylock(struct mm_struct *mm) static inline void mmap_write_unlock(struct mm_struct *mm) { __mmap_lock_trace_released(mm, true); + vma_end_write_all(mm); up_write(&mm->mmap_lock); } static inline void mmap_write_downgrade(struct mm_struct *mm) { __mmap_lock_trace_acquire_returned(mm, false, true); + vma_end_write_all(mm); downgrade_write(&mm->mmap_lock); } diff --git a/kernel/fork.c b/kernel/fork.c index 93ec6e14bb65..0907776d8ed4 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -474,6 +474,7 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) */ data_race(memcpy(new, orig, sizeof(*new))); INIT_LIST_HEAD(&new->anon_vma_chain); + vma_init_lock(new); dup_anon_vma_name(orig, new); } return new; @@ -1208,6 +1209,9 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, seqcount_init(&mm->write_protect_seq); mmap_init_lock(mm); INIT_LIST_HEAD(&mm->mmlist); +#ifdef CONFIG_PER_VMA_LOCK + mm->mm_lock_seq = 0; +#endif mm_pgtables_bytes_init(mm); mm->map_count = 0; mm->locked_vm = 0; diff --git a/mm/init-mm.c b/mm/init-mm.c index c9327abb771c..33269314e060 100644 --- a/mm/init-mm.c +++ b/mm/init-mm.c @@ -37,6 +37,9 @@ struct mm_struct init_mm = { .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock), .arg_lock = __SPIN_LOCK_UNLOCKED(init_mm.arg_lock), .mmlist = LIST_HEAD_INIT(init_mm.mmlist), +#ifdef CONFIG_PER_VMA_LOCK + .mm_lock_seq = 0, +#endif .user_ns = &init_user_ns, .cpu_bitmap = CPU_BITS_NONE, #ifdef CONFIG_IOMMU_SVA -- cgit v1.2.3 From c732293331a22187d59cd485879276a1da398387 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:12 -0800 Subject: mm: mark VMA as being written when changing vm_flags Updates to vm_flags have to be done with VMA marked as being written for preventing concurrent page faults or other modifications. Link: https://lkml.kernel.org/r/20230227173632.3292573-14-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 53bfb42663ea..d0a6c99aba09 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -727,28 +727,28 @@ static inline void vm_flags_init(struct vm_area_struct *vma, static inline void vm_flags_reset(struct vm_area_struct *vma, vm_flags_t flags) { - mmap_assert_write_locked(vma->vm_mm); + vma_start_write(vma); vm_flags_init(vma, flags); } static inline void vm_flags_reset_once(struct vm_area_struct *vma, vm_flags_t flags) { - mmap_assert_write_locked(vma->vm_mm); + vma_start_write(vma); WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags); } static inline void vm_flags_set(struct vm_area_struct *vma, vm_flags_t flags) { - mmap_assert_write_locked(vma->vm_mm); + vma_start_write(vma); ACCESS_PRIVATE(vma, __vm_flags) |= flags; } static inline void vm_flags_clear(struct vm_area_struct *vma, vm_flags_t flags) { - mmap_assert_write_locked(vma->vm_mm); + vma_start_write(vma); ACCESS_PRIVATE(vma, __vm_flags) &= ~flags; } @@ -769,7 +769,7 @@ static inline void __vm_flags_mod(struct vm_area_struct *vma, static inline void vm_flags_mod(struct vm_area_struct *vma, vm_flags_t set, vm_flags_t clear) { - mmap_assert_write_locked(vma->vm_mm); + vma_start_write(vma); __vm_flags_mod(vma, set, clear); } -- cgit v1.2.3 From 55fd6fccad3172c0feaaa817f0a1283629ff183e Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:14 -0800 Subject: mm/khugepaged: write-lock VMA while collapsing a huge page Protect VMA from concurrent page fault handler while collapsing a huge page. Page fault handler needs a stable PMD to use PTL and relies on per-VMA lock to prevent concurrent PMD changes. pmdp_collapse_flush(), set_huge_pmd() and collapse_and_free_pmd() can modify a PMD, which will not be detected by a page fault handler without proper locking. Before this patch, page tables can be walked under any one of the mmap_lock, the mapping lock, and the anon_vma lock; so when khugepaged unlinks and frees page tables, it must ensure that all of those either are locked or don't exist. This patch adds a fourth lock under which page tables can be traversed, and so khugepaged must also lock out that one. [surenb@google.com: vm_lock/i_mmap_rwsem inversion in retract_page_tables] Link: https://lkml.kernel.org/r/20230303213250.3555716-1-surenb@google.com [surenb@google.com: build fix] Link: https://lkml.kernel.org/r/CAJuCfpFjWhtzRE1X=J+_JjgJzNKhq-=JT8yTBSTHthwp0pqWZw@mail.gmail.com Link: https://lkml.kernel.org/r/20230227173632.3292573-16-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm.h | 41 ++++++++++++++++++++++++++++++----------- mm/khugepaged.c | 8 ++++++++ mm/rmap.c | 31 ++++++++++++++++--------------- 3 files changed, 54 insertions(+), 26 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index d0a6c99aba09..d6a2abc51e3d 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -665,18 +665,23 @@ static inline void vma_end_read(struct vm_area_struct *vma) rcu_read_unlock(); } -static inline void vma_start_write(struct vm_area_struct *vma) +static bool __is_vma_write_locked(struct vm_area_struct *vma, int *mm_lock_seq) { - int mm_lock_seq; - mmap_assert_write_locked(vma->vm_mm); /* * current task is holding mmap_write_lock, both vma->vm_lock_seq and * mm->mm_lock_seq can't be concurrently modified. */ - mm_lock_seq = READ_ONCE(vma->vm_mm->mm_lock_seq); - if (vma->vm_lock_seq == mm_lock_seq) + *mm_lock_seq = READ_ONCE(vma->vm_mm->mm_lock_seq); + return (vma->vm_lock_seq == *mm_lock_seq); +} + +static inline void vma_start_write(struct vm_area_struct *vma) +{ + int mm_lock_seq; + + if (__is_vma_write_locked(vma, &mm_lock_seq)) return; down_write(&vma->lock); @@ -684,14 +689,26 @@ static inline void vma_start_write(struct vm_area_struct *vma) up_write(&vma->lock); } +static inline bool vma_try_start_write(struct vm_area_struct *vma) +{ + int mm_lock_seq; + + if (__is_vma_write_locked(vma, &mm_lock_seq)) + return true; + + if (!down_write_trylock(&vma->vm_lock->lock)) + return false; + + vma->vm_lock_seq = mm_lock_seq; + up_write(&vma->vm_lock->lock); + return true; +} + static inline void vma_assert_write_locked(struct vm_area_struct *vma) { - mmap_assert_write_locked(vma->vm_mm); - /* - * current task is holding mmap_write_lock, both vma->vm_lock_seq and - * mm->mm_lock_seq can't be concurrently modified. - */ - VM_BUG_ON_VMA(vma->vm_lock_seq != READ_ONCE(vma->vm_mm->mm_lock_seq), vma); + int mm_lock_seq; + + VM_BUG_ON_VMA(!__is_vma_write_locked(vma, &mm_lock_seq), vma); } #else /* CONFIG_PER_VMA_LOCK */ @@ -701,6 +718,8 @@ static inline bool vma_start_read(struct vm_area_struct *vma) { return false; } static inline void vma_end_read(struct vm_area_struct *vma) {} static inline void vma_start_write(struct vm_area_struct *vma) {} +static inline bool vma_try_start_write(struct vm_area_struct *vma) + { return true; } static inline void vma_assert_write_locked(struct vm_area_struct *vma) {} #endif /* CONFIG_PER_VMA_LOCK */ diff --git a/mm/khugepaged.c b/mm/khugepaged.c index c7317678cb10..bee7fd7db380 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1056,6 +1056,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, if (result != SCAN_SUCCEED) goto out_up_write; + vma_start_write(vma); anon_vma_lock_write(vma->anon_vma); mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, address, @@ -1517,6 +1518,9 @@ int collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr, goto drop_hpage; } + /* Lock the vma before taking i_mmap and page table locks */ + vma_start_write(vma); + /* * We need to lock the mapping so that from here on, only GUP-fast and * hardware page walks can access the parts of the page tables that @@ -1694,6 +1698,10 @@ static int retract_page_tables(struct address_space *mapping, pgoff_t pgoff, result = SCAN_PTE_MAPPED_HUGEPAGE; if ((cc->is_khugepaged || is_target) && mmap_write_trylock(mm)) { + /* trylock for the same lock inversion as above */ + if (!vma_try_start_write(vma)) + goto unlock_next; + /* * Re-check whether we have an ->anon_vma, because * collapse_and_free_pmd() requires that either no diff --git a/mm/rmap.c b/mm/rmap.c index 1ea2756b2797..ba901c416785 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -25,21 +25,22 @@ * mapping->invalidate_lock (in filemap_fault) * page->flags PG_locked (lock_page) * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share, see hugetlbfs below) - * mapping->i_mmap_rwsem - * anon_vma->rwsem - * mm->page_table_lock or pte_lock - * swap_lock (in swap_duplicate, swap_info_get) - * mmlist_lock (in mmput, drain_mmlist and others) - * mapping->private_lock (in block_dirty_folio) - * folio_lock_memcg move_lock (in block_dirty_folio) - * i_pages lock (widely used) - * lruvec->lru_lock (in folio_lruvec_lock_irq) - * inode->i_lock (in set_page_dirty's __mark_inode_dirty) - * bdi.wb->list_lock (in set_page_dirty's __mark_inode_dirty) - * sb_lock (within inode_lock in fs/fs-writeback.c) - * i_pages lock (widely used, in set_page_dirty, - * in arch-dependent flush_dcache_mmap_lock, - * within bdi.wb->list_lock in __sync_single_inode) + * vma_start_write + * mapping->i_mmap_rwsem + * anon_vma->rwsem + * mm->page_table_lock or pte_lock + * swap_lock (in swap_duplicate, swap_info_get) + * mmlist_lock (in mmput, drain_mmlist and others) + * mapping->private_lock (in block_dirty_folio) + * folio_lock_memcg move_lock (in block_dirty_folio) + * i_pages lock (widely used) + * lruvec->lru_lock (in folio_lruvec_lock_irq) + * inode->i_lock (in set_page_dirty's __mark_inode_dirty) + * bdi.wb->list_lock (in set_page_dirty's __mark_inode_dirty) + * sb_lock (within inode_lock in fs/fs-writeback.c) + * i_pages lock (widely used, in set_page_dirty, + * in arch-dependent flush_dcache_mmap_lock, + * within bdi.wb->list_lock in __sync_single_inode) * * anon_vma->rwsem,mapping->i_mmap_rwsem (memory_failure, collect_procs_anon) * ->tasklist_lock -- cgit v1.2.3 From 457f67be5910a2b5f1fda8af06bfe4d3492a0a4f Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:21 -0800 Subject: mm: introduce vma detached flag Per-vma locking mechanism will search for VMA under RCU protection and then after locking it, has to ensure it was not removed from the VMA tree after we found it. To make this check efficient, introduce a vma->detached flag to mark VMAs which were removed from the VMA tree. Link: https://lkml.kernel.org/r/20230227173632.3292573-23-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm.h | 11 +++++++++++ include/linux/mm_types.h | 3 +++ mm/mmap.c | 2 ++ 3 files changed, 16 insertions(+) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index d6a2abc51e3d..d0f289bfef01 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -711,6 +711,14 @@ static inline void vma_assert_write_locked(struct vm_area_struct *vma) VM_BUG_ON_VMA(!__is_vma_write_locked(vma, &mm_lock_seq), vma); } +static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached) +{ + /* When detaching vma should be write-locked */ + if (detached) + vma_assert_write_locked(vma); + vma->detached = detached; +} + #else /* CONFIG_PER_VMA_LOCK */ static inline void vma_init_lock(struct vm_area_struct *vma) {} @@ -721,6 +729,8 @@ static inline void vma_start_write(struct vm_area_struct *vma) {} static inline bool vma_try_start_write(struct vm_area_struct *vma) { return true; } static inline void vma_assert_write_locked(struct vm_area_struct *vma) {} +static inline void vma_mark_detached(struct vm_area_struct *vma, + bool detached) {} #endif /* CONFIG_PER_VMA_LOCK */ @@ -732,6 +742,7 @@ static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) vma->vm_mm = mm; vma->vm_ops = &dummy_vm_ops; INIT_LIST_HEAD(&vma->anon_vma_chain); + vma_mark_detached(vma, false); vma_init_lock(vma); } diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 843a45893991..3248ae45cb2e 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -506,6 +506,9 @@ struct vm_area_struct { #ifdef CONFIG_PER_VMA_LOCK int vm_lock_seq; struct rw_semaphore lock; + + /* Flag to indicate areas detached from the mm->mm_mt tree */ + bool detached; #endif /* diff --git a/mm/mmap.c b/mm/mmap.c index 18aed0ea6bd3..b42f58591b9a 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -599,6 +599,7 @@ static inline void vma_complete(struct vma_prepare *vp, if (vp->remove) { again: + vma_mark_detached(vp->remove, true); if (vp->file) { uprobe_munmap(vp->remove, vp->remove->vm_start, vp->remove->vm_end); @@ -2276,6 +2277,7 @@ static inline int munmap_sidetree(struct vm_area_struct *vma, if (mas_store_gfp(mas_detach, vma, GFP_KERNEL)) return -ENOMEM; + vma_mark_detached(vma, true); if (vma->vm_flags & VM_LOCKED) vma->vm_mm->locked_vm -= vma_pages(vma); -- cgit v1.2.3 From 50ee32537206140e4cf6e47024be29a84d458d49 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:22 -0800 Subject: mm: introduce lock_vma_under_rcu to be used from arch-specific code Introduce lock_vma_under_rcu function to lookup and lock a VMA during page fault handling. When VMA is not found, can't be locked or changes after being locked, the function returns NULL. The lookup is performed under RCU protection to prevent the found VMA from being destroyed before the VMA lock is acquired. VMA lock statistics are updated according to the results. For now only anonymous VMAs can be searched this way. In other cases the function returns NULL. Link: https://lkml.kernel.org/r/20230227173632.3292573-24-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm.h | 3 +++ mm/memory.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 49 insertions(+) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index d0f289bfef01..0619f9fa7581 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -719,6 +719,9 @@ static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached) vma->detached = detached; } +struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, + unsigned long address); + #else /* CONFIG_PER_VMA_LOCK */ static inline void vma_init_lock(struct vm_area_struct *vma) {} diff --git a/mm/memory.c b/mm/memory.c index 8ca78ae8bba7..1235de20af73 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5232,6 +5232,52 @@ vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address, } EXPORT_SYMBOL_GPL(handle_mm_fault); +#ifdef CONFIG_PER_VMA_LOCK +/* + * Lookup and lock a VMA under RCU protection. Returned VMA is guaranteed to be + * stable and not isolated. If the VMA is not found or is being modified the + * function returns NULL. + */ +struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, + unsigned long address) +{ + MA_STATE(mas, &mm->mm_mt, address, address); + struct vm_area_struct *vma; + + rcu_read_lock(); +retry: + vma = mas_walk(&mas); + if (!vma) + goto inval; + + /* Only anonymous vmas are supported for now */ + if (!vma_is_anonymous(vma)) + goto inval; + + if (!vma_start_read(vma)) + goto inval; + + /* Check since vm_start/vm_end might change before we lock the VMA */ + if (unlikely(address < vma->vm_start || address >= vma->vm_end)) { + vma_end_read(vma); + goto inval; + } + + /* Check if the VMA got isolated after we found it */ + if (vma->detached) { + vma_end_read(vma); + /* The area was replaced with another one */ + goto retry; + } + + rcu_read_unlock(); + return vma; +inval: + rcu_read_unlock(); + return NULL; +} +#endif /* CONFIG_PER_VMA_LOCK */ + #ifndef __PAGETABLE_P4D_FOLDED /* * Allocate p4d page table. -- cgit v1.2.3 From 55324e46eb8b886ecd08c9a089d3a694c705b3b0 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:24 -0800 Subject: mm: add FAULT_FLAG_VMA_LOCK flag Add a new flag to distinguish page faults handled under protection of per-vma lock. [surenb@google.com: document FAULT_FLAG_VMA_LOCK flag] Link: https://lkml.kernel.org/r/20230301022720.1380780-2-surenb@google.com Link: https://lore.kernel.org/all/20230301113648.7c279865@canb.auug.org.au/ Link: https://lkml.kernel.org/r/20230227173632.3292573-26-surenb@google.com Signed-off-by: Suren Baghdasaryan Reviewed-by: Laurent Dufour Cc: Dan Carpenter Cc: David Hildenbrand Cc: David Howells Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: Liam R. Howlett Cc: Mathieu Desnoyers Cc: Matthew Wilcox Cc: Pavel Tatashin Cc: Yu Zhao Signed-off-by: Andrew Morton --- include/linux/mm.h | 3 ++- include/linux/mm_types.h | 2 ++ 2 files changed, 4 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 0619f9fa7581..1876825d6700 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -479,7 +479,8 @@ static inline bool fault_flag_allow_retry_first(enum fault_flag flags) { FAULT_FLAG_USER, "USER" }, \ { FAULT_FLAG_REMOTE, "REMOTE" }, \ { FAULT_FLAG_INSTRUCTION, "INSTRUCTION" }, \ - { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" } + { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" }, \ + { FAULT_FLAG_VMA_LOCK, "VMA_LOCK" } /* * vm_fault is filled by the pagefault handler and passed to the vma's diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 3248ae45cb2e..3a6cf4c2edd0 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -1049,6 +1049,7 @@ typedef struct { * mapped after the fault. * @FAULT_FLAG_ORIG_PTE_VALID: whether the fault has vmf->orig_pte cached. * We should only access orig_pte if this flag set. + * @FAULT_FLAG_VMA_LOCK: The fault is handled under VMA lock. * * About @FAULT_FLAG_ALLOW_RETRY and @FAULT_FLAG_TRIED: we can specify * whether we would allow page faults to retry by specifying these two @@ -1086,6 +1087,7 @@ enum fault_flag { FAULT_FLAG_INTERRUPTIBLE = 1 << 9, FAULT_FLAG_UNSHARE = 1 << 10, FAULT_FLAG_ORIG_PTE_VALID = 1 << 11, + FAULT_FLAG_VMA_LOCK = 1 << 12, }; typedef unsigned int __bitwise zap_flags_t; -- cgit v1.2.3 From 52f238653e452e0fda61e880f263a173d219acd1 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:27 -0800 Subject: mm: introduce per-VMA lock statistics Add a new CONFIG_PER_VMA_LOCK_STATS config option to dump extra statistics about handling page fault under VMA lock. Link: https://lkml.kernel.org/r/20230227173632.3292573-29-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/vm_event_item.h | 6 ++++++ include/linux/vmstat.h | 6 ++++++ mm/Kconfig.debug | 6 ++++++ mm/memory.c | 2 ++ mm/vmstat.c | 6 ++++++ 5 files changed, 26 insertions(+) (limited to 'include') diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h index 7f5d1caf5890..8abfa1240040 100644 --- a/include/linux/vm_event_item.h +++ b/include/linux/vm_event_item.h @@ -149,6 +149,12 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, #ifdef CONFIG_X86 DIRECT_MAP_LEVEL2_SPLIT, DIRECT_MAP_LEVEL3_SPLIT, +#endif +#ifdef CONFIG_PER_VMA_LOCK_STATS + VMA_LOCK_SUCCESS, + VMA_LOCK_ABORT, + VMA_LOCK_RETRY, + VMA_LOCK_MISS, #endif NR_VM_EVENT_ITEMS }; diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h index 19cf5b6892ce..fed855bae6d8 100644 --- a/include/linux/vmstat.h +++ b/include/linux/vmstat.h @@ -125,6 +125,12 @@ static inline void vm_events_fold_cpu(int cpu) #define count_vm_tlb_events(x, y) do { (void)(y); } while (0) #endif +#ifdef CONFIG_PER_VMA_LOCK_STATS +#define count_vm_vma_lock_event(x) count_vm_event(x) +#else +#define count_vm_vma_lock_event(x) do {} while (0) +#endif + #define __count_zid_vm_events(item, zid, delta) \ __count_vm_events(item##_NORMAL - ZONE_NORMAL + zid, delta) diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug index c3547a373c9c..4965a7333a3f 100644 --- a/mm/Kconfig.debug +++ b/mm/Kconfig.debug @@ -279,3 +279,9 @@ config DEBUG_KMEMLEAK_AUTO_SCAN If unsure, say Y. +config PER_VMA_LOCK_STATS + bool "Statistics for per-vma locks" + depends on PER_VMA_LOCK + default y + help + Statistics for per-vma locks. diff --git a/mm/memory.c b/mm/memory.c index 55ac9cdfd398..9999574a9636 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5284,6 +5284,7 @@ retry: /* Check if the VMA got isolated after we found it */ if (vma->detached) { vma_end_read(vma); + count_vm_vma_lock_event(VMA_LOCK_MISS); /* The area was replaced with another one */ goto retry; } @@ -5292,6 +5293,7 @@ retry: return vma; inval: rcu_read_unlock(); + count_vm_vma_lock_event(VMA_LOCK_ABORT); return NULL; } #endif /* CONFIG_PER_VMA_LOCK */ diff --git a/mm/vmstat.c b/mm/vmstat.c index b7307627772d..c28046371b45 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1399,6 +1399,12 @@ const char * const vmstat_text[] = { "direct_map_level2_splits", "direct_map_level3_splits", #endif +#ifdef CONFIG_PER_VMA_LOCK_STATS + "vma_lock_success", + "vma_lock_abort", + "vma_lock_retry", + "vma_lock_miss", +#endif #endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */ }; #endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA || CONFIG_MEMCG */ -- cgit v1.2.3 From 0d2ebf9c3f7822e7ba3e4792ea3b6b19aa2da34a Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:31 -0800 Subject: mm/mmap: free vm_area_struct without call_rcu in exit_mmap call_rcu() can take a long time when callback offloading is enabled. Its use in the vm_area_free can cause regressions in the exit path when multiple VMAs are being freed. Because exit_mmap() is called only after the last mm user drops its refcount, the page fault handlers can't be racing with it. Any other possible user like oom-reaper or process_mrelease are already synchronized using mmap_lock. Therefore exit_mmap() can free VMAs directly, without the use of call_rcu(). Expose __vm_area_free() and use it from exit_mmap() to avoid possible call_rcu() floods and performance regressions caused by it. Link: https://lkml.kernel.org/r/20230227173632.3292573-33-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm.h | 2 ++ kernel/fork.c | 2 +- mm/mmap.c | 11 +++++++---- 3 files changed, 10 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 1876825d6700..f31c75dc190e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -257,6 +257,8 @@ void setup_initial_init_mm(void *start_code, void *end_code, struct vm_area_struct *vm_area_alloc(struct mm_struct *); struct vm_area_struct *vm_area_dup(struct vm_area_struct *); void vm_area_free(struct vm_area_struct *); +/* Use only if VMA has no other users */ +void __vm_area_free(struct vm_area_struct *vma); #ifndef CONFIG_MMU extern struct rb_root nommu_region_tree; diff --git a/kernel/fork.c b/kernel/fork.c index 76fcc08984d4..f86f7e917954 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -480,7 +480,7 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) return new; } -static void __vm_area_free(struct vm_area_struct *vma) +void __vm_area_free(struct vm_area_struct *vma) { free_anon_vma_name(vma); kmem_cache_free(vm_area_cachep, vma); diff --git a/mm/mmap.c b/mm/mmap.c index b42f58591b9a..511f656eb423 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -133,7 +133,7 @@ void unlink_file_vma(struct vm_area_struct *vma) /* * Close a vm structure and free it. */ -static void remove_vma(struct vm_area_struct *vma) +static void remove_vma(struct vm_area_struct *vma, bool unreachable) { might_sleep(); if (vma->vm_ops && vma->vm_ops->close) @@ -141,7 +141,10 @@ static void remove_vma(struct vm_area_struct *vma) if (vma->vm_file) fput(vma->vm_file); mpol_put(vma_policy(vma)); - vm_area_free(vma); + if (unreachable) + __vm_area_free(vma); + else + vm_area_free(vma); } static inline struct vm_area_struct *vma_prev_limit(struct vma_iterator *vmi, @@ -2145,7 +2148,7 @@ static inline void remove_mt(struct mm_struct *mm, struct ma_state *mas) if (vma->vm_flags & VM_ACCOUNT) nr_accounted += nrpages; vm_stat_account(mm, vma->vm_flags, -nrpages); - remove_vma(vma); + remove_vma(vma, false); } vm_unacct_memory(nr_accounted); validate_mm(mm); @@ -3078,7 +3081,7 @@ void exit_mmap(struct mm_struct *mm) do { if (vma->vm_flags & VM_ACCOUNT) nr_accounted += vma_pages(vma); - remove_vma(vma); + remove_vma(vma, true); count++; cond_resched(); } while ((vma = mas_find(&mas, ULONG_MAX)) != NULL); -- cgit v1.2.3 From c7f8f31c00d187a2c71a241c7f2bd6aa102a4e6f Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 27 Feb 2023 09:36:32 -0800 Subject: mm: separate vma->lock from vm_area_struct vma->lock being part of the vm_area_struct causes performance regression during page faults because during contention its count and owner fields are constantly updated and having other parts of vm_area_struct used during page fault handling next to them causes constant cache line bouncing. Fix that by moving the lock outside of the vm_area_struct. All attempts to keep vma->lock inside vm_area_struct in a separate cache line still produce performance regression especially on NUMA machines. Smallest regression was achieved when lock is placed in the fourth cache line but that bloats vm_area_struct to 256 bytes. Considering performance and memory impact, separate lock looks like the best option. It increases memory footprint of each VMA but that can be optimized later if the new size causes issues. Note that after this change vma_init() does not allocate or initialize vma->lock anymore. A number of drivers allocate a pseudo VMA on the stack but they never use the VMA's lock, therefore it does not need to be allocated. The future drivers which might need the VMA lock should use vm_area_alloc()/vm_area_free() to allocate the VMA. Link: https://lkml.kernel.org/r/20230227173632.3292573-34-surenb@google.com Signed-off-by: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mm.h | 23 +++++++-------- include/linux/mm_types.h | 6 +++- kernel/fork.c | 73 ++++++++++++++++++++++++++++++++++++++---------- 3 files changed, 74 insertions(+), 28 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index f31c75dc190e..f5487a86b154 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -628,12 +628,6 @@ struct vm_operations_struct { }; #ifdef CONFIG_PER_VMA_LOCK -static inline void vma_init_lock(struct vm_area_struct *vma) -{ - init_rwsem(&vma->lock); - vma->vm_lock_seq = -1; -} - /* * Try to read-lock a vma. The function is allowed to occasionally yield false * locked result to avoid performance overhead, in which case we fall back to @@ -645,17 +639,17 @@ static inline bool vma_start_read(struct vm_area_struct *vma) if (vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq)) return false; - if (unlikely(down_read_trylock(&vma->lock) == 0)) + if (unlikely(down_read_trylock(&vma->vm_lock->lock) == 0)) return false; /* * Overflow might produce false locked result. * False unlocked result is impossible because we modify and check - * vma->vm_lock_seq under vma->lock protection and mm->mm_lock_seq + * vma->vm_lock_seq under vma->vm_lock protection and mm->mm_lock_seq * modification invalidates all existing locks. */ if (unlikely(vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq))) { - up_read(&vma->lock); + up_read(&vma->vm_lock->lock); return false; } return true; @@ -664,7 +658,7 @@ static inline bool vma_start_read(struct vm_area_struct *vma) static inline void vma_end_read(struct vm_area_struct *vma) { rcu_read_lock(); /* keeps vma alive till the end of up_read */ - up_read(&vma->lock); + up_read(&vma->vm_lock->lock); rcu_read_unlock(); } @@ -687,9 +681,9 @@ static inline void vma_start_write(struct vm_area_struct *vma) if (__is_vma_write_locked(vma, &mm_lock_seq)) return; - down_write(&vma->lock); + down_write(&vma->vm_lock->lock); vma->vm_lock_seq = mm_lock_seq; - up_write(&vma->lock); + up_write(&vma->vm_lock->lock); } static inline bool vma_try_start_write(struct vm_area_struct *vma) @@ -740,6 +734,10 @@ static inline void vma_mark_detached(struct vm_area_struct *vma, #endif /* CONFIG_PER_VMA_LOCK */ +/* + * WARNING: vma_init does not initialize vma->vm_lock. + * Use vm_area_alloc()/vm_area_free() if vma needs locking. + */ static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) { static const struct vm_operations_struct dummy_vm_ops = {}; @@ -749,7 +747,6 @@ static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) vma->vm_ops = &dummy_vm_ops; INIT_LIST_HEAD(&vma->anon_vma_chain); vma_mark_detached(vma, false); - vma_init_lock(vma); } /* Use when VMA is not part of the VMA tree and needs no locking */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 3a6cf4c2edd0..1b3031e95215 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -471,6 +471,10 @@ struct anon_vma_name { char name[]; }; +struct vma_lock { + struct rw_semaphore lock; +}; + /* * This struct describes a virtual memory area. There is one of these * per VM-area/task. A VM area is any part of the process virtual memory @@ -505,7 +509,7 @@ struct vm_area_struct { #ifdef CONFIG_PER_VMA_LOCK int vm_lock_seq; - struct rw_semaphore lock; + struct vma_lock *vm_lock; /* Flag to indicate areas detached from the mm->mm_mt tree */ bool detached; diff --git a/kernel/fork.c b/kernel/fork.c index f86f7e917954..c75088367bb4 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -451,13 +451,49 @@ static struct kmem_cache *vm_area_cachep; /* SLAB cache for mm_struct structures (tsk->mm) */ static struct kmem_cache *mm_cachep; +#ifdef CONFIG_PER_VMA_LOCK + +/* SLAB cache for vm_area_struct.lock */ +static struct kmem_cache *vma_lock_cachep; + +static bool vma_lock_alloc(struct vm_area_struct *vma) +{ + vma->vm_lock = kmem_cache_alloc(vma_lock_cachep, GFP_KERNEL); + if (!vma->vm_lock) + return false; + + init_rwsem(&vma->vm_lock->lock); + vma->vm_lock_seq = -1; + + return true; +} + +static inline void vma_lock_free(struct vm_area_struct *vma) +{ + kmem_cache_free(vma_lock_cachep, vma->vm_lock); +} + +#else /* CONFIG_PER_VMA_LOCK */ + +static inline bool vma_lock_alloc(struct vm_area_struct *vma) { return true; } +static inline void vma_lock_free(struct vm_area_struct *vma) {} + +#endif /* CONFIG_PER_VMA_LOCK */ + struct vm_area_struct *vm_area_alloc(struct mm_struct *mm) { struct vm_area_struct *vma; vma = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL); - if (vma) - vma_init(vma, mm); + if (!vma) + return NULL; + + vma_init(vma, mm); + if (!vma_lock_alloc(vma)) { + kmem_cache_free(vm_area_cachep, vma); + return NULL; + } + return vma; } @@ -465,24 +501,30 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) { struct vm_area_struct *new = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL); - if (new) { - ASSERT_EXCLUSIVE_WRITER(orig->vm_flags); - ASSERT_EXCLUSIVE_WRITER(orig->vm_file); - /* - * orig->shared.rb may be modified concurrently, but the clone - * will be reinitialized. - */ - data_race(memcpy(new, orig, sizeof(*new))); - INIT_LIST_HEAD(&new->anon_vma_chain); - vma_init_lock(new); - dup_anon_vma_name(orig, new); + if (!new) + return NULL; + + ASSERT_EXCLUSIVE_WRITER(orig->vm_flags); + ASSERT_EXCLUSIVE_WRITER(orig->vm_file); + /* + * orig->shared.rb may be modified concurrently, but the clone + * will be reinitialized. + */ + data_race(memcpy(new, orig, sizeof(*new))); + if (!vma_lock_alloc(new)) { + kmem_cache_free(vm_area_cachep, new); + return NULL; } + INIT_LIST_HEAD(&new->anon_vma_chain); + dup_anon_vma_name(orig, new); + return new; } void __vm_area_free(struct vm_area_struct *vma) { free_anon_vma_name(vma); + vma_lock_free(vma); kmem_cache_free(vm_area_cachep, vma); } @@ -493,7 +535,7 @@ static void vm_area_free_rcu_cb(struct rcu_head *head) vm_rcu); /* The vma should not be locked while being destroyed. */ - VM_BUG_ON_VMA(rwsem_is_locked(&vma->lock), vma); + VM_BUG_ON_VMA(rwsem_is_locked(&vma->vm_lock->lock), vma); __vm_area_free(vma); } #endif @@ -3152,6 +3194,9 @@ void __init proc_caches_init(void) NULL); vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT); +#ifdef CONFIG_PER_VMA_LOCK + vma_lock_cachep = KMEM_CACHE(vma_lock, SLAB_PANIC|SLAB_ACCOUNT); +#endif mmap_init(); nsproxy_cache_init(); } -- cgit v1.2.3 From ef6a22b70f6d90449a5c797b8968a682824e2011 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Wed, 1 Mar 2023 17:49:00 +0530 Subject: sched/numa: apply the scan delay to every new vma Pach series "sched/numa: Enhance vma scanning", v3. The patchset proposes one of the enhancements to numa vma scanning suggested by Mel. This is continuation of [3]. Reposting the rebased patchset to akpm mm-unstable tree (March 1) Existing mechanism of scan period involves, scan period derived from per-thread stats. Process Adaptive autoNUMA [1] proposed to gather NUMA fault stats at per-process level to capture aplication behaviour better. During that course of discussion, Mel proposed several ideas to enhance current numa balancing. One of the suggestion was below Track what threads access a VMA. The suggestion was to use an unsigned long pid_mask and use the lower bits to tag approximately what threads access a VMA. Skip VMAs that did not trap a fault. This would be approximate because of PID collisions but would reduce scanning of areas the thread is not interested in. The above suggestion intends not to penalize threads that has no interest in the vma, thus reduce scanning overhead. V3 changes are mostly based on PeterZ comments (details below in changes) Summary of patchset: Current patchset implements: 1. Delay the vma scanning logic for newly created VMA's so that additional overhead of scanning is not incurred for short lived tasks (implementation by Mel) 2. Store the information of tasks accessing VMA in 2 windows. It is regularly cleared in (4*sysctl_numa_balancing_scan_delay) interval. The above time is derived from experimenting (Suggested by PeterZ) to balance between frequent clearing vs obsolete access data 3. hash_32 used to encode task index accessing VMA information 4. VMA's acess information is used to skip scanning for the tasks which had not accessed VMA Changes since V2: patch1: - Renaming of structure, macro to function, - Add explanation to heuristics - Adding more details from result (PeterZ) Patch2: - Usage of test and set bit (PeterZ) - Move storing access PID info to numa_migrate_prep() - Add a note on fainess among tasks allowed to scan (PeterZ) Patch3: - Maintain two windows of access PID information (PeterZ supported implementation and Gave idea to extend to N if needed) Patch4: - Apply hash_32 function to track VMA accessing PIDs (PeterZ) Changes since RFC V1: - Include Mel's vma scan delay patch - Change the accessing pid store logic (Thanks Mel) - Fencing structure / code to NUMA_BALANCING (David, Mel) - Adding clearing access PID logic (Mel) - Descriptive change log ( Mike Rapoport) Things to ponder over: ========================================== - Improvement to clearing accessing PIDs logic (discussed in-detail in patch3 itself (Done in this patchset by implementing 2 window history) - Current scan period is not changed in the patchset, so we do see frequent tries to scan. Relaxing scan period dynamically could improve results further. [1] sched/numa: Process Adaptive autoNUMA Link: https://lore.kernel.org/lkml/20220128052851.17162-1-bharata@amd.com/T/ [2] RFC V1 Link: https://lore.kernel.org/all/cover.1673610485.git.raghavendra.kt@amd.com/ [3] V2 Link: https://lore.kernel.org/lkml/cover.1675159422.git.raghavendra.kt@amd.com/ Results: Summary: Huge autonuma cost reduction seen in mmtest. Kernbench improvement is more than 5% and huge system time (80%+) improvement from mmtest autonuma. (dbench had huge std deviation to post) kernbench =========== 6.2.0-mmunstable-base 6.2.0-mmunstable-patched Amean user-256 22002.51 ( 0.00%) 22649.95 * -2.94%* Amean syst-256 10162.78 ( 0.00%) 8214.13 * 19.17%* Amean elsp-256 160.74 ( 0.00%) 156.92 * 2.38%* Duration User 66017.43 67959.84 Duration System 30503.15 24657.03 Duration Elapsed 504.61 493.12 6.2.0-mmunstable-base 6.2.0-mmunstable-patched Ops NUMA alloc hit 1738835089.00 1738780310.00 Ops NUMA alloc local 1738834448.00 1738779711.00 Ops NUMA base-page range updates 477310.00 392566.00 Ops NUMA PTE updates 477310.00 392566.00 Ops NUMA hint faults 96817.00 87555.00 Ops NUMA hint local faults % 10150.00 2192.00 Ops NUMA hint local percent 10.48 2.50 Ops NUMA pages migrated 86660.00 85363.00 Ops AutoNUMA cost 489.07 442.14 autonumabench =============== 6.2.0-mmunstable-base 6.2.0-mmunstable-patched Amean syst-NUMA01 399.50 ( 0.00%) 52.05 * 86.97%* Amean syst-NUMA01_THREADLOCAL 0.21 ( 0.00%) 0.22 * -5.41%* Amean syst-NUMA02 0.80 ( 0.00%) 0.78 * 2.68%* Amean syst-NUMA02_SMT 0.65 ( 0.00%) 0.68 * -3.95%* Amean elsp-NUMA01 313.26 ( 0.00%) 313.11 * 0.05%* Amean elsp-NUMA01_THREADLOCAL 1.06 ( 0.00%) 1.08 * -1.76%* Amean elsp-NUMA02 3.19 ( 0.00%) 3.24 * -1.52%* Amean elsp-NUMA02_SMT 3.72 ( 0.00%) 3.61 * 2.92%* Duration User 396433.47 324835.96 Duration System 2808.70 376.66 Duration Elapsed 2258.61 2258.12 6.2.0-mmunstable-base 6.2.0-mmunstable-patched Ops NUMA alloc hit 59921806.00 49623489.00 Ops NUMA alloc miss 0.00 0.00 Ops NUMA interleave hit 0.00 0.00 Ops NUMA alloc local 59920880.00 49622594.00 Ops NUMA base-page range updates 152259275.00 50075.00 Ops NUMA PTE updates 152259275.00 50075.00 Ops NUMA PMD updates 0.00 0.00 Ops NUMA hint faults 154660352.00 39014.00 Ops NUMA hint local faults % 138550501.00 23139.00 Ops NUMA hint local percent 89.58 59.31 Ops NUMA pages migrated 8179067.00 14147.00 Ops AutoNUMA cost 774522.98 195.69 This patch (of 4): Currently whenever a new task is created we wait for sysctl_numa_balancing_scan_delay to avoid unnessary scanning overhead. Extend the same logic to new or very short-lived VMAs. [raghavendra.kt@amd.com: add initialization in vm_area_dup())] Link: https://lkml.kernel.org/r/cover.1677672277.git.raghavendra.kt@amd.com Link: https://lkml.kernel.org/r/7a6fbba87c8b51e67efd3e74285bb4cb311a16ca.1677672277.git.raghavendra.kt@amd.com Signed-off-by: Mel Gorman Signed-off-by: Raghavendra K T Cc: Bharata B Rao Cc: David Hildenbrand Cc: Ingo Molnar Cc: Mike Rapoport Cc: Peter Zijlstra Cc: Disha Talreja Signed-off-by: Andrew Morton --- include/linux/mm.h | 16 ++++++++++++++++ include/linux/mm_types.h | 7 +++++++ kernel/fork.c | 2 ++ kernel/sched/fair.c | 19 +++++++++++++++++++ 4 files changed, 44 insertions(+) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index f5487a86b154..9f08a11b355c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -29,6 +29,7 @@ #include #include #include +#include struct mempolicy; struct anon_vma; @@ -627,6 +628,20 @@ struct vm_operations_struct { unsigned long addr); }; +#ifdef CONFIG_NUMA_BALANCING +static inline void vma_numab_state_init(struct vm_area_struct *vma) +{ + vma->numab_state = NULL; +} +static inline void vma_numab_state_free(struct vm_area_struct *vma) +{ + kfree(vma->numab_state); +} +#else +static inline void vma_numab_state_init(struct vm_area_struct *vma) {} +static inline void vma_numab_state_free(struct vm_area_struct *vma) {} +#endif /* CONFIG_NUMA_BALANCING */ + #ifdef CONFIG_PER_VMA_LOCK /* * Try to read-lock a vma. The function is allowed to occasionally yield false @@ -747,6 +762,7 @@ static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) vma->vm_ops = &dummy_vm_ops; INIT_LIST_HEAD(&vma->anon_vma_chain); vma_mark_detached(vma, false); + vma_numab_state_init(vma); } /* Use when VMA is not part of the VMA tree and needs no locking */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 1b3031e95215..3e1a42673769 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -475,6 +475,10 @@ struct vma_lock { struct rw_semaphore lock; }; +struct vma_numab_state { + unsigned long next_scan; +}; + /* * This struct describes a virtual memory area. There is one of these * per VM-area/task. A VM area is any part of the process virtual memory @@ -560,6 +564,9 @@ struct vm_area_struct { #endif #ifdef CONFIG_NUMA struct mempolicy *vm_policy; /* NUMA policy for the VMA */ +#endif +#ifdef CONFIG_NUMA_BALANCING + struct vma_numab_state *numab_state; /* NUMA Balancing state */ #endif struct vm_userfaultfd_ctx vm_userfaultfd_ctx; } __randomize_layout; diff --git a/kernel/fork.c b/kernel/fork.c index c75088367bb4..2bde99037652 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -516,6 +516,7 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) return NULL; } INIT_LIST_HEAD(&new->anon_vma_chain); + vma_numab_state_init(new); dup_anon_vma_name(orig, new); return new; @@ -523,6 +524,7 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) void __vm_area_free(struct vm_area_struct *vma) { + vma_numab_state_free(vma); free_anon_vma_name(vma); vma_lock_free(vma); kmem_cache_free(vm_area_cachep, vma); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6986ea31c984..7072de1686d5 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3027,6 +3027,25 @@ static void task_numa_work(struct callback_head *work) if (!vma_is_accessible(vma)) continue; + /* Initialise new per-VMA NUMAB state. */ + if (!vma->numab_state) { + vma->numab_state = kzalloc(sizeof(struct vma_numab_state), + GFP_KERNEL); + if (!vma->numab_state) + continue; + + vma->numab_state->next_scan = now + + msecs_to_jiffies(sysctl_numa_balancing_scan_delay); + } + + /* + * Scanning the VMA's of short lived tasks add more overhead. So + * delay the scan for new VMAs. + */ + if (mm->numa_scan_seq && time_before(jiffies, + vma->numab_state->next_scan)) + continue; + do { start = max(start, vma->vm_start); end = ALIGN(start + (pages << PAGE_SHIFT), HPAGE_SIZE); -- cgit v1.2.3 From fc137c0ddab29b591db6a091dc6d7ce20ccb73f2 Mon Sep 17 00:00:00 2001 From: Raghavendra K T Date: Wed, 1 Mar 2023 17:49:01 +0530 Subject: sched/numa: enhance vma scanning logic During Numa scanning make sure only relevant vmas of the tasks are scanned. Before: All the tasks of a process participate in scanning the vma even if they do not access vma in it's lifespan. Now: Except cases of first few unconditional scans, if a process do not touch vma (exluding false positive cases of PID collisions) tasks no longer scan all vma Logic used: 1) 6 bits of PID used to mark active bit in vma numab status during fault to remember PIDs accessing vma. (Thanks Mel) 2) Subsequently in scan path, vma scanning is skipped if current PID had not accessed vma. 3) First two times we do allow unconditional scan to preserve earlier behaviour of scanning. Acknowledgement to Bharata B Rao for initial patch to store pid information and Peter Zijlstra (Usage of test and set bit) Link: https://lkml.kernel.org/r/092f03105c7c1d3450f4636b1ea350407f07640e.1677672277.git.raghavendra.kt@amd.com Signed-off-by: Raghavendra K T Suggested-by: Mel Gorman Cc: David Hildenbrand Cc: Disha Talreja Cc: Ingo Molnar Cc: Mike Rapoport Signed-off-by: Andrew Morton --- include/linux/mm.h | 14 ++++++++++++++ include/linux/mm_types.h | 1 + kernel/sched/fair.c | 19 +++++++++++++++++++ mm/memory.c | 3 +++ 4 files changed, 37 insertions(+) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 9f08a11b355c..215327daffae 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1686,6 +1686,16 @@ static inline int xchg_page_access_time(struct page *page, int time) last_time = page_cpupid_xchg_last(page, time >> PAGE_ACCESS_TIME_BUCKETS); return last_time << PAGE_ACCESS_TIME_BUCKETS; } + +static inline void vma_set_access_pid_bit(struct vm_area_struct *vma) +{ + unsigned int pid_bit; + + pid_bit = current->pid % BITS_PER_LONG; + if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids)) { + __set_bit(pid_bit, &vma->numab_state->access_pids); + } +} #else /* !CONFIG_NUMA_BALANCING */ static inline int page_cpupid_xchg_last(struct page *page, int cpupid) { @@ -1735,6 +1745,10 @@ static inline bool cpupid_match_pid(struct task_struct *task, int cpupid) { return false; } + +static inline void vma_set_access_pid_bit(struct vm_area_struct *vma) +{ +} #endif /* CONFIG_NUMA_BALANCING */ #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 3e1a42673769..f8cbd8efc7cb 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -477,6 +477,7 @@ struct vma_lock { struct vma_numab_state { unsigned long next_scan; + unsigned long access_pids; }; /* diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 7072de1686d5..ef27b5931480 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2928,6 +2928,21 @@ static void reset_ptenuma_scan(struct task_struct *p) p->mm->numa_scan_offset = 0; } +static bool vma_is_accessed(struct vm_area_struct *vma) +{ + /* + * Allow unconditional access first two times, so that all the (pages) + * of VMAs get prot_none fault introduced irrespective of accesses. + * This is also done to avoid any side effect of task scanning + * amplifying the unfairness of disjoint set of VMAs' access. + */ + if (READ_ONCE(current->mm->numa_scan_seq) < 2) + return true; + + return test_bit(current->pid % BITS_PER_LONG, + &vma->numab_state->access_pids); +} + /* * The expensive part of numa migration is done from task_work context. * Triggered from task_tick_numa(). @@ -3046,6 +3061,10 @@ static void task_numa_work(struct callback_head *work) vma->numab_state->next_scan)) continue; + /* Do not scan the VMA if task has not accessed */ + if (!vma_is_accessed(vma)) + continue; + do { start = max(start, vma->vm_start); end = ALIGN(start + (pages << PAGE_SHIFT), HPAGE_SIZE); diff --git a/mm/memory.c b/mm/memory.c index 9999574a9636..f77fccb5310c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4661,6 +4661,9 @@ int numa_migrate_prep(struct page *page, struct vm_area_struct *vma, { get_page(page); + /* Record the current PID acceesing VMA */ + vma_set_access_pid_bit(vma); + count_vm_numa_event(NUMA_HINT_FAULTS); if (page_nid == numa_node_id()) { count_vm_numa_event(NUMA_HINT_FAULTS_LOCAL); -- cgit v1.2.3 From 20f586486b87dcfe10b8c79398e24e720885588a Mon Sep 17 00:00:00 2001 From: Raghavendra K T Date: Wed, 1 Mar 2023 17:49:02 +0530 Subject: sched/numa: implement access PID reset logic This helps to ensure that only recently accessed PIDs scan the VMAs. Current implementation: (idea supported by PeterZ) 1. Accessing PID information is maintained in two windows. access_pids[1] being newest. 2. Reset old access PID info i.e. access_pid[0] every (4 * sysctl_numa_balancing_scan_delay) interval after initial scan delay period expires. The above interval seemed to be experimentally optimum since it avoids frequent reset of access info as well as helps clearing the old access info regularly. The reset logic is implemented in scan path. Link: https://lkml.kernel.org/r/f7a675f66d1442d048b4216b2baf94515012c405.1677672277.git.raghavendra.kt@amd.com Signed-off-by: Raghavendra K T Suggested-by: Mel Gorman Cc: Bharata B Rao Cc: David Hildenbrand Cc: Disha Talreja Cc: Ingo Molnar Cc: Mike Rapoport Cc: Peter Zijlstra Signed-off-by: Andrew Morton --- include/linux/mm.h | 4 ++-- include/linux/mm_types.h | 3 ++- kernel/sched/fair.c | 23 +++++++++++++++++++++-- 3 files changed, 25 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 215327daffae..e05a878e186e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1692,8 +1692,8 @@ static inline void vma_set_access_pid_bit(struct vm_area_struct *vma) unsigned int pid_bit; pid_bit = current->pid % BITS_PER_LONG; - if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids)) { - __set_bit(pid_bit, &vma->numab_state->access_pids); + if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids[1])) { + __set_bit(pid_bit, &vma->numab_state->access_pids[1]); } } #else /* !CONFIG_NUMA_BALANCING */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index f8cbd8efc7cb..092f842a854f 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -477,7 +477,8 @@ struct vma_lock { struct vma_numab_state { unsigned long next_scan; - unsigned long access_pids; + unsigned long next_pid_reset; + unsigned long access_pids[2]; }; /* diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index ef27b5931480..a962d4b60cd7 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2930,6 +2930,7 @@ static void reset_ptenuma_scan(struct task_struct *p) static bool vma_is_accessed(struct vm_area_struct *vma) { + unsigned long pids; /* * Allow unconditional access first two times, so that all the (pages) * of VMAs get prot_none fault introduced irrespective of accesses. @@ -2939,10 +2940,12 @@ static bool vma_is_accessed(struct vm_area_struct *vma) if (READ_ONCE(current->mm->numa_scan_seq) < 2) return true; - return test_bit(current->pid % BITS_PER_LONG, - &vma->numab_state->access_pids); + pids = vma->numab_state->access_pids[0] | vma->numab_state->access_pids[1]; + return test_bit(current->pid % BITS_PER_LONG, &pids); } +#define VMA_PID_RESET_PERIOD (4 * sysctl_numa_balancing_scan_delay) + /* * The expensive part of numa migration is done from task_work context. * Triggered from task_tick_numa(). @@ -3051,6 +3054,10 @@ static void task_numa_work(struct callback_head *work) vma->numab_state->next_scan = now + msecs_to_jiffies(sysctl_numa_balancing_scan_delay); + + /* Reset happens after 4 times scan delay of scan start */ + vma->numab_state->next_pid_reset = vma->numab_state->next_scan + + msecs_to_jiffies(VMA_PID_RESET_PERIOD); } /* @@ -3065,6 +3072,18 @@ static void task_numa_work(struct callback_head *work) if (!vma_is_accessed(vma)) continue; + /* + * RESET access PIDs regularly for old VMAs. Resetting after checking + * vma for recent access to avoid clearing PID info before access.. + */ + if (mm->numa_scan_seq && + time_after(jiffies, vma->numab_state->next_pid_reset)) { + vma->numab_state->next_pid_reset = vma->numab_state->next_pid_reset + + msecs_to_jiffies(VMA_PID_RESET_PERIOD); + vma->numab_state->access_pids[0] = READ_ONCE(vma->numab_state->access_pids[1]); + vma->numab_state->access_pids[1] = 0; + } + do { start = max(start, vma->vm_start); end = ALIGN(start + (pages << PAGE_SHIFT), HPAGE_SIZE); -- cgit v1.2.3 From d46031f40e0f7f7bf63914bb3f2e404ad3886ecd Mon Sep 17 00:00:00 2001 From: Raghavendra K T Date: Wed, 1 Mar 2023 17:49:03 +0530 Subject: sched/numa: use hash_32 to mix up PIDs accessing VMA before: last 6 bits of PID is used as index to store information about tasks accessing VMA's. after: hash_32 is used to take of cases where tasks are created over a period of time, and thus improve collision probability. Result: The patch series overall improves autonuma cost. Kernbench around more than 5% improvement and system time in mmtest autonuma showed more than 80% improvement Link: https://lkml.kernel.org/r/d5a9f75513300caed74e5c8570bba9317b963c2b.1677672277.git.raghavendra.kt@amd.com Signed-off-by: Raghavendra K T Suggested-by: Peter Zijlstra Cc: Bharata B Rao Cc: David Hildenbrand Cc: Disha Talreja Cc: Ingo Molnar Cc: Mel Gorman Cc: Mike Rapoport Signed-off-by: Andrew Morton --- include/linux/mm.h | 2 +- kernel/sched/fair.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index e05a878e186e..e249208f8fbe 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1691,7 +1691,7 @@ static inline void vma_set_access_pid_bit(struct vm_area_struct *vma) { unsigned int pid_bit; - pid_bit = current->pid % BITS_PER_LONG; + pid_bit = hash_32(current->pid, ilog2(BITS_PER_LONG)); if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids[1])) { __set_bit(pid_bit, &vma->numab_state->access_pids[1]); } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index a962d4b60cd7..db6fc9d978ae 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2941,7 +2941,7 @@ static bool vma_is_accessed(struct vm_area_struct *vma) return true; pids = vma->numab_state->access_pids[0] | vma->numab_state->access_pids[1]; - return test_bit(current->pid % BITS_PER_LONG, &pids); + return test_bit(hash_32(current->pid, ilog2(BITS_PER_LONG)), &pids); } #define VMA_PID_RESET_PERIOD (4 * sysctl_numa_balancing_scan_delay) -- cgit v1.2.3 From 5f300fd59a2ae90b8a7fb5ed3d5fd43768236c38 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 14 Apr 2023 10:03:53 +0200 Subject: mm: make arch_has_descending_max_zone_pfns() static clang produces a build failure on x86 for some randconfig builds after a change that moves around code to mm/mm_init.c: Cannot find symbol for section 2: .text. mm/mm_init.o: failed I have not been able to figure out why this happens, but the __weak annotation on arch_has_descending_max_zone_pfns() is the trigger here. Removing the weak function in favor of an open-coded Kconfig option check avoids the problem and becomes clearer as well as better to optimize by the compiler. [arnd@arndb.de: fix logic bug] Link: https://lkml.kernel.org/r/20230415081904.969049-1-arnd@kernel.org Link: https://lkml.kernel.org/r/20230414080418.110236-1-arnd@kernel.org Fixes: 9420f89db2dd ("mm: move most of core MM initialization to mm/mm_init.c") Signed-off-by: Arnd Bergmann Acked-by: Vlastimil Babka Tested-by: SeongJae Park Tested-by: Geert Uytterhoeven Acked-by: Mike Rapoport (IBM) Cc: kernel test robot Signed-off-by: Andrew Morton --- arch/arc/mm/init.c | 5 ----- include/linux/mm.h | 1 - mm/mm_init.c | 4 ++-- 3 files changed, 2 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index ce4e939a7f07..2b89b6c53801 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c @@ -74,11 +74,6 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size) base, TO_MB(size), !in_use ? "Not used":""); } -bool arch_has_descending_max_zone_pfns(void) -{ - return !IS_ENABLED(CONFIG_ARC_HAS_PAE40); -} - /* * First memory setup routine called from setup_arch() * 1. setup swapper's mm @init_mm diff --git a/include/linux/mm.h b/include/linux/mm.h index e249208f8fbe..5e5ef6ee4003 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3035,7 +3035,6 @@ extern void setup_per_cpu_pageset(void); extern int min_free_kbytes; extern int watermark_boost_factor; extern int watermark_scale_factor; -extern bool arch_has_descending_max_zone_pfns(void); /* nommu.c */ extern atomic_long_t mmap_pages_allocated; diff --git a/mm/mm_init.c b/mm/mm_init.c index dd3a6ed9663f..a0ec3b3acb5e 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -1752,9 +1752,9 @@ static void __init free_area_init_memoryless_node(int nid) * Some architectures, e.g. ARC may have ZONE_HIGHMEM below ZONE_NORMAL. For * such cases we allow max_zone_pfn sorted in the descending order */ -bool __weak arch_has_descending_max_zone_pfns(void) +static bool arch_has_descending_max_zone_pfns(void) { - return false; + return IS_ENABLED(CONFIG_ARC) && !IS_ENABLED(CONFIG_ARC_HAS_PAE40); } /** -- cgit v1.2.3 From 2ce0bdfebc74f6cbd4e97a4e767d505a81c38cf2 Mon Sep 17 00:00:00 2001 From: Ivan Orlov Date: Wed, 29 Mar 2023 18:53:30 +0400 Subject: mm: khugepaged: fix kernel BUG in hpage_collapse_scan_file() Syzkaller reported the following issue: kernel BUG at mm/khugepaged.c:1823! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 5097 Comm: syz-executor220 Not tainted 6.2.0-syzkaller-13154-g857f1268a591 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 RIP: 0010:collapse_file mm/khugepaged.c:1823 [inline] RIP: 0010:hpage_collapse_scan_file+0x67c8/0x7580 mm/khugepaged.c:2233 Code: 00 00 89 de e8 c9 66 a3 ff 31 ff 89 de e8 c0 66 a3 ff 45 84 f6 0f 85 28 0d 00 00 e8 22 64 a3 ff e9 dc f7 ff ff e8 18 64 a3 ff <0f> 0b f3 0f 1e fa e8 0d 64 a3 ff e9 93 f6 ff ff f3 0f 1e fa 4c 89 RSP: 0018:ffffc90003dff4e0 EFLAGS: 00010093 RAX: ffffffff81e95988 RBX: 00000000000001c1 RCX: ffff8880205b3a80 RDX: 0000000000000000 RSI: 00000000000001c0 RDI: 00000000000001c1 RBP: ffffc90003dff830 R08: ffffffff81e90e67 R09: fffffbfff1a433c3 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: ffffc90003dff6c0 R14: 00000000000001c0 R15: 0000000000000000 FS: 00007fdbae5ee700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdbae6901e0 CR3: 000000007b2dd000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: madvise_collapse+0x721/0xf50 mm/khugepaged.c:2693 madvise_vma_behavior mm/madvise.c:1086 [inline] madvise_walk_vmas mm/madvise.c:1260 [inline] do_madvise+0x9e5/0x4680 mm/madvise.c:1439 __do_sys_madvise mm/madvise.c:1452 [inline] __se_sys_madvise mm/madvise.c:1450 [inline] __x64_sys_madvise+0xa5/0xb0 mm/madvise.c:1450 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The xas_store() call during page cache scanning can potentially translate 'xas' into the error state (with the reproducer provided by the syzkaller the error code is -ENOMEM). However, there are no further checks after the 'xas_store', and the next call of 'xas_next' at the start of the scanning cycle doesn't increase the xa_index, and the issue occurs. This patch will add the xarray state error checking after the xas_store() and the corresponding result error code. Tested via syzbot. [akpm@linux-foundation.org: update include/trace/events/huge_memory.h's SCAN_STATUS] Link: https://lkml.kernel.org/r/20230329145330.23191-1-ivan.orlov0322@gmail.com Link: https://syzkaller.appspot.com/bug?id=7d6bb3760e026ece7524500fe44fb024a0e959fc Signed-off-by: Ivan Orlov Reported-by: syzbot+9578faa5475acb35fa50@syzkaller.appspotmail.com Tested-by: Zach O'Keefe Cc: Yang Shi Cc: Himadri Pandya Cc: Ivan Orlov Cc: Shuah Khan Cc: Song Liu Cc: Rik van Riel Cc: Kirill A. Shutemov Cc: Johannes Weiner Signed-off-by: Andrew Morton --- include/trace/events/huge_memory.h | 3 ++- mm/khugepaged.c | 20 ++++++++++++++++++++ 2 files changed, 22 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h index 3e6fb05852f9..c84c7af70158 100644 --- a/include/trace/events/huge_memory.h +++ b/include/trace/events/huge_memory.h @@ -36,7 +36,8 @@ EM( SCAN_ALLOC_HUGE_PAGE_FAIL, "alloc_huge_page_failed") \ EM( SCAN_CGROUP_CHARGE_FAIL, "ccgroup_charge_failed") \ EM( SCAN_TRUNCATED, "truncated") \ - EMe(SCAN_PAGE_HAS_PRIVATE, "page_has_private") \ + EM( SCAN_PAGE_HAS_PRIVATE, "page_has_private") \ + EMe(SCAN_STORE_FAILED, "store_failed") #undef EM #undef EMe diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 2c6548cd18a9..3b61cd188f7b 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -55,6 +55,7 @@ enum scan_result { SCAN_CGROUP_CHARGE_FAIL, SCAN_TRUNCATED, SCAN_PAGE_HAS_PRIVATE, + SCAN_STORE_FAILED, }; #define CREATE_TRACE_POINTS @@ -1857,6 +1858,15 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, goto xa_locked; } xas_store(&xas, hpage); + if (xas_error(&xas)) { + /* revert shmem_charge performed + * in the previous condition + */ + mapping->nrpages--; + shmem_uncharge(mapping->host, 1); + result = SCAN_STORE_FAILED; + goto xa_locked; + } nr_none++; continue; } @@ -2009,6 +2019,11 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, /* Finally, replace with the new page. */ xas_store(&xas, hpage); + /* We can't get an ENOMEM here (because the allocation happened before) + * but let's check for errors (XArray implementation can be + * changed in the future) + */ + WARN_ON_ONCE(xas_error(&xas)); continue; out_unlock: unlock_page(page); @@ -2046,6 +2061,11 @@ out_unlock: /* Join all the small entries into a single multi-index entry */ xas_set_order(&xas, start, HPAGE_PMD_ORDER); xas_store(&xas, hpage); + /* Here we can't get an ENOMEM (because entries were + * previously allocated) But let's check for errors + * (XArray implementation can be changed in the future) + */ + WARN_ON_ONCE(xas_error(&xas)); xa_locked: xas_unlock_irq(&xas); xa_unlocked: -- cgit v1.2.3 From a85c2257a8ac353af16dbcbf32c50d3380860bc5 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 17 Mar 2023 14:44:47 +0100 Subject: sched/isolation: add cpu_is_isolated() API Patch series "memcg, cpuisol: do not interfere pcp cache charges draining with cpuisol workloads". Leonardo has reported [1] that pcp memcg charge draining can interfere with cpu isolated workloads. The said draining is done from a WQ context with a pcp worker scheduled on each CPU which holds any cached charges for a specific memcg hierarchy. Operation is not really a common operation [2]. It can be triggered from the userspace though so some care is definitely due. Leonardo has tried to address the issue by allowing remote charge draining [3]. This approach requires an additional locking to synchronize pcp caches sync from a remote cpu from local pcp consumers. Even though the proposed lock was per-cpu there is still potential for contention and less predictable behavior. This patchset addresses the issue from a different angle. Rather than dealing with a potential synchronization, cpus which are isolated are simply never scheduled to be drained. This means that a small amount of charges could be laying around and waiting for a later use or they are flushed when a different memcg is charged from the same cpu. More details are in patch 2. The first patch from Frederic is implementing an abstraction to tell whether a specific cpu has been isolated and therefore require a special treatment. This patch (of 2): Provide this new API to check if a CPU has been isolated either through isolcpus= or nohz_full= kernel parameter. It aims at avoiding kernel load deemed to be safely spared on CPUs running sensitive workload that can't bear any disturbance, such as pcp cache draining. Link: https://lkml.kernel.org/r/20230317134448.11082-1-mhocko@kernel.org Link: https://lkml.kernel.org/r/20230317134448.11082-2-mhocko@kernel.org Signed-off-by: Frederic Weisbecker Signed-off-by: Michal Hocko Suggested-by: Michal Hocko Cc: Johannes Weiner Cc: Marcelo Tosatti Cc: Muchun Song Cc: Peter Zijlstra Cc: Roman Gushchin Cc: Shakeel Butt Cc: Thomas Gleixner Cc: Leonardo Bras Cc: Ingo Molnar Signed-off-by: Andrew Morton --- include/linux/sched/isolation.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include') diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h index 8c15abd67aed..fe1a46f30d24 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -46,6 +46,12 @@ static inline bool housekeeping_enabled(enum hk_type type) static inline void housekeeping_affine(struct task_struct *t, enum hk_type type) { } + +static inline bool housekeeping_test_cpu(int cpu, enum hk_type type) +{ + return true; +} + static inline void housekeeping_init(void) { } #endif /* CONFIG_CPU_ISOLATION */ @@ -58,4 +64,10 @@ static inline bool housekeeping_cpu(int cpu, enum hk_type type) return true; } +static inline bool cpu_is_isolated(int cpu) +{ + return !housekeeping_test_cpu(cpu, HK_TYPE_DOMAIN) || + !housekeeping_test_cpu(cpu, HK_TYPE_TICK); +} + #endif /* _LINUX_SCHED_ISOLATION_H */ -- cgit v1.2.3 From 957ebbdf434013ee01f29f6c9174eced995ebbe7 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 27 Mar 2023 16:10:50 +0100 Subject: hugetlb: remove PageHeadHuge() Sidhartha Kumar removed the last caller of PageHeadHuge(), so we can now remove it and make folio_test_hugetlb() the real implementation. Add kernel-doc for folio_test_hugetlb(). Link: https://lkml.kernel.org/r/20230327151050.1787744-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Sidhartha Kumar Reviewed-by: Mike Kravetz Reviewed-by: David Hildenbrand Reviewed-by: Muchun Song Signed-off-by: Andrew Morton --- include/linux/page-flags.h | 7 +------ mm/hugetlb.c | 18 +++++++++++------- 2 files changed, 12 insertions(+), 13 deletions(-) (limited to 'include') diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index dcda20c47b8f..efc42fae3d96 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -815,14 +815,9 @@ static inline void ClearPageCompound(struct page *page) #ifdef CONFIG_HUGETLB_PAGE int PageHuge(struct page *page); -int PageHeadHuge(struct page *page); -static inline bool folio_test_hugetlb(struct folio *folio) -{ - return PageHeadHuge(&folio->page); -} +bool folio_test_hugetlb(struct folio *folio); #else TESTPAGEFLAG_FALSE(Huge, hugetlb) -TESTPAGEFLAG_FALSE(HeadHuge, headhuge) #endif #ifdef CONFIG_TRANSPARENT_HUGEPAGE diff --git a/mm/hugetlb.c b/mm/hugetlb.c index a58b3739ed4b..7e4a80769c9e 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2050,19 +2050,23 @@ int PageHuge(struct page *page) } EXPORT_SYMBOL_GPL(PageHuge); -/* - * PageHeadHuge() only returns true for hugetlbfs head page, but not for - * normal or transparent huge pages. +/** + * folio_test_hugetlb - Determine if the folio belongs to hugetlbfs + * @folio: The folio to test. + * + * Context: Any context. Caller should have a reference on the folio to + * prevent it from being turned into a tail page. + * Return: True for hugetlbfs folios, false for anon folios or folios + * belonging to other filesystems. */ -int PageHeadHuge(struct page *page_head) +bool folio_test_hugetlb(struct folio *folio) { - struct folio *folio = (struct folio *)page_head; if (!folio_test_large(folio)) - return 0; + return false; return folio->_folio_dtor == HUGETLB_PAGE_DTOR; } -EXPORT_SYMBOL_GPL(PageHeadHuge); +EXPORT_SYMBOL_GPL(folio_test_hugetlb); /* * Find and lock address space (mapping) in write mode. -- cgit v1.2.3 From 62f31bd4dcedffe3c919deb76ed65bf62c3cf80b Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (IBM)" Date: Sun, 26 Mar 2023 19:02:15 +0300 Subject: mm: move free_area_empty() to mm/internal.h The free_area_empty() helper is only used inside mm/ so move it there to reduce noise in include/linux/mmzone.h Link: https://lkml.kernel.org/r/20230326160215.2674531-1-rppt@kernel.org Signed-off-by: Mike Rapoport (IBM) Suggested-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 5 ----- mm/internal.h | 5 +++++ 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 2d22e47dc1eb..337956748976 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -110,11 +110,6 @@ struct free_area { unsigned long nr_free; }; -static inline bool free_area_empty(struct free_area *area, int migratetype) -{ - return list_empty(&area->free_list[migratetype]); -} - struct pglist_data; #ifdef CONFIG_NUMA diff --git a/mm/internal.h b/mm/internal.h index 73b167b59cc5..92ddd3a05b74 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -517,6 +517,11 @@ void init_cma_reserved_pageblock(struct page *page); int find_suitable_fallback(struct free_area *area, unsigned int order, int migratetype, bool only_stealable, bool *can_steal); +static inline bool free_area_empty(struct free_area *area, int migratetype) +{ + return list_empty(&area->free_list[migratetype]); +} + /* * These three helpers classifies VMAs for virtual memory accounting. */ -- cgit v1.2.3 From 8bff9a04ca33476213ea6155850505787c540c25 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Thu, 30 Mar 2023 19:17:54 +0000 Subject: cgroup: rename cgroup_rstat_flush_"irqsafe" to "atomic" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch series "memcg: avoid flushing stats atomically where possible", v3. rstat flushing is an expensive operation that scales with the number of cpus and the number of cgroups in the system. The purpose of this series is to minimize the contexts where we flush stats atomically. Patches 1 and 2 are cleanups requested during reviews of prior versions of this series. Patch 3 makes sure we never try to flush from within an irq context. Patches 4 to 7 introduce separate variants of mem_cgroup_flush_stats() for atomic and non-atomic flushing, and make sure we only flush the stats atomically when necessary. Patch 8 is a slightly tangential optimization that limits the work done by rstat flushing in some scenarios. This patch (of 8): cgroup_rstat_flush_irqsafe() can be a confusing name. It may read as "irqs are disabled throughout", which is what the current implementation does (currently under discussion [1]), but is not the intention. The intention is that this function is safe to call from atomic contexts. Name it as such. Link: https://lkml.kernel.org/r/20230330191801.1967435-1-yosryahmed@google.com Link: https://lkml.kernel.org/r/20230330191801.1967435-2-yosryahmed@google.com Signed-off-by: Yosry Ahmed Suggested-by: Johannes Weiner Acked-by: Shakeel Butt Acked-by: Johannes Weiner Cc: Jens Axboe Cc: Josef Bacik Cc: Michal Hocko Cc: Michal Koutný Cc: Muchun Song Cc: Roman Gushchin Cc: Tejun Heo Cc: Vasily Averin Cc: Zefan Li Cc: Michal Hocko Signed-off-by: Andrew Morton --- include/linux/cgroup.h | 2 +- kernel/cgroup/rstat.c | 4 ++-- mm/memcontrol.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 3410aecffdb4..885f5395fcd0 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -692,7 +692,7 @@ static inline void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen) */ void cgroup_rstat_updated(struct cgroup *cgrp, int cpu); void cgroup_rstat_flush(struct cgroup *cgrp); -void cgroup_rstat_flush_irqsafe(struct cgroup *cgrp); +void cgroup_rstat_flush_atomic(struct cgroup *cgrp); void cgroup_rstat_flush_hold(struct cgroup *cgrp); void cgroup_rstat_flush_release(void); diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c index 831f1f472bb8..d3252b0416b6 100644 --- a/kernel/cgroup/rstat.c +++ b/kernel/cgroup/rstat.c @@ -241,12 +241,12 @@ __bpf_kfunc void cgroup_rstat_flush(struct cgroup *cgrp) } /** - * cgroup_rstat_flush_irqsafe - irqsafe version of cgroup_rstat_flush() + * cgroup_rstat_flush_atomic- atomic version of cgroup_rstat_flush() * @cgrp: target cgroup * * This function can be called from any context. */ -void cgroup_rstat_flush_irqsafe(struct cgroup *cgrp) +void cgroup_rstat_flush_atomic(struct cgroup *cgrp) { unsigned long flags; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 681e7528a714..b7c3eab6b4fe 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -643,7 +643,7 @@ static void __mem_cgroup_flush_stats(void) return; flush_next_time = jiffies_64 + 2*FLUSH_TIME; - cgroup_rstat_flush_irqsafe(root_mem_cgroup->css.cgroup); + cgroup_rstat_flush_atomic(root_mem_cgroup->css.cgroup); atomic_set(&stats_flush_threshold, 0); spin_unlock_irqrestore(&stats_flush_lock, flag); } -- cgit v1.2.3 From 92fbbc7202ac4fb16250dc91c88211814ae2190b Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Thu, 30 Mar 2023 19:17:55 +0000 Subject: memcg: rename mem_cgroup_flush_stats_"delayed" to "ratelimited" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit mem_cgroup_flush_stats_delayed() suggests his is using a delayed_work, but this is actually sometimes flushing directly from the callsite. What it's doing is ratelimited calls. A better name would be mem_cgroup_flush_stats_ratelimited(). Link: https://lkml.kernel.org/r/20230330191801.1967435-3-yosryahmed@google.com Signed-off-by: Yosry Ahmed Suggested-by: Johannes Weiner Acked-by: Shakeel Butt Acked-by: Johannes Weiner Acked-by: Michal Hocko Cc: Jens Axboe Cc: Josef Bacik Cc: Michal Hocko Cc: Michal Koutný Cc: Muchun Song Cc: Roman Gushchin Cc: Tejun Heo Cc: Vasily Averin Cc: Zefan Li Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 4 ++-- mm/memcontrol.c | 2 +- mm/workingset.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index aa69ea98e2d8..00a88cf947e1 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1038,7 +1038,7 @@ static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec, } void mem_cgroup_flush_stats(void); -void mem_cgroup_flush_stats_delayed(void); +void mem_cgroup_flush_stats_ratelimited(void); void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val); @@ -1536,7 +1536,7 @@ static inline void mem_cgroup_flush_stats(void) { } -static inline void mem_cgroup_flush_stats_delayed(void) +static inline void mem_cgroup_flush_stats_ratelimited(void) { } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index b7c3eab6b4fe..a01f062e7007 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -654,7 +654,7 @@ void mem_cgroup_flush_stats(void) __mem_cgroup_flush_stats(); } -void mem_cgroup_flush_stats_delayed(void) +void mem_cgroup_flush_stats_ratelimited(void) { if (time_after64(jiffies_64, flush_next_time)) mem_cgroup_flush_stats(); diff --git a/mm/workingset.c b/mm/workingset.c index 00c6f4d9d9be..af862c6738c3 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -462,7 +462,7 @@ void workingset_refault(struct folio *folio, void *shadow) mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr); - mem_cgroup_flush_stats_delayed(); + mem_cgroup_flush_stats_ratelimited(); /* * Compare the distance to the existing workingset size. We * don't activate pages that couldn't stay resident even if -- cgit v1.2.3 From 9fad9aee1f267a8ad1f86b87ae70b2c4d6796164 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Thu, 30 Mar 2023 19:17:58 +0000 Subject: memcg: sleep during flushing stats in safe contexts MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, all contexts that flush memcg stats do so with sleeping not allowed. Some of these contexts are perfectly safe to sleep in, such as reading cgroup files from userspace or the background periodic flusher. Flushing is an expensive operation that scales with the number of cpus and the number of cgroups in the system, so avoid doing it atomically where possible. Refactor the code to make mem_cgroup_flush_stats() non-atomic (aka sleepable), and provide a separate atomic version. The atomic version is used in reclaim, refault, writeback, and in mem_cgroup_usage(). All other code paths are left to use the non-atomic version. This includes callbacks for userspace reads and the periodic flusher. Since refault is the only caller of mem_cgroup_flush_stats_ratelimited(), change it to mem_cgroup_flush_stats_atomic_ratelimited(). Reclaim and refault code paths are modified to do non-atomic flushing in separate later patches -- so it will eventually be changed back to mem_cgroup_flush_stats_ratelimited(). Link: https://lkml.kernel.org/r/20230330191801.1967435-6-yosryahmed@google.com Signed-off-by: Yosry Ahmed Acked-by: Shakeel Butt Acked-by: Michal Hocko Acked-by: Johannes Weiner Cc: Jens Axboe Cc: Josef Bacik Cc: Michal Hocko Cc: Michal Koutný Cc: Muchun Song Cc: Roman Gushchin Cc: Tejun Heo Cc: Vasily Averin Cc: Zefan Li Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 9 +++++++-- mm/memcontrol.c | 45 ++++++++++++++++++++++++++++++++++++--------- mm/vmscan.c | 2 +- mm/workingset.c | 2 +- 4 files changed, 45 insertions(+), 13 deletions(-) (limited to 'include') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 00a88cf947e1..3db355e6677f 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1038,7 +1038,8 @@ static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec, } void mem_cgroup_flush_stats(void); -void mem_cgroup_flush_stats_ratelimited(void); +void mem_cgroup_flush_stats_atomic(void); +void mem_cgroup_flush_stats_atomic_ratelimited(void); void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val); @@ -1536,7 +1537,11 @@ static inline void mem_cgroup_flush_stats(void) { } -static inline void mem_cgroup_flush_stats_ratelimited(void) +static inline void mem_cgroup_flush_stats_atomic(void) +{ +} + +static inline void mem_cgroup_flush_stats_atomic_ratelimited(void) { } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index a9f18456a16b..06786dea50b8 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -635,7 +635,7 @@ static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) } } -static void __mem_cgroup_flush_stats(void) +static void do_flush_stats(bool atomic) { /* * We always flush the entire tree, so concurrent flushers can just @@ -647,26 +647,46 @@ static void __mem_cgroup_flush_stats(void) return; WRITE_ONCE(flush_next_time, jiffies_64 + 2*FLUSH_TIME); - cgroup_rstat_flush_atomic(root_mem_cgroup->css.cgroup); + + if (atomic) + cgroup_rstat_flush_atomic(root_mem_cgroup->css.cgroup); + else + cgroup_rstat_flush(root_mem_cgroup->css.cgroup); + atomic_set(&stats_flush_threshold, 0); atomic_set(&stats_flush_ongoing, 0); } +static bool should_flush_stats(void) +{ + return atomic_read(&stats_flush_threshold) > num_online_cpus(); +} + void mem_cgroup_flush_stats(void) { - if (atomic_read(&stats_flush_threshold) > num_online_cpus()) - __mem_cgroup_flush_stats(); + if (should_flush_stats()) + do_flush_stats(false); } -void mem_cgroup_flush_stats_ratelimited(void) +void mem_cgroup_flush_stats_atomic(void) +{ + if (should_flush_stats()) + do_flush_stats(true); +} + +void mem_cgroup_flush_stats_atomic_ratelimited(void) { if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) - mem_cgroup_flush_stats(); + mem_cgroup_flush_stats_atomic(); } static void flush_memcg_stats_dwork(struct work_struct *w) { - __mem_cgroup_flush_stats(); + /* + * Always flush here so that flushing in latency-sensitive paths is + * as cheap as possible. + */ + do_flush_stats(false); queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME); } @@ -3686,9 +3706,12 @@ static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) * done from irq context; use stale stats in this case. * Arguably, usage threshold events are not reliable on the root * memcg anyway since its usage is ill-defined. + * + * Additionally, other call paths through memcg_check_events() + * disable irqs, so make sure we are flushing stats atomically. */ if (in_task()) - mem_cgroup_flush_stats(); + mem_cgroup_flush_stats_atomic(); val = memcg_page_state(memcg, NR_FILE_PAGES) + memcg_page_state(memcg, NR_ANON_MAPPED); if (swap) @@ -4611,7 +4634,11 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); struct mem_cgroup *parent; - mem_cgroup_flush_stats(); + /* + * wb_writeback() takes a spinlock and calls + * wb_over_bg_thresh()->mem_cgroup_wb_stats(). Do not sleep. + */ + mem_cgroup_flush_stats_atomic(); *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); diff --git a/mm/vmscan.c b/mm/vmscan.c index 98719e72b5e2..c68db50ec109 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2861,7 +2861,7 @@ static void prepare_scan_count(pg_data_t *pgdat, struct scan_control *sc) * Flush the memory cgroup stats, so that we read accurate per-memcg * lruvec stats for heuristics. */ - mem_cgroup_flush_stats(); + mem_cgroup_flush_stats_atomic(); /* * Determine the scan balance between anon and file LRUs. diff --git a/mm/workingset.c b/mm/workingset.c index af862c6738c3..dab0c362b9e3 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -462,7 +462,7 @@ void workingset_refault(struct folio *folio, void *shadow) mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr); - mem_cgroup_flush_stats_ratelimited(); + mem_cgroup_flush_stats_atomic_ratelimited(); /* * Compare the distance to the existing workingset size. We * don't activate pages that couldn't stay resident even if -- cgit v1.2.3 From 4009b2f1887036d30637bc06dd0ade7e18408bb3 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Thu, 30 Mar 2023 19:17:59 +0000 Subject: workingset: memcg: sleep when flushing stats in workingset_refault() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In workingset_refault(), we call mem_cgroup_flush_stats_atomic_ratelimited() to read accurate stats within an RCU read section and with sleeping disallowed. Move the call above the RCU read section to make it non-atomic. Flushing is an expensive operation that scales with the number of cpus and the number of cgroups in the system, so avoid doing it atomically where possible. Since workingset_refault() is the only caller of mem_cgroup_flush_stats_atomic_ratelimited(), just make it non-atomic, and rename it to mem_cgroup_flush_stats_ratelimited(). Link: https://lkml.kernel.org/r/20230330191801.1967435-7-yosryahmed@google.com Signed-off-by: Yosry Ahmed Acked-by: Shakeel Butt Acked-by: Johannes Weiner Acked-by: Michal Hocko Cc: Jens Axboe Cc: Josef Bacik Cc: Michal Hocko Cc: Michal Koutný Cc: Muchun Song Cc: Roman Gushchin Cc: Tejun Heo Cc: Vasily Averin Cc: Zefan Li Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 4 ++-- mm/memcontrol.c | 4 ++-- mm/workingset.c | 5 +++-- 3 files changed, 7 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 3db355e6677f..222d7370134c 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1039,7 +1039,7 @@ static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec, void mem_cgroup_flush_stats(void); void mem_cgroup_flush_stats_atomic(void); -void mem_cgroup_flush_stats_atomic_ratelimited(void); +void mem_cgroup_flush_stats_ratelimited(void); void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val); @@ -1541,7 +1541,7 @@ static inline void mem_cgroup_flush_stats_atomic(void) { } -static inline void mem_cgroup_flush_stats_atomic_ratelimited(void) +static inline void mem_cgroup_flush_stats_ratelimited(void) { } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 06786dea50b8..e9e79ceb9a11 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -674,10 +674,10 @@ void mem_cgroup_flush_stats_atomic(void) do_flush_stats(true); } -void mem_cgroup_flush_stats_atomic_ratelimited(void) +void mem_cgroup_flush_stats_ratelimited(void) { if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) - mem_cgroup_flush_stats_atomic(); + mem_cgroup_flush_stats(); } static void flush_memcg_stats_dwork(struct work_struct *w) diff --git a/mm/workingset.c b/mm/workingset.c index dab0c362b9e3..3025beee9b34 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -406,6 +406,9 @@ void workingset_refault(struct folio *folio, void *shadow) unpack_shadow(shadow, &memcgid, &pgdat, &eviction, &workingset); eviction <<= bucket_order; + /* Flush stats (and potentially sleep) before holding RCU read lock */ + mem_cgroup_flush_stats_ratelimited(); + rcu_read_lock(); /* * Look up the memcg associated with the stored ID. It might @@ -461,8 +464,6 @@ void workingset_refault(struct folio *folio, void *shadow) lruvec = mem_cgroup_lruvec(memcg, pgdat); mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr); - - mem_cgroup_flush_stats_atomic_ratelimited(); /* * Compare the distance to the existing workingset size. We * don't activate pages that couldn't stay resident even if -- cgit v1.2.3 From 98c76c9f1ef7599b39bfd4bd99b8a760d4a8cd3b Mon Sep 17 00:00:00 2001 From: Jiaqi Yan Date: Wed, 29 Mar 2023 08:11:19 -0700 Subject: mm/khugepaged: recover from poisoned anonymous memory MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Problem ======= Memory DIMMs are subject to multi-bit flips, i.e. memory errors. As memory size and density increase, the chances of and number of memory errors increase. The increasing size and density of server RAM in the data center and cloud have shown increased uncorrectable memory errors. There are already mechanisms in the kernel to recover from uncorrectable memory errors. This series of patches provides the recovery mechanism for the particular kernel agent khugepaged when it collapses memory pages. Impact ====== The main reason we chose to make khugepaged collapsing tolerant of memory failures was its high possibility of accessing poisoned memory while performing functionally optional compaction actions. Standard applications typically don't have strict requirements on the size of its pages. So they are given 4K pages by the kernel. The kernel is able to improve application performance by either 1) giving applications 2M pages to begin with, or 2) collapsing 4K pages into 2M pages when possible. This collapsing operation is done by khugepaged, a kernel agent that is constantly scanning memory. When collapsing 4K pages into a 2M page, it must copy the data from the 4K pages into a physically contiguous 2M page. Therefore, as long as there exists one poisoned cache line in collapsible 4K pages, khugepaged will eventually access it. The current impact to users is a machine check exception triggered kernel panic. However, khugepaged’s compaction operations are not functionally required kernel actions. Therefore making khugepaged tolerant to poisoned memory will greatly improve user experience. This patch series is for cases where khugepaged is the first guy that detects the memory errors on the poisoned pages. IOW, the pages are not known to have memory errors when khugepaged collapsing gets to them. In our observation, this happens frequently when the huge page ratio of the system is relatively low, which is fairly common in virtual machines running on cloud. Solution ======== As stated before, it is less desirable to crash the system only because khugepaged accesses poisoned pages while it is collapsing 4K pages. The high level idea of this patch series is to skip the group of pages (usually 512 4K-size pages) once khugepaged finds one of them is poisoned, as these pages have become ineligible to be collapsed. We are also careful to unwind operations khuagepaged has performed before it detects memory failures. For example, before copying and collapsing a group of anonymous pages into a huge page, the source pages will be isolated and their page table is unlinked from their PMD. These operations need to be undone in order to ensure these pages are not changed/lost from the perspective of other threads (both user and kernel space). As for file backed memory pages, there already exists a rollback case. This patch just extends it so that khugepaged also correctly rolls back when it fails to copy poisoned 4K pages. This patch (of 3): Make __collapse_huge_page_copy return whether copying anonymous pages succeeded, and make collapse_huge_page handle the return status. Break existing PTE scan loop into two for-loops. The first loop copies source pages into target huge page, and can fail gracefully when running into memory errors in source pages. If copying all pages succeeds, the second loop releases and clears up these normal pages. Otherwise, the second loop rolls back the page table and page states by: - re-establishing the original PTEs-to-PMD connection. - releasing source pages back to their LRU list. Tested manually: 0. Enable khugepaged on system under test. 1. Start a two-thread application. Each thread allocates a chunk of non-huge anonymous memory buffer. 2. Pick 4 random buffer locations (2 in each thread) and inject uncorrectable memory errors at corresponding physical addresses. 3. Signal both threads to make their memory buffer collapsible, i.e. calling madvise(MADV_HUGEPAGE). 4. Wait and check kernel log: khugepaged is able to recover from poisoned pages and skips collapsing them. 5. Signal both threads to inspect their buffer contents and make sure no data corruption. Link: https://lkml.kernel.org/r/20230329151121.949896-1-jiaqiyan@google.com Link: https://lkml.kernel.org/r/20230329151121.949896-2-jiaqiyan@google.com Signed-off-by: Jiaqi Yan Cc: David Stevens Cc: Hugh Dickins Cc: Kefeng Wang Cc: Kirill A. Shutemov Cc: "Kirill A. Shutemov" Cc: Miaohe Lin Cc: Naoya Horiguchi Cc: Oscar Salvador Cc: Tong Tiangen Cc: Tony Luck Cc: Yang Shi Signed-off-by: Andrew Morton --- include/trace/events/huge_memory.h | 3 +- mm/khugepaged.c | 112 ++++++++++++++++++++++++++++++++----- 2 files changed, 101 insertions(+), 14 deletions(-) (limited to 'include') diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h index c84c7af70158..eca4c6f3625e 100644 --- a/include/trace/events/huge_memory.h +++ b/include/trace/events/huge_memory.h @@ -37,7 +37,8 @@ EM( SCAN_CGROUP_CHARGE_FAIL, "ccgroup_charge_failed") \ EM( SCAN_TRUNCATED, "truncated") \ EM( SCAN_PAGE_HAS_PRIVATE, "page_has_private") \ - EMe(SCAN_STORE_FAILED, "store_failed") + EM( SCAN_STORE_FAILED, "store_failed") \ + EMe(SCAN_COPY_MC, "copy_poisoned_page") #undef EM #undef EMe diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 3b61cd188f7b..c66933d8a8b8 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -56,6 +56,7 @@ enum scan_result { SCAN_TRUNCATED, SCAN_PAGE_HAS_PRIVATE, SCAN_STORE_FAILED, + SCAN_COPY_MC, }; #define CREATE_TRACE_POINTS @@ -686,20 +687,21 @@ out: return result; } -static void __collapse_huge_page_copy(pte_t *pte, struct page *page, - struct vm_area_struct *vma, - unsigned long address, - spinlock_t *ptl, - struct list_head *compound_pagelist) +static void __collapse_huge_page_copy_succeeded(pte_t *pte, + struct vm_area_struct *vma, + unsigned long address, + spinlock_t *ptl, + struct list_head *compound_pagelist) { - struct page *src_page, *tmp; + struct page *src_page; + struct page *tmp; pte_t *_pte; - for (_pte = pte; _pte < pte + HPAGE_PMD_NR; - _pte++, page++, address += PAGE_SIZE) { - pte_t pteval = *_pte; + pte_t pteval; + for (_pte = pte; _pte < pte + HPAGE_PMD_NR; + _pte++, address += PAGE_SIZE) { + pteval = *_pte; if (pte_none(pteval) || is_zero_pfn(pte_pfn(pteval))) { - clear_user_highpage(page, address); add_mm_counter(vma->vm_mm, MM_ANONPAGES, 1); if (is_zero_pfn(pte_pfn(pteval))) { /* @@ -711,7 +713,6 @@ static void __collapse_huge_page_copy(pte_t *pte, struct page *page, } } else { src_page = pte_page(pteval); - copy_user_highpage(page, src_page, address, vma); if (!PageCompound(src_page)) release_pte_page(src_page); /* @@ -738,6 +739,87 @@ static void __collapse_huge_page_copy(pte_t *pte, struct page *page, } } +static void __collapse_huge_page_copy_failed(pte_t *pte, + pmd_t *pmd, + pmd_t orig_pmd, + struct vm_area_struct *vma, + struct list_head *compound_pagelist) +{ + spinlock_t *pmd_ptl; + + /* + * Re-establish the PMD to point to the original page table + * entry. Restoring PMD needs to be done prior to releasing + * pages. Since pages are still isolated and locked here, + * acquiring anon_vma_lock_write is unnecessary. + */ + pmd_ptl = pmd_lock(vma->vm_mm, pmd); + pmd_populate(vma->vm_mm, pmd, pmd_pgtable(orig_pmd)); + spin_unlock(pmd_ptl); + /* + * Release both raw and compound pages isolated + * in __collapse_huge_page_isolate. + */ + release_pte_pages(pte, pte + HPAGE_PMD_NR, compound_pagelist); +} + +/* + * __collapse_huge_page_copy - attempts to copy memory contents from raw + * pages to a hugepage. Cleans up the raw pages if copying succeeds; + * otherwise restores the original page table and releases isolated raw pages. + * Returns SCAN_SUCCEED if copying succeeds, otherwise returns SCAN_COPY_MC. + * + * @pte: starting of the PTEs to copy from + * @page: the new hugepage to copy contents to + * @pmd: pointer to the new hugepage's PMD + * @orig_pmd: the original raw pages' PMD + * @vma: the original raw pages' virtual memory area + * @address: starting address to copy + * @ptl: lock on raw pages' PTEs + * @compound_pagelist: list that stores compound pages + */ +static int __collapse_huge_page_copy(pte_t *pte, + struct page *page, + pmd_t *pmd, + pmd_t orig_pmd, + struct vm_area_struct *vma, + unsigned long address, + spinlock_t *ptl, + struct list_head *compound_pagelist) +{ + struct page *src_page; + pte_t *_pte; + pte_t pteval; + unsigned long _address; + int result = SCAN_SUCCEED; + + /* + * Copying pages' contents is subject to memory poison at any iteration. + */ + for (_pte = pte, _address = address; _pte < pte + HPAGE_PMD_NR; + _pte++, page++, _address += PAGE_SIZE) { + pteval = *_pte; + if (pte_none(pteval) || is_zero_pfn(pte_pfn(pteval))) { + clear_user_highpage(page, _address); + continue; + } + src_page = pte_page(pteval); + if (copy_mc_user_highpage(page, src_page, _address, vma) > 0) { + result = SCAN_COPY_MC; + break; + } + } + + if (likely(result == SCAN_SUCCEED)) + __collapse_huge_page_copy_succeeded(pte, vma, address, ptl, + compound_pagelist); + else + __collapse_huge_page_copy_failed(pte, pmd, orig_pmd, vma, + compound_pagelist); + + return result; +} + static void khugepaged_alloc_sleep(void) { DEFINE_WAIT(wait); @@ -1111,9 +1193,13 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, */ anon_vma_unlock_write(vma->anon_vma); - __collapse_huge_page_copy(pte, hpage, vma, address, pte_ptl, - &compound_pagelist); + result = __collapse_huge_page_copy(pte, hpage, pmd, _pmd, + vma, address, pte_ptl, + &compound_pagelist); pte_unmap(pte); + if (unlikely(result != SCAN_SUCCEED)) + goto out_up_write; + /* * spin_lock() below is not the equivalent of smp_wmb(), but * the smp_wmb() inside __SetPageUptodate() can be reused to -- cgit v1.2.3 From 6efc7afb5cc98488410d44695685d003d832534d Mon Sep 17 00:00:00 2001 From: Jiaqi Yan Date: Wed, 29 Mar 2023 08:11:20 -0700 Subject: mm/hwpoison: introduce copy_mc_highpage Similar to how copy_mc_user_highpage is implemented for copy_user_highpage on #MC supported architecture, introduce the #MC handled version of copy_highpage. This helper has immediate usage when khugepaged wants to copy file-backed memory pages and tolerate #MC. Link: https://lkml.kernel.org/r/20230329151121.949896-3-jiaqiyan@google.com Signed-off-by: Jiaqi Yan Reviewed-by: Yang Shi Cc: David Stevens Cc: Hugh Dickins Cc: Kefeng Wang Cc: Kirill A. Shutemov Cc: "Kirill A. Shutemov" Cc: Miaohe Lin Cc: Naoya Horiguchi Cc: Oscar Salvador Cc: Tong Tiangen Cc: Tony Luck Signed-off-by: Andrew Morton --- include/linux/highmem.h | 54 +++++++++++++++++++++++++++++++++++++------------ 1 file changed, 41 insertions(+), 13 deletions(-) (limited to 'include') diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 9c7cdaa3de8c..4de1dbcd3ef6 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -315,7 +315,29 @@ static inline void copy_user_highpage(struct page *to, struct page *from, #endif +#ifndef __HAVE_ARCH_COPY_HIGHPAGE + +static inline void copy_highpage(struct page *to, struct page *from) +{ + char *vfrom, *vto; + + vfrom = kmap_local_page(from); + vto = kmap_local_page(to); + copy_page(vto, vfrom); + kmsan_copy_page_meta(to, from); + kunmap_local(vto); + kunmap_local(vfrom); +} + +#endif + #ifdef copy_mc_to_kernel +/* + * If architecture supports machine check exception handling, define the + * #MC versions of copy_user_highpage and copy_highpage. They copy a memory + * page with #MC in source page (@from) handled, and return the number + * of bytes not copied if there was a #MC, otherwise 0 for success. + */ static inline int copy_mc_user_highpage(struct page *to, struct page *from, unsigned long vaddr, struct vm_area_struct *vma) { @@ -332,29 +354,35 @@ static inline int copy_mc_user_highpage(struct page *to, struct page *from, return ret; } -#else -static inline int copy_mc_user_highpage(struct page *to, struct page *from, - unsigned long vaddr, struct vm_area_struct *vma) -{ - copy_user_highpage(to, from, vaddr, vma); - return 0; -} -#endif -#ifndef __HAVE_ARCH_COPY_HIGHPAGE - -static inline void copy_highpage(struct page *to, struct page *from) +static inline int copy_mc_highpage(struct page *to, struct page *from) { + unsigned long ret; char *vfrom, *vto; vfrom = kmap_local_page(from); vto = kmap_local_page(to); - copy_page(vto, vfrom); - kmsan_copy_page_meta(to, from); + ret = copy_mc_to_kernel(vto, vfrom, PAGE_SIZE); + if (!ret) + kmsan_copy_page_meta(to, from); kunmap_local(vto); kunmap_local(vfrom); + + return ret; +} +#else +static inline int copy_mc_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) +{ + copy_user_highpage(to, from, vaddr, vma); + return 0; } +static inline int copy_mc_highpage(struct page *to, struct page *from) +{ + copy_highpage(to, from); + return 0; +} #endif static inline void memcpy_page(struct page *dst_page, size_t dst_off, -- cgit v1.2.3 From ac492b9c70cac4d887e9dce4410b1d521851e142 Mon Sep 17 00:00:00 2001 From: David Stevens Date: Tue, 4 Apr 2023 21:01:16 +0900 Subject: mm/khugepaged: skip shmem with userfaultfd Make sure that collapse_file respects any userfaultfds registered with MODE_MISSING. If userspace has any such userfaultfds registered, then for any page which it knows to be missing, it may expect a UFFD_EVENT_PAGEFAULT. This means collapse_file needs to be careful when collapsing a shmem range would result in replacing an empty page with a THP, to avoid breaking userfaultfd. Synchronization when checking for userfaultfds in collapse_file is tricky because the mmap locks can't be used to prevent races with the registration of new userfaultfds. Instead, we provide synchronization by ensuring that userspace cannot observe the fact that pages are missing before we check for userfaultfds. Although this allows registration of a userfaultfd to race with collapse_file, it ensures that userspace cannot observe any pages transition from missing to present after such a race occurs. This makes such a race indistinguishable to the collapse occurring immediately before the userfaultfd registration. The first step to provide this synchronization is to stop filling gaps during the loop iterating over the target range, since the page cache lock can be dropped during that loop. The second step is to fill the gaps with XA_RETRY_ENTRY after the page cache lock is acquired the final time, to avoid races with accesses to the page cache that only take the RCU read lock. The fact that we don't fill holes during the initial iteration means that collapse_file now has to handle faults occurring during the collapse. This is done by re-validating the number of missing pages after acquiring the page cache lock for the final time. This fix is targeted at khugepaged, but the change also applies to MADV_COLLAPSE. MADV_COLLAPSE on a range with a userfaultfd will now return EBUSY if there are any missing pages (instead of succeeding on shmem and returning EINVAL on anonymous memory). There is also now a window during MADV_COLLAPSE where a fault on a missing page will cause the syscall to fail with EAGAIN. The fact that intermediate page cache state can no longer be observed before the rollback of a failed collapse is also technically a userspace-visible change (via at least SEEK_DATA and SEEK_END), but it is exceedingly unlikely that anything relies on being able to observe that transient state. Link: https://lkml.kernel.org/r/20230404120117.2562166-4-stevensd@google.com Signed-off-by: David Stevens Acked-by: Peter Xu Cc: David Hildenbrand Cc: Hugh Dickins Cc: Jiaqi Yan Cc: "Kirill A. Shutemov" Cc: Matthew Wilcox (Oracle) Cc: Yang Shi Signed-off-by: Andrew Morton --- include/trace/events/huge_memory.h | 3 +- mm/khugepaged.c | 99 ++++++++++++++++++++++++++++++-------- 2 files changed, 81 insertions(+), 21 deletions(-) (limited to 'include') diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h index eca4c6f3625e..6e2ef1d4b002 100644 --- a/include/trace/events/huge_memory.h +++ b/include/trace/events/huge_memory.h @@ -38,7 +38,8 @@ EM( SCAN_TRUNCATED, "truncated") \ EM( SCAN_PAGE_HAS_PRIVATE, "page_has_private") \ EM( SCAN_STORE_FAILED, "store_failed") \ - EMe(SCAN_COPY_MC, "copy_poisoned_page") + EM( SCAN_COPY_MC, "copy_poisoned_page") \ + EMe(SCAN_PAGE_FILLED, "page_filled") #undef EM #undef EMe diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 762877539634..434674ca0c8a 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -57,6 +57,7 @@ enum scan_result { SCAN_PAGE_HAS_PRIVATE, SCAN_STORE_FAILED, SCAN_COPY_MC, + SCAN_PAGE_FILLED, }; #define CREATE_TRACE_POINTS @@ -1860,8 +1861,8 @@ next: * - allocate and lock a new huge page; * - scan page cache replacing old pages with the new one * + swap/gup in pages if necessary; - * + fill in gaps; * + keep old pages around in case rollback is required; + * - finalize updates to the page cache; * - if replacing succeeds: * + copy data over; * + free old pages; @@ -1939,7 +1940,7 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, result = SCAN_TRUNCATED; goto xa_locked; } - xas_set(&xas, index); + xas_set(&xas, index + 1); } if (!shmem_charge(mapping->host, 1)) { result = SCAN_FAIL; @@ -2176,22 +2177,66 @@ xa_unlocked: index++; } - /* - * Copying old pages to huge one has succeeded, now we - * need to free the old pages. - */ - list_for_each_entry_safe(page, tmp, &pagelist, lru) { - list_del(&page->lru); - page->mapping = NULL; - page_ref_unfreeze(page, 1); - ClearPageActive(page); - ClearPageUnevictable(page); - unlock_page(page); - put_page(page); + if (nr_none) { + struct vm_area_struct *vma; + int nr_none_check = 0; + + i_mmap_lock_read(mapping); + xas_lock_irq(&xas); + + xas_set(&xas, start); + for (index = start; index < end; index++) { + if (!xas_next(&xas)) { + xas_store(&xas, XA_RETRY_ENTRY); + if (xas_error(&xas)) { + result = SCAN_STORE_FAILED; + goto immap_locked; + } + nr_none_check++; + } + } + + if (nr_none != nr_none_check) { + result = SCAN_PAGE_FILLED; + goto immap_locked; + } + + /* + * If userspace observed a missing page in a VMA with a MODE_MISSING + * userfaultfd, then it might expect a UFFD_EVENT_PAGEFAULT for that + * page. If so, we need to roll back to avoid suppressing such an + * event. Since wp/minor userfaultfds don't give userspace any + * guarantees that the kernel doesn't fill a missing page with a zero + * page, so they don't matter here. + * + * Any userfaultfds registered after this point will not be able to + * observe any missing pages due to the previously inserted retry + * entries. + */ + vma_interval_tree_foreach(vma, &mapping->i_mmap, start, end) { + if (userfaultfd_missing(vma)) { + result = SCAN_EXCEED_NONE_PTE; + goto immap_locked; + } + } + +immap_locked: + i_mmap_unlock_read(mapping); + if (result != SCAN_SUCCEED) { + xas_set(&xas, start); + for (index = start; index < end; index++) { + if (xas_next(&xas) == XA_RETRY_ENTRY) + xas_store(&xas, NULL); + } + + xas_unlock_irq(&xas); + goto rollback; + } + } else { + xas_lock_irq(&xas); } nr = thp_nr_pages(hpage); - xas_lock_irq(&xas); if (is_shmem) __mod_lruvec_page_state(hpage, NR_SHMEM_THPS, nr); else @@ -2221,6 +2266,20 @@ xa_unlocked: result = retract_page_tables(mapping, start, mm, addr, hpage, cc); unlock_page(hpage); + + /* + * The collapse has succeeded, so free the old pages. + */ + list_for_each_entry_safe(page, tmp, &pagelist, lru) { + list_del(&page->lru); + page->mapping = NULL; + page_ref_unfreeze(page, 1); + ClearPageActive(page); + ClearPageUnevictable(page); + unlock_page(page); + put_page(page); + } + goto out; rollback: @@ -2232,15 +2291,13 @@ rollback: } xas_set(&xas, start); - xas_for_each(&xas, page, end - 1) { + end = index; + for (index = start; index < end; index++) { + xas_next(&xas); page = list_first_entry_or_null(&pagelist, struct page, lru); if (!page || xas.xa_index < page->index) { - if (!nr_none) - break; nr_none--; - /* Put holes back where they were */ - xas_store(&xas, NULL); continue; } @@ -2764,12 +2821,14 @@ static int madvise_collapse_errno(enum scan_result r) case SCAN_ALLOC_HUGE_PAGE_FAIL: return -ENOMEM; case SCAN_CGROUP_CHARGE_FAIL: + case SCAN_EXCEED_NONE_PTE: return -EBUSY; /* Resource temporary unavailable - trying again might succeed */ case SCAN_PAGE_COUNT: case SCAN_PAGE_LOCK: case SCAN_PAGE_LRU: case SCAN_DEL_PAGE_LRU: + case SCAN_PAGE_FILLED: return -EAGAIN; /* * Other: Trying again likely not to succeed / error intrinsic to -- cgit v1.2.3 From ddc65971bb677aa9f6a4c21f76d3133e106f88eb Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Tue, 4 Apr 2023 21:31:48 +0900 Subject: prctl: add PR_GET_AUXV to copy auxv to userspace If a library wants to get information from auxv (for instance, AT_HWCAP/AT_HWCAP2), it has a few options, none of them perfectly reliable or ideal: - Be main or the pre-main startup code, and grub through the stack above main. Doesn't work for a library. - Call libc getauxval. Not ideal for libraries that are trying to be libc-independent and/or don't otherwise require anything from other libraries. - Open and read /proc/self/auxv. Doesn't work for libraries that may run in arbitrarily constrained environments that may not have /proc mounted (e.g. libraries that might be used by an init program or a container setup tool). - Assume you're on the main thread and still on the original stack, and try to walk the stack upwards, hoping to find auxv. Extremely bad idea. - Ask the caller to pass auxv in for you. Not ideal for a user-friendly library, and then your caller may have the same problem. Add a prctl that copies current->mm->saved_auxv to a userspace buffer. Link: https://lkml.kernel.org/r/d81864a7f7f43bca6afa2a09fc2e850e4050ab42.1680611394.git.josh@joshtriplett.org Signed-off-by: Josh Triplett Signed-off-by: Andrew Morton --- include/uapi/linux/prctl.h | 2 ++ kernel/sys.c | 15 +++++++++++++++ 2 files changed, 17 insertions(+) (limited to 'include') diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 1312a137f7fb..b99c0be72577 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -290,4 +290,6 @@ struct prctl_mm_map { #define PR_SET_VMA 0x53564d41 # define PR_SET_VMA_ANON_NAME 0 +#define PR_GET_AUXV 0x41555856 + #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 351de7916302..26c1399e0654 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -2388,6 +2388,16 @@ static inline int prctl_get_mdwe(unsigned long arg2, unsigned long arg3, PR_MDWE_REFUSE_EXEC_GAIN : 0; } +static int prctl_get_auxv(void __user *addr, unsigned long len) +{ + struct mm_struct *mm = current->mm; + unsigned long size = min_t(unsigned long, sizeof(mm->saved_auxv), len); + + if (size && copy_to_user(addr, mm->saved_auxv, size)) + return -EFAULT; + return sizeof(mm->saved_auxv); +} + SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, unsigned long, arg4, unsigned long, arg5) { @@ -2518,6 +2528,11 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, else return -EINVAL; break; + case PR_GET_AUXV: + if (arg4 || arg5) + return -EINVAL; + error = prctl_get_auxv((void __user *)arg2, arg3); + break; default: return -EINVAL; } -- cgit v1.2.3 From b4aca54792e76556bb9f8661bab07b4bf2eb4e5f Mon Sep 17 00:00:00 2001 From: Steven Price Date: Wed, 5 Apr 2023 11:38:19 +0100 Subject: smaps: fix defined but not used smaps_shmem_walk_ops MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When !CONFIG_SHMEM smaps_shmem_walk_ops is defined but not used, triggering a compiler warning. To avoid the warning remove the #ifdef around the usage. This has no effect because shmem_mapping() is a stub returning false when !CONFIG_SHMEM so the code will be compiled out, however we now need to also provide a stub for shmem_swap_usage(). Link: https://lkml.kernel.org/r/20230405103819.151246-1-steven.price@arm.com Fixes: 7b86ac3371b7 ("pagewalk: separate function pointers from iterator data") Signed-off-by: Steven Price Reported-by: kernel test robot Link: https://lore.kernel.org/oe-kbuild-all/202304031749.UiyJpxzF-lkp@intel.com/ Reviewed-by: Jason Gunthorpe Cc: Christoph Hellwig Cc: Alexey Dobriyan Cc: Thomas Hellström Signed-off-by: Andrew Morton --- fs/proc/task_mmu.c | 3 +-- include/linux/shmem_fs.h | 7 +++++++ 2 files changed, 8 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 6a96e1713fd5..cb49479acd2e 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -782,7 +782,6 @@ static void smap_gather_stats(struct vm_area_struct *vma, if (start >= vma->vm_end) return; -#ifdef CONFIG_SHMEM if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { /* * For shared or readonly shmem mappings we know that all @@ -803,7 +802,7 @@ static void smap_gather_stats(struct vm_area_struct *vma, ops = &smaps_shmem_walk_ops; } } -#endif + /* mmap_lock is held in m_start */ if (!start) walk_page_vma(vma, ops, mss); diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index 3bb8d21edbb3..b9516a9802bf 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -96,7 +96,14 @@ int shmem_unuse(unsigned int type); extern bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force, struct mm_struct *mm, unsigned long vm_flags); +#ifdef CONFIG_SHMEM extern unsigned long shmem_swap_usage(struct vm_area_struct *vma); +#else +static inline unsigned long shmem_swap_usage(struct vm_area_struct *vma) +{ + return 0; +} +#endif extern unsigned long shmem_partial_swap_usage(struct address_space *mapping, pgoff_t start, pgoff_t end); -- cgit v1.2.3 From e87340ca5c9cecc8a11daf1a2dcabf23f06a4e10 Mon Sep 17 00:00:00 2001 From: ZhangPeng Date: Mon, 10 Apr 2023 21:39:29 +0800 Subject: userfaultfd: convert copy_huge_page_from_user() to copy_folio_from_user() Replace copy_huge_page_from_user() with copy_folio_from_user(). copy_folio_from_user() does the same as copy_huge_page_from_user(), but takes in a folio instead of a page. Convert page_kaddr to kaddr in copy_folio_from_user() to do indenting cleanup. Link: https://lkml.kernel.org/r/20230410133932.32288-4-zhangpeng362@huawei.com Signed-off-by: ZhangPeng Reviewed-by: Sidhartha Kumar Reviewed-by: Mike Kravetz Cc: Kefeng Wang Cc: Matthew Wilcox Cc: Muchun Song Cc: Nanyong Sun Cc: Vishal Moola (Oracle) Signed-off-by: Andrew Morton --- include/linux/mm.h | 7 +++---- mm/hugetlb.c | 5 ++--- mm/memory.c | 23 +++++++++++------------ mm/userfaultfd.c | 6 ++---- 4 files changed, 18 insertions(+), 23 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 5e5ef6ee4003..01a009efc2cb 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3681,10 +3681,9 @@ extern void copy_user_huge_page(struct page *dst, struct page *src, unsigned long addr_hint, struct vm_area_struct *vma, unsigned int pages_per_huge_page); -extern long copy_huge_page_from_user(struct page *dst_page, - const void __user *usr_src, - unsigned int pages_per_huge_page, - bool allow_pagefault); +long copy_folio_from_user(struct folio *dst_folio, + const void __user *usr_src, + bool allow_pagefault); /** * vma_is_special_huge - Are transhuge page-table entries considered special? diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 7e4a80769c9e..aade1b513474 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6217,9 +6217,8 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, goto out; } - ret = copy_huge_page_from_user(&folio->page, - (const void __user *) src_addr, - pages_per_huge_page(h), false); + ret = copy_folio_from_user(folio, (const void __user *) src_addr, + false); /* fallback to copy_from_user outside mmap_lock */ if (unlikely(ret)) { diff --git a/mm/memory.c b/mm/memory.c index 808f354bce65..021cab989703 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5868,26 +5868,25 @@ void copy_user_huge_page(struct page *dst, struct page *src, process_huge_page(addr_hint, pages_per_huge_page, copy_subpage, &arg); } -long copy_huge_page_from_user(struct page *dst_page, - const void __user *usr_src, - unsigned int pages_per_huge_page, - bool allow_pagefault) +long copy_folio_from_user(struct folio *dst_folio, + const void __user *usr_src, + bool allow_pagefault) { - void *page_kaddr; + void *kaddr; unsigned long i, rc = 0; - unsigned long ret_val = pages_per_huge_page * PAGE_SIZE; + unsigned int nr_pages = folio_nr_pages(dst_folio); + unsigned long ret_val = nr_pages * PAGE_SIZE; struct page *subpage; - for (i = 0; i < pages_per_huge_page; i++) { - subpage = nth_page(dst_page, i); - page_kaddr = kmap_local_page(subpage); + for (i = 0; i < nr_pages; i++) { + subpage = folio_page(dst_folio, i); + kaddr = kmap_local_page(subpage); if (!allow_pagefault) pagefault_disable(); - rc = copy_from_user(page_kaddr, - usr_src + i * PAGE_SIZE, PAGE_SIZE); + rc = copy_from_user(kaddr, usr_src + i * PAGE_SIZE, PAGE_SIZE); if (!allow_pagefault) pagefault_enable(); - kunmap_local(page_kaddr); + kunmap_local(kaddr); ret_val -= (PAGE_SIZE - rc); if (rc) diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 313bc683c2b6..1e7dba6c4c5f 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -421,10 +421,8 @@ retry: mmap_read_unlock(dst_mm); BUG_ON(!page); - err = copy_huge_page_from_user(page, - (const void __user *)src_addr, - vma_hpagesize / PAGE_SIZE, - true); + err = copy_folio_from_user(page_folio(page), + (const void __user *)src_addr, true); if (unlikely(err)) { err = -EFAULT; goto out; -- cgit v1.2.3 From 0169fd518a8934d8d723659752b07589ecc9f692 Mon Sep 17 00:00:00 2001 From: ZhangPeng Date: Mon, 10 Apr 2023 21:39:30 +0800 Subject: userfaultfd: convert mfill_atomic_hugetlb() to use a folio Convert hugetlb_mfill_atomic_pte() to take in a folio pointer instead of a page pointer. Convert mfill_atomic_hugetlb() to use a folio. Link: https://lkml.kernel.org/r/20230410133932.32288-5-zhangpeng362@huawei.com Signed-off-by: ZhangPeng Reviewed-by: Sidhartha Kumar Reviewed-by: Mike Kravetz Cc: Kefeng Wang Cc: Matthew Wilcox Cc: Muchun Song Cc: Nanyong Sun Cc: Vishal Moola (Oracle) Signed-off-by: Andrew Morton --- include/linux/hugetlb.h | 4 ++-- mm/hugetlb.c | 26 +++++++++++++------------- mm/userfaultfd.c | 16 ++++++++-------- 3 files changed, 23 insertions(+), 23 deletions(-) (limited to 'include') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 2a758bcd6719..28703fe22386 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -163,7 +163,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, unsigned long dst_addr, unsigned long src_addr, uffd_flags_t flags, - struct page **pagep); + struct folio **foliop); #endif /* CONFIG_USERFAULTFD */ bool hugetlb_reserve_pages(struct inode *inode, long from, long to, struct vm_area_struct *vma, @@ -397,7 +397,7 @@ static inline int hugetlb_mfill_atomic_pte(pte_t *dst_pte, unsigned long dst_addr, unsigned long src_addr, uffd_flags_t flags, - struct page **pagep) + struct folio **foliop) { BUG(); return 0; diff --git a/mm/hugetlb.c b/mm/hugetlb.c index aade1b513474..c88f856ec2e2 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6178,7 +6178,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, unsigned long dst_addr, unsigned long src_addr, uffd_flags_t flags, - struct page **pagep) + struct folio **foliop) { struct mm_struct *dst_mm = dst_vma->vm_mm; bool is_continue = uffd_flags_mode_is(flags, MFILL_ATOMIC_CONTINUE); @@ -6201,8 +6201,8 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, if (IS_ERR(folio)) goto out; folio_in_pagecache = true; - } else if (!*pagep) { - /* If a page already exists, then it's UFFDIO_COPY for + } else if (!*foliop) { + /* If a folio already exists, then it's UFFDIO_COPY for * a non-missing case. Return -EEXIST. */ if (vm_shared && @@ -6237,33 +6237,33 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, ret = -ENOMEM; goto out; } - *pagep = &folio->page; - /* Set the outparam pagep and return to the caller to + *foliop = folio; + /* Set the outparam foliop and return to the caller to * copy the contents outside the lock. Don't free the - * page. + * folio. */ goto out; } } else { if (vm_shared && hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { - put_page(*pagep); + folio_put(*foliop); ret = -EEXIST; - *pagep = NULL; + *foliop = NULL; goto out; } folio = alloc_hugetlb_folio(dst_vma, dst_addr, 0); if (IS_ERR(folio)) { - put_page(*pagep); + folio_put(*foliop); ret = -ENOMEM; - *pagep = NULL; + *foliop = NULL; goto out; } - copy_user_huge_page(&folio->page, *pagep, dst_addr, dst_vma, + copy_user_huge_page(&folio->page, &(*foliop)->page, dst_addr, dst_vma, pages_per_huge_page(h)); - put_page(*pagep); - *pagep = NULL; + folio_put(*foliop); + *foliop = NULL; } /* diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 1e7dba6c4c5f..2f263afb823d 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -321,7 +321,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb( pte_t *dst_pte; unsigned long src_addr, dst_addr; long copied; - struct page *page; + struct folio *folio; unsigned long vma_hpagesize; pgoff_t idx; u32 hash; @@ -341,7 +341,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb( src_addr = src_start; dst_addr = dst_start; copied = 0; - page = NULL; + folio = NULL; vma_hpagesize = vma_kernel_pagesize(dst_vma); /* @@ -410,7 +410,7 @@ retry: } err = hugetlb_mfill_atomic_pte(dst_pte, dst_vma, dst_addr, - src_addr, flags, &page); + src_addr, flags, &folio); hugetlb_vma_unlock_read(dst_vma); mutex_unlock(&hugetlb_fault_mutex_table[hash]); @@ -419,9 +419,9 @@ retry: if (unlikely(err == -ENOENT)) { mmap_read_unlock(dst_mm); - BUG_ON(!page); + BUG_ON(!folio); - err = copy_folio_from_user(page_folio(page), + err = copy_folio_from_user(folio, (const void __user *)src_addr, true); if (unlikely(err)) { err = -EFAULT; @@ -432,7 +432,7 @@ retry: dst_vma = NULL; goto retry; } else - BUG_ON(page); + BUG_ON(folio); if (!err) { dst_addr += vma_hpagesize; @@ -449,8 +449,8 @@ retry: out_unlock: mmap_read_unlock(dst_mm); out: - if (page) - put_page(page); + if (folio) + folio_put(folio); BUG_ON(copied < 0); BUG_ON(err > 0); BUG_ON(!copied && !err); -- cgit v1.2.3 From c0e8150e144b62ae467520d0b51c4707c09e897b Mon Sep 17 00:00:00 2001 From: ZhangPeng Date: Mon, 10 Apr 2023 21:39:31 +0800 Subject: mm: convert copy_user_huge_page() to copy_user_large_folio() Replace copy_user_huge_page() with copy_user_large_folio(). copy_user_large_folio() does the same as copy_user_huge_page(), but takes in folios instead of pages. Remove pages_per_huge_page from copy_user_large_folio(), because we can get that from folio_nr_pages(dst). Convert copy_user_gigantic_page() to take in folios. Link: https://lkml.kernel.org/r/20230410133932.32288-6-zhangpeng362@huawei.com Signed-off-by: ZhangPeng Cc: Kefeng Wang Cc: Matthew Wilcox Cc: Mike Kravetz Cc: Muchun Song Cc: Nanyong Sun Cc: Sidhartha Kumar Cc: Vishal Moola (Oracle) Signed-off-by: Andrew Morton --- include/linux/mm.h | 7 +++---- mm/hugetlb.c | 11 +++++------ mm/memory.c | 28 ++++++++++++++-------------- 3 files changed, 22 insertions(+), 24 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 01a009efc2cb..5a3eaa9a1f8c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3677,10 +3677,9 @@ extern const struct attribute_group memory_failure_attr_group; extern void clear_huge_page(struct page *page, unsigned long addr_hint, unsigned int pages_per_huge_page); -extern void copy_user_huge_page(struct page *dst, struct page *src, - unsigned long addr_hint, - struct vm_area_struct *vma, - unsigned int pages_per_huge_page); +void copy_user_large_folio(struct folio *dst, struct folio *src, + unsigned long addr_hint, + struct vm_area_struct *vma); long copy_folio_from_user(struct folio *dst_folio, const void __user *usr_src, bool allow_pagefault); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index c88f856ec2e2..f16b25b1a6b9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5097,8 +5097,9 @@ again: ret = PTR_ERR(new_folio); break; } - copy_user_huge_page(&new_folio->page, ptepage, addr, dst_vma, - npages); + copy_user_large_folio(new_folio, + page_folio(ptepage), + addr, dst_vma); put_page(ptepage); /* Install the new hugetlb folio if src pte stable */ @@ -5616,8 +5617,7 @@ retry_avoidcopy: goto out_release_all; } - copy_user_huge_page(&new_folio->page, old_page, address, vma, - pages_per_huge_page(h)); + copy_user_large_folio(new_folio, page_folio(old_page), address, vma); __folio_mark_uptodate(new_folio); mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, haddr, @@ -6260,8 +6260,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, *foliop = NULL; goto out; } - copy_user_huge_page(&folio->page, &(*foliop)->page, dst_addr, dst_vma, - pages_per_huge_page(h)); + copy_user_large_folio(folio, *foliop, dst_addr, dst_vma); folio_put(*foliop); *foliop = NULL; } diff --git a/mm/memory.c b/mm/memory.c index 021cab989703..f315c2198098 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5815,21 +5815,21 @@ void clear_huge_page(struct page *page, process_huge_page(addr_hint, pages_per_huge_page, clear_subpage, page); } -static void copy_user_gigantic_page(struct page *dst, struct page *src, - unsigned long addr, - struct vm_area_struct *vma, - unsigned int pages_per_huge_page) +static void copy_user_gigantic_page(struct folio *dst, struct folio *src, + unsigned long addr, + struct vm_area_struct *vma, + unsigned int pages_per_huge_page) { int i; - struct page *dst_base = dst; - struct page *src_base = src; + struct page *dst_page; + struct page *src_page; for (i = 0; i < pages_per_huge_page; i++) { - dst = nth_page(dst_base, i); - src = nth_page(src_base, i); + dst_page = folio_page(dst, i); + src_page = folio_page(src, i); cond_resched(); - copy_user_highpage(dst, src, addr + i*PAGE_SIZE, vma); + copy_user_highpage(dst_page, src_page, addr + i*PAGE_SIZE, vma); } } @@ -5847,15 +5847,15 @@ static void copy_subpage(unsigned long addr, int idx, void *arg) addr, copy_arg->vma); } -void copy_user_huge_page(struct page *dst, struct page *src, - unsigned long addr_hint, struct vm_area_struct *vma, - unsigned int pages_per_huge_page) +void copy_user_large_folio(struct folio *dst, struct folio *src, + unsigned long addr_hint, struct vm_area_struct *vma) { + unsigned int pages_per_huge_page = folio_nr_pages(dst); unsigned long addr = addr_hint & ~(((unsigned long)pages_per_huge_page << PAGE_SHIFT) - 1); struct copy_subpage_arg arg = { - .dst = dst, - .src = src, + .dst = &dst->page, + .src = &src->page, .vma = vma, }; -- cgit v1.2.3 From d7be6d7eee1bbf98671d7a2c95654322241e2ae4 Mon Sep 17 00:00:00 2001 From: ZhangPeng Date: Mon, 10 Apr 2023 21:39:32 +0800 Subject: userfaultfd: convert mfill_atomic() to use a folio Convert mfill_atomic_pte_copy(), shmem_mfill_atomic_pte() and mfill_atomic_pte() to take in a folio pointer. Convert mfill_atomic() to use a folio. Convert page_kaddr to kaddr in mfill_atomic(). Link: https://lkml.kernel.org/r/20230410133932.32288-7-zhangpeng362@huawei.com Signed-off-by: ZhangPeng Reviewed-by: Mike Kravetz Cc: Kefeng Wang Cc: Matthew Wilcox Cc: Muchun Song Cc: Nanyong Sun Cc: Sidhartha Kumar Cc: Vishal Moola (Oracle) Signed-off-by: Andrew Morton --- include/linux/shmem_fs.h | 4 ++-- mm/shmem.c | 16 ++++++++-------- mm/userfaultfd.c | 40 ++++++++++++++++++++-------------------- 3 files changed, 30 insertions(+), 30 deletions(-) (limited to 'include') diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index b9516a9802bf..9029abd29b1c 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -165,10 +165,10 @@ extern int shmem_mfill_atomic_pte(pmd_t *dst_pmd, unsigned long dst_addr, unsigned long src_addr, uffd_flags_t flags, - struct page **pagep); + struct folio **foliop); #else /* !CONFIG_SHMEM */ #define shmem_mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, \ - src_addr, flags, pagep) ({ BUG(); 0; }) + src_addr, flags, foliop) ({ BUG(); 0; }) #endif /* CONFIG_SHMEM */ #endif /* CONFIG_USERFAULTFD */ diff --git a/mm/shmem.c b/mm/shmem.c index b185c1db3009..3531ebb3494e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2433,7 +2433,7 @@ int shmem_mfill_atomic_pte(pmd_t *dst_pmd, unsigned long dst_addr, unsigned long src_addr, uffd_flags_t flags, - struct page **pagep) + struct folio **foliop) { struct inode *inode = file_inode(dst_vma->vm_file); struct shmem_inode_info *info = SHMEM_I(inode); @@ -2451,14 +2451,14 @@ int shmem_mfill_atomic_pte(pmd_t *dst_pmd, * and now we find ourselves with -ENOMEM. Release the page, to * avoid a BUG_ON in our caller. */ - if (unlikely(*pagep)) { - put_page(*pagep); - *pagep = NULL; + if (unlikely(*foliop)) { + folio_put(*foliop); + *foliop = NULL; } return -ENOMEM; } - if (!*pagep) { + if (!*foliop) { ret = -ENOMEM; folio = shmem_alloc_folio(gfp, info, pgoff); if (!folio) @@ -2490,7 +2490,7 @@ int shmem_mfill_atomic_pte(pmd_t *dst_pmd, /* fallback to copy_from_user outside mmap_lock */ if (unlikely(ret)) { - *pagep = &folio->page; + *foliop = folio; ret = -ENOENT; /* don't free the page */ goto out_unacct_blocks; @@ -2501,9 +2501,9 @@ int shmem_mfill_atomic_pte(pmd_t *dst_pmd, clear_user_highpage(&folio->page, dst_addr); } } else { - folio = page_folio(*pagep); + folio = *foliop; VM_BUG_ON_FOLIO(folio_test_large(folio), folio); - *pagep = NULL; + *foliop = NULL; } VM_BUG_ON(folio_test_locked(folio)); diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 2f263afb823d..11cfd82c6726 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -133,13 +133,13 @@ static int mfill_atomic_pte_copy(pmd_t *dst_pmd, unsigned long dst_addr, unsigned long src_addr, uffd_flags_t flags, - struct page **pagep) + struct folio **foliop) { void *kaddr; int ret; struct folio *folio; - if (!*pagep) { + if (!*foliop) { ret = -ENOMEM; folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, dst_vma, dst_addr, false); @@ -171,15 +171,15 @@ static int mfill_atomic_pte_copy(pmd_t *dst_pmd, /* fallback to copy_from_user outside mmap_lock */ if (unlikely(ret)) { ret = -ENOENT; - *pagep = &folio->page; + *foliop = folio; /* don't free the page */ goto out; } flush_dcache_folio(folio); } else { - folio = page_folio(*pagep); - *pagep = NULL; + folio = *foliop; + *foliop = NULL; } /* @@ -470,7 +470,7 @@ static __always_inline ssize_t mfill_atomic_pte(pmd_t *dst_pmd, unsigned long dst_addr, unsigned long src_addr, uffd_flags_t flags, - struct page **pagep) + struct folio **foliop) { ssize_t err; @@ -493,14 +493,14 @@ static __always_inline ssize_t mfill_atomic_pte(pmd_t *dst_pmd, if (uffd_flags_mode_is(flags, MFILL_ATOMIC_COPY)) err = mfill_atomic_pte_copy(dst_pmd, dst_vma, dst_addr, src_addr, - flags, pagep); + flags, foliop); else err = mfill_atomic_pte_zeropage(dst_pmd, dst_vma, dst_addr); } else { err = shmem_mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, src_addr, - flags, pagep); + flags, foliop); } return err; @@ -518,7 +518,7 @@ static __always_inline ssize_t mfill_atomic(struct mm_struct *dst_mm, pmd_t *dst_pmd; unsigned long src_addr, dst_addr; long copied; - struct page *page; + struct folio *folio; /* * Sanitize the command parameters: @@ -533,7 +533,7 @@ static __always_inline ssize_t mfill_atomic(struct mm_struct *dst_mm, src_addr = src_start; dst_addr = dst_start; copied = 0; - page = NULL; + folio = NULL; retry: mmap_read_lock(dst_mm); @@ -629,28 +629,28 @@ retry: BUG_ON(pmd_trans_huge(*dst_pmd)); err = mfill_atomic_pte(dst_pmd, dst_vma, dst_addr, - src_addr, flags, &page); + src_addr, flags, &folio); cond_resched(); if (unlikely(err == -ENOENT)) { - void *page_kaddr; + void *kaddr; mmap_read_unlock(dst_mm); - BUG_ON(!page); + BUG_ON(!folio); - page_kaddr = kmap_local_page(page); - err = copy_from_user(page_kaddr, + kaddr = kmap_local_folio(folio, 0); + err = copy_from_user(kaddr, (const void __user *) src_addr, PAGE_SIZE); - kunmap_local(page_kaddr); + kunmap_local(kaddr); if (unlikely(err)) { err = -EFAULT; goto out; } - flush_dcache_page(page); + flush_dcache_folio(folio); goto retry; } else - BUG_ON(page); + BUG_ON(folio); if (!err) { dst_addr += PAGE_SIZE; @@ -667,8 +667,8 @@ retry: out_unlock: mmap_read_unlock(dst_mm); out: - if (page) - put_page(page); + if (folio) + folio_put(folio); BUG_ON(copied < 0); BUG_ON(err > 0); BUG_ON(!copied && !err); -- cgit v1.2.3 From 87a7ae75d7383afa998f57656d1d14e2a730cc47 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Tue, 11 Apr 2023 19:52:13 +0530 Subject: mm/vmemmap/devdax: fix kernel crash when probing devdax devices commit 4917f55b4ef9 ("mm/sparse-vmemmap: improve memory savings for compound devmaps") added support for using optimized vmmemap for devdax devices. But how vmemmap mappings are created are architecture specific. For example, powerpc with hash translation doesn't have vmemmap mappings in init_mm page table instead they are bolted table entries in the hardware page table vmemmap_populate_compound_pages() used by vmemmap optimization code is not aware of these architecture-specific mapping. Hence allow architecture to opt for this feature. I selected architectures supporting HUGETLB_PAGE_OPTIMIZE_VMEMMAP option as also supporting this feature. This patch fixes the below crash on ppc64. BUG: Unable to handle kernel data access on write at 0xc00c000100400038 Faulting instruction address: 0xc000000001269d90 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.3.0-rc5-150500.34-default+ #2 5c90a668b6bbd142599890245c2fb5de19d7d28a Hardware name: IBM,9009-42G POWER9 (raw) 0x4e0202 0xf000005 of:IBM,FW950.40 (VL950_099) hv:phyp pSeries NIP: c000000001269d90 LR: c0000000004c57d4 CTR: 0000000000000000 REGS: c000000003632c30 TRAP: 0300 Not tainted (6.3.0-rc5-150500.34-default+) MSR: 8000000000009033 CR: 24842228 XER: 00000000 CFAR: c0000000004c57d0 DAR: c00c000100400038 DSISR: 42000000 IRQMASK: 0 .... NIP [c000000001269d90] __init_single_page.isra.74+0x14/0x4c LR [c0000000004c57d4] __init_zone_device_page+0x44/0xd0 Call Trace: [c000000003632ed0] [c000000003632f60] 0xc000000003632f60 (unreliable) [c000000003632f10] [c0000000004c5ca0] memmap_init_zone_device+0x170/0x250 [c000000003632fe0] [c0000000005575f8] memremap_pages+0x2c8/0x7f0 [c0000000036330c0] [c000000000557b5c] devm_memremap_pages+0x3c/0xa0 [c000000003633100] [c000000000d458a8] dev_dax_probe+0x108/0x3e0 [c0000000036331a0] [c000000000d41430] dax_bus_probe+0xb0/0x140 [c0000000036331d0] [c000000000cef27c] really_probe+0x19c/0x520 [c000000003633260] [c000000000cef6b4] __driver_probe_device+0xb4/0x230 [c0000000036332e0] [c000000000cef888] driver_probe_device+0x58/0x120 [c000000003633320] [c000000000cefa6c] __device_attach_driver+0x11c/0x1e0 [c0000000036333a0] [c000000000cebc58] bus_for_each_drv+0xa8/0x130 [c000000003633400] [c000000000ceefcc] __device_attach+0x15c/0x250 [c0000000036334a0] [c000000000ced458] bus_probe_device+0x108/0x110 [c0000000036334f0] [c000000000ce92dc] device_add+0x7fc/0xa10 [c0000000036335b0] [c000000000d447c8] devm_create_dev_dax+0x1d8/0x530 [c000000003633640] [c000000000d46b60] __dax_pmem_probe+0x200/0x270 [c0000000036337b0] [c000000000d46bf0] dax_pmem_probe+0x20/0x70 [c0000000036337d0] [c000000000d2279c] nvdimm_bus_probe+0xac/0x2b0 [c000000003633860] [c000000000cef27c] really_probe+0x19c/0x520 [c0000000036338f0] [c000000000cef6b4] __driver_probe_device+0xb4/0x230 [c000000003633970] [c000000000cef888] driver_probe_device+0x58/0x120 [c0000000036339b0] [c000000000cefd08] __driver_attach+0x1d8/0x240 [c000000003633a30] [c000000000cebb04] bus_for_each_dev+0xb4/0x130 [c000000003633a90] [c000000000cee564] driver_attach+0x34/0x50 [c000000003633ab0] [c000000000ced878] bus_add_driver+0x218/0x300 [c000000003633b40] [c000000000cf1144] driver_register+0xa4/0x1b0 [c000000003633bb0] [c000000000d21a0c] __nd_driver_register+0x5c/0x100 [c000000003633c10] [c00000000206a2e8] dax_pmem_init+0x34/0x48 [c000000003633c30] [c0000000000132d0] do_one_initcall+0x60/0x320 [c000000003633d00] [c0000000020051b0] kernel_init_freeable+0x360/0x400 [c000000003633de0] [c000000000013764] kernel_init+0x34/0x1d0 [c000000003633e50] [c00000000000de14] ret_from_kernel_thread+0x5c/0x64 Link: https://lkml.kernel.org/r/20230411142214.64464-1-aneesh.kumar@linux.ibm.com Fixes: 4917f55b4ef9 ("mm/sparse-vmemmap: improve memory savings for compound devmaps") Signed-off-by: Aneesh Kumar K.V Reported-by: Tarun Sahu Reviewed-by: Joao Martins Cc: Muchun Song Cc: Dan Williams Cc: Mike Kravetz Cc: Signed-off-by: Andrew Morton --- include/linux/mm.h | 16 ++++++++++++++++ mm/mm_init.c | 10 ++++++---- mm/sparse-vmemmap.c | 3 +-- 3 files changed, 23 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 5a3eaa9a1f8c..21a7e2460084 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3560,6 +3560,22 @@ void vmemmap_populate_print_last(void); void vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap); #endif + +#ifdef CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP +static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap, + struct dev_pagemap *pgmap) +{ + return is_power_of_2(sizeof(struct page)) && + pgmap && (pgmap_vmemmap_nr(pgmap) > 1) && !altmap; +} +#else +static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap, + struct dev_pagemap *pgmap) +{ + return false; +} +#endif + void register_page_bootmem_memmap(unsigned long section_nr, struct page *map, unsigned long nr_pages); diff --git a/mm/mm_init.c b/mm/mm_init.c index a0ec3b3acb5e..7f7f9c677854 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -1015,10 +1015,12 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, * of an altmap. See vmemmap_populate_compound_pages(). */ static inline unsigned long compound_nr_pages(struct vmem_altmap *altmap, - unsigned long nr_pages) + struct dev_pagemap *pgmap) { - return is_power_of_2(sizeof(struct page)) && - !altmap ? 2 * (PAGE_SIZE / sizeof(struct page)) : nr_pages; + if (!vmemmap_can_optimize(altmap, pgmap)) + return pgmap_vmemmap_nr(pgmap); + + return 2 * (PAGE_SIZE / sizeof(struct page)); } static void __ref memmap_init_compound(struct page *head, @@ -1083,7 +1085,7 @@ void __ref memmap_init_zone_device(struct zone *zone, continue; memmap_init_compound(page, pfn, zone_idx, nid, pgmap, - compound_nr_pages(altmap, pfns_per_compound)); + compound_nr_pages(altmap, pgmap)); } pr_debug("%s initialised %lu pages in %ums\n", __func__, diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c index c5398a5960d0..10d73a0dfcec 100644 --- a/mm/sparse-vmemmap.c +++ b/mm/sparse-vmemmap.c @@ -458,8 +458,7 @@ struct page * __meminit __populate_section_memmap(unsigned long pfn, !IS_ALIGNED(nr_pages, PAGES_PER_SUBSECTION))) return NULL; - if (is_power_of_2(sizeof(struct page)) && - pgmap && pgmap_vmemmap_nr(pgmap) > 1 && !altmap) + if (vmemmap_can_optimize(altmap, pgmap)) r = vmemmap_populate_compound_pages(pfn, start, end, nid, pgmap); else r = vmemmap_populate(start, end, nid, altmap); -- cgit v1.2.3 From 0b376f1e0ff555435597fa16823ae0f30b2883e3 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 12 Apr 2023 10:30:25 +0530 Subject: mm/hugetlb_vmemmap: rename ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP Now we use ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP config option to indicate devdax and hugetlb vmemmap optimization support. Hence rename that to a generic ARCH_WANT_OPTIMIZE_VMEMMAP Link: https://lkml.kernel.org/r/20230412050025.84346-2-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V Reviewed-by: Muchun Song Cc: Joao Martins Cc: Dan Williams Cc: Mike Kravetz Cc: Tarun Sahu Signed-off-by: Andrew Morton --- arch/loongarch/Kconfig | 2 +- arch/s390/Kconfig | 2 +- arch/x86/Kconfig | 2 +- fs/Kconfig | 9 +-------- include/linux/mm.h | 2 +- mm/Kconfig | 6 ++++++ 6 files changed, 11 insertions(+), 12 deletions(-) (limited to 'include') diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index e1e3a3828962..5abd13093c1a 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -53,8 +53,8 @@ config LOONGARCH select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT - select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP select ARCH_WANT_LD_ORPHAN_WARN + select ARCH_WANT_OPTIMIZE_VMEMMAP select ARCH_WANTS_NO_INSTR select BUILDTIME_TABLE_SORT select COMMON_CLK diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 548b5b587003..61d778397720 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -126,8 +126,8 @@ config S390 select ARCH_WANTS_DYNAMIC_TASK_STRUCT select ARCH_WANTS_NO_INSTR select ARCH_WANT_DEFAULT_BPF_JIT - select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP select ARCH_WANT_IPC_PARSE_VERSION + select ARCH_WANT_OPTIMIZE_VMEMMAP select BUILDTIME_TABLE_SORT select CLONE_BACKWARDS2 select DMA_OPS if PCI diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index df21fba77db1..4c123315c440 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -126,8 +126,8 @@ config X86 select ARCH_WANTS_NO_INSTR select ARCH_WANT_GENERAL_HUGETLB select ARCH_WANT_HUGE_PMD_SHARE - select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP if X86_64 select ARCH_WANT_LD_ORPHAN_WARN + select ARCH_WANT_OPTIMIZE_VMEMMAP if X86_64 select ARCH_WANTS_THP_SWAP if X86_64 select ARCH_HAS_PARANOID_L1D_FLUSH select BUILDTIME_TABLE_SORT diff --git a/fs/Kconfig b/fs/Kconfig index e99830c65033..cc07a0cd3172 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -250,16 +250,9 @@ config HUGETLBFS config HUGETLB_PAGE def_bool HUGETLBFS -# -# Select this config option from the architecture Kconfig, if it is preferred -# to enable the feature of HugeTLB Vmemmap Optimization (HVO). -# -config ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP - bool - config HUGETLB_PAGE_OPTIMIZE_VMEMMAP def_bool HUGETLB_PAGE - depends on ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP + depends on ARCH_WANT_OPTIMIZE_VMEMMAP depends on SPARSEMEM_VMEMMAP config HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON diff --git a/include/linux/mm.h b/include/linux/mm.h index 21a7e2460084..0b514de43143 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3561,7 +3561,7 @@ void vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap); #endif -#ifdef CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP +#ifdef CONFIG_ARCH_WANT_OPTIMIZE_VMEMMAP static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap, struct dev_pagemap *pgmap) { diff --git a/mm/Kconfig b/mm/Kconfig index 6ee3b48ed298..5ca8fcfae243 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -479,6 +479,12 @@ config SPARSEMEM_VMEMMAP SPARSEMEM_VMEMMAP uses a virtually mapped memmap to optimise pfn_to_page and page_to_pfn operations. This is the most efficient option when sufficient kernel resources are available. +# +# Select this config option from the architecture Kconfig, if it is preferred +# to enable the feature of HugeTLB/dev_dax vmemmap optimization. +# +config ARCH_WANT_OPTIMIZE_VMEMMAP + bool config HAVE_MEMBLOCK_PHYS_MAP bool -- cgit v1.2.3 From 1cb9dc4b475c7418f925ab0c97b6750007d9f52e Mon Sep 17 00:00:00 2001 From: Liu Shixin Date: Thu, 13 Apr 2023 21:13:49 +0800 Subject: mm: hwpoison: support recovery from HugePage copy-on-write faults copy-on-write of hugetlb user pages with uncorrectable errors will result in a kernel crash. This is because the copy is performed in kernel mode and in general we can not handle accessing memory with such errors while in kernel mode. Commit a873dfe1032a ("mm, hwpoison: try to recover from copy-on write faults") introduced the routine copy_user_highpage_mc() to gracefully handle copying of user pages with uncorrectable errors. However, the separate hugetlb copy-on-write code paths were not modified as part of commit a873dfe1032a. Modify hugetlb copy-on-write code paths to use copy_mc_user_highpage() so that they can also gracefully handle uncorrectable errors in user pages. This involves changing the hugetlb specific routine copy_user_large_folio() from type void to int so that it can return an error. Modify the hugetlb userfaultfd code in the same way so that it can return -EHWPOISON if it encounters an uncorrectable error. Link: https://lkml.kernel.org/r/20230413131349.2524210-1-liushixin2@huawei.com Signed-off-by: Liu Shixin Acked-by: Mike Kravetz Reviewed-by: Naoya Horiguchi Cc: Miaohe Lin Cc: Muchun Song Cc: Tony Luck Signed-off-by: Andrew Morton --- include/linux/mm.h | 6 +++--- mm/hugetlb.c | 17 +++++++++++++--- mm/memory.c | 59 +++++++++++++++++++++++++++++++++++------------------- 3 files changed, 55 insertions(+), 27 deletions(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 0b514de43143..2772a1800cf3 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3693,9 +3693,9 @@ extern const struct attribute_group memory_failure_attr_group; extern void clear_huge_page(struct page *page, unsigned long addr_hint, unsigned int pages_per_huge_page); -void copy_user_large_folio(struct folio *dst, struct folio *src, - unsigned long addr_hint, - struct vm_area_struct *vma); +int copy_user_large_folio(struct folio *dst, struct folio *src, + unsigned long addr_hint, + struct vm_area_struct *vma); long copy_folio_from_user(struct folio *dst_folio, const void __user *usr_src, bool allow_pagefault); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f16b25b1a6b9..a08fb47fb200 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5097,10 +5097,14 @@ again: ret = PTR_ERR(new_folio); break; } - copy_user_large_folio(new_folio, + ret = copy_user_large_folio(new_folio, page_folio(ptepage), addr, dst_vma); put_page(ptepage); + if (ret) { + folio_put(new_folio); + break; + } /* Install the new hugetlb folio if src pte stable */ dst_ptl = huge_pte_lock(h, dst, dst_pte); @@ -5617,7 +5621,10 @@ retry_avoidcopy: goto out_release_all; } - copy_user_large_folio(new_folio, page_folio(old_page), address, vma); + if (copy_user_large_folio(new_folio, page_folio(old_page), address, vma)) { + ret = VM_FAULT_HWPOISON_LARGE; + goto out_release_all; + } __folio_mark_uptodate(new_folio); mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, haddr, @@ -6260,9 +6267,13 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, *foliop = NULL; goto out; } - copy_user_large_folio(folio, *foliop, dst_addr, dst_vma); + ret = copy_user_large_folio(folio, *foliop, dst_addr, dst_vma); folio_put(*foliop); *foliop = NULL; + if (ret) { + folio_put(folio); + goto out; + } } /* diff --git a/mm/memory.c b/mm/memory.c index f315c2198098..f7510a06a2d0 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5733,12 +5733,12 @@ EXPORT_SYMBOL(__might_fault); * operation. The target subpage will be processed last to keep its * cache lines hot. */ -static inline void process_huge_page( +static inline int process_huge_page( unsigned long addr_hint, unsigned int pages_per_huge_page, - void (*process_subpage)(unsigned long addr, int idx, void *arg), + int (*process_subpage)(unsigned long addr, int idx, void *arg), void *arg) { - int i, n, base, l; + int i, n, base, l, ret; unsigned long addr = addr_hint & ~(((unsigned long)pages_per_huge_page << PAGE_SHIFT) - 1); @@ -5752,7 +5752,9 @@ static inline void process_huge_page( /* Process subpages at the end of huge page */ for (i = pages_per_huge_page - 1; i >= 2 * n; i--) { cond_resched(); - process_subpage(addr + i * PAGE_SIZE, i, arg); + ret = process_subpage(addr + i * PAGE_SIZE, i, arg); + if (ret) + return ret; } } else { /* If target subpage in second half of huge page */ @@ -5761,7 +5763,9 @@ static inline void process_huge_page( /* Process subpages at the begin of huge page */ for (i = 0; i < base; i++) { cond_resched(); - process_subpage(addr + i * PAGE_SIZE, i, arg); + ret = process_subpage(addr + i * PAGE_SIZE, i, arg); + if (ret) + return ret; } } /* @@ -5773,10 +5777,15 @@ static inline void process_huge_page( int right_idx = base + 2 * l - 1 - i; cond_resched(); - process_subpage(addr + left_idx * PAGE_SIZE, left_idx, arg); + ret = process_subpage(addr + left_idx * PAGE_SIZE, left_idx, arg); + if (ret) + return ret; cond_resched(); - process_subpage(addr + right_idx * PAGE_SIZE, right_idx, arg); + ret = process_subpage(addr + right_idx * PAGE_SIZE, right_idx, arg); + if (ret) + return ret; } + return 0; } static void clear_gigantic_page(struct page *page, @@ -5794,11 +5803,12 @@ static void clear_gigantic_page(struct page *page, } } -static void clear_subpage(unsigned long addr, int idx, void *arg) +static int clear_subpage(unsigned long addr, int idx, void *arg) { struct page *page = arg; clear_user_highpage(page + idx, addr); + return 0; } void clear_huge_page(struct page *page, @@ -5815,7 +5825,7 @@ void clear_huge_page(struct page *page, process_huge_page(addr_hint, pages_per_huge_page, clear_subpage, page); } -static void copy_user_gigantic_page(struct folio *dst, struct folio *src, +static int copy_user_gigantic_page(struct folio *dst, struct folio *src, unsigned long addr, struct vm_area_struct *vma, unsigned int pages_per_huge_page) @@ -5829,8 +5839,13 @@ static void copy_user_gigantic_page(struct folio *dst, struct folio *src, src_page = folio_page(src, i); cond_resched(); - copy_user_highpage(dst_page, src_page, addr + i*PAGE_SIZE, vma); + if (copy_mc_user_highpage(dst_page, src_page, + addr + i*PAGE_SIZE, vma)) { + memory_failure_queue(page_to_pfn(src_page), 0); + return -EHWPOISON; + } } + return 0; } struct copy_subpage_arg { @@ -5839,16 +5854,20 @@ struct copy_subpage_arg { struct vm_area_struct *vma; }; -static void copy_subpage(unsigned long addr, int idx, void *arg) +static int copy_subpage(unsigned long addr, int idx, void *arg) { struct copy_subpage_arg *copy_arg = arg; - copy_user_highpage(copy_arg->dst + idx, copy_arg->src + idx, - addr, copy_arg->vma); + if (copy_mc_user_highpage(copy_arg->dst + idx, copy_arg->src + idx, + addr, copy_arg->vma)) { + memory_failure_queue(page_to_pfn(copy_arg->src + idx), 0); + return -EHWPOISON; + } + return 0; } -void copy_user_large_folio(struct folio *dst, struct folio *src, - unsigned long addr_hint, struct vm_area_struct *vma) +int copy_user_large_folio(struct folio *dst, struct folio *src, + unsigned long addr_hint, struct vm_area_struct *vma) { unsigned int pages_per_huge_page = folio_nr_pages(dst); unsigned long addr = addr_hint & @@ -5859,13 +5878,11 @@ void copy_user_large_folio(struct folio *dst, struct folio *src, .vma = vma, }; - if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) { - copy_user_gigantic_page(dst, src, addr, vma, - pages_per_huge_page); - return; - } + if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) + return copy_user_gigantic_page(dst, src, addr, vma, + pages_per_huge_page); - process_huge_page(addr_hint, pages_per_huge_page, copy_subpage, &arg); + return process_huge_page(addr_hint, pages_per_huge_page, copy_subpage, &arg); } long copy_folio_from_user(struct folio *dst_folio, -- cgit v1.2.3 From bb1508c24c9c361e6344308c8de2cb81d7f228ba Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Thu, 13 Apr 2023 15:12:22 +0200 Subject: mm: kmsan: apply __must_check to non-void functions Non-void KMSAN hooks may return error codes that indicate that KMSAN failed to reflect the changed memory state in the metadata (e.g. it could not create the necessary memory mappings). In such cases the callers should handle the errors to prevent the tool from using the inconsistent metadata in the future. We mark non-void hooks with __must_check so that error handling is not skipped. Link: https://lkml.kernel.org/r/20230413131223.4135168-3-glider@google.com Signed-off-by: Alexander Potapenko Reviewed-by: Marco Elver Cc: Christoph Hellwig Cc: Dipanjan Das Cc: Dmitry Vyukov Cc: Uladzislau Rezki (Sony) Signed-off-by: Andrew Morton --- include/linux/kmsan.h | 43 ++++++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 21 deletions(-) (limited to 'include') diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h index 30b17647ce3c..e0c23a32cdf0 100644 --- a/include/linux/kmsan.h +++ b/include/linux/kmsan.h @@ -54,7 +54,8 @@ void __init kmsan_init_runtime(void); * Freed pages are either returned to buddy allocator or held back to be used * as metadata pages. */ -bool __init kmsan_memblock_free_pages(struct page *page, unsigned int order); +bool __init __must_check kmsan_memblock_free_pages(struct page *page, + unsigned int order); /** * kmsan_alloc_page() - Notify KMSAN about an alloc_pages() call. @@ -137,9 +138,11 @@ void kmsan_kfree_large(const void *ptr); * vmalloc metadata address range. Returns 0 on success, callers must check * for non-zero return value. */ -int kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end, - pgprot_t prot, struct page **pages, - unsigned int page_shift); +int __must_check kmsan_vmap_pages_range_noflush(unsigned long start, + unsigned long end, + pgprot_t prot, + struct page **pages, + unsigned int page_shift); /** * kmsan_vunmap_kernel_range_noflush() - Notify KMSAN about a vunmap. @@ -163,9 +166,9 @@ void kmsan_vunmap_range_noflush(unsigned long start, unsigned long end); * virtual memory. Returns 0 on success, callers must check for non-zero return * value. */ -int kmsan_ioremap_page_range(unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int page_shift); +int __must_check kmsan_ioremap_page_range(unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int page_shift); /** * kmsan_iounmap_page_range() - Notify KMSAN about a iounmap_page_range() call. @@ -237,8 +240,8 @@ static inline void kmsan_init_runtime(void) { } -static inline bool kmsan_memblock_free_pages(struct page *page, - unsigned int order) +static inline bool __must_check kmsan_memblock_free_pages(struct page *page, + unsigned int order) { return true; } @@ -251,10 +254,9 @@ static inline void kmsan_task_exit(struct task_struct *task) { } -static inline int kmsan_alloc_page(struct page *page, unsigned int order, - gfp_t flags) +static inline void kmsan_alloc_page(struct page *page, unsigned int order, + gfp_t flags) { - return 0; } static inline void kmsan_free_page(struct page *page, unsigned int order) @@ -283,11 +285,9 @@ static inline void kmsan_kfree_large(const void *ptr) { } -static inline int kmsan_vmap_pages_range_noflush(unsigned long start, - unsigned long end, - pgprot_t prot, - struct page **pages, - unsigned int page_shift) +static inline int __must_check kmsan_vmap_pages_range_noflush( + unsigned long start, unsigned long end, pgprot_t prot, + struct page **pages, unsigned int page_shift) { return 0; } @@ -297,10 +297,11 @@ static inline void kmsan_vunmap_range_noflush(unsigned long start, { } -static inline int kmsan_ioremap_page_range(unsigned long start, - unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int page_shift) +static inline int __must_check kmsan_ioremap_page_range(unsigned long start, + unsigned long end, + phys_addr_t phys_addr, + pgprot_t prot, + unsigned int page_shift) { return 0; } -- cgit v1.2.3 From c7b23b68e2aa93f86a206222d23ccd9a21f5982a Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Thu, 13 Apr 2023 10:40:34 +0000 Subject: mm: vmscan: refactor updating current->reclaim_state During reclaim, we keep track of pages reclaimed from other means than LRU-based reclaim through scan_control->reclaim_state->reclaimed_slab, which we stash a pointer to in current task_struct. However, we keep track of more than just reclaimed slab pages through this. We also use it for clean file pages dropped through pruned inodes, and xfs buffer pages freed. Rename reclaimed_slab to reclaimed, and add a helper function that wraps updating it through current, so that future changes to this logic are contained within include/linux/swap.h. Link: https://lkml.kernel.org/r/20230413104034.1086717-4-yosryahmed@google.com Signed-off-by: Yosry Ahmed Acked-by: Michal Hocko Cc: Alexander Viro Cc: Christoph Lameter Cc: Darrick J. Wong Cc: Dave Chinner Cc: David Hildenbrand Cc: David Rientjes Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Johannes Weiner Cc: Joonsoo Kim Cc: Matthew Wilcox Cc: Miaohe Lin Cc: NeilBrown Cc: Peter Xu Cc: Roman Gushchin Cc: Shakeel Butt Cc: Tim Chen Cc: Vlastimil Babka Cc: Yu Zhao Signed-off-by: Andrew Morton --- fs/inode.c | 3 +-- fs/xfs/xfs_buf.c | 3 +-- include/linux/swap.h | 17 ++++++++++++++++- mm/slab.c | 3 +-- mm/slob.c | 6 ++---- mm/slub.c | 5 ++--- 6 files changed, 23 insertions(+), 14 deletions(-) (limited to 'include') diff --git a/fs/inode.c b/fs/inode.c index 4558dc2f1355..e60fcc41faf1 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -864,8 +864,7 @@ static enum lru_status inode_lru_isolate(struct list_head *item, __count_vm_events(KSWAPD_INODESTEAL, reap); else __count_vm_events(PGINODESTEAL, reap); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += reap; + mm_account_reclaimed_pages(reap); } iput(inode); spin_lock(lru_lock); diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 54c774af6e1c..15d1e5a7c2d3 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -286,8 +286,7 @@ xfs_buf_free_pages( if (bp->b_pages[i]) __free_page(bp->b_pages[i]); } - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += bp->b_page_count; + mm_account_reclaimed_pages(bp->b_page_count); if (bp->b_pages != bp->b_page_array) kmem_free(bp->b_pages); diff --git a/include/linux/swap.h b/include/linux/swap.h index bfc3b06b5f8f..7f7d5b9ddf7e 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -153,13 +153,28 @@ union swap_header { * memory reclaim */ struct reclaim_state { - unsigned long reclaimed_slab; + /* pages reclaimed outside of LRU-based reclaim */ + unsigned long reclaimed; #ifdef CONFIG_LRU_GEN /* per-thread mm walk data */ struct lru_gen_mm_walk *mm_walk; #endif }; +/* + * mm_account_reclaimed_pages(): account reclaimed pages outside of LRU-based + * reclaim + * @pages: number of pages reclaimed + * + * If the current process is undergoing a reclaim operation, increment the + * number of reclaimed pages by @pages. + */ +static inline void mm_account_reclaimed_pages(unsigned long pages) +{ + if (current->reclaim_state) + current->reclaim_state->reclaimed += pages; +} + #ifdef __KERNEL__ struct address_space; diff --git a/mm/slab.c b/mm/slab.c index 6b7c172158e5..bb57f7fdbae1 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1392,8 +1392,7 @@ static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; + mm_account_reclaimed_pages(1 << order); unaccount_slab(slab, order, cachep); __free_pages(&folio->page, order); } diff --git a/mm/slob.c b/mm/slob.c index fe567fcfa3a3..79cc8680c973 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -61,7 +61,7 @@ #include #include -#include /* struct reclaim_state */ +#include /* mm_account_reclaimed_pages() */ #include #include #include @@ -211,9 +211,7 @@ static void slob_free_pages(void *b, int order) { struct page *sp = virt_to_page(b); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += 1 << order; - + mm_account_reclaimed_pages(1 << order); mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, -(PAGE_SIZE << order)); __free_pages(sp, order); diff --git a/mm/slub.c b/mm/slub.c index f49d669ff604..2728d5ae4dc0 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -11,7 +11,7 @@ */ #include -#include /* struct reclaim_state */ +#include /* mm_account_reclaimed_pages() */ #include #include #include @@ -2063,8 +2063,7 @@ static void __free_slab(struct kmem_cache *s, struct slab *slab) /* Make the mapping reset visible before clearing the flag */ smp_wmb(); __folio_clear_slab(folio); - if (current->reclaim_state) - current->reclaim_state->reclaimed_slab += pages; + mm_account_reclaimed_pages(pages); unaccount_slab(slab, order, s); __free_pages(&folio->page, order); } -- cgit v1.2.3 From 7f63cf2d9b9bbe7b90f808927558a66ff737d399 Mon Sep 17 00:00:00 2001 From: Kalesh Singh Date: Thu, 13 Apr 2023 14:43:26 -0700 Subject: mm: Multi-gen LRU: remove wait_event_killable() Android 14 and later default to MGLRU [1] and field telemetry showed occasional long tail latency (>100ms) in the reclaim path. Tracing revealed priority inversion in the reclaim path. In try_to_inc_max_seq(), when high priority tasks were blocked on wait_event_killable(), the preemption of the low priority task to call wake_up_all() caused those high priority tasks to wait longer than necessary. In general, this problem is not different from others of its kind, e.g., one caused by mutex_lock(). However, it is specific to MGLRU because it introduced the new wait queue lruvec->mm_state.wait. The purpose of this new wait queue is to avoid the thundering herd problem. If many direct reclaimers rush into try_to_inc_max_seq(), only one can succeed, i.e., the one to wake up the rest, and the rest who failed might cause premature OOM kills if they do not wait. So far there is no evidence supporting this scenario, based on how often the wait has been hit. And this begs the question how useful the wait queue is in practice. Based on Minchan's recommendation, which is in line with his commit 6d4675e60135 ("mm: don't be stuck to rmap lock on reclaim path") and the rest of the MGLRU code which also uses trylock when possible, remove the wait queue. [1] https://android-review.googlesource.com/q/I7ed7fbfd6ef9ce10053347528125dd98c39e50bf Link: https://lkml.kernel.org/r/20230413214326.2147568-1-kaleshsingh@google.com Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks") Signed-off-by: Kalesh Singh Suggested-by: Minchan Kim Reported-by: Wei Wang Acked-by: Yu Zhao Cc: Minchan Kim Cc: Jan Alexander Steffens (heftig) Cc: Oleksandr Natalenko Cc: Suleiman Souhlal Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton --- include/linux/mmzone.h | 8 +--- mm/vmscan.c | 112 ++++++++++++++++++------------------------------- 2 files changed, 42 insertions(+), 78 deletions(-) (limited to 'include') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 337956748976..a4889c9d4055 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -443,18 +443,14 @@ enum { struct lru_gen_mm_state { /* set to max_seq after each iteration */ unsigned long seq; - /* where the current iteration continues (inclusive) */ + /* where the current iteration continues after */ struct list_head *head; - /* where the last iteration ended (exclusive) */ + /* where the last iteration ended before */ struct list_head *tail; - /* to wait for the last page table walker to finish */ - struct wait_queue_head wait; /* Bloom filters flip after each iteration */ unsigned long *filters[NR_BLOOM_FILTERS]; /* the mm stats for debugging */ unsigned long stats[NR_HIST_GENS][NR_MM_STATS]; - /* the number of concurrent page table walkers */ - int nr_walkers; }; struct lru_gen_mm_walk { diff --git a/mm/vmscan.c b/mm/vmscan.c index 2eb5862e99ec..8c05f4c288ce 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3450,18 +3450,13 @@ void lru_gen_del_mm(struct mm_struct *mm) for_each_node(nid) { struct lruvec *lruvec = get_lruvec(memcg, nid); - /* where the last iteration ended (exclusive) */ + /* where the current iteration continues after */ + if (lruvec->mm_state.head == &mm->lru_gen.list) + lruvec->mm_state.head = lruvec->mm_state.head->prev; + + /* where the last iteration ended before */ if (lruvec->mm_state.tail == &mm->lru_gen.list) lruvec->mm_state.tail = lruvec->mm_state.tail->next; - - /* where the current iteration continues (inclusive) */ - if (lruvec->mm_state.head != &mm->lru_gen.list) - continue; - - lruvec->mm_state.head = lruvec->mm_state.head->next; - /* the deletion ends the current iteration */ - if (lruvec->mm_state.head == &mm_list->fifo) - WRITE_ONCE(lruvec->mm_state.seq, lruvec->mm_state.seq + 1); } list_del_init(&mm->lru_gen.list); @@ -3557,68 +3552,54 @@ static bool iterate_mm_list(struct lruvec *lruvec, struct lru_gen_mm_walk *walk, struct mm_struct **iter) { bool first = false; - bool last = true; + bool last = false; struct mm_struct *mm = NULL; struct mem_cgroup *memcg = lruvec_memcg(lruvec); struct lru_gen_mm_list *mm_list = get_mm_list(memcg); struct lru_gen_mm_state *mm_state = &lruvec->mm_state; /* - * There are four interesting cases for this page table walker: - * 1. It tries to start a new iteration of mm_list with a stale max_seq; - * there is nothing left to do. - * 2. It's the first of the current generation, and it needs to reset - * the Bloom filter for the next generation. - * 3. It reaches the end of mm_list, and it needs to increment - * mm_state->seq; the iteration is done. - * 4. It's the last of the current generation, and it needs to reset the - * mm stats counters for the next generation. + * mm_state->seq is incremented after each iteration of mm_list. There + * are three interesting cases for this page table walker: + * 1. It tries to start a new iteration with a stale max_seq: there is + * nothing left to do. + * 2. It started the next iteration: it needs to reset the Bloom filter + * so that a fresh set of PTE tables can be recorded. + * 3. It ended the current iteration: it needs to reset the mm stats + * counters and tell its caller to increment max_seq. */ spin_lock(&mm_list->lock); VM_WARN_ON_ONCE(mm_state->seq + 1 < walk->max_seq); - VM_WARN_ON_ONCE(*iter && mm_state->seq > walk->max_seq); - VM_WARN_ON_ONCE(*iter && !mm_state->nr_walkers); - if (walk->max_seq <= mm_state->seq) { - if (!*iter) - last = false; + if (walk->max_seq <= mm_state->seq) goto done; - } - if (!mm_state->nr_walkers) { - VM_WARN_ON_ONCE(mm_state->head && mm_state->head != &mm_list->fifo); + if (!mm_state->head) + mm_state->head = &mm_list->fifo; - mm_state->head = mm_list->fifo.next; + if (mm_state->head == &mm_list->fifo) first = true; - } - - while (!mm && mm_state->head != &mm_list->fifo) { - mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list); + do { mm_state->head = mm_state->head->next; + if (mm_state->head == &mm_list->fifo) { + WRITE_ONCE(mm_state->seq, mm_state->seq + 1); + last = true; + break; + } /* force scan for those added after the last iteration */ - if (!mm_state->tail || mm_state->tail == &mm->lru_gen.list) { - mm_state->tail = mm_state->head; + if (!mm_state->tail || mm_state->tail == mm_state->head) { + mm_state->tail = mm_state->head->next; walk->force_scan = true; } + mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list); if (should_skip_mm(mm, walk)) mm = NULL; - } - - if (mm_state->head == &mm_list->fifo) - WRITE_ONCE(mm_state->seq, mm_state->seq + 1); + } while (!mm); done: - if (*iter && !mm) - mm_state->nr_walkers--; - if (!*iter && mm) - mm_state->nr_walkers++; - - if (mm_state->nr_walkers) - last = false; - if (*iter || last) reset_mm_stats(lruvec, walk, last); @@ -3646,9 +3627,9 @@ static bool iterate_mm_list_nowalk(struct lruvec *lruvec, unsigned long max_seq) VM_WARN_ON_ONCE(mm_state->seq + 1 < max_seq); - if (max_seq > mm_state->seq && !mm_state->nr_walkers) { - VM_WARN_ON_ONCE(mm_state->head && mm_state->head != &mm_list->fifo); - + if (max_seq > mm_state->seq) { + mm_state->head = NULL; + mm_state->tail = NULL; WRITE_ONCE(mm_state->seq, mm_state->seq + 1); reset_mm_stats(lruvec, NULL, true); success = true; @@ -4248,10 +4229,6 @@ restart: walk_pmd_range(&val, addr, next, args); - /* a racy check to curtail the waiting time */ - if (wq_has_sleeper(&walk->lruvec->mm_state.wait)) - return 1; - if (need_resched() || walk->batched >= MAX_LRU_BATCH) { end = (addr | ~PUD_MASK) + 1; goto done; @@ -4284,8 +4261,14 @@ static void walk_mm(struct lruvec *lruvec, struct mm_struct *mm, struct lru_gen_ walk->next_addr = FIRST_USER_ADDRESS; do { + DEFINE_MAX_SEQ(lruvec); + err = -EBUSY; + /* another thread might have called inc_max_seq() */ + if (walk->max_seq != max_seq) + break; + /* folio_update_gen() requires stable folio_memcg() */ if (!mem_cgroup_trylock_pages(memcg)) break; @@ -4518,25 +4501,12 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, success = iterate_mm_list(lruvec, walk, &mm); if (mm) walk_mm(lruvec, mm, walk); - - cond_resched(); } while (mm); done: - if (!success) { - if (sc->priority <= DEF_PRIORITY - 2) - wait_event_killable(lruvec->mm_state.wait, - max_seq < READ_ONCE(lrugen->max_seq)); - return false; - } + if (success) + inc_max_seq(lruvec, can_swap, force_scan); - VM_WARN_ON_ONCE(max_seq != READ_ONCE(lrugen->max_seq)); - - inc_max_seq(lruvec, can_swap, force_scan); - /* either this sees any waiters or they will see updated max_seq */ - if (wq_has_sleeper(&lruvec->mm_state.wait)) - wake_up_all(&lruvec->mm_state.wait); - - return true; + return success; } /****************************************************************************** @@ -6173,7 +6143,6 @@ void lru_gen_init_lruvec(struct lruvec *lruvec) INIT_LIST_HEAD(&lrugen->folios[gen][type][zone]); lruvec->mm_state.seq = MIN_NR_GENS; - init_waitqueue_head(&lruvec->mm_state.wait); } #ifdef CONFIG_MEMCG @@ -6206,7 +6175,6 @@ void lru_gen_exit_memcg(struct mem_cgroup *memcg) for_each_node(nid) { struct lruvec *lruvec = get_lruvec(memcg, nid); - VM_WARN_ON_ONCE(lruvec->mm_state.nr_walkers); VM_WARN_ON_ONCE(memchr_inv(lruvec->lrugen.nr_pages, 0, sizeof(lruvec->lrugen.nr_pages))); -- cgit v1.2.3 From f7b8f70ba44fb63df47b6fc3204d49ac2885de64 Mon Sep 17 00:00:00 2001 From: Luca Vizzarro Date: Fri, 14 Apr 2023 16:24:58 +0100 Subject: memfd: pass argument of memfd_fcntl as int The interface for fcntl expects the argument passed for the command F_ADD_SEALS to be of type int. The current code wrongly treats it as a long. In order to avoid access to undefined bits, we should explicitly cast the argument to int. This commit changes the signature of all the related and helper functions so that they treat the argument as int instead of long. Link: https://lkml.kernel.org/r/20230414152459.816046-5-Luca.Vizzarro@arm.com Signed-off-by: Luca Vizzarro Cc: Alexander Viro Cc: Christian Brauner Cc: Jeff Layton Cc: Chuck Lever Cc: Kevin Brodsky Cc: Vincenzo Frascino Cc: Szabolcs Nagy Cc: "Theodore Ts'o" Cc: David Laight Cc: Mark Rutland Signed-off-by: Andrew Morton --- include/linux/memfd.h | 4 ++-- mm/memfd.c | 6 +----- 2 files changed, 3 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/memfd.h b/include/linux/memfd.h index 4f1600413f91..e7abf6fa4c52 100644 --- a/include/linux/memfd.h +++ b/include/linux/memfd.h @@ -5,9 +5,9 @@ #include #ifdef CONFIG_MEMFD_CREATE -extern long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long arg); +extern long memfd_fcntl(struct file *file, unsigned int cmd, unsigned int arg); #else -static inline long memfd_fcntl(struct file *f, unsigned int c, unsigned long a) +static inline long memfd_fcntl(struct file *f, unsigned int c, unsigned int a) { return -EINVAL; } diff --git a/mm/memfd.c b/mm/memfd.c index a0a7a37e8177..69b90c31d38c 100644 --- a/mm/memfd.c +++ b/mm/memfd.c @@ -243,16 +243,12 @@ static int memfd_get_seals(struct file *file) return seals ? *seals : -EINVAL; } -long memfd_fcntl(struct file *file, unsigned int cmd, unsigned long arg) +long memfd_fcntl(struct file *file, unsigned int cmd, unsigned int arg) { long error; switch (cmd) { case F_ADD_SEALS: - /* disallow upper 32bit */ - if (arg > UINT_MAX) - return -EINVAL; - error = memfd_add_seals(file, arg); break; case F_GET_SEALS: -- cgit v1.2.3 From 4248d0083ec5817eebfb916c54950d100b3468ee Mon Sep 17 00:00:00 2001 From: Longlong Xia Date: Fri, 14 Apr 2023 10:17:41 +0800 Subject: mm: ksm: support hwpoison for ksm page hwpoison_user_mappings() is updated to support ksm pages, and add collect_procs_ksm() to collect processes when the error hit an ksm page. The difference from collect_procs_anon() is that it also needs to traverse the rmap-item list on the stable node of the ksm page. At the same time, add_to_kill_ksm() is added to handle ksm pages. And task_in_to_kill_list() is added to avoid duplicate addition of tsk to the to_kill list. This is because when scanning the list, if the pages that make up the ksm page all come from the same process, they may be added repeatedly. Link: https://lkml.kernel.org/r/20230414021741.2597273-3-xialonglong1@huawei.com Signed-off-by: Longlong Xia Tested-by: Naoya Horiguchi Reviewed-by: Kefeng Wang Cc: Miaohe Lin Cc: Nanyong Sun Signed-off-by: Andrew Morton --- include/linux/ksm.h | 11 +++++++++++ include/linux/mm.h | 7 +++++++ mm/ksm.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ mm/memory-failure.c | 34 +++++++++++++++++++++++++--------- 4 files changed, 88 insertions(+), 9 deletions(-) (limited to 'include') diff --git a/include/linux/ksm.h b/include/linux/ksm.h index 7e232ba59b86..d9e701326a88 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -51,6 +51,10 @@ struct page *ksm_might_need_to_copy(struct page *page, void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc); void folio_migrate_ksm(struct folio *newfolio, struct folio *folio); +#ifdef CONFIG_MEMORY_FAILURE +void collect_procs_ksm(struct page *page, struct list_head *to_kill, + int force_early); +#endif #else /* !CONFIG_KSM */ static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) @@ -62,6 +66,13 @@ static inline void ksm_exit(struct mm_struct *mm) { } +#ifdef CONFIG_MEMORY_FAILURE +static inline void collect_procs_ksm(struct page *page, + struct list_head *to_kill, int force_early) +{ +} +#endif + #ifdef CONFIG_MMU static inline int ksm_madvise(struct vm_area_struct *vma, unsigned long start, unsigned long end, int advice, unsigned long *vm_flags) diff --git a/include/linux/mm.h b/include/linux/mm.h index 2772a1800cf3..37554b08bb28 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3604,6 +3604,7 @@ extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, bool *migratable_cleared); void num_poisoned_pages_inc(unsigned long pfn); void num_poisoned_pages_sub(unsigned long pfn, long i); +struct task_struct *task_early_kill(struct task_struct *tsk, int force_early); #else static inline void memory_failure_queue(unsigned long pfn, int flags) { @@ -3624,6 +3625,12 @@ static inline void num_poisoned_pages_sub(unsigned long pfn, long i) } #endif +#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_KSM) +void add_to_kill_ksm(struct task_struct *tsk, struct page *p, + struct vm_area_struct *vma, struct list_head *to_kill, + unsigned long ksm_addr); +#endif + #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) extern void memblk_nr_poison_inc(unsigned long pfn); extern void memblk_nr_poison_sub(unsigned long pfn, long i); diff --git a/mm/ksm.c b/mm/ksm.c index 290a3eb6d8de..37c63310bc4e 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -2738,6 +2738,51 @@ again: goto again; } +#ifdef CONFIG_MEMORY_FAILURE +/* + * Collect processes when the error hit an ksm page. + */ +void collect_procs_ksm(struct page *page, struct list_head *to_kill, + int force_early) +{ + struct ksm_stable_node *stable_node; + struct ksm_rmap_item *rmap_item; + struct folio *folio = page_folio(page); + struct vm_area_struct *vma; + struct task_struct *tsk; + + stable_node = folio_stable_node(folio); + if (!stable_node) + return; + hlist_for_each_entry(rmap_item, &stable_node->hlist, hlist) { + struct anon_vma *av = rmap_item->anon_vma; + + anon_vma_lock_read(av); + read_lock(&tasklist_lock); + for_each_process(tsk) { + struct anon_vma_chain *vmac; + unsigned long addr; + struct task_struct *t = + task_early_kill(tsk, force_early); + if (!t) + continue; + anon_vma_interval_tree_foreach(vmac, &av->rb_root, 0, + ULONG_MAX) + { + vma = vmac->vma; + if (vma->vm_mm == t->mm) { + addr = rmap_item->address & PAGE_MASK; + add_to_kill_ksm(t, page, vma, to_kill, + addr); + } + } + } + read_unlock(&tasklist_lock); + anon_vma_unlock_read(av); + } +} +#endif + #ifdef CONFIG_MIGRATION void folio_migrate_ksm(struct folio *newfolio, struct folio *folio) { diff --git a/mm/memory-failure.c b/mm/memory-failure.c index bb09999108ef..f69c410fb9f9 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -455,6 +455,27 @@ static void add_to_kill_anon_file(struct task_struct *tsk, struct page *p, __add_to_kill(tsk, p, vma, to_kill, 0, FSDAX_INVALID_PGOFF); } +#ifdef CONFIG_KSM +static bool task_in_to_kill_list(struct list_head *to_kill, + struct task_struct *tsk) +{ + struct to_kill *tk, *next; + + list_for_each_entry_safe(tk, next, to_kill, nd) { + if (tk->tsk == tsk) + return true; + } + + return false; +} +void add_to_kill_ksm(struct task_struct *tsk, struct page *p, + struct vm_area_struct *vma, struct list_head *to_kill, + unsigned long ksm_addr) +{ + if (!task_in_to_kill_list(to_kill, tsk)) + __add_to_kill(tsk, p, vma, to_kill, ksm_addr, FSDAX_INVALID_PGOFF); +} +#endif /* * Kill the processes that have been collected earlier. * @@ -534,8 +555,7 @@ static struct task_struct *find_early_kill_thread(struct task_struct *tsk) * processes sharing the same error page,if the process is "early kill", the * task_struct of the dedicated thread will also be returned. */ -static struct task_struct *task_early_kill(struct task_struct *tsk, - int force_early) +struct task_struct *task_early_kill(struct task_struct *tsk, int force_early) { if (!tsk->mm) return NULL; @@ -666,8 +686,9 @@ static void collect_procs(struct page *page, struct list_head *tokill, { if (!page->mapping) return; - - if (PageAnon(page)) + if (unlikely(PageKsm(page))) + collect_procs_ksm(page, tokill, force_early); + else if (PageAnon(page)) collect_procs_anon(page, tokill, force_early); else collect_procs_file(page, tokill, force_early); @@ -1522,11 +1543,6 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, if (!page_mapped(hpage)) return true; - if (PageKsm(p)) { - pr_err("%#lx: can't handle KSM pages.\n", pfn); - return false; - } - if (PageSwapCache(p)) { pr_err("%#lx: keeping poisoned page in swap cache\n", pfn); ttu &= ~TTU_HWPOISON; -- cgit v1.2.3 From 465e5e6a1698f3325f5d2262d2875779b06b50c7 Mon Sep 17 00:00:00 2001 From: Pankaj Raghav Date: Mon, 17 Apr 2023 14:36:15 +0200 Subject: fs/buffer: add folio_set_bh helper Patch series "convert create_page_buffers to folio_create_buffers". One of the first kernel panic we hit when we try to increase the block size > 4k is inside create_page_buffers()[1]. Even though buffer.c function do not support large folios (folios > PAGE_SIZE) at the moment, these changes are required when we want to remove that constraint. This patch (of 4): The folio version of set_bh_page(). This is required to convert create_page_buffers() to folio_create_buffers() later in the series. Link: https://lkml.kernel.org/r/20230417123618.22094-1-p.raghav@samsung.com Link: https://lkml.kernel.org/r/20230417123618.22094-2-p.raghav@samsung.com Signed-off-by: Pankaj Raghav Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Hannes Reinecke Cc: Alexander Viro Cc: Christian Brauner Cc: Luis Chamberlain Signed-off-by: Andrew Morton --- fs/buffer.c | 15 +++++++++++++++ include/linux/buffer_head.h | 2 ++ 2 files changed, 17 insertions(+) (limited to 'include') diff --git a/fs/buffer.c b/fs/buffer.c index 9e1e2add541e..009d950fbf42 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1485,6 +1485,21 @@ void set_bh_page(struct buffer_head *bh, } EXPORT_SYMBOL(set_bh_page); +void folio_set_bh(struct buffer_head *bh, struct folio *folio, + unsigned long offset) +{ + bh->b_folio = folio; + BUG_ON(offset >= folio_size(folio)); + if (folio_test_highmem(folio)) + /* + * This catches illegal uses and preserves the offset: + */ + bh->b_data = (char *)(0 + offset); + else + bh->b_data = folio_address(folio) + offset; +} +EXPORT_SYMBOL(folio_set_bh); + /* * Called when truncating a buffer on a page completely. */ diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 8f14dca5fed7..7e92d23f4782 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -196,6 +196,8 @@ void mark_buffer_write_io_error(struct buffer_head *bh); void touch_buffer(struct buffer_head *bh); void set_bh_page(struct buffer_head *bh, struct page *page, unsigned long offset); +void folio_set_bh(struct buffer_head *bh, struct folio *folio, + unsigned long offset); bool try_to_free_buffers(struct folio *); struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, bool retry); -- cgit v1.2.3 From c71124a8afa441af203d2001a92c91f114446687 Mon Sep 17 00:00:00 2001 From: Pankaj Raghav Date: Mon, 17 Apr 2023 14:36:16 +0200 Subject: buffer: add folio_alloc_buffers() helper Folio version of alloc_page_buffers() helper. This is required to convert create_page_buffers() to folio_create_buffers() later in the series. alloc_page_buffers() has been modified to call folio_alloc_buffers() which adds one call to compound_head() but folio_alloc_buffers() removes one call to compound_head() compared to the existing alloc_page_buffers() implementation. Link: https://lkml.kernel.org/r/20230417123618.22094-3-p.raghav@samsung.com Signed-off-by: Pankaj Raghav Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Hannes Reinecke Cc: Alexander Viro Cc: Christian Brauner Cc: Luis Chamberlain Signed-off-by: Andrew Morton --- fs/buffer.c | 23 +++++++++++++++-------- include/linux/buffer_head.h | 2 ++ 2 files changed, 17 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/fs/buffer.c b/fs/buffer.c index 009d950fbf42..bbd4aa670262 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -843,7 +843,7 @@ int remove_inode_buffers(struct inode *inode) } /* - * Create the appropriate buffers when given a page for data area and + * Create the appropriate buffers when given a folio for data area and * the size of each buffer.. Use the bh->b_this_page linked list to * follow the buffers created. Return NULL if unable to create more * buffers. @@ -851,8 +851,8 @@ int remove_inode_buffers(struct inode *inode) * The retry flag is used to differentiate async IO (paging, swapping) * which may not fail from ordinary buffer allocations. */ -struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, - bool retry) +struct buffer_head *folio_alloc_buffers(struct folio *folio, unsigned long size, + bool retry) { struct buffer_head *bh, *head; gfp_t gfp = GFP_NOFS | __GFP_ACCOUNT; @@ -862,12 +862,12 @@ struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, if (retry) gfp |= __GFP_NOFAIL; - /* The page lock pins the memcg */ - memcg = page_memcg(page); + /* The folio lock pins the memcg */ + memcg = folio_memcg(folio); old_memcg = set_active_memcg(memcg); head = NULL; - offset = PAGE_SIZE; + offset = folio_size(folio); while ((offset -= size) >= 0) { bh = alloc_buffer_head(gfp); if (!bh) @@ -879,8 +879,8 @@ struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, bh->b_size = size; - /* Link the buffer to its page */ - set_bh_page(bh, page, offset); + /* Link the buffer to its folio */ + folio_set_bh(bh, folio, offset); } out: set_active_memcg(old_memcg); @@ -899,6 +899,13 @@ no_grow: goto out; } +EXPORT_SYMBOL_GPL(folio_alloc_buffers); + +struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, + bool retry) +{ + return folio_alloc_buffers(page_folio(page), size, retry); +} EXPORT_SYMBOL_GPL(alloc_page_buffers); static inline void diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 7e92d23f4782..0b14eab41bd1 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -199,6 +199,8 @@ void set_bh_page(struct buffer_head *bh, void folio_set_bh(struct buffer_head *bh, struct folio *folio, unsigned long offset); bool try_to_free_buffers(struct folio *); +struct buffer_head *folio_alloc_buffers(struct folio *folio, unsigned long size, + bool retry); struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, bool retry); void create_empty_buffers(struct page *, unsigned long, -- cgit v1.2.3 From 8e2e17560bed73c2a73c94cbe378719f6cf850ee Mon Sep 17 00:00:00 2001 From: Pankaj Raghav Date: Mon, 17 Apr 2023 14:36:17 +0200 Subject: fs/buffer: add folio_create_empty_buffers helper Folio version of create_empty_buffers(). This is required to convert create_page_buffers() to folio_create_buffers() later in the series. It removes several calls to compound_head() as it works directly on folio compared to create_empty_buffers(). Hence, create_empty_buffers() has been modified to call folio_create_empty_buffers(). Link: https://lkml.kernel.org/r/20230417123618.22094-4-p.raghav@samsung.com Signed-off-by: Pankaj Raghav Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Hannes Reinecke Cc: Alexander Viro Cc: Christian Brauner Cc: Luis Chamberlain Signed-off-by: Andrew Morton --- fs/buffer.c | 28 +++++++++++++++++----------- include/linux/buffer_head.h | 2 ++ 2 files changed, 19 insertions(+), 11 deletions(-) (limited to 'include') diff --git a/fs/buffer.c b/fs/buffer.c index bbd4aa670262..e6266bf7eeea 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1594,18 +1594,17 @@ out: } EXPORT_SYMBOL(block_invalidate_folio); - /* * We attach and possibly dirty the buffers atomically wrt * block_dirty_folio() via private_lock. try_to_free_buffers - * is already excluded via the page lock. + * is already excluded via the folio lock. */ -void create_empty_buffers(struct page *page, - unsigned long blocksize, unsigned long b_state) +void folio_create_empty_buffers(struct folio *folio, unsigned long blocksize, + unsigned long b_state) { struct buffer_head *bh, *head, *tail; - head = alloc_page_buffers(page, blocksize, true); + head = folio_alloc_buffers(folio, blocksize, true); bh = head; do { bh->b_state |= b_state; @@ -1614,19 +1613,26 @@ void create_empty_buffers(struct page *page, } while (bh); tail->b_this_page = head; - spin_lock(&page->mapping->private_lock); - if (PageUptodate(page) || PageDirty(page)) { + spin_lock(&folio->mapping->private_lock); + if (folio_test_uptodate(folio) || folio_test_dirty(folio)) { bh = head; do { - if (PageDirty(page)) + if (folio_test_dirty(folio)) set_buffer_dirty(bh); - if (PageUptodate(page)) + if (folio_test_uptodate(folio)) set_buffer_uptodate(bh); bh = bh->b_this_page; } while (bh != head); } - attach_page_private(page, head); - spin_unlock(&page->mapping->private_lock); + folio_attach_private(folio, head); + spin_unlock(&folio->mapping->private_lock); +} +EXPORT_SYMBOL(folio_create_empty_buffers); + +void create_empty_buffers(struct page *page, + unsigned long blocksize, unsigned long b_state) +{ + folio_create_empty_buffers(page_folio(page), blocksize, b_state); } EXPORT_SYMBOL(create_empty_buffers); diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 0b14eab41bd1..1520793c72da 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -205,6 +205,8 @@ struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, bool retry); void create_empty_buffers(struct page *, unsigned long, unsigned long b_state); +void folio_create_empty_buffers(struct folio *folio, unsigned long blocksize, + unsigned long b_state); void end_buffer_read_sync(struct buffer_head *bh, int uptodate); void end_buffer_write_sync(struct buffer_head *bh, int uptodate); void end_buffer_async_write(struct buffer_head *bh, int uptodate); -- cgit v1.2.3 From 4bf4f155bfbc77a12ad2c9e12d9f57718adb9a5c Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Mon, 17 Apr 2023 19:48:07 +0800 Subject: mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list() Both of them change the arg from page_list to folio_list when convert them to use a folio, but not the declaration, let's correct it, also move the reclaim_pages() from swap.h to internal.h as it only used in mm. Link: https://lkml.kernel.org/r/20230417114807.186786-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Reviwed-by: Matthew Wilcox (Oracle) Reviewed-by: SeongJae Park Reviewed-by: David Hildenbrand Cc: Hugh Dickins Signed-off-by: Andrew Morton --- include/linux/swap.h | 1 - mm/internal.h | 3 ++- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/swap.h b/include/linux/swap.h index 7f7d5b9ddf7e..3c69cb653cb9 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -442,7 +442,6 @@ extern unsigned long shrink_all_memory(unsigned long nr_pages); extern int vm_swappiness; long remove_mapping(struct address_space *mapping, struct folio *folio); -extern unsigned long reclaim_pages(struct list_head *page_list); #ifdef CONFIG_NUMA extern int node_reclaim_mode; extern int sysctl_min_unmapped_ratio; diff --git a/mm/internal.h b/mm/internal.h index 6483db57a31f..68410c6d97ac 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -783,8 +783,9 @@ extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, unsigned long, unsigned long); extern void set_pageblock_order(void); +unsigned long reclaim_pages(struct list_head *folio_list); unsigned int reclaim_clean_pages_from_list(struct zone *zone, - struct list_head *page_list); + struct list_head *folio_list); /* The ALLOC_WMARK bits are used as an index to zone->watermark */ #define ALLOC_WMARK_MIN WMARK_MIN #define ALLOC_WMARK_LOW WMARK_LOW -- cgit v1.2.3 From d7597f59d1d33e9efbffa7060deb9ee5bd119e62 Mon Sep 17 00:00:00 2001 From: Stefan Roesch Date: Mon, 17 Apr 2023 22:13:40 -0700 Subject: mm: add new api to enable ksm per process Patch series "mm: process/cgroup ksm support", v9. So far KSM can only be enabled by calling madvise for memory regions. To be able to use KSM for more workloads, KSM needs to have the ability to be enabled / disabled at the process / cgroup level. Use case 1: The madvise call is not available in the programming language. An example for this are programs with forked workloads using a garbage collected language without pointers. In such a language madvise cannot be made available. In addition the addresses of objects get moved around as they are garbage collected. KSM sharing needs to be enabled "from the outside" for these type of workloads. Use case 2: The same interpreter can also be used for workloads where KSM brings no benefit or even has overhead. We'd like to be able to enable KSM on a workload by workload basis. Use case 3: With the madvise call sharing opportunities are only enabled for the current process: it is a workload-local decision. A considerable number of sharing opportunities may exist across multiple workloads or jobs (if they are part of the same security domain). Only a higler level entity like a job scheduler or container can know for certain if its running one or more instances of a job. That job scheduler however doesn't have the necessary internal workload knowledge to make targeted madvise calls. Security concerns: In previous discussions security concerns have been brought up. The problem is that an individual workload does not have the knowledge about what else is running on a machine. Therefore it has to be very conservative in what memory areas can be shared or not. However, if the system is dedicated to running multiple jobs within the same security domain, its the job scheduler that has the knowledge that sharing can be safely enabled and is even desirable. Performance: Experiments with using UKSM have shown a capacity increase of around 20%. Here are the metrics from an instagram workload (taken from a machine with 64GB main memory): full_scans: 445 general_profit: 20158298048 max_page_sharing: 256 merge_across_nodes: 1 pages_shared: 129547 pages_sharing: 5119146 pages_to_scan: 4000 pages_unshared: 1760924 pages_volatile: 10761341 run: 1 sleep_millisecs: 20 stable_node_chains: 167 stable_node_chains_prune_millisecs: 2000 stable_node_dups: 2751 use_zero_pages: 0 zero_pages_sharing: 0 After the service is running for 30 minutes to an hour, 4 to 5 million shared pages are common for this workload when using KSM. Detailed changes: 1. New options for prctl system command This patch series adds two new options to the prctl system call. The first one allows to enable KSM at the process level and the second one to query the setting. The setting will be inherited by child processes. With the above setting, KSM can be enabled for the seed process of a cgroup and all processes in the cgroup will inherit the setting. 2. Changes to KSM processing When KSM is enabled at the process level, the KSM code will iterate over all the VMA's and enable KSM for the eligible VMA's. When forking a process that has KSM enabled, the setting will be inherited by the new child process. 3. Add general_profit metric The general_profit metric of KSM is specified in the documentation, but not calculated. This adds the general profit metric to /sys/kernel/debug/mm/ksm. 4. Add more metrics to ksm_stat This adds the process profit metric to /proc//ksm_stat. 5. Add more tests to ksm_tests and ksm_functional_tests This adds an option to specify the merge type to the ksm_tests. This allows to test madvise and prctl KSM. It also adds a two new tests to ksm_functional_tests: one to test the new prctl options and the other one is a fork test to verify that the KSM process setting is inherited by client processes. This patch (of 3): So far KSM can only be enabled by calling madvise for memory regions. To be able to use KSM for more workloads, KSM needs to have the ability to be enabled / disabled at the process / cgroup level. 1. New options for prctl system command This patch series adds two new options to the prctl system call. The first one allows to enable KSM at the process level and the second one to query the setting. The setting will be inherited by child processes. With the above setting, KSM can be enabled for the seed process of a cgroup and all processes in the cgroup will inherit the setting. 2. Changes to KSM processing When KSM is enabled at the process level, the KSM code will iterate over all the VMA's and enable KSM for the eligible VMA's. When forking a process that has KSM enabled, the setting will be inherited by the new child process. 1) Introduce new MMF_VM_MERGE_ANY flag This introduces the new flag MMF_VM_MERGE_ANY flag. When this flag is set, kernel samepage merging (ksm) gets enabled for all vma's of a process. 2) Setting VM_MERGEABLE on VMA creation When a VMA is created, if the MMF_VM_MERGE_ANY flag is set, the VM_MERGEABLE flag will be set for this VMA. 3) support disabling of ksm for a process This adds the ability to disable ksm for a process if ksm has been enabled for the process with prctl. 4) add new prctl option to get and set ksm for a process This adds two new options to the prctl system call - enable ksm for all vmas of a process (if the vmas support it). - query if ksm has been enabled for a process. 3. Disabling MMF_VM_MERGE_ANY for storage keys in s390 In the s390 architecture when storage keys are used, the MMF_VM_MERGE_ANY will be disabled. Link: https://lkml.kernel.org/r/20230418051342.1919757-1-shr@devkernel.io Link: https://lkml.kernel.org/r/20230418051342.1919757-2-shr@devkernel.io Signed-off-by: Stefan Roesch Acked-by: David Hildenbrand Cc: David Hildenbrand Cc: Johannes Weiner Cc: Michal Hocko Cc: Rik van Riel Cc: Bagas Sanjaya Signed-off-by: Andrew Morton --- arch/s390/mm/gmap.c | 7 +++ include/linux/ksm.h | 21 ++++++++- include/linux/sched/coredump.h | 1 + include/uapi/linux/prctl.h | 2 + kernel/sys.c | 27 +++++++++++ mm/ksm.c | 104 ++++++++++++++++++++++++++++++++++------- mm/mmap.c | 3 ++ 7 files changed, 146 insertions(+), 19 deletions(-) (limited to 'include') diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index 5a716bdcba05..0949811761e6 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -2591,6 +2591,13 @@ int gmap_mark_unmergeable(void) int ret; VMA_ITERATOR(vmi, mm, 0); + /* + * Make sure to disable KSM (if enabled for the whole process or + * individual VMAs). Note that nothing currently hinders user space + * from re-enabling it. + */ + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); + for_each_vma(vmi, vma) { /* Copy vm_flags to avoid partial modifications in ksm_madvise */ vm_flags = vma->vm_flags; diff --git a/include/linux/ksm.h b/include/linux/ksm.h index d9e701326a88..4647b0c70c12 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -18,13 +18,26 @@ #ifdef CONFIG_KSM int ksm_madvise(struct vm_area_struct *vma, unsigned long start, unsigned long end, int advice, unsigned long *vm_flags); + +void ksm_add_vma(struct vm_area_struct *vma); +int ksm_enable_merge_any(struct mm_struct *mm); + int __ksm_enter(struct mm_struct *mm); void __ksm_exit(struct mm_struct *mm); static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) { - if (test_bit(MMF_VM_MERGEABLE, &oldmm->flags)) - return __ksm_enter(mm); + int ret; + + if (test_bit(MMF_VM_MERGEABLE, &oldmm->flags)) { + ret = __ksm_enter(mm); + if (ret) + return ret; + } + + if (test_bit(MMF_VM_MERGE_ANY, &oldmm->flags)) + set_bit(MMF_VM_MERGE_ANY, &mm->flags); + return 0; } @@ -57,6 +70,10 @@ void collect_procs_ksm(struct page *page, struct list_head *to_kill, #endif #else /* !CONFIG_KSM */ +static inline void ksm_add_vma(struct vm_area_struct *vma) +{ +} + static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) { return 0; diff --git a/include/linux/sched/coredump.h b/include/linux/sched/coredump.h index 0e17ae7fbfd3..0ee96ea7a0e9 100644 --- a/include/linux/sched/coredump.h +++ b/include/linux/sched/coredump.h @@ -90,4 +90,5 @@ static inline int get_dumpable(struct mm_struct *mm) #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK |\ MMF_DISABLE_THP_MASK | MMF_HAS_MDWE_MASK) +#define MMF_VM_MERGE_ANY 29 #endif /* _LINUX_SCHED_COREDUMP_H */ diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index b99c0be72577..f23d9a16507f 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -292,4 +292,6 @@ struct prctl_mm_map { #define PR_GET_AUXV 0x41555856 +#define PR_SET_MEMORY_MERGE 67 +#define PR_GET_MEMORY_MERGE 68 #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 26c1399e0654..72cdb16e2636 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -2687,6 +2688,32 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, case PR_SET_VMA: error = prctl_set_vma(arg2, arg3, arg4, arg5); break; +#ifdef CONFIG_KSM + case PR_SET_MEMORY_MERGE: + if (arg3 || arg4 || arg5) + return -EINVAL; + if (mmap_write_lock_killable(me->mm)) + return -EINTR; + + if (arg2) { + error = ksm_enable_merge_any(me->mm); + } else { + /* + * TODO: we might want disable KSM on all VMAs and + * trigger unsharing to completely disable KSM. + */ + clear_bit(MMF_VM_MERGE_ANY, &me->mm->flags); + error = 0; + } + mmap_write_unlock(me->mm); + break; + case PR_GET_MEMORY_MERGE: + if (arg2 || arg3 || arg4 || arg5) + return -EINVAL; + + error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags); + break; +#endif default: error = -EINVAL; break; diff --git a/mm/ksm.c b/mm/ksm.c index 37c63310bc4e..35ac6c741572 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -515,6 +515,28 @@ static int break_ksm(struct vm_area_struct *vma, unsigned long addr) return (ret & VM_FAULT_OOM) ? -ENOMEM : 0; } +static bool vma_ksm_compatible(struct vm_area_struct *vma) +{ + if (vma->vm_flags & (VM_SHARED | VM_MAYSHARE | VM_PFNMAP | + VM_IO | VM_DONTEXPAND | VM_HUGETLB | + VM_MIXEDMAP)) + return false; /* just ignore the advice */ + + if (vma_is_dax(vma)) + return false; + +#ifdef VM_SAO + if (vma->vm_flags & VM_SAO) + return false; +#endif +#ifdef VM_SPARC_ADI + if (vma->vm_flags & VM_SPARC_ADI) + return false; +#endif + + return true; +} + static struct vm_area_struct *find_mergeable_vma(struct mm_struct *mm, unsigned long addr) { @@ -1026,6 +1048,7 @@ mm_exiting: mm_slot_free(mm_slot_cache, mm_slot); clear_bit(MMF_VM_MERGEABLE, &mm->flags); + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); mmdrop(mm); } else spin_unlock(&ksm_mmlist_lock); @@ -2408,6 +2431,7 @@ no_vmas: mm_slot_free(mm_slot_cache, mm_slot); clear_bit(MMF_VM_MERGEABLE, &mm->flags); + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); mmap_read_unlock(mm); mmdrop(mm); } else { @@ -2485,6 +2509,66 @@ static int ksm_scan_thread(void *nothing) return 0; } +static void __ksm_add_vma(struct vm_area_struct *vma) +{ + unsigned long vm_flags = vma->vm_flags; + + if (vm_flags & VM_MERGEABLE) + return; + + if (vma_ksm_compatible(vma)) + vm_flags_set(vma, VM_MERGEABLE); +} + +/** + * ksm_add_vma - Mark vma as mergeable if compatible + * + * @vma: Pointer to vma + */ +void ksm_add_vma(struct vm_area_struct *vma) +{ + struct mm_struct *mm = vma->vm_mm; + + if (test_bit(MMF_VM_MERGE_ANY, &mm->flags)) + __ksm_add_vma(vma); +} + +static void ksm_add_vmas(struct mm_struct *mm) +{ + struct vm_area_struct *vma; + + VMA_ITERATOR(vmi, mm, 0); + for_each_vma(vmi, vma) + __ksm_add_vma(vma); +} + +/** + * ksm_enable_merge_any - Add mm to mm ksm list and enable merging on all + * compatible VMA's + * + * @mm: Pointer to mm + * + * Returns 0 on success, otherwise error code + */ +int ksm_enable_merge_any(struct mm_struct *mm) +{ + int err; + + if (test_bit(MMF_VM_MERGE_ANY, &mm->flags)) + return 0; + + if (!test_bit(MMF_VM_MERGEABLE, &mm->flags)) { + err = __ksm_enter(mm); + if (err) + return err; + } + + set_bit(MMF_VM_MERGE_ANY, &mm->flags); + ksm_add_vmas(mm); + + return 0; +} + int ksm_madvise(struct vm_area_struct *vma, unsigned long start, unsigned long end, int advice, unsigned long *vm_flags) { @@ -2493,25 +2577,10 @@ int ksm_madvise(struct vm_area_struct *vma, unsigned long start, switch (advice) { case MADV_MERGEABLE: - /* - * Be somewhat over-protective for now! - */ - if (*vm_flags & (VM_MERGEABLE | VM_SHARED | VM_MAYSHARE | - VM_PFNMAP | VM_IO | VM_DONTEXPAND | - VM_HUGETLB | VM_MIXEDMAP)) - return 0; /* just ignore the advice */ - - if (vma_is_dax(vma)) + if (vma->vm_flags & VM_MERGEABLE) return 0; - -#ifdef VM_SAO - if (*vm_flags & VM_SAO) + if (!vma_ksm_compatible(vma)) return 0; -#endif -#ifdef VM_SPARC_ADI - if (*vm_flags & VM_SPARC_ADI) - return 0; -#endif if (!test_bit(MMF_VM_MERGEABLE, &mm->flags)) { err = __ksm_enter(mm); @@ -2615,6 +2684,7 @@ void __ksm_exit(struct mm_struct *mm) if (easy_to_free) { mm_slot_free(mm_slot_cache, mm_slot); + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); clear_bit(MMF_VM_MERGEABLE, &mm->flags); mmdrop(mm); } else if (mm_slot) { diff --git a/mm/mmap.c b/mm/mmap.c index 790cc62c0038..51b6976fd525 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -46,6 +46,7 @@ #include #include #include +#include #include #include @@ -2729,6 +2730,7 @@ unmap_writable: if (file && vm_flags & VM_SHARED) mapping_unmap_writable(file->f_mapping); file = vma->vm_file; + ksm_add_vma(vma); expanded: perf_event_mmap(vma); @@ -3001,6 +3003,7 @@ static int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, goto mas_store_fail; mm->map_count++; + ksm_add_vma(vma); out: perf_event_mmap(vma); mm->total_vm += len >> PAGE_SHIFT; -- cgit v1.2.3 From d21077fbc2fc987c2e593c34dc3b4d84e546dc9f Mon Sep 17 00:00:00 2001 From: Stefan Roesch Date: Mon, 17 Apr 2023 22:13:41 -0700 Subject: mm: add new KSM process and sysfs knobs This adds the general_profit KSM sysfs knob and the process profit metric knobs to ksm_stat. 1) expose general_profit metric The documentation mentions a general profit metric, however this metric is not calculated. In addition the formula depends on the size of internal structures, which makes it more difficult for an administrator to make the calculation. Adding the metric for a better user experience. 2) document general_profit sysfs knob 3) calculate ksm process profit metric The ksm documentation mentions the process profit metric and how to calculate it. This adds the calculation of the metric. 4) mm: expose ksm process profit metric in ksm_stat This exposes the ksm process profit metric in /proc//ksm_stat. The documentation mentions the formula for the ksm process profit metric, however it does not calculate it. In addition the formula depends on the size of internal structures. So it makes sense to expose it. 5) document new procfs ksm knobs Link: https://lkml.kernel.org/r/20230418051342.1919757-3-shr@devkernel.io Signed-off-by: Stefan Roesch Reviewed-by: Bagas Sanjaya Acked-by: David Hildenbrand Cc: David Hildenbrand Cc: Johannes Weiner Cc: Michal Hocko Cc: Rik van Riel Signed-off-by: Andrew Morton --- Documentation/ABI/testing/sysfs-kernel-mm-ksm | 8 ++++++++ Documentation/admin-guide/mm/ksm.rst | 5 ++++- fs/proc/base.c | 3 +++ include/linux/ksm.h | 5 +++++ mm/ksm.c | 21 +++++++++++++++++++++ 5 files changed, 41 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-ksm b/Documentation/ABI/testing/sysfs-kernel-mm-ksm index d244674a9480..6041a025b65a 100644 --- a/Documentation/ABI/testing/sysfs-kernel-mm-ksm +++ b/Documentation/ABI/testing/sysfs-kernel-mm-ksm @@ -51,3 +51,11 @@ Description: Control merging pages across different NUMA nodes. When it is set to 0 only pages from the same node are merged, otherwise pages from all nodes can be merged together (default). + +What: /sys/kernel/mm/ksm/general_profit +Date: April 2023 +KernelVersion: 6.4 +Contact: Linux memory management mailing list +Description: Measure how effective KSM is. + general_profit: how effective is KSM. The formula for the + calculation is in Documentation/admin-guide/mm/ksm.rst. diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst index eed51a910c94..551083a396fb 100644 --- a/Documentation/admin-guide/mm/ksm.rst +++ b/Documentation/admin-guide/mm/ksm.rst @@ -157,6 +157,8 @@ stable_node_chains_prune_millisecs The effectiveness of KSM and MADV_MERGEABLE is shown in ``/sys/kernel/mm/ksm/``: +general_profit + how effective is KSM. The calculation is explained below. pages_shared how many shared pages are being used pages_sharing @@ -207,7 +209,8 @@ several times, which are unprofitable memory consumed. ksm_rmap_items * sizeof(rmap_item). where ksm_merging_pages is shown under the directory ``/proc//``, - and ksm_rmap_items is shown in ``/proc//ksm_stat``. + and ksm_rmap_items is shown in ``/proc//ksm_stat``. The process profit + is also shown in ``/proc//ksm_stat`` as ksm_process_profit. From the perspective of application, a high ratio of ``ksm_rmap_items`` to ``ksm_merging_pages`` means a bad madvise-applied policy, so developers or diff --git a/fs/proc/base.c b/fs/proc/base.c index 5e0e0ccd47aa..96a6a08c8235 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -96,6 +96,7 @@ #include #include #include +#include #include #include "internal.h" #include "fd.h" @@ -3207,6 +3208,8 @@ static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns, mm = get_task_mm(task); if (mm) { seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items); + seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages); + seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm)); mmput(mm); } diff --git a/include/linux/ksm.h b/include/linux/ksm.h index 4647b0c70c12..7a9b76fb6c3f 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -68,6 +68,11 @@ void folio_migrate_ksm(struct folio *newfolio, struct folio *folio); void collect_procs_ksm(struct page *page, struct list_head *to_kill, int force_early); #endif + +#ifdef CONFIG_PROC_FS +long ksm_process_profit(struct mm_struct *); +#endif /* CONFIG_PROC_FS */ + #else /* !CONFIG_KSM */ static inline void ksm_add_vma(struct vm_area_struct *vma) diff --git a/mm/ksm.c b/mm/ksm.c index 35ac6c741572..9e48258985d2 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -3007,6 +3007,14 @@ static void wait_while_offlining(void) } #endif /* CONFIG_MEMORY_HOTREMOVE */ +#ifdef CONFIG_PROC_FS +long ksm_process_profit(struct mm_struct *mm) +{ + return mm->ksm_merging_pages * PAGE_SIZE - + mm->ksm_rmap_items * sizeof(struct ksm_rmap_item); +} +#endif /* CONFIG_PROC_FS */ + #ifdef CONFIG_SYSFS /* * This all compiles without CONFIG_SYSFS, but is a waste of space. @@ -3271,6 +3279,18 @@ static ssize_t pages_volatile_show(struct kobject *kobj, } KSM_ATTR_RO(pages_volatile); +static ssize_t general_profit_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + long general_profit; + + general_profit = ksm_pages_sharing * PAGE_SIZE - + ksm_rmap_items * sizeof(struct ksm_rmap_item); + + return sysfs_emit(buf, "%ld\n", general_profit); +} +KSM_ATTR_RO(general_profit); + static ssize_t stable_node_dups_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { @@ -3335,6 +3355,7 @@ static struct attribute *ksm_attrs[] = { &stable_node_dups_attr.attr, &stable_node_chains_prune_millisecs_attr.attr, &use_zero_pages_attr.attr, + &general_profit_attr.attr, NULL, }; -- cgit v1.2.3 From f724392415b3e1ae844d2766669c0d955fe9a17b Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 18 Apr 2023 22:22:02 -0700 Subject: hugetlb: pte_alloc_huge() to replace huge pte_alloc_map() Some architectures can have their hugetlb pages down at the lowest PTE level: their huge_pte_alloc() using pte_alloc_map(), but without any following pte_unmap(). Since none of these arches uses CONFIG_HIGHPTE, this is not seen as a problem at present; but would become a problem if forthcoming changes were to add an rcu_read_lock() into pte_offset_map(), with the rcu_read_unlock() expected in pte_unmap(). Similarly in their huge_pte_offset(): pte_offset_kernel() is good enough for that, but it's probably less confusing if we define pte_offset_huge() along with pte_alloc_huge(). Only define them without CONFIG_HIGHPTE: so there would be a build error to signal if ever more work is needed. For ease of development, define these now for 6.4-rc1, ahead of any use: then architectures can integrate patches using them, independent from mm. Link: https://lkml.kernel.org/r/ae9e7d98-8a3a-cfd9-4762-bcddffdf96cf@google.com Signed-off-by: Hugh Dickins Reviewed-by: Mike Kravetz Cc: Muchun Song Signed-off-by: Andrew Morton --- include/linux/hugetlb.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'include') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 28703fe22386..cbe1e97a15a1 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -191,6 +191,23 @@ extern struct list_head huge_boot_pages; /* arch callbacks */ +#ifndef CONFIG_HIGHPTE +/* + * pte_offset_huge() and pte_alloc_huge() are helpers for those architectures + * which may go down to the lowest PTE level in their huge_pte_offset() and + * huge_pte_alloc(): to avoid reliance on pte_offset_map() without pte_unmap(). + */ +static inline pte_t *pte_offset_huge(pmd_t *pmd, unsigned long address) +{ + return pte_offset_kernel(pmd, address); +} +static inline pte_t *pte_alloc_huge(struct mm_struct *mm, pmd_t *pmd, + unsigned long address) +{ + return pte_alloc(mm, pmd) ? NULL : pte_offset_huge(pmd, address); +} +#endif + pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long sz); /* -- cgit v1.2.3