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authorRussell King <rmk+kernel@arm.linux.org.uk>2014-08-05 11:27:13 +0200
committerRussell King <rmk+kernel@arm.linux.org.uk>2014-08-05 11:27:13 +0200
commit7109561524dc57b95fd3f9b61547268b9b6db8ed (patch)
treedf08f565b2c616b7e68fe35cd428a8c5ba3bfcb1 /mm
parentARM: 8124/1: don't enter kgdb when userspace executes a kgdb break instruction (diff)
parentARM: add comments to the early page table remap code (diff)
downloadlinux-7109561524dc57b95fd3f9b61547268b9b6db8ed.tar.xz
linux-7109561524dc57b95fd3f9b61547268b9b6db8ed.zip
Merge branches 'fixes' and 'misc' into for-next
Conflicts: arch/arm/kernel/iwmmxt.S arch/arm/mm/cache-l2x0.c arch/arm/mm/mmu.c
Diffstat (limited to 'mm')
-rw-r--r--mm/huge_memory.c57
-rw-r--r--mm/hugetlb.c71
-rw-r--r--mm/ksm.c1
-rw-r--r--mm/mempolicy.c46
-rw-r--r--mm/migrate.c2
-rw-r--r--mm/nommu.c2
-rw-r--r--mm/page_alloc.c40
-rw-r--r--mm/rmap.c12
-rw-r--r--mm/shmem.c59
-rw-r--r--mm/slab.c90
10 files changed, 273 insertions, 107 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index e60837dc785c..33514d88fef9 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -941,6 +941,37 @@ unlock:
spin_unlock(ptl);
}
+/*
+ * Save CONFIG_DEBUG_PAGEALLOC from faulting falsely on tail pages
+ * during copy_user_huge_page()'s copy_page_rep(): in the case when
+ * the source page gets split and a tail freed before copy completes.
+ * Called under pmd_lock of checked pmd, so safe from splitting itself.
+ */
+static void get_user_huge_page(struct page *page)
+{
+ if (IS_ENABLED(CONFIG_DEBUG_PAGEALLOC)) {
+ struct page *endpage = page + HPAGE_PMD_NR;
+
+ atomic_add(HPAGE_PMD_NR, &page->_count);
+ while (++page < endpage)
+ get_huge_page_tail(page);
+ } else {
+ get_page(page);
+ }
+}
+
+static void put_user_huge_page(struct page *page)
+{
+ if (IS_ENABLED(CONFIG_DEBUG_PAGEALLOC)) {
+ struct page *endpage = page + HPAGE_PMD_NR;
+
+ while (page < endpage)
+ put_page(page++);
+ } else {
+ put_page(page);
+ }
+}
+
static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long address,
@@ -1074,7 +1105,7 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
ret |= VM_FAULT_WRITE;
goto out_unlock;
}
- get_page(page);
+ get_user_huge_page(page);
spin_unlock(ptl);
alloc:
if (transparent_hugepage_enabled(vma) &&
@@ -1095,7 +1126,7 @@ alloc:
split_huge_page(page);
ret |= VM_FAULT_FALLBACK;
}
- put_page(page);
+ put_user_huge_page(page);
}
count_vm_event(THP_FAULT_FALLBACK);
goto out;
@@ -1105,7 +1136,7 @@ alloc:
put_page(new_page);
if (page) {
split_huge_page(page);
- put_page(page);
+ put_user_huge_page(page);
} else
split_huge_page_pmd(vma, address, pmd);
ret |= VM_FAULT_FALLBACK;
@@ -1127,7 +1158,7 @@ alloc:
spin_lock(ptl);
if (page)
- put_page(page);
+ put_user_huge_page(page);
if (unlikely(!pmd_same(*pmd, orig_pmd))) {
spin_unlock(ptl);
mem_cgroup_uncharge_page(new_page);
@@ -2392,8 +2423,6 @@ static void collapse_huge_page(struct mm_struct *mm,
pmd = mm_find_pmd(mm, address);
if (!pmd)
goto out;
- if (pmd_trans_huge(*pmd))
- goto out;
anon_vma_lock_write(vma->anon_vma);
@@ -2492,8 +2521,6 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
pmd = mm_find_pmd(mm, address);
if (!pmd)
goto out;
- if (pmd_trans_huge(*pmd))
- goto out;
memset(khugepaged_node_load, 0, sizeof(khugepaged_node_load));
pte = pte_offset_map_lock(mm, pmd, address, &ptl);
@@ -2846,12 +2873,22 @@ void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
static void split_huge_page_address(struct mm_struct *mm,
unsigned long address)
{
+ pgd_t *pgd;
+ pud_t *pud;
pmd_t *pmd;
VM_BUG_ON(!(address & ~HPAGE_PMD_MASK));
- pmd = mm_find_pmd(mm, address);
- if (!pmd)
+ pgd = pgd_offset(mm, address);
+ if (!pgd_present(*pgd))
+ return;
+
+ pud = pud_offset(pgd, address);
+ if (!pud_present(*pud))
+ return;
+
+ pmd = pmd_offset(pud, address);
+ if (!pmd_present(*pmd))
return;
/*
* Caller holds the mmap_sem write mode, so a huge pmd cannot
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 226910cb7c9b..2024bbd573d2 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2520,6 +2520,31 @@ static void set_huge_ptep_writable(struct vm_area_struct *vma,
update_mmu_cache(vma, address, ptep);
}
+static int is_hugetlb_entry_migration(pte_t pte)
+{
+ swp_entry_t swp;
+
+ if (huge_pte_none(pte) || pte_present(pte))
+ return 0;
+ swp = pte_to_swp_entry(pte);
+ if (non_swap_entry(swp) && is_migration_entry(swp))
+ return 1;
+ else
+ return 0;
+}
+
+static int is_hugetlb_entry_hwpoisoned(pte_t pte)
+{
+ swp_entry_t swp;
+
+ if (huge_pte_none(pte) || pte_present(pte))
+ return 0;
+ swp = pte_to_swp_entry(pte);
+ if (non_swap_entry(swp) && is_hwpoison_entry(swp))
+ return 1;
+ else
+ return 0;
+}
int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
struct vm_area_struct *vma)
@@ -2559,10 +2584,26 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
dst_ptl = huge_pte_lock(h, dst, dst_pte);
src_ptl = huge_pte_lockptr(h, src, src_pte);
spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
- if (!huge_pte_none(huge_ptep_get(src_pte))) {
+ entry = huge_ptep_get(src_pte);
+ if (huge_pte_none(entry)) { /* skip none entry */
+ ;
+ } else if (unlikely(is_hugetlb_entry_migration(entry) ||
+ is_hugetlb_entry_hwpoisoned(entry))) {
+ swp_entry_t swp_entry = pte_to_swp_entry(entry);
+
+ if (is_write_migration_entry(swp_entry) && cow) {
+ /*
+ * COW mappings require pages in both
+ * parent and child to be set to read.
+ */
+ make_migration_entry_read(&swp_entry);
+ entry = swp_entry_to_pte(swp_entry);
+ set_huge_pte_at(src, addr, src_pte, entry);
+ }
+ set_huge_pte_at(dst, addr, dst_pte, entry);
+ } else {
if (cow)
huge_ptep_set_wrprotect(src, addr, src_pte);
- entry = huge_ptep_get(src_pte);
ptepage = pte_page(entry);
get_page(ptepage);
page_dup_rmap(ptepage);
@@ -2578,32 +2619,6 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
return ret;
}
-static int is_hugetlb_entry_migration(pte_t pte)
-{
- swp_entry_t swp;
-
- if (huge_pte_none(pte) || pte_present(pte))
- return 0;
- swp = pte_to_swp_entry(pte);
- if (non_swap_entry(swp) && is_migration_entry(swp))
- return 1;
- else
- return 0;
-}
-
-static int is_hugetlb_entry_hwpoisoned(pte_t pte)
-{
- swp_entry_t swp;
-
- if (huge_pte_none(pte) || pte_present(pte))
- return 0;
- swp = pte_to_swp_entry(pte);
- if (non_swap_entry(swp) && is_hwpoison_entry(swp))
- return 1;
- else
- return 0;
-}
-
void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
unsigned long start, unsigned long end,
struct page *ref_page)
diff --git a/mm/ksm.c b/mm/ksm.c
index 68710e80994a..346ddc9e4c0d 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -945,7 +945,6 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
pmd = mm_find_pmd(mm, addr);
if (!pmd)
goto out;
- BUG_ON(pmd_trans_huge(*pmd));
mmun_start = addr;
mmun_end = addr + PAGE_SIZE;
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 284974230459..eb58de19f815 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -656,19 +656,18 @@ static unsigned long change_prot_numa(struct vm_area_struct *vma,
* @nodes and @flags,) it's isolated and queued to the pagelist which is
* passed via @private.)
*/
-static struct vm_area_struct *
+static int
queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end,
const nodemask_t *nodes, unsigned long flags, void *private)
{
- int err;
- struct vm_area_struct *first, *vma, *prev;
-
+ int err = 0;
+ struct vm_area_struct *vma, *prev;
- first = find_vma(mm, start);
- if (!first)
- return ERR_PTR(-EFAULT);
+ vma = find_vma(mm, start);
+ if (!vma)
+ return -EFAULT;
prev = NULL;
- for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) {
+ for (; vma && vma->vm_start < end; vma = vma->vm_next) {
unsigned long endvma = vma->vm_end;
if (endvma > end)
@@ -678,9 +677,9 @@ queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end,
if (!(flags & MPOL_MF_DISCONTIG_OK)) {
if (!vma->vm_next && vma->vm_end < end)
- return ERR_PTR(-EFAULT);
+ return -EFAULT;
if (prev && prev->vm_end < vma->vm_start)
- return ERR_PTR(-EFAULT);
+ return -EFAULT;
}
if (flags & MPOL_MF_LAZY) {
@@ -694,15 +693,13 @@ queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end,
err = queue_pages_pgd_range(vma, start, endvma, nodes,
flags, private);
- if (err) {
- first = ERR_PTR(err);
+ if (err)
break;
- }
}
next:
prev = vma;
}
- return first;
+ return err;
}
/*
@@ -1156,16 +1153,17 @@ out:
/*
* Allocate a new page for page migration based on vma policy.
- * Start assuming that page is mapped by vma pointed to by @private.
+ * Start by assuming the page is mapped by the same vma as contains @start.
* Search forward from there, if not. N.B., this assumes that the
* list of pages handed to migrate_pages()--which is how we get here--
* is in virtual address order.
*/
-static struct page *new_vma_page(struct page *page, unsigned long private, int **x)
+static struct page *new_page(struct page *page, unsigned long start, int **x)
{
- struct vm_area_struct *vma = (struct vm_area_struct *)private;
+ struct vm_area_struct *vma;
unsigned long uninitialized_var(address);
+ vma = find_vma(current->mm, start);
while (vma) {
address = page_address_in_vma(page, vma);
if (address != -EFAULT)
@@ -1195,7 +1193,7 @@ int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
return -ENOSYS;
}
-static struct page *new_vma_page(struct page *page, unsigned long private, int **x)
+static struct page *new_page(struct page *page, unsigned long start, int **x)
{
return NULL;
}
@@ -1205,7 +1203,6 @@ static long do_mbind(unsigned long start, unsigned long len,
unsigned short mode, unsigned short mode_flags,
nodemask_t *nmask, unsigned long flags)
{
- struct vm_area_struct *vma;
struct mm_struct *mm = current->mm;
struct mempolicy *new;
unsigned long end;
@@ -1271,11 +1268,9 @@ static long do_mbind(unsigned long start, unsigned long len,
if (err)
goto mpol_out;
- vma = queue_pages_range(mm, start, end, nmask,
+ err = queue_pages_range(mm, start, end, nmask,
flags | MPOL_MF_INVERT, &pagelist);
-
- err = PTR_ERR(vma); /* maybe ... */
- if (!IS_ERR(vma))
+ if (!err)
err = mbind_range(mm, start, end, new);
if (!err) {
@@ -1283,9 +1278,8 @@ static long do_mbind(unsigned long start, unsigned long len,
if (!list_empty(&pagelist)) {
WARN_ON_ONCE(flags & MPOL_MF_LAZY);
- nr_failed = migrate_pages(&pagelist, new_vma_page,
- NULL, (unsigned long)vma,
- MIGRATE_SYNC, MR_MEMPOLICY_MBIND);
+ nr_failed = migrate_pages(&pagelist, new_page, NULL,
+ start, MIGRATE_SYNC, MR_MEMPOLICY_MBIND);
if (nr_failed)
putback_movable_pages(&pagelist);
}
diff --git a/mm/migrate.c b/mm/migrate.c
index 63f0cd559999..9e0beaa91845 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -120,8 +120,6 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma,
pmd = mm_find_pmd(mm, addr);
if (!pmd)
goto out;
- if (pmd_trans_huge(*pmd))
- goto out;
ptep = pte_offset_map(pmd, addr);
diff --git a/mm/nommu.c b/mm/nommu.c
index b78e3a8f5ee7..4a852f6c5709 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -786,7 +786,7 @@ static void delete_vma_from_mm(struct vm_area_struct *vma)
for (i = 0; i < VMACACHE_SIZE; i++) {
/* if the vma is cached, invalidate the entire cache */
if (curr->vmacache[i] == vma) {
- vmacache_invalidate(curr->mm);
+ vmacache_invalidate(mm);
break;
}
}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4f59fa29eda8..20d17f8266fe 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -69,6 +69,7 @@
/* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */
static DEFINE_MUTEX(pcp_batch_high_lock);
+#define MIN_PERCPU_PAGELIST_FRACTION (8)
#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
DEFINE_PER_CPU(int, numa_node);
@@ -4145,7 +4146,7 @@ static void __meminit zone_init_free_lists(struct zone *zone)
memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
#endif
-static int __meminit zone_batchsize(struct zone *zone)
+static int zone_batchsize(struct zone *zone)
{
#ifdef CONFIG_MMU
int batch;
@@ -4261,8 +4262,8 @@ static void pageset_set_high(struct per_cpu_pageset *p,
pageset_update(&p->pcp, high, batch);
}
-static void __meminit pageset_set_high_and_batch(struct zone *zone,
- struct per_cpu_pageset *pcp)
+static void pageset_set_high_and_batch(struct zone *zone,
+ struct per_cpu_pageset *pcp)
{
if (percpu_pagelist_fraction)
pageset_set_high(pcp,
@@ -5881,23 +5882,38 @@ int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *length, loff_t *ppos)
{
struct zone *zone;
- unsigned int cpu;
+ int old_percpu_pagelist_fraction;
int ret;
+ mutex_lock(&pcp_batch_high_lock);
+ old_percpu_pagelist_fraction = percpu_pagelist_fraction;
+
ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
- if (!write || (ret < 0))
- return ret;
+ if (!write || ret < 0)
+ goto out;
+
+ /* Sanity checking to avoid pcp imbalance */
+ if (percpu_pagelist_fraction &&
+ percpu_pagelist_fraction < MIN_PERCPU_PAGELIST_FRACTION) {
+ percpu_pagelist_fraction = old_percpu_pagelist_fraction;
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* No change? */
+ if (percpu_pagelist_fraction == old_percpu_pagelist_fraction)
+ goto out;
- mutex_lock(&pcp_batch_high_lock);
for_each_populated_zone(zone) {
- unsigned long high;
- high = zone->managed_pages / percpu_pagelist_fraction;
+ unsigned int cpu;
+
for_each_possible_cpu(cpu)
- pageset_set_high(per_cpu_ptr(zone->pageset, cpu),
- high);
+ pageset_set_high_and_batch(zone,
+ per_cpu_ptr(zone->pageset, cpu));
}
+out:
mutex_unlock(&pcp_batch_high_lock);
- return 0;
+ return ret;
}
int hashdist = HASHDIST_DEFAULT;
diff --git a/mm/rmap.c b/mm/rmap.c
index bf05fc872ae8..b7e94ebbd09e 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -569,6 +569,7 @@ pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd = NULL;
+ pmd_t pmde;
pgd = pgd_offset(mm, address);
if (!pgd_present(*pgd))
@@ -579,7 +580,13 @@ pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
goto out;
pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd))
+ /*
+ * Some THP functions use the sequence pmdp_clear_flush(), set_pmd_at()
+ * without holding anon_vma lock for write. So when looking for a
+ * genuine pmde (in which to find pte), test present and !THP together.
+ */
+ pmde = ACCESS_ONCE(*pmd);
+ if (!pmd_present(pmde) || pmd_trans_huge(pmde))
pmd = NULL;
out:
return pmd;
@@ -615,9 +622,6 @@ pte_t *__page_check_address(struct page *page, struct mm_struct *mm,
if (!pmd)
return NULL;
- if (pmd_trans_huge(*pmd))
- return NULL;
-
pte = pte_offset_map(pmd, address);
/* Make a quick check before getting the lock */
if (!sync && !pte_present(*pte)) {
diff --git a/mm/shmem.c b/mm/shmem.c
index f484c276e994..8f419cff9e34 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -80,11 +80,12 @@ static struct vfsmount *shm_mnt;
#define SHORT_SYMLINK_LEN 128
/*
- * shmem_fallocate and shmem_writepage communicate via inode->i_private
- * (with i_mutex making sure that it has only one user at a time):
- * we would prefer not to enlarge the shmem inode just for that.
+ * shmem_fallocate communicates with shmem_fault or shmem_writepage via
+ * inode->i_private (with i_mutex making sure that it has only one user at
+ * a time): we would prefer not to enlarge the shmem inode just for that.
*/
struct shmem_falloc {
+ int mode; /* FALLOC_FL mode currently operating */
pgoff_t start; /* start of range currently being fallocated */
pgoff_t next; /* the next page offset to be fallocated */
pgoff_t nr_falloced; /* how many new pages have been fallocated */
@@ -759,6 +760,7 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc)
spin_lock(&inode->i_lock);
shmem_falloc = inode->i_private;
if (shmem_falloc &&
+ !shmem_falloc->mode &&
index >= shmem_falloc->start &&
index < shmem_falloc->next)
shmem_falloc->nr_unswapped++;
@@ -1233,6 +1235,44 @@ static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
int error;
int ret = VM_FAULT_LOCKED;
+ /*
+ * Trinity finds that probing a hole which tmpfs is punching can
+ * prevent the hole-punch from ever completing: which in turn
+ * locks writers out with its hold on i_mutex. So refrain from
+ * faulting pages into the hole while it's being punched, and
+ * wait on i_mutex to be released if vmf->flags permits.
+ */
+ if (unlikely(inode->i_private)) {
+ struct shmem_falloc *shmem_falloc;
+
+ spin_lock(&inode->i_lock);
+ shmem_falloc = inode->i_private;
+ if (!shmem_falloc ||
+ shmem_falloc->mode != FALLOC_FL_PUNCH_HOLE ||
+ vmf->pgoff < shmem_falloc->start ||
+ vmf->pgoff >= shmem_falloc->next)
+ shmem_falloc = NULL;
+ spin_unlock(&inode->i_lock);
+ /*
+ * i_lock has protected us from taking shmem_falloc seriously
+ * once return from shmem_fallocate() went back up that stack.
+ * i_lock does not serialize with i_mutex at all, but it does
+ * not matter if sometimes we wait unnecessarily, or sometimes
+ * miss out on waiting: we just need to make those cases rare.
+ */
+ if (shmem_falloc) {
+ if ((vmf->flags & FAULT_FLAG_ALLOW_RETRY) &&
+ !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
+ up_read(&vma->vm_mm->mmap_sem);
+ mutex_lock(&inode->i_mutex);
+ mutex_unlock(&inode->i_mutex);
+ return VM_FAULT_RETRY;
+ }
+ /* cond_resched? Leave that to GUP or return to user */
+ return VM_FAULT_NOPAGE;
+ }
+ }
+
error = shmem_getpage(inode, vmf->pgoff, &vmf->page, SGP_CACHE, &ret);
if (error)
return ((error == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS);
@@ -1724,20 +1764,31 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset,
pgoff_t start, index, end;
int error;
+ if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+ return -EOPNOTSUPP;
+
mutex_lock(&inode->i_mutex);
+ shmem_falloc.mode = mode & ~FALLOC_FL_KEEP_SIZE;
+
if (mode & FALLOC_FL_PUNCH_HOLE) {
struct address_space *mapping = file->f_mapping;
loff_t unmap_start = round_up(offset, PAGE_SIZE);
loff_t unmap_end = round_down(offset + len, PAGE_SIZE) - 1;
+ shmem_falloc.start = unmap_start >> PAGE_SHIFT;
+ shmem_falloc.next = (unmap_end + 1) >> PAGE_SHIFT;
+ spin_lock(&inode->i_lock);
+ inode->i_private = &shmem_falloc;
+ spin_unlock(&inode->i_lock);
+
if ((u64)unmap_end > (u64)unmap_start)
unmap_mapping_range(mapping, unmap_start,
1 + unmap_end - unmap_start, 0);
shmem_truncate_range(inode, offset, offset + len - 1);
/* No need to unmap again: hole-punching leaves COWed pages */
error = 0;
- goto out;
+ goto undone;
}
/* We need to check rlimit even when FALLOC_FL_KEEP_SIZE */
diff --git a/mm/slab.c b/mm/slab.c
index 9ca3b87edabc..3070b929a1bf 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -386,6 +386,39 @@ static void **dbg_userword(struct kmem_cache *cachep, void *objp)
#endif
+#define OBJECT_FREE (0)
+#define OBJECT_ACTIVE (1)
+
+#ifdef CONFIG_DEBUG_SLAB_LEAK
+
+static void set_obj_status(struct page *page, int idx, int val)
+{
+ int freelist_size;
+ char *status;
+ struct kmem_cache *cachep = page->slab_cache;
+
+ freelist_size = cachep->num * sizeof(freelist_idx_t);
+ status = (char *)page->freelist + freelist_size;
+ status[idx] = val;
+}
+
+static inline unsigned int get_obj_status(struct page *page, int idx)
+{
+ int freelist_size;
+ char *status;
+ struct kmem_cache *cachep = page->slab_cache;
+
+ freelist_size = cachep->num * sizeof(freelist_idx_t);
+ status = (char *)page->freelist + freelist_size;
+
+ return status[idx];
+}
+
+#else
+static inline void set_obj_status(struct page *page, int idx, int val) {}
+
+#endif
+
/*
* Do not go above this order unless 0 objects fit into the slab or
* overridden on the command line.
@@ -576,12 +609,30 @@ static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep)
return cachep->array[smp_processor_id()];
}
+static size_t calculate_freelist_size(int nr_objs, size_t align)
+{
+ size_t freelist_size;
+
+ freelist_size = nr_objs * sizeof(freelist_idx_t);
+ if (IS_ENABLED(CONFIG_DEBUG_SLAB_LEAK))
+ freelist_size += nr_objs * sizeof(char);
+
+ if (align)
+ freelist_size = ALIGN(freelist_size, align);
+
+ return freelist_size;
+}
+
static int calculate_nr_objs(size_t slab_size, size_t buffer_size,
size_t idx_size, size_t align)
{
int nr_objs;
+ size_t remained_size;
size_t freelist_size;
+ int extra_space = 0;
+ if (IS_ENABLED(CONFIG_DEBUG_SLAB_LEAK))
+ extra_space = sizeof(char);
/*
* Ignore padding for the initial guess. The padding
* is at most @align-1 bytes, and @buffer_size is at
@@ -590,14 +641,15 @@ static int calculate_nr_objs(size_t slab_size, size_t buffer_size,
* into the memory allocation when taking the padding
* into account.
*/
- nr_objs = slab_size / (buffer_size + idx_size);
+ nr_objs = slab_size / (buffer_size + idx_size + extra_space);
/*
* This calculated number will be either the right
* amount, or one greater than what we want.
*/
- freelist_size = slab_size - nr_objs * buffer_size;
- if (freelist_size < ALIGN(nr_objs * idx_size, align))
+ remained_size = slab_size - nr_objs * buffer_size;
+ freelist_size = calculate_freelist_size(nr_objs, align);
+ if (remained_size < freelist_size)
nr_objs--;
return nr_objs;
@@ -635,7 +687,7 @@ static void cache_estimate(unsigned long gfporder, size_t buffer_size,
} else {
nr_objs = calculate_nr_objs(slab_size, buffer_size,
sizeof(freelist_idx_t), align);
- mgmt_size = ALIGN(nr_objs * sizeof(freelist_idx_t), align);
+ mgmt_size = calculate_freelist_size(nr_objs, align);
}
*num = nr_objs;
*left_over = slab_size - nr_objs*buffer_size - mgmt_size;
@@ -2041,13 +2093,16 @@ static size_t calculate_slab_order(struct kmem_cache *cachep,
break;
if (flags & CFLGS_OFF_SLAB) {
+ size_t freelist_size_per_obj = sizeof(freelist_idx_t);
/*
* Max number of objs-per-slab for caches which
* use off-slab slabs. Needed to avoid a possible
* looping condition in cache_grow().
*/
+ if (IS_ENABLED(CONFIG_DEBUG_SLAB_LEAK))
+ freelist_size_per_obj += sizeof(char);
offslab_limit = size;
- offslab_limit /= sizeof(freelist_idx_t);
+ offslab_limit /= freelist_size_per_obj;
if (num > offslab_limit)
break;
@@ -2294,8 +2349,7 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
if (!cachep->num)
return -E2BIG;
- freelist_size =
- ALIGN(cachep->num * sizeof(freelist_idx_t), cachep->align);
+ freelist_size = calculate_freelist_size(cachep->num, cachep->align);
/*
* If the slab has been placed off-slab, and we have enough space then
@@ -2308,7 +2362,7 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
if (flags & CFLGS_OFF_SLAB) {
/* really off slab. No need for manual alignment */
- freelist_size = cachep->num * sizeof(freelist_idx_t);
+ freelist_size = calculate_freelist_size(cachep->num, 0);
#ifdef CONFIG_PAGE_POISONING
/* If we're going to use the generic kernel_map_pages()
@@ -2612,6 +2666,7 @@ static void cache_init_objs(struct kmem_cache *cachep,
if (cachep->ctor)
cachep->ctor(objp);
#endif
+ set_obj_status(page, i, OBJECT_FREE);
set_free_obj(page, i, i);
}
}
@@ -2820,6 +2875,7 @@ static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
BUG_ON(objnr >= cachep->num);
BUG_ON(objp != index_to_obj(cachep, page, objnr));
+ set_obj_status(page, objnr, OBJECT_FREE);
if (cachep->flags & SLAB_POISON) {
#ifdef CONFIG_DEBUG_PAGEALLOC
if ((cachep->size % PAGE_SIZE)==0 && OFF_SLAB(cachep)) {
@@ -2953,6 +3009,8 @@ static inline void cache_alloc_debugcheck_before(struct kmem_cache *cachep,
static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
gfp_t flags, void *objp, unsigned long caller)
{
+ struct page *page;
+
if (!objp)
return objp;
if (cachep->flags & SLAB_POISON) {
@@ -2983,6 +3041,9 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
*dbg_redzone1(cachep, objp) = RED_ACTIVE;
*dbg_redzone2(cachep, objp) = RED_ACTIVE;
}
+
+ page = virt_to_head_page(objp);
+ set_obj_status(page, obj_to_index(cachep, page, objp), OBJECT_ACTIVE);
objp += obj_offset(cachep);
if (cachep->ctor && cachep->flags & SLAB_POISON)
cachep->ctor(objp);
@@ -4219,21 +4280,12 @@ static void handle_slab(unsigned long *n, struct kmem_cache *c,
struct page *page)
{
void *p;
- int i, j;
+ int i;
if (n[0] == n[1])
return;
for (i = 0, p = page->s_mem; i < c->num; i++, p += c->size) {
- bool active = true;
-
- for (j = page->active; j < c->num; j++) {
- /* Skip freed item */
- if (get_free_obj(page, j) == i) {
- active = false;
- break;
- }
- }
- if (!active)
+ if (get_obj_status(page, i) != OBJECT_ACTIVE)
continue;
if (!add_caller(n, (unsigned long)*dbg_userword(c, p)))