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-rw-r--r--mm/page_alloc.c360
1 files changed, 298 insertions, 62 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d03c946d5566..a9649f4b261e 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -49,6 +49,7 @@
#include <linux/debugobjects.h>
#include <linux/kmemleak.h>
#include <linux/memory.h>
+#include <linux/compaction.h>
#include <trace/events/kmem.h>
#include <linux/ftrace_event.h>
@@ -56,6 +57,22 @@
#include <asm/div64.h>
#include "internal.h"
+#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
+DEFINE_PER_CPU(int, numa_node);
+EXPORT_PER_CPU_SYMBOL(numa_node);
+#endif
+
+#ifdef CONFIG_HAVE_MEMORYLESS_NODES
+/*
+ * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
+ * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
+ * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
+ * defined in <linux/topology.h>.
+ */
+DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */
+EXPORT_PER_CPU_SYMBOL(_numa_mem_);
+#endif
+
/*
* Array of node states.
*/
@@ -475,6 +492,8 @@ static inline void __free_one_page(struct page *page,
int migratetype)
{
unsigned long page_idx;
+ unsigned long combined_idx;
+ struct page *buddy;
if (unlikely(PageCompound(page)))
if (unlikely(destroy_compound_page(page, order)))
@@ -488,9 +507,6 @@ static inline void __free_one_page(struct page *page,
VM_BUG_ON(bad_range(zone, page));
while (order < MAX_ORDER-1) {
- unsigned long combined_idx;
- struct page *buddy;
-
buddy = __page_find_buddy(page, page_idx, order);
if (!page_is_buddy(page, buddy, order))
break;
@@ -505,8 +521,29 @@ static inline void __free_one_page(struct page *page,
order++;
}
set_page_order(page, order);
- list_add(&page->lru,
- &zone->free_area[order].free_list[migratetype]);
+
+ /*
+ * 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
+ * that pages are being freed that will coalesce soon. In case,
+ * that is happening, add the free page to the tail of the list
+ * so it's less likely to be used soon and more likely to be merged
+ * as a higher order page
+ */
+ if ((order < MAX_ORDER-1) && pfn_valid_within(page_to_pfn(buddy))) {
+ struct page *higher_page, *higher_buddy;
+ combined_idx = __find_combined_index(page_idx, order);
+ higher_page = page + combined_idx - page_idx;
+ higher_buddy = __page_find_buddy(higher_page, combined_idx, order + 1);
+ if (page_is_buddy(higher_page, higher_buddy, order + 1)) {
+ list_add_tail(&page->lru,
+ &zone->free_area[order].free_list[migratetype]);
+ goto out;
+ }
+ }
+
+ list_add(&page->lru, &zone->free_area[order].free_list[migratetype]);
+out:
zone->free_area[order].nr_free++;
}
@@ -599,20 +636,23 @@ static void free_one_page(struct zone *zone, struct page *page, int order,
spin_unlock(&zone->lock);
}
-static void __free_pages_ok(struct page *page, unsigned int order)
+static bool free_pages_prepare(struct page *page, unsigned int order)
{
- unsigned long flags;
int i;
int bad = 0;
- int wasMlocked = __TestClearPageMlocked(page);
trace_mm_page_free_direct(page, order);
kmemcheck_free_shadow(page, order);
- for (i = 0 ; i < (1 << order) ; ++i)
- bad += free_pages_check(page + i);
+ for (i = 0; i < (1 << order); i++) {
+ struct page *pg = page + i;
+
+ if (PageAnon(pg))
+ pg->mapping = NULL;
+ bad += free_pages_check(pg);
+ }
if (bad)
- return;
+ return false;
if (!PageHighMem(page)) {
debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order);
@@ -622,6 +662,17 @@ static void __free_pages_ok(struct page *page, unsigned int order)
arch_free_page(page, order);
kernel_map_pages(page, 1 << order, 0);
+ return true;
+}
+
+static void __free_pages_ok(struct page *page, unsigned int order)
+{
+ unsigned long flags;
+ int wasMlocked = __TestClearPageMlocked(page);
+
+ if (!free_pages_prepare(page, order))
+ return;
+
local_irq_save(flags);
if (unlikely(wasMlocked))
free_page_mlock(page);
@@ -1107,21 +1158,9 @@ void free_hot_cold_page(struct page *page, int cold)
int migratetype;
int wasMlocked = __TestClearPageMlocked(page);
- trace_mm_page_free_direct(page, 0);
- kmemcheck_free_shadow(page, 0);
-
- if (PageAnon(page))
- page->mapping = NULL;
- if (free_pages_check(page))
+ if (!free_pages_prepare(page, 0))
return;
- if (!PageHighMem(page)) {
- debug_check_no_locks_freed(page_address(page), PAGE_SIZE);
- debug_check_no_obj_freed(page_address(page), PAGE_SIZE);
- }
- arch_free_page(page, 0);
- kernel_map_pages(page, 1, 0);
-
migratetype = get_pageblock_migratetype(page);
set_page_private(page, migratetype);
local_irq_save(flags);
@@ -1188,6 +1227,51 @@ void split_page(struct page *page, unsigned int order)
}
/*
+ * Similar to split_page except the page is already free. As this is only
+ * being used for migration, the migratetype of the block also changes.
+ * As this is called with interrupts disabled, the caller is responsible
+ * for calling arch_alloc_page() and kernel_map_page() after interrupts
+ * are enabled.
+ *
+ * Note: this is probably too low level an operation for use in drivers.
+ * Please consult with lkml before using this in your driver.
+ */
+int split_free_page(struct page *page)
+{
+ unsigned int order;
+ unsigned long watermark;
+ struct zone *zone;
+
+ BUG_ON(!PageBuddy(page));
+
+ zone = page_zone(page);
+ order = page_order(page);
+
+ /* Obey watermarks as if the page was being allocated */
+ watermark = low_wmark_pages(zone) + (1 << order);
+ if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
+ return 0;
+
+ /* Remove page from free list */
+ list_del(&page->lru);
+ zone->free_area[order].nr_free--;
+ rmv_page_order(page);
+ __mod_zone_page_state(zone, NR_FREE_PAGES, -(1UL << order));
+
+ /* Split into individual pages */
+ set_page_refcounted(page);
+ split_page(page, order);
+
+ if (order >= pageblock_order - 1) {
+ struct page *endpage = page + (1 << order) - 1;
+ for (; page < endpage; page += pageblock_nr_pages)
+ set_pageblock_migratetype(page, MIGRATE_MOVABLE);
+ }
+
+ return 1 << order;
+}
+
+/*
* Really, prep_compound_page() should be called from __rmqueue_bulk(). But
* we cheat by calling it from here, in the order > 0 path. Saves a branch
* or two.
@@ -1654,7 +1738,7 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
struct page *page;
/* Acquire the OOM killer lock for the zones in zonelist */
- if (!try_set_zone_oom(zonelist, gfp_mask)) {
+ if (!try_set_zonelist_oom(zonelist, gfp_mask)) {
schedule_timeout_uninterruptible(1);
return NULL;
}
@@ -1675,6 +1759,9 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
/* The OOM killer will not help higher order allocs */
if (order > PAGE_ALLOC_COSTLY_ORDER)
goto out;
+ /* The OOM killer does not needlessly kill tasks for lowmem */
+ if (high_zoneidx < ZONE_NORMAL)
+ goto out;
/*
* GFP_THISNODE contains __GFP_NORETRY and we never hit this.
* Sanity check for bare calls of __GFP_THISNODE, not real OOM.
@@ -1693,6 +1780,62 @@ out:
return page;
}
+#ifdef CONFIG_COMPACTION
+/* Try memory compaction for high-order allocations before reclaim */
+static struct page *
+__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, enum zone_type high_zoneidx,
+ nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
+ int migratetype, unsigned long *did_some_progress)
+{
+ struct page *page;
+
+ if (!order || compaction_deferred(preferred_zone))
+ return NULL;
+
+ *did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
+ nodemask);
+ if (*did_some_progress != COMPACT_SKIPPED) {
+
+ /* Page migration frees to the PCP lists but we want merging */
+ drain_pages(get_cpu());
+ put_cpu();
+
+ page = get_page_from_freelist(gfp_mask, nodemask,
+ order, zonelist, high_zoneidx,
+ alloc_flags, preferred_zone,
+ migratetype);
+ if (page) {
+ preferred_zone->compact_considered = 0;
+ preferred_zone->compact_defer_shift = 0;
+ count_vm_event(COMPACTSUCCESS);
+ return page;
+ }
+
+ /*
+ * It's bad if compaction run occurs and fails.
+ * The most likely reason is that pages exist,
+ * but not enough to satisfy watermarks.
+ */
+ count_vm_event(COMPACTFAIL);
+ defer_compaction(preferred_zone);
+
+ cond_resched();
+ }
+
+ return NULL;
+}
+#else
+static inline struct page *
+__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, enum zone_type high_zoneidx,
+ nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
+ int migratetype, unsigned long *did_some_progress)
+{
+ return NULL;
+}
+#endif /* CONFIG_COMPACTION */
+
/* The really slow allocator path where we enter direct reclaim */
static inline struct page *
__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
@@ -1879,6 +2022,15 @@ rebalance:
if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
goto nopage;
+ /* Try direct compaction */
+ page = __alloc_pages_direct_compact(gfp_mask, order,
+ zonelist, high_zoneidx,
+ nodemask,
+ alloc_flags, preferred_zone,
+ migratetype, &did_some_progress);
+ if (page)
+ goto got_pg;
+
/* Try direct reclaim and then allocating */
page = __alloc_pages_direct_reclaim(gfp_mask, order,
zonelist, high_zoneidx,
@@ -1903,15 +2055,23 @@ rebalance:
if (page)
goto got_pg;
- /*
- * The OOM killer does not trigger for high-order
- * ~__GFP_NOFAIL allocations so if no progress is being
- * made, there are no other options and retrying is
- * unlikely to help.
- */
- if (order > PAGE_ALLOC_COSTLY_ORDER &&
- !(gfp_mask & __GFP_NOFAIL))
- goto nopage;
+ if (!(gfp_mask & __GFP_NOFAIL)) {
+ /*
+ * The oom killer is not called for high-order
+ * allocations that may fail, so if no progress
+ * is being made, there are no other options and
+ * retrying is unlikely to help.
+ */
+ if (order > PAGE_ALLOC_COSTLY_ORDER)
+ goto nopage;
+ /*
+ * The oom killer is not called for lowmem
+ * allocations to prevent needlessly killing
+ * innocent tasks.
+ */
+ if (high_zoneidx < ZONE_NORMAL)
+ goto nopage;
+ }
goto restart;
}
@@ -1970,10 +2130,13 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
if (unlikely(!zonelist->_zonerefs->zone))
return NULL;
+ get_mems_allowed();
/* The preferred zone is used for statistics later */
first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone);
- if (!preferred_zone)
+ if (!preferred_zone) {
+ put_mems_allowed();
return NULL;
+ }
/* First allocation attempt */
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
@@ -1983,6 +2146,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
page = __alloc_pages_slowpath(gfp_mask, order,
zonelist, high_zoneidx, nodemask,
preferred_zone, migratetype);
+ put_mems_allowed();
trace_mm_page_alloc(page, order, gfp_mask, migratetype);
return page;
@@ -2434,8 +2598,11 @@ int numa_zonelist_order_handler(ctl_table *table, int write,
strncpy((char*)table->data, saved_string,
NUMA_ZONELIST_ORDER_LEN);
user_zonelist_order = oldval;
- } else if (oldval != user_zonelist_order)
- build_all_zonelists();
+ } else if (oldval != user_zonelist_order) {
+ mutex_lock(&zonelists_mutex);
+ build_all_zonelists(NULL);
+ mutex_unlock(&zonelists_mutex);
+ }
}
out:
mutex_unlock(&zl_order_mutex);
@@ -2579,10 +2746,10 @@ static int default_zonelist_order(void)
struct zone *z;
int average_size;
/*
- * ZONE_DMA and ZONE_DMA32 can be very small area in the sytem.
+ * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
* If they are really small and used heavily, the system can fall
* into OOM very easily.
- * This function detect ZONE_DMA/DMA32 size and confgigures zone order.
+ * This function detect ZONE_DMA/DMA32 size and configures zone order.
*/
/* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
low_kmem_size = 0;
@@ -2594,6 +2761,15 @@ static int default_zonelist_order(void)
if (zone_type < ZONE_NORMAL)
low_kmem_size += z->present_pages;
total_size += z->present_pages;
+ } else if (zone_type == ZONE_NORMAL) {
+ /*
+ * If any node has only lowmem, then node order
+ * is preferred to allow kernel allocations
+ * locally; otherwise, they can easily infringe
+ * on other nodes when there is an abundance of
+ * lowmem available to allocate from.
+ */
+ return ZONELIST_ORDER_NODE;
}
}
}
@@ -2707,6 +2883,24 @@ static void build_zonelist_cache(pg_data_t *pgdat)
zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
}
+#ifdef CONFIG_HAVE_MEMORYLESS_NODES
+/*
+ * Return node id of node used for "local" allocations.
+ * I.e., first node id of first zone in arg node's generic zonelist.
+ * Used for initializing percpu 'numa_mem', which is used primarily
+ * for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
+ */
+int local_memory_node(int node)
+{
+ struct zone *zone;
+
+ (void)first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
+ gfp_zone(GFP_KERNEL),
+ NULL,
+ &zone);
+ return zone->node;
+}
+#endif
#else /* CONFIG_NUMA */
@@ -2776,9 +2970,16 @@ static void build_zonelist_cache(pg_data_t *pgdat)
*/
static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
+static void setup_zone_pageset(struct zone *zone);
+
+/*
+ * Global mutex to protect against size modification of zonelists
+ * as well as to serialize pageset setup for the new populated zone.
+ */
+DEFINE_MUTEX(zonelists_mutex);
/* return values int ....just for stop_machine() */
-static int __build_all_zonelists(void *dummy)
+static __init_refok int __build_all_zonelists(void *data)
{
int nid;
int cpu;
@@ -2793,6 +2994,14 @@ static int __build_all_zonelists(void *dummy)
build_zonelist_cache(pgdat);
}
+#ifdef CONFIG_MEMORY_HOTPLUG
+ /* Setup real pagesets for the new zone */
+ if (data) {
+ struct zone *zone = data;
+ setup_zone_pageset(zone);
+ }
+#endif
+
/*
* Initialize the boot_pagesets that are going to be used
* for bootstrapping processors. The real pagesets for
@@ -2806,13 +3015,31 @@ static int __build_all_zonelists(void *dummy)
* needs the percpu allocator in order to allocate its pagesets
* (a chicken-egg dilemma).
*/
- for_each_possible_cpu(cpu)
+ for_each_possible_cpu(cpu) {
setup_pageset(&per_cpu(boot_pageset, cpu), 0);
+#ifdef CONFIG_HAVE_MEMORYLESS_NODES
+ /*
+ * We now know the "local memory node" for each node--
+ * i.e., the node of the first zone in the generic zonelist.
+ * Set up numa_mem percpu variable for on-line cpus. During
+ * boot, only the boot cpu should be on-line; we'll init the
+ * secondary cpus' numa_mem as they come on-line. During
+ * node/memory hotplug, we'll fixup all on-line cpus.
+ */
+ if (cpu_online(cpu))
+ set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
+#endif
+ }
+
return 0;
}
-void build_all_zonelists(void)
+/*
+ * Called with zonelists_mutex held always
+ * unless system_state == SYSTEM_BOOTING.
+ */
+void build_all_zonelists(void *data)
{
set_zonelist_order();
@@ -2823,7 +3050,7 @@ void build_all_zonelists(void)
} else {
/* we have to stop all cpus to guarantee there is no user
of zonelist */
- stop_machine(__build_all_zonelists, NULL, NULL);
+ stop_machine(__build_all_zonelists, data, NULL);
/* cpuset refresh routine should be here */
}
vm_total_pages = nr_free_pagecache_pages();
@@ -3146,31 +3373,34 @@ static void setup_pagelist_highmark(struct per_cpu_pageset *p,
pcp->batch = PAGE_SHIFT * 8;
}
+static __meminit void setup_zone_pageset(struct zone *zone)
+{
+ int cpu;
+
+ zone->pageset = alloc_percpu(struct per_cpu_pageset);
+
+ for_each_possible_cpu(cpu) {
+ struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
+
+ setup_pageset(pcp, zone_batchsize(zone));
+
+ if (percpu_pagelist_fraction)
+ setup_pagelist_highmark(pcp,
+ (zone->present_pages /
+ percpu_pagelist_fraction));
+ }
+}
+
/*
* Allocate per cpu pagesets and initialize them.
* Before this call only boot pagesets were available.
- * Boot pagesets will no longer be used by this processorr
- * after setup_per_cpu_pageset().
*/
void __init setup_per_cpu_pageset(void)
{
struct zone *zone;
- int cpu;
-
- for_each_populated_zone(zone) {
- zone->pageset = alloc_percpu(struct per_cpu_pageset);
- for_each_possible_cpu(cpu) {
- struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
-
- setup_pageset(pcp, zone_batchsize(zone));
-
- if (percpu_pagelist_fraction)
- setup_pagelist_highmark(pcp,
- (zone->present_pages /
- percpu_pagelist_fraction));
- }
- }
+ for_each_populated_zone(zone)
+ setup_zone_pageset(zone);
}
static noinline __init_refok
@@ -3415,6 +3645,9 @@ void * __init __alloc_memory_core_early(int nid, u64 size, u64 align,
int i;
void *ptr;
+ if (limit > get_max_mapped())
+ limit = get_max_mapped();
+
/* need to go over early_node_map to find out good range for node */
for_each_active_range_index_in_nid(i, nid) {
u64 addr;
@@ -3440,6 +3673,11 @@ void * __init __alloc_memory_core_early(int nid, u64 size, u64 align,
ptr = phys_to_virt(addr);
memset(ptr, 0, size);
reserve_early_without_check(addr, addr + size, "BOOTMEM");
+ /*
+ * The min_count is set to 0 so that bootmem allocated blocks
+ * are never reported as leaks.
+ */
+ kmemleak_alloc(ptr, size, 0, 0);
return ptr;
}
@@ -3862,8 +4100,6 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
zone_seqlock_init(zone);
zone->zone_pgdat = pgdat;
- zone->prev_priority = DEF_PRIORITY;
-
zone_pcp_init(zone);
for_each_lru(l) {
INIT_LIST_HEAD(&zone->lru[l].list);