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-rw-r--r--Documentation/cgroups/memory.txt1
-rw-r--r--fs/buffer.c34
-rw-r--r--fs/xfs/xfs_aops.c12
-rw-r--r--include/linux/memcontrol.h1
-rw-r--r--include/linux/mm.h6
-rw-r--r--include/linux/pagemap.h3
-rw-r--r--mm/filemap.c31
-rw-r--r--mm/memcontrol.c24
-rw-r--r--mm/page-writeback.c50
-rw-r--r--mm/rmap.c2
-rw-r--r--mm/truncate.c14
-rw-r--r--mm/vmscan.c17
12 files changed, 156 insertions, 39 deletions
diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
index f456b4315e86..ff71e16cc752 100644
--- a/Documentation/cgroups/memory.txt
+++ b/Documentation/cgroups/memory.txt
@@ -493,6 +493,7 @@ pgpgin - # of charging events to the memory cgroup. The charging
pgpgout - # of uncharging events to the memory cgroup. The uncharging
event happens each time a page is unaccounted from the cgroup.
swap - # of bytes of swap usage
+dirty - # of bytes that are waiting to get written back to the disk.
writeback - # of bytes of file/anon cache that are queued for syncing to
disk.
inactive_anon - # of bytes of anonymous and swap cache memory on inactive
diff --git a/fs/buffer.c b/fs/buffer.c
index f21327d1f673..23b640d5d6e9 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -623,21 +623,22 @@ EXPORT_SYMBOL(mark_buffer_dirty_inode);
*
* If warn is true, then emit a warning if the page is not uptodate and has
* not been truncated.
+ *
+ * The caller must hold mem_cgroup_begin_page_stat() lock.
*/
-static void __set_page_dirty(struct page *page,
- struct address_space *mapping, int warn)
+static void __set_page_dirty(struct page *page, struct address_space *mapping,
+ struct mem_cgroup *memcg, int warn)
{
unsigned long flags;
spin_lock_irqsave(&mapping->tree_lock, flags);
if (page->mapping) { /* Race with truncate? */
WARN_ON_ONCE(warn && !PageUptodate(page));
- account_page_dirtied(page, mapping);
+ account_page_dirtied(page, mapping, memcg);
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
spin_unlock_irqrestore(&mapping->tree_lock, flags);
- __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
}
/*
@@ -668,6 +669,7 @@ static void __set_page_dirty(struct page *page,
int __set_page_dirty_buffers(struct page *page)
{
int newly_dirty;
+ struct mem_cgroup *memcg;
struct address_space *mapping = page_mapping(page);
if (unlikely(!mapping))
@@ -683,11 +685,22 @@ int __set_page_dirty_buffers(struct page *page)
bh = bh->b_this_page;
} while (bh != head);
}
+ /*
+ * Use mem_group_begin_page_stat() to keep PageDirty synchronized with
+ * per-memcg dirty page counters.
+ */
+ memcg = mem_cgroup_begin_page_stat(page);
newly_dirty = !TestSetPageDirty(page);
spin_unlock(&mapping->private_lock);
if (newly_dirty)
- __set_page_dirty(page, mapping, 1);
+ __set_page_dirty(page, mapping, memcg, 1);
+
+ mem_cgroup_end_page_stat(memcg);
+
+ if (newly_dirty)
+ __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
+
return newly_dirty;
}
EXPORT_SYMBOL(__set_page_dirty_buffers);
@@ -1158,11 +1171,18 @@ void mark_buffer_dirty(struct buffer_head *bh)
if (!test_set_buffer_dirty(bh)) {
struct page *page = bh->b_page;
+ struct address_space *mapping = NULL;
+ struct mem_cgroup *memcg;
+
+ memcg = mem_cgroup_begin_page_stat(page);
if (!TestSetPageDirty(page)) {
- struct address_space *mapping = page_mapping(page);
+ mapping = page_mapping(page);
if (mapping)
- __set_page_dirty(page, mapping, 0);
+ __set_page_dirty(page, mapping, memcg, 0);
}
+ mem_cgroup_end_page_stat(memcg);
+ if (mapping)
+ __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
}
}
EXPORT_SYMBOL(mark_buffer_dirty);
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 095f94c2d8b5..e5099f268032 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -1873,6 +1873,7 @@ xfs_vm_set_page_dirty(
loff_t end_offset;
loff_t offset;
int newly_dirty;
+ struct mem_cgroup *memcg;
if (unlikely(!mapping))
return !TestSetPageDirty(page);
@@ -1892,6 +1893,11 @@ xfs_vm_set_page_dirty(
offset += 1 << inode->i_blkbits;
} while (bh != head);
}
+ /*
+ * Use mem_group_begin_page_stat() to keep PageDirty synchronized with
+ * per-memcg dirty page counters.
+ */
+ memcg = mem_cgroup_begin_page_stat(page);
newly_dirty = !TestSetPageDirty(page);
spin_unlock(&mapping->private_lock);
@@ -1902,13 +1908,15 @@ xfs_vm_set_page_dirty(
spin_lock_irqsave(&mapping->tree_lock, flags);
if (page->mapping) { /* Race with truncate? */
WARN_ON_ONCE(!PageUptodate(page));
- account_page_dirtied(page, mapping);
+ account_page_dirtied(page, mapping, memcg);
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
spin_unlock_irqrestore(&mapping->tree_lock, flags);
- __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
}
+ mem_cgroup_end_page_stat(memcg);
+ if (newly_dirty)
+ __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
return newly_dirty;
}
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 72dff5fb0d0c..5fe6411b5e54 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -41,6 +41,7 @@ enum mem_cgroup_stat_index {
MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */
MEM_CGROUP_STAT_RSS_HUGE, /* # of pages charged as anon huge */
MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */
+ MEM_CGROUP_STAT_DIRTY, /* # of dirty pages in page cache */
MEM_CGROUP_STAT_WRITEBACK, /* # of pages under writeback */
MEM_CGROUP_STAT_SWAP, /* # of pages, swapped out */
MEM_CGROUP_STAT_NSTATS,
diff --git a/include/linux/mm.h b/include/linux/mm.h
index a83cf3a6f78e..f48d979ced4b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1211,8 +1211,10 @@ int __set_page_dirty_nobuffers(struct page *page);
int __set_page_dirty_no_writeback(struct page *page);
int redirty_page_for_writepage(struct writeback_control *wbc,
struct page *page);
-void account_page_dirtied(struct page *page, struct address_space *mapping);
-void account_page_cleaned(struct page *page, struct address_space *mapping);
+void account_page_dirtied(struct page *page, struct address_space *mapping,
+ struct mem_cgroup *memcg);
+void account_page_cleaned(struct page *page, struct address_space *mapping,
+ struct mem_cgroup *memcg);
int set_page_dirty(struct page *page);
int set_page_dirty_lock(struct page *page);
void cancel_dirty_page(struct page *page);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 4b3736f7065c..fb0814ca65c7 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -651,7 +651,8 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
pgoff_t index, gfp_t gfp_mask);
extern void delete_from_page_cache(struct page *page);
-extern void __delete_from_page_cache(struct page *page, void *shadow);
+extern void __delete_from_page_cache(struct page *page, void *shadow,
+ struct mem_cgroup *memcg);
int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask);
/*
diff --git a/mm/filemap.c b/mm/filemap.c
index 6bf5e42d560a..7b1443dc3ad0 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -100,6 +100,7 @@
* ->tree_lock (page_remove_rmap->set_page_dirty)
* bdi.wb->list_lock (page_remove_rmap->set_page_dirty)
* ->inode->i_lock (page_remove_rmap->set_page_dirty)
+ * ->memcg->move_lock (page_remove_rmap->mem_cgroup_begin_page_stat)
* bdi.wb->list_lock (zap_pte_range->set_page_dirty)
* ->inode->i_lock (zap_pte_range->set_page_dirty)
* ->private_lock (zap_pte_range->__set_page_dirty_buffers)
@@ -174,9 +175,11 @@ static void page_cache_tree_delete(struct address_space *mapping,
/*
* Delete a page from the page cache and free it. Caller has to make
* sure the page is locked and that nobody else uses it - or that usage
- * is safe. The caller must hold the mapping's tree_lock.
+ * is safe. The caller must hold the mapping's tree_lock and
+ * mem_cgroup_begin_page_stat().
*/
-void __delete_from_page_cache(struct page *page, void *shadow)
+void __delete_from_page_cache(struct page *page, void *shadow,
+ struct mem_cgroup *memcg)
{
struct address_space *mapping = page->mapping;
@@ -210,7 +213,7 @@ void __delete_from_page_cache(struct page *page, void *shadow)
* anyway will be cleared before returning page into buddy allocator.
*/
if (WARN_ON_ONCE(PageDirty(page)))
- account_page_cleaned(page, mapping);
+ account_page_cleaned(page, mapping, memcg);
}
/**
@@ -224,14 +227,20 @@ void __delete_from_page_cache(struct page *page, void *shadow)
void delete_from_page_cache(struct page *page)
{
struct address_space *mapping = page->mapping;
+ struct mem_cgroup *memcg;
+ unsigned long flags;
+
void (*freepage)(struct page *);
BUG_ON(!PageLocked(page));
freepage = mapping->a_ops->freepage;
- spin_lock_irq(&mapping->tree_lock);
- __delete_from_page_cache(page, NULL);
- spin_unlock_irq(&mapping->tree_lock);
+
+ memcg = mem_cgroup_begin_page_stat(page);
+ spin_lock_irqsave(&mapping->tree_lock, flags);
+ __delete_from_page_cache(page, NULL, memcg);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
if (freepage)
freepage(page);
@@ -470,6 +479,8 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
if (!error) {
struct address_space *mapping = old->mapping;
void (*freepage)(struct page *);
+ struct mem_cgroup *memcg;
+ unsigned long flags;
pgoff_t offset = old->index;
freepage = mapping->a_ops->freepage;
@@ -478,15 +489,17 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
new->mapping = mapping;
new->index = offset;
- spin_lock_irq(&mapping->tree_lock);
- __delete_from_page_cache(old, NULL);
+ memcg = mem_cgroup_begin_page_stat(old);
+ spin_lock_irqsave(&mapping->tree_lock, flags);
+ __delete_from_page_cache(old, NULL, memcg);
error = radix_tree_insert(&mapping->page_tree, offset, new);
BUG_ON(error);
mapping->nrpages++;
__inc_zone_page_state(new, NR_FILE_PAGES);
if (PageSwapBacked(new))
__inc_zone_page_state(new, NR_SHMEM);
- spin_unlock_irq(&mapping->tree_lock);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
mem_cgroup_migrate(old, new, true);
radix_tree_preload_end();
if (freepage)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 14c2f2017e37..c23c1a3e8e16 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -90,6 +90,7 @@ static const char * const mem_cgroup_stat_names[] = {
"rss",
"rss_huge",
"mapped_file",
+ "dirty",
"writeback",
"swap",
};
@@ -2011,6 +2012,7 @@ again:
return memcg;
}
+EXPORT_SYMBOL(mem_cgroup_begin_page_stat);
/**
* mem_cgroup_end_page_stat - finish a page state statistics transaction
@@ -2029,6 +2031,7 @@ void mem_cgroup_end_page_stat(struct mem_cgroup *memcg)
rcu_read_unlock();
}
+EXPORT_SYMBOL(mem_cgroup_end_page_stat);
/**
* mem_cgroup_update_page_stat - update page state statistics
@@ -4746,6 +4749,7 @@ static int mem_cgroup_move_account(struct page *page,
{
unsigned long flags;
int ret;
+ bool anon;
VM_BUG_ON(from == to);
VM_BUG_ON_PAGE(PageLRU(page), page);
@@ -4771,15 +4775,33 @@ static int mem_cgroup_move_account(struct page *page,
if (page->mem_cgroup != from)
goto out_unlock;
+ anon = PageAnon(page);
+
spin_lock_irqsave(&from->move_lock, flags);
- if (!PageAnon(page) && page_mapped(page)) {
+ if (!anon && page_mapped(page)) {
__this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED],
nr_pages);
__this_cpu_add(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED],
nr_pages);
}
+ /*
+ * move_lock grabbed above and caller set from->moving_account, so
+ * mem_cgroup_update_page_stat() will serialize updates to PageDirty.
+ * So mapping should be stable for dirty pages.
+ */
+ if (!anon && PageDirty(page)) {
+ struct address_space *mapping = page_mapping(page);
+
+ if (mapping_cap_account_dirty(mapping)) {
+ __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_DIRTY],
+ nr_pages);
+ __this_cpu_add(to->stat->count[MEM_CGROUP_STAT_DIRTY],
+ nr_pages);
+ }
+ }
+
if (PageWriteback(page)) {
__this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_WRITEBACK],
nr_pages);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 227b867598e1..bdeecad00489 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2090,15 +2090,20 @@ int __set_page_dirty_no_writeback(struct page *page)
/*
* Helper function for set_page_dirty family.
+ *
+ * Caller must hold mem_cgroup_begin_page_stat().
+ *
* NOTE: This relies on being atomic wrt interrupts.
*/
-void account_page_dirtied(struct page *page, struct address_space *mapping)
+void account_page_dirtied(struct page *page, struct address_space *mapping,
+ struct mem_cgroup *memcg)
{
trace_writeback_dirty_page(page, mapping);
if (mapping_cap_account_dirty(mapping)) {
struct backing_dev_info *bdi = inode_to_bdi(mapping->host);
+ mem_cgroup_inc_page_stat(memcg, MEM_CGROUP_STAT_DIRTY);
__inc_zone_page_state(page, NR_FILE_DIRTY);
__inc_zone_page_state(page, NR_DIRTIED);
__inc_bdi_stat(bdi, BDI_RECLAIMABLE);
@@ -2112,10 +2117,14 @@ EXPORT_SYMBOL(account_page_dirtied);
/*
* Helper function for deaccounting dirty page without writeback.
+ *
+ * Caller must hold mem_cgroup_begin_page_stat().
*/
-void account_page_cleaned(struct page *page, struct address_space *mapping)
+void account_page_cleaned(struct page *page, struct address_space *mapping,
+ struct mem_cgroup *memcg)
{
if (mapping_cap_account_dirty(mapping)) {
+ mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_DIRTY);
dec_zone_page_state(page, NR_FILE_DIRTY);
dec_bdi_stat(inode_to_bdi(mapping->host), BDI_RECLAIMABLE);
task_io_account_cancelled_write(PAGE_CACHE_SIZE);
@@ -2136,26 +2145,34 @@ void account_page_cleaned(struct page *page, struct address_space *mapping)
*/
int __set_page_dirty_nobuffers(struct page *page)
{
+ struct mem_cgroup *memcg;
+
+ memcg = mem_cgroup_begin_page_stat(page);
if (!TestSetPageDirty(page)) {
struct address_space *mapping = page_mapping(page);
unsigned long flags;
- if (!mapping)
+ if (!mapping) {
+ mem_cgroup_end_page_stat(memcg);
return 1;
+ }
spin_lock_irqsave(&mapping->tree_lock, flags);
BUG_ON(page_mapping(page) != mapping);
WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
- account_page_dirtied(page, mapping);
+ account_page_dirtied(page, mapping, memcg);
radix_tree_tag_set(&mapping->page_tree, page_index(page),
PAGECACHE_TAG_DIRTY);
spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
+
if (mapping->host) {
/* !PageAnon && !swapper_space */
__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
}
return 1;
}
+ mem_cgroup_end_page_stat(memcg);
return 0;
}
EXPORT_SYMBOL(__set_page_dirty_nobuffers);
@@ -2273,8 +2290,20 @@ EXPORT_SYMBOL(set_page_dirty_lock);
*/
void cancel_dirty_page(struct page *page)
{
- if (TestClearPageDirty(page))
- account_page_cleaned(page, page_mapping(page));
+ struct address_space *mapping = page_mapping(page);
+
+ if (mapping_cap_account_dirty(mapping)) {
+ struct mem_cgroup *memcg;
+
+ memcg = mem_cgroup_begin_page_stat(page);
+
+ if (TestClearPageDirty(page))
+ account_page_cleaned(page, mapping, memcg);
+
+ mem_cgroup_end_page_stat(memcg);
+ } else {
+ ClearPageDirty(page);
+ }
}
EXPORT_SYMBOL(cancel_dirty_page);
@@ -2295,6 +2324,8 @@ EXPORT_SYMBOL(cancel_dirty_page);
int clear_page_dirty_for_io(struct page *page)
{
struct address_space *mapping = page_mapping(page);
+ struct mem_cgroup *memcg;
+ int ret = 0;
BUG_ON(!PageLocked(page));
@@ -2334,13 +2365,16 @@ int clear_page_dirty_for_io(struct page *page)
* always locked coming in here, so we get the desired
* exclusion.
*/
+ memcg = mem_cgroup_begin_page_stat(page);
if (TestClearPageDirty(page)) {
+ mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_DIRTY);
dec_zone_page_state(page, NR_FILE_DIRTY);
dec_bdi_stat(inode_to_bdi(mapping->host),
BDI_RECLAIMABLE);
- return 1;
+ ret = 1;
}
- return 0;
+ mem_cgroup_end_page_stat(memcg);
+ return ret;
}
return TestClearPageDirty(page);
}
diff --git a/mm/rmap.c b/mm/rmap.c
index 24dd3f9fee27..8fc556ce2dcb 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -30,6 +30,8 @@
* swap_lock (in swap_duplicate, swap_info_get)
* mmlist_lock (in mmput, drain_mmlist and others)
* mapping->private_lock (in __set_page_dirty_buffers)
+ * mem_cgroup_{begin,end}_page_stat (memcg->move_lock)
+ * mapping->tree_lock (widely used)
* 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)
diff --git a/mm/truncate.c b/mm/truncate.c
index 0c360259c085..76e35ad97102 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -510,19 +510,24 @@ EXPORT_SYMBOL(invalidate_mapping_pages);
static int
invalidate_complete_page2(struct address_space *mapping, struct page *page)
{
+ struct mem_cgroup *memcg;
+ unsigned long flags;
+
if (page->mapping != mapping)
return 0;
if (page_has_private(page) && !try_to_release_page(page, GFP_KERNEL))
return 0;
- spin_lock_irq(&mapping->tree_lock);
+ memcg = mem_cgroup_begin_page_stat(page);
+ spin_lock_irqsave(&mapping->tree_lock, flags);
if (PageDirty(page))
goto failed;
BUG_ON(page_has_private(page));
- __delete_from_page_cache(page, NULL);
- spin_unlock_irq(&mapping->tree_lock);
+ __delete_from_page_cache(page, NULL, memcg);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
if (mapping->a_ops->freepage)
mapping->a_ops->freepage(page);
@@ -530,7 +535,8 @@ invalidate_complete_page2(struct address_space *mapping, struct page *page)
page_cache_release(page); /* pagecache ref */
return 1;
failed:
- spin_unlock_irq(&mapping->tree_lock);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
return 0;
}
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5e8eadd71bac..7582f9fcda92 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -579,10 +579,14 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
static int __remove_mapping(struct address_space *mapping, struct page *page,
bool reclaimed)
{
+ unsigned long flags;
+ struct mem_cgroup *memcg;
+
BUG_ON(!PageLocked(page));
BUG_ON(mapping != page_mapping(page));
- spin_lock_irq(&mapping->tree_lock);
+ memcg = mem_cgroup_begin_page_stat(page);
+ spin_lock_irqsave(&mapping->tree_lock, flags);
/*
* The non racy check for a busy page.
*
@@ -620,7 +624,8 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
swp_entry_t swap = { .val = page_private(page) };
mem_cgroup_swapout(page, swap);
__delete_from_swap_cache(page);
- spin_unlock_irq(&mapping->tree_lock);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
swapcache_free(swap);
} else {
void (*freepage)(struct page *);
@@ -640,8 +645,9 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
if (reclaimed && page_is_file_cache(page) &&
!mapping_exiting(mapping))
shadow = workingset_eviction(mapping, page);
- __delete_from_page_cache(page, shadow);
- spin_unlock_irq(&mapping->tree_lock);
+ __delete_from_page_cache(page, shadow, memcg);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
if (freepage != NULL)
freepage(page);
@@ -650,7 +656,8 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
return 1;
cannot_free:
- spin_unlock_irq(&mapping->tree_lock);
+ spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ mem_cgroup_end_page_stat(memcg);
return 0;
}