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memcg: add per cgroup dirty page accounting

When modifying PG_Dirty on cached file pages, update the new
MEM_CGROUP_STAT_DIRTY counter.  This is done in the same places where
global NR_FILE_DIRTY is managed.  The new memcg stat is visible in the
per memcg memory.stat cgroupfs file.  The most recent past attempt at
this was http://thread.gmane.org/gmane.linux.kernel.cgroups/8632

The new accounting supports future efforts to add per cgroup dirty
page throttling and writeback.  It also helps an administrator break
down a container's memory usage and provides evidence to understand
memcg oom kills (the new dirty count is included in memcg oom kill
messages).

The ability to move page accounting between memcg
(memory.move_charge_at_immigrate) makes this accounting more
complicated than the global counter.  The existing
mem_cgroup_{begin,end}_page_stat() lock is used to serialize move
accounting with stat updates.
Typical update operation:
	memcg = mem_cgroup_begin_page_stat(page)
	if (TestSetPageDirty()) {
		[...]
		mem_cgroup_update_page_stat(memcg)
	}
	mem_cgroup_end_page_stat(memcg)

Summary of mem_cgroup_end_page_stat() overhead:
- Without CONFIG_MEMCG it's a no-op
- With CONFIG_MEMCG and no inter memcg task movement, it's just
  rcu_read_lock()
- With CONFIG_MEMCG and inter memcg  task movement, it's
  rcu_read_lock() + spin_lock_irqsave()

A memcg parameter is added to several routines because their callers
now grab mem_cgroup_begin_page_stat() which returns the memcg later
needed by for mem_cgroup_update_page_stat().

Because mem_cgroup_begin_page_stat() may disable interrupts, some
adjustments are needed:
- move __mark_inode_dirty() from __set_page_dirty() to its caller.
  __mark_inode_dirty() locking does not want interrupts disabled.
- use spin_lock_irqsave(tree_lock) rather than spin_lock_irq() in
  __delete_from_page_cache(), replace_page_cache_page(),
  invalidate_complete_page2(), and __remove_mapping().

   text    data     bss      dec    hex filename
8925147 1774832 1785856 12485835 be84cb vmlinux-!CONFIG_MEMCG-before
8925339 1774832 1785856 12486027 be858b vmlinux-!CONFIG_MEMCG-after
                            +192 text bytes
8965977 1784992 1785856 12536825 bf4bf9 vmlinux-CONFIG_MEMCG-before
8966750 1784992 1785856 12537598 bf4efe vmlinux-CONFIG_MEMCG-after
                            +773 text bytes

Performance tests run on v4.0-rc1-36-g4f671fe2f952.  Lower is better for
all metrics, they're all wall clock or cycle counts.  The read and write
fault benchmarks just measure fault time, they do not include I/O time.

* CONFIG_MEMCG not set:
                            baseline                              patched
  kbuild                 1m25.030000(+-0.088% 3 samples)       1m25.426667(+-0.120% 3 samples)
  dd write 100 MiB          0.859211561 +-15.10%                  0.874162885 +-15.03%
  dd write 200 MiB          1.670653105 +-17.87%                  1.669384764 +-11.99%
  dd write 1000 MiB         8.434691190 +-14.15%                  8.474733215 +-14.77%
  read fault cycles       254.0(+-0.000% 10 samples)            253.0(+-0.000% 10 samples)
  write fault cycles     2021.2(+-3.070% 10 samples)           1984.5(+-1.036% 10 samples)

* CONFIG_MEMCG=y root_memcg:
                            baseline                              patched
  kbuild                 1m25.716667(+-0.105% 3 samples)       1m25.686667(+-0.153% 3 samples)
  dd write 100 MiB          0.855650830 +-14.90%                  0.887557919 +-14.90%
  dd write 200 MiB          1.688322953 +-12.72%                  1.667682724 +-13.33%
  dd write 1000 MiB         8.418601605 +-14.30%                  8.673532299 +-15.00%
  read fault cycles       266.0(+-0.000% 10 samples)            266.0(+-0.000% 10 samples)
  write fault cycles     2051.7(+-1.349% 10 samples)           2049.6(+-1.686% 10 samples)

* CONFIG_MEMCG=y non-root_memcg:
                            baseline                              patched
  kbuild                 1m26.120000(+-0.273% 3 samples)       1m25.763333(+-0.127% 3 samples)
  dd write 100 MiB          0.861723964 +-15.25%                  0.818129350 +-14.82%
  dd write 200 MiB          1.669887569 +-13.30%                  1.698645885 +-13.27%
  dd write 1000 MiB         8.383191730 +-14.65%                  8.351742280 +-14.52%
  read fault cycles       265.7(+-0.172% 10 samples)            267.0(+-0.000% 10 samples)
  write fault cycles     2070.6(+-1.512% 10 samples)           2084.4(+-2.148% 10 samples)

As expected anon page faults are not affected by this patch.

tj: Updated to apply on top of the recent cancel_dirty_page() changes.

Signed-off-by: Sha Zhengju <handai.szj@gmail.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
hifive-unleashed-5.1
Greg Thelen 2015-05-22 17:13:16 -04:00 committed by Jens Axboe
parent 11f81becca
commit c4843a7593
12 changed files with 156 additions and 39 deletions

View File

@ -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

View File

@ -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);

View File

@ -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;
}

View File

@ -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,

View File

@ -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);

View File

@ -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);
/*

View File

@ -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)

View File

@ -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);

View File

@ -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);
}

View File

@ -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)

View File

@ -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;
}

View File

@ -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;
}