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| author | Johannes Weiner <hannes@cmpxchg.org> | 2016-03-15 14:57:25 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-15 16:55:16 -0700 |
| commit | fdf1cdb91b6ab7a8a91df68c384f36b8a0909cab (patch) | |
| tree | 828ad38946acad9990dcc733a10ebdeed0c1fbd5 /mm/page-writeback.c | |
| parent | 62cccb8c8e7a3ca233f49d5e7dcb1557d25465cd (diff) | |
| download | talos-obmc-linux-fdf1cdb91b6ab7a8a91df68c384f36b8a0909cab.tar.gz talos-obmc-linux-fdf1cdb91b6ab7a8a91df68c384f36b8a0909cab.zip | |
mm: remove unnecessary uses of lock_page_memcg()
There are several users that nest lock_page_memcg() inside lock_page()
to prevent page->mem_cgroup from changing. But the page lock prevents
pages from moving between cgroups, so that is unnecessary overhead.
Remove lock_page_memcg() in contexts with locked contexts and fix the
debug code in the page stat functions to be okay with the page lock.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/page-writeback.c')
| -rw-r--r-- | mm/page-writeback.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/mm/page-writeback.c b/mm/page-writeback.c index d7cf2c53d125..11ff8f758631 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2700,7 +2700,6 @@ int clear_page_dirty_for_io(struct page *page) * always locked coming in here, so we get the desired * exclusion. */ - lock_page_memcg(page); wb = unlocked_inode_to_wb_begin(inode, &locked); if (TestClearPageDirty(page)) { mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_DIRTY); @@ -2709,7 +2708,6 @@ int clear_page_dirty_for_io(struct page *page) ret = 1; } unlocked_inode_to_wb_end(inode, locked); - unlock_page_memcg(page); return ret; } return TestClearPageDirty(page); |
