memcg: correct comments for __mem_cgroup_begin_update_page_stat

Signed-off-by: Qiang Huang <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Qiang Huang 2014-06-04 16:08:22 -07:00 • committed by Linus Torvalds
commit b5ffc8560c

View file

@ -2276,12 +2276,11 @@ cleanup:
}
/*
* Currently used to update mapped file statistics, but the routine can be
* generalized to update other statistics as well.
* Used to update mapped file or writeback or other statistics.
*
* Notes: Race condition
*
* We usually use page_cgroup_lock() for accessing page_cgroup member but
* We usually use lock_page_cgroup() for accessing page_cgroup member but
* it tends to be costly. But considering some conditions, we doesn't need
* to do so _always_.
*
@ -2295,8 +2294,8 @@ cleanup:
* by flags.
*
* Considering "move", this is an only case we see a race. To make the race
* small, we check mm->moving_account and detect there are possibility of race
* If there is, we take a lock.
* small, we check memcg->moving_account and detect there are possibility
* of race or not. If there is, we take a lock.
*/
void __mem_cgroup_begin_update_page_stat(struct page *page,