diff options
| author | Sha Zhengju <[email protected]> | 2013-09-12 15:13:52 -0700 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2013-09-12 15:38:02 -0700 |
| commit | 658b72c5a7a033f0dde61b15dff86bf423ce425e (patch) | |
| tree | 271352bf3a3c5ad13acca1ca425dfb8b53d1e190 | |
| parent | 68b4876d996e8749142b2895bc2e251448996363 (diff) | |
memcg: check for proper lock held in mem_cgroup_update_page_stat
We should call mem_cgroup_begin_update_page_stat() before
mem_cgroup_update_page_stat() to get proper locks, however the latter
doesn't do any checking that we use proper locking, which would be hard.
Suggested by Michal Hock we could at least test for rcu_read_lock_held()
because RCU is held if !mem_cgroup_disabled().
Signed-off-by: Sha Zhengju <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Reviewed-by: Greg Thelen <[email protected]>
Cc: Fengguang Wu <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
| -rw-r--r-- | mm/memcontrol.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index f3803462a7e6..0093bc36c5fc 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2225,6 +2225,7 @@ void mem_cgroup_update_page_stat(struct page *page, if (mem_cgroup_disabled()) return; + VM_BUG_ON(!rcu_read_lock_held()); memcg = pc->mem_cgroup; if (unlikely(!memcg || !PageCgroupUsed(pc))) return; |