memcg: avoid dangling reference count in creation failure.

When use_hierarchy is enabled, we acquire an extra reference count in
our parent during cgroup creation.  We don't release it, though, if any
failure exist in the creation process.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reported-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hiroyuki Kamezawa <kamezawa.hiroyuki@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Glauber Costa 2013-02-22 16:34:57 -08:00 committed by Linus Torvalds
parent 692e89abd1
commit e4715f01be

View file

@ -6196,6 +6196,8 @@ mem_cgroup_css_online(struct cgroup *cont)
* call __mem_cgroup_free, so return directly
*/
mem_cgroup_put(memcg);
if (parent->use_hierarchy)
mem_cgroup_put(parent);
}
return error;
}