cgroup: remove unnecessary 0 check from css_from_id()

css_idr allocation starts at 1, so index 0 will never point to an item.
css_from_id() currently filters that before asking idr_find(), but
idr_find() would also just return NULL, so this is not needed.

Link: http://lkml.kernel.org/r/20160617162427.GC19084@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Johannes Weiner 2016-07-26 15:27:01 -07:00 committed by Linus Torvalds
parent 1fe4d021ac
commit cb773df88a
1 changed files with 1 additions and 1 deletions

View File

@ -6166,7 +6166,7 @@ struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss) struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss)
{ {
WARN_ON_ONCE(!rcu_read_lock_held()); WARN_ON_ONCE(!rcu_read_lock_held());
return id > 0 ? idr_find(&ss->css_idr, id) : NULL; return idr_find(&ss->css_idr, id);
} }
/** /**