memcg: let css_get_next() rely upon rcu_read_lock()
authorHugh Dickins <hughd@google.com>
Wed, 21 Mar 2012 23:34:21 +0000 (16:34 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 22 Mar 2012 00:55:01 +0000 (17:55 -0700)
commitca464d69b19120a826aa2534de2511a6f542edf5
tree092582419a30825b8483640856483ea8ee56cf81
parent42aee6c495e07dba7410b863a360db6bb9ec6d66
memcg: let css_get_next() rely upon rcu_read_lock()

Remove lock and unlock around css_get_next()'s call to idr_get_next().
memcg iterators (only users of css_get_next) already did rcu_read_lock(),
and its comment demands that; but add a WARN_ON_ONCE to make sure of it.

Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/cgroup.c