memcg: use css_get() in sock_update_memcg()
Use css_get/css_put instead of mem_cgroup_get/put.
Note, if at the same time someone is moving @current to a different
cgroup and removing the old cgroup, css_tryget() may return false, and
sock->sk_cgrp won't be initialized, which is fine.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Glauber Costa <glommer@openvz.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index bdeb82c..4c31a21a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -551,15 +551,15 @@
*/
if (sk->sk_cgrp) {
BUG_ON(mem_cgroup_is_root(sk->sk_cgrp->memcg));
- mem_cgroup_get(sk->sk_cgrp->memcg);
+ css_get(&sk->sk_cgrp->memcg->css);
return;
}
rcu_read_lock();
memcg = mem_cgroup_from_task(current);
cg_proto = sk->sk_prot->proto_cgroup(memcg);
- if (!mem_cgroup_is_root(memcg) && memcg_proto_active(cg_proto)) {
- mem_cgroup_get(memcg);
+ if (!mem_cgroup_is_root(memcg) &&
+ memcg_proto_active(cg_proto) && css_tryget(&memcg->css)) {
sk->sk_cgrp = cg_proto;
}
rcu_read_unlock();
@@ -573,7 +573,7 @@
struct mem_cgroup *memcg;
WARN_ON(!sk->sk_cgrp->memcg);
memcg = sk->sk_cgrp->memcg;
- mem_cgroup_put(memcg);
+ css_put(&sk->sk_cgrp->memcg->css);
}
}