[Devel] [PATCH v11 04/15] memcg: move initialization to memcg creation

[Vladimir Davydov]

From: Glauber Costa <glommer at openvz.org>

Those structures are only used for memcgs that are effectively using
kmemcg. However, in a later patch I intend to use scan that list
inconditionally (list empty meaning no kmem caches present), which
simplifies the code a lot.

So move the initialization to early kmem creation.

Signed-off-by: Glauber Costa <glommer at openvz.org>
Cc: Dave Chinner <dchinner at redhat.com>
Cc: Mel Gorman <mgorman at suse.de>
Cc: Rik van Riel <riel at redhat.com>
Cc: Johannes Weiner <hannes at cmpxchg.org>
Cc: Michal Hocko <mhocko at suse.cz>
Cc: Hugh Dickins <hughd at google.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
Cc: Andrew Morton <akpm at linux-foundation.org>
---
 mm/memcontrol.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 41c216a..5104d1f 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3120,8 +3120,6 @@ int memcg_update_cache_sizes(struct mem_cgroup *memcg)
 	}
 
 	memcg->kmemcg_id = num;
-	INIT_LIST_HEAD(&memcg->memcg_slab_caches);
-	mutex_init(&memcg->slab_caches_mutex);
 	return 0;
 }
 
@@ -5916,6 +5914,8 @@ static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
 {
 	int ret;
 
+	INIT_LIST_HEAD(&memcg->memcg_slab_caches);
+	mutex_init(&memcg->slab_caches_mutex);
 	memcg->kmemcg_id = -1;
 	ret = memcg_propagate_kmem(memcg);
 	if (ret)
-- 
1.7.10.4