memcg: always enable kmemcg on the default hierarchy
On the default hierarchy, all memory consumption will be accounted
together and controlled by the same set of limits. Always enable
kmemcg on the default hierarchy.
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c94b686..8a5dd01 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4362,6 +4362,13 @@
if (ret)
return ret;
+ /* kmem is always accounted together on the default hierarchy */
+ if (cgroup_on_dfl(css->cgroup)) {
+ ret = memcg_activate_kmem(memcg, PAGE_COUNTER_MAX);
+ if (ret)
+ return ret;
+ }
+
/*
* Make sure the memcg is initialized: mem_cgroup_iter()
* orders reading memcg->initialized against its callers
