[PATCH 3/8] memcg: convert to use cgroup_is_ancestor()

[Li Zefan <lizefan@huawei.com>]

This is a preparation to kill css_id.

Signed-off-by: Li Zefan <lizefan@huawei.com>
---
 mm/memcontrol.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 5aa6e91..14f1375 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1383,7 +1383,7 @@ bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
 		return true;
 	if (!root_memcg->use_hierarchy || !memcg)
 		return false;
-	return css_is_ancestor(&memcg->css, &root_memcg->css);
+	return cgroup_is_ancestor(memcg->css.cgroup, root_memcg->css.cgroup);
 }
 
 static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
-- 
1.8.0.2