[PATCH 2/2] mm: vmpressure: use mem_cgroup_is_root API

[Yang Shi]

Use mem_cgroup_is_root() API to check if memcg is root memcg instead of
open coding.

Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
---
 mm/vmpressure.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index 0590f00..d69019f 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -280,7 +280,7 @@ void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, bool tree,
 		enum vmpressure_levels level;
 
 		/* For now, no users for root-level efficiency */
-		if (!memcg || memcg == root_mem_cgroup)
+		if (!memcg || mem_cgroup_is_root(memcg))
 			return;
 
 		spin_lock(&vmpr->sr_lock);
-- 
1.8.3.1