From: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> Subject: mm: vmpressure: use mem_cgroup_is_root API Use mem_cgroup_is_root() API to check if memcg is root memcg instead of open coding. Link: http://lkml.kernel.org/r/1581398649-125989-2-git-send-email-yang.shi@xxxxxxxxxxxxxxxxx Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: David Rientjes <rientjes@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmpressure.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/vmpressure.c~mm-vmpressure-use-mem_cgroup_is_root-api +++ a/mm/vmpressure.c @@ -280,7 +280,7 @@ void vmpressure(gfp_t gfp, struct mem_cg 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); _
