On 2/12/20 12:23 AM, Michal Hocko wrote:
On Tue 11-02-20 13:24:09, Yang Shi wrote:
Use mem_cgroup_is_root() API to check if memcg is root memcg instead of
open coding.
Yes, the direct use outside of memcontrol.c should be really an
exception. The only other similar case is cgwb_bdi_init and there is no
easy way to replace - except for adding a helper which is not worth it.
Yes, it seems so. cgwb_bdi_init just deferences root_mem_cgroup to
access its css. It is the only user outside memcontrol.c, so I agree a
helper for it might be overkilling. Once we have more users, it should
be considered.
Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Thanks.
Thanks!
---
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
