From: Shakeel Butt <shakeelb@xxxxxxxxxx> Subject: mm: vmscan: consistent update to pgrefill The vmstat pgrefill is useful together with pgscan and pgsteal stats to measure the reclaim efficiency. However vmstat's pgrefill is not updated consistently at system level. It gets updated for both global and memcg reclaim however pgscan and pgsteal are updated for only global reclaim. So, update pgrefill only for global reclaim. If someone is interested in the stats representing both system level as well as memcg level reclaim, then consult the root memcg's memory.stat instead of /proc/vmstat. Link: http://lkml.kernel.org/r/20200711011459.1159929-1-shakeelb@xxxxxxxxxx Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx> Acked-by: Yafang Shao <laoar.shao@xxxxxxxxx> Acked-by: Roman Gushchin <guro@xxxxxx> Acked-by: Chris Down <chris@xxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmscan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/vmscan.c~mm-vmscan-consistent-update-to-pgrefill +++ a/mm/vmscan.c @@ -2030,7 +2030,8 @@ static void shrink_active_list(unsigned __mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, nr_taken); - __count_vm_events(PGREFILL, nr_scanned); + if (!cgroup_reclaim(sc)) + __count_vm_events(PGREFILL, nr_scanned); __count_memcg_events(lruvec_memcg(lruvec), PGREFILL, nr_scanned); spin_unlock_irq(&pgdat->lru_lock); _