[PATCH] mm: skip current when memcg reclaim

[Huangzhaoyang]

From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>

Sibling thread of the same process could refault the reclaimed pages
in the same time, which would be typical in None global reclaim and
introduce thrashing.
---
 mm/vmscan.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5199b96..ebbdc37 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2841,6 +2841,11 @@ static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc)
 				sc->memcg_low_skipped = 1;
 				continue;
 			}
+			/*
+			 * Don't bother current when its memcg is below low
+			 */
+			if (get_mem_cgroup_from_mm(current->mm) == memcg)
+				continue;
 			memcg_memory_event(memcg, MEMCG_LOW);
 		}
 
-- 
1.9.1