[PATCH] mm: vmscan: fix memcg-aware shrinkers not called on global reclaim

From: Vladimir Davydov
Date: Mon Aug 01 2016 - 09:19:38 EST


We must call shrink_slab() for each memory cgroup on both global and
memcg reclaim in shrink_node_memcg(). Commit d71df22b55099 accidentally
changed that so that now shrink_slab() is only called with memcg != NULL
on memcg reclaim. As a result, memcg-aware shrinkers (including
dentry/inode) are never invoked on global reclaim. Fix that.

Fixes: d71df22b55099 ("mm, vmscan: begin reclaiming pages on a per-node basis")
Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>
---
mm/vmscan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 650d26832569..374d95d04178 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2561,7 +2561,7 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
shrink_node_memcg(pgdat, memcg, sc, &lru_pages);
node_lru_pages += lru_pages;

- if (!global_reclaim(sc))
+ if (memcg)
shrink_slab(sc->gfp_mask, pgdat->node_id,
memcg, sc->nr_scanned - scanned,
lru_pages);
--
2.1.4