[PATCH] mm: vmscan: avoid a unnecessary reschedule in shrink_slab()

From: Xianting Tian
Date: Thu Oct 15 2020 - 23:52:06 EST


In shrink_slab(), it directly goes to 'out' label only when it
can't get the lock of shrinker_rwsew. In this case, it doesn't
do the real work of shrinking slab, so we don't need trigger a
reschedule by cond_resched().

Signed-off-by: Xianting Tian <tian.xianting@xxxxxxx>
---
mm/vmscan.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 466fc3144..676e97b28 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -687,8 +687,9 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid,
}

up_read(&shrinker_rwsem);
-out:
+
cond_resched();
+out:
return freed;
}

--
2.17.1