From cfc511557945812280699a92f171ddd2d254aca6 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Wed, 11 Feb 2015 15:25:12 -0800 Subject: [PATCH] mm, vmscan: wake up all pfmemalloc-throttled processes at once Kswapd in balance_pgdate() currently uses wake_up() on processes waiting in throttle_direct_reclaim(), which only wakes up a single process. This might leave processes waiting for longer than necessary, until the check is reached in the next loop iteration. Processes might also be left waiting if zone was fully balanced in single iteration. Note that the comment in balance_pgdat() also says "Wake them", so waking up a single process does not seem intentional. Thus, replace wake_up() with wake_up_all(). Signed-off-by: Vlastimil Babka Cc: Mel Gorman Cc: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Acked-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index dcd90c891d8e..f756a202d5d5 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3175,7 +3175,7 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order, */ if (waitqueue_active(&pgdat->pfmemalloc_wait) && pfmemalloc_watermark_ok(pgdat)) - wake_up(&pgdat->pfmemalloc_wait); + wake_up_all(&pgdat->pfmemalloc_wait); /* * Fragmentation may mean that the system cannot be rebalanced -- 2.30.2