From de3fab39348dff18c69a0cd04efee9c276a02f51 Mon Sep 17 00:00:00 2001 From: KOSAKI Motohiro Date: Fri, 15 Jan 2010 17:01:25 -0800 Subject: vmscan: kswapd: don't retry balance_pgdat() if all zones are unreclaimable Commit f50de2d3 (vmscan: have kswapd sleep for a short interval and double check it should be asleep) can cause kswapd to enter an infinite loop if running on a single-CPU system. If all zones are unreclaimble, sleeping_prematurely return 1 and kswapd will call balance_pgdat() again. but it's totally meaningless, balance_pgdat() doesn't anything against unreclaimable zone! Signed-off-by: KOSAKI Motohiro Cc: Mel Gorman Reported-by: Will Newton Reviewed-by: Minchan Kim Reviewed-by: Rik van Riel Tested-by: Will Newton Reviewed-by: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'mm/vmscan.c') diff --git a/mm/vmscan.c b/mm/vmscan.c index 885207a6b6b7..c26986c85ce0 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1922,6 +1922,9 @@ static int sleeping_prematurely(pg_data_t *pgdat, int order, long remaining) if (!populated_zone(zone)) continue; + if (zone_is_all_unreclaimable(zone)) + continue; + if (!zone_watermark_ok(zone, order, high_wmark_pages(zone), 0, 0)) return 1; -- cgit v1.2.3-59-g8ed1b