From 6cd9dc3e75078ef646076fa63adfb9b85ced0b66 Mon Sep 17 00:00:00 2001 From: Chen Feng Date: Fri, 20 May 2016 16:59:02 -0700 Subject: [PATCH] mm/compaction.c: fix zoneindex in kcompactd() While testing the kcompactd in my platform 3G MEM only DMA ZONE. I found the kcompactd never wakeup. It seems the zoneindex has already minus 1 before. So the traverse here should be <=. It fixes a regression where kswapd could previously compact, but kcompactd not. Not a crash fix though. [akpm@linux-foundation.org: fix kcompactd_do_work() as well, per Hugh] Link: http://lkml.kernel.org/r/1463659121-84124-1-git-send-email-puck.chen@hisilicon.com Fixes: accf62422b3a ("mm, kswapd: replace kswapd compaction with waking up kcompactd") Signed-off-by: Chen Feng Acked-by: Vlastimil Babka Cc: Hugh Dickins Cc: Michal Hocko Cc: Kirill A. Shutemov Cc: Johannes Weiner Cc: Tejun Heo Cc: Zhuangluan Su Cc: Yiping Xu Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/compaction.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c index d8a20fcf8678..1427366ad673 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1862,7 +1862,7 @@ static bool kcompactd_node_suitable(pg_data_t *pgdat) struct zone *zone; enum zone_type classzone_idx = pgdat->kcompactd_classzone_idx; - for (zoneid = 0; zoneid < classzone_idx; zoneid++) { + for (zoneid = 0; zoneid <= classzone_idx; zoneid++) { zone = &pgdat->node_zones[zoneid]; if (!populated_zone(zone)) @@ -1897,7 +1897,7 @@ static void kcompactd_do_work(pg_data_t *pgdat) cc.classzone_idx); count_vm_event(KCOMPACTD_WAKE); - for (zoneid = 0; zoneid < cc.classzone_idx; zoneid++) { + for (zoneid = 0; zoneid <= cc.classzone_idx; zoneid++) { int status; zone = &pgdat->node_zones[zoneid]; -- 2.20.1