From aad6ec3777bf4930d4f7293745cc4c17a2d87947 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 21 Mar 2012 16:33:54 -0700 Subject: [PATCH] mm: compaction: make compact_control order signed "order" is -1 when compacting via /proc/sys/vm/compact_memory. Making it unsigned causes a bug in __compact_pgdat() when we test: if (cc->order < 0 || !compaction_deferred(zone, cc->order)) compact_zone(zone, cc); [akpm@linux-foundation.org: make __compact_pgdat()'s comparison match other code sites] Signed-off-by: Dan Carpenter Cc: Mel Gorman Cc: Minchan Kim Reviewed-by: Rik van Riel Cc: Andrea Arcangeli 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 a08bf219f88c..74a8c825ff28 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -35,7 +35,7 @@ struct compact_control { unsigned long migrate_pfn; /* isolate_migratepages search base */ bool sync; /* Synchronous migration */ - unsigned int order; /* order a direct compactor needs */ + int order; /* order a direct compactor needs */ int migratetype; /* MOVABLE, RECLAIMABLE etc */ struct zone *zone; }; @@ -692,7 +692,7 @@ static int __compact_pgdat(pg_data_t *pgdat, struct compact_control *cc) INIT_LIST_HEAD(&cc->freepages); INIT_LIST_HEAD(&cc->migratepages); - if (cc->order < 0 || !compaction_deferred(zone, cc->order)) + if (cc->order == -1 || !compaction_deferred(zone, cc->order)) compact_zone(zone, cc); if (cc->order > 0) {