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 <dan.carpenter@oracle.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan@kernel.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/compaction.c b/mm/compaction.c
index a08bf21..74a8c82 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -35,7 +35,7 @@
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 @@
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) {