There is no need to execute the next loop if it not return in the first loop. So add a break at the end of the loop. There are only three rows in fallbacks, so reduce the first index size from MIGRATE_TYPES to MIGRATE_PCPTYPES. Signed-off-by: Yajun Deng <yajun.deng@xxxxxxxxx> --- mm/page_alloc.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1113483fa6c5..536e8d838fb5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2603,7 +2603,7 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, * * The other migratetypes do not have fallbacks. */ -static int fallbacks[MIGRATE_TYPES][MIGRATE_PCPTYPES - 1] = { +static int fallbacks[MIGRATE_PCPTYPES][MIGRATE_PCPTYPES - 1] = { [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE }, [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE }, [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE }, @@ -2861,7 +2861,7 @@ int find_suitable_fallback(struct free_area *area, unsigned int order, int i; int fallback_mt; - if (area->nr_free == 0) + if (area->nr_free == 0 || !migratetype_is_mergeable(migratetype)) return -1; *can_steal = false; @@ -2873,11 +2873,10 @@ int find_suitable_fallback(struct free_area *area, unsigned int order, if (can_steal_fallback(order, migratetype)) *can_steal = true; - if (!only_stealable) - return fallback_mt; - - if (*can_steal) + if (!only_stealable || *can_steal) return fallback_mt; + else + break; } return -1; -- 2.25.1