[PATCH 08/16] mm/page_alloc: add missing is_migrate_isolate() check in set_page_guard()

From: Miaohe Lin
Date: Fri Sep 09 2022 - 05:27:48 EST


In MIGRATE_ISOLATE case, zone freepage state shouldn't be modified as
caller will take care of it. Add missing is_migrate_isolate() here to
avoid possible unbalanced freepage state.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/page_alloc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a35ef385d906..94baf33da865 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -873,7 +873,8 @@ static inline bool set_page_guard(struct zone *zone, struct page *page,
INIT_LIST_HEAD(&page->buddy_list);
set_page_private(page, order);
/* Guard pages are not available for any usage */
- __mod_zone_freepage_state(zone, -(1 << order), migratetype);
+ if (!is_migrate_isolate(migratetype))
+ __mod_zone_freepage_state(zone, -(1 << order), migratetype);

return true;
}
--
2.23.0