diff mbox series

[5/8] mm: page_alloc: move free pages when converting block during isolation

Message ID 20230821183733.106619-6-hannes@cmpxchg.org (mailing list archive)
State New
Headers show
Series mm: page_alloc: freelist migratetype hygiene | expand

Commit Message

Johannes Weiner Aug. 21, 2023, 6:33 p.m. UTC 
When claiming a block during compaction isolation, move any remaining
free pages to the correct freelists as well, instead of stranding them
on the wrong list. Otherwise, this encourages incompatible page mixing
down the line, and thus long-term fragmentation.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
---
 mm/page_alloc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6c9f565b2613..6a4004f07123 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2586,9 +2586,12 @@  int __isolate_free_page(struct page *page, unsigned int order)
 			 * Only change normal pageblocks (i.e., they can merge
 			 * with others)
 			 */
-			if (migratetype_is_mergeable(mt))
+			if (migratetype_is_mergeable(mt)) {
 				set_pageblock_migratetype(page,
 							  MIGRATE_MOVABLE);
+				move_freepages_block(zone, page,
+						     MIGRATE_MOVABLE, NULL);
+			}
 		}
 	}