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@xxxxxxxxxxx> --- mm/page_alloc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) 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); + } } } -- 2.41.0