From 1dd214b8f21ca46d5431be9b2db8513c59e07a26 Mon Sep 17 00:00:00 2001 From: Zi Yan Date: Tue, 22 Mar 2022 14:43:05 -0700 Subject: mm: page_alloc: avoid merging non-fallbackable pageblocks with others This is done in addition to MIGRATE_ISOLATE pageblock merge avoidance. It prepares for the upcoming removal of the MAX_ORDER-1 alignment requirement for CMA and alloc_contig_range(). MIGRATE_HIGHATOMIC should not merge with other migratetypes like MIGRATE_ISOLATE and MIGRARTE_CMA[1], so this commit prevents that too. Remove MIGRATE_CMA and MIGRATE_ISOLATE from fallbacks list, since they are never used. [1] https://lore.kernel.org/linux-mm/20211130100853.GP3366@techsingularity.net/ Link: https://lkml.kernel.org/r/20220124175957.1261961-1-zi.yan@sent.com Signed-off-by: Zi Yan Acked-by: Mel Gorman Acked-by: David Hildenbrand Acked-by: Vlastimil Babka Acked-by: Mike Rapoport Reviewed-by: Oscar Salvador Cc: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/linux/mmzone.h') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index aed44e9b5d89..71b77aab748d 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -83,6 +83,17 @@ static inline bool is_migrate_movable(int mt) return is_migrate_cma(mt) || mt == MIGRATE_MOVABLE; } +/* + * Check whether a migratetype can be merged with another migratetype. + * + * It is only mergeable when it can fall back to other migratetypes for + * allocation. See fallbacks[MIGRATE_TYPES][3] in page_alloc.c. + */ +static inline bool migratetype_is_mergeable(int mt) +{ + return mt < MIGRATE_PCPTYPES; +} + #define for_each_migratetype_order(order, type) \ for (order = 0; order < MAX_ORDER; order++) \ for (type = 0; type < MIGRATE_TYPES; type++) -- cgit v1.2.3