Commit 556162bf authored by Miaohe Lin's avatar Miaohe Lin Committed by Andrew Morton
Browse files

mm: compaction: clean up comment about async compaction in isolate_migratepages 

Since commit 282722b0 ("mm, compaction: restrict async compaction to
pageblocks of same migratetype"), async direct compaction is restricted to
scan the pageblocks of same migratetype.  Correct the comment accordingly.

Link: https://lkml.kernel.org/r/20220418141253.24298-9-linmiaohe@huawei.com


Signed-off-by: default avatarMiaohe Lin <linmiaohe@huawei.com>
Cc: Charan Teja Kalla <charante@codeaurora.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Pintu Kumar <pintu@codeaurora.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 66fe1cf7

mm/compaction.c

+6 −6
Original line number Diff line number Diff line
@@ -1941,12 +1941,12 @@ static isolate_migrate_t isolate_migratepages(struct compact_control *cc) 
			continue;



		/*

		 * For async compaction, also only scan in MOVABLE blocks

		 * without huge pages. Async compaction is optimistic to see

		 * if the minimum amount of work satisfies the allocation.

		 * The cached PFN is updated as it's possible that all

		 * remaining blocks between source and target are unsuitable

		 * and the compaction scanners fail to meet.

		 * For async direct compaction, only scan the pageblocks of the

		 * same migratetype without huge pages. Async direct compaction

		 * is optimistic to see if the minimum amount of work satisfies

		 * the allocation. The cached PFN is updated as it's possible

		 * that all remaining blocks between source and target are

		 * unsuitable and the compaction scanners fail to meet.

		 */

		if (!suitable_migration_source(cc, page)) {

			update_cached_migrate(cc, block_end_pfn);