Commit 149c33e1 authored by Mel Gorman's avatar Mel Gorman
Browse files

mm: migrate: Drop the misplaced pages reference count if the target node is full 



If we have to avoid migrating to a node that is nearly full, put page
and return zero.

Signed-off-by: default avatarHillf Danton <dhillf@gmail.com>
Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
parent 7039e1db

mm/migrate.c

+10 −7
Original line number Diff line number Diff line
@@ -1489,18 +1489,21 @@ int migrate_misplaced_page(struct page *page, int node) 
		}

		isolated = 1;



		/*

		 * Page is isolated which takes a reference count so now the

		 * callers reference can be safely dropped without the page

		 * disappearing underneath us during migration

		 */

		put_page(page);



		page_lru = page_is_file_cache(page);

		inc_zone_page_state(page, NR_ISOLATED_ANON + page_lru);

		list_add(&page->lru, &migratepages);

	}



	/*

	 * Page is either isolated or there is not enough space on the target

	 * node. If isolated, then it has taken a reference count and the

	 * callers reference can be safely dropped without the page

	 * disappearing underneath us during migration. Otherwise the page is

	 * not to be migrated but the callers reference should still be

	 * dropped so it does not leak.

	 */

	put_page(page);



	if (isolated) {

		int nr_remaining;