Commit 728be28f authored by Kefeng Wang's avatar Kefeng Wang Committed by Andrew Morton
Browse files

mm: migrate: remove THP mapcount check in numamigrate_isolate_page() 

The check of THP mapped by multiple processes was introduced by commit
04fa5d6a ("mm: migrate: check page_count of THP before migrating") and
refactor by commit 340ef390 ("mm: numa: cleanup flow of transhuge page
migration"), which is out of date, since migrate_misplaced_page() is now
using the standard migrate_pages() for small pages and THPs, the reference
count checking is in folio_migrate_mapping(), so let's remove the special
check for THP.

Link: https://lkml.kernel.org/r/20230913095131.2426871-3-wangkefeng.wang@huawei.com


Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Suggested-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatar"Huang, Ying" <ying.huang@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent a8ac4a76

mm/migrate.c

+0 −4
Original line number Diff line number Diff line
@@ -2486,10 +2486,6 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) 
	int nr_pages = thp_nr_pages(page);

	int order = compound_order(page);



	/* Do not migrate THP mapped by multiple processes */

	if (PageTransHuge(page) && total_mapcount(page) > 1)

		return 0;



	/* Avoid migrating to a node that is nearly full */

	if (!migrate_balanced_pgdat(pgdat, nr_pages)) {

		int z;