From a8ac4a767dcd9d87d8229045904d9fe15ea5e0e8 Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Wed, 13 Sep 2023 17:51:24 +0800 Subject: mm: migrate: remove PageTransHuge check in numamigrate_isolate_page() Patch series "mm: migrate: more folio conversion and unification", v3. Convert more migrate functions to use a folio, it is also a preparation for large folio migration support when balancing numa. This patch (of 8): The assert VM_BUG_ON_PAGE(order && !PageTransHuge(page), page) is not very useful, 1) for a tail/base page, order = 0, for a head page, the order > 0 && PageTransHuge() is true 2) there is a PageCompound() check and only base page is handled in do_numa_page(), and do_huge_pmd_numa_page() only handle PMD-mapped THP 3) even though the page is a tail page, isolate_lru_page() will post a warning, and fail to isolate the page 4) if large folio/pte-mapped THP migration supported in the future, we could migrate the entire folio if numa fault on a tail page so just remove the check. Link: https://lkml.kernel.org/r/20230913095131.2426871-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20230913095131.2426871-2-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Suggested-by: Matthew Wilcox (Oracle) Cc: David Hildenbrand Cc: Huang Ying Cc: Hugh Dickins Cc: Mike Kravetz Cc: Zi Yan Signed-off-by: Andrew Morton --- mm/migrate.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'mm/migrate.c') diff --git a/mm/migrate.c b/mm/migrate.c index eb6bc4053bc4..d1b8ab5a2417 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2486,8 +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); - VM_BUG_ON_PAGE(order && !PageTransHuge(page), page); - /* Do not migrate THP mapped by multiple processes */ if (PageTransHuge(page) && total_mapcount(page) > 1) return 0; -- cgit v1.2.3