From 6c5c7b9f3352728af490183f71d350bb658ffb75 Mon Sep 17 00:00:00 2001 From: Zi Yan Date: Fri, 25 Sep 2020 21:19:14 -0700 Subject: [PATCH] mm/migrate: correct thp migration stats PageTransHuge returns true for both thp and hugetlb, so thp stats was counting both thp and hugetlb migrations. Exclude hugetlb migration by setting is_thp variable right. Clean up thp handling code too when we are there. Fixes: 1a5bae25e3cf ("mm/vmstat: add events for THP migration without split") Signed-off-by: Zi Yan Signed-off-by: Andrew Morton Reviewed-by: Daniel Jordan Cc: Anshuman Khandual Link: https://lkml.kernel.org/r/20200917210413.1462975-1-zi.yan@sent.com Signed-off-by: Linus Torvalds --- mm/migrate.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index aecb1433cf3c..04a98bb2f568 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1446,7 +1446,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, * Capture required information that might get lost * during migration. */ - is_thp = PageTransHuge(page); + is_thp = PageTransHuge(page) && !PageHuge(page); nr_subpages = thp_nr_pages(page); cond_resched(); @@ -1472,7 +1472,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, * we encounter them after the rest of the list * is processed. */ - if (PageTransHuge(page) && !PageHuge(page)) { + if (is_thp) { lock_page(page); rc = split_huge_page_to_list(page, from); unlock_page(page); @@ -1481,8 +1481,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, nr_thp_split++; goto retry; } - } - if (is_thp) { + nr_thp_failed++; nr_failed += nr_subpages; goto out;