From 5eaf35ab1275c4048d5c64b7bd9e982af9ea6b9f Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 15 Oct 2020 20:05:46 -0700 Subject: mm/rmap: fix assumptions of THP size Ask the page what size it is instead of assuming it's PMD size. Do this for anon pages as well as file pages for when someone decides to support that. Leave the assumption alone for pages which are PMD mapped; we don't currently grow THPs beyond PMD size, so we don't need to change this code yet. Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton Reviewed-by: SeongJae Park Acked-by: Kirill A. Shutemov Cc: Huang Ying Link: https://lkml.kernel.org/r/20200908195539.25896-9-willy@infradead.org Signed-off-by: Linus Torvalds --- mm/rmap.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'mm/rmap.c') diff --git a/mm/rmap.c b/mm/rmap.c index 9425260774a1..1b84945d655c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1205,7 +1205,7 @@ void page_add_file_rmap(struct page *page, bool compound) VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page); lock_page_memcg(page); if (compound && PageTransHuge(page)) { - for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { + for (i = 0, nr = 0; i < thp_nr_pages(page); i++) { if (atomic_inc_and_test(&page[i]._mapcount)) nr++; } @@ -1246,7 +1246,7 @@ static void page_remove_file_rmap(struct page *page, bool compound) /* page still mapped by someone else? */ if (compound && PageTransHuge(page)) { - for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { + for (i = 0, nr = 0; i < thp_nr_pages(page); i++) { if (atomic_add_negative(-1, &page[i]._mapcount)) nr++; } @@ -1293,7 +1293,7 @@ static void page_remove_anon_compound_rmap(struct page *page) * Subpages can be mapped with PTEs too. Check how many of * them are still mapped. */ - for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { + for (i = 0, nr = 0; i < thp_nr_pages(page); i++) { if (atomic_add_negative(-1, &page[i]._mapcount)) nr++; } @@ -1303,10 +1303,10 @@ static void page_remove_anon_compound_rmap(struct page *page) * page of the compound page is unmapped, but at least one * small page is still mapped. */ - if (nr && nr < HPAGE_PMD_NR) + if (nr && nr < thp_nr_pages(page)) deferred_split_huge_page(page); } else { - nr = HPAGE_PMD_NR; + nr = thp_nr_pages(page); } if (unlikely(PageMlocked(page))) -- cgit v1.2.3