From: Baolin Wang <baolin.wang@linux.alibaba.com> mainline inclusion from mainline-v6.12-rc1 commit fda6d4de064a9d37414df36d45836898fff5e165 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IAXCD2 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Patch series "support shmem mTHP collapse", v2. Shmem already supports mTHP allocation[1], and this patchset adds support for shmem mTHP collapse, as well as adding relevant test cases. This patch (of 5): Expand the is_refcount_suitable() to support reference checks for file folios, as preparation for supporting shmem mTHP collapse. Link: https://lkml.kernel.org/r/cover.1724140601.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/eae4cb3195ebbb654bfb7967cb7261d4e4e7c7fa.172414060... Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Barry Song <21cnbao@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> --- mm/khugepaged.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/mm/khugepaged.c b/mm/khugepaged.c index d585ee8357da..007684e8b888 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -555,12 +555,14 @@ static void release_pte_pages(pte_t *pte, pte_t *_pte, static bool is_refcount_suitable(struct folio *folio) { - int expected_refcount; + int expected_refcount = folio_mapcount(folio); - expected_refcount = folio_mapcount(folio); - if (folio_test_swapcache(folio)) + if (!folio_test_anon(folio) || folio_test_swapcache(folio)) expected_refcount += folio_nr_pages(folio); + if (folio_test_private(folio)) + expected_refcount++; + return folio_ref_count(folio) == expected_refcount; } @@ -2300,8 +2302,7 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr, break; } - if (folio_ref_count(folio) != - 1 + folio_mapcount(folio) + folio_test_private(folio)) { + if (!is_refcount_suitable(folio)) { result = SCAN_PAGE_COUNT; break; } -- 2.33.0