From: Hugh Dickins <hughd@google.com> stable inclusion from linux-4.19.197 commit a027b699161023c017b816b61be9990e3f9286f4 -------------------------------- [ Upstream commit 6d0fd5987657cb0c9756ce684e3a74c0f6351728 ] page_vma_mapped_walk() cleanup: get the hugetlbfs PageHuge case out of the way at the start, so no need to worry about it later. Link: https://lkml.kernel.org/r/e31a483c-6d73-a6bb-26c5-43c3b880a2@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Peter Xu <peterx@redhat.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Wang Yugui <wangyugui@e16-tech.com> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <shy828301@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- mm/page_vma_mapped.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index d146f6d31a624..036ce20bb154c 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -148,10 +148,11 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) if (pvmw->pmd && !pvmw->pte) return not_found(pvmw); - if (pvmw->pte) - goto next_pte; - if (unlikely(PageHuge(page))) { + /* The only possible mapping was handled on last iteration */ + if (pvmw->pte) + return not_found(pvmw); + /* when pud is not present, pte will be NULL */ pvmw->pte = huge_pte_offset(mm, pvmw->address, PAGE_SIZE << compound_order(page)); @@ -164,6 +165,9 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return not_found(pvmw); return true; } + + if (pvmw->pte) + goto next_pte; restart: pgd = pgd_offset(mm, pvmw->address); if (!pgd_present(*pgd)) @@ -229,7 +233,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return true; next_pte: /* Seek to next pte only makes sense for THP */ - if (!PageTransHuge(page) || PageHuge(page)) + if (!PageTransHuge(page)) return not_found(pvmw); end = vma_address_end(page, pvmw->vma); do { -- 2.25.1