From fbabe4b4032f2a53a3a2244c3e1a75af09c4d658 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Mon, 2 Aug 2021 11:00:35 +0800 Subject: [PATCH] mm: page_vma_mapped_walk(): prettify PVMW_MIGRATION block stable inclusion from linux-4.19.197 commit d4b99cf445d24089255a49ff927ed8884ca2f7f5 -------------------------------- [ Upstream commit e2e1d4076c77b3671cf8ce702535ae7dee3acf89 ] page_vma_mapped_walk() cleanup: rearrange the !pmd_present() block to follow the same "return not_found, return not_found, return true" pattern as the block above it (note: returning not_found there is never premature, since existence or prior existence of huge pmd guarantees good alignment). Link: https://lkml.kernel.org/r/378c8650-1488-2edf-9647-32a53cf2e21@google.com Signed-off-by: Hugh Dickins Acked-by: Kirill A. Shutemov Reviewed-by: Peter Xu Cc: Alistair Popple Cc: Matthew Wilcox Cc: Ralph Campbell Cc: Wang Yugui Cc: Will Deacon Cc: Yang Shi Cc: Zi Yan Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Yang Yingliang --- mm/page_vma_mapped.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index 7e1db77b096a..e32ed7912923 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -194,24 +194,22 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) if (pmd_page(pmde) != page) return not_found(pvmw); return true; - } else if (!pmd_present(pmde)) { - if (thp_migration_supported()) { - if (!(pvmw->flags & PVMW_MIGRATION)) - return not_found(pvmw); - if (is_migration_entry(pmd_to_swp_entry(pmde))) { - swp_entry_t entry = pmd_to_swp_entry(pmde); + } + if (!pmd_present(pmde)) { + swp_entry_t entry; - if (migration_entry_to_page(entry) != page) - return not_found(pvmw); - return true; - } - } - return not_found(pvmw); - } else { - /* THP pmd was split under us: handle on pte level */ - spin_unlock(pvmw->ptl); - pvmw->ptl = NULL; + if (!thp_migration_supported() || + !(pvmw->flags & PVMW_MIGRATION)) + return not_found(pvmw); + entry = pmd_to_swp_entry(pmde); + if (!is_migration_entry(entry) || + migration_entry_to_page(entry) != page) + return not_found(pvmw); + return true; } + /* THP pmd was split under us: handle on pte level */ + spin_unlock(pvmw->ptl); + pvmw->ptl = NULL; } else if (!pmd_present(pmde)) { /* * If PVMW_SYNC, take and drop THP pmd lock so that we -- GitLab