[PATCH -V9 02/20] mm/THP: Use the right function when updating access flags
From: Aneesh Kumar K.V <hidden>
Date: 2013-05-22 16:58:26
Subsystem:
memory management, memory management - thp (transparent huge page), the rest · Maintainers:
Andrew Morton, David Hildenbrand, Lorenzo Stoakes, Linus Torvalds
From: "Aneesh Kumar K.V" <redacted> We should use pmdp_set_access_flags to update access flags. Archs like powerpc use extra checks(_PAGE_BUSY) when updating a hugepage PTE. A set_pmd_at doesn't do those checks. We should use set_pmd_at only when updating a none hugepage PTE. Signed-off-by: Aneesh Kumar K.V <redacted> --- mm/huge_memory.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 362c329..dab90fd 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c@@ -1265,7 +1265,9 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma, * young bit, instead of the current set_pmd_at. */ _pmd = pmd_mkyoung(pmd_mkdirty(*pmd)); - set_pmd_at(mm, addr & HPAGE_PMD_MASK, pmd, _pmd); + if (pmdp_set_access_flags(vma, addr & HPAGE_PMD_MASK, + pmd, _pmd, 1)) + update_mmu_cache_pmd(vma, addr, pmd); } if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) { if (page->mapping && trylock_page(page)) {
--
1.8.1.2