The quilt patch titled
Subject: mm/page_vma_mapped.c: check possible huge PMD map with transhuge_vma_suitable()
has been removed from the -mm tree. Its filename was
mm-pvmw-check-possible-huge-pmd-map-by-transhuge_vma_suitable.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Yang Shi <shy828301@xxxxxxxxx>
Subject: mm/page_vma_mapped.c: check possible huge PMD map with transhuge_vma_suitable()
Date: Fri, 13 May 2022 12:17:05 -0700
IIUC page_vma_mapped_walk() checks if the vma is possibly huge PMD mapped
with transparent_hugepage_active() and "pvmw->nr_pages >= HPAGE_PMD_NR".
Actually pvmw->nr_pages is returned by compound_nr() or folio_nr_pages(),
so the page should be THP as long as "pvmw->nr_pages >= HPAGE_PMD_NR".
And it is guaranteed THP is allocated for valid VMA in the first place.
But it may be not PMD mapped if the VMA is file VMA and it is not properly
aligned. The transhuge_vma_suitable() is used to do such check, so
replace transparent_hugepage_active() to it, which is too heavy and
overkilling.
Link: https://lkml.kernel.org/r/20220513191705.457775-1-shy828301@xxxxxxxxx
Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/huge_mm.h | 8 ++++++--
mm/page_vma_mapped.c | 2 +-
2 files changed, 7 insertions(+), 3 deletions(-)
--- a/include/linux/huge_mm.h~mm-pvmw-check-possible-huge-pmd-map-by-transhuge_vma_suitable
+++ a/include/linux/huge_mm.h
@@ -117,8 +117,10 @@ extern struct kobj_attribute shmem_enabl
extern unsigned long transparent_hugepage_flags;
static inline bool transhuge_vma_suitable(struct vm_area_struct *vma,
- unsigned long haddr)
+ unsigned long addr)
{
+ unsigned long haddr;
+
/* Don't have to check pgoff for anonymous vma */
if (!vma_is_anonymous(vma)) {
if (!IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff,
@@ -126,6 +128,8 @@ static inline bool transhuge_vma_suitabl
return false;
}
+ haddr = addr & HPAGE_PMD_MASK;
+
if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
return false;
return true;
@@ -342,7 +346,7 @@ static inline bool transparent_hugepage_
}
static inline bool transhuge_vma_suitable(struct vm_area_struct *vma,
- unsigned long haddr)
+ unsigned long addr)
{
return false;
}
--- a/mm/page_vma_mapped.c~mm-pvmw-check-possible-huge-pmd-map-by-transhuge_vma_suitable
+++ a/mm/page_vma_mapped.c
@@ -243,7 +243,7 @@ restart:
* cleared *pmd but not decremented compound_mapcount().
*/
if ((pvmw->flags & PVMW_SYNC) &&
- transparent_hugepage_active(vma) &&
+ transhuge_vma_suitable(vma, pvmw->address) &&
(pvmw->nr_pages >= HPAGE_PMD_NR)) {
spinlock_t *ptl = pmd_lock(mm, pvmw->pmd);
_
Patches currently in -mm which might be from shy828301@xxxxxxxxx are
mm-khugepaged-check-thp-flag-in-hugepage_vma_check.patch
mm-thp-consolidate-vma-size-check-to-transhuge_vma_suitable.patch
mm-khugepaged-better-comments-for-anon-vma-check-in-hugepage_vma_revalidate.patch
mm-thp-kill-transparent_hugepage_active.patch
mm-thp-kill-__transhuge_page_enabled.patch
mm-khugepaged-reorg-some-khugepaged-helpers.patch
doc-proc-fix-the-description-to-thpeligible.patch
