The quilt patch titled
Subject: mm/vmwgfx: simplify pmd & pud mapping dirty helpers
has been removed from the -mm tree. Its filename was
mm-vmwgfx-simplify-pmd-pud-mapping-dirty-helpers.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: Hugh Dickins <hughd@xxxxxxxxxx>
Subject: mm/vmwgfx: simplify pmd & pud mapping dirty helpers
Date: Thu, 8 Jun 2023 18:20:04 -0700 (PDT)
wp_clean_pmd_entry() need not check pmd_trans_unstable() or pmd_none(),
wp_clean_pud_entry() need not check pud_trans_unstable() or pud_none():
it's just the ACTION_CONTINUE when trans_huge or devmap that's needed to
prevent splitting, and we're hoping to remove pmd_trans_unstable(). Is
that PUD #ifdef necessary? Maybe some configs are missing a stub.
Link: https://lkml.kernel.org/r/d3379c7-65db-26d3-1764-8e866490925f@xxxxxxxxxx
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Axel Rasmussen <axelrasmussen@xxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: "Huang, Ying" <ying.huang@xxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
Cc: SeongJae Park <sj@xxxxxxxxxx>
Cc: Song Liu <song@xxxxxxxxxx>
Cc: Steven Price <steven.price@xxxxxxx>
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Cc: Zack Rusin <zackr@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mapping_dirty_helpers.c | 34 +++++++++-------------------------
1 file changed, 9 insertions(+), 25 deletions(-)
--- a/mm/mapping_dirty_helpers.c~mm-vmwgfx-simplify-pmd-pud-mapping-dirty-helpers
+++ a/mm/mapping_dirty_helpers.c
@@ -128,19 +128,11 @@ static int wp_clean_pmd_entry(pmd_t *pmd
{
pmd_t pmdval = pmdp_get_lockless(pmd);
- if (!pmd_trans_unstable(&pmdval))
- return 0;
-
- if (pmd_none(pmdval)) {
- walk->action = ACTION_AGAIN;
- return 0;
- }
-
- /* Huge pmd, present or migrated */
- walk->action = ACTION_CONTINUE;
- if (pmd_trans_huge(pmdval) || pmd_devmap(pmdval))
+ /* Do not split a huge pmd, present or migrated */
+ if (pmd_trans_huge(pmdval) || pmd_devmap(pmdval)) {
WARN_ON(pmd_write(pmdval) || pmd_dirty(pmdval));
-
+ walk->action = ACTION_CONTINUE;
+ }
return 0;
}
@@ -156,23 +148,15 @@ static int wp_clean_pmd_entry(pmd_t *pmd
static int wp_clean_pud_entry(pud_t *pud, unsigned long addr, unsigned long end,
struct mm_walk *walk)
{
+#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
pud_t pudval = READ_ONCE(*pud);
- if (!pud_trans_unstable(&pudval))
- return 0;
-
- if (pud_none(pudval)) {
- walk->action = ACTION_AGAIN;
- return 0;
- }
-
-#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
- /* Huge pud */
- walk->action = ACTION_CONTINUE;
- if (pud_trans_huge(pudval) || pud_devmap(pudval))
+ /* Do not split a huge pud */
+ if (pud_trans_huge(pudval) || pud_devmap(pudval)) {
WARN_ON(pud_write(pudval) || pud_dirty(pudval));
+ walk->action = ACTION_CONTINUE;
+ }
#endif
-
return 0;
}
_
Patches currently in -mm which might be from hughd@xxxxxxxxxx are
