The patch titled
Subject: mm/huge_memory: remove stale locking logic from __split_huge_pmd()
has been removed from the -mm tree. Its filename was
mm-huge_memory-remove-stale-locking-logic-from-__split_huge_pmd.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/huge_memory: remove stale locking logic from __split_huge_pmd()
Let's remove the stale logic that was required for reuse_swap_page().
[akpm@xxxxxxxxxxxxxxxxxxxx: simplification, per Yang Shi]
Link: https://lkml.kernel.org/r/20220131162940.210846-10-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Don Dutile <ddutile@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Liang Zhang <zhangliang5@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 40 ++++------------------------------------
1 file changed, 4 insertions(+), 36 deletions(-)
--- a/mm/huge_memory.c~mm-huge_memory-remove-stale-locking-logic-from-__split_huge_pmd
+++ a/mm/huge_memory.c
@@ -2133,8 +2133,6 @@ void __split_huge_pmd(struct vm_area_str
{
spinlock_t *ptl;
struct mmu_notifier_range range;
- bool do_unlock_folio = false;
- pmd_t _pmd;
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm,
address & HPAGE_PMD_MASK,
@@ -2153,42 +2151,12 @@ void __split_huge_pmd(struct vm_area_str
goto out;
}
-repeat:
- if (pmd_trans_huge(*pmd)) {
- if (!folio) {
- folio = page_folio(pmd_page(*pmd));
- /*
- * An anonymous page must be locked, to ensure that a
- * concurrent reuse_swap_page() sees stable mapcount;
- * but reuse_swap_page() is not used on shmem or file,
- * and page lock must not be taken when zap_pmd_range()
- * calls __split_huge_pmd() while i_mmap_lock is held.
- */
- if (folio_test_anon(folio)) {
- if (unlikely(!folio_trylock(folio))) {
- folio_get(folio);
- _pmd = *pmd;
- spin_unlock(ptl);
- folio_lock(folio);
- spin_lock(ptl);
- if (unlikely(!pmd_same(*pmd, _pmd))) {
- folio_unlock(folio);
- folio_put(folio);
- folio = NULL;
- goto repeat;
- }
- folio_put(folio);
- }
- do_unlock_folio = true;
- }
- }
- } else if (!(pmd_devmap(*pmd) || is_pmd_migration_entry(*pmd)))
- goto out;
- __split_huge_pmd_locked(vma, pmd, range.start, freeze);
+ if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd) ||
+ is_pmd_migration_entry(*pmd))
+ __split_huge_pmd_locked(vma, pmd, range.start, freeze);
+
out:
spin_unlock(ptl);
- if (do_unlock_folio)
- folio_unlock(folio);
/*
* No need to double call mmu_notifier->invalidate_range() callback.
* They are 3 cases to consider inside __split_huge_pmd_locked():
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
