+ slub-remove-use-of-page-flags.patch added to mm-unstable branch

+ slub-remove-use-of-page-flags.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: slub: remove use of page->flags
has been added to the -mm mm-unstable branch.  Its filename is
     slub-remove-use-of-page-flags.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/slub-remove-use-of-page-flags.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: slub: remove use of page->flags
Date: Tue, 26 Mar 2024 17:10:30 +0000

Use slub->__page_flags instead.  We can also remove the assertion that
it's not a tail page as struct slab never points to a tail page.

Link: https://lkml.kernel.org/r/20240326171045.410737-9-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/slub.c |   10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

--- a/mm/slub.c~slub-remove-use-of-page-flags
+++ a/mm/slub.c
@@ -616,18 +616,12 @@ slub_set_cpu_partial(struct kmem_cache *
  */
 static __always_inline void slab_lock(struct slab *slab)
 {
-	struct page *page = slab_page(slab);
-
-	VM_BUG_ON_PAGE(PageTail(page), page);
-	bit_spin_lock(PG_locked, &page->flags);
+	bit_spin_lock(PG_locked, &slab->__page_flags);
 }
 
 static __always_inline void slab_unlock(struct slab *slab)
 {
-	struct page *page = slab_page(slab);
-
-	VM_BUG_ON_PAGE(PageTail(page), page);
-	bit_spin_unlock(PG_locked, &page->flags);
+	bit_spin_unlock(PG_locked, &slab->__page_flags);
 }
 
 static inline bool
_

Patches currently in -mm which might be from willy@infradead.org are

mm-always-initialise-folio-_deferred_list.patch
mm-create-folio_flag_false-and-folio_type_ops-macros.patch
mm-remove-folio_prep_large_rmappable.patch
mm-support-page_mapcount-on-page_has_type-pages.patch
mm-turn-folio_test_hugetlb-into-a-pagetype.patch
mm-turn-folio_test_hugetlb-into-a-pagetype-fix.patch
mm-remove-a-call-to-compound_head-from-is_page_hwpoison.patch
mm-free-up-pg_slab.patch
mm-free-up-pg_slab-fix.patch
mm-improve-dumping-of-mapcount-and-page_type.patch
hugetlb-remove-mention-of-destructors.patch
sh-remove-use-of-pg_arch_1-on-individual-pages.patch
xtensa-remove-uses-of-pg_arch_1-on-individual-pages.patch
mm-make-page_ext_get-take-a-const-argument.patch
mm-make-folio_test_idle-and-folio_test_young-take-a-const-argument.patch
mm-make-is_free_buddy_page-take-a-const-argument.patch
mm-make-page_mapped-take-a-const-argument.patch
mm-convert-arch_clear_hugepage_flags-to-take-a-folio.patch
slub-remove-use-of-page-flags.patch
remove-references-to-page-flags-in-documentation.patch
proc-rewrite-stable_page_flags.patch