+ mm-slub-fix-incorrect-memcg-slab-count-for-bulk-free.patch added to -mm tree

+ mm-slub-fix-incorrect-memcg-slab-count-for-bulk-free.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm, slub: fix incorrect memcg slab count for bulk free
has been added to the -mm tree.  Its filename is
     mm-slub-fix-incorrect-memcg-slab-count-for-bulk-free.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-slub-fix-incorrect-memcg-slab-count-for-bulk-free.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-slub-fix-incorrect-memcg-slab-count-for-bulk-free.patch

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next and is updated
there every 3-4 working days

------------------------------------------------------
From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm, slub: fix incorrect memcg slab count for bulk free

kmem_cache_free_bulk() will call memcg_slab_free_hook() for all objects
when doing bulk free.  So we shouldn't call memcg_slab_free_hook() again
for bulk free to avoid incorrect memcg slab count.

Link: https://lkml.kernel.org/r/20210916123920.48704-6-linmiaohe@huawei.com
Fixes: d1b2cf6cb84a ("mm: memcg/slab: uncharge during kmem_cache_free_bulk()")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Bharata B Rao <bharata@linux.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Faiyaz Mohammed <faiyazm@codeaurora.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/slub.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/mm/slub.c~mm-slub-fix-incorrect-memcg-slab-count-for-bulk-free
+++ a/mm/slub.c
@@ -3420,7 +3420,9 @@ static __always_inline void do_slab_free
 	struct kmem_cache_cpu *c;
 	unsigned long tid;
 
-	memcg_slab_free_hook(s, &head, 1);
+	/* memcg_slab_free_hook() is already called for bulk free. */
+	if (!tail)
+		memcg_slab_free_hook(s, &head, 1);
 redo:
 	/*
 	 * Determine the currently cpus per cpu slab.
_

Patches currently in -mm which might be from linmiaohe@huawei.com are

mm-slub-fix-two-bugs-in-slab_debug_trace_open.patch
mm-slub-fix-mismatch-between-reconstructed-freelist-depth-and-cnt.patch
mm-slub-fix-potential-memoryleak-in-kmem_cache_open.patch
mm-slub-fix-potential-use-after-free-in-slab_debugfs_fops.patch
mm-slub-fix-incorrect-memcg-slab-count-for-bulk-free.patch
mm-page_allocc-remove-meaningless-vm_bug_on-in-pindex_to_order.patch
mm-page_allocc-simplify-the-code-by-using-macro-k.patch
mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk.patch
mm-page_allocc-use-helper-function-zone_spans_pfn.patch
mm-page_allocc-avoid-allocating-highmem-pages-via-alloc_pages_exact.patch
mm-page_isolation-fix-potential-missing-call-to-unset_migratetype_isolate.patch
mm-page_isolation-guard-against-possible-putback-unisolated-page.patch
mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch
mm-zsmallocc-close-race-window-between-zs_pool_dec_isolated-and-zs_unregister_migration.patch
mm-zsmallocc-combine-two-atomic-ops-in-zs_pool_dec_isolated.patch