linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
To: Vlastimil Babka <vbabka@suse.cz>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>,
	Christoph Lameter <cl@gentwo.org>,
	David Rientjes <rientjes@google.com>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	Harry Yoo <harry.yoo@oracle.com>,
	linux-mm@kvack.org
Subject: [PATCH v3 10/17] slab: Remove folio references from build_detached_freelist()
Date: Fri, 24 Oct 2025 21:44:25 +0100	[thread overview]
Message-ID: <20251024204434.2461319-11-willy@infradead.org> (raw)
In-Reply-To: <20251024204434.2461319-1-willy@infradead.org>

As with memcg_slab_post_charge(), we save a call to compound_head() for
large kmallocs.  This has a slight change of behaviour in that non-slab,
non-kmalloc pointers will now cause a NULL pointer dereference rather
than a warning.  We could add that back if really needed.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 mm/slub.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 4e282e7782bb..e72016ff0236 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -7244,23 +7244,23 @@ int build_detached_freelist(struct kmem_cache *s, size_t size,
 {
 	int lookahead = 3;
 	void *object;
-	struct folio *folio;
+	struct page *page;
 	size_t same;
 
 	object = p[--size];
-	folio = virt_to_folio(object);
+	page = virt_to_page(object);
 	if (!s) {
 		/* Handle kalloc'ed objects */
-		if (unlikely(!folio_test_slab(folio))) {
-			free_large_kmalloc(&folio->page, object);
+		if (unlikely(PageLargeKmalloc(page))) {
+			free_large_kmalloc(page, object);
 			df->slab = NULL;
 			return size;
 		}
 		/* Derive kmem_cache from object */
-		df->slab = folio_slab(folio);
+		df->slab = page_slab(page);
 		df->s = df->slab->slab_cache;
 	} else {
-		df->slab = folio_slab(folio);
+		df->slab = page_slab(page);
 		df->s = cache_from_obj(s, object); /* Support for memcg */
 	}
 
-- 
2.47.2



  parent reply	other threads:[~2025-10-24 20:44 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-24 20:44 [PATCH v3 00/17] Prepare slab for memdescs Matthew Wilcox (Oracle)
2025-10-24 20:44 ` [PATCH v3 01/17] slab: Reimplement page_slab() Matthew Wilcox (Oracle)
2025-10-27 15:34   ` Vlastimil Babka
2025-10-24 20:44 ` [PATCH v3 02/17] slab: Remove folio references from __ksize() Matthew Wilcox (Oracle)
2025-10-24 20:44 ` [PATCH v3 03/17] slab: Remove folio references in memcg_slab_post_charge() Matthew Wilcox (Oracle)
2025-10-28  6:40   ` Harry Yoo
2025-10-24 20:44 ` [PATCH v3 04/17] slab: Remove folio references in slab alloc/free Matthew Wilcox (Oracle)
2025-10-28  6:22   ` Harry Yoo
2025-10-24 20:44 ` [PATCH v3 05/17] slab: Remove folio references from ___kmalloc_large_node() Matthew Wilcox (Oracle)
2025-10-28  6:24   ` Harry Yoo
2025-10-24 20:44 ` [PATCH v3 06/17] slab: Remove folio references from free_large_kmalloc() Matthew Wilcox (Oracle)
2025-10-28  6:29   ` Harry Yoo
2025-10-28  6:49   ` Harry Yoo
2025-10-24 20:44 ` [PATCH v3 07/17] slab: Remove folio references from kvfree_rcu_cb() Matthew Wilcox (Oracle)
2025-10-24 20:44 ` [PATCH v3 08/17] slab: Remove folio references from kvfree() Matthew Wilcox (Oracle)
2025-10-27 16:58   ` Vlastimil Babka
2025-10-27 21:02     ` Matthew Wilcox
2025-10-24 20:44 ` [PATCH v3 09/17] slab: Remove folio references from __do_krealloc() Matthew Wilcox (Oracle)
2025-10-27 18:01   ` Vlastimil Babka
2025-10-24 20:44 ` Matthew Wilcox (Oracle) [this message]
2025-10-27 18:03   ` [PATCH v3 10/17] slab: Remove folio references from build_detached_freelist() Vlastimil Babka
2025-10-24 20:44 ` [PATCH v3 11/17] slab: Remove dead code from free_large_kmalloc() Matthew Wilcox (Oracle)
2025-10-27 18:04   ` Vlastimil Babka
2025-10-24 20:44 ` [PATCH v3 12/17] slab: Remove folio references from kfree_rcu_sheaf() Matthew Wilcox (Oracle)
2025-10-24 20:44 ` [PATCH v3 13/17] slab: Remove folio references from kfree_nolock() Matthew Wilcox (Oracle)
2025-10-24 20:44 ` [PATCH v3 14/17] usercopy: Remove folio references from check_heap_object() Matthew Wilcox (Oracle)
2025-10-27 18:15   ` Vlastimil Babka
2025-10-24 20:44 ` [PATCH v3 15/17] memcg: Convert mem_cgroup_from_obj_folio() to mem_cgroup_from_obj_slab() Matthew Wilcox (Oracle)
2025-10-27 18:32   ` Vlastimil Babka
2025-10-24 20:44 ` [PATCH v3 16/17] kasan: Remove references to folio in __kasan_mempool_poison_object() Matthew Wilcox (Oracle)
2025-10-27 18:39   ` Vlastimil Babka
2025-10-24 20:44 ` [PATCH v3 17/17] slab: Remove references to folios from virt_to_slab() Matthew Wilcox (Oracle)

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20251024204434.2461319-11-willy@infradead.org \
    --to=willy@infradead.org \
    --cc=akpm@linux-foundation.org \
    --cc=cl@gentwo.org \
    --cc=harry.yoo@oracle.com \
    --cc=linux-mm@kvack.org \
    --cc=rientjes@google.com \
    --cc=roman.gushchin@linux.dev \
    --cc=vbabka@suse.cz \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox