From: Usama Arif <usamaarif642@gmail.com>
Date: Fri, 23 May 2025 16:52:40 +0000 (+0100)
Subject: mm: slub: only warn once when allocating slab obj extensions fails
X-Git-Tag: v6.16-rc1~51^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=354ad60e123dad8e231e7443735020806f3c57d0;p=thirdparty%2Flinux.git

mm: slub: only warn once when allocating slab obj extensions fails

In memory bound systems, a large number of warnings for failing this
allocation repeatedly may mask any real issues in the system
during memory pressure being reported in dmesg. Change this to
warning only once.

Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Reported-by: Vlad Poenaru <vlad.wing@gmail.com>
Closes: https://lore.kernel.org/all/17fab2d6-5a74-4573-bcc3-b75951508f0a@gmail.com/
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---

diff --git a/mm/slub.c b/mm/slub.c
index 566eb8b8282d2..cf36373242435 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2102,10 +2102,11 @@ prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
 
 	slab = virt_to_slab(p);
 	if (!slab_obj_exts(slab) &&
-	    WARN(alloc_slab_obj_exts(slab, s, flags, false),
-		 "%s, %s: Failed to create slab extension vector!\n",
-		 __func__, s->name))
+	    alloc_slab_obj_exts(slab, s, flags, false)) {
+		pr_warn_once("%s, %s: Failed to create slab extension vector!\n",
+			     __func__, s->name);
 		return NULL;
+	}
 
 	return slab_obj_exts(slab) + obj_to_index(s, slab, p);
 }