From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 74B4842A17B; Mon, 20 Jul 2026 14:16:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784557008; cv=none; b=pfrskSaKJP4BMhWN9j4u73Uu+xMNYcmRQhmh/qOVcIRRPnwPqrJH9OzQM3KTuHvOcDjAaEyeDoDZjAuQgYtaSnUoZ0iHBTsZrq+5MMqzpeV9aI32x8AK+htubPc9QXflGQg4Ca9NIkhvFaZqNBRLX+U76MK0vkIAo2VdfrTZADU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784557008; c=relaxed/simple; bh=mcQgvQ3H084hVOKFHe4mvrHFvcTIirhGDX/vYCPlAwk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Z9nrDfzXovZhytBqsEvIzEq9OmruWqahVowH7G6pJsqWlEr8Kl8PNJO+fE+wv0mPc943GCX9uF4Ca3tHylpG+XnsuMzeCVTNr3FRP/zasSSlNSGxzcQ0J44mKo/BpW+uxsIw83YAHrFPv29s6eppldGqJYjDGoKjhuqYujeHRgU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=O6IlCXMd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="O6IlCXMd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D66F1F00A3A; Mon, 20 Jul 2026 14:16:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784557007; bh=D3U54YmCRY/GBvsj3bANv9/dOilD8BR4I8e1Q/zY4xQ=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=O6IlCXMdef44TD7zJDcvT/iuRPSZckHKHRWd2siui/LxQAjoo18KmQMbMT4tgXl1Q 1X5kY0W9M7JYIxRhNTGXKCEnC5UX2HkNMjlBvC6arD+edzA/ECMxxPXTLp8X49UX1X 9rG1xY2R069IV3CexOp8B1LPpZtquCZu49DQdp5FI72jor3t6olgYxL3klKFc+7Ivn sJgOjcCx8hnR7a4ZBe+GPek4JDGE2hScWhpZKI6dU+iwzwoyU0aCcaxJf2q5uYwF62 cJ4jGLvHqKi94GnJMWMn19jujSokl6DzGH4mCi+hjXVb9Wyxydr1tXjstWaMdzyhJt BbwufI9yG6TWA== From: "Vlastimil Babka (SUSE)" Date: Mon, 20 Jul 2026 16:16:20 +0200 Subject: [PATCH v2 06/13] mm/slab: abstract slabobj_ext.objcg access Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260720-b4-objext_split-v2-6-2fa7c6f60dbe@kernel.org> References: <20260720-b4-objext_split-v2-0-2fa7c6f60dbe@kernel.org> In-Reply-To: <20260720-b4-objext_split-v2-0-2fa7c6f60dbe@kernel.org> To: Harry Yoo , Suren Baghdasaryan Cc: Hao Li , Shakeel Butt , Alexander Potapenko , Marco Elver , Andrew Morton , Christoph Lameter , David Rientjes , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, "Vlastimil Babka (SUSE)" X-Mailer: b4 0.15.2 In preparation for changes to the structure, abstract getting and setting the objcg field with slab_obj_ext_objcg() and slab_obj_ext_set_objcg(). Rename the field to _objcg to make an unexpected direct access a compile error. No functional change intended. Signed-off-by: Vlastimil Babka (SUSE) --- mm/kfence/core.c | 2 +- mm/memcontrol.c | 14 ++++++++------ mm/slab.h | 15 ++++++++++++++- mm/slub.c | 2 +- 4 files changed, 24 insertions(+), 9 deletions(-) diff --git a/mm/kfence/core.c b/mm/kfence/core.c index 6577bd76954e..05b5482c8150 100644 --- a/mm/kfence/core.c +++ b/mm/kfence/core.c @@ -1249,7 +1249,7 @@ void __kfence_free(void *addr) struct kfence_metadata *meta = addr_to_metadata((unsigned long)addr); #ifdef CONFIG_MEMCG - KFENCE_WARN_ON(meta->obj_exts.objcg); + KFENCE_WARN_ON(slab_obj_ext_objcg(&meta->obj_exts)); #endif /* * If the objects of the cache are SLAB_TYPESAFE_BY_RCU, defer freeing diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 4e427286a88a..cb1e97b4edc1 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2865,6 +2865,7 @@ struct mem_cgroup *mem_cgroup_from_obj_slab(struct slab *slab, void *p) */ unsigned long obj_exts; struct slabobj_ext *obj_ext; + struct obj_cgroup *objcg; obj_exts = slab_obj_exts(slab); if (!obj_exts) @@ -2872,9 +2873,8 @@ struct mem_cgroup *mem_cgroup_from_obj_slab(struct slab *slab, void *p) get_slab_obj_exts(obj_exts); obj_ext = slab_obj_ext(slab->slab_cache, slab, obj_exts, p); - if (obj_ext->objcg) { - struct obj_cgroup *objcg = obj_ext->objcg; - + objcg = slab_obj_ext_objcg(obj_ext); + if (objcg) { put_slab_obj_exts(obj_exts); return obj_cgroup_memcg(objcg); } @@ -3614,8 +3614,10 @@ bool __memcg_slab_post_alloc_hook(struct kmem_cache *s, struct list_lru *lru, obj_exts = slab_obj_exts(slab); get_slab_obj_exts(obj_exts); obj_ext = slab_obj_ext(s, slab, obj_exts, p[i]); + obj_cgroup_get(objcg); - obj_ext->objcg = objcg; + slab_obj_ext_set_objcg(obj_ext, objcg); + put_slab_obj_exts(obj_exts); } @@ -3633,11 +3635,11 @@ void __memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, struct obj_stock_pcp *stock; obj_ext = slab_obj_ext(s, slab, obj_exts, p[i]); - objcg = obj_ext->objcg; + objcg = slab_obj_ext_objcg(obj_ext); if (!objcg) continue; - obj_ext->objcg = NULL; + slab_obj_ext_set_objcg(obj_ext, NULL); stock = trylock_stock(); __refill_obj_stock(objcg, stock, obj_size, true); diff --git a/mm/slab.h b/mm/slab.h index 64cec02b5016..1d1771f97aca 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -555,7 +555,7 @@ static inline bool need_kmalloc_no_objext(void) */ struct slabobj_ext { #ifdef CONFIG_MEMCG - struct obj_cgroup *objcg; + struct obj_cgroup *_objcg; #endif #ifdef CONFIG_MEM_ALLOC_PROFILING union codetag_ref ref; @@ -662,6 +662,19 @@ slab_obj_ext(struct kmem_cache *s, struct slab *slab, unsigned long obj_exts, return kasan_reset_tag(obj_ext); } +#ifdef CONFIG_MEMCG +static inline struct obj_cgroup *slab_obj_ext_objcg(struct slabobj_ext *obj_ext) +{ + return obj_ext->_objcg; +} + +static inline void slab_obj_ext_set_objcg(struct slabobj_ext *obj_ext, + struct obj_cgroup *objcg) +{ + obj_ext->_objcg = objcg; +} +#endif + int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s, gfp_t gfp, unsigned int alloc_flags); diff --git a/mm/slub.c b/mm/slub.c index aa99d7eb6a4d..f2ffadde879d 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2529,7 +2529,7 @@ bool memcg_slab_post_charge(void *p, gfp_t flags) if (obj_exts) { get_slab_obj_exts(obj_exts); obj_ext = slab_obj_ext(s, slab, obj_exts, p); - if (unlikely(obj_ext->objcg)) { + if (unlikely(slab_obj_ext_objcg(obj_ext))) { put_slab_obj_exts(obj_exts); return true; } -- 2.55.0