From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-173.mta0.migadu.com (out-173.mta0.migadu.com [91.218.175.173]) (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 196A647799B for ; Fri, 6 Mar 2026 20:29:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772828991; cv=none; b=NPjKdgy0x/1UpkNQd4301x4ZeXqc5gf7PBuISQUWLDp+xJF6+UKSpIfoQyKcaLd1Ykd5lm5OwGXsJvKNGgBz3idvFNdsTZyoS8+qfjH8jSPJi7+6HRKGozPrgB9jEi2r+1AeCuCXyRysCeClYEPqeZiDeHdFCu23uovnFHmOsX0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772828991; c=relaxed/simple; bh=rFfmioNiorqkmxbTrUeBgC8NnB58UG6HTHT7bTr4Blo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Z/HR9ygWRqu+wV8IsslWnEU+84es3JbaGMUYoZ0clh6VT4I6D8k6oYEpdNYzVQy2dqoYtWLlAbJT7GUeMJ31hsy0/5ZPFO6aQlApz6Yu7KpyEkHc5+d0BaKIVvvakTvm46MgoPYoVokCto14CaeHj7uRqABjvKfBeNXj1/lcwCQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=iupAZja8; arc=none smtp.client-ip=91.218.175.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="iupAZja8" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1772828978; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xu4FOpsB3tis67Vr0ogStH5duKlNRv21WglBri7UTcs=; b=iupAZja8wy6lFb/pwYfc8nhuO+aJSry5Kzt+7aHHLHQlaMXK2PAsZMFNNd66go/2W6Kkwe vdSCNOLTyQowEMIgGXwIyWRJErAzaAgNXx4GOqe/oeRcXdJ66tdgH5XHnVRTlmSidJ3kyS lzPKFMCdB6Vy+1HRz3vUG4R4h/6qZ20= From: Usama Arif To: Qi Zheng Cc: Usama Arif , hannes@cmpxchg.org, hughd@google.com, mhocko@suse.com, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, david@kernel.org, lorenzo.stoakes@oracle.com, ziy@nvidia.com, harry.yoo@oracle.com, yosry.ahmed@linux.dev, imran.f.khan@oracle.com, kamalesh.babulal@oracle.com, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, chenridong@huaweicloud.com, mkoutny@suse.com, akpm@linux-foundation.org, hamzamahfooz@linux.microsoft.com, apais@linux.microsoft.com, lance.yang@linux.dev, bhe@redhat.com, usamaarif642@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Qi Zheng Subject: Re: [PATCH v6 31/33] mm: memcontrol: convert objcg to be per-memcg per-node type Date: Fri, 6 Mar 2026 12:29:28 -0800 Message-ID: <20260306202931.3878822-1-usama.arif@linux.dev> In-Reply-To: <56c04b1c5d54f75ccdc12896df6c1ca35403ecc3.1772711148.git.zhengqi.arch@bytedance.com> References: Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT On Thu, 5 Mar 2026 19:52:49 +0800 Qi Zheng wrote: > From: Qi Zheng > > Convert objcg to be per-memcg per-node type, so that when reparent LRU > folios later, we can hold the lru lock at the node level, thus avoiding > holding too many lru locks at once. > > Signed-off-by: Qi Zheng > Acked-by: Shakeel Butt > --- > include/linux/memcontrol.h | 23 +++++------ > include/linux/sched.h | 2 +- > mm/memcontrol.c | 79 +++++++++++++++++++++++--------------- > 3 files changed, 62 insertions(+), 42 deletions(-) > [...] > @@ -4087,7 +4100,13 @@ static int mem_cgroup_css_online(struct cgroup_subsys_state *css) > xa_store(&mem_cgroup_private_ids, memcg->id.id, memcg, GFP_KERNEL); > > return 0; > -free_shrinker: > +free_objcg: > + for_each_node(nid) { > + struct mem_cgroup_per_node *pn = memcg->nodeinfo[nid]; > + > + if (pn && pn->orig_objcg) > + obj_cgroup_put(pn->orig_objcg); Is it possible that you might call obj_cgroup_put twice on the same cgroup? If css_create fails, css_free_rwork_fn is queued, which ends up calling mem_cgroup_css_free which calls obj_cgroup_put again? Maybe adding pn->orig_objcg = NULL overhere after obj_cgroup_put is enough to prevent the double put from causing issues? > + } > free_shrinker_info(memcg); > offline_kmem: > memcg_offline_kmem(memcg); > -- > 2.20.1 > >