From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-170.mta1.migadu.com (out-170.mta1.migadu.com [95.215.58.170]) (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 70FDA35F61A; Mon, 13 Jul 2026 10:24:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783938271; cv=none; b=MlcjUgGuEEUvQojlDITvvhioELKdkkts1yW5+XzxRWVVmCGjmXh2M5Vp119LC/jIxryUo1P9Z258vf9N1k+1BbfT8uF2BcxLSeNs0x/UCCfqG0lc7qW589HTbSIZUyAOGFMyu3Y9W7C7qGKTutkmQgnqp90OGUkOEPG5t8ODYlY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783938271; c=relaxed/simple; bh=N6ENnk3rgY035vjNsHIRv2m6en78KY1ZwtwIFc+ebh8=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=I2r4M/2BhworIZTvl4HegZpZcaobASu4yBBIPFf/vBWGc53Zxk+X9fIhdWvZjL+OL3LU0itwsT7pNdbLMuUXCUcetev5IUZWYTOBxt3QY3yvNwtetwWYWUaeyXqG8A7lFsMvnzpjilkpk5BBbd0xTU1hAeUQY5Gld0A6zwO92GY= 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=uvMmJ6cU; arc=none smtp.client-ip=95.215.58.170 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="uvMmJ6cU" Message-ID: <1bd1dd99-4db0-4120-bebf-b1da42977778@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1783938267; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Nlpe1/nwJgVHs+1CgELsGk74K3Ki4WuxEiQer53NK8w=; b=uvMmJ6cUAyBsmzFEXhT9EaxuwrEH+WOZ9I2vr8S7uIrGuNyoIhqebiAcV8/uYTDFI52Mop rtyUJEmCxdapuezObmHKvTA8N7XA0oUHZ5RTvMJX3BMHFgoH0swoYx44FF89YtuVo3kVxh zW3velkdD7gVnpzhzlfybnpoaCRkLyg= Date: Mon, 13 Jul 2026 18:24:14 +0800 Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Cc: cui.tao@linux.dev, Johannes Weiner , Michal Hocko , Shakeel Butt , Muchun Song , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Guopeng Zhang Subject: Re: [PATCH] mm: memcontrol: factor out memcg kmem uncharge sequence To: Guopeng Zhang , Andrew Morton , Roman Gushchin References: <20260713090304.3015329-1-guopeng.zhang@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Tao Cui In-Reply-To: <20260713090304.3015329-1-guopeng.zhang@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2026/7/13 17:03, Guopeng Zhang 写道: > From: Guopeng Zhang > > The kmem-uncharge sequence (mod_memcg_state(MEMCG_KMEM) + > memcg1_account_kmem + conditional memcg_uncharge) is duplicated verbatim > in obj_cgroup_release() and drain_obj_stock_slot(). Factor it into a > small memcg_uncharge_kmem() helper. The reference get/put stays at the > call sites, as they differ. > > No functional change. Acked-by: Tao Cui > > Signed-off-by: Guopeng Zhang > --- > mm/memcontrol.c | 18 ++++++++++-------- > 1 file changed, 10 insertions(+), 8 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 22f55aeb94f3..86acfe55a201 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -137,6 +137,14 @@ bool mem_cgroup_kmem_disabled(void) > > static void memcg_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages); > > +static void memcg_uncharge_kmem(struct mem_cgroup *memcg, unsigned int nr_pages) > +{ > + mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); > + memcg1_account_kmem(memcg, -nr_pages); > + if (!mem_cgroup_is_root(memcg)) > + memcg_uncharge(memcg, nr_pages); > +} > + > static void obj_cgroup_release(struct percpu_ref *ref) > { > struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt); > @@ -172,10 +180,7 @@ static void obj_cgroup_release(struct percpu_ref *ref) > struct mem_cgroup *memcg; > > memcg = get_mem_cgroup_from_objcg(objcg); > - mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); > - memcg1_account_kmem(memcg, -nr_pages); > - if (!mem_cgroup_is_root(memcg)) > - memcg_uncharge(memcg, nr_pages); > + memcg_uncharge_kmem(memcg, nr_pages); > mem_cgroup_put(memcg); > } > > @@ -3329,10 +3334,7 @@ static void drain_obj_stock_slot(struct obj_stock_pcp *stock, int i) > > memcg = get_mem_cgroup_from_objcg(old); > > - mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); > - memcg1_account_kmem(memcg, -nr_pages); > - if (!mem_cgroup_is_root(memcg)) > - memcg_uncharge(memcg, nr_pages); > + memcg_uncharge_kmem(memcg, nr_pages); > > css_put(&memcg->css); > }