From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72982C25B4F for ; Tue, 7 May 2024 13:31:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0AA6D6B008A; Tue, 7 May 2024 09:31:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0343E6B008C; Tue, 7 May 2024 09:31:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E176F6B0092; Tue, 7 May 2024 09:31:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id C38826B008A for ; Tue, 7 May 2024 09:31:46 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 576D441378 for ; Tue, 7 May 2024 13:31:46 +0000 (UTC) X-FDA: 82091687412.26.1F5E258 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf15.hostedemail.com (Postfix) with ESMTP id C5813A002E for ; Tue, 7 May 2024 13:31:43 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=none; spf=pass (imf15.hostedemail.com: domain of xiujianfeng@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=xiujianfeng@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1715088704; h=from:from:sender: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=wHomnQPsq1BIB95P/lqOebqIn+KzAQbfhmlEwjWgSLE=; b=nSwgk9oy2jvq2WQxtuYCFeSzM+kWIm65HMvYutryOmYUpRmB7UPh+LB9z06eUQNQ6toRRe maqGmYnfph9RE2gsiFGniMIELNgK4lWBECuizhy1L13n3hKW3MEXH7Sc11kXOrTcSVoBG+ FHDaoE6FLzImUC/MfuDHN868MRgjJzY= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=none; spf=pass (imf15.hostedemail.com: domain of xiujianfeng@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=xiujianfeng@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1715088704; a=rsa-sha256; cv=none; b=hQt+U+q0xIDga8Ucvm2jfKlJE/W2gCc7/N51yVQzWDfAobKNj4tQufjG3mwTbqHX/6GgzI e1vb6Dqmu8wgk26JsuyhRf2XjZm5MMZWNONx4J+zFvl8sXCJWTuZeqdsPaaNmZkTwWaNrb mVp7gnGJlJ0SYZQzyB89nYODBY4Tv4c= Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4VYfH32hTsztT4H; Tue, 7 May 2024 21:28:15 +0800 (CST) Received: from dggpeml500023.china.huawei.com (unknown [7.185.36.114]) by mail.maildlp.com (Postfix) with ESMTPS id 7EE801800C9; Tue, 7 May 2024 21:31:40 +0800 (CST) Received: from [10.67.110.112] (10.67.110.112) by dggpeml500023.china.huawei.com (7.185.36.114) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Tue, 7 May 2024 21:31:40 +0800 Message-ID: <10484734-13e6-4c56-d7dc-6c4cf74bd8de@huawei.com> Date: Tue, 7 May 2024 21:31:39 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.5.1 Subject: Re: [PATCH v2 -next] mm: memcg: make alloc_mem_cgroup_per_node_info() return bool Content-Language: en-US To: Michal Hocko CC: , , , , , , , References: <20240507110832.1128370-1-xiujianfeng@huawei.com> From: xiujianfeng In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.110.112] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpeml500023.china.huawei.com (7.185.36.114) X-Stat-Signature: omod3r8udqqsh51naxr45kcbj4qeu3m8 X-Rspam-User: X-Rspamd-Queue-Id: C5813A002E X-Rspamd-Server: rspam05 X-HE-Tag: 1715088703-409976 X-HE-Meta: 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 g3YJ/njv r0v/ns2Mf6BiwAjCM9jamTcFtHNCfPmMukMWoHTdhqC5i+GaIPsEtP1OaiorPO4jv5oU7idmATTXHc4TYseNeDvQTQkDjppb+nz+We1SQmly5h/5zvz9Af7zEMtEIpK/+rDjrfoG9G3jUIx4QPlh8F1mundMaTTgjDZENCQ+KMrt5Gxncdv1kGltLwTxKYlVU+3FYspLRLdDGXUj1yrZ7y89O7etf+A7VA/JkqNjWrWaUA9sZq39AiTiIHPBmKIqUhDD5bfOAAntigGI= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2024/5/7 21:10, Michal Hocko wrote: > On Tue 07-05-24 11:08:32, Xiu Jianfeng wrote: >> Currently alloc_mem_cgroup_per_node_info() returns 1 if failed, >> make it return bool, false for failure and true for success. > > This describes what the patch does rather than why it is doing that. > The former is clear from the diff while the motivation for this change > is unclear. I would propose something like: > > alloc_mem_cgroup_per_node_info() returns int that doesn't map to any > errno error code. The only existing caller doesn't really need an error > code so change the the function to return bool (true on success) because > this is slightly less confusing and more consistent with the other code. Thanks, it looks much better now. > >> Signed-off-by: Xiu Jianfeng > > With changelog clarified feel free to add > Acked-by: Michal Hocko > >> --- >> mm/memcontrol.c | 10 +++++----- >> 1 file changed, 5 insertions(+), 5 deletions(-) >> >> diff --git a/mm/memcontrol.c b/mm/memcontrol.c >> index d11536ef59ef..69d70feb8e68 100644 >> --- a/mm/memcontrol.c >> +++ b/mm/memcontrol.c >> @@ -5653,13 +5653,13 @@ struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino) >> } >> #endif >> >> -static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) >> +static bool alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) >> { >> struct mem_cgroup_per_node *pn; >> >> pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, node); >> if (!pn) >> - return 1; >> + return false; >> >> pn->lruvec_stats = kzalloc_node(sizeof(struct lruvec_stats), GFP_KERNEL, >> node); >> @@ -5675,11 +5675,11 @@ static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) >> pn->memcg = memcg; >> >> memcg->nodeinfo[node] = pn; >> - return 0; >> + return true; >> fail: >> kfree(pn->lruvec_stats); >> kfree(pn); >> - return 1; >> + return false; >> } >> >> static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) >> @@ -5751,7 +5751,7 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent) >> } >> >> for_each_node(node) >> - if (alloc_mem_cgroup_per_node_info(memcg, node)) >> + if (!alloc_mem_cgroup_per_node_info(memcg, node)) >> goto fail; >> >> if (memcg_wb_domain_init(memcg, GFP_KERNEL)) >> -- >> 2.34.1 >> >