From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f174.google.com (mail-pf1-f174.google.com [209.85.210.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B0EBB136652; Tue, 23 Apr 2024 15:56:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713887802; cv=none; b=O4yFeHgDPT2JJmz/8yLoV8ETvWfepLsB0b6RGQACmK5n3h4AuPRMXucL6+TXIdU/2eswn7FbjUMoBXhtsYEm+o6A4nuWUAyjEdgs5fBmI62EP9bCYS4whecVInUKClbDrdJv8RizhUJ0Hl6Zrn/MoGQpqCPQpybGU807YuR1FGY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713887802; c=relaxed/simple; bh=+WQoZCfvynzpRW6VnCCjpKF3zxAAd2n5DqdreZLhSBk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=G6ZM9Lm7cKa8Zza4xGF6Z2d3RHts1RC0SRpmXUkfqcVsivGmMRhd8HQK89n1cDYj/w24DXGWPqebpTKOEnr5b2qJEOkTfgIcVhvTeL3lMLZojoAIjq7GfL8k6lX6HERb6vVPpSmgO9MlyJi9xP5piRItdNMand4z3BAFQoKzz5E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=MjKYTsb7; arc=none smtp.client-ip=209.85.210.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="MjKYTsb7" Received: by mail-pf1-f174.google.com with SMTP id d2e1a72fcca58-6ed2170d89fso4457836b3a.1; Tue, 23 Apr 2024 08:56:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1713887800; x=1714492600; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=TiXJwUhPMkjGHKs13WSq0NGz2KDz4IaigXpr6ZbxkHA=; b=MjKYTsb71fwZou2p4aMhS2LlO4+ZSDQvRmu/aZAZ0sFSRnzueGJfp6qIk30CCF3Nyn ME90yAMNodEr2uiPjAGV0OKP/5SJCiOvBN8bhDD/9LeHgYPP8ixbn9zcC/wV2kx16EMw LdD4zaPQgABL6RLAwKuKeby9pVaPhUHuSZv93W8BskSLL4dBtvi2hfLSsWFN+JA5DWdX hZHnNpd8bY6iS3xV0WFLUt6DwbDx7nrBOf4BgrsusCdXqLwL5idHl4JFtGUVSrKZ/GpW O7ed9xw4g1xkyQJuDUBh02AtO1IjM1j+mvj2IHDnqGw7kxbK+h+yROiVbiv8ct1/k2OG dyVg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713887800; x=1714492600; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=TiXJwUhPMkjGHKs13WSq0NGz2KDz4IaigXpr6ZbxkHA=; b=m5BM8yHerAKawoqDFqtXlYMTBnPrXXzA/6CIzchlLh/2uWhh0v7Oc1e0CTppTjTik7 t61OmLAVzzc0UvEKgkMp6xP+p1j49Rujo11/l3gKKD2LEumvwuArIR3+YAvJLx1BNM5j a3Tcmu9v0wmehJpOMAZj4vYZc9jhQh54mIcNO78xszmifvs0QFdliZJBCSyN2Xizo0pd L9gQ/C6Y+v95LDLh1/N52ECr0BtG/ljYPK0TrMSIr3uzK3ACj6LU7fEYIIDGDn2x6pSI 97WFiVwgdp9xA8HmKO1w+PHDvJtaFLSeIoyyWdYhMN7uxdLEJJ15ixpnh0DzlxgikPZq LnJg== X-Forwarded-Encrypted: i=1; AJvYcCV2MmjmRU/kTtm2AVZwAr48fvSeCRuBNpzpiz8ELfDrLiZl4Ty1Vb9uODaWMc47laTC5vI68mAqlMNl49e9HMrTdR+SmyqHHR6Bjvsqv6YG8Wyow2qgQ4s3Gzlg0RE3JHxeWBlFzOSO8z0T46p2T4h4mA66f74njH9Gts8RD6Uf4Jlp3fc= X-Gm-Message-State: AOJu0YwaLXFkjB9uycPERVQ0VCdh1Zy4DwazXyb15MIMhw19b35JgCL7 MNeKV80Jfnmo2M0a0n6O3KhPVkEKLdmAjwDsyda4BuIfAKxg1uNf X-Google-Smtp-Source: AGHT+IEjl28DHNnTcDOKcrrQgkmsbyO0K1hBgAt0eVjjLJ03dT44w2VLFfYWunJLIKjDEVbIXfLeGQ== X-Received: by 2002:a05:6a21:2d8c:b0:1a3:a821:f297 with SMTP id ty12-20020a056a212d8c00b001a3a821f297mr4606950pzb.2.1713887799820; Tue, 23 Apr 2024 08:56:39 -0700 (PDT) Received: from localhost ([2620:10d:c090:400::5:6f51]) by smtp.gmail.com with ESMTPSA id gs9-20020a056a004d8900b006e694719fa0sm10119667pfb.147.2024.04.23.08.56.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Apr 2024 08:56:39 -0700 (PDT) Sender: Tejun Heo Date: Tue, 23 Apr 2024 05:56:38 -1000 From: Tejun Heo To: Jan Kara Cc: Xiu Jianfeng , viro@zeniv.linux.org.uk, brauner@kernel.org, lizefan.x@bytedance.com, hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH -next] cgroup: Introduce css_is_online() helper Message-ID: References: <20240420094428.1028477-1-xiujianfeng@huawei.com> <20240423134923.osuljlalsd27awz3@quack3> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240423134923.osuljlalsd27awz3@quack3> Hello, On Tue, Apr 23, 2024 at 03:49:23PM +0200, Jan Kara wrote: > On Sat 20-04-24 09:44:28, Xiu Jianfeng wrote: > > Introduce css_is_online() helper to test if whether the specified > > css is online, avoid testing css.flags with CSS_ONLINE directly > > outside of cgroup.c. > > > > Signed-off-by: Xiu Jianfeng > > Looks good. Feel free to add: > > Reviewed-by: Jan Kara I'm a bit skeptical about these trivial helpers. If the test is something more involved or has complications which need documentation (e.g. regarding synchronization and what not), the helper would be useful even if it's just as a place to centrally document what's going on. However, here, it's just testing one flag and I'm not sure what benefits the helper brings. Thanks. -- tejun