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Mon, 27 Jun 2022 02:07:22 -0700 (PDT) Date: Mon, 27 Jun 2022 18:07:20 +0900 From: Tejun Heo To: Vasily Averin Cc: Shakeel Butt , Roman Gushchin , Michal =?iso-8859-1?Q?Koutn=FD?= , Michal Hocko , Zefan Li , Johannes Weiner , kernel@openvz.org, linux-kernel@vger.kernel.org, Andrew Morton , linux-mm@kvack.org, Vlastimil Babka , Muchun Song , cgroups@vger.kernel.org Subject: Re: [PATCH cgroup] cgroup: set the correct return code if hierarchy limits are reached Message-ID: References: <186d5b5b-a082-3814-9963-bf57dfe08511@openvz.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656320844; a=rsa-sha256; cv=none; b=VROJnNB6jHNncW7Zp85buFh1ah+sdMnk4hbY+GStsY6IRiCooeGy9JAr6is4lWooZKvaOt XhR4Svprvrbv8h86kUSjZea4sjKIToJ6FLilgdbG1UlhYDnH3j6O6XaTWcTgWWx7Ee/fI2 BnLxgTZQsAU+YIgOveMsLP2/aRAsdqg= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=fQ6t0azw; 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dmarc=fail reason="SPF not aligned (relaxed), DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=pass (imf28.hostedemail.com: domain of htejun@gmail.com designates 209.85.210.172 as permitted sender) smtp.mailfrom=htejun@gmail.com X-HE-Tag: 1656320843-976731 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: On Mon, Jun 27, 2022 at 05:12:55AM +0300, Vasily Averin wrote: > When cgroup_mkdir reaches the limits of the cgroup hierarchy, it should > not return -EAGAIN, but instead react similarly to reaching the global > limit. While I'm not necessarily against this change, I find the rationale to be somewhat lacking. Can you please elaborate why -ENOSPC is the right one while -EAGAIN is incorrect? Thanks. -- tejun