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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 736E8C9832F for ; Sat, 26 Sep 2026 17:39:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Date:References:In-Reply-To: Subject:Cc:To:From:Message-ID:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=XhgrofmQAGQvZgR98O4k+vp88XndiOafP36SFSUFMyM=; b=RmMazG9md2tH9zW3lQKrVW3oGS z4UPkb/8U16Vy7dsuxmXio+KZSF/1rdmIjKsWy2dina3B4OlTOTtQ9Qct9jDIfUkvjLLTGWY/Kj8l d5Nb0Zme6gBOMhy7I9Ba79gy5MVvEldzwfEGWyZw+Wa5xPaA623cqxO7FiC9AmojKGkgShQtF+3hp VK654wTf+wb82nzy5YsDfPYLSz43Eb/Zl7/oN9N4cN3njTWQeHyvhDjvkPTDncYvBMUenaew40ViF Zijjd5gNVm8MNzERwmilPeKSj9jYWcmNms3QmVmSWvTqxMcPyomx/otfimzS2TOEZg+6kStj+x3gQ VjjM6yVw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xAWNN-0000000FgdG-0E5n; Sat, 26 Sep 2026 17:39:53 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xAWNL-0000000FgdA-0mpw for linux-nvme@lists.infradead.org; Sat, 26 Sep 2026 17:39:52 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 5D9726020C; Sat, 26 Sep 2026 17:39:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DEA061F000FF; Sat, 26 Sep 2026 17:39:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790444390; bh=XhgrofmQAGQvZgR98O4k+vp88XndiOafP36SFSUFMyM=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=mkZGht7x3yNd3LS6HcTIumQBc4oHtTr5FsserxdVmDrHPqDgV8QzPEWdXhecPQEVC zerj8jXPhpNaPkGzeBDimp4zBwy5xgzypxKNEccZaw0bOqUBWM9LbygLoHxKNDvttw /l1lvQHtq/7eFI85v9XQBaT5s6PRIDG7FOT9/4S7vzAMeP4uSg/Ua67JbX5O8nAiWf fvUinYlzmmXHVvzrD6twYYzeMHf0DZCUjEJfFYI75FeqNDyUkVDWWdPOqn88LreKCc orZhLzHyPBAV5agnTHP7+Nncgro8gykxG4ezRsaMwbqPxeIKXgnWIUugzh0Mv8nDRx gBV+bw0LVQYIg== Message-ID: <2edc9a06c00cc96958723d0e09803104@kernel.org> From: Tejun Heo To: Peng Yu Cc: Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni , Johannes Weiner , =?UTF-8?Q?Michal_Koutn=C3=BD?= , Josef Bacik , Jens Axboe , Maurizio Lombardi , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 1/2] cgroup: export cgroup_e_css() In-Reply-To: <20260926063328.257023-2-yupeng0921@gmail.com> References: <20260926063328.257023-1-yupeng0921@gmail.com> <20260926063328.257023-2-yupeng0921@gmail.com> Date: Sat, 26 Sep 2026 07:38:12 -1000 X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org Hello, Peng. On Fri, Sep 25, 2026 at 11:33:27PM -0700, Peng Yu wrote: > The nvmet invokes the cgroup_e_css for each bio and under > the rcu protection. cgroup_e_css() walks up the hierarchy to find the effective css, and I don't think we want to do that on every IO. Can you update cgroup core to track the effective css in each cgroup and make cgroup_e_css() use that instead? Thanks. -- tejun