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 X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A598C49ED8 for ; Tue, 10 Sep 2019 16:09:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 445D3206A1 for ; Tue, 10 Sep 2019 16:09:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568131740; bh=Iyom6nVo13zvWT0J4vP9mpQMZj8t1KHSkeSG+h6adVs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=W6iWsx0DW/wymKMIbfLqm7epIoIRUPWj3z9wkpFM96sOUheKw+B0v2bGGpfFsP0pU 9iTWvRkAzWMT2kX9WMRwPGMv6hmowhhokfi4XgUSdHMoCnIbLW7hcGxhDcr9p+1R91 pxXsVXTClFcSpBrWPElWRq5R+2EUkpqUTDXPayIA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394077AbfIJQI7 (ORCPT ); Tue, 10 Sep 2019 12:08:59 -0400 Received: from mail-qt1-f194.google.com ([209.85.160.194]:36605 "EHLO mail-qt1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726998AbfIJQI7 (ORCPT ); Tue, 10 Sep 2019 12:08:59 -0400 Received: by mail-qt1-f194.google.com with SMTP id o12so21425827qtf.3; Tue, 10 Sep 2019 09:08:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=bdd/RVi8vfAfg851AYquHh04me7NuiJ7iVVTsDpYp68=; b=fUA+fYqvDaEh6XnC8UBQ3JpjN/2WjcxI+8CiRk4SalHIoVe5prkjFMu71bb/uLhLEi vdSRmM1ImkGHh+5l222crJZZ8/ZbN5H9jaqs5XiMxOkLTzGZGkekXnXHoceWM87OVVZW t0OZsTU5TT8dmyCn/uOnVU4OzwLHubfn9Uk/eyxwR46e9wcUNF0twyojDJIJ4r9hPgm+ ctrVk79+ExOfFiWG/zP/jiTtOv9aL/Mk6GmHBR0tH9tBI793M0JSgUKIbdE11v4CZcki biWouuq8snH+yIDMNXZDgpkw+bvxzlXrTIXXskJqm/qPfuoXfRt7hgJ7cl/2r4M4jd6M /rRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=bdd/RVi8vfAfg851AYquHh04me7NuiJ7iVVTsDpYp68=; b=Xt5SG5XtyBA6qhASIRM4KZGFpyopS97sn8S5HuVAFUEbkVzbcEsEyDWUHo1RX1mwrW rhQG9GLGfmIGNhOP3G+V5XbJP0/LyKEPvCQXmy6uJkYVuRXzT9CigmeimNN72DXwbTlS zpFWATZi5N9rrPzyUxPOR4+X9zHvLO0oQE4MXq/nxiZLb5s/kzDlssfqRjSzCHsbz6D9 fFD/rvzTbF6NRtUD2IyWDax53rPajgUWVWQmduRvPFvX8g1jNpuSzdDDgkkQcTrJkk99 bfSzed4xzb7DZHoFqIFLYsdDxMNv4CT+5a+mb6sElaCpTrQyExoWfm020ri3ZH1k9Bxb 8c+Q== X-Gm-Message-State: APjAAAWPIbZUEyyqpRYG70FV9tEbe6mC9V0sAO03Z5vWqerhrI8gsDlX EmghMwuQtq2teD9SWSg+pPY= X-Google-Smtp-Source: APXvYqy1mXMLatf/bfCumeTCUJ4Qv5l0eyL7tNeUKutGwTA1BrLjrBcgiAJOawTlqrJzUwRaNUHvnw== X-Received: by 2002:ac8:23b9:: with SMTP id q54mr31058151qtq.107.1568131737923; Tue, 10 Sep 2019 09:08:57 -0700 (PDT) Received: from localhost ([2620:10d:c091:500::2:f049]) by smtp.gmail.com with ESMTPSA id a134sm9730633qkc.95.2019.09.10.09.08.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 10 Sep 2019 09:08:57 -0700 (PDT) Date: Tue, 10 Sep 2019 09:08:55 -0700 From: Tejun Heo To: Michal =?iso-8859-1?Q?Koutn=FD?= Cc: hannes@cmpxchg.org, clm@fb.com, dennisz@fb.com, newella@fb.com, lizefan@huawei.com, axboe@kernel.dk, josef@toxicpanda.com, Josef Bacik , kernel-team@fb.com, Rik van Riel , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Paolo Valente Subject: Re: [PATCH 08/10] blkcg: implement blk-iocost Message-ID: <20190910160855.GS2263813@devbig004.ftw2.facebook.com> References: <20190828220600.2527417-1-tj@kernel.org> <20190828220600.2527417-9-tj@kernel.org> <20190910125513.GA6399@blackbody.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190910125513.GA6399@blackbody.suse.cz> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hello, Michal. On Tue, Sep 10, 2019 at 02:55:14PM +0200, Michal Koutný wrote: > This adds the generic io.weight attribute. How will this compose with > the weight from IO schedulers? (AFAIK, only BFQ allows proportional > control as of now. +CC Paolo.) The two being enabled at the same time doesn't make sense, so we can just switch over to bfq when bfq is selected as the iosched. I asked what Paolo wanted to do in terms of interface a couple times now but didn't get an answer and he posted a patch which makes the two controllers conflict, so.... Paolo, so it looks like you want to rename all bfq files to drop the bfq prefix, right? I can implement the switching if so. > I see this attributes are effectively per-cgroup per-device. Apparently, > one device should have only one weight across hierarchy. Would it make > sense to have io.bfq.weight and io.cost.weight with disjunctive devices? It never makes sense to have both enabled, so I don't think that interface makes sense. > > + .name = "cost.qos", > > + .flags = CFTYPE_ONLY_ON_ROOT, > > [...] > > + .name = "cost.model", > > + .flags = CFTYPE_ONLY_ON_ROOT, > I'm concerned that these aren't true cgroup attributes. The root cgroup > would act as container for global configuration options. Wouldn't these > values better fit as (configurable) attributes of the respective > devices? Initially, I put them under block device sysfs but it was too clumsy with different config file formats and all. I think it's better to have global controller configs at the root cgroup. > Secondly, how is CFTYPE_ONLY_ON_ROOT supposed to be presented in cgroup > namespaces? Not at all. These are system-wide configs. cgroup namespaces shouldn't have anything which aren't in non-root cgroups. Thanks. -- tejun