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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 0B94EC54FC9 for ; Tue, 21 Apr 2020 11:16:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E93A4205C9 for ; Tue, 21 Apr 2020 11:16:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728602AbgDULQU (ORCPT ); Tue, 21 Apr 2020 07:16:20 -0400 Received: from foss.arm.com ([217.140.110.172]:33334 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726018AbgDULQT (ORCPT ); Tue, 21 Apr 2020 07:16:19 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B041AC14; Tue, 21 Apr 2020 04:16:18 -0700 (PDT) Received: from [192.168.0.7] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B19C93F73D; Tue, 21 Apr 2020 04:16:15 -0700 (PDT) Subject: Re: [PATCH 1/2] sched/uclamp: Add a new sysctl to control RT default boost value To: Steven Rostedt , Qais Yousef Cc: Patrick Bellasi , Ingo Molnar , Peter Zijlstra , Jonathan Corbet , Juri Lelli , Vincent Guittot , Ben Segall , Mel Gorman , Luis Chamberlain , Kees Cook , Iurii Zaikin , Quentin Perret , Valentin Schneider , Pavan Kondeti , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org References: <20200403123020.13897-1-qais.yousef@arm.com> <20200414182152.GB20442@darkstar> <54ac2709-54e5-7a33-a6af-0a07e272365c@arm.com> <20200420151941.47ualxul5seqwdgh@e107158-lin.cambridge.arm.com> <20200420205210.7217651c@oasis.local.home> From: Dietmar Eggemann Message-ID: <1abbe4a5-61e6-a918-ff89-3dea0c7a277c@arm.com> Date: Tue, 21 Apr 2020 13:16:03 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20200420205210.7217651c@oasis.local.home> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 21/04/2020 02:52, Steven Rostedt wrote: > On Mon, 20 Apr 2020 16:19:42 +0100 > Qais Yousef wrote: > >>> root@h960:~# find / -name "*util_clamp*" >>> /proc/sys/kernel/sched_rt_default_util_clamp_min >>> /proc/sys/kernel/sched_util_clamp_max >>> /proc/sys/kernel/sched_util_clamp_min >>> >>> IMHO, keeping the common 'sched_util_clamp_' would be helpful here, e.g. >>> >>> /proc/sys/kernel/sched_util_clamp_rt_default_min >> >> All RT related knobs are prefixed with 'sched_rt'. I kept the 'util_clamp_min' >> coherent with the current sysctl (sched_util_clamp_min). Quentin suggested >> adding 'default' to be more obvious, so I ended up with >> >> 'sched_rt' + '_default' + '_util_clamp_min'. >> >> I think this is the logical and most consistent form. Given that Patrick seems >> to be okay with the 'default' now, does this look good to you too? > > There's only two files with "sched_rt" and they are tightly coupled > (they define how much an RT task may use the CPU). > > My question is, is this "sched_rt_default_util_clamp_min" related in > any way to those other two files that start with "sched_rt", or is it > more related to the files that start with "sched_util_clamp"? > > If the latter, then I would suggest using > "sched_util_clamp_min_rt_default", as it looks to be more related to > the "sched_util_clamp_min" than to anything else. For me it's the latter.