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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH, USER_AGENT_MUTT autolearn=ham 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 59E95C28CC5 for ; Wed, 5 Jun 2019 14:09:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 31275206C3 for ; Wed, 5 Jun 2019 14:09:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559743788; bh=yKxA3rdyxLJHjaMDN8/8gJKUPfST4txhCcUpAmxJDDk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=mSfUeQJo3qJeTRmdUL7EuQB+WtNLw2VDHaN7jiRR0ceLkGWueJkdNKGJKGKS4vhIH 6RQvaUU3hhya4x5m9R6kgUSzgwpduZLLYyDhuHHruXiv0gG/ewPph4e3j+oOLAzBMS IdxMGT+lTVsAB5BEGQICAxLdrB5Y2sKiYnNwaGOg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728328AbfFEOJr (ORCPT ); Wed, 5 Jun 2019 10:09:47 -0400 Received: from mail-qt1-f196.google.com ([209.85.160.196]:42566 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726442AbfFEOJr (ORCPT ); Wed, 5 Jun 2019 10:09:47 -0400 Received: by mail-qt1-f196.google.com with SMTP id s15so18055070qtk.9; Wed, 05 Jun 2019 07:09:46 -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:in-reply-to:user-agent; bh=v2MDSX43JHH0KYjwpIjVIi4kIeO7/cbyv9lPzZyoCrE=; b=OVxjPMU8vSgMBWq01KiF8vrtW3d0wVXT2TRlMY7sfjlbCyidt/5GhQIrM9QaBbhXK8 yBBwNSjvNWUGNy4aaGMYIscuEKbhFOGhorRKCaOUadE8F9K+Of8SlEKCVZg/KO1AKcYZ pLPhZTy74Pp0mgiNyxkil96aHglcrJc55A9kqhfsBvTdbMQicRUtIMxj9hr9Ak9mHXnR tiG08FPK+JMidIbMnzDzsl6O7SEkqTX6bdUvGjwXdZIbxnFPnXRb7M5s0M0bzfi/NbiR 2k+FWmDk0/4S1ptJ/zsgSvGr3S6p5nPv0UCDziiS9ndZTLXlodNZ377uPGrp/Ax6rZd/ O1Hg== 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:in-reply-to:user-agent; bh=v2MDSX43JHH0KYjwpIjVIi4kIeO7/cbyv9lPzZyoCrE=; b=EVNu17Neay7DNF2aLQM5Am2NV9N2wtZW0EtGXJL9KR5GdhEQzx6CD7LbwvTzulG/1O A69c6jIzdRu20y59Fd8WfPDsrgtZY51GVYX1LgYrHty1sBLJ1LaqvX0ziIjs37z3FVHP ol9wiYzHvsoqCvjuiGUTaS95xfJJjGJxQ+xbdWOA3JxeJyDst38PHYgKbuShRW/YUdyj qJjwK/azgOqyZ23/5Cb5+DbTIXJ6//5ozg+ECVKATE2vc0BnisMvruYxHU1nF2kxbnK2 84kyJS39glXXbGS+/Rta8U3lVVSna9TYbWLDhEe7WELO5MLIIOoLGgfwmQRaz4stlApe PEgQ== X-Gm-Message-State: APjAAAUDra4OFNuJxbofADSPl8Od4crKEiXS+0q1LJpUz6y8T4sGZ07I YLn9t7HsIZztAHx6vDIuQNk= X-Google-Smtp-Source: APXvYqyznVqtqIoUN6wPQaRIrn1PSPcfNmqktReX7Bd4iJaFk86Dqnry9/4HbTgpLOJFuFZf4qUokQ== X-Received: by 2002:a0c:baa7:: with SMTP id x39mr14333646qvf.100.1559743785693; Wed, 05 Jun 2019 07:09:45 -0700 (PDT) Received: from localhost ([2620:10d:c091:500::1:c027]) by smtp.gmail.com with ESMTPSA id d5sm9336669qtj.3.2019.06.05.07.09.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 05 Jun 2019 07:09:44 -0700 (PDT) Date: Wed, 5 Jun 2019 07:09:43 -0700 From: Tejun Heo To: Patrick Bellasi Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-api@vger.kernel.org, Ingo Molnar , "Rafael J . Wysocki" , Vincent Guittot , Viresh Kumar , Paul Turner , Quentin Perret , Dietmar Eggemann , Morten Rasmussen , Juri Lelli , Todd Kjos , Joel Fernandes , Steve Muckle , Suren Baghdasaryan Subject: Re: [PATCH v9 12/16] sched/core: uclamp: Extend CPU's cgroup controller Message-ID: <20190605140943.GM374014@devbig004.ftw2.facebook.com> References: <20190515094459.10317-1-patrick.bellasi@arm.com> <20190515094459.10317-13-patrick.bellasi@arm.com> <20190531153545.GE374014@devbig004.ftw2.facebook.com> <20190603122929.GC19426@darkstar> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190603122929.GC19426@darkstar> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Mon, Jun 03, 2019 at 01:29:29PM +0100, Patrick Bellasi wrote: > On 31-May 08:35, Tejun Heo wrote: > > Hello, Patrick. > > > > On Wed, May 15, 2019 at 10:44:55AM +0100, Patrick Bellasi wrote: > > [...] > > > For proportions (as opposed to weights), we use percentage rational > > numbers - e.g. 38.44 for 38.44%. I have parser and doc update commits > > pending. I'll put them on cgroup/for-5.3. > > That's a point worth discussing with Peter, we already changed one > time from percentages to 1024 scale. cgroup tries to uss uniform units for its interface files as much as possible even when that deviates from non-cgroup interface. We can bikeshed the pros and cons for that design choice for sure but I don't think it makes sense to deviate from that at this point unless there are really strong reasons to do so. > Utilization clamps are expressed as percentages by definition, > they are just expressed in a convenient 1024 scale which should not be > alien to people using those knobs. > > If we wanna use a "more specific" name like uclamp.{min,max} then we > should probably also accept to use a "more specific" metric, don't we? Heh, this actually made me chuckle. It's an interesting bargaining take but I don't think that same word being in two different places makes them tradable entities. We can go into the weeds with the semantics but how about us using an alternative adjective "misleading" for the cpu.util.min/max names to short-circuit that? Thanks. -- tejun