Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1755836AbdGLJgt (ORCPT <rfc822;w@1wt.eu>);
        Wed, 12 Jul 2017 05:36:49 -0400
Received: from merlin.infradead.org ([205.233.59.134]:60072 "EHLO
        merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1750738AbdGLJgr (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 12 Jul 2017 05:36:47 -0400
Date: Wed, 12 Jul 2017 11:36:30 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Joel Fernandes <joelaf@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Patrick Bellasi <patrick.bellasi@arm.com>,
        Juri Lelli <juri.lelli@arm.com>,
        Andres Oportus <andresoportus@google.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Len Brown <lenb@kernel.org>, "Rafael J . Wysocki" <rjw@rjwysocki.net>,
        Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH RFC v4] cpufreq: schedutil: Make iowait boost more energy
 efficient
Message-ID: <20170712093630.lppm7yaqeiro2276@hirez.programming.kicks-ass.net>
References: <20170709170826.29396-1-joelaf@google.com>
 <20170711101432.GB17115@vireshk-i7>
 <CAJWu+oqgN+1V4AF2QowT+fT_5SMQoNMy7NgrO8Zf3eSvAByTCg@mail.gmail.com>
 <20170712050035.GH17115@vireshk-i7>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20170712050035.GH17115@vireshk-i7>
User-Agent: NeoMutt/20170609 (1.8.3)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 888
Lines: 21

On Wed, Jul 12, 2017 at 10:30:35AM +0530, Viresh Kumar wrote:
> On 11-07-17, 07:14, Joel Fernandes wrote:

> > Another approach than setting min in sugov_set_iowait_boost, is, since
> > we have already retrieved the current util, we can check if flags ==
> > SCHED_CPUFREQ_IOWAIT, then set initial the iowait_boost such that
> > (iowait_boost / iowait_boost_max) is aleast equal to (util / max) or
> > iowait_boost_min, which ever is lower.
> 
> So my concerns weren't only about the initial min value, but also that you
> reduce the freq from sugov_set_iowait_boost(). We can discuss what the ideal
> value to start with can be.

I'm not sure I see that. He only mucks with iowait_boost, not the actual
frequency afaict.

And sugov_iowait_boost() picks the highest of util vs iowait_boost,
which wasn't changed.

Or am I completely missing something? (that code is a bit hard to
follow)