public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Patrick Bellasi <patrick.bellasi@arm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Linux PM <linux-pm@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Juri Lelli <juri.lelli@arm.com>,
	Joel Fernandes <joelaf@google.com>,
	Morten Rasmussen <morten.rasmussen@arm.com>,
	Ingo Molnar <mingo@redhat.com>
Subject: Re: [RFC][PATCH v2 2/2] cpufreq: schedutil: Avoid decreasing frequency of busy CPUs
Date: Tue, 21 Mar 2017 19:28:19 +0000	[thread overview]
Message-ID: <20170321192819.GG11054@e110439-lin> (raw)
In-Reply-To: <20170321151827.GW3093@worktop>

On 21-Mar 16:18, Peter Zijlstra wrote:
> On Tue, Mar 21, 2017 at 03:08:20PM +0000, Patrick Bellasi wrote:
> 
> > And than we can move this bit into an inline function, something like e.g.:
> > 
> >    static inline bool sugov_this_cpu_is_busy()
> >    {
> >            return this_rq()->rd->overloaded
> >    }
> 
> No, that's just entirely and utterly wrong. It being in rd means its
> very much not about _this_ CPU in any way.

You right (of course), we cannot really use "this_" in the name of
a function with such a code.

The suggestion here was at least to factor out whatever code we want
to use to check if the current CPU has to be subject to a down-scaling
constraint.

However, using rd->overload is not the best option, for the many reasons
you explained in your previous comment. Thus, we should probably stay
with the idle time tracking solution initially proposed by Rafael.

Sorry for the noise :-(

-- 
#include <best/regards.h>

Patrick Bellasi

  reply	other threads:[~2017-03-21 19:28 UTC|newest]

Thread overview: 71+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-19 13:21 [PATCH 0/2] cpufreq: schedutil: Fix and optimization Rafael J. Wysocki
2017-03-19 13:30 ` [PATCH 1/2] cpufreq: schedutil: Fix per-CPU structure initialization in sugov_start() Rafael J. Wysocki
2017-03-20  3:28   ` Viresh Kumar
2017-03-20 12:36     ` Rafael J. Wysocki
2017-03-19 13:34 ` [RFC][PATCH 2/2] cpufreq: schedutil: Force max frequency on busy CPUs Rafael J. Wysocki
2017-03-19 21:24   ` Rafael J. Wysocki
2017-03-19 21:42     ` Rafael J. Wysocki
2017-03-20 10:38     ` Peter Zijlstra
2017-03-20 12:31       ` Rafael J. Wysocki
2017-03-20  3:57   ` Viresh Kumar
2017-03-20  8:26     ` Vincent Guittot
2017-03-20 12:34       ` Patrick Bellasi
2017-03-22 23:56         ` Joel Fernandes
2017-03-23 22:08           ` Vincent Guittot
2017-03-25  3:48             ` Joel Fernandes
2017-03-27  6:59               ` Vincent Guittot
2017-03-20 12:59       ` Rafael J. Wysocki
2017-03-20 13:20         ` Vincent Guittot
2017-03-20 12:48     ` Rafael J. Wysocki
2017-03-20 10:36   ` Peter Zijlstra
2017-03-20 12:35     ` Rafael J. Wysocki
2017-03-20 12:50       ` Peter Zijlstra
2017-03-20 13:04         ` Rafael J. Wysocki
2017-03-20 13:06         ` Patrick Bellasi
2017-03-20 13:05           ` Rafael J. Wysocki
2017-03-20 14:13             ` Patrick Bellasi
2017-03-20 21:46   ` [RFC][PATCH v2 2/2] cpufreq: schedutil: Avoid decreasing frequency of " Rafael J. Wysocki
2017-03-21  6:40     ` Viresh Kumar
2017-03-21 12:30       ` Rafael J. Wysocki
2017-03-21  8:50     ` Vincent Guittot
2017-03-21 11:56       ` Patrick Bellasi
2017-03-21 13:22       ` Peter Zijlstra
2017-03-21 13:37         ` Vincent Guittot
2017-03-21 14:03           ` Peter Zijlstra
2017-03-21 14:18             ` Vincent Guittot
2017-03-21 14:25             ` Patrick Bellasi
     [not found]             ` <CAKfTPtALorn7HNpz4LOfWWSc3u+9y5iHB5byzfTHGQXDA+tVJQ@mail.gmail.com>
2017-03-21 14:58               ` Peter Zijlstra
2017-03-21 17:00                 ` Vincent Guittot
2017-03-21 17:01                   ` Vincent Guittot
2017-03-21 14:26           ` Rafael J. Wysocki
2017-03-21 14:38             ` Patrick Bellasi
2017-03-21 14:46               ` Rafael J. Wysocki
2017-03-21 14:50                 ` Rafael J. Wysocki
2017-03-21 15:04                 ` Peter Zijlstra
2017-03-21 15:18                   ` Rafael J. Wysocki
2017-03-21 17:00                     ` Peter Zijlstra
2017-03-21 17:17                       ` Rafael J. Wysocki
2017-03-21 15:08                 ` Patrick Bellasi
2017-03-21 15:18                   ` Peter Zijlstra
2017-03-21 19:28                     ` Patrick Bellasi [this message]
2017-03-21 15:02             ` Peter Zijlstra
2017-03-21 11:50     ` Patrick Bellasi
2017-03-21 23:08     ` [RFC][PATCH v3 2/2] cpufreq: schedutil: Avoid reducing frequency of busy CPUs prematurely Rafael J. Wysocki
2017-03-22  9:26       ` Peter Zijlstra
2017-03-22  9:54       ` Viresh Kumar
2017-03-23  1:04       ` Joel Fernandes
2017-03-23 19:26       ` Sai Gurrappadi
2017-03-23 20:48         ` Sai Gurrappadi
2017-03-24  1:39         ` Rafael J. Wysocki
2017-03-24 19:08           ` Sai Gurrappadi
2017-03-25  1:14       ` Sai Gurrappadi
2017-03-25  1:39         ` Rafael J. Wysocki
2017-03-27  7:04         ` Vincent Guittot
2017-03-27 21:01           ` Sai Gurrappadi
2017-03-27 21:11             ` Rafael J. Wysocki
2017-05-08  3:49       ` Wanpeng Li
2017-05-08  4:01         ` Viresh Kumar
2017-05-08  5:15           ` Wanpeng Li
2017-05-08 22:16           ` Rafael J. Wysocki
2017-05-08 22:36             ` Wanpeng Li
2017-05-08 23:01               ` Rafael J. Wysocki

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170321192819.GG11054@e110439-lin \
    --to=patrick.bellasi@arm.com \
    --cc=joelaf@google.com \
    --cc=juri.lelli@arm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=morten.rasmussen@arm.com \
    --cc=peterz@infradead.org \
    --cc=rjw@rjwysocki.net \
    --cc=srinivas.pandruvada@linux.intel.com \
    --cc=vincent.guittot@linaro.org \
    --cc=viresh.kumar@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox