All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: linux-arm-kernel@lists.infradead.org
Subject: Re: "cpufreq: fix serialization issues with freq change notifiers" breaks cpufreq too
Date: Tue, 10 Sep 2013 11:49:24 +0000	[thread overview]
Message-ID: <4292924.3iHJT5nzNS@vostro.rjw.lan> (raw)
In-Reply-To: <CAKohponZ+FnzqXYMbBzbun0-1iQMi2fS4syrEBC_MdF41vLCeA@mail.gmail.com>

On Tuesday, September 10, 2013 04:59:29 PM Viresh Kumar wrote:
> On 9 September 2013 20:41, Guennadi Liakhovetski <g.liakhovetski@gmx.de> wrote:
> > Sorry guys, I'm trying my best to stop this patch from propagating to
> > stable and to get it fixed asap, so, the CC list might be a bit excessive.
> > Also trying to fix the originally spare cc list, which makes it impossible
> > for me to reply to the original thread, instead have to start a new one.
> >
> > Commit
> >
> > commit dceff5ce18801dddc220d6238628619c93bc3cb6
> > Author: Viresh Kumar <viresh.kumar@linaro.org>
> > Date:   Sun Sep 1 22:19:37 2013 +0530
> >
> >     cpufreq: fix serialization issues with freq change notifiers
> >
> > breaks .transition_ongoing counting. This leads to cpufreq-cpu0 not
> > working any more. In particular switching the governor from performance to
> > powersave directly after boot doesn't result in a frequency switch any
> > more. Reverting this patch fixes the problem again. Tested with today's
> > -next.
> 
> I have tested it again on my exynos and intel machines and couldn't see
> a single problem with this patch..
> 
> I am afraid you need to give us some more information on how it broke
> your stuff.. :)
> 
> And I am also not sure cpufreq-cpu0 is different then any other driver..

That said I'm actually unsure what problems *exactly* are fixed by commit
7c30ed5.  The commit log only says that PRECHANGE or POSTCHAGE shouldn't be
called twice in a row, but it doesn't say why.  As the fallout indicates,
that actually happened before commit 7c30ed5 and nothing visibly broke, so
the benefit from having that commit is questionable to me.  On the other hand,
the commit itself is evidently broken, so what exactly is the reason for
keeping it?

Rafael


WARNING: multiple messages have this Message-ID (diff)
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>,
	Greg KH <greg@kroah.com>,
	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
	"cpufreq@vger.kernel.org" <cpufreq@vger.kernel.org>,
	SH-Linux <linux-sh@vger.kernel.org>,
	Magnus Damm <magnus.damm@gmail.com>
Subject: Re: "cpufreq: fix serialization issues with freq change notifiers" breaks cpufreq too
Date: Tue, 10 Sep 2013 13:49:24 +0200	[thread overview]
Message-ID: <4292924.3iHJT5nzNS@vostro.rjw.lan> (raw)
In-Reply-To: <CAKohponZ+FnzqXYMbBzbun0-1iQMi2fS4syrEBC_MdF41vLCeA@mail.gmail.com>

On Tuesday, September 10, 2013 04:59:29 PM Viresh Kumar wrote:
> On 9 September 2013 20:41, Guennadi Liakhovetski <g.liakhovetski@gmx.de> wrote:
> > Sorry guys, I'm trying my best to stop this patch from propagating to
> > stable and to get it fixed asap, so, the CC list might be a bit excessive.
> > Also trying to fix the originally spare cc list, which makes it impossible
> > for me to reply to the original thread, instead have to start a new one.
> >
> > Commit
> >
> > commit dceff5ce18801dddc220d6238628619c93bc3cb6
> > Author: Viresh Kumar <viresh.kumar@linaro.org>
> > Date:   Sun Sep 1 22:19:37 2013 +0530
> >
> >     cpufreq: fix serialization issues with freq change notifiers
> >
> > breaks .transition_ongoing counting. This leads to cpufreq-cpu0 not
> > working any more. In particular switching the governor from performance to
> > powersave directly after boot doesn't result in a frequency switch any
> > more. Reverting this patch fixes the problem again. Tested with today's
> > -next.
> 
> I have tested it again on my exynos and intel machines and couldn't see
> a single problem with this patch..
> 
> I am afraid you need to give us some more information on how it broke
> your stuff.. :)
> 
> And I am also not sure cpufreq-cpu0 is different then any other driver..

That said I'm actually unsure what problems *exactly* are fixed by commit
7c30ed5.  The commit log only says that PRECHANGE or POSTCHAGE shouldn't be
called twice in a row, but it doesn't say why.  As the fallout indicates,
that actually happened before commit 7c30ed5 and nothing visibly broke, so
the benefit from having that commit is questionable to me.  On the other hand,
the commit itself is evidently broken, so what exactly is the reason for
keeping it?

Rafael


WARNING: multiple messages have this Message-ID (diff)
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>,
	Greg KH <greg@kroah.com>,
	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
	"cpufreq@vger.kernel.org" <cpufreq@vger.kernel.org>,
	SH-Linux <linux-sh@vger.kernel.org>,
	Magnus Damm <magnus.damm@gmail.com>
Subject: Re: "cpufreq: fix serialization issues with freq change notifiers" breaks cpufreq too
Date: Tue, 10 Sep 2013 13:49:24 +0200	[thread overview]
Message-ID: <4292924.3iHJT5nzNS@vostro.rjw.lan> (raw)
In-Reply-To: <CAKohponZ+FnzqXYMbBzbun0-1iQMi2fS4syrEBC_MdF41vLCeA@mail.gmail.com>

On Tuesday, September 10, 2013 04:59:29 PM Viresh Kumar wrote:
> On 9 September 2013 20:41, Guennadi Liakhovetski <g.liakhovetski@gmx.de> wrote:
> > Sorry guys, I'm trying my best to stop this patch from propagating to
> > stable and to get it fixed asap, so, the CC list might be a bit excessive.
> > Also trying to fix the originally spare cc list, which makes it impossible
> > for me to reply to the original thread, instead have to start a new one.
> >
> > Commit
> >
> > commit dceff5ce18801dddc220d6238628619c93bc3cb6
> > Author: Viresh Kumar <viresh.kumar@linaro.org>
> > Date:   Sun Sep 1 22:19:37 2013 +0530
> >
> >     cpufreq: fix serialization issues with freq change notifiers
> >
> > breaks .transition_ongoing counting. This leads to cpufreq-cpu0 not
> > working any more. In particular switching the governor from performance to
> > powersave directly after boot doesn't result in a frequency switch any
> > more. Reverting this patch fixes the problem again. Tested with today's
> > -next.
> 
> I have tested it again on my exynos and intel machines and couldn't see
> a single problem with this patch..
> 
> I am afraid you need to give us some more information on how it broke
> your stuff.. :)
> 
> And I am also not sure cpufreq-cpu0 is different then any other driver..

That said I'm actually unsure what problems *exactly* are fixed by commit
7c30ed5.  The commit log only says that PRECHANGE or POSTCHAGE shouldn't be
called twice in a row, but it doesn't say why.  As the fallout indicates,
that actually happened before commit 7c30ed5 and nothing visibly broke, so
the benefit from having that commit is questionable to me.  On the other hand,
the commit itself is evidently broken, so what exactly is the reason for
keeping it?

Rafael


WARNING: multiple messages have this Message-ID (diff)
From: rjw@rjwysocki.net (Rafael J. Wysocki)
To: linux-arm-kernel@lists.infradead.org
Subject: "cpufreq: fix serialization issues with freq change notifiers" breaks cpufreq too
Date: Tue, 10 Sep 2013 13:49:24 +0200	[thread overview]
Message-ID: <4292924.3iHJT5nzNS@vostro.rjw.lan> (raw)
In-Reply-To: <CAKohponZ+FnzqXYMbBzbun0-1iQMi2fS4syrEBC_MdF41vLCeA@mail.gmail.com>

On Tuesday, September 10, 2013 04:59:29 PM Viresh Kumar wrote:
> On 9 September 2013 20:41, Guennadi Liakhovetski <g.liakhovetski@gmx.de> wrote:
> > Sorry guys, I'm trying my best to stop this patch from propagating to
> > stable and to get it fixed asap, so, the CC list might be a bit excessive.
> > Also trying to fix the originally spare cc list, which makes it impossible
> > for me to reply to the original thread, instead have to start a new one.
> >
> > Commit
> >
> > commit dceff5ce18801dddc220d6238628619c93bc3cb6
> > Author: Viresh Kumar <viresh.kumar@linaro.org>
> > Date:   Sun Sep 1 22:19:37 2013 +0530
> >
> >     cpufreq: fix serialization issues with freq change notifiers
> >
> > breaks .transition_ongoing counting. This leads to cpufreq-cpu0 not
> > working any more. In particular switching the governor from performance to
> > powersave directly after boot doesn't result in a frequency switch any
> > more. Reverting this patch fixes the problem again. Tested with today's
> > -next.
> 
> I have tested it again on my exynos and intel machines and couldn't see
> a single problem with this patch..
> 
> I am afraid you need to give us some more information on how it broke
> your stuff.. :)
> 
> And I am also not sure cpufreq-cpu0 is different then any other driver..

That said I'm actually unsure what problems *exactly* are fixed by commit
7c30ed5.  The commit log only says that PRECHANGE or POSTCHAGE shouldn't be
called twice in a row, but it doesn't say why.  As the fallout indicates,
that actually happened before commit 7c30ed5 and nothing visibly broke, so
the benefit from having that commit is questionable to me.  On the other hand,
the commit itself is evidently broken, so what exactly is the reason for
keeping it?

Rafael

  reply	other threads:[~2013-09-10 11:49 UTC|newest]

Thread overview: 103+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-09 15:11 "cpufreq: fix serialization issues with freq change notifiers" breaks cpufreq too Guennadi Liakhovetski
2013-09-09 15:11 ` Guennadi Liakhovetski
2013-09-09 15:11 ` Guennadi Liakhovetski
2013-09-09 15:11 ` Guennadi Liakhovetski
2013-09-09 20:57 ` Rafael J. Wysocki
2013-09-09 21:08   ` Rafael J. Wysocki
2013-09-09 21:08   ` Rafael J. Wysocki
2013-09-09 21:42   ` Guennadi Liakhovetski
2013-09-09 21:42     ` Guennadi Liakhovetski
2013-09-09 21:42     ` Guennadi Liakhovetski
2013-09-09 23:12     ` Rafael J. Wysocki
2013-09-09 23:12       ` Rafael J. Wysocki
2013-09-09 23:12       ` Rafael J. Wysocki
2013-09-10  1:46       ` Rafael J. Wysocki
2013-09-10  1:46         ` Rafael J. Wysocki
2013-09-10 11:29 ` Viresh Kumar
2013-09-10 11:41   ` Viresh Kumar
2013-09-10 11:29   ` Viresh Kumar
2013-09-10 11:29   ` Viresh Kumar
2013-09-10 11:49   ` Rafael J. Wysocki [this message]
2013-09-10 11:49     ` Rafael J. Wysocki
2013-09-10 11:49     ` Rafael J. Wysocki
2013-09-10 11:49     ` Rafael J. Wysocki
2013-09-10 15:14     ` Viresh Kumar
2013-09-10 15:26       ` Viresh Kumar
2013-09-10 15:14       ` Viresh Kumar
2013-09-10 15:14       ` Viresh Kumar
2013-09-10 19:46       ` Rafael J. Wysocki
2013-09-10 19:46         ` Rafael J. Wysocki
2013-09-10 19:46         ` Rafael J. Wysocki
2013-09-10 19:46         ` Rafael J. Wysocki
2013-09-11  8:38         ` Viresh Kumar
2013-09-11  8:50           ` Viresh Kumar
2013-09-11  8:38           ` Viresh Kumar
2013-09-11  8:38           ` Viresh Kumar
2013-09-11 13:18           ` Rafael J. Wysocki
2013-09-11 13:18             ` Rafael J. Wysocki
2013-09-11 13:18             ` Rafael J. Wysocki
2013-09-11 13:18             ` Rafael J. Wysocki
2013-09-12  0:39             ` Viresh Kumar
2013-09-12  0:51               ` Viresh Kumar
2013-09-12  0:39               ` Viresh Kumar
2013-09-12  0:39               ` Viresh Kumar
2013-09-12  0:43               ` Rafael J. Wysocki
2013-09-12  0:43                 ` Rafael J. Wysocki
2013-09-12  0:43                 ` Rafael J. Wysocki
2013-09-12  0:43                 ` Rafael J. Wysocki
2013-09-12  5:36                 ` Viresh Kumar
2013-09-12  5:48                   ` Viresh Kumar
2013-09-12  5:36                   ` Viresh Kumar
2013-09-12  5:36                   ` Viresh Kumar
2013-09-12 10:50                   ` Rafael J. Wysocki
2013-09-12 11:01                     ` Rafael J. Wysocki
2013-09-12 11:01                     ` Rafael J. Wysocki
2013-09-12 11:01                     ` Rafael J. Wysocki
2013-09-12 10:52                     ` Viresh Kumar
2013-09-12 10:52                       ` Viresh Kumar
2013-09-12 10:52                       ` Viresh Kumar
2013-09-12 10:52                       ` Viresh Kumar
2013-09-10 15:12   ` Guennadi Liakhovetski
2013-09-10 15:12     ` Guennadi Liakhovetski
2013-09-10 15:12     ` Guennadi Liakhovetski
2013-09-10 15:12     ` Guennadi Liakhovetski
2013-09-10 15:26     ` Viresh Kumar
2013-09-10 15:38       ` Viresh Kumar
2013-09-10 15:26       ` Viresh Kumar
2013-09-10 15:26       ` Viresh Kumar
2013-09-10 16:22       ` Guennadi Liakhovetski
2013-09-10 16:22         ` Guennadi Liakhovetski
2013-09-10 16:22         ` Guennadi Liakhovetski
2013-09-10 16:22         ` Guennadi Liakhovetski
2013-09-10 16:34         ` Viresh Kumar
2013-09-10 16:46           ` Viresh Kumar
2013-09-10 16:34           ` Viresh Kumar
2013-09-10 16:34           ` Viresh Kumar
2013-09-10 17:07           ` Guennadi Liakhovetski
2013-09-10 17:07             ` Guennadi Liakhovetski
2013-09-10 17:07             ` Guennadi Liakhovetski
2013-09-10 17:07             ` Guennadi Liakhovetski
2013-09-11  8:06             ` Viresh Kumar
2013-09-11  8:18               ` Viresh Kumar
2013-09-11  8:06               ` Viresh Kumar
2013-09-11  8:06               ` Viresh Kumar
2013-09-11  8:15               ` Guennadi Liakhovetski
2013-09-11  8:15                 ` Guennadi Liakhovetski
2013-09-11  8:15                 ` Guennadi Liakhovetski
2013-09-11  8:15                 ` Guennadi Liakhovetski
2013-09-11  8:39                 ` Viresh Kumar
2013-09-11  8:51                   ` Viresh Kumar
2013-09-11  8:39                   ` Viresh Kumar
2013-09-11  8:39                   ` Viresh Kumar
2013-09-11 13:28                 ` Rafael J. Wysocki
2013-09-11 13:28                   ` Rafael J. Wysocki
2013-09-11 13:28                   ` Rafael J. Wysocki
2013-09-11 13:28                   ` Rafael J. Wysocki
2013-09-12  7:47               ` Guennadi Liakhovetski
2013-09-12  7:47                 ` Guennadi Liakhovetski
2013-09-12  7:47                 ` Guennadi Liakhovetski
2013-09-12  7:47                 ` Guennadi Liakhovetski
2013-09-12  7:51                 ` Viresh Kumar
2013-09-12  7:51                   ` Viresh Kumar
2013-09-12  7:51                   ` Viresh Kumar
2013-09-12  7:51                   ` Viresh Kumar

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=4292924.3iHJT5nzNS@vostro.rjw.lan \
    --to=rjw@rjwysocki.net \
    --cc=linux-arm-kernel@lists.infradead.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.