Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers

From	Viresh Kumar <viresh.kumar@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers
Date	2015-12-08 14:40 +0100
Message-ID	<qDqEO-2Xv-15@gated-at.bofh.it> (permalink)
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On 08-12-15, 14:18, Rafael J. Wysocki wrote:
> Well, if the timer function runs on all CPUs at the same time, they all
> can see skip_work > 1 and none of them will queue the work.

You are talking about code after my patch, right?

Will will all of them see it > 1? At least one of them will see it 0
and queue the work, unless the governor is stopped completely.

> You are right, I've overlooked that race (but then it is rather easy to
> overlook).

Yeah, we (at least I) took a long time to understand that this was the
real problem we always had and so fixed it recently.

-- 
viresh
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Thread

[PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-03 05:10 +0100
  Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-04 01:50 +0100
    Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-04 07:20 +0100
      Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-05 02:50 +0100
        Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-05 05:20 +0100
          Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-07 02:00 +0100
            Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-07 09:00 +0100
              Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-07 23:20 +0100
                Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-07 23:50 +0100
                [PATCH][experimantal] cpufreq: governor: Use an atomic variable for synchronization "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-08 01:20 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable  for synchronization Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 08:00 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable for synchronization "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-08 14:10 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable  for synchronization Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 14:40 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable for synchronization "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-08 14:50 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable  for synchronization Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 15:00 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable for synchronization "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-08 15:10 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable  for synchronization Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 16:00 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable for synchronization "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-08 17:20 +0100
                Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable  for synchronization Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 17:40 +0100
                Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 07:50 +0100
                Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 08:00 +0100
                Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-08 13:50 +0100
                Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-08 14:40 +0100
                Re: [PATCH V2 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-08 14:40 +0100
  [PATCH V3 5/6] cpufreq: governor: replace per-cpu delayed work with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-04 07:20 +0100
    [PATCH V4 5/6] cpufreq: governor: replace per-cpu delayed work with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-09 03:10 +0100
      Re: [PATCH V4 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-09 22:40 +0100
        Re: [PATCH V4 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-10 03:40 +0100
          Re: [PATCH V4 5/6] cpufreq: governor: replace per-cpu delayed work with timers "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-12-10 22:50 +0100
            Re: [PATCH V4 5/6] cpufreq: governor: replace per-cpu delayed work  with timers Viresh Kumar <viresh.kumar@linaro.org> - 2015-12-11 02:50 +0100

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