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From:   Vincent Guittot <vincent.guittot@linaro.org>
Date:   Thu, 14 Dec 2023 12:06:23 +0100
Message-ID: <CAKfTPtApsWeEbbV03sx8vQTGc3i+oFsAWRNsLnyHjYCSrRMqhg@mail.gmail.com>
Subject: Re: [PATCH 1/4] cpufreq: Add a cpufreq pressure feedback for the scheduler
To:     Lukasz Luba <lukasz.luba@arm.com>
Cc:     catalin.marinas@arm.com, will@kernel.org,
        daniel.lezcano@linaro.org, mhiramat@kernel.org,
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On Thu, 14 Dec 2023 at 10:20, Lukasz Luba <lukasz.luba@arm.com> wrote:
>
>
>
> On 12/12/23 14:27, Vincent Guittot wrote:
> > Provide to the scheduler a feedback about the temporary max available
> > capacity. Unlike arch_update_thermal_pressure, this doesn't need to be
> > filtered as the pressure will happen for dozens ms or more.
> >
> > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
> > ---
> >   drivers/cpufreq/cpufreq.c | 48 +++++++++++++++++++++++++++++++++++++++
> >   include/linux/cpufreq.h   | 10 ++++++++
> >   2 files changed, 58 insertions(+)
> >
> > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> > index 44db4f59c4cc..7d5f71be8d29 100644
> > --- a/drivers/cpufreq/cpufreq.c
> > +++ b/drivers/cpufreq/cpufreq.c
> > @@ -2563,6 +2563,50 @@ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
> >   }
> >   EXPORT_SYMBOL(cpufreq_get_policy);
> >
> > +DEFINE_PER_CPU(unsigned long, cpufreq_pressure);
> > +EXPORT_PER_CPU_SYMBOL_GPL(cpufreq_pressure);
>
> Why do we export this variable when we have get/update functions?
> Do we expect modules would manipulate those per-cpu variables
> independently and not like we do per-cpumask in the update func.?

No, I will remove the EXPORT_PER_CPU_SYMBOL_GPL