RE: [PATCH 10/12] cpufreq: cpufreq: export cpufreq cpu release and acquire

[Yuan, Perry]

[AMD Official Use Only - General]

Hi Nathon. 

> -----Original Message-----
> From: Fontenot, Nathan <Nathan.Fontenot@xxxxxxx>
> Sent: Friday, July 8, 2022 3:40 AM
> To: Yuan, Perry <Perry.Yuan@xxxxxxx>; rafael.j.wysocki@xxxxxxxxx;
> viresh.kumar@xxxxxxxxxx; Huang, Ray <Ray.Huang@xxxxxxx>; Rafael J.
> Wysocki <rafael@xxxxxxxxxx>; linux-pm@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Cc: Sharma, Deepak <Deepak.Sharma@xxxxxxx>; Limonciello, Mario
> <Mario.Limonciello@xxxxxxx>; Fontenot, Nathan
> <Nathan.Fontenot@xxxxxxx>; Deucher, Alexander
> <Alexander.Deucher@xxxxxxx>; Su, Jinzhou (Joe) <Jinzhou.Su@xxxxxxx>;
> Huang, Shimmer <Shimmer.Huang@xxxxxxx>; Du, Xiaojian
> <Xiaojian.Du@xxxxxxx>; Meng, Li (Jassmine) <Li.Meng@xxxxxxx>
> Subject: Re: [PATCH 10/12] cpufreq: cpufreq: export cpufreq cpu release and
> acquire
> 
> On 7/7/22 12:01, Perry Yuan wrote:
> > cpufreq_cpu_release" and "cpufreq_cpu_acquire" are only used
> > internally by drivers/cpufreq/cpufreq.c currently.
> > Export them so that other drivers such as the AMD P-state driver can use
> them as well.
> >
> 
> Can you provide more information on why this is needed for the amd-
> pstate driver?
> 
> This patch exports the acquire/release functions but I don't see that the
> amd-pstate driver is updated to use them.
> 
> -Nathan

It is used in the next CPPC EPP patch set which will be sent out soon.
As the amd-pstate is built as module driver, this patch exports the symbol to pstate driver. 

Perry.

> 
> > Signed-off-by: Perry Yuan <Perry.Yuan@xxxxxxx>
> > ---
> >  drivers/cpufreq/cpufreq.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> > index 73432360e6e9..4d3c83da29b7 100644
> > --- a/drivers/cpufreq/cpufreq.c
> > +++ b/drivers/cpufreq/cpufreq.c
> > @@ -262,6 +262,7 @@ void cpufreq_cpu_release(struct cpufreq_policy
> > *policy)
> >
> >  	cpufreq_cpu_put(policy);
> >  }
> > +EXPORT_SYMBOL_GPL(cpufreq_cpu_release);
> >
> >  /**
> >   * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it.
> > @@ -291,6 +292,7 @@ struct cpufreq_policy
> > *cpufreq_cpu_acquire(unsigned int cpu)
> >
> >  	return policy;
> >  }
> > +EXPORT_SYMBOL_GPL(cpufreq_cpu_acquire);
> >
> >
> /**************************************************************
> *******
> >   *            EXTERNALLY AFFECTING FREQUENCY CHANGES                 *