Re: [PATCH V2 1/2] cpufreq: ondemand: allow custom powersave_bias_target function to be registered

Jacob Shin
2013-04-02T14:36:28Z

On Tue, Apr 02, 2013 at 02:43:32PM +0200, Borislav Petkov wrote:
> On Thu, Mar 28, 2013 at 01:24:16PM -0500, Jacob Shin wrote:
> > This allows for another [arch specific] driver to hook into existing
> > powersave bias function of the ondemand governor. i.e. This allows AMD
> > specific powersave bias function (in a separate AMD specific driver)
> > to aid ondemand governor's frequency transition deicisions.
> >
> > Signed-off-by: Jacob Shin <jacob.shin@amd.com>
> > ---
> > drivers/cpufreq/cpufreq_governor.h | 3 +++
> > drivers/cpufreq/cpufreq_ondemand.c | 22 +++++++++++++++++++---
> > 2 files changed, 22 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
> > index c83cabf..4b6808f 100644
> > --- a/drivers/cpufreq/cpufreq_governor.h
> > +++ b/drivers/cpufreq/cpufreq_governor.h
> > @@ -262,4 +262,7 @@ bool need_load_eval(struct cpu_dbs_common_info *cdbs,
> > unsigned int sampling_rate);
> > int cpufreq_governor_dbs(struct cpufreq_policy *policy,
> > struct common_dbs_data *cdata, unsigned int event);
> > +void od_register_powersave_bias_function(unsigned int (*f)
> > + (struct cpufreq_policy *, unsigned int, unsigned int));
> > +void od_unregister_powersave_bias_function(void);
>
> We generally call those a "callback" or a "handler". I.e.,
> od_register_powersave_bias_handler or something.

Okay, will change.

>
> > #endif /* _CPUFREQ_GOVERNER_H */
> > diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
> > index 15e80ee..36f0798 100644
> > --- a/drivers/cpufreq/cpufreq_ondemand.c
> > +++ b/drivers/cpufreq/cpufreq_ondemand.c
> > @@ -40,6 +40,8 @@
> >
> > static DEFINE_PER_CPU(struct od_cpu_dbs_info_s, od_cpu_dbs_info);
> >
> > +static struct od_ops od_ops;
> > +
> > #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND
> > static struct cpufreq_governor cpufreq_gov_ondemand;
> > #endif
> > @@ -145,7 +147,8 @@ static void dbs_freq_increase(struct cpufreq_policy *p, unsigned int freq)
> > struct od_dbs_tuners *od_tuners = dbs_data->tuners;
> >
> > if (od_tuners->powersave_bias)
> > - freq = powersave_bias_target(p, freq, CPUFREQ_RELATION_H);
> > + freq = od_ops.powersave_bias_target(p, freq,
> > + CPUFREQ_RELATION_H);
> > else if (p->cur == p->max)
> > return;
> >
> > @@ -206,8 +209,8 @@ static void od_check_cpu(int cpu, unsigned int load_freq)
> > __cpufreq_driver_target(policy, freq_next,
> > CPUFREQ_RELATION_L);
> > } else {
> > - int freq = powersave_bias_target(policy, freq_next,
> > - CPUFREQ_RELATION_L);
> > + int freq = od_ops.powersave_bias_target(policy,
> > + freq_next, CPUFREQ_RELATION_L);
> > __cpufreq_driver_target(policy, freq,
> > CPUFREQ_RELATION_L);
> > }
> > @@ -565,6 +568,19 @@ static struct common_dbs_data od_dbs_cdata = {
> > .exit = od_exit,
> > };
> >
> > +void od_register_powersave_bias_function(unsigned int (*f)
> > + (struct cpufreq_policy *, unsigned int, unsigned int))
> > +{
> > + od_ops.powersave_bias_target = f;
> > +}
> > +EXPORT_SYMBOL_GPL(od_register_powersave_bias_function);
> > +
> > +void od_unregister_powersave_bias_function(void)
> > +{
> > + od_ops.powersave_bias_target = powersave_bias_target;
>
> This is very confusing: we have ->powersave_bias_target and the default
> powersave_bias_target in the ondemand governor. Can we call the default
> one generic_powersave_bias_target or default_* or whatever.

Okay, will do.

Thanks!

>
> Thanks.
>
> --
> Regards/Gruss,
> Boris.
>
> Sent from a fat crate under my desk. Formatting is fine.
> --
>