RE: [PATCH v9 03/13] cpufreq: intel_pstate: use common macro definition for Energy Preference Performance(EPP)

From: Yuan, Perry
Date: Thu Jan 05 2023 - 01:14:44 EST


[AMD Official Use Only - General]

Hi Mario.

> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello@xxxxxxx>
> Sent: Thursday, January 5, 2023 1:56 PM
> To: Yuan, Perry <Perry.Yuan@xxxxxxx>; rafael.j.wysocki@xxxxxxxxx; Huang,
> Ray <Ray.Huang@xxxxxxx>; viresh.kumar@xxxxxxxxxx
> Cc: Sharma, Deepak <Deepak.Sharma@xxxxxxx>; Fontenot, Nathan
> <Nathan.Fontenot@xxxxxxx>; Deucher, Alexander
> <Alexander.Deucher@xxxxxxx>; Huang, Shimmer
> <Shimmer.Huang@xxxxxxx>; Du, Xiaojian <Xiaojian.Du@xxxxxxx>; Meng,
> Li (Jassmine) <Li.Meng@xxxxxxx>; Karny, Wyes <Wyes.Karny@xxxxxxx>;
> linux-pm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v9 03/13] cpufreq: intel_pstate: use common macro
> definition for Energy Preference Performance(EPP)
>
> On 1/4/23 23:49, Yuan, Perry wrote:
> > [AMD Official Use Only - General]
> >
> > Hi Mario
> >
> >> -----Original Message-----
> >> From: Limonciello, Mario <Mario.Limonciello@xxxxxxx>
> >> Sent: Wednesday, January 4, 2023 8:31 AM
> >> To: Yuan, Perry <Perry.Yuan@xxxxxxx>; rafael.j.wysocki@xxxxxxxxx;
> >> Huang, Ray <Ray.Huang@xxxxxxx>; viresh.kumar@xxxxxxxxxx
> >> Cc: Sharma, Deepak <Deepak.Sharma@xxxxxxx>; Fontenot, Nathan
> >> <Nathan.Fontenot@xxxxxxx>; Deucher, Alexander
> >> <Alexander.Deucher@xxxxxxx>; Huang, Shimmer
> <Shimmer.Huang@xxxxxxx>;
> >> Du, Xiaojian <Xiaojian.Du@xxxxxxx>; Meng, Li (Jassmine)
> >> <Li.Meng@xxxxxxx>; Karny, Wyes <Wyes.Karny@xxxxxxx>;
> >> linux-pm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> >> Subject: Re: [PATCH v9 03/13] cpufreq: intel_pstate: use common macro
> >> definition for Energy Preference Performance(EPP)
> >>
> >> On 12/25/2022 10:34, Perry Yuan wrote:
> >>> make the energy preference performance strings and profiles using
> >>> one common header for intel_pstate driver, then the amd_pstate epp
> >>> driver can use the common header as well. This will simpify the
> >>> intel_pstate and amd_pstate driver.
> >>>
> >>> Signed-off-by: Perry Yuan <perry.yuan@xxxxxxx>
> >>> ---
> >>> drivers/cpufreq/Kconfig.x86 | 2 +-
> >>> drivers/cpufreq/intel_pstate.c | 13 +++----------
> >>> include/linux/cpufreq.h | 10 ++++++++++
> >>> 3 files changed, 14 insertions(+), 11 deletions(-)
> >>>
> >>> diff --git a/drivers/cpufreq/Kconfig.x86
> >>> b/drivers/cpufreq/Kconfig.x86 index 00476e94db90..f64aef1e093d
> >>> 100644
> >>> --- a/drivers/cpufreq/Kconfig.x86
> >>> +++ b/drivers/cpufreq/Kconfig.x86
> >>> @@ -36,7 +36,7 @@ config X86_PCC_CPUFREQ
> >>>
> >>> config X86_AMD_PSTATE
> >>> bool "AMD Processor P-State driver"
> >>> - depends on X86 && ACPI
> >>> + depends on X86 && ACPI && X86_INTEL_PSTATE
> >>
> >> This doesn't seem right to me. What if someone didn't compile in
> >> Intel
> >> x86 support for their kernel? They wouldn't be able to pick
> >> X86_AMD_PSTATE.
> >
> > How about changed like this ? when amd pstate enabled, it will build intel-
> pstate.c as well.
> >
> > depends on X86 && ACPI
> > + select X86_INTEL_PSTATE
>
> I still don't think that's the right way to do this. Why not move the variables
> to the cppc library file? Both intel and amd pstate drivers select it, so it can
> be a common place both wil use.
>
That will be good then.
Ray suggested to put the code to cpufreq.h , I will move the code to cppc library in v10 if he has no objection.

Perry.

>
> >
> >
> >
> >>
> >>> select ACPI_PROCESSOR
> >>> select ACPI_CPPC_LIB if X86_64
> >>> select CPU_FREQ_GOV_SCHEDUTIL if SMP diff --git
> >>> a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
> >>> index ad9be31753b6..93a60fdac0fc 100644
> >>> --- a/drivers/cpufreq/intel_pstate.c
> >>> +++ b/drivers/cpufreq/intel_pstate.c
> >>> @@ -640,15 +640,7 @@ static int intel_pstate_set_epb(int cpu, s16 pref)
> >>> * 4 power
> >>> */
> >>>
> >>> -enum energy_perf_value_index {
> >>> - EPP_INDEX_DEFAULT = 0,
> >>> - EPP_INDEX_PERFORMANCE,
> >>> - EPP_INDEX_BALANCE_PERFORMANCE,
> >>> - EPP_INDEX_BALANCE_POWERSAVE,
> >>> - EPP_INDEX_POWERSAVE,
> >>> -};
> >>> -
> >>> -static const char * const energy_perf_strings[] = {
> >>> +const char * const energy_perf_strings[] = {
> >>> [EPP_INDEX_DEFAULT] = "default",
> >>> [EPP_INDEX_PERFORMANCE] = "performance",
> >>> [EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance",
> >> @@ -656,7
> >>> +648,8 @@ static const char * const energy_perf_strings[] = {
> >>> [EPP_INDEX_POWERSAVE] = "power",
> >>> NULL
> >>> };
> >>> -static unsigned int epp_values[] = {
> >>> +
> >>> +unsigned int epp_values[] = {
> >>> [EPP_INDEX_DEFAULT] = 0, /* Unused index */
> >>> [EPP_INDEX_PERFORMANCE] = HWP_EPP_PERFORMANCE,
> >>> [EPP_INDEX_BALANCE_PERFORMANCE] =
> >> HWP_EPP_BALANCE_PERFORMANCE, diff
> >>> --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index
> >>> d5595d57f4e5..0693269fb775 100644
> >>> --- a/include/linux/cpufreq.h
> >>> +++ b/include/linux/cpufreq.h
> >>> @@ -185,6 +185,16 @@ struct cpufreq_freqs {
> >>> u8 flags; /* flags of cpufreq_driver, see below. */
> >>> };
> >>>
> >>> +enum energy_perf_value_index {
> >>> + EPP_INDEX_DEFAULT = 0,
> >>> + EPP_INDEX_PERFORMANCE,
> >>> + EPP_INDEX_BALANCE_PERFORMANCE,
> >>> + EPP_INDEX_BALANCE_POWERSAVE,
> >>> + EPP_INDEX_POWERSAVE,
> >>> +};
> >>> +extern const char * const energy_perf_strings[]; extern unsigned
> >>> +int epp_values[];
> >>> +
> >>> /* Only for ACPI */
> >>> #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
> >>> #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed
> >> coordination */
> >>
> >> I think the right place for these variables and strings is in the
> >> cppc library source file that is common across CPPC implementations.