RE: [PATCH V11 5/7] cpufreq: amd-pstate: Update amd-pstate preferred core ranking dynamically

Yuan, Perry
2023-11-30T05:49:17Z

[AMD Official Use Only - General]

> -----Original Message-----
> From: Meng, Li (Jassmine) <Li.Meng@amd.com>
> Sent: Wednesday, November 29, 2023 2:55 PM
> To: Rafael J . Wysocki <rafael.j.wysocki@intel.com>; Huang, Ray
> <Ray.Huang@amd.com>
> Cc: linux-pm@vger.kernel.org; linux-kernel@vger.kernel.org; x86@kernel.org;
> linux-acpi@vger.kernel.org; Shuah Khan <skhan@linuxfoundation.org>; linux-
> kselftest@vger.kernel.org; Fontenot, Nathan <Nathan.Fontenot@amd.com>;
> Sharma, Deepak <Deepak.Sharma@amd.com>; Deucher, Alexander
> <Alexander.Deucher@amd.com>; Limonciello, Mario
> <Mario.Limonciello@amd.com>; Huang, Shimmer
> <Shimmer.Huang@amd.com>; Yuan, Perry <Perry.Yuan@amd.com>; Du,
> Xiaojian <Xiaojian.Du@amd.com>; Viresh Kumar <viresh.kumar@linaro.org>;
> Borislav Petkov <bp@alien8.de>; Oleksandr Natalenko
> <oleksandr@natalenko.name>; Meng, Li (Jassmine) <Li.Meng@amd.com>;
> Karny, Wyes <Wyes.Karny@amd.com>
> Subject: [PATCH V11 5/7] cpufreq: amd-pstate: Update amd-pstate preferred
> core ranking dynamically
>
> Preferred core rankings can be changed dynamically by the platform based on
> the workload and platform conditions and accounting for thermals and aging.
> When this occurs, cpu priority need to be set.
>
> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
> Reviewed-by: Wyes Karny <wyes.karny@amd.com>
> Reviewed-by: Huang Rui <ray.huang@amd.com>
> Signed-off-by: Meng Li <li.meng@amd.com>
> ---
> drivers/cpufreq/amd-pstate.c | 46
> ++++++++++++++++++++++++++++++++++++
> include/linux/amd-pstate.h | 6 +++++
> 2 files changed, 52 insertions(+)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 74dcf63d75f9..88df6510dcc0 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -312,6 +312,7 @@ static int pstate_init_perf(struct amd_cpudata
> *cpudata)
> WRITE_ONCE(cpudata->nominal_perf,
> AMD_CPPC_NOMINAL_PERF(cap1));
> WRITE_ONCE(cpudata->lowest_nonlinear_perf,
> AMD_CPPC_LOWNONLIN_PERF(cap1));
> WRITE_ONCE(cpudata->lowest_perf,
> AMD_CPPC_LOWEST_PERF(cap1));
> + WRITE_ONCE(cpudata->prefcore_ranking,
> AMD_CPPC_HIGHEST_PERF(cap1));
>
> return 0;
> }
> @@ -333,6 +334,7 @@ static int cppc_init_perf(struct amd_cpudata
> *cpudata)
> WRITE_ONCE(cpudata->lowest_nonlinear_perf,
> cppc_perf.lowest_nonlinear_perf);
> WRITE_ONCE(cpudata->lowest_perf, cppc_perf.lowest_perf);
> + WRITE_ONCE(cpudata->prefcore_ranking, cppc_perf.highest_perf);
>
> if (cppc_state == AMD_PSTATE_ACTIVE)
> return 0;
> @@ -749,6 +751,34 @@ static void amd_pstate_init_prefcore(struct
> amd_cpudata *cpudata)
> schedule_work(&sched_prefcore_work);
> }
>
> +static void amd_pstate_update_highest_perf(unsigned int cpu) {
> + struct cpufreq_policy *policy;
> + struct amd_cpudata *cpudata;
> + u32 prev_high = 0, cur_high = 0;
> + int ret;
> +
> + if ((!amd_pstate_prefcore) || (!cpudata->hw_prefcore))
> + return;
> +
> + ret = amd_pstate_get_highest_perf(cpu, &cur_high);
> + if (ret)
> + return;
> +
> + policy = cpufreq_cpu_get(cpu);
> + cpudata = policy->driver_data;
> + prev_high = READ_ONCE(cpudata->prefcore_ranking);
> +
> + if (prev_high != cur_high) {
> + WRITE_ONCE(cpudata->prefcore_ranking, cur_high);
> +
> + if (cur_high < CPPC_MAX_PERF)
> + sched_set_itmt_core_prio((int)cur_high, cpu);
> + }
> +
> + cpufreq_cpu_put(policy);
> +}
> +
> static int amd_pstate_cpu_init(struct cpufreq_policy *policy) {
> int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
> @@ -920,6 +950,17 @@ static ssize_t show_amd_pstate_highest_perf(struct
> cpufreq_policy *policy,
> return sysfs_emit(buf, "%u\n", perf);
> }
>
> +static ssize_t show_amd_pstate_prefcore_ranking(struct cpufreq_policy
> *policy,
> + char *buf)
> +{
> + u32 perf;
> + struct amd_cpudata *cpudata = policy->driver_data;
> +
> + perf = READ_ONCE(cpudata->prefcore_ranking);
> +
> + return sysfs_emit(buf, "%u\n", perf);
> +}
> +
> static ssize_t show_amd_pstate_hw_prefcore(struct cpufreq_policy *policy,
> char *buf)
> {
> @@ -1133,6 +1174,7 @@ cpufreq_freq_attr_ro(amd_pstate_max_freq);
> cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
>
> cpufreq_freq_attr_ro(amd_pstate_highest_perf);
> +cpufreq_freq_attr_ro(amd_pstate_prefcore_ranking);
> cpufreq_freq_attr_ro(amd_pstate_hw_prefcore);
> cpufreq_freq_attr_rw(energy_performance_preference);
> cpufreq_freq_attr_ro(energy_performance_available_preferences);
> @@ -1143,6 +1185,7 @@ static struct freq_attr *amd_pstate_attr[] = {
> &amd_pstate_max_freq,
> &amd_pstate_lowest_nonlinear_freq,
> &amd_pstate_highest_perf,
> + &amd_pstate_prefcore_ranking,
> &amd_pstate_hw_prefcore,
> NULL,
> };
> @@ -1151,6 +1194,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
> &amd_pstate_max_freq,
> &amd_pstate_lowest_nonlinear_freq,
> &amd_pstate_highest_perf,
> + &amd_pstate_prefcore_ranking,
> &amd_pstate_hw_prefcore,
> &energy_performance_preference,
> &energy_performance_available_preferences,
> @@ -1491,6 +1535,7 @@ static struct cpufreq_driver amd_pstate_driver = {
> .suspend = amd_pstate_cpu_suspend,
> .resume = amd_pstate_cpu_resume,
> .set_boost = amd_pstate_set_boost,
> + .update_highest_perf = amd_pstate_update_highest_perf,
> .name = "amd-pstate",
> .attr = amd_pstate_attr,
> };
> @@ -1505,6 +1550,7 @@ static struct cpufreq_driver
> amd_pstate_epp_driver = {
> .online = amd_pstate_epp_cpu_online,
> .suspend = amd_pstate_epp_suspend,
> .resume = amd_pstate_epp_resume,
> + .update_highest_perf = amd_pstate_update_highest_perf,
> .name = "amd-pstate-epp",
> .attr = amd_pstate_epp_attr,
> };
> diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h index
> 87e140e9e6db..426822612373 100644
> --- a/include/linux/amd-pstate.h
> +++ b/include/linux/amd-pstate.h
> @@ -39,11 +39,16 @@ struct amd_aperf_mperf {
> * @cppc_req_cached: cached performance request hints
> * @highest_perf: the maximum performance an individual processor may
> reach,
> * assuming ideal conditions
> + * For platforms that do not support the preferred core feature,
> the
> + * highest_pef may be configured with 166 or 255, to avoid
> max frequency
> + * calculated wrongly. we take the fixed value as the
> highest_perf.
> * @nominal_perf: the maximum sustained performance level of the
> processor,
> * assuming ideal operating conditions
> * @lowest_nonlinear_perf: the lowest performance level at which nonlinear
> power
> * savings are achieved
> * @lowest_perf: the absolute lowest performance level of the processor
> + * @prefcore_ranking: the preferred core ranking, the higher value indicates a
> higher
> + * priority.
> * @max_freq: the frequency that mapped to highest_perf
> * @min_freq: the frequency that mapped to lowest_perf
> * @nominal_freq: the frequency that mapped to nominal_perf @@ -73,6
> +78,7 @@ struct amd_cpudata {
> u32 nominal_perf;
> u32 lowest_nonlinear_perf;
> u32 lowest_perf;
> + u32 prefcore_ranking;
>
> u32 max_freq;
> u32 min_freq;
> --
> 2.34.1

Reviewed-by: Perry Yuan <perry.yuan@amd.com>