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

[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