| Message ID | 20230808081001.2215240-3-li.meng@amd.com |
|---|---|
| State | New |
| Headers | show |
| Series | AMD Pstate Preferred Core | expand |
On 8/8/2023 03:09, Meng Li wrote: > AMD Pstate driver utilizes the functions and data structures > provided by the ITMT architecture to enable the scheduler to > favor scheduling on cores which can be get a higher frequency > with lower voltage. We call it AMD Pstate Preferrred Core. > > Here sched_set_itmt_core_prio() is called to set priorities and > sched_set_itmt_support() is called to enable ITMT feature. By using this function you need to also ensure that CONFIG_SCHED_MC_PRIO has been set up in drivers/cpufreq/Kconfig.x86 when amd-pstate is used. Also I think it's worth changing arch/x86/Kconfig to: 1) Drop the requirement for CPU_SUP_INTEL 2) select X86_AMD_PSTATE > AMD Pstate driver uses the highest performance value to indicate > the priority of CPU. The higher value has a higher priority. > > The initial core rankings are set up by AMD Pstate when the > system boots. > > Add device attribute for preferred core states. > > Add one new early parameter `enable` to allow user to > enable the preferred core if the processor and power > firmware can support preferred core feature. > > Signed-off-by: Meng Li <li.meng@amd.com> > Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> > --- > drivers/cpufreq/amd-pstate.c | 149 +++++++++++++++++++++++++++++++---- > 1 file changed, 133 insertions(+), 16 deletions(-) > > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > index 9a1e194d5cf8..e919b3f4ab18 100644 > --- a/drivers/cpufreq/amd-pstate.c > +++ b/drivers/cpufreq/amd-pstate.c > @@ -37,6 +37,7 @@ > #include <linux/uaccess.h> > #include <linux/static_call.h> > #include <linux/amd-pstate.h> > +#include <linux/topology.h> > > #include <acpi/processor.h> > #include <acpi/cppc_acpi.h> > @@ -49,6 +50,8 @@ > > #define AMD_PSTATE_TRANSITION_LATENCY 20000 > #define AMD_PSTATE_TRANSITION_DELAY 1000 > +#define AMD_PSTATE_PREFCORE_THRESHOLD 166 > +#define AMD_PSTATE_MAX_CPPC_PERF 255 > > /* > * TODO: We need more time to fine tune processors with shared memory solution > @@ -65,6 +68,14 @@ static struct cpufreq_driver amd_pstate_epp_driver; > static int cppc_state = AMD_PSTATE_UNDEFINED; > static bool cppc_enabled; > > +/* > + * CPPC Preferred Core feature is supported by power firmware > + */ > +static bool prefcore_enabled = false; > + > +/* Disable AMD Pstate Preferred Core loading */ > +static bool no_prefcore __read_mostly = true; > + > /* > * AMD Energy Preference Performance (EPP) > * The EPP is used in the CCLK DPM controller to drive > @@ -290,23 +301,21 @@ static inline int amd_pstate_enable(bool enable) > static int pstate_init_perf(struct amd_cpudata *cpudata) > { > u64 cap1; > - u32 highest_perf; > > int ret = rdmsrl_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, > &cap1); > if (ret) > return ret; > > - /* > - * TODO: Introduce AMD specific power feature. > - * > - * CPPC entry doesn't indicate the highest performance in some ASICs. > + /* 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 AMD_CPPC_HIGHEST_PERF(cap1) value as > + * the default max perf. > */ > - highest_perf = amd_get_highest_perf(); > - if (highest_perf > AMD_CPPC_HIGHEST_PERF(cap1)) > - highest_perf = AMD_CPPC_HIGHEST_PERF(cap1); > - > - WRITE_ONCE(cpudata->highest_perf, highest_perf); > + if (!prefcore_enabled) > + WRITE_ONCE(cpudata->highest_perf, AMD_CPPC_HIGHEST_PERF(cap1)); > + else > + WRITE_ONCE(cpudata->highest_perf, AMD_PSTATE_PREFCORE_THRESHOLD); > > WRITE_ONCE(cpudata->nominal_perf, AMD_CPPC_NOMINAL_PERF(cap1)); > WRITE_ONCE(cpudata->lowest_nonlinear_perf, AMD_CPPC_LOWNONLIN_PERF(cap1)); > @@ -318,17 +327,15 @@ static int pstate_init_perf(struct amd_cpudata *cpudata) > static int cppc_init_perf(struct amd_cpudata *cpudata) > { > struct cppc_perf_caps cppc_perf; > - u32 highest_perf; > > int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); > if (ret) > return ret; > > - highest_perf = amd_get_highest_perf(); > - if (highest_perf > cppc_perf.highest_perf) > - highest_perf = cppc_perf.highest_perf; > - > - WRITE_ONCE(cpudata->highest_perf, highest_perf); > + if (!prefcore_enabled) > + WRITE_ONCE(cpudata->highest_perf, cppc_perf.highest_perf); > + else > + WRITE_ONCE(cpudata->highest_perf, AMD_PSTATE_PREFCORE_THRESHOLD); > > WRITE_ONCE(cpudata->nominal_perf, cppc_perf.nominal_perf); > WRITE_ONCE(cpudata->lowest_nonlinear_perf, > @@ -676,6 +683,90 @@ static void amd_perf_ctl_reset(unsigned int cpu) > wrmsrl_on_cpu(cpu, MSR_AMD_PERF_CTL, 0); > } > > +/* > + * Set AMD Pstate Preferred Core enable can't be done directly from cpufreq callbacks > + * due to locking, so queue the work for later. > + */ > +static void amd_pstste_sched_prefcore_workfn(struct work_struct *work) > +{ > + sched_set_itmt_support(); > +} > +static DECLARE_WORK(sched_prefcore_work, amd_pstste_sched_prefcore_workfn); > + > +/** > + * Get the highest performance register value. > + * @cpu: CPU from which to get highest performance. > + * @highest_perf: Return address. > + * > + * Return: 0 for success, -EIO otherwise. > + */ > +static int amd_pstate_get_highest_perf(int cpu, u64 *highest_perf) > +{ > + int ret; > + > + if (boot_cpu_has(X86_FEATURE_CPPC)) { > + u64 cap1; > + > + ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1); > + if (ret) > + return ret; > + WRITE_ONCE(*highest_perf, AMD_CPPC_HIGHEST_PERF(cap1)); > + } else { > + ret = cppc_get_highest_perf(cpu, highest_perf); > + } > + > + return (ret); > +} > + > +static void amd_pstate_init_prefcore(void) > +{ > + int cpu, ret; > + u64 highest_perf; > + > + if (no_prefcore) > + return; > + > + for_each_possible_cpu(cpu) { > + ret = amd_pstate_get_highest_perf(cpu, &highest_perf); > + if (ret) > + break; > + > + sched_set_itmt_core_prio(highest_perf, cpu); > + } > + > + /* > + * This code can be run during CPU online under the > + * CPU hotplug locks, so sched_set_amd_prefcore_support() > + * cannot be called from here. Queue up a work item > + * to invoke it. > + */ > + schedule_work(&sched_prefcore_work); > +} > + > +/* > + * Check if AMD Pstate Preferred core feature is supported and enabled > + * 1) no_prefcore is used to enable or disable AMD Pstate Preferred Core > + * loading when user would like to enable or disable it. Without that, > + * AMD Pstate Preferred Core will be disabled by default if the processor > + * and power firmware can support preferred core feature. > + * 2) prefcore_enabled is used to indicate whether CPPC preferred core is enabled. > + */ > +static void check_prefcore_supported(int cpu) > +{ > + u64 highest_perf; > + int ret; > + > + if (no_prefcore) > + return; > + > + ret = amd_pstate_get_highest_perf(cpu, &highest_perf); > + if (ret) > + return; > + > + if(highest_perf < AMD_PSTATE_MAX_CPPC_PERF) > + prefcore_enabled = true; > +} > + > static int amd_pstate_cpu_init(struct cpufreq_policy *policy) > { > int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; > @@ -697,6 +788,9 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) > > cpudata->cpu = policy->cpu; > > + /* check if CPPC preferred core feature is enabled*/ > + check_prefcore_supported(policy->cpu); > + > ret = amd_pstate_init_perf(cpudata); > if (ret) > goto free_cpudata1; > @@ -1037,6 +1131,12 @@ static ssize_t status_store(struct device *a, struct device_attribute *b, > return ret < 0 ? ret : count; > } > > +static ssize_t prefcore_state_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + return sysfs_emit(buf, "%s\n", prefcore_enabled ? "enabled" : "disabled"); > +} > + > cpufreq_freq_attr_ro(amd_pstate_max_freq); > cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq); > > @@ -1044,6 +1144,7 @@ cpufreq_freq_attr_ro(amd_pstate_highest_perf); > cpufreq_freq_attr_rw(energy_performance_preference); > cpufreq_freq_attr_ro(energy_performance_available_preferences); > static DEVICE_ATTR_RW(status); > +static DEVICE_ATTR_RO(prefcore_state); > > static struct freq_attr *amd_pstate_attr[] = { > &amd_pstate_max_freq, > @@ -1063,6 +1164,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = { > > static struct attribute *pstate_global_attributes[] = { > &dev_attr_status.attr, > + &dev_attr_prefcore_state.attr, > NULL > }; > > @@ -1114,6 +1216,9 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) > cpudata->cpu = policy->cpu; > cpudata->epp_policy = 0; > > + /* check if CPPC preferred core feature is supported*/ > + check_prefcore_supported(policy->cpu); > + > ret = amd_pstate_init_perf(cpudata); > if (ret) > goto free_cpudata1; > @@ -1506,6 +1611,8 @@ static int __init amd_pstate_init(void) > } > } > > + amd_pstate_init_prefcore(); > + > return ret; > > global_attr_free: > @@ -1527,7 +1634,17 @@ static int __init amd_pstate_param(char *str) > > return amd_pstate_set_driver(mode_idx); > } > + > +static int __init amd_prefcore_param(char *str) > +{ > + if (!strcmp(str, "enable")) > + no_prefcore = false; > + > + return 0; > +} > + > early_param("amd_pstate", amd_pstate_param); > +early_param("amd_prefcore", amd_prefcore_param); > > MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>"); > MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver");
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 9a1e194d5cf8..e919b3f4ab18 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -37,6 +37,7 @@ #include <linux/uaccess.h> #include <linux/static_call.h> #include <linux/amd-pstate.h> +#include <linux/topology.h> #include <acpi/processor.h> #include <acpi/cppc_acpi.h> @@ -49,6 +50,8 @@ #define AMD_PSTATE_TRANSITION_LATENCY 20000 #define AMD_PSTATE_TRANSITION_DELAY 1000 +#define AMD_PSTATE_PREFCORE_THRESHOLD 166 +#define AMD_PSTATE_MAX_CPPC_PERF 255 /* * TODO: We need more time to fine tune processors with shared memory solution @@ -65,6 +68,14 @@ static struct cpufreq_driver amd_pstate_epp_driver; static int cppc_state = AMD_PSTATE_UNDEFINED; static bool cppc_enabled; +/* + * CPPC Preferred Core feature is supported by power firmware + */ +static bool prefcore_enabled = false; + +/* Disable AMD Pstate Preferred Core loading */ +static bool no_prefcore __read_mostly = true; + /* * AMD Energy Preference Performance (EPP) * The EPP is used in the CCLK DPM controller to drive @@ -290,23 +301,21 @@ static inline int amd_pstate_enable(bool enable) static int pstate_init_perf(struct amd_cpudata *cpudata) { u64 cap1; - u32 highest_perf; int ret = rdmsrl_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, &cap1); if (ret) return ret; - /* - * TODO: Introduce AMD specific power feature. - * - * CPPC entry doesn't indicate the highest performance in some ASICs. + /* 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 AMD_CPPC_HIGHEST_PERF(cap1) value as + * the default max perf. */ - highest_perf = amd_get_highest_perf(); - if (highest_perf > AMD_CPPC_HIGHEST_PERF(cap1)) - highest_perf = AMD_CPPC_HIGHEST_PERF(cap1); - - WRITE_ONCE(cpudata->highest_perf, highest_perf); + if (!prefcore_enabled) + WRITE_ONCE(cpudata->highest_perf, AMD_CPPC_HIGHEST_PERF(cap1)); + else + WRITE_ONCE(cpudata->highest_perf, AMD_PSTATE_PREFCORE_THRESHOLD); WRITE_ONCE(cpudata->nominal_perf, AMD_CPPC_NOMINAL_PERF(cap1)); WRITE_ONCE(cpudata->lowest_nonlinear_perf, AMD_CPPC_LOWNONLIN_PERF(cap1)); @@ -318,17 +327,15 @@ static int pstate_init_perf(struct amd_cpudata *cpudata) static int cppc_init_perf(struct amd_cpudata *cpudata) { struct cppc_perf_caps cppc_perf; - u32 highest_perf; int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); if (ret) return ret; - highest_perf = amd_get_highest_perf(); - if (highest_perf > cppc_perf.highest_perf) - highest_perf = cppc_perf.highest_perf; - - WRITE_ONCE(cpudata->highest_perf, highest_perf); + if (!prefcore_enabled) + WRITE_ONCE(cpudata->highest_perf, cppc_perf.highest_perf); + else + WRITE_ONCE(cpudata->highest_perf, AMD_PSTATE_PREFCORE_THRESHOLD); WRITE_ONCE(cpudata->nominal_perf, cppc_perf.nominal_perf); WRITE_ONCE(cpudata->lowest_nonlinear_perf, @@ -676,6 +683,90 @@ static void amd_perf_ctl_reset(unsigned int cpu) wrmsrl_on_cpu(cpu, MSR_AMD_PERF_CTL, 0); } +/* + * Set AMD Pstate Preferred Core enable can't be done directly from cpufreq callbacks + * due to locking, so queue the work for later. + */ +static void amd_pstste_sched_prefcore_workfn(struct work_struct *work) +{ + sched_set_itmt_support(); +} +static DECLARE_WORK(sched_prefcore_work, amd_pstste_sched_prefcore_workfn); + +/** + * Get the highest performance register value. + * @cpu: CPU from which to get highest performance. + * @highest_perf: Return address. + * + * Return: 0 for success, -EIO otherwise. + */ +static int amd_pstate_get_highest_perf(int cpu, u64 *highest_perf) +{ + int ret; + + if (boot_cpu_has(X86_FEATURE_CPPC)) { + u64 cap1; + + ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1); + if (ret) + return ret; + WRITE_ONCE(*highest_perf, AMD_CPPC_HIGHEST_PERF(cap1)); + } else { + ret = cppc_get_highest_perf(cpu, highest_perf); + } + + return (ret); +} + +static void amd_pstate_init_prefcore(void) +{ + int cpu, ret; + u64 highest_perf; + + if (no_prefcore) + return; + + for_each_possible_cpu(cpu) { + ret = amd_pstate_get_highest_perf(cpu, &highest_perf); + if (ret) + break; + + sched_set_itmt_core_prio(highest_perf, cpu); + } + + /* + * This code can be run during CPU online under the + * CPU hotplug locks, so sched_set_amd_prefcore_support() + * cannot be called from here. Queue up a work item + * to invoke it. + */ + schedule_work(&sched_prefcore_work); +} + +/* + * Check if AMD Pstate Preferred core feature is supported and enabled + * 1) no_prefcore is used to enable or disable AMD Pstate Preferred Core + * loading when user would like to enable or disable it. Without that, + * AMD Pstate Preferred Core will be disabled by default if the processor + * and power firmware can support preferred core feature. + * 2) prefcore_enabled is used to indicate whether CPPC preferred core is enabled. + */ +static void check_prefcore_supported(int cpu) +{ + u64 highest_perf; + int ret; + + if (no_prefcore) + return; + + ret = amd_pstate_get_highest_perf(cpu, &highest_perf); + if (ret) + return; + + if(highest_perf < AMD_PSTATE_MAX_CPPC_PERF) + prefcore_enabled = true; +} + static int amd_pstate_cpu_init(struct cpufreq_policy *policy) { int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; @@ -697,6 +788,9 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) cpudata->cpu = policy->cpu; + /* check if CPPC preferred core feature is enabled*/ + check_prefcore_supported(policy->cpu); + ret = amd_pstate_init_perf(cpudata); if (ret) goto free_cpudata1; @@ -1037,6 +1131,12 @@ static ssize_t status_store(struct device *a, struct device_attribute *b, return ret < 0 ? ret : count; } +static ssize_t prefcore_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%s\n", prefcore_enabled ? "enabled" : "disabled"); +} + cpufreq_freq_attr_ro(amd_pstate_max_freq); cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq); @@ -1044,6 +1144,7 @@ cpufreq_freq_attr_ro(amd_pstate_highest_perf); cpufreq_freq_attr_rw(energy_performance_preference); cpufreq_freq_attr_ro(energy_performance_available_preferences); static DEVICE_ATTR_RW(status); +static DEVICE_ATTR_RO(prefcore_state); static struct freq_attr *amd_pstate_attr[] = { &amd_pstate_max_freq, @@ -1063,6 +1164,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = { static struct attribute *pstate_global_attributes[] = { &dev_attr_status.attr, + &dev_attr_prefcore_state.attr, NULL }; @@ -1114,6 +1216,9 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) cpudata->cpu = policy->cpu; cpudata->epp_policy = 0; + /* check if CPPC preferred core feature is supported*/ + check_prefcore_supported(policy->cpu); + ret = amd_pstate_init_perf(cpudata); if (ret) goto free_cpudata1; @@ -1506,6 +1611,8 @@ static int __init amd_pstate_init(void) } } + amd_pstate_init_prefcore(); + return ret; global_attr_free: @@ -1527,7 +1634,17 @@ static int __init amd_pstate_param(char *str) return amd_pstate_set_driver(mode_idx); } + +static int __init amd_prefcore_param(char *str) +{ + if (!strcmp(str, "enable")) + no_prefcore = false; + + return 0; +} + early_param("amd_pstate", amd_pstate_param); +early_param("amd_prefcore", amd_prefcore_param); MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>"); MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver");