| Message ID | 71055380.gdY33coAtF@aspire.rjw.lan (mailing list archive) |
|---|---|
| State | Mainlined |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On 11-04-17, 00:20, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Make the schedutil governor take the initial (default) value of the > rate_limit_us sysfs attribute from the (new) transition_delay_us > policy parameter (to be set by the scaling driver). > > That will allow scaling drivers to make schedutil use smaller default > values of rate_limit_us and reduce the default average time interval > between consecutive frequency changes. > > Make intel_pstate set transition_delay_us to 500. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > This is a replacement for https://patchwork.kernel.org/patch/9671831/ > > --- > drivers/cpufreq/intel_pstate.c | 2 ++ > include/linux/cpufreq.h | 7 +++++++ > kernel/sched/cpufreq_schedutil.c | 15 ++++++++++----- > 3 files changed, 19 insertions(+), 5 deletions(-) Should we use this new value for the ondemand/conservative governors as well?
On Tue, Apr 11, 2017 at 1:14 PM, Viresh Kumar <viresh.kumar@linaro.org> wrote: > On 11-04-17, 00:20, Rafael J. Wysocki wrote: >> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> >> Make the schedutil governor take the initial (default) value of the >> rate_limit_us sysfs attribute from the (new) transition_delay_us >> policy parameter (to be set by the scaling driver). >> >> That will allow scaling drivers to make schedutil use smaller default >> values of rate_limit_us and reduce the default average time interval >> between consecutive frequency changes. >> >> Make intel_pstate set transition_delay_us to 500. >> >> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> --- >> >> This is a replacement for https://patchwork.kernel.org/patch/9671831/ >> >> --- >> drivers/cpufreq/intel_pstate.c | 2 ++ >> include/linux/cpufreq.h | 7 +++++++ >> kernel/sched/cpufreq_schedutil.c | 15 ++++++++++----- >> 3 files changed, 19 insertions(+), 5 deletions(-) > > Should we use this new value for the ondemand/conservative governors as well? We might, but it is mostly for schedutil. Thanks, Rafael
On Tuesday, April 11, 2017 12:20:41 AM Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Make the schedutil governor take the initial (default) value of the > rate_limit_us sysfs attribute from the (new) transition_delay_us > policy parameter (to be set by the scaling driver). > > That will allow scaling drivers to make schedutil use smaller default > values of rate_limit_us and reduce the default average time interval > between consecutive frequency changes. > > Make intel_pstate set transition_delay_us to 500. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > This is a replacement for https://patchwork.kernel.org/patch/9671831/ Any concerns about this one? > > --- > drivers/cpufreq/intel_pstate.c | 2 ++ > include/linux/cpufreq.h | 7 +++++++ > kernel/sched/cpufreq_schedutil.c | 15 ++++++++++----- > 3 files changed, 19 insertions(+), 5 deletions(-) > > Index: linux-pm/include/linux/cpufreq.h > =================================================================== > --- linux-pm.orig/include/linux/cpufreq.h > +++ linux-pm/include/linux/cpufreq.h > @@ -120,6 +120,13 @@ struct cpufreq_policy { > bool fast_switch_possible; > bool fast_switch_enabled; > > + /* > + * Preferred average time interval between consecutive invocations of > + * the driver to set the frequency for this policy. To be set by the > + * scaling driver (0, which is the default, means no preference). > + */ > + unsigned int transition_delay_us; > + > /* Cached frequency lookup from cpufreq_driver_resolve_freq. */ > unsigned int cached_target_freq; > int cached_resolved_idx; > Index: linux-pm/kernel/sched/cpufreq_schedutil.c > =================================================================== > --- linux-pm.orig/kernel/sched/cpufreq_schedutil.c > +++ linux-pm/kernel/sched/cpufreq_schedutil.c > @@ -491,7 +491,6 @@ static int sugov_init(struct cpufreq_pol > { > struct sugov_policy *sg_policy; > struct sugov_tunables *tunables; > - unsigned int lat; > int ret = 0; > > /* State should be equivalent to EXIT */ > @@ -530,10 +529,16 @@ static int sugov_init(struct cpufreq_pol > goto stop_kthread; > } > > - tunables->rate_limit_us = LATENCY_MULTIPLIER; > - lat = policy->cpuinfo.transition_latency / NSEC_PER_USEC; > - if (lat) > - tunables->rate_limit_us *= lat; > + if (policy->transition_delay_us) { > + tunables->rate_limit_us = policy->transition_delay_us; > + } else { > + unsigned int lat; > + > + tunables->rate_limit_us = LATENCY_MULTIPLIER; > + lat = policy->cpuinfo.transition_latency / NSEC_PER_USEC; > + if (lat) > + tunables->rate_limit_us *= lat; > + } > > policy->governor_data = sg_policy; > sg_policy->tunables = tunables; > Index: linux-pm/drivers/cpufreq/intel_pstate.c > =================================================================== > --- linux-pm.orig/drivers/cpufreq/intel_pstate.c > +++ linux-pm/drivers/cpufreq/intel_pstate.c > @@ -41,6 +41,7 @@ > #define INTEL_PSTATE_HWP_SAMPLING_INTERVAL (50 * NSEC_PER_MSEC) > > #define INTEL_CPUFREQ_TRANSITION_LATENCY 20000 > +#define INTEL_CPUFREQ_TRANSITION_DELAY 500 > > #ifdef CONFIG_ACPI > #include <acpi/processor.h> > @@ -2237,6 +2238,7 @@ static int intel_cpufreq_cpu_init(struct > return ret; > > policy->cpuinfo.transition_latency = INTEL_CPUFREQ_TRANSITION_LATENCY; > + policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY; > /* This reflects the intel_pstate_get_cpu_pstates() setting. */ > policy->cur = policy->cpuinfo.min_freq; > >
On Fri, Apr 14, 2017 at 3:51 PM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > On Tuesday, April 11, 2017 12:20:41 AM Rafael J. Wysocki wrote: >> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> >> Make the schedutil governor take the initial (default) value of the >> rate_limit_us sysfs attribute from the (new) transition_delay_us >> policy parameter (to be set by the scaling driver). >> >> That will allow scaling drivers to make schedutil use smaller default >> values of rate_limit_us and reduce the default average time interval >> between consecutive frequency changes. >> >> Make intel_pstate set transition_delay_us to 500. >> >> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> --- >> >> This is a replacement for https://patchwork.kernel.org/patch/9671831/ > > Any concerns about this one? Looks good to me. Thanks, Joel
On 11-04-17, 00:20, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Make the schedutil governor take the initial (default) value of the > rate_limit_us sysfs attribute from the (new) transition_delay_us > policy parameter (to be set by the scaling driver). > > That will allow scaling drivers to make schedutil use smaller default > values of rate_limit_us and reduce the default average time interval > between consecutive frequency changes. > > Make intel_pstate set transition_delay_us to 500. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > This is a replacement for https://patchwork.kernel.org/patch/9671831/ Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Hi Rafael, On Fri, Apr 14 2017 at 22:51, Rafael J. Wysocki wrote: > On Tuesday, April 11, 2017 12:20:41 AM Rafael J. Wysocki wrote: >> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> >> Make the schedutil governor take the initial (default) value of the >> rate_limit_us sysfs attribute from the (new) transition_delay_us >> policy parameter (to be set by the scaling driver). >> >> That will allow scaling drivers to make schedutil use smaller default >> values of rate_limit_us and reduce the default average time interval >> between consecutive frequency changes. >> >> Make intel_pstate set transition_delay_us to 500. >> >> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> --- >> >> This is a replacement for https://patchwork.kernel.org/patch/9671831/ > > Any concerns about this one? Sorry for the delay. This looked good to me. Cheers Brendan
Index: linux-pm/include/linux/cpufreq.h =================================================================== --- linux-pm.orig/include/linux/cpufreq.h +++ linux-pm/include/linux/cpufreq.h @@ -120,6 +120,13 @@ struct cpufreq_policy { bool fast_switch_possible; bool fast_switch_enabled; + /* + * Preferred average time interval between consecutive invocations of + * the driver to set the frequency for this policy. To be set by the + * scaling driver (0, which is the default, means no preference). + */ + unsigned int transition_delay_us; + /* Cached frequency lookup from cpufreq_driver_resolve_freq. */ unsigned int cached_target_freq; int cached_resolved_idx; Index: linux-pm/kernel/sched/cpufreq_schedutil.c =================================================================== --- linux-pm.orig/kernel/sched/cpufreq_schedutil.c +++ linux-pm/kernel/sched/cpufreq_schedutil.c @@ -491,7 +491,6 @@ static int sugov_init(struct cpufreq_pol { struct sugov_policy *sg_policy; struct sugov_tunables *tunables; - unsigned int lat; int ret = 0; /* State should be equivalent to EXIT */ @@ -530,10 +529,16 @@ static int sugov_init(struct cpufreq_pol goto stop_kthread; } - tunables->rate_limit_us = LATENCY_MULTIPLIER; - lat = policy->cpuinfo.transition_latency / NSEC_PER_USEC; - if (lat) - tunables->rate_limit_us *= lat; + if (policy->transition_delay_us) { + tunables->rate_limit_us = policy->transition_delay_us; + } else { + unsigned int lat; + + tunables->rate_limit_us = LATENCY_MULTIPLIER; + lat = policy->cpuinfo.transition_latency / NSEC_PER_USEC; + if (lat) + tunables->rate_limit_us *= lat; + } policy->governor_data = sg_policy; sg_policy->tunables = tunables; Index: linux-pm/drivers/cpufreq/intel_pstate.c =================================================================== --- linux-pm.orig/drivers/cpufreq/intel_pstate.c +++ linux-pm/drivers/cpufreq/intel_pstate.c @@ -41,6 +41,7 @@ #define INTEL_PSTATE_HWP_SAMPLING_INTERVAL (50 * NSEC_PER_MSEC) #define INTEL_CPUFREQ_TRANSITION_LATENCY 20000 +#define INTEL_CPUFREQ_TRANSITION_DELAY 500 #ifdef CONFIG_ACPI #include <acpi/processor.h> @@ -2237,6 +2238,7 @@ static int intel_cpufreq_cpu_init(struct return ret; policy->cpuinfo.transition_latency = INTEL_CPUFREQ_TRANSITION_LATENCY; + policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY; /* This reflects the intel_pstate_get_cpu_pstates() setting. */ policy->cur = policy->cpuinfo.min_freq;