On Tuesday, March 5, 2019 11:42:59 AM CET Quentin Perret wrote: > Hi Rafael, > > +CC Peter since we were talking about cpuinfo.*_freq recently. > > On Friday 01 Mar 2019 at 13:57:06 (+0100), Rafael J. Wysocki wrote: > > From: Rafael J. Wysocki <rafael.j.wyso...@intel.com> > > > > While the cpuinfo.max_freq value doesn't really matter for > > intel_pstate in the active mode, in the passive mode it is used by > > governors as the maximum physical frequency of the CPU and the > > results of governor computations generally depend on it. Also it > > is made available to user space via sysfs and it should match the > > current HW configuration. > > > > For this reason, make intel_pstate update cpuinfo.max_freq for all > > CPUs if it detects a global change of turbo frequency settings from > > "disable" to "enable" or the other way associated with a _PPC change > > notification from the platform firmware. > > > > Note that policy_is_inactive() and cpufreq_set_policy() need to be > > made available to it for this purpose. > > > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759 > > Reported-by: Gabriele Mazzotta <gabriele....@gmail.com> > > Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com> > > --- > > > > Update, because the patch sent previously doesn't build, due to an extra > > arg declared for intel_pstate_update_max_freq(). > > > > --- > > drivers/cpufreq/cpufreq.c | 12 ++---------- > > drivers/cpufreq/intel_pstate.c | 33 ++++++++++++++++++++++++++++++++- > > include/linux/cpufreq.h | 7 +++++++ > > 3 files changed, 41 insertions(+), 11 deletions(-) > > > > Index: linux-pm/drivers/cpufreq/intel_pstate.c > > =================================================================== > > --- linux-pm.orig/drivers/cpufreq/intel_pstate.c > > +++ linux-pm/drivers/cpufreq/intel_pstate.c > > @@ -897,6 +897,36 @@ static void intel_pstate_update_policies > > cpufreq_update_policy(cpu); > > } > > > > +static void intel_pstate_update_max_freq(unsigned int cpu) > > +{ > > + struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); > > + struct cpufreq_policy new_policy; > > + struct cpudata *cpudata; > > + > > + if (!policy) > > + return; > > + > > + down_write(&policy->rwsem); > > + > > + if (policy_is_inactive(policy)) > > + goto unlock; > > + > > + cpudata = all_cpu_data[cpu]; > > + policy->cpuinfo.max_freq = global.turbo_disabled_upd ? > > + cpudata->pstate.max_freq : cpudata->pstate.turbo_freq; > > + > > + memcpy(&new_policy, policy, sizeof(*policy)); > > + new_policy.max = min(policy->user_policy.max, policy->cpuinfo.max_freq); > > + new_policy.min = min(policy->user_policy.min, new_policy.max); > > + > > + cpufreq_set_policy(policy, &new_policy); > > Do you want to force-restart the governor here ?
cpufreq_set_policy() is expected to take care of the governor. If it doesn't, there is a bug somewhere. > Schedutil caches cpuinfo.max_freq for the iowait stuff in sugov_start() [1]. If it does so, it should update the cached value in sugov_limits(). I guess I can add a patch updating it to this series. > I'm not sure about the other governors. They don't do that AFAICS. > And just removing sg_cpu->iowait_boost_max to use the cpuinfo struct > instead will conflict with [2], I think. Thanks for pointing this out. Cheers, Rafael
