On Monday, August 26, 2019 11:40:58 AM CEST Peter Zijlstra wrote:
> On Mon, Aug 26, 2019 at 11:10:52AM +0200, Rafael J. Wysocki wrote:
> > On Wednesday, August 7, 2019 5:33:40 PM CEST Douglas RAILLARD wrote:
> > > Fast switching path only emits an event for the CPU of interest, whereas
> > > the
> > > regular path emits an event for all the CPUs that had their frequency
> > > changed,
> > > i.e. all the CPUs sharing the same policy.
> > >
> > > With the current behavior, looking at cpu_frequency event for a given CPU
> > > that
> > > is using the fast switching path will not give the correct frequency
> > > signal.
> > >
> > > Signed-off-by: Douglas RAILLARD <douglas.raill...@arm.com>
> > > ---
> > > kernel/sched/cpufreq_schedutil.c | 7 ++++++-
> > > 1 file changed, 6 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/kernel/sched/cpufreq_schedutil.c
> > > b/kernel/sched/cpufreq_schedutil.c
> > > index 1f82ab108bab..975ccc3de807 100644
> > > --- a/kernel/sched/cpufreq_schedutil.c
> > > +++ b/kernel/sched/cpufreq_schedutil.c
> > > @@ -153,6 +153,7 @@ static void sugov_fast_switch(struct sugov_policy
> > > *sg_policy, u64 time,
> > > unsigned int next_freq)
> > > {
> > > struct cpufreq_policy *policy = sg_policy->policy;
> > > + int cpu;
> > >
> > > if (!sugov_update_next_freq(sg_policy, time, next_freq))
> > > return;
> > > @@ -162,7 +163,11 @@ static void sugov_fast_switch(struct sugov_policy
> > > *sg_policy, u64 time,
> > > return;
> > >
> > > policy->cur = next_freq;
> > > - trace_cpu_frequency(next_freq, smp_processor_id());
> > > +
> > > + if (trace_cpu_frequency_enabled()) {
> > > + for_each_cpu(cpu, policy->cpus)
> > > + trace_cpu_frequency(next_freq, cpu);
> > > + }
> > > }
> > >
> > > static void sugov_deferred_update(struct sugov_policy *sg_policy, u64
> > > time,
> > >
> >
> > Peter, any comments here?
>
> I was thinking this would be a static map and dealing with it would be
> something trivially done in post (or manually while reading), but sure,
> whatever:
>
> Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org>
>
Thanks, queuing up this one for 5.4.
