| Message ID | 20180509084051.12107-1-juri.lelli@redhat.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On Wednesday, May 9, 2018 10:41:54 AM CEST Viresh Kumar wrote: > On 09-05-18, 10:40, Juri Lelli wrote: > > After commit 794a56ebd9a57 ("sched/cpufreq: Change the worker kthread to > > SCHED_DEADLINE") schedutil kthreads are "ignored" for a clock frequency > > selection point of view, so the potential corner case for RT tasks is not > > possible at all now. > > > > Remove the stale comment mentioning it. > > > > Signed-off-by: Juri Lelli <juri.lelli@redhat.com> > > Cc: Ingo Molnar <mingo@redhat.com> > > Cc: Peter Zijlstra <peterz@infradead.org> > > Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> > > Cc: Viresh Kumar <viresh.kumar@linaro.org> > > Cc: Claudio Scordino <claudio@evidence.eu.com> > > Cc: Luca Abeni <luca.abeni@santannapisa.it> > > --- > > kernel/sched/cpufreq_schedutil.c | 13 ------------- > > 1 file changed, 13 deletions(-) > > > > diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c > > index d2c6083304b4..23ef19070137 100644 > > --- a/kernel/sched/cpufreq_schedutil.c > > +++ b/kernel/sched/cpufreq_schedutil.c > > @@ -396,19 +396,6 @@ static void sugov_irq_work(struct irq_work *irq_work) > > > > sg_policy = container_of(irq_work, struct sugov_policy, irq_work); > > > > - /* > > - * For RT tasks, the schedutil governor shoots the frequency to maximum. > > - * Special care must be taken to ensure that this kthread doesn't result > > - * in the same behavior. > > - * > > - * This is (mostly) guaranteed by the work_in_progress flag. The flag is > > - * updated only at the end of the sugov_work() function and before that > > - * the schedutil governor rejects all other frequency scaling requests. > > - * > > - * There is a very rare case though, where the RT thread yields right > > - * after the work_in_progress flag is cleared. The effects of that are > > - * neglected for now. > > - */ > > kthread_queue_work(&sg_policy->worker, &sg_policy->work); > > } > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Applied and pushed for 4.17-rc5.
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index d2c6083304b4..23ef19070137 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -396,19 +396,6 @@ static void sugov_irq_work(struct irq_work *irq_work) sg_policy = container_of(irq_work, struct sugov_policy, irq_work); - /* - * For RT tasks, the schedutil governor shoots the frequency to maximum. - * Special care must be taken to ensure that this kthread doesn't result - * in the same behavior. - * - * This is (mostly) guaranteed by the work_in_progress flag. The flag is - * updated only at the end of the sugov_work() function and before that - * the schedutil governor rejects all other frequency scaling requests. - * - * There is a very rare case though, where the RT thread yields right - * after the work_in_progress flag is cleared. The effects of that are - * neglected for now. - */ kthread_queue_work(&sg_policy->worker, &sg_policy->work); }
After commit 794a56ebd9a57 ("sched/cpufreq: Change the worker kthread to SCHED_DEADLINE") schedutil kthreads are "ignored" for a clock frequency selection point of view, so the potential corner case for RT tasks is not possible at all now. Remove the stale comment mentioning it. Signed-off-by: Juri Lelli <juri.lelli@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Claudio Scordino <claudio@evidence.eu.com> Cc: Luca Abeni <luca.abeni@santannapisa.it> --- kernel/sched/cpufreq_schedutil.c | 13 ------------- 1 file changed, 13 deletions(-)