| Message ID | 2563394.lUgF3b60iC@aspire.rjw.lan (mailing list archive) |
|---|---|
| State | Mainlined |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On 22-03-17, 18:32, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > sugov_update_commit() calls trace_cpu_frequency() to record the > current CPU frequency if it has not changed in the fast switch case > to prevent utilities from getting confused (they may report that the > CPU is idle if the frequency has not been recorded for too long, for > example). > > However, that may cause the tracepoint to be triggered quite often > for no real reason (if the frequency doesn't change, we will not > modify the last update time stamp and governor computations may > run again shortly when that happens), so don't do that (arguably, it > is done to work around a utilities bug anyway). > > That allows code duplication in sugov_update_commit() to be reduced > somewhat too. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > -> v2: > Drop the trace_cpu_frequency() call in the sg_policy->next_freq == next_freq case. > > --- > kernel/sched/cpufreq_schedutil.c | 16 +++++++--------- > 1 file changed, 7 insertions(+), 9 deletions(-) Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Index: linux-pm/kernel/sched/cpufreq_schedutil.c =================================================================== --- linux-pm.orig/kernel/sched/cpufreq_schedutil.c +++ linux-pm/kernel/sched/cpufreq_schedutil.c @@ -98,22 +98,20 @@ static void sugov_update_commit(struct s { struct cpufreq_policy *policy = sg_policy->policy; + if (sg_policy->next_freq == next_freq) + return; + + sg_policy->next_freq = next_freq; + sg_policy->last_freq_update_time = time; + if (policy->fast_switch_enabled) { - if (sg_policy->next_freq == next_freq) { - trace_cpu_frequency(policy->cur, smp_processor_id()); - return; - } - sg_policy->next_freq = next_freq; - sg_policy->last_freq_update_time = time; next_freq = cpufreq_driver_fast_switch(policy, next_freq); if (next_freq == CPUFREQ_ENTRY_INVALID) return; policy->cur = next_freq; trace_cpu_frequency(next_freq, smp_processor_id()); - } else if (sg_policy->next_freq != next_freq) { - sg_policy->next_freq = next_freq; - sg_policy->last_freq_update_time = time; + } else { sg_policy->work_in_progress = true; irq_work_queue(&sg_policy->irq_work); }