On 05-07-17, 09:59, Juri Lelli wrote: > No assumption can be made upon the rate at which frequency updates get > triggered, as there are scheduling policies (like SCHED_DEADLINE) which > don't trigger them so frequently. > > Remove such assumption from the code, by always considering > SCHED_DEADLINE utilization signal as not stale. > > Signed-off-by: Juri Lelli <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Ingo Molnar <[email protected]> > Cc: Rafael J. Wysocki <[email protected]> > Cc: Viresh Kumar <[email protected]> > Cc: Luca Abeni <[email protected]> > Cc: Claudio Scordino <[email protected]> > --- > kernel/sched/cpufreq_schedutil.c | 17 +++++++++++------ > 1 file changed, 11 insertions(+), 6 deletions(-) > > diff --git a/kernel/sched/cpufreq_schedutil.c > b/kernel/sched/cpufreq_schedutil.c > index e835fa886225..066b876d81e7 100644 > --- a/kernel/sched/cpufreq_schedutil.c > +++ b/kernel/sched/cpufreq_schedutil.c > @@ -267,17 +267,22 @@ static unsigned int sugov_next_freq_shared(struct > sugov_cpu *sg_cpu, u64 time) > s64 delta_ns; > > /* > - * If the CPU utilization was last updated before the previous > - * frequency update and the time elapsed between the last update > - * of the CPU utilization and the last frequency update is long > - * enough, don't take the CPU into account as it probably is > - * idle now (and clear iowait_boost for it). > + * If the CFS CPU utilization was last updated before the > + * previous frequency update and the time elapsed between the > + * last update of the CPU utilization and the last frequency > + * update is long enough, reset iowait_boost and util_cfs, as > + * they are now probably stale. However, still consider the > + * CPU contribution if it has some DEADLINE utilization > + * (util_dl). > */ > delta_ns = time - j_sg_cpu->last_update; > if (delta_ns > TICK_NSEC) { > j_sg_cpu->iowait_boost = 0; > - continue; > + j_sg_cpu->util_cfs = 0; > + if (j_sg_cpu->util_dl == 0) > + continue; > } > + > if (j_sg_cpu->flags & SCHED_CPUFREQ_RT) > return policy->cpuinfo.max_freq; >
Acked-by: Viresh Kumar <[email protected]> -- viresh
