| Message ID | 20190802104628.8410-1-qais.yousef@arm.com (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Headers | show |
| Series | cpufreq: schedutil: fix equation in comment | expand |
On Fri, 2 Aug 2019 at 12:46, Qais Yousef <qais.yousef@arm.com> wrote: > > scale_irq_capacity() call in schedutil_cpu_util() does > > util *= (max - irq) > util /= max > > But the comment says > > util *= (1 - irq) > util /= max > > Fix the comment to match what the scaling function does. > > Signed-off-by: Qais Yousef <qais.yousef@arm.com> FWIW Acked-by: Vincent Guittot <vincent.guittot@linaro.org> > --- > kernel/sched/cpufreq_schedutil.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c > index 636ca6f88c8e..e127d89d5974 100644 > --- a/kernel/sched/cpufreq_schedutil.c > +++ b/kernel/sched/cpufreq_schedutil.c > @@ -259,9 +259,9 @@ unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, > * irq metric. Because IRQ/steal time is hidden from the task clock we > * need to scale the task numbers: > * > - * 1 - irq > - * U' = irq + ------- * U > - * max > + * max - irq > + * U' = irq + --------- * U > + * max > */ > util = scale_irq_capacity(util, irq, max); > util += irq; > -- > 2.17.1 >
On 02-08-19, 11:46, Qais Yousef wrote: > scale_irq_capacity() call in schedutil_cpu_util() does > > util *= (max - irq) > util /= max > > But the comment says > > util *= (1 - irq) > util /= max > > Fix the comment to match what the scaling function does. > > Signed-off-by: Qais Yousef <qais.yousef@arm.com> > --- > kernel/sched/cpufreq_schedutil.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c > index 636ca6f88c8e..e127d89d5974 100644 > --- a/kernel/sched/cpufreq_schedutil.c > +++ b/kernel/sched/cpufreq_schedutil.c > @@ -259,9 +259,9 @@ unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, > * irq metric. Because IRQ/steal time is hidden from the task clock we > * need to scale the task numbers: > * > - * 1 - irq > - * U' = irq + ------- * U > - * max > + * max - irq > + * U' = irq + --------- * U > + * max > */ > util = scale_irq_capacity(util, irq, max); > util += irq; Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
On Fri, Aug 02, 2019 at 11:46:28AM +0100, Qais Yousef wrote: > scale_irq_capacity() call in schedutil_cpu_util() does > > util *= (max - irq) > util /= max > > But the comment says > > util *= (1 - irq) > util /= max > > Fix the comment to match what the scaling function does. > > Signed-off-by: Qais Yousef <qais.yousef@arm.com> Thanks!
On Monday, August 5, 2019 3:06:20 PM CEST Peter Zijlstra wrote: > On Fri, Aug 02, 2019 at 11:46:28AM +0100, Qais Yousef wrote: > > scale_irq_capacity() call in schedutil_cpu_util() does > > > > util *= (max - irq) > > util /= max > > > > But the comment says > > > > util *= (1 - irq) > > util /= max > > > > Fix the comment to match what the scaling function does. > > > > Signed-off-by: Qais Yousef <qais.yousef@arm.com> > > Thanks! > I've applied this, so please let me know if it has gone into -tip too and I'll drop it then.
On 08/07/19 11:42, Rafael J. Wysocki wrote: > On Monday, August 5, 2019 3:06:20 PM CEST Peter Zijlstra wrote: > > On Fri, Aug 02, 2019 at 11:46:28AM +0100, Qais Yousef wrote: > > > scale_irq_capacity() call in schedutil_cpu_util() does > > > > > > util *= (max - irq) > > > util /= max > > > > > > But the comment says > > > > > > util *= (1 - irq) > > > util /= max > > > > > > Fix the comment to match what the scaling function does. > > > > > > Signed-off-by: Qais Yousef <qais.yousef@arm.com> > > > > Thanks! > > > > I've applied this, so please let me know if it has gone into -tip too and I'll drop it then. FYI I've just got an email from tip-bot that it was committed there. Thanks! -- Qais Yousef
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 636ca6f88c8e..e127d89d5974 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -259,9 +259,9 @@ unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, * irq metric. Because IRQ/steal time is hidden from the task clock we * need to scale the task numbers: * - * 1 - irq - * U' = irq + ------- * U - * max + * max - irq + * U' = irq + --------- * U + * max */ util = scale_irq_capacity(util, irq, max); util += irq;
scale_irq_capacity() call in schedutil_cpu_util() does util *= (max - irq) util /= max But the comment says util *= (1 - irq) util /= max Fix the comment to match what the scaling function does. Signed-off-by: Qais Yousef <qais.yousef@arm.com> --- kernel/sched/cpufreq_schedutil.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)