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* [PATCH] PM:EM: fix wrong utilization estimation in em_cpu_energy()
@ 2024-04-04 10:42 Vincent Guittot
  2024-04-04 11:05 ` Lukasz Luba
  0 siblings, 1 reply; 3+ messages in thread
From: Vincent Guittot @ 2024-04-04 10:42 UTC (permalink / raw)
  To: lukasz.luba, rafael, linux-kernel, linux-pm, dietmar.eggemann
  Cc: rui.zhang, amit.kucheria, amit.kachhap, daniel.lezcano,
	viresh.kumar, len.brown, pavel, mhiramat, qyousef, wvw,
	xuewen.yan94, Vincent Guittot

Commit 1b600da51073 ("PM: EM: Optimize em_cpu_energy() and remove division")
has added back map_util_perf() in em_cpu_energy() computation which has
been removed with the rework of scheduler/cpufreq interface.
This is wrong because sugov_effective_cpu_perf() already takes care of
mapping the utilization to a performance level.

Fixes: 1b600da51073 ("PM: EM: Optimize em_cpu_energy() and remove division")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
---
 include/linux/energy_model.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
index 770755df852f..70cd7258cd29 100644
--- a/include/linux/energy_model.h
+++ b/include/linux/energy_model.h
@@ -245,7 +245,6 @@ static inline unsigned long em_cpu_energy(struct em_perf_domain *pd,
 	 * max utilization to the allowed CPU capacity before calculating
 	 * effective performance.
 	 */
-	max_util = map_util_perf(max_util);
 	max_util = min(max_util, allowed_cpu_cap);
 
 	/*
-- 
2.34.1


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] PM:EM: fix wrong utilization estimation in em_cpu_energy()
  2024-04-04 10:42 [PATCH] PM:EM: fix wrong utilization estimation in em_cpu_energy() Vincent Guittot
@ 2024-04-04 11:05 ` Lukasz Luba
  2024-04-04 19:05   ` Rafael J. Wysocki
  0 siblings, 1 reply; 3+ messages in thread
From: Lukasz Luba @ 2024-04-04 11:05 UTC (permalink / raw)
  To: Vincent Guittot
  Cc: rui.zhang, amit.kucheria, amit.kachhap, daniel.lezcano,
	viresh.kumar, len.brown, pavel, mhiramat, qyousef, wvw,
	xuewen.yan94, rafael, linux-kernel, linux-pm, dietmar.eggemann

Hi Vincent,

On 4/4/24 11:42, Vincent Guittot wrote:
> Commit 1b600da51073 ("PM: EM: Optimize em_cpu_energy() and remove division")
> has added back map_util_perf() in em_cpu_energy() computation which has
> been removed with the rework of scheduler/cpufreq interface.
> This is wrong because sugov_effective_cpu_perf() already takes care of
> mapping the utilization to a performance level.
> 
> Fixes: 1b600da51073 ("PM: EM: Optimize em_cpu_energy() and remove division")
> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
> ---
>   include/linux/energy_model.h | 1 -
>   1 file changed, 1 deletion(-)
> 
> diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
> index 770755df852f..70cd7258cd29 100644
> --- a/include/linux/energy_model.h
> +++ b/include/linux/energy_model.h
> @@ -245,7 +245,6 @@ static inline unsigned long em_cpu_energy(struct em_perf_domain *pd,
>   	 * max utilization to the allowed CPU capacity before calculating
>   	 * effective performance.
>   	 */
> -	max_util = map_util_perf(max_util);
>   	max_util = min(max_util, allowed_cpu_cap);
>   
>   	/*

LGTM. It was developed in parallel IIRC and that change which removes
the extra margin to the util was lost from my radar. I can see it
landed first.

Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>

Regards,
Lukasz

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] PM:EM: fix wrong utilization estimation in em_cpu_energy()
  2024-04-04 11:05 ` Lukasz Luba
@ 2024-04-04 19:05   ` Rafael J. Wysocki
  0 siblings, 0 replies; 3+ messages in thread
From: Rafael J. Wysocki @ 2024-04-04 19:05 UTC (permalink / raw)
  To: Lukasz Luba, Vincent Guittot
  Cc: rui.zhang, amit.kucheria, amit.kachhap, daniel.lezcano,
	viresh.kumar, len.brown, pavel, mhiramat, qyousef, wvw,
	xuewen.yan94, rafael, linux-kernel, linux-pm, dietmar.eggemann

On Thu, Apr 4, 2024 at 1:05 PM Lukasz Luba <lukasz.luba@arm.com> wrote:
>
> Hi Vincent,
>
> On 4/4/24 11:42, Vincent Guittot wrote:
> > Commit 1b600da51073 ("PM: EM: Optimize em_cpu_energy() and remove division")
> > has added back map_util_perf() in em_cpu_energy() computation which has
> > been removed with the rework of scheduler/cpufreq interface.
> > This is wrong because sugov_effective_cpu_perf() already takes care of
> > mapping the utilization to a performance level.
> >
> > Fixes: 1b600da51073 ("PM: EM: Optimize em_cpu_energy() and remove division")
> > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
> > ---
> >   include/linux/energy_model.h | 1 -
> >   1 file changed, 1 deletion(-)
> >
> > diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
> > index 770755df852f..70cd7258cd29 100644
> > --- a/include/linux/energy_model.h
> > +++ b/include/linux/energy_model.h
> > @@ -245,7 +245,6 @@ static inline unsigned long em_cpu_energy(struct em_perf_domain *pd,
> >        * max utilization to the allowed CPU capacity before calculating
> >        * effective performance.
> >        */
> > -     max_util = map_util_perf(max_util);
> >       max_util = min(max_util, allowed_cpu_cap);
> >
> >       /*
>
> LGTM. It was developed in parallel IIRC and that change which removes
> the extra margin to the util was lost from my radar. I can see it
> landed first.
>
> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>

Applied as 6.9-rc material, thanks!

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2024-04-04 19:05 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2024-04-04 10:42 [PATCH] PM:EM: fix wrong utilization estimation in em_cpu_energy() Vincent Guittot
2024-04-04 11:05 ` Lukasz Luba
2024-04-04 19:05   ` Rafael J. Wysocki

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