[RESEND PATCH V3] PM / EM: Micro optimization in em_cpu_energy

[RESEND PATCH V3] PM / EM: Micro optimization in em_cpu_energy

[Pavankumar Kondeti]

When the sum of the utilization of CPUs in a power domain is zero,
return the energy as 0 without doing any computations.

Acked-by: Quentin Perret <qperret@google.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
---
 include/linux/energy_model.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
index b67a51c..8810f1f 100644
--- a/include/linux/energy_model.h
+++ b/include/linux/energy_model.h
@@ -103,6 +103,9 @@ static inline unsigned long em_cpu_energy(struct em_perf_domain *pd,
 	struct em_perf_state *ps;
 	int i, cpu;
 
+	if (!sum_util)
+		return 0;
+
 	/*
 	 * In order to predict the performance state, map the utilization of
 	 * the most utilized CPU of the performance domain to a requested
-- 
Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [RESEND PATCH V3] PM / EM: Micro optimization in em_cpu_energy

[Rafael J. Wysocki]

On Sat, Nov 28, 2020 at 3:21 AM Pavankumar Kondeti
<pkondeti@codeaurora.org> wrote:
>
> When the sum of the utilization of CPUs in a power domain is zero,
> return the energy as 0 without doing any computations.
>
> Acked-by: Quentin Perret <qperret@google.com>
> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
> Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
> ---
>  include/linux/energy_model.h | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
> index b67a51c..8810f1f 100644
> --- a/include/linux/energy_model.h
> +++ b/include/linux/energy_model.h
> @@ -103,6 +103,9 @@ static inline unsigned long em_cpu_energy(struct em_perf_domain *pd,
>         struct em_perf_state *ps;
>         int i, cpu;
>
> +       if (!sum_util)
> +               return 0;
> +
>         /*
>          * In order to predict the performance state, map the utilization of
>          * the most utilized CPU of the performance domain to a requested
> --

Applied as 5.11 material, thanks!