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

[Dietmar Eggemann <dietmar.eggemann@arm.com>]

On 23/11/2020 11:35, Pavankumar Kondeti wrote:
> When the sum of the utilization of CPUs in a performance domain is
> zero, return the energy as 0 without doing any computations.
> 
> Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
> ---
> V3: %s/power/performance as corrected by Quentin
> V2: Fixed the function name in the commit message.
> 
>  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


LGTM.

Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>