linux-kernel - Re: [PATCH] PM / EM: Micro optimization in em_pd

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20201123102839.GB447993@google.com>
Date:   Mon, 23 Nov 2020 10:28:39 +0000
From:   Quentin Perret <qperret@...gle.com>
To:     Pavankumar Kondeti <pkondeti@...eaurora.org>
Cc:     linux-kernel@...r.kernel.org,
        "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        Lukasz Luba <lukasz.luba@....com>,
        Daniel Lezcano <daniel.lezcano@...aro.org>,
        "Gustavo A. R. Silva" <gustavo@...eddedor.com>
Subject: Re: [PATCH] PM / EM: Micro optimization in em_pd_energy

Hi Pavan,

On Monday 23 Nov 2020 at 15:47:57 (+0530), Pavankumar Kondeti wrote:
> When the sum of the utilization of CPUs in a power domain is zero,

s/power/performance

> return the energy as 0 without doing any computations.
> 
> Signed-off-by: Pavankumar Kondeti <pkondeti@...eaurora.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

Makes sense to me, so with nit above:

Acked-by: Quentin Perret <qperret@...gle.com>

Thanks!
Quentin