Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Wed, 23 Oct 2019 13:28:40 +0100
From:   Qais Yousef <qais.yousef@arm.com>
To:     Thara Gopinath <thara.gopinath@linaro.org>
Cc:     mingo@redhat.com, peterz@infradead.org, ionela.voinescu@arm.com,
        vincent.guittot@linaro.org, rui.zhang@intel.com,
        edubezval@gmail.com, qperret@google.com,
        linux-kernel@vger.kernel.org, amit.kachhap@gmail.com,
        javi.merino@kernel.org, daniel.lezcano@linaro.org
Subject: Re: [Patch v4 4/6] sched/fair: update cpu_capcity to reflect thermal
 pressure
Message-ID: <20191023122252.dz7obopab6iizy4s@e107158-lin.cambridge.arm.com>
References: <1571776465-29763-1-git-send-email-thara.gopinath@linaro.org>
 <1571776465-29763-5-git-send-email-thara.gopinath@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <1571776465-29763-5-git-send-email-thara.gopinath@linaro.org>
User-Agent: NeoMutt/20171215
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 10/22/19 16:34, Thara Gopinath wrote:
> cpu_capacity relflects the maximum available capacity of a cpu. Thermal
> pressure on a cpu means this maximum available capacity is reduced. This
> patch reduces the average thermal pressure for a cpu from its maximum
> available capacity so that cpu_capacity reflects the actual
> available capacity.
> 
> Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
> ---
>  kernel/sched/fair.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 4f9c2cb..be3e802 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -7727,6 +7727,7 @@ static unsigned long scale_rt_capacity(struct sched_domain *sd, int cpu)
>  
>  	used = READ_ONCE(rq->avg_rt.util_avg);
>  	used += READ_ONCE(rq->avg_dl.util_avg);
> +	used += READ_ONCE(rq->avg_thermal.load_avg);

Maybe a naive question - but can we add util_avg with load_avg without
a conversion? I thought the 2 signals have different properties.

Cheers

--
Qais Yousef

>  
>  	if (unlikely(used >= max))
>  		return 1;
> -- 
> 2.1.4
>