From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [RFC PATCH v4 08/12] sched: Add over-utilization/tipping point
 indicator
Date: Fri, 6 Jul 2018 13:32:08 +0200
Message-ID: <20180706113208.GS2458@hirez.programming.kicks-ass.net>
References: <20180628114043.24724-1-quentin.perret@arm.com>
 <20180628114043.24724-9-quentin.perret@arm.com>
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To: Quentin Perret <quentin.perret@arm.com>
Cc: rjw@rjwysocki.net, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, gregkh@linuxfoundation.org, mingo@redhat.com, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, chris.redpath@arm.com, patrick.bellasi@arm.com, valentin.schneider@arm.com, vincent.guittot@linaro.org, thara.gopinath@linaro.org, viresh.kumar@linaro.org, tkjos@google.com, joel@joelfernandes.org, smuckle@google.com, adharmap@quicinc.com, skannan@quicinc.com, pkondeti@codeaurora.org, juri.lelli@redhat.com, edubezval@gmail.com, srinivas.pandruvada@linux.intel.com, currojerez@riseup.net, javi.merino@kernel.org
List-Id: linux-pm@vger.kernel.org

On Thu, Jun 28, 2018 at 12:40:39PM +0100, Quentin Perret wrote:
> @@ -5384,6 +5402,7 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
>  {
>  	struct cfs_rq *cfs_rq;
>  	struct sched_entity *se = &p->se;
> +	int task_new = !(flags & ENQUEUE_WAKEUP);
>  
>  	/*
>  	 * The code below (indirectly) updates schedutil which looks at
> @@ -5431,8 +5450,12 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
>  		update_cfs_group(se);
>  	}
>  
> -	if (!se)
> +	if (!se) {
>  		add_nr_running(rq, 1);
> +		if (!task_new)
> +			update_overutilized_status(rq);

I'm confused... why only for !ENQUEUE_WAKEUP and why use a local
variable for something that's used only once?

> +	}
>  
>  	hrtick_update(rq);
>  }