Date: Wed, 13 Dec 2017 17:19:22 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Patrick Bellasi <patrick.bellasi@arm.com>
Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
        Ingo Molnar <mingo@redhat.com>,
        "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Paul Turner <pjt@google.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Morten Rasmussen <morten.rasmussen@arm.com>,
        Juri Lelli <juri.lelli@redhat.com>, Todd Kjos <tkjos@android.com>,
        Joel Fernandes <joelaf@google.com>
Subject: Re: [PATCH v2 2/4] sched/fair: add util_est on top of PELT
Message-ID: <20171213161922.qbxq2ko5q6ttzu2p@hirez.programming.kicks-ass.net>
References: <20171205171018.9203-1-patrick.bellasi@arm.com>
 <20171205171018.9203-3-patrick.bellasi@arm.com>
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On Tue, Dec 05, 2017 at 05:10:16PM +0000, Patrick Bellasi wrote:
> @@ -562,6 +577,12 @@ struct task_struct {
>  
>  	const struct sched_class	*sched_class;
>  	struct sched_entity		se;
> +	/*
> +	 * Since we use se.avg.util_avg to update util_est fields,
> +	 * this last can benefit from being close to se which
> +	 * also defines se.avg as cache aligned.
> +	 */
> +	struct util_est			util_est;
>  	struct sched_rt_entity		rt;
>  #ifdef CONFIG_CGROUP_SCHED
>  	struct task_group		*sched_task_group;


> diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
> index b19552a212de..8371839075fa 100644
> --- a/kernel/sched/sched.h
> +++ b/kernel/sched/sched.h
> @@ -444,6 +444,7 @@ struct cfs_rq {
>  	 * CFS load tracking
>  	 */
>  	struct sched_avg avg;
> +	unsigned long util_est_runnable;
>  #ifndef CONFIG_64BIT
>  	u64 load_last_update_time_copy;
>  #endif


So you put the util_est in task_struct (not sched_entity) but the
util_est_runnable in cfs_rq (not rq). Seems inconsistent.