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Message-ID: <7537e534-9616-4f45-9974-399453aee276@gmail.com>
Date:   Thu, 2 Nov 2023 21:31:15 +0800
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Subject: Re: [PATCH] sched/fair: Track current se's EEVDF parameters
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To:     Abel Wu <wuyun.abel@bytedance.com>, mingo@redhat.com,
        peterz@infradead.org
Cc:     vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
        linux-kernel@vger.kernel.org
References: <20231101174446.90413-1-s921975628@gmail.com>
 <e9638a3f-baa0-4abb-bb61-481c539c2181@bytedance.com>
From:   Yiwei Lin <s921975628@gmail.com>
In-Reply-To: <e9638a3f-baa0-4abb-bb61-481c539c2181@bytedance.com>
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On 11/2/23 14:27, Abel Wu wrote:
> On 11/2/23 1:44 AM, s921975628@gmail.com Wrote:
>> From: Yiwei Lin <s921975628@gmail.com>
>>
>> After dequeuing the current-picked scheduling entity with
>> `__dequeue_entity`, its contribution to the EEVDF parameters
>> cfs_rq->avg_vruntime and cfs_rq->avg_load are also removed.
>> Because these should in fact be considered for the EEVDF algorithm,
>> we took curr as the special case and inserted back the contributions
>> when requests for cfs_rq->avg_vruntime and cfs_rq->avg_load.
>
> Being 'curr' means its vruntime is increasing, so does its
> contribution to avg_vruntime. And you failed to explain the
> most important part that how to commit its contribution to
> avg_vruntime (specifically in update_curr()).
>
> Regards,
>     Abel

Thanks for pointing out the missing part.  I should remember to commit back
the latest contribution at `update_curr()`. In other words, adding
delta * scale_load_down(curr->load.weight) to avg_vruntime.

Thanks,
     Yiwei Lin