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Message-ID: <4ab8d0aa-7c03-4160-a2bf-39351c394a6e@bytedance.com>
Date: Tue, 5 Mar 2024 11:15:00 +0800
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Subject: Re: Re: [PATCH 1/2] sched/eevdf: Always update V if se->on_rq when
 reweighting
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To: Tianchen Ding <dtcccc@linux.alibaba.com>, linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
 Juri Lelli <juri.lelli@redhat.com>,
 Vincent Guittot <vincent.guittot@linaro.org>,
 Dietmar Eggemann <dietmar.eggemann@arm.com>,
 Steven Rostedt <rostedt@goodmis.org>, Ben Segall <bsegall@google.com>,
 Mel Gorman <mgorman@suse.de>, Daniel Bristot de Oliveira
 <bristot@redhat.com>, Valentin Schneider <vschneid@redhat.com>
References: <20240304030042.2690-1-dtcccc@linux.alibaba.com>
 <20240304030042.2690-2-dtcccc@linux.alibaba.com>
 <ad801d18-6243-47c5-8e37-ce712ca5d0c5@bytedance.com>
 <5b863dfe-bb97-4bc9-a117-153b1ba087f0@linux.alibaba.com>
From: Abel Wu <wuyun.abel@bytedance.com>
In-Reply-To: <5b863dfe-bb97-4bc9-a117-153b1ba087f0@linux.alibaba.com>
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On 3/5/24 10:13 AM, Tianchen Ding Wrote:
> On 2024/3/4 20:06, Abel Wu wrote:
>> On 3/4/24 11:00 AM, Tianchen Ding Wrote:
>>> reweight_eevdf() needs the latest V to do accurate calculation for new
>>> ve and vd. So update V unconditionally when se is runnable.
>>
>> As this should come along with commit eab03c23c2a1, I think it would
>> be better add a Fixes tag?
>>
> 
> I'm not sure. In fact avg_vruntime_sub() in reweight_entity() was first introduced by af4cf40470c2, and at that time the algorithm about reweight was not completed...
> 

It is because before commit eab03c23c2a1, reweight didn't rely on V.