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Date: Wed, 18 Mar 2026 13:55:22 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: John Stultz <jstultz@google.com>, LKML <linux-kernel@vger.kernel.org>,
	Joel Fernandes <joelagnelf@nvidia.com>,
	Qais Yousef <qyousef@layalina.io>, Ingo Molnar <mingo@redhat.com>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
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	Valentin Schneider <vschneid@redhat.com>,
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	Ben Segall <bsegall@google.com>,
	Zimuzo Ezeozue <zezeozue@google.com>, Mel Gorman <mgorman@suse.de>,
	Will Deacon <will@kernel.org>, Waiman Long <longman@redhat.com>,
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	kuyo chang <kuyo.chang@mediatek.com>, hupu <hupu.gm@gmail.com>,
	kernel-team@android.com
Subject: Re: [PATCH v25 1/9] sched: Make class_schedulers avoid pushing
 current, and get rid of proxy_tag_curr()
Message-ID: <20260318125522.GH3738010@noisy.programming.kicks-ass.net>
References: <20260313023022.2902479-1-jstultz@google.com>
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 <20ea3670-c30a-433b-a07f-c4ff98ae2379@amd.com>
 <CANDhNCrKs4PeT-GresZ-owaLe3eBuJtuteUKkTOviR5McXX5JQ@mail.gmail.com>
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In-Reply-To: <bb1821a5-8184-4bd6-964a-383ae3efe625@amd.com>

On Tue, Mar 17, 2026 at 11:11:20AM +0530, K Prateek Nayak wrote:

> Also, deadline, RT, fair, and idle don't really care about the "next"
> argument of put_prev_task() and the only one that does care is
> put_prev_task_scx() to call switch_class() callback so putting it as
> either NULL or "rq->donor" should be safe.

https://lkml.kernel.org/r/20260317104343.225156112@infradead.org

Makes fair care about the @next argument to put_prev_task_fair().