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Date: Thu, 10 Sep 2026 12:12:22 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Andrea Righi <arighi@nvidia.com>
Cc: Tejun Heo <tj@kernel.org>, David Vernet <void@manifault.com>,
	Changwoo Min <changwoo@igalia.com>,
	John Stultz <jstultz@google.com>, Ingo Molnar <mingo@redhat.com>,
	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>,
	Valentin Schneider <vschneid@redhat.com>,
	K Prateek Nayak <kprateek.nayak@amd.com>,
	Christian Loehle <christian.loehle@arm.com>,
	David Dai <david.dai@linux.dev>, Emil Tsalapatis <etsal@meta.com>,
	Lee Trager <ltrager@nvidia.com>, Richard Cheng <icheng@nvidia.com>,
	Koba Ko <kobak@nvidia.com>, Aiqun Yu <aiqun.yu@oss.qualcomm.com>,
	sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 05/18] sched: Pass next class to sched_change_begin()
Message-ID: <20260910101222.GG4120091@noisy.programming.kicks-ass.net>
References: <20260831134338.1531664-1-arighi@nvidia.com>
 <20260831134338.1531664-6-arighi@nvidia.com>
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In-Reply-To: <20260831134338.1531664-6-arighi@nvidia.com>

On Mon, Aug 31, 2026 at 03:42:15PM +0200, Andrea Righi wrote:
> sched_change_begin() currently only receives the task whose scheduling
> state is being changed. It cannot distinguish a class transition from a
> same-class update before recording the task queueing state.

Uh, yes it can. That's what {EN,DE}QUEUE_CLASS are for, no?