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Date: Mon, 3 Aug 2026 10:36:40 -1000
From: Tejun Heo <tj@kernel.org>
To: Andrea Righi <arighi@nvidia.com>
Cc: David Vernet <void@manifault.com>, Changwoo Min <changwoo@igalia.com>,
	John Stultz <jstultz@google.com>, 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>,
	Valentin Schneider <vschneid@redhat.com>,
	K Prateek Nayak <kprateek.nayak@amd.com>,
	Christian Loehle <christian.loehle@arm.com>,
	David Dai <david.dai@linux.dev>, Koba Ko <kobak@nvidia.com>,
	Aiqun Yu <aiqun.yu@oss.qualcomm.com>, Shuah Khan <shuah@kernel.org>,
	sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 07/15] sched_ext: Block proxy donors across scheduler
 transitions
Message-ID: <anD72EDnXYgSg5Eg@slm.duckdns.org>
References: <20260728154425.1549660-1-arighi@nvidia.com>
 <20260728154425.1549660-8-arighi@nvidia.com>
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In-Reply-To: <20260728154425.1549660-8-arighi@nvidia.com>

On Tue, Jul 28, 2026 at 05:43:25PM +0200, Andrea Righi wrote:
...
> +static void prepare_switch_scx(struct rq *rq, struct task_struct *p)
> +{
> +	lockdep_assert_held(&p->pi_lock);
> +	lockdep_assert_rq_held(rq);
> +
> +	sched_proxy_block_task(rq, p);
>  }

Are there use cases where proxy execution instance needs to survive across
class changes (the mutex rt PI, maybe)? If not, maybe this can be the global
behavior?

Thanks.

-- 
tejun