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Date: Thu, 1 Oct 2026 14:57:48 +0100
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Subject: Re: [PATCH v2 3/5] sched/eevdf: Cap protection when current has the
 shortest slice
To: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org, mingo@redhat.com,
 vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
 kayracizmeci@gmail.com, kprateek.nayak@amd.com, elif.topuz@arm.com,
 sh@gentwo.org
References: <20261001134016.3881268-1-christian.loehle@arm.com>
 <20261001134016.3881268-4-christian.loehle@arm.com>
 <20261001135529.GS2009045@noisy.programming.kicks-ass.net>
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From: Christian Loehle <christian.loehle@arm.com>
In-Reply-To: <20261001135529.GS2009045@noisy.programming.kicks-ass.net>
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On 10/1/26 14:55, Peter Zijlstra wrote:
> On Thu, Oct 01, 2026 at 02:40:14PM +0100, Christian Loehle wrote:
>> Changing a task slice preserves its remaining request. With
>> PLACE_REL_DEADLINE, the deadline can therefore extend beyond the new
>> slice after sched_setattr() reduces it.
> 
> Or, the new slice is only effective after the current expires.
> 
> Is there a reason we care about this? Changelog didn't mention.

Yeah I wasn't sure about this, it does make the tests a little more
hairy as this obviously races...