From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0F6F317DFFA for ; Thu, 1 Oct 2026 13:55:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790862939; cv=none; b=bC1+2m5se7K72/lN4IHUEMVy2Z7OcoAFeU7gh88Htt25Iwoc/xPkKvlLGnOTu8ykk3XRMenQQgiQmoLg9p2Cu9qtglOqsXdNd9fsqXpxtvMExXu+XFpcbb0j+fAXPlHl+92/MLdTKEs8AgjyI4MAY8Tjk3RRH9TXrqE9FFOQo6Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790862939; c=relaxed/simple; bh=Mj6A82xzJu8yBYE0prIJv2YDKCCYc1OG1fWVviOgcKI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VIyGCXQcH/IgTEtJIAL5813VkEJHbpc6qxRK+AaNxKvvahd1e56lzp1J379EZ8xvQQGDKfVyyPhb4LPl5dfVZ0Tg9KmqVsvrvgi+uIEHOozHrZitG+59gmlslYrtJ8ykaq8DIazrvIqbMzQEFXfWjnBS0Q4DKvnQ76/Tbid3Oq0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=jTNLEbK/; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="jTNLEbK/" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Mj6A82xzJu8yBYE0prIJv2YDKCCYc1OG1fWVviOgcKI=; b=jTNLEbK/+p55UD2qBQKk6JZ6vU Jy40YABXM5uX1tdqUD94cCP/gagCCryBs5Jabd1eU3Gn0HO7Y3dPR11uvYiwI/Bk+yK1v1A/xd6ru Ah0P4/DWBdgMoimbGn2eCCb1ZT7wpmvqBjHvZtGO7+Gr1O1+eQPZTHppyiGzQMIYoVgwUBj+y0yMc EbDbk4duggBG6Qm5vjtWXA1zOxO7McXpiAcFLlOJewV87p/SdSgXzcwXj560qkp1xJRQ3Siv3j4/Z FQTaJFYVNEcl3cIxYkPxiaU6q5qUgSwx9md81qOrNM1wpqX238pF+Lvy17BYCD2YeF1Vg6wog3RW9 41CDAR2w==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.99.2 #2 (Red Hat Linux)) id 1xCHFy-000000052qC-2ZiB; Thu, 01 Oct 2026 13:55:30 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 2E126300578; Thu, 01 Oct 2026 15:55:29 +0200 (CEST) Date: Thu, 1 Oct 2026 15:55:29 +0200 From: Peter Zijlstra To: Christian Loehle 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 Subject: Re: [PATCH v2 3/5] sched/eevdf: Cap protection when current has the shortest slice Message-ID: <20261001135529.GS2009045@noisy.programming.kicks-ass.net> References: <20261001134016.3881268-1-christian.loehle@arm.com> <20261001134016.3881268-4-christian.loehle@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261001134016.3881268-4-christian.loehle@arm.com> 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.