From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 CFE9B3DF002 for ; Fri, 26 Jun 2026 07:21:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782458497; cv=none; b=bgBNLOUL7rRaZYPJBe4ckFSkScSL9XfveET9M3KYhAVGStxbGWRCBxd26jbJoH8u8pP7D+DpbPmlVtzsOUZIkAsuMMnyLAveh67+75HRukjq9cYEn5wkMZuJl3AGZypiGdVmSYw4G7YU+UkBccBNF/WGu0Pymj3MVyAMDPQ05SY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782458497; c=relaxed/simple; bh=ltyEqJsLHJn97YsZVvCJTPgBM2dMp9/wa1u/ZZb3/n0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WYI+n49e6TFoHm6ykaJnu461Zv18cbXAsROynJ0uIdvU+KCutssJF6Nia63hdnTRdPcMY0o0A7TynhN+efafgn2T9GJIgwPwOirr0qyzHvmW0c6E2amA606Efcuj8O6V/sOqM2FZ5hXNoTSRH5xrwIBr7eLM11k4FYQ8hFsfLEo= 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=ZC7Ecfac; arc=none smtp.client-ip=90.155.50.34 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="ZC7Ecfac" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=/qY1gJqb81Ve8fgbPeIZGoFFUGsaI4djqohl5yYxd0Y=; b=ZC7EcfacdqZ34mNCvBRJSh6Pza xzMbgHO5FuhnCYiRFugPPn/B82I99sK93tHjB3A7EekjUlfdUmaRwlhde8IuJxanltTdh8Bx7IZ2J rKIjNgGrVkh3sEeXde0GBhonDM+xuYgr2iqeTEHpSUv1oeQmneLLvqW6vV5yMosoOEWn/Eon0Ppaa 5IHxaSaVhcLRVYNKT2ak7pf+lN7Q0EcNmfELTDHd1MiK+7t0GW4xn7Tjw/AShCKZB1Js+5TmEB1Wm Z2/1onUNvOgM0a5/KVK4XTfE3uivth8OPeKDMdzJq7Yz2BhoSKo20kyGFAY35uIxBYMahMVm5yISp KuY5i72g==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wd0sS-0000000BPVx-119q; Fri, 26 Jun 2026 07:21:28 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 37666300BDE; Fri, 26 Jun 2026 09:21:28 +0200 (CEST) Date: Fri, 26 Jun 2026 09:21:28 +0200 From: Peter Zijlstra To: Vincent Guittot Cc: mingo@redhat.com, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, kprateek.nayak@amd.com, linux-kernel@vger.kernel.org, qyousef@layalina.io Subject: Re: [PATCH 3/6 v3] sched/eevdf: Update slice protection even when resched is already set Message-ID: <20260626072128.GI1181229@noisy.programming.kicks-ass.net> References: <20260624151229.1710703-1-vincent.guittot@linaro.org> <20260624151229.1710703-4-vincent.guittot@linaro.org> 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: <20260624151229.1710703-4-vincent.guittot@linaro.org> On Wed, Jun 24, 2026 at 05:12:26PM +0200, Vincent Guittot wrote: > Even if resched is already set, we might want to update or even cancel > the slice protection and ensure that the newly waking task will be the > next one to run. > > Signed-off-by: Vincent Guittot > Tested-by: K Prateek Nayak > --- > kernel/sched/fair.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 8639086e5d9e..854f3a9f1d80 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -9804,7 +9804,7 @@ static void wakeup_preempt_fair(struct rq *rq, struct task_struct *p, int wake_f > * prevents us from potentially nominating it as a false LAST_BUDDY > * below. > */ > - if (test_tsk_need_resched(rq->curr)) > + if (!sched_feat(PREEMPT_SHORT) && test_tsk_need_resched(rq->curr)) > return; > > if (!sched_feat(WAKEUP_PREEMPTION)) This one is leading to boot splats for me -- let me try and figure out why.