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 AED501E3DDE for ; Fri, 26 Jun 2026 07:55:04 +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=1782460505; cv=none; b=BPbjVP9QYaU78PXnrs0Nkna5aBmU4aSlhgFtUNIOpfDxaTb98YPXg7KEDqtrDcc+44OoPnqzaLS8OyouOBSG4GrQAOpsedbAOtkhHqxYdnvyjUq2SizYo/RgbzgYvEEDnyOZcRinp7D0tkl2WQSFZBCoC8D9Dw4+glLZaxxDQ14= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782460505; c=relaxed/simple; bh=AhEoZPa1ubjGCrnYln+yNvo5fGjGq4BKTXQIvMquWAY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=YnL1i2GBJTBeAVSpb+k1Ljf0mmuwR76AVjSPBKDsG5sDOnGeajiDB+daCTpwe8AW5HIHxoWOXxIY4nQX48sZrTfYXCpLkFuk/2Vo6/gRDbD/gVI95dukzuS7JB+8uRldB5Na3aiuX9B9xfQg9UDu6ZAGBtiT1oEGmGqmNc4VsgQ= 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=mYNsFUpr; 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="mYNsFUpr" 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=eRPyzc7EDdDL/lNOR607b5EPROgL6TOgJre79qOm51Q=; b=mYNsFUprxdR91zIYGCsEloJjyf /LL6n9xSlOOFElUkN3hBIisZ5XYsYM4MsBUqfbSnxkNi2RNugNyd2JZGNtOgvzzvJR0G8nw0o+11j g42gNrp6UaCyY4tAtagzSBQm7MddQTtNg0IpWzjO6AJYwbKaRg54APSg7viPjan62gbve8igTMwP2 Q4cxj5Cm5vKBUL+xulMorDSfrAaBHCJvv+hQAx1TTsJAuSVV0H73ghcqdT1eIIrIQyahhDyy1LLJd 7NoXsewjaQyUay7L6QIlU3ap8dDBco2K/q/akNxmZkKukZ1Jhq49DBuBQZhA4QoHX0AQ/PZdsv9tj YUO1zsPA==; 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 1wd1Or-0000000BSJh-0VjV; Fri, 26 Jun 2026 07:54:57 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id A4590300BDE; Fri, 26 Jun 2026 09:54:56 +0200 (CEST) Date: Fri, 26 Jun 2026 09:54:56 +0200 From: Peter Zijlstra To: Vincent Guittot Cc: K Prateek Nayak , mingo@redhat.com, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, linux-kernel@vger.kernel.org, qyousef@layalina.io Subject: Re: [PATCH 6/6 v3] sched/eevdf: Speedup short slice task scheduling Message-ID: <20260626075456.GC2568396@noisy.programming.kicks-ass.net> References: <20260624151229.1710703-7-vincent.guittot@linaro.org> <613c1bde-4152-493f-b103-f1fda035b4af@amd.com> <20260625083720.GR42921@noisy.programming.kicks-ass.net> <20260625100957.GA2568396@noisy.programming.kicks-ass.net> <20260625222843.GE1181229@noisy.programming.kicks-ass.net> <9a7608a5-d164-4b1c-93d9-6a7431b7a896@amd.com> <20260626071832.GH1181229@noisy.programming.kicks-ass.net> 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: <20260626071832.GH1181229@noisy.programming.kicks-ass.net> On Fri, Jun 26, 2026 at 09:18:32AM +0200, Peter Zijlstra wrote: > On Fri, Jun 26, 2026 at 09:05:29AM +0200, Vincent Guittot wrote: > > On Fri, 26 Jun 2026 at 05:57, K Prateek Nayak wrote: > > > > > > Hello Peter, > > > > > > On 6/26/2026 3:58 AM, Peter Zijlstra wrote: > > > > +static u64 ineligible_vruntime(struct cfs_rq *cfs_rq) > > > > +{ > > > > + struct sched_entity *curr = cfs_rq->curr; > > > > + long weight = cfs_rq->sum_weight; > > > > + s64 delta = 0; > > > > + > > > > + if (curr && !curr->on_rq) > > > > + curr = NULL; > > > > + > > > > + /* > > > > + * This is called from set_next_task_fair(.first=true) / > > > > + * set_protect_slice() so curr had better be set and on_rq. > > > > + */ > > > > + WARN_ON_ONCE(!curr); > > > > > > set_protect_slice() is indeed called from set_next_entity(.first=true) > > > but it is done after __dequeue_entity() and before "cfs_rq->curr" is > > > set (both sched/flat and sched/core have the same pattern). > > > > Yes, I confirm that set_protect_slice() is called before setting curr > > in tip/sched/core but I think that Peter added flat hierarchy patches > > in his tree > > Indeed I did; I was planning to stick them in this cycle, so I figure I > should be doing these patches on top. I pushed out the now booting pile of gunk into queue:sched/core. I've made some rando edits to your (Vincent's) patches, if you disagree or want changes, let me know. This really is just my quilt stack of the moment for sched/core and it can easily be changed. /me wonders how the fuck it can be 28C before 10am and goes in search of more water.