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 6003727E054 for ; Fri, 23 Jan 2026 21:31:49 +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=1769203912; cv=none; b=qwUK0snjDr0dRHIDFA+dVGvF3Tljox4H21Bnas6cNPRngwsKIlkHHjAkfmGHEh8nlCQfIHmEjTdRtFWQXi7NXZfpNMuJ/iy+9GJqDVOnqsj6tU7jwqy43Ch3LMDyWi6D3dzoo0BaaGi4LYDiYP7nYFJE9QxTX3sCX/6wmXQ1SwQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769203912; c=relaxed/simple; bh=Q2R/zTKwros3myCz7TjJp6fLL7u052NHB7Cjv7Bhmlo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cQ/JgzVO8PtA2lbInbfGW0mjswlPynyv0onWMBRXYtcV7OnS3ct3oKTGA4liuDjMcPyV6AsT5mLZsmk9yDcKaq+PE3QBwZR/ZiWiS6pRCuy5JaIQwIg1TU2TaJrfcIvRyFiylNW6Biw2YaSPnJE0ASk990tn3z9oQQdfvhedSdM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=ql9KDRqu; 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=none 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="ql9KDRqu" 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=9fYsxqt5Y1gRRf8gSeXYgf9a6HYcdyZVZpRiCCLJ8Hc=; b=ql9KDRquBXcbifbLjOHhkI5+Tk QIwv2FHy3MQuyxtbVuc1xBfUxeDLMXLA6H7rUBAJR3ZyAu2W96AWY1q40k8SttclA67l8CELp7gkg AbFXLd1Pdi4DOLBoUWML3jvJ9pjDpriY81RxKQFOz+IxNDtbETsnQmnoGFJA8N31VKC6ft8ML2WyI gYMuM6Bjh56ty4eF+JVUTV7YCGkHQre0hNVkjh0hBI3KM+pQAXFngkHPZKGMmigC1pGwku8Q8eICx rU/m517muSvs/sT94erOO08wiQRrGkgEAgReCOdbLVQIGLNYWNIxNUsjypEOEtAjngGNbM/TV8Xaz 408Qqc7w==; 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 4.98.2 #2 (Red Hat Linux)) id 1vjOkn-00000002JIA-3z05; Fri, 23 Jan 2026 21:31:42 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id E04693007E1; Fri, 23 Jan 2026 22:31:40 +0100 (CET) Date: Fri, 23 Jan 2026 22:31:40 +0100 From: Peter Zijlstra To: K Prateek Nayak Cc: Vincent Guittot , "wangtao (EQ)" , mingo@redhat.com, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, tanghui20@huawei.com, zhangqiao22@huawei.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] sched/eevdf: Update se->vprot in reweight_entity() Message-ID: <20260123213140.GB3268448@noisy.programming.kicks-ass.net> References: <20260120123113.3518950-1-wangtao554@huawei.com> <8e7aadf8-b7a0-4500-ad2d-507665007694@amd.com> <15d8374f-b1a5-4946-829d-8e9c6ef39272@huawei.com> <20260123153854.GU166857@noisy.programming.kicks-ass.net> <44c45e82-25e7-4d70-a46d-fb34e6aacbd6@amd.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: <44c45e82-25e7-4d70-a46d-fb34e6aacbd6@amd.com> On Fri, Jan 23, 2026 at 10:09:05PM +0530, K Prateek Nayak wrote: > > @@ -3823,6 +3830,8 @@ static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, > > enqueue_load_avg(cfs_rq, se); > > if (se->on_rq) { > > place_entity(cfs_rq, se, 0); > > + if (vprot) > > + se->vprot = se->vruntime + vprot; > > Scaling vprot makes sense too. Can there be a problem where "vprot" > turns to zero on scaling (weight > (vprot * se->load.weight)) but we > don't end up updating "se->vprot"? Yeah, this can happen, but in that case the thing is 'small'. I'll see if I can fix it though. > Since we are looking at these bits, can you also please take a look at > https://lore.kernel.org/lkml/20251226001731.3730586-1-quzicheng@huawei.com/ > which I feel might be a genuine issue when we are reweight the curr's > vruntime. Oh, I hadn't found that yet -- people should know better than to send mail during x-mas ;-)