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 DD5D71DF66F for ; Fri, 2 Aug 2024 11:30:08 +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=1722598210; cv=none; b=WFvfKR/PjbWPbQEtKeNVCDFL4TWXTebCs3Nzw2ScyGcpzhbQ+YuvCNd0ntl3Zoph5KMMBszBA3/uMA/ucQ9nCGcscNQpMqMmsyMTQR4vJ0GYbE69t3Ftj3z+B/XBSz+1NVa77RF8ghwKE7FcyQJ0Arxofs73t3B/I4W7Klum42w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722598210; c=relaxed/simple; bh=QsooQlMyoqgdxE/Wr4zS68WyUzTUBfhULabxOdNdLS0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=NjLsEGHt91qfQGUyp/BaFlg3rePla+ReWQOnt01U/AjH18gjBn9U7FpNWnuXjfrIqhrLXMOE2uVqo1ApbQfdMZWqmaIJzPol0Alue1wOtqKZJdzUfTmY6HtAPfryd5O+paswP3MEODkj+0U1cukSF9GgB6Z8lkWNSayL1wlgVBQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (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=VyW0sRxP; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (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="VyW0sRxP" 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=yCEzN1RSmv0If3JnoPB9uROyFaA8GRSimv/i1r/C9fw=; b=VyW0sRxPosmuiT5mJvN7ApHSWW L8nDCSuWAhFUpsPqmhmyarLBA7oY381Bi7Q9azfFy6a6NJk5OiAZnTzi6a6+ntDDqyN+EHVtEXZTN ZzLNluDHWc6ypqeh7my/FTShNQ71T/GTDwOvvmMZz+HbA7NDqEkxREXU6AtDjDGfXvDeQ0QPUkinn 3uLHw1QYTueyCSZjgpRgfjiTqrsNgtyP7IypV73eMoylGQusL+h0vFBTDOQ/5eO3FYiGpxXREQdxk x/9n40p38JGVoE4I4KtGMSrdUWnc1ov8Fh7eaiKb1bMUX7CzMqh5yXUgdYZIHRc3wTwC4HZQ0dlyO 6/BCi9hw==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZqTq-00000000xgZ-2d55; Fri, 02 Aug 2024 11:29:54 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 6460630049D; Fri, 2 Aug 2024 13:29:53 +0200 (CEST) Date: Fri, 2 Aug 2024 13:29:53 +0200 From: Peter Zijlstra To: Juri Lelli Cc: mingo@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, linux-kernel@vger.kernel.org, kprateek.nayak@amd.com, wuyun.abel@bytedance.com, youssefesmat@chromium.org, tglx@linutronix.de, efault@gmx.de Subject: Re: [RFC PATCH 24/24] sched/time: Introduce CLOCK_THREAD_DVFS_ID Message-ID: <20240802112953.GJ39708@noisy.programming.kicks-ass.net> References: <20240727102732.960974693@infradead.org> <20240727105031.053611186@infradead.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: On Mon, Jul 29, 2024 at 09:53:17AM +0200, Juri Lelli wrote: > Hi Peter, > > On 27/07/24 12:27, Peter Zijlstra wrote: > > In order to measure thread time in a DVFS world, introduce > > CLOCK_THREAD_DVFS_ID -- a copy of CLOCK_THREAD_CPUTIME_ID that slows > > down with both DVFS scaling and CPU capacity. > > > > The clock does *NOT* support setting timers. > > > > Useful for both SCHED_DEADLINE and the newly introduced > > sched_attr::sched_runtime usage for SCHED_NORMAL. > > Just so I'm sure I understand, this would be useful for estimating the > runtime needs of a (also DEADLINE) task when DVFS is enabled, right? Correct, DVFS or biggie-smalls CPUs with mixed capacities.