Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758760AbYCDRcK (ORCPT ); Tue, 4 Mar 2008 12:32:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751370AbYCDRb5 (ORCPT ); Tue, 4 Mar 2008 12:31:57 -0500 Received: from gateway.drzeus.cx ([85.8.24.16]:55980 "EHLO smtp.drzeus.cx" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751228AbYCDRb4 (ORCPT ); Tue, 4 Mar 2008 12:31:56 -0500 Date: Tue, 4 Mar 2008 18:30:32 +0100 From: Pierre Ossman To: Andi Kleen Cc: "Pallipadi, Venkatesh" , Dave Jones , Andi Kleen , Alan Stern , LKML , Adam Belay , Lee Revell , linux-pm@lists.linux-foundation.org, Pavel Machek Subject: Re: [linux-pm] [PATCH] cpuidle: avoid singing capacitors Message-ID: <20080304183032.17084e39@mjolnir.drzeus.cx> In-Reply-To: <20080304172918.GA27332@one.firstfloor.org> References: <924EFEDD5F540B4284297C4DC59F3DEEA2E8B2@orsmsx423.amr.corp.intel.com> <20080303231033.GB15255@one.firstfloor.org> <20080304040048.GA31562@codemonkey.org.uk> <20080304071423.0e6b71c1@mjolnir.drzeus.cx> <20080304181924.70aaf8c1@mjolnir.drzeus.cx> <20080304172918.GA27332@one.firstfloor.org> X-Mailer: Claws Mail 3.3.1 (GTK+ 2.12.8; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1209 Lines: 24 On Tue, 4 Mar 2008 18:29:18 +0100 Andi Kleen wrote: > > So for now, I'm back to thinking that measuring the interval between deep sleeps is the better approach. I could use some ideas for a good clock source though. I haven't dug much deeper than jiffies when it comes to kernel timekeeping. > > jiffies should work, you just need to make sure you measure them at the > right place. In particular there is some code in dyntick that catches > up on jiffies after the deep sleep when the normal timer handler didn't run > and jiffies are only usable again after that code executed. > And how can I tell if this handler has run? Not that it really matters I guess, as I don't think running it from the cpuidle governor is very sane. -- -- Pierre Ossman Linux kernel, MMC maintainer http://www.kernel.org PulseAudio, core developer http://pulseaudio.org rdesktop, core developer http://www.rdesktop.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/