Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755090AbZFHNMf (ORCPT ); Mon, 8 Jun 2009 09:12:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754123AbZFHNM0 (ORCPT ); Mon, 8 Jun 2009 09:12:26 -0400 Received: from cavan.codon.org.uk ([93.93.128.6]:52494 "EHLO vavatch.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753419AbZFHNMZ (ORCPT ); Mon, 8 Jun 2009 09:12:25 -0400 Date: Mon, 8 Jun 2009 14:11:59 +0100 From: Matthew Garrett To: Ingo Molnar Cc: "Rafael J. Wysocki" , Alan Stern , pm list , ACPI Devel Maling List , LKML , Magnus Damm Subject: Re: Run-time PM idea (was: Re: [linux-pm] [RFC][PATCH 0/2] PM: Rearrange core suspend code) Message-ID: <20090608131159.GA15100@srcf.ucam.org> References: <200906072347.00580.rjw@sisk.pl> <20090608065419.GA13568@elte.hu> <200906081330.50045.rjw@sisk.pl> <20090608130509.GA3272@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090608130509.GA3272@elte.hu> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: mjg59@codon.org.uk X-SA-Exim-Scanned: No (on vavatch.codon.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1290 Lines: 27 On Mon, Jun 08, 2009 at 03:05:09PM +0200, Ingo Molnar wrote: > > * Rafael J. Wysocki wrote: > > Well, we've been discussing it for quite a while and since more > > and more people are interested, I'm giving it a high priority. > > Cool. I think that if within a few years we could achieve that every > default distro (both on desktops and on servers) triggers PM > functionality runtime on common hardware, we'd both have lower power > consumption in general, and we'd have more robust suspend-resume > code as well. The difficulty is in determining when it's viable to autosuspend a given device. There's a limit to how much we can determine purely from kernel state (for instance, we could suspend ahci when there's no pending disk access, but we'd lose hotplug notifications) so there's going to have to be some level of userspace policy determination. Having the infrastructure in the kernel is an important part of this, but there'll be some distance to go after that. -- Matthew Garrett | mjg59@srcf.ucam.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/