From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: Run-time PM idea (was: Re: [RFC][PATCH 0/2] PM: Rearrange core suspend code) Date: Mon, 8 Jun 2009 14:11:59 +0100 Message-ID: <20090608131159.GA15100__27207.9079565176$1244466886$gmane$org@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-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20090608130509.GA3272@elte.hu> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Ingo Molnar Cc: LKML , ACPI Devel Maling List , pm list List-Id: linux-pm@vger.kernel.org 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