Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755989AbZLTSKA (ORCPT ); Sun, 20 Dec 2009 13:10:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755919AbZLTSJ5 (ORCPT ); Sun, 20 Dec 2009 13:09:57 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:37390 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755840AbZLTSJ5 (ORCPT ); Sun, 20 Dec 2009 13:09:57 -0500 From: "Rafael J. Wysocki" To: Alan Stern Subject: Re: Async suspend-resume patch w/ completions (was: Re: Async suspend-resume patch w/ rwsems) Date: Sun, 20 Dec 2009 19:10:26 +0100 User-Agent: KMail/1.12.3 (Linux/2.6.32-rjw; KDE/4.3.3; x86_64; ; ) Cc: Linus Torvalds , Dmitry Torokhov , Zhang Rui , LKML , ACPI Devel Maling List , pm list References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200912201910.26895.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1513 Lines: 34 On Sunday 20 December 2009, Alan Stern wrote: > On Sun, 20 Dec 2009, Rafael J. Wysocki wrote: > > > > It's too early to come to this sort of conclusion (i.e., that suspend > > > and resume react very differently to an asynchronous approach). Unless > > > you have some definite _reason_ for thinking that resume will benefit > > > more than suspend, you shouldn't try to generalize so much from tests > > > on only two systems. > > > > In fact I have one reason. Namely, the things that drivers do on suspend and > > resume are evidently quite different and on these two systems I was able to > > test they apparently took different amounts of time to complete. > > > > The very fact that on both systems resume is substantially longer than suspend, > > even if all devices are suspended and resumed synchronously, is quite > > interesting. > > Yes, it is. But it doesn't mean that suspend won't benefit from > asynchronicity; it just means that the benefits might not be as large > as they are for resume. Agreed, although that rises the question whether they are sufficiently significant. I guess time will tell. With the i8042 done asynchronously they are IMO. BTW, what's the right place to call device_enable_async_suspend() for USB devices? Rafael -- 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/