From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: [linux-pm] [PATCH 0/8] Suspend block api (version 8) Date: Thu, 27 May 2010 22:36:35 +0100 Message-ID: <20100527213635.GA9916@srcf.ucam.org> References: <20100527155201.GA31937@srcf.ucam.org> <20100527171615.15a1fd3d@lxorguk.ukuu.org.uk> <20100527161943.GA32764@srcf.ucam.org> <20100527170740.GA1980@srcf.ucam.org> <1274980391.27810.5552.camel@twins> <20100527171644.GA2468@srcf.ucam.org> <1274980856.27810.5582.camel@twins> <20100527172510.GC2468@srcf.ucam.org> <20100527223751.7af3b5ee@lxorguk.ukuu.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20100527223751.7af3b5ee@lxorguk.ukuu.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Alan Cox Cc: Peter Zijlstra , Thomas Gleixner , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Florian Mickler , Vitaly Wool , LKML , Paul@smtp1.linux-foundation.org, felipe.balbi@nokia.com, Linux OMAP Mailing List , Linux PM List-Id: linux-omap@vger.kernel.org On Thu, May 27, 2010 at 10:37:51PM +0100, Alan Cox wrote: > On Thu, 27 May 2010 18:25:10 +0100 > Matthew Garrett wrote: > > How (and why) does the WoL (which may be *any* packet, not just a magic > > one) turn the screen back on? > > Well on my laptop today it works like this > > A WoL packet arrives > The CPU resumes > Depp process, chipset and laptop BIOS magic happens > The kernel gets called > The kernel lets interested people know a resume occurred No it doesn't. The kernel continues executing anything that was on the runqueue before the scheduler stopped. If you're using idle-based suspend then there's nothing on the runqueue - the application that should be scheduled because of the event is blocked on writing to the screen. -- Matthew Garrett | mjg59@srcf.ucam.org