From mboxrd@z Thu Jan 1 00:00:00 1970 From: Uli Luckas Subject: Re: [PATCH 01/13] PM: Add wake lock api. Date: Fri, 13 Feb 2009 19:13:52 +0100 Message-ID: <200902131913.54154.u.luckas@road.de> References: <1233802226-23386-1-git-send-email-arve@android.com> <200902131746.42914.u.luckas@road.de> <20090213170518.GA29902@srcf.ucam.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090213170518.GA29902@srcf.ucam.org> Content-Disposition: inline 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: Matthew Garrett Cc: Brian Swetland , linux-pm@lists.linux-foundation.org, "ncunningham@crca.org.au" List-Id: linux-pm@vger.kernel.org On Friday, 13. February 2009, Matthew Garrett wrote: > On Fri, Feb 13, 2009 at 05:46:42PM +0100, Uli Luckas wrote: > > That's racy. By the time the daemon notices that a process crashed, the > > kernel might already have triggered suspend. userspace might then be > > frozen before it can accuire the 'process restarting' lock. > > I also wonder, if it is immanently racy to use userspcae communication > > (client/daemon) for suspend locks. What if the daemon is already frozen > > when a client sends a lock request request? > > The daemon holds the lock in the first place. When did the daemon take the lock? When it anticipated the process would crash? > There's no race. As for issues with the freezer, I think my position on that > is fairly well known... Not to me. Uli -- ------- ROAD ...the handyPC Company - - - ) ) ) Uli Luckas Head of Software Development ROAD GmbH Bennigsenstr. 14 | 12159 Berlin | Germany fon: +49 (30) 230069 - 62 | fax: +49 (30) 230069 - 69 url: www.road.de Amtsgericht Charlottenburg: HRB 96688 B Managing director: Hans-Peter Constien