Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757104AbZLKEKy (ORCPT ); Thu, 10 Dec 2009 23:10:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755846AbZLKEKx (ORCPT ); Thu, 10 Dec 2009 23:10:53 -0500 Received: from bld-mail14.adl6.internode.on.net ([150.101.137.99]:52469 "EHLO mail.internode.on.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755489AbZLKEKx (ORCPT ); Thu, 10 Dec 2009 23:10:53 -0500 Date: Fri, 11 Dec 2009 15:10:41 +1100 From: Dave Chinner To: Ingo Molnar Cc: "Rafael J. Wysocki" , Alan Stern , Linus Torvalds , Zhang Rui , LKML , ACPI Devel Maling List , pm list , Peter Zijlstra , Lachlan McIlroy Subject: Re: spinlock in completion_done() (was: Re: Async resume patch (was: Re: [GIT PULL] PM updates for 2.6.33)) Message-ID: <20091211041041.GJ30608@discord.disaster> References: <200912082248.14138.rjw@sisk.pl> <20091209092922.GC28428@elte.hu> <200912092337.52492.rjw@sisk.pl> <20091210075947.GD25549@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091210075947.GD25549@elte.hu> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1483 Lines: 36 On Thu, Dec 10, 2009 at 08:59:47AM +0100, Ingo Molnar wrote: > * Rafael J. Wysocki wrote: > > On Wednesday 09 December 2009, Ingo Molnar wrote: > > > * Rafael J. Wysocki wrote: > > > > On Tuesday 08 December 2009, Alan Stern wrote: > > > > > On Tue, 8 Dec 2009, Rafael J. Wysocki wrote: > > > > > > > > > > > BTW, is there a good reason why completion_done() doesn't use spin_lock_irqsave > > > > > > and spin_unlock_irqrestore? complete() and complete_all() use them, so why not > > > > > > here? > > > > > > > > > > And likewise in try_wait_for_completion(). It looks like a bug. Maybe > > > > > these routines were not intended to be called with interrupts disabled, > > > > > but that requirement doesn't seem to be documented. And it isn't a > > > > > natural requirement anyway. When I implemented them they were not called from anywhere that disabled interrupts. IIRC the main reason I used spin_lock_irq() was because that is what wait_for_completion() used at the time.... > > > that's a bug that should be fixed - all the wakeup side (and atomic) > > > variants of completetion API should be irq safe. I see no problems with that ;) Cheers, Dave. -- Dave Chinner david@fromorbit.com -- 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/