Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754093AbZJBBXg (ORCPT ); Thu, 1 Oct 2009 21:23:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754058AbZJBBXf (ORCPT ); Thu, 1 Oct 2009 21:23:35 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:60167 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754052AbZJBBXf (ORCPT ); Thu, 1 Oct 2009 21:23:35 -0400 Date: Thu, 1 Oct 2009 18:21:50 -0700 (PDT) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Theodore Tso , Martin Schwidefsky , John Stultz cc: "Rafael J. Wysocki" , tglx@linutronix.de, Linux Kernel Mailing List , Ondrej Zary , Magnus Damm Subject: Re: T400 suspend/resume regression -- bisected to a mystery merge commit In-Reply-To: <20091002005907.GA7490@mit.edu> Message-ID: References: <200909271813.42829.rjw@sisk.pl> <20090928135109.GB17514@mit.edu> <200909282322.57824.rjw@sisk.pl> <20091002005907.GA7490@mit.edu> User-Agent: Alpine 2.01 (LFD 1184 2008-12-16) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1355 Lines: 36 On Thu, 1 Oct 2009, Theodore Tso wrote: > > commit 8c3ee48dabee782d470cc4c7048ea64bb8b7d1cb > Author: Theodore Ts'o > Date: Thu Oct 1 20:39:03 2009 -0400 > > Revert "timekeeping: Update clocksource with stop_machine" > > This reverts commit 75c5158f70c065b9704b924503d96e8297838f79. Hmm. Looks good. But you didn't cc most of the people actually involved with that commit (Martin who is the author, and John who acked it). I think the revert is the right thing to do, especially as that 'clocksource_mutex' looks totally bogus. Either the thing is protected by 'stop_machine' or it's not. In neither case does it seem to make any sense to replace a spinlock with a mutex. And resuming anything with a big mutex is crazy anyway. That said, I do wonder if this is already fixed. See commit 89133f93508137231251543d1732da638e6022e1: clocksource: Resume clocksource without taking the clocksource mutex which already undid the part that probably mattered for you. That said, I still do think that that mutex is dubious, so maybe we should undo it all. Linus -- 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/