From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758701AbYG1WuV (ORCPT ); Mon, 28 Jul 2008 18:50:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751431AbYG1WuJ (ORCPT ); Mon, 28 Jul 2008 18:50:09 -0400 Received: from gw.goop.org ([64.81.55.164]:58371 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751307AbYG1WuI (ORCPT ); Mon, 28 Jul 2008 18:50:08 -0400 Message-ID: <488E4D1C.8000906@goop.org> Date: Mon, 28 Jul 2008 15:50:04 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: David Miller CC: mingo@elte.hu, peterz@infradead.org, linux-kernel@vger.kernel.org, Rusty Russell Subject: Re: combinatorial explosion in lockdep References: <20080728.153702.103032029.davem@davemloft.net> In-Reply-To: <20080728.153702.103032029.davem@davemloft.net> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org David Miller wrote: > The triggering event seems to be kstopmachine as done by the first > module load. This seems to create the situation where we do double RQ > locking on essentially all the run queues, in order to move the > kstopmachine threads around to their proprer cpus. I think this is > what starts to make the lockdep dependency chains huge. > Does Rusty's stop_machine rewrite which puts the threads on the correct cpus to start with at least mitigate the symptoms? J