From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756404AbYB2DeV (ORCPT ); Thu, 28 Feb 2008 22:34:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753977AbYB2DeK (ORCPT ); Thu, 28 Feb 2008 22:34:10 -0500 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:45344 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751381AbYB2DeJ (ORCPT ); Thu, 28 Feb 2008 22:34:09 -0500 Date: Thu, 28 Feb 2008 21:34:02 -0600 From: Paul Jackson To: David Rientjes Cc: mingo@elte.hu, a.p.zijlstra@chello.nl, tglx@linutronix.de, oleg@tv-sign.ru, rostedt@goodmis.org, maxk@qualcomm.com, linux-kernel@vger.kernel.org Subject: Re: [RFC/PATCH 0/4] CPUSET driven CPU isolation Message-Id: <20080228213402.7260906f.pj@sgi.com> In-Reply-To: References: <20080227222103.673194000@chello.nl> <20080228075010.GA28781@elte.hu> <20080228020808.3fd22f77.pj@sgi.com> <20080228090847.GA1133@elte.hu> <20080228031710.3405e405.pj@sgi.com> <20080228113728.7b8e5811.pj@sgi.com> <20080228164637.114fb19d.pj@sgi.com> <20080228181611.49671331.pj@sgi.com> Organization: SGI X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.12.0; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org David, responding to pj, responding to ...: > > > > Move the watchdog/0 thread to a cpuset that doesn't have access to cpu 0. > > > > I still don't understand ... you must have some context in mind that > > I've spaced out ... I can't even tell if that is a statement or a > > question. > > > > You said that you weren't aware of any problems that could arise that are > fixed with this added check in set_cpus_allowed(), Ok, now I understand your question - thanks. I think your question arises from misreading what I wrote. I did not say that I wasn't "aware of any problems that could arise" I did say, as you quoted, from Thu, 28 Feb 2008 11:37:28 -0600: > > I don't have strong opinions either way on this patch; it adds an error > check that makes sense. I haven't seen much problem not having this check, > nor do I know of any code that depends on doing what this check prohibits. - This does not say no (none whatsoever) problem could (ever in the future) arise. - This does say not much (just a little) problem had arisen (so far in the past). Apparently, you thought I was trying to reject the patch on the grounds that no such problem could ever occur, and you were showing how such a problem could occur. I wasn't trying to reject the patch, and I agree that the check made sense, and I agree that such a problem could occur, as your example shows. -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.940.382.4214