From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751663AbXC1NgM (ORCPT ); Wed, 28 Mar 2007 09:36:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751672AbXC1NgM (ORCPT ); Wed, 28 Mar 2007 09:36:12 -0400 Received: from mx1.redhat.com ([66.187.233.31]:39956 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751630AbXC1NgH (ORCPT ); Wed, 28 Mar 2007 09:36:07 -0400 Message-ID: <460A6EC0.4020701@redhat.com> Date: Wed, 28 Mar 2007 09:33:52 -0400 From: Prarit Bhargava User-Agent: Thunderbird 1.5.0.10 (X11/20070221) MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: Ingo Molnar , Linux Kernel , virtualization@lists.osdl.org, Eric Dumazet , Andrew Morton , Chris Lalancette , John Hawkes Subject: Re: [patch 3/4] Locally disable the softlockup watchdog rather than touching it References: <20070327214919.800272641@goop.org> <20070327215828.085422178@goop.org> In-Reply-To: <20070327215828.085422178@goop.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Fitzhardinge wrote: > > I haven't really worked out how this should interact with the nmi > watchdog; touch_nmi_watchdog() still ends up calling > touch_softlockup_watchdog(), so there's still some redundancy here. > > touch_nmi_watchdog is attempting to tickle _all_ CPUs softlockup watchdogs. Currently, the code is incorrect -- it is calling touch_softlockup_watchdog which touches only the current CPU's softlockup watchdog. I don't like the idea of having touch_softlockup_watchdog exported with your new code -- we still have two methods of effecting the softlockup watchdog and that's confusing and its going to cause serious problems down the road. The nmi watchdog code seems fine with just touching the CPU's nmi watchdogs. Is there a reason that you're pushing the enable/disable? All the cases called out seem to be just fine with calls to either effect that CPU's softlockup watchdog or doing all CPU's softlockup watchdogs. I'm not sure I see the benefit of complicating the softlockup watchdog code with this ... I agree with the first patch of this set -- it makes sense. But beyond that I'm not convinced the rest of the code is needed ... IMO. P.