From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754249Ab0KHNik (ORCPT ); Mon, 8 Nov 2010 08:38:40 -0500 Received: from mx1.redhat.com ([209.132.183.28]:7082 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753870Ab0KHNij (ORCPT ); Mon, 8 Nov 2010 08:38:39 -0500 Date: Mon, 8 Nov 2010 08:37:45 -0500 From: Don Zickus To: Andrew Morton Cc: Sergey Senozhatsky , fweisbec@gmail.com, Peter Zijlstra , Ingo Molnar , LKML Subject: Re: [PATCH] watchdog: touch_nmi_watchdog should only touch local cpu not every one Message-ID: <20101108133745.GJ4823@redhat.com> References: <1288919932-1857-1-git-send-email-dzickus@redhat.com> <20101105135117.GA27712@swordfish.minsk.epam.com> <20101105125855.20e5ce4c.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101105125855.20e5ce4c.akpm@linux-foundation.org> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 05, 2010 at 12:58:55PM -0700, Andrew Morton wrote: > On Fri, 5 Nov 2010 15:51:18 +0200 > Sergey Senozhatsky wrote: > > > On (11/04/10 21:18), Don Zickus wrote: > > > void touch_nmi_watchdog(void) > > > { > > > + /* > > > + * Using __raw here because some code paths have > > > + * preemption enabled. If preemption is enabled > > > + * then interrupts should be enabled too, in which > > > + * case we shouldn't have to worry about the watchdog > > > + * going off. > > > + */ > > > + __raw_get_cpu_var(watchdog_nmi_touch) = true; > > > + > > > + touch_softlockup_watchdog(); > > > +} > > > +EXPORT_SYMBOL(touch_nmi_watchdog); > > > + > > > +void touch_all_nmi_watchdogs(void) > > > +{ > > > if (watchdog_enabled) { > > > unsigned cpu; > > > > > > @@ -151,7 +166,7 @@ void touch_nmi_watchdog(void) > > > } > > > touch_softlockup_watchdog(); > > > } > > > -EXPORT_SYMBOL(touch_nmi_watchdog); > > > +EXPORT_SYMBOL(touch_all_nmi_watchdogs); > > > > > > > Hello, > > Seems like no one is actually calling touch_all_nmi_watchdogs, as for now. > > Right? > > Yes, there doesn't seem a lot of point in adding the interface unless > we have callers. Yeah I wasn't sure how to deal with that. It didn't seem like any of the callers was relying on the fact that touch_nmi_watchdog() touched everyone. I just provided it as an option in case I misread someone's use of the touch_nmi_watchdog. I'll repost and remove it then. Thanks for the feedback. Cheers, Don