Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763012AbXJES3U (ORCPT ); Fri, 5 Oct 2007 14:29:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753593AbXJES3K (ORCPT ); Fri, 5 Oct 2007 14:29:10 -0400 Received: from mga03.intel.com ([143.182.124.21]:53503 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751281AbXJES3I convert rfc822-to-8bit (ORCPT ); Fri, 5 Oct 2007 14:29:08 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.21,233,1188802800"; d="scan'208";a="229789551" X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: nmi_watchdog fix for x86_64 to be more like i386 Date: Thu, 4 Oct 2007 21:37:41 -0700 Message-ID: <653FFBB4508B9042B5D43DC9E18836F501797305@scsmsx415.amr.corp.intel.com> In-Reply-To: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: nmi_watchdog fix for x86_64 to be more like i386 Thread-Index: AcgEvS7xuZ/Z+t6UQHCQQzCYfj0NmwCIixbg References: <46FA4A800200006C000192FE@sinclair.provo.novell.com> <200710020007.09864.ak@suse.de> <200710020751.42994.ak@suse.de> From: "Pallipadi, Venkatesh" To: "Thomas Gleixner" , "Andi Kleen" Cc: "Arjan van de Ven" , "David Bahi" , "LKML" , , "Andrew Morton" , "Ingo Molnar" , "Gregory Haskins" X-OriginalArrivalTime: 05 Oct 2007 04:37:43.0003 (UTC) FILETIME=[78093AB0:01C80709] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1257 Lines: 41 >-----Original Message----- >From: linux-kernel-owner@vger.kernel.org >[mailto:linux-kernel-owner@vger.kernel.org] On Behalf Of >Thomas Gleixner >Sent: Monday, October 01, 2007 11:19 PM >To: Andi Kleen >Cc: Arjan van de Ven; David Bahi; LKML; >linux-rt-users@vger.kernel.org; Andrew Morton; Ingo Molnar; >Gregory Haskins >Subject: Re: nmi_watchdog fix for x86_64 to be more like i386 > >> >> The only workaround for chipsets ignoring IRQ affinity would >be to keep >> track on which CPU irq 0 happens and then restart APIC timer >interrupts >> on the others (or send IPIs) as needed. But that would be >fairly ugly. > >The clock events code does handle this already. The broadcast >interrupt >can come in on any cpu. It's just the nmi watchdog which would >be affected >by that. > Probably we can workaround this by keeping track of IRQ0 count at percpu level and use local apic timer + this percpu counter in NMI. Or just increment local apic timer count in IRQ0 with nohz enabled. Thanks, Venki - 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/