From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755963AbXGIPxX (ORCPT ); Mon, 9 Jul 2007 11:53:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754545AbXGIPw5 (ORCPT ); Mon, 9 Jul 2007 11:52:57 -0400 Received: from andromeda.dapyr.net ([69.45.6.100]:37397 "EHLO andromeda.dapyr.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754328AbXGIPw4 (ORCPT ); Mon, 9 Jul 2007 11:52:56 -0400 From: darnok@68k.org Date: Mon, 9 Jul 2007 11:53:02 -0400 To: linux-kernel@vger.kernel.org Subject: Re: [PATCH] Inhibit NMI watchdog when Alt-SysRq-T operation is underway. Message-ID: <20070709155302.GB26570@andromeda.dapyr.net> References: <20070709140242.GA18098@andromeda.dapyr.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070709140242.GA18098@andromeda.dapyr.net> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 09, 2007 at 10:02:42AM -0400, Konrad Rzeszutek wrote: > On large memory configuration with not so fast CPUs the NMI watchdog > is triggered when memory addresses are being gathered and printed. > The code paths for Alt-SysRq-t are sprinkled with touch_nmi_watchdog > in various places but not in this routine (or in the loop that utilizes > this function). The patch has been tested for regression on large CPU+memory > configuration (128 logical CPUs + 224 GB) and 1,2,4,16-CPU sockets with various > memory sizes (1,2,4,6,20). And the patch: diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index aac1c0b..b6e7d67 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -330,6 +330,10 @@ static int print_trace_stack(void *data, static void print_trace_address(void *data, unsigned long addr) { + static int i = 0; + if (i && ((i % 8) == 0)) + touch_nmi_watchdog(); + i++; printk_address(addr); }