Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756590AbXERM4Q (ORCPT ); Fri, 18 May 2007 08:56:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754443AbXERM4I (ORCPT ); Fri, 18 May 2007 08:56:08 -0400 Received: from www.osadl.org ([213.239.205.134]:38758 "EHLO mail.tglx.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754335AbXERM4H (ORCPT ); Fri, 18 May 2007 08:56:07 -0400 Subject: Re: [BUG] local_softirq_pending storm From: Thomas Gleixner To: Anant Nitya Cc: linux-kernel@vger.kernel.org In-Reply-To: <200705171211.23350.kernel@prachanda.hub> References: <200705091942.22920.kernel@prachanda.hub> <1178834326.22481.18.camel@localhost.localdomain> <200705171211.23350.kernel@prachanda.hub> Content-Type: text/plain Date: Fri, 18 May 2007 15:01:17 +0200 Message-Id: <1179493277.12981.69.camel@chaos> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 (2.8.3-2.fc6) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1479 Lines: 39 On Thu, 2007-05-17 at 12:11 +0530, Anant Nitya wrote: > On Friday 11 May 2007 03:28:46 Thomas Gleixner wrote: > > > Ok, that's consistent with earlier reports. The problem surfaces when > > one of the SMT-"cpus" goes idle. The problem goes away when you disable > > hyperthreading. > Yes with HT disabled in BIOS there is no local_softirq_pending messages. BTW > why does this problem persist only with X ? No idea. I uploaded a debug patch against 2.6.22-rc1 to http://www.tglx.de/private/tglx/2.6.22-rc1-hrt-debug.patch Can you give it a try and report the output ? > > When you apply the ratelimit patch, does the softlockup problem > > persist ? > > > Yes, though softlockup is rare and mostly hit when system is under high load. > Apart of that I am also getting following messages consistently across > multiple boot cycles with NOHZ=y and ratelimit patch applied. > > May 15 11:51:22 rudra kernel: [ 2594.341068] Clocksource tsc unstable (delta = > 28111260302 ns) > May 15 11:51:22 rudra kernel: [ 2594.343194] Time: acpi_pm clocksource has > been installed. That's informal. The TSC is detected to be unstable and replaced by the pm timer. Nothing to worry about. It happens with NOHZ=n as well, right ? tglx - 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/