From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754520Ab2HXH0x (ORCPT ); Fri, 24 Aug 2012 03:26:53 -0400 Received: from mailout-de.gmx.net ([213.165.64.22]:58254 "HELO mailout-de.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752611Ab2HXH0N (ORCPT ); Fri, 24 Aug 2012 03:26:13 -0400 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX1+JTkk8zp+JJgg1b277iWijPAwxt9cOkuSSKrwX5T xRAbtYq2TvDLNu Message-ID: <1345793168.4331.64.camel@marge.simpson.net> Subject: Re: [next-20120823] NOHZ: local_softirq_pending 200 on s/r From: Mike Galbraith To: sedat.dilek@gmail.com Cc: Paul McKenney , Paul McKenney , LKML , Thomas Gleixner , x86@kernel.org, linux-next Date: Fri, 24 Aug 2012 09:26:08 +0200 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2012-08-23 at 12:04 +0200, Sedat Dilek wrote: > Jack Winter confirmed to see similiar NOHZ messages also on > v3.4.9-rt17 kernel (CPU: Core2Duo when no suspend performed): > > [15223.171585] NOHZ: local_softirq_pending 08 These can be caused by blocking while holding local_softirq_lock. Even with per softirq threads, and then (yet more overhead) splitting the lock to make sure one softirq type can't block another, _and_ only griping if the lock for the pending softirq is _not_ held, seems the little bugger can still be triggered very rarely by syn flood induced handler bail/raise. Annoying little gripe :) -Mike