From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266366AbUHBK4t (ORCPT ); Mon, 2 Aug 2004 06:56:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266453AbUHBK4t (ORCPT ); Mon, 2 Aug 2004 06:56:49 -0400 Received: from holomorphy.com ([207.189.100.168]:36523 "EHLO holomorphy.com") by vger.kernel.org with ESMTP id S266366AbUHBK4r (ORCPT ); Mon, 2 Aug 2004 06:56:47 -0400 Date: Mon, 2 Aug 2004 03:56:44 -0700 From: William Lee Irwin III To: Ingo Molnar Cc: Lee Revell , linux-kernel Subject: Re: [patch] preempt-timing-on-2.6.8-rc2-O2 Message-ID: <20040802105644.GD2334@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Ingo Molnar , Lee Revell , linux-kernel References: <1091403477.862.4.camel@mindpipe> <1091407585.862.40.camel@mindpipe> <20040802073938.GA8332@elte.hu> <1091435237.3024.9.camel@mindpipe> <20040802092855.GA15894@elte.hu> <20040802100815.GA18349@elte.hu> <20040802101840.GB2334@holomorphy.com> <20040802103516.GA20584@elte.hu> <20040802105100.GA22855@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040802105100.GA22855@elte.hu> User-Agent: Mutt/1.5.6+20040523i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Ingo Molnar wrote: >> (kjournald/189): 997us non-preemptible critical section violated 100 us >> preempt threshold starting at journal_commit_transaction+0x642/0x2b10 >> and ending at journal_commit_transaction+0x24ce/0x2b10 >> [] dump_stack+0x1e/0x30 >> [] dec_preempt_count+0x3f/0x50 >> [] journal_commit_transaction+0x24ce/0x2b10 >> [] kjournald+0x1a4/0x710 >> [] kernel_thread_helper+0x5/0x10 On Mon, Aug 02, 2004 at 12:51:00PM +0200, Ingo Molnar wrote: > ok, found it - it's a false positive in commit.c due to need_resched() > not doing a touch_preempt_timing(). Newest patch at: > http://redhat.com/~mingo/voluntary-preempt/preempt-timing-on-2.6.8-rc2-O2 Great, thanks for fixing this up. On Mon, Aug 02, 2004 at 12:51:00PM +0200, Ingo Molnar wrote: > i changed need_resched() to do a touch_preempt_timing() - this also got > rid of some other changes. All code i checked really takes > need_resched() seriously if it looks at it - any reason why you didnt > add this to need_resched() before? I was less sure of this as I hadn't audited need_resched() callers to be sure they did cond_resched() or similar. As you've carried out the audit of need_resched() callers, you have the certainty I didn't. -- wli