Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262042AbVBBHGq (ORCPT ); Wed, 2 Feb 2005 02:06:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262171AbVBBHGp (ORCPT ); Wed, 2 Feb 2005 02:06:45 -0500 Received: from mx1.elte.hu ([157.181.1.137]:21475 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S262042AbVBBHG0 (ORCPT ); Wed, 2 Feb 2005 02:06:26 -0500 Date: Wed, 2 Feb 2005 08:06:03 +0100 From: Ingo Molnar To: Lee Revell Cc: Tom Rini , Bill Huey , linux-kernel@vger.kernel.org, Rui Nuno Capela , Mark_H_Johnson@Raytheon.com, "K.R. Foley" , Adam Heath , Florian Schmidt , Thomas Gleixner , Fernando Pablo Lopez-Lezcano , Steven Rostedt Subject: Re: [patch] Real-Time Preemption, -RT-2.6.11-rc2-V0.7.36-04 Message-ID: <20050202070603.GA11605@elte.hu> References: <20041214132834.GA32390@elte.hu> <20050104064013.GA19528@nietzsche.lynx.com> <20050104094518.GA13868@elte.hu> <20050107192651.GG5259@smtp.west.cox.net> <20050126080952.GC4771@elte.hu> <1107288076.18349.7.camel@krustophenia.net> <20050201201704.GA32139@elte.hu> <1107289878.18349.20.camel@krustophenia.net> <20050201204359.GA346@elte.hu> <1107301515.27870.29.camel@krustophenia.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1107301515.27870.29.camel@krustophenia.net> User-Agent: Mutt/1.4.1i X-ELTE-SpamVersion: MailScanner 4.31.6-itk1 (ELTE 1.2) SpamAssassin 2.63 ClamAV 0.73 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1269 Lines: 42 * Lee Revell wrote: > OK. Rereading my old mail, it looks like there were some possibly > unresolved false positives with the userspace atomicity debugger. > > Here's one I get from alsaplayer. Would more information be required > to know if this is a false positive? this is a false positive that only triggers if PREEMPT_RT is disabled. Does the patch below fix it? (i've also updated the -37-03 patch that includes it.) Ingo --- linux/lib/rwsem.c.orig +++ linux/lib/rwsem.c @@ -169,6 +169,8 @@ rwsem_down_failed_common(struct rw_semap /* wait to be given the lock */ for (;;) { + unsigned long nosched_flag = current->flags & PF_NOSCHED; + if ((sleep_state == TASK_INTERRUPTIBLE) && signal_pending(current)) { spin_lock(&sem->wait_lock); @@ -181,7 +183,10 @@ rwsem_down_failed_common(struct rw_semap } if (!waiter->task) break; + + current->flags &= ~PF_NOSCHED; schedule(); + current->flags |= nosched_flag; set_task_state(tsk, sleep_state); } - 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/