Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268080AbUJOPoj (ORCPT ); Fri, 15 Oct 2004 11:44:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268084AbUJOPoi (ORCPT ); Fri, 15 Oct 2004 11:44:38 -0400 Received: from mx1.elte.hu ([157.181.1.137]:32701 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S268080AbUJOPoZ (ORCPT ); Fri, 15 Oct 2004 11:44:25 -0400 Date: Fri, 15 Oct 2004 17:45:42 +0200 From: Ingo Molnar To: "Paul E. McKenney" Cc: Dipankar Sarma , Sven Dietrich , Daniel Walker , Andrew Morton , linux-kernel@vger.kernel.org, abatyrshin@ru.mvista.com, amakarov@ru.mvista.com, emints@ru.mvista.com, ext-rt-dev@mvista.com, hzhang@ch.mvista.com, yyang@ch.mvista.com, "Witold. Jaworski@Unibw-Muenchen. De" , arnd.heursch@unibw-muenchen.de Subject: Re: [ANNOUNCE] Linux 2.6 Real Time Kernel Message-ID: <20041015154542.GA8257@elte.hu> References: <20041011215420.GA19796@elte.hu> <20041012055029.GB1479@elte.hu> <20041014050905.GA6927@in.ibm.com> <20041014071810.GB9729@elte.hu> <20041015145915.GA1266@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20041015145915.GA1266@us.ibm.com> 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: 678 Lines: 17 * Paul E. McKenney wrote: > One caution (which you are no doubt already aware of) -- if an RCU > algorithm that reads (rcu_read_lock()/rcu_read_unlock()) in process > context and updates in softirq/bh/irq context, you can see deadlocks. yeah - but in the PREEMPT_REALTIME kernel there are simply no irq or softirq contexts in process contexts - everything is a task. So everything can (and does) block. Ingo - 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/