Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261556AbVCRMzK (ORCPT ); Fri, 18 Mar 2005 07:55:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261589AbVCRMzK (ORCPT ); Fri, 18 Mar 2005 07:55:10 -0500 Received: from smtp.Lynuxworks.com ([207.21.185.24]:18185 "EHLO smtp.lynuxworks.com") by vger.kernel.org with ESMTP id S261556AbVCRMzE (ORCPT ); Fri, 18 Mar 2005 07:55:04 -0500 Date: Fri, 18 Mar 2005 04:56:41 -0800 To: "Paul E. McKenney" Cc: mingo@elte.hu, dipankar@in.ibm.com, shemminger@osdl.org, akpm@osdl.org, torvalds@osdl.org, rusty@au1.ibm.com, tgall@us.ibm.com, jim.houston@comcast.net, manfred@colorfullife.com, gh@us.ibm.com, linux-kernel@vger.kernel.org Subject: Re: Real-Time Preemption and RCU Message-ID: <20050318125641.GA5107@nietzsche.lynx.com> References: <20050318002026.GA2693@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050318002026.GA2693@us.ibm.com> User-Agent: Mutt/1.5.6+20040907i From: Bill Huey (hui) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 786 Lines: 29 On Thu, Mar 17, 2005 at 04:20:26PM -0800, Paul E. McKenney wrote: > 5. Scalability -and- Realtime Response. ... > void > rcu_read_lock(void) > { > preempt_disable(); > if (current->rcu_read_lock_nesting++ == 0) { > current->rcu_read_lock_ptr = > &__get_cpu_var(rcu_data).lock; > read_lock(current->rcu_read_lock_ptr); > } > preempt_enable(); > } Ok, here's a rather unsure question... Uh, is that a sleep violation if that is exclusively held since it can block within an atomic critical section (deadlock) ? bill - 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/