Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758716AbZCTPi7 (ORCPT ); Fri, 20 Mar 2009 11:38:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754225AbZCTPiv (ORCPT ); Fri, 20 Mar 2009 11:38:51 -0400 Received: from gw.goop.org ([64.81.55.164]:53068 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751315AbZCTPiu (ORCPT ); Fri, 20 Mar 2009 11:38:50 -0400 Message-ID: <49C3B886.8080408@goop.org> Date: Fri, 20 Mar 2009 08:38:46 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.19 (X11/20090105) MIME-Version: 1.0 To: paulmck@linux.vnet.ibm.com CC: Nick Piggin , Avi Kivity , Linux Kernel Mailing List , Linux Memory Management List , Xen-devel , Jan Beulich , Ingo Molnar Subject: Re: Question about x86/mm/gup.c's use of disabled interrupts References: <49C148AF.5050601@goop.org> <200903191232.05459.nickpiggin@yahoo.com.au> <49C2818B.9060201@goop.org> <20090320044029.GD6807@linux.vnet.ibm.com> In-Reply-To: <20090320044029.GD6807@linux.vnet.ibm.com> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 709 Lines: 19 Paul E. McKenney wrote: >> Ah, interesting. So disabling interrupts prevents the RCU free from >> happening, and non-atomic pte fetching is a non-issue. So it doesn't >> address the PAE side of the problem. >> > > This would be rcu_sched, correct? > I guess? Whatever it is that ends up calling all the rcu callbacks after the idle. A cpu with disabled interrupts can't go through idle, right? Or is there an explicit way to hold off rcu? J -- 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/