Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934416AbXHJJYr (ORCPT ); Fri, 10 Aug 2007 05:24:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762180AbXHJJYe (ORCPT ); Fri, 10 Aug 2007 05:24:34 -0400 Received: from mx1.redhat.com ([66.187.233.31]:45211 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762075AbXHJJYc (ORCPT ); Fri, 10 Aug 2007 05:24:32 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <46BB46B2.60808@redhat.com> References: <46BB46B2.60808@redhat.com> <20070809134150.GA14890@shell.boston.redhat.com> To: Chris Snook Cc: dhowells@redhat.com, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, torvalds@linux-foundation.org, netdev@vger.kernel.org, akpm@linux-foundation.org, ak@suse.de, heiko.carstens@de.ibm.com, davem@davemloft.net, schwidefsky@de.ibm.com, wensong@linux-vs.org, horms@verge.net.au, wjiang@resilience.com, cfriesen@nortel.com, zlynx@acm.org, rpjday@mindspring.com, jesper.juhl@gmail.com Subject: Re: [PATCH 6/24] make atomic_read() behave consistently on frv X-Mailer: MH-E 8.0.3; nmh 1.2-20070115cvs; GNU Emacs 22.1.50 Date: Fri, 10 Aug 2007 10:23:46 +0100 Message-ID: <2708.1186737826@redhat.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 587 Lines: 14 Chris Snook wrote: > To head off the criticism, I admit this is an oversimplification, and true > busy-waiters should be using cpu_relax(), which contains a barrier. Why would you want to use cpu_relax()? That's there to waste time efficiently, isn't it? Shouldn't you be using smp_rmb() or something like that? David - 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/