Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761863AbXHNWbd (ORCPT ); Tue, 14 Aug 2007 18:31:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752686AbXHNWbR (ORCPT ); Tue, 14 Aug 2007 18:31:17 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:51794 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751393AbXHNWbQ (ORCPT ); Tue, 14 Aug 2007 18:31:16 -0400 Date: Tue, 14 Aug 2007 15:31:12 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Chris Snook cc: 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 0/24] make atomic_read() behave consistently across all architectures In-Reply-To: <20070809131423.GA9927@shell.boston.redhat.com> Message-ID: References: <20070809131423.GA9927@shell.boston.redhat.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 780 Lines: 16 On Thu, 9 Aug 2007, Chris Snook wrote: > This patchset makes the behavior of atomic_read uniform by removing the > volatile keyword from all atomic_t and atomic64_t definitions that currently > have it, and instead explicitly casts the variable as volatile in > atomic_read(). This leaves little room for creative optimization by the > compiler, and is in keeping with the principles behind "volatile considered > harmful". volatile is generally harmful even in atomic_read(). Barriers control visibility and AFAICT things are fine. - 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/