From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures Date: Wed, 15 Aug 2007 11:45:20 -0700 Message-ID: <20070815184520.GG9645@linux.vnet.ibm.com> References: <20070815153335.GA23593@gondor.apana.org.au> <20070809131423.GA9927@shell.boston.redhat.com> <46C2D6F3.3070707@s5r6.in-berlin.de> <46C2FADB.7020407@s5r6.in-berlin.de> <20070815142516.GB9645@linux.vnet.ibm.com> <4413.1187201997@redhat.com> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Herbert Xu , Satyam Sharma , Stefan Richter , Christoph Lameter , Chris Snook , Linux Kernel Mailing List , linux-arch@vger.kernel.org, Linus Torvalds , netdev@vger.kernel.org, Andrew Morton , 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, segher@kernel.crashing.org To: David Howells Return-path: Received: from e4.ny.us.ibm.com ([32.97.182.144]:51779 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762777AbXHOSpY (ORCPT ); Wed, 15 Aug 2007 14:45:24 -0400 Content-Disposition: inline In-Reply-To: <4413.1187201997@redhat.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Aug 15, 2007 at 07:19:57PM +0100, David Howells wrote: > Herbert Xu wrote: > > > Let's turn this around. Can you give a single example where > > the volatile semantics is needed in a legitimate way? > > Accessing H/W registers? But apart from that... Communicating between process context and interrupt/NMI handlers using per-CPU variables. Thanx, Paul