Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937557AbXHPCRe (ORCPT ); Wed, 15 Aug 2007 22:17:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760390AbXHPCRR (ORCPT ); Wed, 15 Aug 2007 22:17:17 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:59596 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759961AbXHPCRN (ORCPT ); Wed, 15 Aug 2007 22:17:13 -0400 Date: Wed, 15 Aug 2007 19:17:10 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Paul Mackerras cc: Herbert Xu , "Paul E. McKenney" , Satyam Sharma , Stefan Richter , 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 Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures In-Reply-To: Message-ID: References: <20070809131423.GA9927@shell.boston.redhat.com> <46C2D6F3.3070707@s5r6.in-berlin.de> <18115.35524.56393.347841@cargo.ozlabs.ibm.com> <20070816003948.GY9645@linux.vnet.ibm.com> <18115.44462.622801.683446@cargo.ozlabs.ibm.com> <20070816020042.GA30650@gondor.apana.org.au> <18115.45316.702491.681906@cargo.ozlabs.ibm.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: 694 Lines: 19 On Wed, 15 Aug 2007, Christoph Lameter wrote: > On Thu, 16 Aug 2007, Paul Mackerras wrote: > > > > We don't need to reload sk->sk_prot->memory_allocated here. > > > > Are you sure? How do you know some other CPU hasn't changed the value > > in between? > > The cpu knows because the cacheline was not invalidated. Crap my statement above is wrong..... We do not care that the value was changed otherwise we would have put a barrier in there. - 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/