Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765980AbXHTUi0 (ORCPT ); Mon, 20 Aug 2007 16:38:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762017AbXHTUcH (ORCPT ); Mon, 20 Aug 2007 16:32:07 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:52401 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755284AbXHTUcG (ORCPT ); Mon, 20 Aug 2007 16:32:06 -0400 Date: Mon, 20 Aug 2007 13:32:05 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Mathieu Desnoyers cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, mingo@redhat.com Subject: Re: [patch 01/23] Fall back on interrupt disable in cmpxchg8b on 80386 and 80486 In-Reply-To: <20070820201822.597720007@polymtl.ca> Message-ID: References: <20070820201519.512791382@polymtl.ca> <20070820201822.597720007@polymtl.ca> 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: 730 Lines: 15 On Mon, 20 Aug 2007, Mathieu Desnoyers wrote: > already present in cmpxchg_386_u32 tells much about how this cmpxchg > implementation should not be used in a SMP context. However, the cmpxchg_local > can perfectly use this fallback, since it only needs to be atomic wrt the local > cpu. Do you have an example where the use of cmpxchg_local is a performance benefit when actually used in code? cmpxchg is already problematic functionality since it is not available on all platforms. - 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/