From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Snook Subject: [PATCH 8/24] make atomic_read() behave consistently on i386 Date: Thu, 9 Aug 2007 09:49:14 -0400 Message-ID: <20070809134914.GA15811@shell.boston.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: 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 To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, torvalds@linux-foundation.org Return-path: Received: from mx1.redhat.com ([66.187.233.31]:45454 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762051AbXHINtv (ORCPT ); Thu, 9 Aug 2007 09:49:51 -0400 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Chris Snook Make atomic_read() volatile on i386, to ensure memory is actually read each time. Signed-off-by: Chris Snook --- linux-2.6.23-rc2-orig/include/asm-i386/atomic.h 2007-07-08 19:32:17.000000000 -0400 +++ linux-2.6.23-rc2/include/asm-i386/atomic.h 2007-08-09 06:47:47.000000000 -0400 @@ -25,7 +25,7 @@ typedef struct { int counter; } atomic_t * * Atomically reads the value of @v. */ -#define atomic_read(v) ((v)->counter) +#define atomic_read(v) (*(volatile int *)&(v)->counter) /** * atomic_set - set atomic variable