From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264442AbTDPOxp (for ); Wed, 16 Apr 2003 10:53:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264445AbTDPOxp (for ); Wed, 16 Apr 2003 10:53:45 -0400 Received: from pizda.ninka.net ([216.101.162.242]:54661 "EHLO pizda.ninka.net") by vger.kernel.org with ESMTP id S264442AbTDPOxj (for ); Wed, 16 Apr 2003 10:53:39 -0400 Date: Wed, 16 Apr 2003 07:58:37 -0700 (PDT) Message-Id: <20030416.075837.03516293.davem@redhat.com> To: ak@muc.de Cc: akpm@digeo.com, linux-kernel@vger.kernel.org, anton@samba.org, schwidefsky@de.ibm.com, davidm@hpl.hp.com, matthew@wil.cx, ralf@linux-mips.org, rth@redhat.com Subject: Re: Reduce struct page by 8 bytes on 64bit From: "David S. Miller" In-Reply-To: <20030416145853.GA2421@averell> References: <20030416144312.GA2327@averell> <20030416.073814.124147956.davem@redhat.com> <20030416145853.GA2421@averell> X-FalunGong: Information control. X-Mailer: Mew version 2.1 on Emacs 21.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Andi Kleen Date: Wed, 16 Apr 2003 16:58:53 +0200 In this case part of the unsigned long could be accessed directly using the aliasing. They use the same ATOMIC_HASH() for both atomic_t's and bitops. I don't see how an alias can be generated. This thing must work for any ordering of unsigned long *'s and atomic_t's.