From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264446AbTDPOzq (for ); Wed, 16 Apr 2003 10:55:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264447AbTDPOzq (for ); Wed, 16 Apr 2003 10:55:46 -0400 Received: from pizda.ninka.net ([216.101.162.242]:59269 "EHLO pizda.ninka.net") by vger.kernel.org with ESMTP id S264446AbTDPOzp (for ); Wed, 16 Apr 2003 10:55:45 -0400 Date: Wed, 16 Apr 2003 08:00:44 -0700 (PDT) Message-Id: <20030416.080044.25878686.davem@redhat.com> To: ak@muc.de Cc: willy@debian.org, 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: <20030416150427.GA2496@averell> References: <20030416144312.GA2327@averell> <20030416145532.GA1505@parcelfarce.linux.theplanet.co.uk> <20030416150427.GA2496@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 17:04:27 +0200 Sure, but you use a 64bit read/store in set_bit/clear_bit etc., right? If yes then you can't use this unless you rewrite them to use 32bit store - otherwise it will conflict with the atomic_t counter in the 64bit slot which is not protected. It will be protected by the same spinlock, look at how the thing works :-)