From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932485AbWDUWNb (ORCPT ); Fri, 21 Apr 2006 18:13:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932486AbWDUWNb (ORCPT ); Fri, 21 Apr 2006 18:13:31 -0400 Received: from canuck.infradead.org ([205.233.218.70]:26587 "EHLO canuck.infradead.org") by vger.kernel.org with ESMTP id S932485AbWDUWNb (ORCPT ); Fri, 21 Apr 2006 18:13:31 -0400 Subject: Re: [PATCH] Shrink rbtree From: David Woodhouse To: Hugh Dickins Cc: Nick Piggin , Mikael Starvik , akpm@osdl.org, andrea@suse.de, linux-kernel@vger.kernel.org In-Reply-To: References: <1145623663.11909.139.camel@pmac.infradead.org> <4448D8BF.9040601@yahoo.com.au> <1145646503.11909.222.camel@pmac.infradead.org> Content-Type: text/plain Date: Fri, 21 Apr 2006 23:12:53 +0100 Message-Id: <1145657573.11909.226.camel@pmac.infradead.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by canuck.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2006-04-21 at 21:57 +0100, Hugh Dickins wrote: > > } __attribute__((aligned(sizeof(long)))); > /* > * On most architectures that alignment is already the case; but > * must be enforced here for CRIS, to let the least signficant bit > * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON. > */ > > You can often get away with it - I notice we never added the same > alignment to struct anon_vma, which in theory needed it just as much. > Some accident of how structures are packed into slabs on CRIS, I suppose. That sounds very strange to me, but it's harmless enough to add the explicit alignment. -- dwmw2