From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261670AbTKXXcU (ORCPT ); Mon, 24 Nov 2003 18:32:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261683AbTKXXcU (ORCPT ); Mon, 24 Nov 2003 18:32:20 -0500 Received: from mtvcafw.sgi.com ([192.48.171.6]:1394 "EHLO zok.sgi.com") by vger.kernel.org with ESMTP id S261670AbTKXXcR (ORCPT ); Mon, 24 Nov 2003 18:32:17 -0500 Date: Mon, 24 Nov 2003 15:31:55 -0800 To: Andrew Morton , colpatch@us.ibm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mbligh@aracnet.com Subject: Re: [RFC] Simplify node/zone portion of page->flags Message-ID: <20031124233155.GA27541@sgi.com> Mail-Followup-To: Andrew Morton , colpatch@us.ibm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mbligh@aracnet.com References: <3FBEB867.9080506@us.ibm.com> <20031123144052.1f0d5071.akpm@osdl.org> <20031123224903.GB21617@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20031123224903.GB21617@sgi.com> User-Agent: Mutt/1.5.4i From: jbarnes@sgi.com (Jesse Barnes) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 23, 2003 at 02:49:03PM -0800, Jesse Barnes wrote: > On Sun, Nov 23, 2003 at 02:40:52PM -0800, Andrew Morton wrote: > > > zone_num. This makes it trivial to recover either the node or zone > > > number with a simple bitshift. There are many places in the kernel > > > where we do things like: page_zone(page)->zone_pgdat->node_id to > > > determine the node a page belongs to. With this patch we save several > > > pointer dereferences, and it boils down to shifting some bits. > > > > This rather conflicts with the patch from Jesse which I have. Can you guys > > work that out and let me know when you're done? > > I like Matt's patch, but haven't tested it yet. I'll try it out on > Monday. Matt, this looks ok (at least it boots on my test system). I wasn't able test it on a very large system though, but it looks functionally identical to the patch in Andrew's tree. Btw, you probably want to put () around NODEZONE_SHIFT + ZONES_SHIFT in page_nodenum() otherwise gcc will complain loudly. Jesse