From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757388AbYCARWl (ORCPT ); Sat, 1 Mar 2008 12:22:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754667AbYCARWb (ORCPT ); Sat, 1 Mar 2008 12:22:31 -0500 Received: from mx1.redhat.com ([66.187.233.31]:34405 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754556AbYCARWa (ORCPT ); Sat, 1 Mar 2008 12:22:30 -0500 Date: Sat, 1 Mar 2008 12:21:56 -0500 From: Rik van Riel To: Christoph Lameter Cc: linux-kernel@vger.kernel.org, Mel Gorman , Nick Piggin , Andrew Morton , apw@shadowen.org, linux-mm@kback.org Subject: Re: [rfc 10/10] Pageflags land grab Message-ID: <20080301122156.5994b949@bree.surriel.com> In-Reply-To: <20080301040622.220638278@sgi.com> References: <20080301040534.797979115@sgi.com> <20080301040622.220638278@sgi.com> Organization: Red Hat, Inc. X-Mailer: Claws Mail 3.0.2 (GTK+ 2.10.4; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 29 Feb 2008 20:05:44 -0800 Christoph Lameter wrote: > We have enough page flags after vmemmap no longer uses section ids. > > Reserve 5 of the 6 saved flags for functionality that is currently > under development in the VM. > > The new flags are only available if either of these conditions are met: > > 1. 64 Bit system. (then we have 8 more free of the 32) > > 2. !NUMA. In that case 2 bits are needed for the zone > id which leaves 30 page flag bits. Of those we use 24. 6 left. > > 3. !SPARSEMEM. In that case we use 5 bits of the 30 available > for the node. 1 leftover. > > 4. SPARSEMEM_VMEMMAP. Case 3 applies. Nice! I like your patch series. -- All rights reversed.