From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 2 May 2002 19:43:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 2 May 2002 19:43:07 -0400 Received: from dsl-213-023-038-046.arcor-ip.net ([213.23.38.46]:34467 "EHLO starship") by vger.kernel.org with ESMTP id ; Thu, 2 May 2002 19:43:06 -0400 Content-Type: text/plain; charset=US-ASCII From: Daniel Phillips To: Andrea Arcangeli Subject: Re: Bug: Discontigmem virt_to_page() [Alpha,ARM,Mips64?] Date: Fri, 3 May 2002 01:42:56 +0200 X-Mailer: KMail [version 1.3.2] Cc: "Martin J. Bligh" , linux-kernel@vger.kernel.org In-Reply-To: <20020502153402.A11414@dualathlon.random> <20020502180632.I11414@dualathlon.random> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Message-Id: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 02 May 2002 18:06, Andrea Arcangeli wrote: > On Wed, May 01, 2002 at 05:42:40PM +0200, Daniel Phillips wrote: > > On Thursday 02 May 2002 17:35, Andrea Arcangeli wrote: > > > On Thu, May 02, 2002 at 08:18:33AM -0700, Martin J. Bligh wrote: > > > > At the moment I use the contig memory model (so we only use discontig for > > > > NUMA support) but I may need to change that in the future. > > > > > > I wasn't thinking at numa-q, but regardless numa-Q fits perfectly into > > > the current discontigmem-numa model too as far I can see. > > > > No it doesn't. The config_discontigmem model forces all zone_normal memory > > to be on node zero, so all the remaining nodes can only have highmem locally. > > You can trivially map the phys mem between 1G and 1G+256M to be in a > direct mapping between 3G+256M and 3G+512M, then you can put such 256M > at offset 1G into the ZONE_NORMAL of node-id 1 with discontigmem too. Andrea, I'm re-reading this and I'm guilty of misreading your 3G+512M, what you meant is PAGE_OFFSET+512M. Yes, in fact this is exactly what config_nonlinear does. Config_discontigmem does not do this, not without your 'trivial map', and that's all config_nonlinear is: a trivial map done in an organized way. This same trivial mapping is capable of replacing all known non-numa uses of config_discontigmem. -- Daniel