Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262545AbUDHUIG (ORCPT ); Thu, 8 Apr 2004 16:08:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262503AbUDHUHv (ORCPT ); Thu, 8 Apr 2004 16:07:51 -0400 Received: from reformers.mr.itd.umich.edu ([141.211.93.147]:41134 "EHLO reformers.mr.itd.umich.edu") by vger.kernel.org with ESMTP id S262754AbUDHT52 (ORCPT ); Thu, 8 Apr 2004 15:57:28 -0400 Date: Thu, 8 Apr 2004 15:57:19 -0400 (EDT) From: Rajesh Venkatasubramanian X-X-Sender: vrajesh@ruby.engin.umich.edu To: Hugh Dickins cc: mbligh@aracnet.com, akpm@osdl.org, andrea@suse.de, linux-kernel@vger.kernel.org Subject: Re: NUMA API for Linux In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1386 Lines: 38 On Thu, 8 Apr 2004, Hugh Dickins wrote: > On Thu, 8 Apr 2004, Rajesh Venkatasubramanian wrote: > > > > I guess using vm_private_data for nonlinear is not a problem because > > we use list i_mmap_nonlinear for nonlinear vmas. > > > > As you have found out vm_private_data is only used if vm_file != NULL > > or VM_RESERVED or VM_DONTEXPAND is set. I think we can revert back to > > i_mmap{_shared} list for such special cases and use prio_tree for > > others. I maybe missing something. Please teach me. > > Sorry, I don't understand what you're proposing here, and why? > Oh, to save 4 bytes of vma by making the special cases use a list, > no need for vm_set_head, and vm_private_data for the driver itself; > but regular vmas use prio_tree, with vm_set_head in vm_private_data. Yeah. You are right. > Hmm, right now it's getting too much for me: can we keep it simplish > for now, and come back to this later? Yeah. This complicates the code further. That's why I didn't touch it now. If things settle down and if we really worry about sizeof vm_area_struct in the future, then we can remove the 8 bytes used by prio_tree. Rajesh - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/