From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261625AbUKOPgJ (ORCPT ); Mon, 15 Nov 2004 10:36:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261627AbUKOPgI (ORCPT ); Mon, 15 Nov 2004 10:36:08 -0500 Received: from fw.osdl.org ([65.172.181.6]:45197 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S261625AbUKOPgB (ORCPT ); Mon, 15 Nov 2004 10:36:01 -0500 Date: Mon, 15 Nov 2004 07:35:47 -0800 (PST) From: Linus Torvalds To: David Howells cc: Andrew Morton , davidm@snapgear.com, linux-kernel@vger.kernel.org, uclinux-dev@uclinux.org Subject: Re: [PATCH] VM routine fixes In-Reply-To: <26123.1100524499@redhat.com> Message-ID: References: <20041112023817.247af548.akpm@osdl.org> <20041111143148.76dcaba4.akpm@osdl.org> <200411081432.iA8EWfmh023432@warthog.cambridge.redhat.com> <19844.1100255635@redhat.com> <20942.1100257558@redhat.com> <26123.1100524499@redhat.com> 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 On Mon, 15 Nov 2004, David Howells wrote: > > So not having an MMU, page tables or PTEs or any requirement for operations > that act upon them is not enough? No. It's a matter of abstraction. If you can _abstract_ the thing away, that's fine. I don't want more #ifdef's in source code, but you can have a totally different file that doesnt' do the things that aren't appropriate for non-MMU. Yes, we've already got #ifdef's in code, but the point is that we don't add them unless there is serious _need_. And even then it's a sign of trouble. In this case, the sign of trouble is bigger than the need. uClinux might as well have a dummy "struct vm_operations", if only to make the damn thing look more like real Linux. Linus