From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 25 May 2002 14:24:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 25 May 2002 14:24:13 -0400 Received: from relay03.valueweb.net ([216.219.253.237]:43282 "EHLO relay03.valueweb.net") by vger.kernel.org with ESMTP id ; Sat, 25 May 2002 14:24:12 -0400 Message-ID: <3CEFD65A.ED871095@opersys.com> Date: Sat, 25 May 2002 14:22:18 -0400 From: Karim Yaghmour X-Mailer: Mozilla 4.75 [en] (X11; U; Linux 2.4.16 i686) X-Accept-Language: en, French/Canada, French/France, fr-FR, fr-CA MIME-Version: 1.0 To: Linus Torvalds CC: Wolfgang Denk , linux-kernel@vger.kernel.org Subject: Re: patent on O_ATOMICLOOKUP [Re: [PATCH] loopable tmpfs (2.4.17)] In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Linus Torvalds wrote: > - I think the microkernel approach is fundamentally broken. Karim claims > there is no priority inversion, but he must have his blinders on. Every > single spinlock in the kernel assumes that the kernel isn't preempted, > which means that user apps that can preempt the kernel cannot use them. Blinders ehh... Well, if you would care to ask I would answer. In reality, what you point out is actually a non-issue since the hard-rt user-land tasks are not allowed to call on normal Linux services. They can only call on RTAI services which are exported by an extra soft-int. These services are hard-rt, so there's no problem there. Please, download the thing and play with it. Or, at the very least, ask about how it works and we'll be glad to explain. Karim =================================================== Karim Yaghmour karim@opersys.com Embedded and Real-Time Linux Expert ===================================================