Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 9 Nov 2000 12:58:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 9 Nov 2000 12:58:10 -0500 Received: from mail-03-real.cdsnet.net ([63.163.68.110]:61196 "HELO mail-03-real.cdsnet.net") by vger.kernel.org with SMTP id ; Thu, 9 Nov 2000 12:57:53 -0500 Message-ID: <3A0AE653.70D91891@mvista.com> Date: Thu, 09 Nov 2000 10:00:51 -0800 From: George Anzinger Organization: Monta Vista Software X-Mailer: Mozilla 4.72 [en] (X11; I; Linux 2.2.14-VPN i586) X-Accept-Language: en MIME-Version: 1.0 To: Andi Kleen CC: david , Linux Kernel List Subject: Re: fpu now a must in kernel In-Reply-To: <3A09E161.ACB11253@ihug.co.nz> <20001109153648.A21769@gruyere.muc.suse.de> 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 Andi Kleen wrote: > > On Thu, Nov 09, 2000 at 12:27:29PM +1300, david wrote: > > > > 2 . put the save / restore code in my code (NOT! GOOD! i do not wont to > > do it this way it is not the right way) > > It is the right way because it only penalizes your code, not everybody else. > This is a MAJOR drag on preemptability. MUCH better to keep it out of the kernel. Barring that, since context switch does not (and should not) save/restore fp state, the using code must be preemption locked. Sound folks won't like this. Maybe you could explain why you think you need this and the community here could suggest an alternative way to do the same or better. By the way, since the kernel is not yet preemptable, you could use empty macros to lock preemption. This way, when preemption comes (2.5) your code will be easily found. George - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/