From owner-freebsd-arch Mon Nov 29 4:24:22 1999 Delivered-To: freebsd-arch@freebsd.org Received: from ns1.yes.no (ns1.yes.no [195.204.136.10]) by hub.freebsd.org (Postfix) with ESMTP id EA7BD14F0E for ; Mon, 29 Nov 1999 04:24:20 -0800 (PST) (envelope-from eivind@bitbox.follo.net) Received: from bitbox.follo.net (bitbox.follo.net [195.204.143.218]) by ns1.yes.no (8.9.3/8.9.3) with ESMTP id NAA16449 for ; Mon, 29 Nov 1999 13:24:19 +0100 (CET) Received: (from eivind@localhost) by bitbox.follo.net (8.8.8/8.8.6) id NAA63224 for freebsd-arch@freebsd.org; Mon, 29 Nov 1999 13:24:19 +0100 (MET) Received: from pcnet1.pcnet.com (pcnet1.pcnet.com [204.213.232.3]) by hub.freebsd.org (Postfix) with ESMTP id 0A1D514F0E for ; Mon, 29 Nov 1999 04:24:13 -0800 (PST) (envelope-from eischen@vigrid.com) Received: from vigrid.com (pm3-pt60.pcnet.net [206.105.29.134]) by pcnet1.pcnet.com (8.8.7/PCNet) with ESMTP id HAA26932; Mon, 29 Nov 1999 07:24:12 -0500 (EST) Message-ID: <384270AE.D0250340@vigrid.com> Date: Mon, 29 Nov 1999 07:25:18 -0500 From: "Daniel M. Eischen" X-Mailer: Mozilla 4.5 [en] (X11; I; FreeBSD 4.0-CURRENT i386) X-Accept-Language: en MIME-Version: 1.0 To: Julian Elischer Cc: arch@freebsd.org Subject: Re: Threads stuff References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Julian Elischer wrote: > > Yes, I understood them just fine :) I'm still not sold on the new > > syscall gate and IOCB, because I think we have to make at least one > > system call when threads are switched or resumed. > > > > I'm not completely sold on them either. > I just have a gut feeling on it based on doing this for 25 years. Well let's see if we can make them work, now that we know more of the issues. One potential problem I see with placing the IOCBs at a fixed location in the calling threads stack is that you then are tied to having to find TSD for every system call. I say TSD, but really mean you have to go through the same hoops as getting TSD. We don't know how fast this is going to be for i386. I think if we allocate the IOCB from the stack at the time of the system call, it will be faster. If the thread blocks, then kernel can provide enough information so that the UTS upcall can find the IOCB, set the IOCBptr in the current thread, mark the thread as blocked, etc. Dan Eischen eischen@vigrid.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message