From owner-freebsd-smp Sun Nov 26 18: 6:53 2000 Delivered-To: freebsd-smp@freebsd.org Received: from echunga.lemis.com (freebie.lemis.com [192.109.197.137]) by hub.freebsd.org (Postfix) with ESMTP id C270937B479 for ; Sun, 26 Nov 2000 18:06:48 -0800 (PST) Received: (from grog@localhost) by echunga.lemis.com (8.11.1/8.9.3) id eAR1vaF28731; Mon, 27 Nov 2000 12:27:36 +1030 (CST) (envelope-from grog) Date: Mon, 27 Nov 2000 12:27:36 +1030 From: Greg Lehey To: Jake Burkholder Cc: smp@FreeBSD.ORG Subject: Re: BSD/OS interrupt code Message-ID: <20001127122736.G27697@echunga.lemis.com> References: <20001127015006.5B7BDBA7A@io.yi.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20001127015006.5B7BDBA7A@io.yi.org>; from jburkhol@home.com on Sun, Nov 26, 2000 at 05:50:06PM -0800 Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-418-838-708 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Sunday, 26 November 2000 at 17:50:06 -0800, Jake Burkholder wrote: >> On Sunday, 26 November 2000 at 14:07:49 -0800, Jake Burkholder wrote: >>> Hi, >>> >>> If anyone with access to the BSD/OS code is interested, I've written >>> a little program that runs their interrupt stub code generator in >>> userland. You can then abort(); and disassemble the stub from >>> the core dump to look at the code all in one piece. Makes it much >>> easier to follow. >>> >>> In case you haven't looked, their interrupt handlers are generated >>> by bcopy-ing various blocks of assembler code into an array at >>> runtime, and then poking in arguments and relocating branches. >> >> Interesting. I was wondering whether something similar would be a >> good idea. On the other hand, We don't waste much space by having >> multiple alternate stubs. What's your feeling? > > I suspect that it would be hard to do this for architectures > other than x86, which has a relatively simple instruction format. > > I also think that BSD/OS went a little too far with this, and > have produced code that is very difficult to understand, let > alone maintain. I think its cool what they did, I'm humbled > and amazed that they made it work, but I don't know that its > right for FreeBSD. That's a reasonable objection. Where's your program? Greg -- Finger grog@lemis.com for PGP public key See complete headers for address and phone numbers To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message