From owner-freebsd-hackers Wed Sep 23 18:16:49 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id SAA24028 for freebsd-hackers-outgoing; Wed, 23 Sep 1998 18:16:49 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from freefall.freebsd.org (freefall.FreeBSD.ORG [204.216.27.21]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id SAA24011 for ; Wed, 23 Sep 1998 18:16:39 -0700 (PDT) (envelope-from rivers@dignus.com) Received: from elvis.vnet.net (elvis.vnet.net [166.82.1.5]) by freefall.freebsd.org (8.8.8/8.8.5) with ESMTP id SAA27429 for ; Wed, 23 Sep 1998 18:16:38 -0700 (PDT) Received: from dignus.com (ponds.vnet.net [166.82.177.48]) by elvis.vnet.net (8.8.8/8.8.4) with ESMTP id VAA06839 for ; Wed, 23 Sep 1998 21:16:31 -0400 (EDT) Received: from lakes.dignus.com (lakes [10.0.0.3]) by dignus.com (8.8.8/8.8.5) with ESMTP id VAA25632 for ; Wed, 23 Sep 1998 21:55:42 -0400 (EDT) Received: (from rivers@localhost) by lakes.dignus.com (8.8.8/8.6.9) id VAA15313 for freebsd-hackers@freefall.cdrom.com; Wed, 23 Sep 1998 21:20:24 -0400 (EDT) Date: Wed, 23 Sep 1998 21:20:24 -0400 (EDT) From: Thomas David Rivers Message-Id: <199809240120.VAA15313@lakes.dignus.com> To: freebsd-hackers@freefall.cdrom.com Subject: Idea for a small project... Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG I realize this is making work, but, if someone is looking for a way to contribute, or a graduate student/senior computer science major is looking for a good term project... this might be one. The Pentium chip has improved support for debugging programs, including a hardware assisted databreak manager. Unfortunately, the FreeBSD kernel doesn't take advantage of this facility. Which leaves debuggers to do "watchpoints" by single stepping the code and checking to see if the watchpoint had occurred. A nice improvement to FreeBSD would be to improve the ptrace() support so that it used the hardware assisted feature when running on a Pentium. The feature is limited in the number of breakpoints you can manage; extra credit would be to not expose this limitation. Use the hardware break point feature for the first N watch points (I believe N would be 4 in this case) and the current software approach when you have more. - Dave Rivers - To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message