From owner-freebsd-smp Sun Jun 25 23:31:59 2000 Delivered-To: freebsd-smp@freebsd.org Received: from tinker.exit.com (exit-gw.power.net [207.151.46.196]) by hub.freebsd.org (Postfix) with ESMTP id D62FA37B9AC for ; Sun, 25 Jun 2000 23:31:54 -0700 (PDT) (envelope-from frank@exit.com) Received: from realtime.exit.com (realtime.exit.com [206.223.0.5]) by tinker.exit.com (8.9.3/8.9.3) with ESMTP id XAA05675; Sun, 25 Jun 2000 23:31:52 -0700 (PDT) (envelope-from frank@exit.com) Received: (from frank@localhost) by realtime.exit.com (8.9.3/8.9.3) id XAA43949; Sun, 25 Jun 2000 23:31:51 -0700 (PDT) (envelope-from frank) From: Frank Mayhar Message-Id: <200006260631.XAA43949@realtime.exit.com> Subject: Re: SMP meeting summary In-Reply-To: <200006251713.KAA09348@usr02.primenet.com> from Terry Lambert at "Jun 25, 2000 05:13:07 pm" To: Terry Lambert Date: Sun, 25 Jun 2000 23:31:51 -0700 (PDT) Cc: Jason Evans , smp@FreeBSD.ORG Reply-To: frank@exit.com Organization: Exit Consulting X-Copyright0: Copyright 2000 Frank Mayhar. All Rights Reserved. X-Copyright1: Permission granted for electronic reproduction as Usenet News or email only. X-Mailer: ELM [version 2.4ME+ PL68 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Terry Lambert wrote: > In Streams, this was addressed by removing two primitives, and creating > what are called "priority bands" to deal with the issue (I worked for > Novell USG when UnixWare was going to 2.0 and integrating the ES/MP code > into the SVR4 base, and saw much of this happen). Speaking of which, there has _got_ to be a better way. It's possible when dealing with Streams to get into nested-lock situations where you need a lock with a lower priority and it's not possible (due to constraints elsewhere) to raise the priority of the lock. And, of course, it's always dangerous to raise the priority of an existing lock, since you may miss a case. I'm not sure that interrupt threads are the right way to go either, though. If there even _is_ a "right" way. -- Frank Mayhar frank@exit.com http://www.exit.com/ Exit Consulting http://store.exit.com/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message