From owner-freebsd-arch Thu May 18 22:17:20 2000 Delivered-To: freebsd-arch@freebsd.org Received: from obie.softweyr.com (obie.softweyr.com [204.68.178.33]) by hub.freebsd.org (Postfix) with ESMTP id 11C3237BD10 for ; Thu, 18 May 2000 22:17:17 -0700 (PDT) (envelope-from wes@softweyr.com) Received: from softweyr.com (homer.softweyr.com [204.68.178.39]) by obie.softweyr.com (8.8.8/8.8.8) with ESMTP id XAA17555; Thu, 18 May 2000 23:17:06 -0600 (MDT) (envelope-from wes@softweyr.com) Message-ID: <3924CEE4.55551D82@softweyr.com> Date: Thu, 18 May 2000 23:19:32 -0600 From: Wes Peters Organization: Softweyr LLC X-Mailer: Mozilla 4.7 [en] (X11; U; FreeBSD 4.0-STABLE i386) X-Accept-Language: en MIME-Version: 1.0 To: Chuck Paterson Cc: Doug Rabson , arch@FreeBSD.ORG Subject: Re: A new api for asynchronous task execution References: <200005181557.JAA05148@berserker.bsdi.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Chuck Paterson wrote: > > } > }Wouldn't it make more sense to provide an inversion-proof semaphore? > }Or is that what they're doing? > > Not quite sure what you mean. The lock checking done > now is to detect without actually having to have the deadlock > occur the following > > thread 1 acquires lock "a" and then tries to acquire lock "b" > thread 2 acquires lock "b" and then tries to acquire lock "a" > > There isn't really any automagic fix for this. Ah, I misunderstood, this is a deadly embrace. There are automagic fixes, but they get expensive REALLY fast. Still, it's a good option to turn on for debugging. > If you are talking about running processes in > order based on scheduling priority, this is propagated > though mutexs which have been blocked on. No, speaking of temporarily elevating the priority of a process holding a lock to the highest priority of all processes blocking on the lock. -- "Where am I, and what am I doing in this handbasket?" Wes Peters Softweyr LLC wes@softweyr.com http://softweyr.com/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message