Date: Thu, 18 May 2000 15:09:25 -0700 From: Peter Wemm <peter@netplex.com.au> To: Doug Rabson <dfr@nlsystems.com> Cc: Wes Peters <wes@softweyr.com>, arch@FreeBSD.ORG Subject: Re: A new api for asynchronous task execution Message-ID: <20000518220925.E8DB41CE1@overcee.netplex.com.au> In-Reply-To: Message from Doug Rabson <dfr@nlsystems.com> of "Thu, 18 May 2000 21:07:43 BST." <Pine.BSF.4.21.0005182105470.73457-100000@salmon.nlsystems.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Doug Rabson wrote: > On Thu, 18 May 2000, Wes Peters wrote: > > > Doug Rabson wrote: > > > > > > The BSD/OS mutex code includes a compile-time-selected debugging feature > > > which automatically detects locking hierarchy violations. Anyway, using a > > > mutex here doesn't add to locking complexity since the mutex would be > > > exited before calling the task's callback and re-entered after. > > > > Wouldn't it make more sense to provide an inversion-proof semaphore? > > Or is that what they're doing? > > I'm sure Chuck can describe it better than me. As I understand it, the > BSD/OS object is a simple counting mutex which comes in both blocking and > spinning forms. There is a set of strict rules for mutex nesting which the > debugging code uses to detect e.g. deadly embrace etc. That would be the WITNESS stuff, right? (for verifying and enforcing the rules) Cheers, -Peter -- Peter Wemm - peter@FreeBSD.org; peter@yahoo-inc.com; peter@netplex.com.au "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20000518220925.E8DB41CE1>