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From: John Baldwin <jhb@FreeBSD.org>
To: freebsd-current@freebsd.org
Date: Fri, 2 Sep 2005 14:40:11 -0400
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Cc: Don Lewis <truckman@freebsd.org>, rwatson@freebsd.org, current@freebsd.org
Subject: Re: Witness patch
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On Thursday 01 September 2005 11:52 pm, Don Lewis wrote:
> On  1 Sep, John Baldwin wrote:
> > This patch forces witness to complain if any mutex is held when Giant is
> > locked to enforce Giant being the first mutex in the lock order.  This
> > might help track down some of the network LORs being reported recently.
> >
> > http://www.FreeBSD.org/~jhb/patches/witness.patch
>
> I think it would make sense to print different messages for the
> different trigger conditions.

Hmm, I guess I view them as all just being reversals, and that we have some 
implicit orders that go something like this:

sleepable locks --> Giant --> non-sleepable locks --> spin locks

-- 
John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org