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From: John Baldwin <jhb@FreeBSD.org>
To: des@des.no (Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?=)
Date: Fri, 16 Jan 2004 17:26:02 -0500
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cc: "Robin P. Blanchard" <robin.blanchard@gactr.uga.edu>
cc: current@freebsd.org
Subject: Re: Panic with this morning's (~9am EDT, 15 jan 2004) sources.
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On Friday 16 January 2004 05:01 pm, Dag-Erling Sm=F8rgrav wrote:
> John Baldwin <jhb@FreeBSD.org> writes:
> > You could only lock newfdp #ifdef INVARIANTS perhaps since that is the
> > only reason you are doing it.  That doesn't pessimize production kernels
> > while still letting your assertions work ok.
>
> now that's an idea (though it's a bit of a hack)
>
> >                                         You could also perhaps tweak the
> > mtx_assert to somehow check the state of the fd pointer to see if it is=
 a
> > new table (refcount of 0 or some such)
>
> that would pessimize the common case...

Well, only for kernels with INVARIANTS in them. :)  If you do 'if (foo)=20
mtx_assert(...)' then gcc should optimize the whole thing out without=20
invariants.

=2D-=20
John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =3D  http://www.FreeBSD.org