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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 16:59:42 -0500
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	<200401161523.32120.jhb@FreeBSD.org> <xzpr7xzsj20.fsf@dwp.des.no>
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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 04:03 pm, Dag-Erling Sm=F8rgrav wrote:
> John Baldwin <jhb@FreeBSD.org> writes:
> > 	while (newfdp blah fdp) {
> > 		FILEDESC_UNLOCK(fdp);
> > 		FILEDESC_LOCK(newfdp);
> > 		fd_growtable(newfdp);
> > 		FILEDESC_UNLOCK(newfdp);
> > 		FILEDESC_LOCK(fdp);
> > 	}
>
> I guess...  seems like a bloody waste of cycles=20

You could only lock newfdp #ifdef INVARIANTS perhaps since that is the only=
=20
reason you are doing it.  That doesn't pessimize production kernels while=20
still letting your assertions work ok.  You could also perhaps tweak the=20
mtx_assert to somehow check the state of the fd pointer to see if it is a n=
ew=20
table (refcount of 0 or some such)

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