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Date: Thu, 22 Nov 2007 12:00:01 -0800
From: Alfred Perlstein <alfred@freebsd.org>
To: Max Laier <max@love2party.net>
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Cc: attilio@freebsd.org, Stephan Uphoff <ups@freebsd.org>,
	freebsd-arch@freebsd.org
Subject: Re: rwlocks, correctness over speed.
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* Max Laier <max@love2party.net> [071122 07:46] wrote:
> On Wednesday 21 November 2007, Alfred Perlstein wrote:
> > In summary, I am proposing (temporarily) making read-recursion
> > on rwlocks not supported in order to avoid livelock due to writer
> > starvation.
> >
> 
> rwlocks are already used in places that do recursive reads.  The one place 


Max, I think what will happen is that we will mark further uses
or read locks as recursive as "not supported", perhaps witness
can temporarily grow a flag to ignore recursive read ops until
the existing infrastructure is fixed.

I will not get into alternatives for pfil, as it seems you've mostly
worked it out.

-Alfred