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Date: Thu, 6 Jul 2006 10:40:27 +0200
From: Maxime Henrion <mux@FreeBSD.org>
To: Scott Long <scottl@FreeBSD.org>
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Cc: Perforce Change Reviews <perforce@freebsd.org>
Subject: Re: PERFORCE change 100686 for review
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Scott Long wrote:
> http://perforce.freebsd.org/chv.cgi?CH=100686
> 
> Change 100686 by scottl@scottl-wv1u on 2006/07/06 03:47:59
> 
> 	Use a sleep mutex to protect kernel environment handling instead of
> 	an sx lock.  The sx lock seemed to only be used to get around the
> 	copyout case in kenv(KENV_DUMP) path.  Fix that path to safely use a
> 	sleep lock instead.

Actually, the sx lock was not used for that but simply for the usual
reason we use sx locks: to allow multiple readers to read the kernel
environment in parallel.  This is just FYI, I don't mind you changing
it to a mutex, since kenv() is quite rarely used and it probably doesn't
benefit much from the sx lock (it may even get pessimized by it).

Cheers,
Maxime