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To: Robert Watson <rwatson@FreeBSD.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 12 Jun 2006 08:08:43 +0100."
	<20060612080504.W26634@fledge.watson.org> 
Date: Mon, 12 Jun 2006 07:40:13 +0000
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Cc: current@FreeBSD.org, Kris Kennaway <kris@obsecurity.org>
Subject: Re: FILEDESC_LOCK() implementation 
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In message <20060612080504.W26634@fledge.watson.org>, Robert Watson writes:

>At least in the VFS and socket code, you want a notion of acquiring both and 
>dropping one, or upgrading/downgrading.  The logic tends to go something like 
>this:

That's different from what FILEDESC needs.  FILEDESC has two different
classes of operations: cheap/non-sleeping and expensive/sleeping

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.