From owner-freebsd-hackers@FreeBSD.ORG  Thu Apr 26 21:50:16 2007
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To: hselasky@c2i.net
From: "M. Warner Losh" <imp@bsdimp.com>
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	Thu, 26 Apr 2007 15:47:05 -0600 (MDT)
Cc: freebsd-hackers@freebsd.org
Subject: Re: msleep() on recursivly locked mutexes
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In message: <200704262136.33196.hselasky@c2i.net>
            Hans Petter Selasky <hselasky@c2i.net> writes:
: Are there any comments on integrating this functionality into msleep(), and 
: adding mtx_drop_recurse() and mtx_pickup_recurse() to the FreeBSD kernel?

This is generally a bad idea.  We allow it for Giant because it has to
be acquired everywhere and we have to drop it in some extremely ugly
places.  To enshrine this behavior for all mutexes strikes me as ill
advised.  Adding additional hacks to recursive mutexes seems wrong to
my way of thinking.

Warner