From owner-freebsd-hackers@FreeBSD.ORG  Thu Sep 29 18:59:19 2005
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From: John Baldwin <jhb@FreeBSD.org>
To: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
Date: Thu, 29 Sep 2005 14:55:58 -0400
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Cc: freebsd-hackers@FreeBSD.org, Divacky Roman <xdivac02@stud.fit.vutbr.cz>,
	Stanislav Sedov <stas@310.ru>
Subject: Re: dev_lock() question
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On Thursday 29 September 2005 02:14 pm, Poul-Henning Kamp wrote:
> In message <200509291408.18098.jhb@FreeBSD.org>, John Baldwin writes:
> >Actually, you would think that it could be initialized either via an early
> >SYSINIT() or in the init_mutexes() function in kern_mutex.c and thus not
> > need the early check and avoid penalizing dev_lock().
> >
> >phk, how early his dev_lock needed?
>
> Far too early due to console madness (in syscons I belive).

So would mutex_init() work?  It's called very early in the MD startup code 
right after things like curthread are initialized.  If dev_lock() is called 
before mutex_init() it can't work right anyway as mtx_init() doesn't work 
until then.

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