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To: Juergen Lock <nox@jelal.kn-bremen.de>
In-reply-to: Your message of "Sun, 12 Apr 2009 20:56:24 +0200."
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Comments: In-reply-to Juergen Lock <nox@jelal.kn-bremen.de>
	message dated "Sun, 12 Apr 2009 20:56:24 +0200."
Date: Sun, 12 Apr 2009 12:26:02 -0700
From: Bakul Shah <bakul@bitblocks.com>
Message-Id: <20090412192602.661B45B23@mail.bitblocks.com>
Cc: jtidwell <necanthrope@gmail.com>, freebsd-emulation@freebsd.org
Subject: Re: cannot get kqemu to load with kldload 
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On Sun, 12 Apr 2009 20:56:24 +0200 Juergen Lock <nox@jelal.kn-bremen.de>  wrote:
> On Sun, Apr 12, 2009 at 11:29:39AM -0700, Bakul Shah wrote:
> > 
> > But this brings up another problem with kqemu: if you are
> > using SCHED_4BSD with 7.x or current, kqemu is not guaranteed
> > to work.
> 
> Oh, so the code it then uses in kqemu_schedule() is ule only?
> Does the old scheduler still use sched_lock?
> 
>     [...]
>     struct thread *td = curthread;
>     thread_lock(td);
>     mi_switch(SW_VOL, NULL);
>     thread_unlock(td);
>     [...]

You'd have to ask a scheduling expert but it appears that
4BSD sticks sched_lock in thread lock so it should just work
(checked only in -current).  So I take back my complaint :-)