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Date: Wed, 14 Jun 2006 20:52:05 +0000
From: John Birrell <jb@what-creek.com>
To: John Baldwin <jhb@freebsd.org>
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Cc: perforce@freebsd.org
Subject: Re: PERFORCE change 99099 for review
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On Tue, Jun 13, 2006 at 09:30:46AM -0400, John Baldwin wrote:
> On Monday 12 June 2006 20:47, John Birrell wrote:
> > http://perforce.freebsd.org/chv.cgi?CH=99099
> > 
> > Change 99099 by jb@jb_freebsd2 on 2006/06/13 00:47:28
> > 
> > 	Add hooks for DTrace to register a function to be called when
> > 	the scheduler chooses a new thread to run. This is required for
> > 	DTrace vtime.
> 
> You should probably do this in mi_switch() in kern_synch.c rather than
> in this macro.

Looking further at this is seems that the code actually has to be
inserted into each scheduler just before the call to cpu_switch because
the schedulers are each capable of selecting a new thread right up
to that time (see sched_switch).

--
John Birrell