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Date: Mon, 25 Aug 2003 23:36:34 -0600
From: "Kenneth D. Merry" <ken@kdm.org>
To: Nate Lawson <nate@root.org>
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cc: stable@freebsd.org
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Subject: Re: scsi-da does not work with INVARIANTS (fwd)
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On Mon, Aug 25, 2003 at 18:29:49 -0600, Kenneth D. Merry wrote:
> On Mon, Aug 25, 2003 at 13:49:30 -0700, Nate Lawson wrote:
> > Ken is aware of the following problem.  It is in both cd(4) and da(4) as
> > well as stable and current.  One possible approach would be to run
> > {da,cd}register() from a task queue and not at interrupt time.
> 
> That would be tricky, since the peripheral registration process currently
> expects a success/failure return from the peripheral constructor.
> 
> Just putting the sysctl creation in a task queue, though, would not be too
> difficult.
> 
> One question I have, though, is whether task queues run in a thread context
> or not.  If not, then we'll have the same problem.

The answer is -- the currently defined task queues use software
interrupts.

If it is possible to create a task queue that uses a kernel thread instead,
that might be a generally useful thing.  (And it might solve this
particular issue.)

Ken
-- 
Kenneth Merry
ken@kdm.org