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From: Doug Rabson <dfr@nlsystems.com>
To: Alex Wilkinson <alex.wilkinson@dsto.defence.gov.au>
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Subject: Re: taskqueue patch
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On Mon, 2003-11-10 at 23:39, Alex Wilkinson wrote:
> 	On Mon, Nov 10, 2003 at 09:02:03AM +0000, Doug Rabson wrote:
> 
> 	I wasn't involved in converting taskqueue from 4.x-style SWIs to kernel
> 	threads so I can't be sure but this does look reasonable. I've been
> 	wondering about the 'not exiting' diagnostic from init for a while
> 	myself.
> 
> Hi Doug,
> 
> What are "SWIs" ?

Its an ancient VAX concept - 'SoftWare Interrupts'. Basically on a vax,
you could poke a register and it would cause a low-priority interrupt.
They were often used for 'split priority' interrupt handlers where you
did the minimum amount of work in the first interrupt and then triggered
a SWI for the rest. The advantage being that the SWI could be pre-empted
by another high-priority hardware interrupt.