Re: Why no interrupt priorities?

Richard B. Johnson
2004-02-27T13:21:34Z

On Thu, 26 Feb 2004, Tim Bird wrote:

> Richard B. Johnson wrote:
> > On Thu, 26 Feb 2004, Tim Bird wrote:
> >
> >>What's the rationale for not supporting interrupt priorities
> >>in the kernel?
> >
> > Interrupt priorities are supported and have been supported
> > since the first cascaded interrupt controllers and, now
> > with the APIC.
>
> Please forgive my ignorance. I'm not sure what's going
> on with 2.6 and work queues, but do the hardware priorities
> allow you to control scheduling of interrupt bottom halves?
>

Only to the extent that the bottom halves will naturally
occur after the hardware interrupt. There is no explicit
"hold execution until something else is done" in the queue.

It is a queue, i.e., one task after another.

> =============================
> Tim Bird
> Architecture Group Co-Chair
> CE Linux Forum
> Senior Staff Engineer
> Sony Electronics
> E-mail: Tim.Bird@am.sony.com
> =============================
>

Cheers,
Dick Johnson
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