On Wed, 22 Jul 2009, Peter Zijlstra wrote:

On Wed, 2009-07-22 at 14:58 +0200, Thomas Gleixner wrote:

quoted

Thinking further we should even provide some infrastructure for that
in the common code which would handle the completion and attach it to
the interrupts in question, so the driver authors would not have to
deal with that at all. They just would return from thread_fn and let
the generic code deal with the notification. The notification has to
be set up by the interrupt controller code. That way you can use the
same device driver code w/o knowledge of the interrupt controller
implementation it is attached to.

Wouldn't it be better if we could express the nesting property from
within genirq, so that we can do things like:

  register_chip_nested(parent_chip, parent_irq, slave_chip);

And let genirq set-up the needed magic to make the nesting work.

Good point. 
 

Also, how important is it that subhandler1..n run in their own thread?
That is, can't we let them run from the thread that is otherwise waiting
for the completino anyway?

In those cases I suspect we can do that. I guess there can be async
handling as well: the main handler queries the pending interrupts,
masks them, wakes the handlers and returns. No wait for all threads to
finish necessary before unmasking the main interrupt line.

Thanks,

	tglx