The eCos, QNX, ChorusOs irq handling API

Valette Eric eric.valette at
Thu Feb 20 22:55:12 UTC 2003

Till Straumann wrote:
> Well - when you have multiple CPUs sharing one PIC, your approach
> of handling the masks doesn't work anyways, even if the ISR is forbidden 
> to touch the mask.

I know :-) I just wanted to point out that the whole sequence should be 
looked on SMP if using straight UMP code implementation. I not even 100% 
certain is can be done correctly.

BTW, on SMP, linux code use APIC and not the old 8259 model. I think I 
will do some investigation on linux code just for fun :-)

> But all of these are not really API issues but implementation
> details...

Maybe, maybe not. But as you seems to agree to hide the PIC manipulation 
who cares :-) But for sure, I would rather not let the average user code 
it :-)

-- eric

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