Very Computer

Trying to use soft interrupts to service highlevel interrupts on a SPARC LX
under Solaris 2.3 I have two problems:

1) As I have to handle two highlevel interrupts, I need also two different
soft interrupt handlers. But triggering one soft interrupt handler triggers
the other one too, no matter which soft interrupt identifier is passed in
ddi_trigger_softintr.

2) If DDI_SOFTINT_HIGH is used as preference in ddi_add_softintr the
soft interrupt handler goes berzerk. Even without any trigger call existing
in the whole source, the handler is called on and on. The system is busy
running the soft interrupt handler and has to be switched off.

Is there anyone familiar with such stuff?

Thanks in advance,
Roman

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You can do it with a single soft interrupt. Your data structure should be
used for both highlevel routines and be protected with the same mutex.
Leave a flag for the soft interrupt handler to know which interrupt to
serve.
If you want to use two different soft interrupts, each must examine the
flag and return DDI_INTR_UNCLAIMED if it is not its task.
As with hardware interrupts (of the same level), all software interrupts
are served from the OS one by one, until someone DDI_CLAIMs it.

Quote:>2) If DDI_SOFTINT_HIGH is used as preference in ddi_add_softintr the
>soft interrupt handler goes berzerk. Even without any trigger call existing
>in the whole source, the handler is called on and on. The system is busy
>running the soft interrupt handler and has to be switched off.

Are you sure your interrupt handler returns DDI_INTR_CLAIMED? Or, even
more likely, does your handler ALWAYS return  --"-- ?
Then I suppose another soft interrupt can not be served, and the corre-
lating hardware interrupt triggers it on and on and on and on and....

Ingo
--
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