Re: RT question : softirq and minimal user RT priority

From: Mark Hounschell
Date: Mon Apr 17 2006 - 09:21:53 EST


Steven Rostedt wrote:
>> Is the smallest usable real-time priority greater than the highest real-time softirq ?
>
> Nope, you can use any rt priority you want. It's up to you whether you
> want to preempt the softirqs or not. Be careful, timers may be preempted
> from delivering signals to high priority processes. I have a patch to
> fix this, but I'm waiting on input from either Thomas Gleixner or Ingo.
>
> -- Steve

I know this is an old thread but I seem to be having a problem similar
to this and I didn't find any real resolution in the archives.

I'm using the rt16 patch on 2.6.16.5 with complete preemption. I have a
high priority rt compute bound task that isn't getting signals from a
pci cards interrupt handler. Only when I insure the rt priority of the
task is lower than the rt priority of the irq thread ([IRQ 193]) will my
task receive signals.

Is this a bug? Is the bug in my interrupt handler? Or is this expected
and acceptable?

Thanks
Mark

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/