> > just removing the if() and the explicit IRQ enabling already makes irqs no longer nest...
quoted text
> 
> I can see why that would raise eyebrows. I can see getting bashed
> mercilessly with interrupt latency concerns as a result here. Can you
> suggest any defenses?


hardirq handlers are supposed to be fast. If they're slow the code
should (and generally is) using bottom halves/tasklets/softirqs. Combine
this with the fact that each new irq handler will start with a bunch of
cache misses, the latency added isn't generally that significant. In
addition, the cache miss thing makes the nesting suck a lot, it's faster
to batch the irqs in sequence.

-- 
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