Re: Today Linus redesigns the networking driver interface (was Re: tulip driver in ...)

Doug Ledford (dledford@dialnet.net)
Mon, 21 Sep 1998 14:22:38 -0500


Leonard N. Zubkoff wrote:

> It's not just his driver either. In certain cases I've managed to clock over
> 13000 interrupts/second on a single host aapter, and multiple host adapters
> just magnify this.

I would venture to guess this was artificially generated load? I have yet
to see a real world situation generate anything like that simply because
real world situations don't generate a mountain of 512 byte or 1k requests.
They like to use larger block sizes if possible.

> The real issue with SA_INTERRUPT is not wanting unnecessary
> bottom half processing, not the slower interrupt trap entry/exit sequences. As
> has been suggested multiple times before, a reasonable way to get rid of
> SA_INTERRUPT is to allow interrupt handlers to return a value indicating
> whether they need bottom half processing or not, and OR together the results
> from all the interrupt handlers sharing an interrupt.

Or, as Alan pointed out, make your ISR routine return a non-void int value
to indicate bh yea or nay.

-- 

Doug Ledford <dledford@dialnet.net> Opinions expressed are my own, but they should be everybody's.

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