[linux-audio-dev] IRQ rotation

[Steve Harris]

Hi all,

This has been discussed briefly before:
http://www.music.columbia.edu/pipermail/linux-audio-user/2003-March/002834.html

It used to be possible (in the 2.0 kernel series) to the rotate priority of
IRQs on the two controllers. This sounds really good as on my laptop the
soundcard is welded to IRQ5 (very low priority) and everything else is on
IRQ10 (higher, c.f. http://myweb.cableone.net/eviltwin69/Arcana.html sec
2.4), so I can only run the card with big buffers.

The tool used to do the rotation was irqtune:
http://cae.best.vwh.net/irqtune/

I'm downloaded it, hacked it to work with 2.4, but it doesnt seem to do
anything (no errors, but no action either AFAICT). I'm wondering if somene
here knows enough about the kernel to have a clue why its not doing
anything. I can mail a patch to anyone whos interested, but as I said it
doesnt work at the moment.

I'm replacing this laptop soon, so its mostly academic interest, but it
might have been of use to someone.

Possibly something similar can be done with APIC, but it didn't seem to
work very well on this machine last time I tried.

- Steve