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Date: Fri, 3 Sep 2004 12:26:13 +1200
From: Juha Saarinen <juhasaarinen@gmail.com>
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Subject: DEVICE_POLLING on Intel HT systems
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I tried recompiling the kernel on a 5.3-beta2 box with DEVICE_POLLING
enabled. Compilation failed with a message saying DEVICE_POLLING isn't
compatible with SMP.

Luigi says on:

http://info.iet.unipi.it/~luigi/polling/

"Why does this code not work with SMP ?

It actually might work (if you remove a one line in systm.h which
prevents compilation with SMP). However, you would have a single
thread doing the polling, whereas an SMP box might in principle handle
concurrently interrupts from different devices.

I guess the best answer is that I am not yet sure on whether or not it
makes sense to have polling with SMP. "

The box in question is a "pseudo SMP" system, with an Intel
HyperThreaded P4 and with the fxp onboard the D850MV motherboard.

Has anyone hacked systm.h as per above and enabled DEVICE_POLLING on
an HT system? If so, did things compile and generally, work?

-- 

Juha