DEVICE_POLLING on Intel HT systems
Juha Saarinen
juhasaarinen at gmail.com
Thu Sep 2 17:26:18 PDT 2004
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
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