> > everywhere will just trash performance. They are pure hardware interactions
> > so you can't automatically detect them.
>
> Why should spin locks trash perfomance, while an expensive disable_irq()
> doesn't?
disable_irq only blocks _one_ interrupt line, spin_lock_irqsave locks the
interrupt off on a uniprocessor, and 50% of the time off on a
dual processor.
If I use a spin lock you can't run a modem and an NE2000 card together on
Linux 2.4. Thats why I had to do that work on the code. Its one of myriads
of basic obvious cases that the pre-empt patch gets wrong
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This archive was generated by hypermail 2b29 : Tue Jan 15 2002 - 21:00:40 EST