Re: [PATCH -mm 1/5] Blackfin: blackfin architecture patch update

From: Arnd Bergmann
Date: Sat Mar 03 2007 - 18:05:54 EST


On Saturday 03 March 2007 23:50:02 bert hubert wrote:
> >       for (;;)
> >               asm volatile ("idle");
>
> This looks remarkably like relax_cpu()

Actually not: cpu_relax() is defined as barrier(), it can't
call idle because that might make it sleep for a indefinite
amount of time (until the next interrupt, but only if they
are enabled).

Some nice architectures provide a hardware mechanism to do
cpu_relax, like going to low-power mode for a few microseconds,
but this one doesn't seem to have it.

Arnd <><
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