On Wed, 25 Apr 2007 11:48:45 +1000 Paul Mackerras <[EMAIL PROTECTED]> wrote:

> [EMAIL PROTECTED] writes:
> 
> > Avoid reevaluating smp_processor_id()
> 
> >     int this_cpu = smp_processor_id();
> > -   unsigned long touch_timestamp = __get_cpu_var(touch_timestamp);
> > +   unsigned long touch_timestamp = per_cpu(touch_timestamp, this_cpu);
> 
> This is actually worse on those cpus that have a fast way to get to
> the current cpu's per-cpu data.
> 

The patch adds 4 bytes (strange number) to powerpc text and removes 32 from
i386's.  A net win, I guess.

i386 now has a considerably better smp_processor_id(), but no special-case
handling of per-cpu data.  Maybe Jeremy has plans to move i386's per-cpu
data into the pda also?

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