[PATCH] Use uname not sysctl to get the kernel revision

[H. Peter Anvin]

Arjan van de Ven wrote:
>> It is a short busy wait before falling asleep.  I assume you mean
>> busy wait is a loss even on SMP?
> 
> eh yeah I forgot to think for a second. But yes even for SMP busy wait
> is pretty bad power wise nowadays.. at least if you wait more than a few
> hundred cycles. (and if you wait less... then it's almost unlikely that
> it'll be useful as well)
> 

It depends greatly; if a lock is likely to get released by the user 
after a few memory accesses, spinning is likely to be a win.

	-hpa