This is needed for the powernow k8 driver to manage AMD dual core systems. 
(see explanation in previous CMP patch for more details) 
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: <mark.langsdorf@amd.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>