From: Manfred Spraul <manfred@colorfullife.com>

Reversing the patches that made all caches hw cacheline aligned had an
unintended side effect on the kmalloc caches: Before they had the
SLAB_HWCACHE_ALIGN flag set, now it's clear.  This breaks one sgi driver -
it expects aligned caches.  Additionally I think it's the right thing to
do: It costs virtually nothing (the caches are power-of-two sized) and
could reduce false sharing.

Additionally, the patch adds back the documentation for the
SLAB_HWCACHE_ALIGN flag.

Signed-Off: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>