This gives a small but measureable performance improvement for
I/O heavy workloads.
(From OE-Core rev: e4bd65e68c3d0dd798ff69c2e9491e5b2dcafdc3)
Signed-off-by: Phil Blundell <pb@pbcl.net>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>