lib: Improve EWMA efficiency by using bitshifts
authorBruno Randolf <br1@einfach.org>
Thu, 2 Dec 2010 10:50:37 +0000 (19:50 +0900)
committerJohn W. Linville <linville@tuxdriver.com>
Mon, 6 Dec 2010 20:58:43 +0000 (15:58 -0500)
commitaf5568843594fb71055debe36e521fa8072fcecc
tree4f35966cb4e1018b05c87d7a10c337d888949e22
parent5dcc03fe29537edd7819f5b121bf3d779693f37b
lib: Improve EWMA efficiency by using bitshifts

Using bitshifts instead of division and multiplication should improve
performance. That requires weight and factor to be powers of two, but i think
this is something we can live with.

Thanks to Peter Zijlstra for the improved formula!

Signed-off-by: Bruno Randolf <br1@einfach.org>
--

v2: use log2.h functions
Signed-off-by: John W. Linville <linville@tuxdriver.com>
include/linux/average.h
lib/average.c