From 8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Tue, 15 Dec 2015 14:52:16 -0300 Subject: Linux-libre 4.3.2-gnu --- lib/average.c | 64 ----------------------------------------------------------- 1 file changed, 64 deletions(-) delete mode 100644 lib/average.c (limited to 'lib/average.c') diff --git a/lib/average.c b/lib/average.c deleted file mode 100644 index 114d1beae..000000000 --- a/lib/average.c +++ /dev/null @@ -1,64 +0,0 @@ -/* - * lib/average.c - * - * This source code is licensed under the GNU General Public License, - * Version 2. See the file COPYING for more details. - */ - -#include -#include -#include -#include -#include - -/** - * DOC: Exponentially Weighted Moving Average (EWMA) - * - * These are generic functions for calculating Exponentially Weighted Moving - * Averages (EWMA). We keep a structure with the EWMA parameters and a scaled - * up internal representation of the average value to prevent rounding errors. - * The factor for scaling up and the exponential weight (or decay rate) have to - * be specified thru the init fuction. The structure should not be accessed - * directly but only thru the helper functions. - */ - -/** - * ewma_init() - Initialize EWMA parameters - * @avg: Average structure - * @factor: Factor to use for the scaled up internal value. The maximum value - * of averages can be ULONG_MAX/(factor*weight). For performance reasons - * factor has to be a power of 2. - * @weight: Exponential weight, or decay rate. This defines how fast the - * influence of older values decreases. For performance reasons weight has - * to be a power of 2. - * - * Initialize the EWMA parameters for a given struct ewma @avg. - */ -void ewma_init(struct ewma *avg, unsigned long factor, unsigned long weight) -{ - WARN_ON(!is_power_of_2(weight) || !is_power_of_2(factor)); - - avg->weight = ilog2(weight); - avg->factor = ilog2(factor); - avg->internal = 0; -} -EXPORT_SYMBOL(ewma_init); - -/** - * ewma_add() - Exponentially weighted moving average (EWMA) - * @avg: Average structure - * @val: Current value - * - * Add a sample to the average. - */ -struct ewma *ewma_add(struct ewma *avg, unsigned long val) -{ - unsigned long internal = ACCESS_ONCE(avg->internal); - - ACCESS_ONCE(avg->internal) = internal ? - (((internal << avg->weight) - internal) + - (val << avg->factor)) >> avg->weight : - (val << avg->factor); - return avg; -} -EXPORT_SYMBOL(ewma_add); -- cgit v1.2.3-54-g00ecf