diff options
| -rw-r--r-- | include/linux/average.h | 24 | ||||
| -rw-r--r-- | lib/Kconfig | 10 | ||||
| -rw-r--r-- | lib/average.c | 64 |
3 files changed, 0 insertions, 98 deletions
diff --git a/include/linux/average.h b/include/linux/average.h index 60f8226c5652..d04aa58280de 100644 --- a/include/linux/average.h +++ b/include/linux/average.h @@ -3,30 +3,6 @@ /* Exponentially weighted moving average (EWMA) */ -/* For more documentation see lib/average.c */ - -struct ewma { - unsigned long internal; - unsigned long factor; - unsigned long weight; -}; - -extern void ewma_init(struct ewma *avg, unsigned long factor, - unsigned long weight); - -extern struct ewma *ewma_add(struct ewma *avg, unsigned long val); - -/** - * ewma_read() - Get average value - * @avg: Average structure - * - * Returns the average value held in @avg. - */ -static inline unsigned long ewma_read(const struct ewma *avg) -{ - return avg->internal >> avg->factor; -} - #define DECLARE_EWMA(name, _factor, _weight) \ struct ewma_##name { \ unsigned long internal; \ diff --git a/lib/Kconfig b/lib/Kconfig index 3a2ef67db6c7..278890dd1049 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -460,16 +460,6 @@ config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE config LRU_CACHE tristate -config AVERAGE - bool "Averaging functions" - help - This option is provided for the case where no in-kernel-tree - modules require averaging functions, but a module built outside - the kernel tree does. Such modules that use library averaging - functions require Y here. - - If unsure, say N. - config CLZ_TAB bool diff --git a/lib/average.c b/lib/average.c deleted file mode 100644 index 114d1beae0c7..000000000000 --- 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 <linux/export.h> -#include <linux/average.h> -#include <linux/kernel.h> -#include <linux/bug.h> -#include <linux/log2.h> - -/** - * 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); |