mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-30 16:13:54 +08:00
af55688435
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>
31 lines
653 B
C
31 lines
653 B
C
#ifndef _LINUX_AVERAGE_H
|
|
#define _LINUX_AVERAGE_H
|
|
|
|
/* 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;
|
|
}
|
|
|
|
#endif /* _LINUX_AVERAGE_H */
|