|  | #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 */ |