5113f6f70
 김현기
kernel add
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
#ifndef _LINUX_AVERAGE_H
#define _LINUX_AVERAGE_H
/* Exponentially weighted moving average (EWMA) */
#define DECLARE_EWMA(name, _factor, _weight) \
struct ewma_##name { \
unsigned long internal; \
}; \
static inline void ewma_##name##_init(struct ewma_##name *e) \
{ \
BUILD_BUG_ON(!__builtin_constant_p(_factor)); \
BUILD_BUG_ON(!__builtin_constant_p(_weight)); \
BUILD_BUG_ON_NOT_POWER_OF_2(_factor); \
BUILD_BUG_ON_NOT_POWER_OF_2(_weight); \
e->internal = 0; \
} \
static inline unsigned long \
ewma_##name##_read(struct ewma_##name *e) \
{ \
BUILD_BUG_ON(!__builtin_constant_p(_factor)); \
BUILD_BUG_ON(!__builtin_constant_p(_weight)); \
BUILD_BUG_ON_NOT_POWER_OF_2(_factor); \
BUILD_BUG_ON_NOT_POWER_OF_2(_weight); \
return e->internal >> ilog2(_factor); \
} \
static inline void ewma_##name##_add(struct ewma_##name *e, \
unsigned long val) \
{ \
unsigned long internal = ACCESS_ONCE(e->internal); \
unsigned long weight = ilog2(_weight); \
unsigned long factor = ilog2(_factor); \
\
BUILD_BUG_ON(!__builtin_constant_p(_factor)); \
BUILD_BUG_ON(!__builtin_constant_p(_weight)); \
BUILD_BUG_ON_NOT_POWER_OF_2(_factor); \
BUILD_BUG_ON_NOT_POWER_OF_2(_weight); \
\
ACCESS_ONCE(e->internal) = internal ? \
(((internal << weight) - internal) + \
(val << factor)) >> weight : \
(val << factor); \
}
#endif /* _LINUX_AVERAGE_H */
|