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
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
/*
* FLoating proportions
*
* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
*
* This file contains the public data structure and API definitions.
*/
#ifndef _LINUX_PROPORTIONS_H
#define _LINUX_PROPORTIONS_H
#include <linux/percpu_counter.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
struct prop_global {
/*
* The period over which we differentiate
*
* period = 2^shift
*/
int shift;
/*
* The total event counter aka 'time'.
*
* Treated as an unsigned long; the lower 'shift - 1' bits are the
* counter bits, the remaining upper bits the period counter.
*/
struct percpu_counter events;
};
/*
* global proportion descriptor
*
* this is needed to consitently flip prop_global structures.
*/
struct prop_descriptor {
int index;
struct prop_global pg[2];
struct mutex mutex; /* serialize the prop_global switch */
};
int prop_descriptor_init(struct prop_descriptor *pd, int shift);
void prop_change_shift(struct prop_descriptor *pd, int new_shift);
/*
* ----- PERCPU ------
*/
struct prop_local_percpu {
/*
* the local events counter
*/
struct percpu_counter events;
/*
* snapshot of the last seen global state
*/
int shift;
unsigned long period;
spinlock_t lock; /* protect the snapshot state */
};
int prop_local_init_percpu(struct prop_local_percpu *pl);
void prop_local_destroy_percpu(struct prop_local_percpu *pl);
void __prop_inc_percpu(struct prop_descriptor *pd, struct prop_local_percpu *pl);
void prop_fraction_percpu(struct prop_descriptor *pd, struct prop_local_percpu *pl,
long *numerator, long *denominator);
static inline
void prop_inc_percpu(struct prop_descriptor *pd, struct prop_local_percpu *pl)
{
unsigned long flags;
local_irq_save(flags);
__prop_inc_percpu(pd, pl);
local_irq_restore(flags);
}
/*
* ----- SINGLE ------
*/
struct prop_local_single {
/*
* the local events counter
*/
unsigned long events;
/*
* snapshot of the last seen global state
* and a lock protecting this state
*/
int shift;
unsigned long period;
spinlock_t lock; /* protect the snapshot state */
};
#define INIT_PROP_LOCAL_SINGLE(name) \
{ .lock = __SPIN_LOCK_UNLOCKED(name.lock), \
}
int prop_local_init_single(struct prop_local_single *pl);
void prop_local_destroy_single(struct prop_local_single *pl);
void __prop_inc_single(struct prop_descriptor *pd, struct prop_local_single *pl);
void prop_fraction_single(struct prop_descriptor *pd, struct prop_local_single *pl,
long *numerator, long *denominator);
static inline
void prop_inc_single(struct prop_descriptor *pd, struct prop_local_single *pl)
{
unsigned long flags;
local_irq_save(flags);
__prop_inc_single(pd, pl);
local_irq_restore(flags);
}
#endif /* _LINUX_PROPORTIONS_H */
|
