1 #ifndef _LINUX_RATELIMIT_H
2 #define _LINUX_RATELIMIT_H
3
4 #include <linux/param.h>
5 #include <linux/spinlock.h>
6
7 #define DEFAULT_RATELIMIT_INTERVAL (5 * HZ)
8 #define DEFAULT_RATELIMIT_BURST 10
9
10 struct ratelimit_state {
11 raw_spinlock_t lock; /* protect the state */
12
13 int interval;
14 int burst;
15 int printed;
16 int missed;
17 unsigned long begin;
18 };
19
20 #define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init) \
21 \
22 struct ratelimit_state name = { \
23 .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
24 .interval = interval_init, \
25 .burst = burst_init, \
26 }
27
ratelimit_state_init(struct ratelimit_state * rs,int interval,int burst)28 static inline void ratelimit_state_init(struct ratelimit_state *rs,
29 int interval, int burst)
30 {
31 raw_spin_lock_init(&rs->lock);
32 rs->interval = interval;
33 rs->burst = burst;
34 rs->printed = 0;
35 rs->missed = 0;
36 rs->begin = 0;
37 }
38
39 extern struct ratelimit_state printk_ratelimit_state;
40
41 extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
42 #define __ratelimit(state) ___ratelimit(state, __func__)
43
44 #ifdef CONFIG_PRINTK
45
46 #define WARN_ON_RATELIMIT(condition, state) \
47 WARN_ON((condition) && __ratelimit(state))
48
49 #define __WARN_RATELIMIT(condition, state, format...) \
50 ({ \
51 int rtn = 0; \
52 if (unlikely(__ratelimit(state))) \
53 rtn = WARN(condition, format); \
54 rtn; \
55 })
56
57 #define WARN_RATELIMIT(condition, format...) \
58 ({ \
59 static DEFINE_RATELIMIT_STATE(_rs, \
60 DEFAULT_RATELIMIT_INTERVAL, \
61 DEFAULT_RATELIMIT_BURST); \
62 __WARN_RATELIMIT(condition, &_rs, format); \
63 })
64
65 #else
66
67 #define WARN_ON_RATELIMIT(condition, state) \
68 WARN_ON(condition)
69
70 #define __WARN_RATELIMIT(condition, state, format...) \
71 ({ \
72 int rtn = WARN(condition, format); \
73 rtn; \
74 })
75
76 #define WARN_RATELIMIT(condition, format...) \
77 ({ \
78 int rtn = WARN(condition, format); \
79 rtn; \
80 })
81
82 #endif
83
84 #endif /* _LINUX_RATELIMIT_H */
85