Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1#ifndef _LINUX_RATELIMIT_H
2#define _LINUX_RATELIMIT_H
3
4#include <linux/param.h>
5#include <linux/sched.h>
6#include <linux/spinlock.h>
7
8#define DEFAULT_RATELIMIT_INTERVAL (5 * HZ)
9#define DEFAULT_RATELIMIT_BURST 10
10
11/* issue num suppressed message on exit */
12#define RATELIMIT_MSG_ON_RELEASE BIT(0)
13
14struct ratelimit_state {
15 raw_spinlock_t lock; /* protect the state */
16
17 int interval;
18 int burst;
19 int printed;
20 int missed;
21 unsigned long begin;
22 unsigned long flags;
23};
24
25#define RATELIMIT_STATE_INIT(name, interval_init, burst_init) { \
26 .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
27 .interval = interval_init, \
28 .burst = burst_init, \
29 }
30
31#define RATELIMIT_STATE_INIT_DISABLED \
32 RATELIMIT_STATE_INIT(ratelimit_state, 0, DEFAULT_RATELIMIT_BURST)
33
34#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init) \
35 \
36 struct ratelimit_state name = \
37 RATELIMIT_STATE_INIT(name, interval_init, burst_init) \
38
39static inline void ratelimit_state_init(struct ratelimit_state *rs,
40 int interval, int burst)
41{
42 memset(rs, 0, sizeof(*rs));
43
44 raw_spin_lock_init(&rs->lock);
45 rs->interval = interval;
46 rs->burst = burst;
47}
48
49static inline void ratelimit_default_init(struct ratelimit_state *rs)
50{
51 return ratelimit_state_init(rs, DEFAULT_RATELIMIT_INTERVAL,
52 DEFAULT_RATELIMIT_BURST);
53}
54
55static inline void ratelimit_state_exit(struct ratelimit_state *rs)
56{
57 if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE))
58 return;
59
60 if (rs->missed) {
61 pr_warn("%s: %d output lines suppressed due to ratelimiting\n",
62 current->comm, rs->missed);
63 rs->missed = 0;
64 }
65}
66
67static inline void
68ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags)
69{
70 rs->flags = flags;
71}
72
73extern struct ratelimit_state printk_ratelimit_state;
74
75extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
76#define __ratelimit(state) ___ratelimit(state, __func__)
77
78#ifdef CONFIG_PRINTK
79
80#define WARN_ON_RATELIMIT(condition, state) \
81 WARN_ON((condition) && __ratelimit(state))
82
83#define WARN_RATELIMIT(condition, format, ...) \
84({ \
85 static DEFINE_RATELIMIT_STATE(_rs, \
86 DEFAULT_RATELIMIT_INTERVAL, \
87 DEFAULT_RATELIMIT_BURST); \
88 int rtn = !!(condition); \
89 \
90 if (unlikely(rtn && __ratelimit(&_rs))) \
91 WARN(rtn, format, ##__VA_ARGS__); \
92 \
93 rtn; \
94})
95
96#else
97
98#define WARN_ON_RATELIMIT(condition, state) \
99 WARN_ON(condition)
100
101#define WARN_RATELIMIT(condition, format, ...) \
102({ \
103 int rtn = WARN(condition, format, ##__VA_ARGS__); \
104 rtn; \
105})
106
107#endif
108
109#endif /* _LINUX_RATELIMIT_H */