1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_RATELIMIT_H
3 #define _LINUX_RATELIMIT_H
5 #include <linux/param.h>
6 #include <linux/sched.h>
7 #include <linux/spinlock.h>
9 #define DEFAULT_RATELIMIT_INTERVAL (5 * HZ)
10 #define DEFAULT_RATELIMIT_BURST 10
12 /* issue num suppressed message on exit */
13 #define RATELIMIT_MSG_ON_RELEASE BIT(0)
15 struct ratelimit_state {
16 raw_spinlock_t lock; /* protect the state */
26 #define RATELIMIT_STATE_INIT_FLAGS(name, interval_init, burst_init, flags_init) { \
27 .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
28 .interval = interval_init, \
29 .burst = burst_init, \
30 .flags = flags_init, \
33 #define RATELIMIT_STATE_INIT(name, interval_init, burst_init) \
34 RATELIMIT_STATE_INIT_FLAGS(name, interval_init, burst_init, 0)
36 #define RATELIMIT_STATE_INIT_DISABLED \
37 RATELIMIT_STATE_INIT(ratelimit_state, 0, DEFAULT_RATELIMIT_BURST)
39 #define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init) \
41 struct ratelimit_state name = \
42 RATELIMIT_STATE_INIT(name, interval_init, burst_init) \
44 static inline void ratelimit_state_init(struct ratelimit_state *rs,
45 int interval, int burst)
47 memset(rs, 0, sizeof(*rs));
49 raw_spin_lock_init(&rs->lock);
50 rs->interval = interval;
54 static inline void ratelimit_default_init(struct ratelimit_state *rs)
56 return ratelimit_state_init(rs, DEFAULT_RATELIMIT_INTERVAL,
57 DEFAULT_RATELIMIT_BURST);
60 static inline void ratelimit_state_exit(struct ratelimit_state *rs)
62 if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE))
66 pr_warn("%s: %d output lines suppressed due to ratelimiting\n",
67 current->comm, rs->missed);
73 ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags)
78 extern struct ratelimit_state printk_ratelimit_state;
80 extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
81 #define __ratelimit(state) ___ratelimit(state, __func__)
85 #define WARN_ON_RATELIMIT(condition, state) ({ \
86 bool __rtn_cond = !!(condition); \
87 WARN_ON(__rtn_cond && __ratelimit(state)); \
91 #define WARN_RATELIMIT(condition, format, ...) \
93 static DEFINE_RATELIMIT_STATE(_rs, \
94 DEFAULT_RATELIMIT_INTERVAL, \
95 DEFAULT_RATELIMIT_BURST); \
96 int rtn = !!(condition); \
98 if (unlikely(rtn && __ratelimit(&_rs))) \
99 WARN(rtn, format, ##__VA_ARGS__); \
106 #define WARN_ON_RATELIMIT(condition, state) \
109 #define WARN_RATELIMIT(condition, format, ...) \
111 int rtn = WARN(condition, format, ##__VA_ARGS__); \
117 #endif /* _LINUX_RATELIMIT_H */