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 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, format, ...) \ 50 ({ \ 51 static DEFINE_RATELIMIT_STATE(_rs, \ 52 DEFAULT_RATELIMIT_INTERVAL, \ 53 DEFAULT_RATELIMIT_BURST); \ 54 int rtn = !!(condition); \ 55 \ 56 if (unlikely(rtn && __ratelimit(&_rs))) \ 57 WARN(rtn, format, ##__VA_ARGS__); \ 58 \ 59 rtn; \ 60 }) 61 62 #else 63 64 #define WARN_ON_RATELIMIT(condition, state) \ 65 WARN_ON(condition) 66 67 #define WARN_RATELIMIT(condition, format, ...) \ 68 ({ \ 69 int rtn = WARN(condition, format, ##__VA_ARGS__); \ 70 rtn; \ 71 }) 72 73 #endif 74 75 #endif /* _LINUX_RATELIMIT_H */ 76