LXR linux/include/linux/ratelimit.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_RATELIMIT_H
   3#define _LINUX_RATELIMIT_H
   4
   5#include <linux/ratelimit_types.h>
   6#include <linux/sched.h>
   7#include <linux/spinlock.h>
   8
   9static inline void ratelimit_state_init(struct ratelimit_state *rs,
  10                                        int interval, int burst)
  11{
  12        memset(rs, 0, sizeof(*rs));
  13
  14        raw_spin_lock_init(&rs->lock);
  15        rs->interval    = interval;
  16        rs->burst       = burst;
  17}
  18
  19static inline void ratelimit_default_init(struct ratelimit_state *rs)
  20{
  21        return ratelimit_state_init(rs, DEFAULT_RATELIMIT_INTERVAL,
  22                                        DEFAULT_RATELIMIT_BURST);
  23}
  24
  25static inline void ratelimit_state_exit(struct ratelimit_state *rs)
  26{
  27        if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE))
  28                return;
  29
  30        if (rs->missed) {
  31                pr_warn("%s: %d output lines suppressed due to ratelimiting\n",
  32                        current->comm, rs->missed);
  33                rs->missed = 0;
  34        }
  35}
  36
  37static inline void
  38ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags)
  39{
  40        rs->flags = flags;
  41}
  42
  43extern struct ratelimit_state printk_ratelimit_state;
  44
  45#ifdef CONFIG_PRINTK
  46
  47#define WARN_ON_RATELIMIT(condition, state)     ({              \
  48        bool __rtn_cond = !!(condition);                        \
  49        WARN_ON(__rtn_cond && __ratelimit(state));              \
  50        __rtn_cond;                                             \
  51})
  52
  53#define WARN_RATELIMIT(condition, format, ...)                  \
  54({                                                              \
  55        static DEFINE_RATELIMIT_STATE(_rs,                      \
  56                                      DEFAULT_RATELIMIT_INTERVAL,       \
  57                                      DEFAULT_RATELIMIT_BURST); \
  58        int rtn = !!(condition);                                \
  59                                                                \
  60        if (unlikely(rtn && __ratelimit(&_rs)))                 \
  61                WARN(rtn, format, ##__VA_ARGS__);               \
  62                                                                \
  63        rtn;                                                    \
  64})
  65
  66#else
  67
  68#define WARN_ON_RATELIMIT(condition, state)                     \
  69        WARN_ON(condition)
  70
  71#define WARN_RATELIMIT(condition, format, ...)                  \
  72({                                                              \
  73        int rtn = WARN(condition, format, ##__VA_ARGS__);       \
  74        rtn;                                                    \
  75})
  76
  77#endif
  78
  79#endif /* _LINUX_RATELIMIT_H */
  80