[mirror_ubuntu-bionic-kernel.git] / include / linux / ratelimit.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_RATELIMIT_H
#define _LINUX_RATELIMIT_H

#include <linux/param.h>
#include <linux/sched.h>
#include <linux/spinlock.h>

#define DEFAULT_RATELIMIT_INTERVAL	(5 * HZ)
#define DEFAULT_RATELIMIT_BURST		10

/* issue num suppressed message on exit */
#define RATELIMIT_MSG_ON_RELEASE	BIT(0)

struct ratelimit_state {
	raw_spinlock_t	lock;		/* protect the state */

	int		interval;
	int		burst;
	int		printed;
	int		missed;
	unsigned long	begin;
	unsigned long	flags;
};

#define RATELIMIT_STATE_INIT(name, interval_init, burst_init) {		\
		.lock		= __RAW_SPIN_LOCK_UNLOCKED(name.lock),	\
		.interval	= interval_init,			\
		.burst		= burst_init,				\
	}

#define RATELIMIT_STATE_INIT_DISABLED					\
	RATELIMIT_STATE_INIT(ratelimit_state, 0, DEFAULT_RATELIMIT_BURST)

#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init)		\
									\
	struct ratelimit_state name =					\
		RATELIMIT_STATE_INIT(name, interval_init, burst_init)	\

static inline void ratelimit_state_init(struct ratelimit_state *rs,
					int interval, int burst)
{
	memset(rs, 0, sizeof(*rs));

	raw_spin_lock_init(&rs->lock);
	rs->interval	= interval;
	rs->burst	= burst;
}

static inline void ratelimit_default_init(struct ratelimit_state *rs)
{
	return ratelimit_state_init(rs, DEFAULT_RATELIMIT_INTERVAL,
					DEFAULT_RATELIMIT_BURST);
}

static inline void ratelimit_state_exit(struct ratelimit_state *rs)
{
	if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE))
		return;

	if (rs->missed) {
		pr_warn("%s: %d output lines suppressed due to ratelimiting\n",
			current->comm, rs->missed);
		rs->missed = 0;
	}
}

static inline void
ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags)
{
	rs->flags = flags;
}

extern struct ratelimit_state printk_ratelimit_state;

extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
#define __ratelimit(state) ___ratelimit(state, __func__)

#ifdef CONFIG_PRINTK

#define WARN_ON_RATELIMIT(condition, state)	({		\
	bool __rtn_cond = !!(condition);			\
	WARN_ON(__rtn_cond && __ratelimit(state));		\
	__rtn_cond;						\
})

#define WARN_RATELIMIT(condition, format, ...)			\
({								\
	static DEFINE_RATELIMIT_STATE(_rs,			\
				      DEFAULT_RATELIMIT_INTERVAL,	\
				      DEFAULT_RATELIMIT_BURST);	\
	int rtn = !!(condition);				\
								\
	if (unlikely(rtn && __ratelimit(&_rs)))			\
		WARN(rtn, format, ##__VA_ARGS__);		\
								\
	rtn;							\
})

#else

#define WARN_ON_RATELIMIT(condition, state)			\
	WARN_ON(condition)

#define WARN_RATELIMIT(condition, format, ...)			\
({								\
	int rtn = WARN(condition, format, ##__VA_ARGS__);	\
	rtn;							\
})

#endif

#endif /* _LINUX_RATELIMIT_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
717115e1 DY	2	#ifndef _LINUX_RATELIMIT_H
717115e1 DY	3	#define _LINUX_RATELIMIT_H
979f693d	4
717115e1	5	#include <linux/param.h>
6b1d174b	6	#include <linux/sched.h>
f40c396a	7	#include <linux/spinlock.h>
717115e1	8
979f693d IM	9	#define DEFAULT_RATELIMIT_INTERVAL (5 * HZ)
979f693d IM	10	#define DEFAULT_RATELIMIT_BURST 10
717115e1	11
6b1d174b BP	12	/* issue num suppressed message on exit */
	13	#define RATELIMIT_MSG_ON_RELEASE BIT(0)
	14
717115e1	15	struct ratelimit_state {
07354eb1	16	raw_spinlock_t lock; /* protect the state */
979f693d IM	17
	18	int interval;
	19	int burst;
	20	int printed;
	21	int missed;
	22	unsigned long begin;
6b1d174b	23	unsigned long flags;
717115e1 DY	24	};
717115e1 DY	25
89e3f909	26	#define RATELIMIT_STATE_INIT(name, interval_init, burst_init) { \
07354eb1	27	.lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
979f693d IM	28	.interval = interval_init, \
	29	.burst = burst_init, \
	30	}
717115e1	31
89e3f909 DM	32	#define RATELIMIT_STATE_INIT_DISABLED \
	33	RATELIMIT_STATE_INIT(ratelimit_state, 0, DEFAULT_RATELIMIT_BURST)
	34
	35	#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init) \
	36	\
	37	struct ratelimit_state name = \
	38	RATELIMIT_STATE_INIT(name, interval_init, burst_init) \
	39
f40c396a OH	40	static inline void ratelimit_state_init(struct ratelimit_state *rs,
	41	int interval, int burst)
	42	{
6b1d174b BP	43	memset(rs, 0, sizeof(*rs));
6b1d174b BP	44
07354eb1	45	raw_spin_lock_init(&rs->lock);
6b1d174b BP	46	rs->interval = interval;
	47	rs->burst = burst;
	48	}
	49
	50	static inline void ratelimit_default_init(struct ratelimit_state *rs)
	51	{
	52	return ratelimit_state_init(rs, DEFAULT_RATELIMIT_INTERVAL,
	53	DEFAULT_RATELIMIT_BURST);
	54	}
	55
	56	static inline void ratelimit_state_exit(struct ratelimit_state *rs)
	57	{
	58	if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE))
	59	return;
	60
	61	if (rs->missed) {
	62	pr_warn("%s: %d output lines suppressed due to ratelimiting\n",
	63	current->comm, rs->missed);
	64	rs->missed = 0;
	65	}
	66	}
	67
	68	static inline void
	69	ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags)
	70	{
	71	rs->flags = flags;
f40c396a OH	72	}
f40c396a OH	73
f5d87d85 NK	74	extern struct ratelimit_state printk_ratelimit_state;
f5d87d85 NK	75
5c828713 CB	76	extern int ___ratelimit(struct ratelimit_state rs, const char func);
5c828713 CB	77	#define __ratelimit(state) ___ratelimit(state, __func__)
979f693d	78
86e4ca66 DM	79	#ifdef CONFIG_PRINTK
86e4ca66 DM	80
1b011e2f JS	81	#define WARN_ON_RATELIMIT(condition, state) ({ \
	82	bool __rtn_cond = !!(condition); \
	83	WARN_ON(__rtn_cond && __ratelimit(state)); \
	84	__rtn_cond; \
	85	})
86e4ca66	86
2351a6c6	87	#define WARN_RATELIMIT(condition, format, ...) \
86e4ca66 DM	88	({ \
	89	static DEFINE_RATELIMIT_STATE(_rs, \
	90	DEFAULT_RATELIMIT_INTERVAL, \
	91	DEFAULT_RATELIMIT_BURST); \
2351a6c6 MT	92	int rtn = !!(condition); \
	93	\
	94	if (unlikely(rtn && __ratelimit(&_rs))) \
	95	WARN(rtn, format, ##__VA_ARGS__); \
	96	\
	97	rtn; \
86e4ca66 DM	98	})
	99
	100	#else
	101
	102	#define WARN_ON_RATELIMIT(condition, state) \
	103	WARN_ON(condition)
	104
2351a6c6	105	#define WARN_RATELIMIT(condition, format, ...) \
86e4ca66	106	({ \
2351a6c6	107	int rtn = WARN(condition, format, ##__VA_ARGS__); \
86e4ca66 DM	108	rtn; \
	109	})
	110
	111	#endif
	112
979f693d	113	#endif /* _LINUX_RATELIMIT_H */