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

#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
717115e1 DY	1	#ifndef _LINUX_RATELIMIT_H
717115e1 DY	2	#define _LINUX_RATELIMIT_H
979f693d	3
717115e1	4	#include <linux/param.h>
6b1d174b	5	#include <linux/sched.h>
f40c396a	6	#include <linux/spinlock.h>
717115e1	7
979f693d IM	8	#define DEFAULT_RATELIMIT_INTERVAL (5 * HZ)
979f693d IM	9	#define DEFAULT_RATELIMIT_BURST 10
717115e1	10
6b1d174b BP	11	/* issue num suppressed message on exit */
	12	#define RATELIMIT_MSG_ON_RELEASE BIT(0)
	13
717115e1	14	struct ratelimit_state {
07354eb1	15	raw_spinlock_t lock; /* protect the state */
979f693d IM	16
	17	int interval;
	18	int burst;
	19	int printed;
	20	int missed;
	21	unsigned long begin;
6b1d174b	22	unsigned long flags;
717115e1 DY	23	};
717115e1 DY	24
89e3f909	25	#define RATELIMIT_STATE_INIT(name, interval_init, burst_init) { \
07354eb1	26	.lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
979f693d IM	27	.interval = interval_init, \
	28	.burst = burst_init, \
	29	}
717115e1	30
89e3f909 DM	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
f40c396a OH	39	static inline void ratelimit_state_init(struct ratelimit_state *rs,
	40	int interval, int burst)
	41	{
6b1d174b BP	42	memset(rs, 0, sizeof(*rs));
6b1d174b BP	43
07354eb1	44	raw_spin_lock_init(&rs->lock);
6b1d174b BP	45	rs->interval = interval;
	46	rs->burst = burst;
	47	}
	48
	49	static 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
	55	static 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
	67	static inline void
	68	ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags)
	69	{
	70	rs->flags = flags;
f40c396a OH	71	}
f40c396a OH	72
f5d87d85 NK	73	extern struct ratelimit_state printk_ratelimit_state;
f5d87d85 NK	74
5c828713 CB	75	extern int ___ratelimit(struct ratelimit_state rs, const char func);
5c828713 CB	76	#define __ratelimit(state) ___ratelimit(state, __func__)
979f693d	77
86e4ca66 DM	78	#ifdef CONFIG_PRINTK
86e4ca66 DM	79
1b011e2f JS	80	#define WARN_ON_RATELIMIT(condition, state) ({ \
	81	bool __rtn_cond = !!(condition); \
	82	WARN_ON(__rtn_cond && __ratelimit(state)); \
	83	__rtn_cond; \
	84	})
86e4ca66	85
2351a6c6	86	#define WARN_RATELIMIT(condition, format, ...) \
86e4ca66 DM	87	({ \
	88	static DEFINE_RATELIMIT_STATE(_rs, \
	89	DEFAULT_RATELIMIT_INTERVAL, \
	90	DEFAULT_RATELIMIT_BURST); \
2351a6c6 MT	91	int rtn = !!(condition); \
	92	\
	93	if (unlikely(rtn && __ratelimit(&_rs))) \
	94	WARN(rtn, format, ##__VA_ARGS__); \
	95	\
	96	rtn; \
86e4ca66 DM	97	})
	98
	99	#else
	100
	101	#define WARN_ON_RATELIMIT(condition, state) \
	102	WARN_ON(condition)
	103
2351a6c6	104	#define WARN_RATELIMIT(condition, format, ...) \
86e4ca66	105	({ \
2351a6c6	106	int rtn = WARN(condition, format, ##__VA_ARGS__); \
86e4ca66 DM	107	rtn; \
	108	})
	109
	110	#endif
	111
979f693d	112	#endif /* _LINUX_RATELIMIT_H */