[linux-block.git] / include / linux / timer.h

#ifndef _LINUX_TIMER_H
#define _LINUX_TIMER_H

#include <linux/list.h>
#include <linux/ktime.h>
#include <linux/stddef.h>
#include <linux/debugobjects.h>
#include <linux/stringify.h>

struct tvec_base;

struct timer_list {
	/*
	 * All fields that change during normal runtime grouped to the
	 * same cacheline
	 */
	struct hlist_node	entry;
	unsigned long		expires;
	void			(*function)(unsigned long);
	unsigned long		data;
	u32			flags;

#ifdef CONFIG_TIMER_STATS
	int			start_pid;
	void			*start_site;
	char			start_comm[16];
#endif
#ifdef CONFIG_LOCKDEP
	struct lockdep_map	lockdep_map;
#endif
};

#ifdef CONFIG_LOCKDEP
/*
 * NB: because we have to copy the lockdep_map, setting the lockdep_map key
 * (second argument) here is required, otherwise it could be initialised to
 * the copy of the lockdep_map later! We use the pointer to and the string
 * "<file>:<line>" as the key resp. the name of the lockdep_map.
 */
#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)				\
	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(_kn, &_kn),
#else
#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
#endif

/*
 * A deferrable timer will work normally when the system is busy, but
 * will not cause a CPU to come out of idle just to service it; instead,
 * the timer will be serviced when the CPU eventually wakes up with a
 * subsequent non-deferrable timer.
 *
 * An irqsafe timer is executed with IRQ disabled and it's safe to wait for
 * the completion of the running instance from IRQ handlers, for example,
 * by calling del_timer_sync().
 *
 * Note: The irq disabled callback execution is a special case for
 * workqueue locking issues. It's not meant for executing random crap
 * with interrupts disabled. Abuse is monitored!
 */
#define TIMER_CPUMASK		0x0003FFFF
#define TIMER_MIGRATING		0x00040000
#define TIMER_BASEMASK		(TIMER_CPUMASK | TIMER_MIGRATING)
#define TIMER_DEFERRABLE	0x00080000
#define TIMER_PINNED		0x00100000
#define TIMER_IRQSAFE		0x00200000
#define TIMER_ARRAYSHIFT	22
#define TIMER_ARRAYMASK		0xFFC00000

#define __TIMER_INITIALIZER(_function, _expires, _data, _flags) { \
		.entry = { .next = TIMER_ENTRY_STATIC },	\
		.function = (_function),			\
		.expires = (_expires),				\
		.data = (_data),				\
		.flags = (_flags),				\
		__TIMER_LOCKDEP_MAP_INITIALIZER(		\
			__FILE__ ":" __stringify(__LINE__))	\
	}

#define TIMER_INITIALIZER(_function, _expires, _data)		\
	__TIMER_INITIALIZER((_function), (_expires), (_data), 0)

#define TIMER_PINNED_INITIALIZER(_function, _expires, _data)	\
	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_PINNED)

#define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data)	\
	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE)

#define TIMER_PINNED_DEFERRED_INITIALIZER(_function, _expires, _data)	\
	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE | TIMER_PINNED)

#define DEFINE_TIMER(_name, _function, _expires, _data)		\
	struct timer_list _name =				\
		TIMER_INITIALIZER(_function, _expires, _data)

void init_timer_key(struct timer_list *timer, unsigned int flags,
		    const char *name, struct lock_class_key *key);

#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
extern void init_timer_on_stack_key(struct timer_list *timer,
				    unsigned int flags, const char *name,
				    struct lock_class_key *key);
extern void destroy_timer_on_stack(struct timer_list *timer);
#else
static inline void destroy_timer_on_stack(struct timer_list *timer) { }
static inline void init_timer_on_stack_key(struct timer_list *timer,
					   unsigned int flags, const char *name,
					   struct lock_class_key *key)
{
	init_timer_key(timer, flags, name, key);
}
#endif

#ifdef CONFIG_LOCKDEP
#define __init_timer(_timer, _flags)					\
	do {								\
		static struct lock_class_key __key;			\
		init_timer_key((_timer), (_flags), #_timer, &__key);	\
	} while (0)

#define __init_timer_on_stack(_timer, _flags)				\
	do {								\
		static struct lock_class_key __key;			\
		init_timer_on_stack_key((_timer), (_flags), #_timer, &__key); \
	} while (0)
#else
#define __init_timer(_timer, _flags)					\
	init_timer_key((_timer), (_flags), NULL, NULL)
#define __init_timer_on_stack(_timer, _flags)				\
	init_timer_on_stack_key((_timer), (_flags), NULL, NULL)
#endif

#define init_timer(timer)						\
	__init_timer((timer), 0)
#define init_timer_pinned(timer)					\
	__init_timer((timer), TIMER_PINNED)
#define init_timer_deferrable(timer)					\
	__init_timer((timer), TIMER_DEFERRABLE)
#define init_timer_pinned_deferrable(timer)				\
	__init_timer((timer), TIMER_DEFERRABLE | TIMER_PINNED)
#define init_timer_on_stack(timer)					\
	__init_timer_on_stack((timer), 0)

#define __setup_timer(_timer, _fn, _data, _flags)			\
	do {								\
		__init_timer((_timer), (_flags));			\
		(_timer)->function = (_fn);				\
		(_timer)->data = (_data);				\
	} while (0)

#define __setup_timer_on_stack(_timer, _fn, _data, _flags)		\
	do {								\
		__init_timer_on_stack((_timer), (_flags));		\
		(_timer)->function = (_fn);				\
		(_timer)->data = (_data);				\
	} while (0)

#define setup_timer(timer, fn, data)					\
	__setup_timer((timer), (fn), (data), 0)
#define setup_pinned_timer(timer, fn, data)				\
	__setup_timer((timer), (fn), (data), TIMER_PINNED)
#define setup_deferrable_timer(timer, fn, data)				\
	__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE)
#define setup_pinned_deferrable_timer(timer, fn, data)			\
	__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)
#define setup_timer_on_stack(timer, fn, data)				\
	__setup_timer_on_stack((timer), (fn), (data), 0)
#define setup_pinned_timer_on_stack(timer, fn, data)			\
	__setup_timer_on_stack((timer), (fn), (data), TIMER_PINNED)
#define setup_deferrable_timer_on_stack(timer, fn, data)		\
	__setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE)
#define setup_pinned_deferrable_timer_on_stack(timer, fn, data)		\
	__setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)

/**
 * timer_pending - is a timer pending?
 * @timer: the timer in question
 *
 * timer_pending will tell whether a given timer is currently pending,
 * or not. Callers must ensure serialization wrt. other operations done
 * to this timer, eg. interrupt contexts, or other CPUs on SMP.
 *
 * return value: 1 if the timer is pending, 0 if not.
 */
static inline int timer_pending(const struct timer_list * timer)
{
	return timer->entry.pprev != NULL;
}

extern void add_timer_on(struct timer_list *timer, int cpu);
extern int del_timer(struct timer_list * timer);
extern int mod_timer(struct timer_list *timer, unsigned long expires);
extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);

/*
 * The jiffies value which is added to now, when there is no timer
 * in the timer wheel:
 */
#define NEXT_TIMER_MAX_DELTA	((1UL << 30) - 1)

/*
 * Timer-statistics info:
 */
#ifdef CONFIG_TIMER_STATS

extern int timer_stats_active;

extern void init_timer_stats(void);

extern void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
				     void *timerf, char *comm, u32 flags);

extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
					       void *addr);

static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
{
	if (likely(!timer_stats_active))
		return;
	__timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
}

static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
{
	timer->start_site = NULL;
}
#else
static inline void init_timer_stats(void)
{
}

static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
{
}

static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
{
}
#endif

extern void add_timer(struct timer_list *timer);

extern int try_to_del_timer_sync(struct timer_list *timer);

#ifdef CONFIG_SMP
  extern int del_timer_sync(struct timer_list *timer);
#else
# define del_timer_sync(t)		del_timer(t)
#endif

#define del_singleshot_timer_sync(t) del_timer_sync(t)

extern void init_timers(void);
extern void run_local_timers(void);
struct hrtimer;
extern enum hrtimer_restart it_real_fn(struct hrtimer *);

#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
#include <linux/sysctl.h>

extern unsigned int sysctl_timer_migration;
int timer_migration_handler(struct ctl_table *table, int write,
			    void __user *buffer, size_t *lenp,
			    loff_t *ppos);
#endif

unsigned long __round_jiffies(unsigned long j, int cpu);
unsigned long __round_jiffies_relative(unsigned long j, int cpu);
unsigned long round_jiffies(unsigned long j);
unsigned long round_jiffies_relative(unsigned long j);

unsigned long __round_jiffies_up(unsigned long j, int cpu);
unsigned long __round_jiffies_up_relative(unsigned long j, int cpu);
unsigned long round_jiffies_up(unsigned long j);
unsigned long round_jiffies_up_relative(unsigned long j);

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_TIMER_H
	2	#define _LINUX_TIMER_H
	3
1da177e4	4	#include <linux/list.h>
82f67cd9	5	#include <linux/ktime.h>
1da177e4	6	#include <linux/stddef.h>
c6f3a97f	7	#include <linux/debugobjects.h>
6f2b9b9a	8	#include <linux/stringify.h>
1da177e4	9
a6fa8e5a	10	struct tvec_base;
1da177e4 LT	11
1da177e4 LT	12	struct timer_list {
3bbb9ec9 AV	13	/*
	14	* All fields that change during normal runtime grouped to the
	15	* same cacheline
	16	*/
0eeda71b TG	17	struct hlist_node entry;
	18	unsigned long expires;
	19	void (*function)(unsigned long);
	20	unsigned long data;
	21	u32 flags;
3bbb9ec9	22
82f67cd9	23	#ifdef CONFIG_TIMER_STATS
0eeda71b TG	24	int start_pid;
	25	void *start_site;
	26	char start_comm[16];
82f67cd9	27	#endif
6f2b9b9a	28	#ifdef CONFIG_LOCKDEP
0eeda71b	29	struct lockdep_map lockdep_map;
6f2b9b9a	30	#endif
1da177e4 LT	31	};
1da177e4 LT	32
6f2b9b9a JB	33	#ifdef CONFIG_LOCKDEP
	34	/*
	35	* NB: because we have to copy the lockdep_map, setting the lockdep_map key
	36	* (second argument) here is required, otherwise it could be initialised to
	37	* the copy of the lockdep_map later! We use the pointer to and the string
	38	* "<file>:<line>" as the key resp. the name of the lockdep_map.
	39	*/
	40	#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn) \
	41	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(_kn, &_kn),
	42	#else
	43	#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
	44	#endif
	45
dd6414b5	46	/*
dd6414b5 PC	47	* A deferrable timer will work normally when the system is busy, but
	48	* will not cause a CPU to come out of idle just to service it; instead,
	49	* the timer will be serviced when the CPU eventually wakes up with a
	50	* subsequent non-deferrable timer.
c5f66e99 TH	51	*
	52	* An irqsafe timer is executed with IRQ disabled and it's safe to wait for
	53	* the completion of the running instance from IRQ handlers, for example,
	54	* by calling del_timer_sync().
	55	*
	56	* Note: The irq disabled callback execution is a special case for
	57	* workqueue locking issues. It's not meant for executing random crap
	58	* with interrupts disabled. Abuse is monitored!
dd6414b5	59	*/
b0d6e2dc TG	60	#define TIMER_CPUMASK 0x0003FFFF
b0d6e2dc TG	61	#define TIMER_MIGRATING 0x00040000
0eeda71b	62	#define TIMER_BASEMASK (TIMER_CPUMASK \| TIMER_MIGRATING)
b0d6e2dc TG	63	#define TIMER_DEFERRABLE 0x00080000
	64	#define TIMER_PINNED 0x00100000
	65	#define TIMER_IRQSAFE 0x00200000
500462a9 TG	66	#define TIMER_ARRAYSHIFT 22
500462a9 TG	67	#define TIMER_ARRAYMASK 0xFFC00000
dd6414b5	68
fc683995	69	#define __TIMER_INITIALIZER(_function, _expires, _data, _flags) { \
1dabbcec	70	.entry = { .next = TIMER_ENTRY_STATIC }, \
1da177e4 LT	71	.function = (_function), \
	72	.expires = (_expires), \
	73	.data = (_data), \
0eeda71b	74	.flags = (_flags), \
6f2b9b9a JB	75	__TIMER_LOCKDEP_MAP_INITIALIZER( \
6f2b9b9a JB	76	__FILE__ ":" __stringify(__LINE__)) \
1da177e4 LT	77	}
1da177e4 LT	78
fc683995 TH	79	#define TIMER_INITIALIZER(_function, _expires, _data) \
fc683995 TH	80	__TIMER_INITIALIZER((_function), (_expires), (_data), 0)
dd6414b5	81
e675447b TG	82	#define TIMER_PINNED_INITIALIZER(_function, _expires, _data) \
	83	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_PINNED)
	84
fc683995 TH	85	#define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data) \
fc683995 TH	86	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE)
dd6414b5	87
e675447b TG	88	#define TIMER_PINNED_DEFERRED_INITIALIZER(_function, _expires, _data) \
	89	__TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE \| TIMER_PINNED)
	90
8d06afab IM	91	#define DEFINE_TIMER(_name, _function, _expires, _data) \
	92	struct timer_list _name = \
	93	TIMER_INITIALIZER(_function, _expires, _data)
	94
fc683995 TH	95	void init_timer_key(struct timer_list *timer, unsigned int flags,
fc683995 TH	96	const char name, struct lock_class_key key);
6f2b9b9a	97
5a9af38d TH	98	#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
5a9af38d TH	99	extern void init_timer_on_stack_key(struct timer_list *timer,
fc683995	100	unsigned int flags, const char *name,
5a9af38d TH	101	struct lock_class_key *key);
	102	extern void destroy_timer_on_stack(struct timer_list *timer);
	103	#else
	104	static inline void destroy_timer_on_stack(struct timer_list *timer) { }
	105	static inline void init_timer_on_stack_key(struct timer_list *timer,
fc683995	106	unsigned int flags, const char *name,
5a9af38d TH	107	struct lock_class_key *key)
5a9af38d TH	108	{
fc683995	109	init_timer_key(timer, flags, name, key);
5a9af38d TH	110	}
	111	#endif
	112
6f2b9b9a	113	#ifdef CONFIG_LOCKDEP
fc683995	114	#define __init_timer(_timer, _flags) \
6f2b9b9a JB	115	do { \
6f2b9b9a JB	116	static struct lock_class_key __key; \
fc683995	117	init_timer_key((_timer), (_flags), #_timer, &__key); \
6f2b9b9a JB	118	} while (0)
6f2b9b9a JB	119
fc683995	120	#define __init_timer_on_stack(_timer, _flags) \
6f2b9b9a JB	121	do { \
6f2b9b9a JB	122	static struct lock_class_key __key; \
fc683995	123	init_timer_on_stack_key((_timer), (_flags), #_timer, &__key); \
6f2b9b9a	124	} while (0)
fc683995 TH	125	#else
	126	#define __init_timer(_timer, _flags) \
	127	init_timer_key((_timer), (_flags), NULL, NULL)
	128	#define __init_timer_on_stack(_timer, _flags) \
	129	init_timer_on_stack_key((_timer), (_flags), NULL, NULL)
	130	#endif
6f2b9b9a	131
fc683995 TH	132	#define init_timer(timer) \
fc683995 TH	133	__init_timer((timer), 0)
e675447b TG	134	#define init_timer_pinned(timer) \
e675447b TG	135	__init_timer((timer), TIMER_PINNED)
fc683995 TH	136	#define init_timer_deferrable(timer) \
fc683995 TH	137	__init_timer((timer), TIMER_DEFERRABLE)
e675447b TG	138	#define init_timer_pinned_deferrable(timer) \
e675447b TG	139	__init_timer((timer), TIMER_DEFERRABLE \| TIMER_PINNED)
6f2b9b9a	140	#define init_timer_on_stack(timer) \
fc683995 TH	141	__init_timer_on_stack((timer), 0)
	142
	143	#define __setup_timer(_timer, _fn, _data, _flags) \
6f2b9b9a	144	do { \
fc683995 TH	145	__init_timer((_timer), (_flags)); \
	146	(_timer)->function = (_fn); \
	147	(_timer)->data = (_data); \
6f2b9b9a JB	148	} while (0)
6f2b9b9a JB	149
fc683995	150	#define __setup_timer_on_stack(_timer, _fn, _data, _flags) \
6f2b9b9a	151	do { \
fc683995 TH	152	__init_timer_on_stack((_timer), (_flags)); \
	153	(_timer)->function = (_fn); \
	154	(_timer)->data = (_data); \
6f2b9b9a JB	155	} while (0)
6f2b9b9a JB	156
fc683995 TH	157	#define setup_timer(timer, fn, data) \
fc683995 TH	158	__setup_timer((timer), (fn), (data), 0)
e675447b TG	159	#define setup_pinned_timer(timer, fn, data) \
e675447b TG	160	__setup_timer((timer), (fn), (data), TIMER_PINNED)
6f3ffc19 LS	161	#define setup_deferrable_timer(timer, fn, data) \
6f3ffc19 LS	162	__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE)
e675447b TG	163	#define setup_pinned_deferrable_timer(timer, fn, data) \
e675447b TG	164	__setup_timer((timer), (fn), (data), TIMER_DEFERRABLE \| TIMER_PINNED)
6f2b9b9a	165	#define setup_timer_on_stack(timer, fn, data) \
fc683995	166	__setup_timer_on_stack((timer), (fn), (data), 0)
e675447b TG	167	#define setup_pinned_timer_on_stack(timer, fn, data) \
e675447b TG	168	__setup_timer_on_stack((timer), (fn), (data), TIMER_PINNED)
8cadd283	169	#define setup_deferrable_timer_on_stack(timer, fn, data) \
fc683995	170	__setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE)
e675447b TG	171	#define setup_pinned_deferrable_timer_on_stack(timer, fn, data) \
e675447b TG	172	__setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE \| TIMER_PINNED)
8cadd283	173
45f8bde0	174	/**
1da177e4 LT	175	* timer_pending - is a timer pending?
	176	* @timer: the timer in question
	177	*
	178	* timer_pending will tell whether a given timer is currently pending,
	179	* or not. Callers must ensure serialization wrt. other operations done
	180	* to this timer, eg. interrupt contexts, or other CPUs on SMP.
	181	*
	182	* return value: 1 if the timer is pending, 0 if not.
	183	*/
	184	static inline int timer_pending(const struct timer_list * timer)
	185	{
1dabbcec	186	return timer->entry.pprev != NULL;
1da177e4 LT	187	}
	188
	189	extern void add_timer_on(struct timer_list *timer, int cpu);
	190	extern int del_timer(struct timer_list * timer);
1da177e4	191	extern int mod_timer(struct timer_list *timer, unsigned long expires);
74019224	192	extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
1da177e4	193
eaad084b TG	194	/*
	195	* The jiffies value which is added to now, when there is no timer
	196	* in the timer wheel:
	197	*/
	198	#define NEXT_TIMER_MAX_DELTA ((1UL << 30) - 1)
	199
82f67cd9 IM	200	/*
	201	* Timer-statistics info:
	202	*/
	203	#ifdef CONFIG_TIMER_STATS
	204
507e1231 HC	205	extern int timer_stats_active;
507e1231 HC	206
82f67cd9 IM	207	extern void init_timer_stats(void);
	208
	209	extern void timer_stats_update_stats(void timer, pid_t pid, void startf,
c74441a1	210	void timerf, char comm, u32 flags);
82f67cd9 IM	211
	212	extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
	213	void *addr);
	214
	215	static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
	216	{
507e1231 HC	217	if (likely(!timer_stats_active))
507e1231 HC	218	return;
82f67cd9 IM	219	__timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
	220	}
	221
	222	static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
	223	{
	224	timer->start_site = NULL;
	225	}
	226	#else
	227	static inline void init_timer_stats(void)
	228	{
	229	}
	230
82f67cd9 IM	231	static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
	232	{
	233	}
	234
	235	static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
	236	{
	237	}
	238	#endif
	239
74019224	240	extern void add_timer(struct timer_list *timer);
1da177e4	241
6f1bc451 YZ	242	extern int try_to_del_timer_sync(struct timer_list *timer);
6f1bc451 YZ	243
1da177e4 LT	244	#ifdef CONFIG_SMP
1da177e4 LT	245	extern int del_timer_sync(struct timer_list *timer);
1da177e4	246	#else
fd450b73	247	# define del_timer_sync(t) del_timer(t)
1da177e4 LT	248	#endif
1da177e4 LT	249
55c888d6 ON	250	#define del_singleshot_timer_sync(t) del_timer_sync(t)
55c888d6 ON	251
1da177e4 LT	252	extern void init_timers(void);
1da177e4 LT	253	extern void run_local_timers(void);
05cfb614	254	struct hrtimer;
c9cb2e3d	255	extern enum hrtimer_restart it_real_fn(struct hrtimer *);
1da177e4	256
bc7a34b8 TG	257	#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
	258	#include <linux/sysctl.h>
	259
	260	extern unsigned int sysctl_timer_migration;
	261	int timer_migration_handler(struct ctl_table *table, int write,
	262	void __user buffer, size_t lenp,
	263	loff_t *ppos);
	264	#endif
	265
4c36a5de AV	266	unsigned long __round_jiffies(unsigned long j, int cpu);
	267	unsigned long __round_jiffies_relative(unsigned long j, int cpu);
	268	unsigned long round_jiffies(unsigned long j);
	269	unsigned long round_jiffies_relative(unsigned long j);
	270
9c133c46 AS	271	unsigned long __round_jiffies_up(unsigned long j, int cpu);
	272	unsigned long __round_jiffies_up_relative(unsigned long j, int cpu);
	273	unsigned long round_jiffies_up(unsigned long j);
	274	unsigned long round_jiffies_up_relative(unsigned long j);
	275
1da177e4	276	#endif