Blame view
include/linux/hrtimer.h
12.8 KB
c0a313296
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 |
/* * include/linux/hrtimer.h * * hrtimers - High-resolution kernel timers * * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de> * Copyright(C) 2005, Red Hat, Inc., Ingo Molnar * * data type definitions, declarations, prototypes * * Started by: Thomas Gleixner and Ingo Molnar * * For licencing details see kernel-base/COPYING */ #ifndef _LINUX_HRTIMER_H #define _LINUX_HRTIMER_H #include <linux/rbtree.h> #include <linux/ktime.h> #include <linux/init.h> #include <linux/list.h> #include <linux/wait.h> |
40b860625
|
23 |
#include <linux/percpu.h> |
507e12315
|
24 |
#include <linux/timer.h> |
998adc3dd
|
25 |
#include <linux/timerqueue.h> |
c0a313296
|
26 |
|
3c8aa39d7
|
27 28 |
struct hrtimer_clock_base; struct hrtimer_cpu_base; |
c0a313296
|
29 30 31 32 |
/* * Mode arguments of xxx_hrtimer functions: */ enum hrtimer_mode { |
597d02757
|
33 34 35 36 37 |
HRTIMER_MODE_ABS = 0x0, /* Time value is absolute */ HRTIMER_MODE_REL = 0x1, /* Time value is relative to now */ HRTIMER_MODE_PINNED = 0x02, /* Timer is bound to CPU */ HRTIMER_MODE_ABS_PINNED = 0x02, HRTIMER_MODE_REL_PINNED = 0x03, |
c0a313296
|
38 |
}; |
c9cb2e3d7
|
39 40 41 |
/* * Return values for the callback function */ |
c0a313296
|
42 |
enum hrtimer_restart { |
c9cb2e3d7
|
43 44 |
HRTIMER_NORESTART, /* Timer is not restarted */ HRTIMER_RESTART, /* Timer must be restarted */ |
c0a313296
|
45 |
}; |
303e967ff
|
46 |
/* |
54cdfdb47
|
47 |
* Values to track state of the timer |
303e967ff
|
48 49 50 51 52 53 |
* * Possible states: * * 0x00 inactive * 0x01 enqueued into rbtree * 0x02 callback function running |
54cdfdb47
|
54 |
* |
b00c1a99e
|
55 |
* Special cases: |
303e967ff
|
56 57 |
* 0x03 callback function running and enqueued * (was requeued on another CPU) |
b00c1a99e
|
58 |
* 0x09 timer was migrated on CPU hotunplug |
303e967ff
|
59 60 61 62 63 64 65 66 |
* The "callback function running and enqueued" status is only possible on * SMP. It happens for example when a posix timer expired and the callback * queued a signal. Between dropping the lock which protects the posix timer * and reacquiring the base lock of the hrtimer, another CPU can deliver the * signal and rearm the timer. We have to preserve the callback running state, * as otherwise the timer could be removed before the softirq code finishes the * the handling of the timer. * |
3eb056764
|
67 |
* The HRTIMER_STATE_ENQUEUED bit is always or'ed to the current state to |
303e967ff
|
68 69 70 71 72 73 74 |
* preserve the HRTIMER_STATE_CALLBACK bit in the above scenario. * * All state transitions are protected by cpu_base->lock. */ #define HRTIMER_STATE_INACTIVE 0x00 #define HRTIMER_STATE_ENQUEUED 0x01 #define HRTIMER_STATE_CALLBACK 0x02 |
ca109491f
|
75 |
#define HRTIMER_STATE_MIGRATE 0x04 |
303e967ff
|
76 |
|
c0a313296
|
77 78 |
/** * struct hrtimer - the basic hrtimer structure |
998adc3dd
|
79 80 |
* @node: timerqueue node, which also manages node.expires, * the absolute expiry time in the hrtimers internal |
c0a313296
|
81 |
* representation. The time is related to the clock on |
592aa999d
|
82 83 84 85 86 87 |
* which the timer is based. Is setup by adding * slack to the _softexpires value. For non range timers * identical to _softexpires. * @_softexpires: the absolute earliest expiry time of the hrtimer. * The time which was given as expiry time when the timer * was armed. |
c0a313296
|
88 |
* @function: timer expiry callback function |
c0a313296
|
89 |
* @base: pointer to the timer base (per cpu and per clock) |
303e967ff
|
90 |
* @state: state information (See bit values above) |
54cdfdb47
|
91 92 93 94 95 96 |
* @start_site: timer statistics field to store the site where the timer * was started * @start_comm: timer statistics field to store the name of the process which * started the timer * @start_pid: timer statistics field to store the pid of the task which * started the timer |
c0a313296
|
97 |
* |
54cdfdb47
|
98 |
* The hrtimer structure must be initialized by hrtimer_init() |
c0a313296
|
99 100 |
*/ struct hrtimer { |
998adc3dd
|
101 |
struct timerqueue_node node; |
654c8e0b1
|
102 |
ktime_t _softexpires; |
3c8aa39d7
|
103 104 |
enum hrtimer_restart (*function)(struct hrtimer *); struct hrtimer_clock_base *base; |
303e967ff
|
105 |
unsigned long state; |
82f67cd9f
|
106 |
#ifdef CONFIG_TIMER_STATS |
1b0246908
|
107 |
int start_pid; |
82f67cd9f
|
108 109 |
void *start_site; char start_comm[16]; |
82f67cd9f
|
110 |
#endif |
c0a313296
|
111 112 113 |
}; /** |
00362e33f
|
114 |
* struct hrtimer_sleeper - simple sleeper structure |
00362e33f
|
115 116 117 118 119 120 121 122 123 124 125 |
* @timer: embedded timer structure * @task: task to wake up * * task is set to NULL, when the timer expires. */ struct hrtimer_sleeper { struct hrtimer timer; struct task_struct *task; }; /** |
d1d67174b
|
126 |
* struct hrtimer_clock_base - the timer base for a specific clock |
05fb6bf0b
|
127 |
* @cpu_base: per cpu clock base |
3c8aa39d7
|
128 129 |
* @index: clock type index for per_cpu support when moving a * timer to a base on another cpu. |
92127c7a4
|
130 |
* @active: red black tree root node for the active timers |
92127c7a4
|
131 132 |
* @resolution: the resolution of the clock, in nanoseconds * @get_time: function to retrieve the current time of the clock |
92127c7a4
|
133 |
* @softirq_time: the time when running the hrtimer queue in the softirq |
54cdfdb47
|
134 |
* @offset: offset of this clock to the monotonic base |
c0a313296
|
135 |
*/ |
3c8aa39d7
|
136 137 |
struct hrtimer_clock_base { struct hrtimer_cpu_base *cpu_base; |
c0a313296
|
138 |
clockid_t index; |
998adc3dd
|
139 |
struct timerqueue_head active; |
e2787630c
|
140 |
ktime_t resolution; |
c0a313296
|
141 |
ktime_t (*get_time)(void); |
92127c7a4
|
142 |
ktime_t softirq_time; |
54cdfdb47
|
143 144 |
#ifdef CONFIG_HIGH_RES_TIMERS ktime_t offset; |
54cdfdb47
|
145 |
#endif |
3c8aa39d7
|
146 147 148 149 150 151 152 153 |
}; #define HRTIMER_MAX_CLOCK_BASES 2 /* * struct hrtimer_cpu_base - the per cpu clock bases * @lock: lock protecting the base and associated clock bases * and timers |
3c8aa39d7
|
154 |
* @clock_base: array of clock bases for this cpu |
54cdfdb47
|
155 156 157 |
* @expires_next: absolute time of the next event which was scheduled * via clock_set_next_event() * @hres_active: State of high resolution mode |
41d2e4949
|
158 159 160 161 162 |
* @hang_detected: The last hrtimer interrupt detected a hang * @nr_events: Total number of hrtimer interrupt events * @nr_retries: Total number of hrtimer interrupt retries * @nr_hangs: Total number of hrtimer interrupt hangs * @max_hang_time: Maximum time spent in hrtimer_interrupt |
3c8aa39d7
|
163 164 |
*/ struct hrtimer_cpu_base { |
ecb49d1a6
|
165 |
raw_spinlock_t lock; |
3c8aa39d7
|
166 |
struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES]; |
54cdfdb47
|
167 168 169 |
#ifdef CONFIG_HIGH_RES_TIMERS ktime_t expires_next; int hres_active; |
41d2e4949
|
170 |
int hang_detected; |
54cdfdb47
|
171 |
unsigned long nr_events; |
41d2e4949
|
172 173 174 |
unsigned long nr_retries; unsigned long nr_hangs; ktime_t max_hang_time; |
54cdfdb47
|
175 |
#endif |
c0a313296
|
176 |
}; |
63ca243b2
|
177 178 |
static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time) { |
998adc3dd
|
179 |
timer->node.expires = time; |
654c8e0b1
|
180 |
timer->_softexpires = time; |
63ca243b2
|
181 |
} |
654c8e0b1
|
182 183 184 185 |
static inline void hrtimer_set_expires_range(struct hrtimer *timer, ktime_t time, ktime_t delta) { timer->_softexpires = time; |
998adc3dd
|
186 |
timer->node.expires = ktime_add_safe(time, delta); |
654c8e0b1
|
187 188 189 190 191 |
} static inline void hrtimer_set_expires_range_ns(struct hrtimer *timer, ktime_t time, unsigned long delta) { timer->_softexpires = time; |
998adc3dd
|
192 |
timer->node.expires = ktime_add_safe(time, ns_to_ktime(delta)); |
654c8e0b1
|
193 |
} |
63ca243b2
|
194 195 |
static inline void hrtimer_set_expires_tv64(struct hrtimer *timer, s64 tv64) { |
998adc3dd
|
196 |
timer->node.expires.tv64 = tv64; |
654c8e0b1
|
197 |
timer->_softexpires.tv64 = tv64; |
63ca243b2
|
198 199 200 201 |
} static inline void hrtimer_add_expires(struct hrtimer *timer, ktime_t time) { |
998adc3dd
|
202 |
timer->node.expires = ktime_add_safe(timer->node.expires, time); |
654c8e0b1
|
203 |
timer->_softexpires = ktime_add_safe(timer->_softexpires, time); |
63ca243b2
|
204 |
} |
7597bc94d
|
205 |
static inline void hrtimer_add_expires_ns(struct hrtimer *timer, u64 ns) |
63ca243b2
|
206 |
{ |
998adc3dd
|
207 |
timer->node.expires = ktime_add_ns(timer->node.expires, ns); |
654c8e0b1
|
208 |
timer->_softexpires = ktime_add_ns(timer->_softexpires, ns); |
63ca243b2
|
209 210 211 212 |
} static inline ktime_t hrtimer_get_expires(const struct hrtimer *timer) { |
998adc3dd
|
213 |
return timer->node.expires; |
63ca243b2
|
214 |
} |
654c8e0b1
|
215 216 217 218 |
static inline ktime_t hrtimer_get_softexpires(const struct hrtimer *timer) { return timer->_softexpires; } |
63ca243b2
|
219 220 |
static inline s64 hrtimer_get_expires_tv64(const struct hrtimer *timer) { |
998adc3dd
|
221 |
return timer->node.expires.tv64; |
63ca243b2
|
222 |
} |
654c8e0b1
|
223 224 225 226 |
static inline s64 hrtimer_get_softexpires_tv64(const struct hrtimer *timer) { return timer->_softexpires.tv64; } |
63ca243b2
|
227 228 229 |
static inline s64 hrtimer_get_expires_ns(const struct hrtimer *timer) { |
998adc3dd
|
230 |
return ktime_to_ns(timer->node.expires); |
63ca243b2
|
231 232 233 234 |
} static inline ktime_t hrtimer_expires_remaining(const struct hrtimer *timer) { |
998adc3dd
|
235 |
return ktime_sub(timer->node.expires, timer->base->get_time()); |
63ca243b2
|
236 |
} |
54cdfdb47
|
237 238 239 240 |
#ifdef CONFIG_HIGH_RES_TIMERS struct clock_event_device; extern void clock_was_set(void); |
995f054f2
|
241 |
extern void hres_timers_resume(void); |
54cdfdb47
|
242 243 244 245 246 247 248 249 250 |
extern void hrtimer_interrupt(struct clock_event_device *dev); /* * In high resolution mode the time reference must be read accurate */ static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer) { return timer->base->get_time(); } |
8f4d37ec0
|
251 252 253 254 |
static inline int hrtimer_is_hres_active(struct hrtimer *timer) { return timer->base->cpu_base->hres_active; } |
2075eb8d9
|
255 |
extern void hrtimer_peek_ahead_timers(void); |
54cdfdb47
|
256 257 258 259 260 261 |
/* * The resolution of the clocks. The resolution value is returned in * the clock_getres() system call to give application programmers an * idea of the (in)accuracy of timers. Timer values are rounded up to * this resolution values. */ |
151db1fc2
|
262 263 264 |
# define HIGH_RES_NSEC 1 # define KTIME_HIGH_RES (ktime_t) { .tv64 = HIGH_RES_NSEC } # define MONOTONIC_RES_NSEC HIGH_RES_NSEC |
54cdfdb47
|
265 266 267 |
# define KTIME_MONOTONIC_RES KTIME_HIGH_RES #else |
151db1fc2
|
268 |
# define MONOTONIC_RES_NSEC LOW_RES_NSEC |
54cdfdb47
|
269 |
# define KTIME_MONOTONIC_RES KTIME_LOW_RES |
becf8b5d0
|
270 271 272 273 274 |
/* * clock_was_set() is a NOP for non- high-resolution systems. The * time-sorted order guarantees that a timer does not expire early and * is expired in the next softirq when the clock was advanced. */ |
54cdfdb47
|
275 |
static inline void clock_was_set(void) { } |
2075eb8d9
|
276 |
static inline void hrtimer_peek_ahead_timers(void) { } |
54cdfdb47
|
277 |
|
995f054f2
|
278 |
static inline void hres_timers_resume(void) { } |
54cdfdb47
|
279 280 281 282 283 284 285 286 |
/* * In non high resolution mode the time reference is taken from * the base softirq time variable. */ static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer) { return timer->base->softirq_time; } |
8f4d37ec0
|
287 288 289 290 |
static inline int hrtimer_is_hres_active(struct hrtimer *timer) { return 0; } |
54cdfdb47
|
291 |
#endif |
d316c57ff
|
292 293 |
extern ktime_t ktime_get(void); extern ktime_t ktime_get_real(void); |
becf8b5d0
|
294 |
|
2e94d1f71
|
295 296 |
DECLARE_PER_CPU(struct tick_device, tick_cpu_device); |
2e94d1f71
|
297 |
|
c0a313296
|
298 299 300 |
/* Exported timer functions: */ /* Initialize timers: */ |
7978672c4
|
301 302 |
extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock, enum hrtimer_mode mode); |
c0a313296
|
303 |
|
237fc6e7a
|
304 305 306 307 308 309 310 311 312 313 314 315 316 317 |
#ifdef CONFIG_DEBUG_OBJECTS_TIMERS extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock, enum hrtimer_mode mode); extern void destroy_hrtimer_on_stack(struct hrtimer *timer); #else static inline void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock, enum hrtimer_mode mode) { hrtimer_init(timer, which_clock, mode); } static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { } #endif |
c0a313296
|
318 319 320 |
/* Basic timer operations: */ extern int hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode); |
da8f2e170
|
321 322 |
extern int hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, unsigned long range_ns, const enum hrtimer_mode mode); |
7f1e2ca9f
|
323 324 325 326 |
extern int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, unsigned long delta_ns, const enum hrtimer_mode mode, int wakeup); |
c0a313296
|
327 328 |
extern int hrtimer_cancel(struct hrtimer *timer); extern int hrtimer_try_to_cancel(struct hrtimer *timer); |
63ca243b2
|
329 330 331 |
static inline int hrtimer_start_expires(struct hrtimer *timer, enum hrtimer_mode mode) { |
da8f2e170
|
332 333 334 335 336 |
unsigned long delta; ktime_t soft, hard; soft = hrtimer_get_softexpires(timer); hard = hrtimer_get_expires(timer); delta = ktime_to_ns(ktime_sub(hard, soft)); |
4ce105d30
|
337 |
return hrtimer_start_range_ns(timer, soft, delta, mode); |
63ca243b2
|
338 |
} |
c9cb2e3d7
|
339 340 |
static inline int hrtimer_restart(struct hrtimer *timer) { |
654c8e0b1
|
341 |
return hrtimer_start_expires(timer, HRTIMER_MODE_ABS); |
c9cb2e3d7
|
342 |
} |
c0a313296
|
343 344 345 346 |
/* Query timers: */ extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer); extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp); |
69239749e
|
347 |
extern ktime_t hrtimer_get_next_event(void); |
69239749e
|
348 |
|
303e967ff
|
349 350 351 352 |
/* * A timer is active, when it is enqueued into the rbtree or the callback * function is running. */ |
c0a313296
|
353 354 |
static inline int hrtimer_active(const struct hrtimer *timer) { |
303e967ff
|
355 |
return timer->state != HRTIMER_STATE_INACTIVE; |
c0a313296
|
356 |
} |
54cdfdb47
|
357 358 359 360 361 |
/* * Helper function to check, whether the timer is on one of the queues */ static inline int hrtimer_is_queued(struct hrtimer *timer) { |
ca109491f
|
362 |
return timer->state & HRTIMER_STATE_ENQUEUED; |
54cdfdb47
|
363 |
} |
4346f6542
|
364 365 366 367 368 369 370 371 |
/* * Helper function to check, whether the timer is running the callback * function */ static inline int hrtimer_callback_running(struct hrtimer *timer) { return timer->state & HRTIMER_STATE_CALLBACK; } |
c0a313296
|
372 |
/* Forward a hrtimer so it expires after now: */ |
4d672e7ac
|
373 |
extern u64 |
44f214755
|
374 |
hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval); |
c0a313296
|
375 |
|
5e05ad7d4
|
376 |
/* Forward a hrtimer so it expires after the hrtimer's current now */ |
4d672e7ac
|
377 378 |
static inline u64 hrtimer_forward_now(struct hrtimer *timer, ktime_t interval) |
5e05ad7d4
|
379 380 381 |
{ return hrtimer_forward(timer, timer->base->get_time(), interval); } |
10c94ec16
|
382 383 |
/* Precise sleep: */ extern long hrtimer_nanosleep(struct timespec *rqtp, |
080344b98
|
384 |
struct timespec __user *rmtp, |
10c94ec16
|
385 386 |
const enum hrtimer_mode mode, const clockid_t clockid); |
1711ef386
|
387 |
extern long hrtimer_nanosleep_restart(struct restart_block *restart_block); |
10c94ec16
|
388 |
|
00362e33f
|
389 390 |
extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *tsk); |
654c8e0b1
|
391 392 |
extern int schedule_hrtimeout_range(ktime_t *expires, unsigned long delta, const enum hrtimer_mode mode); |
351b3f7a2
|
393 394 |
extern int schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta, const enum hrtimer_mode mode, int clock); |
7bb67439b
|
395 |
extern int schedule_hrtimeout(ktime_t *expires, const enum hrtimer_mode mode); |
c0a313296
|
396 397 |
/* Soft interrupt function to run the hrtimer queues: */ extern void hrtimer_run_queues(void); |
d3d74453c
|
398 |
extern void hrtimer_run_pending(void); |
c0a313296
|
399 400 401 |
/* Bootup initialization: */ extern void __init hrtimers_init(void); |
79bf2bb33
|
402 |
#if BITS_PER_LONG < 64 |
4d672e7ac
|
403 |
extern u64 ktime_divns(const ktime_t kt, s64 div); |
79bf2bb33
|
404 |
#else /* BITS_PER_LONG < 64 */ |
4d672e7ac
|
405 |
# define ktime_divns(kt, div) (u64)((kt).tv64 / (div)) |
79bf2bb33
|
406 |
#endif |
88ad0bf68
|
407 408 |
/* Show pending timers: */ extern void sysrq_timer_list_show(void); |
c0a313296
|
409 |
#endif |