time.h 8.8 KB

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  1. #ifndef _LINUX_TIME_H
  2. #define _LINUX_TIME_H
  3. #include <linux/types.h>
  4. #ifdef __KERNEL__
  5. # include <linux/cache.h>
  6. # include <linux/seqlock.h>
  7. # include <linux/math64.h>
  8. #endif
  9. #ifndef _STRUCT_TIMESPEC
  10. #define _STRUCT_TIMESPEC
  11. struct timespec {
  12. __kernel_time_t tv_sec; /* seconds */
  13. long tv_nsec; /* nanoseconds */
  14. };
  15. #endif
  16. struct timeval {
  17. __kernel_time_t tv_sec; /* seconds */
  18. __kernel_suseconds_t tv_usec; /* microseconds */
  19. };
  20. struct timezone {
  21. int tz_minuteswest; /* minutes west of Greenwich */
  22. int tz_dsttime; /* type of dst correction */
  23. };
  24. #ifdef __KERNEL__
  25. extern struct timezone sys_tz;
  26. /* Parameters used to convert the timespec values: */
  27. #define MSEC_PER_SEC 1000L
  28. #define USEC_PER_MSEC 1000L
  29. #define NSEC_PER_USEC 1000L
  30. #define NSEC_PER_MSEC 1000000L
  31. #define USEC_PER_SEC 1000000L
  32. #define NSEC_PER_SEC 1000000000L
  33. #define FSEC_PER_SEC 1000000000000000L
  34. #define TIME_T_MAX (time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
  35. static inline int timespec_equal(const struct timespec *a,
  36. const struct timespec *b)
  37. {
  38. return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
  39. }
  40. /*
  41. * lhs < rhs: return <0
  42. * lhs == rhs: return 0
  43. * lhs > rhs: return >0
  44. */
  45. static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs)
  46. {
  47. if (lhs->tv_sec < rhs->tv_sec)
  48. return -1;
  49. if (lhs->tv_sec > rhs->tv_sec)
  50. return 1;
  51. return lhs->tv_nsec - rhs->tv_nsec;
  52. }
  53. static inline int timeval_compare(const struct timeval *lhs, const struct timeval *rhs)
  54. {
  55. if (lhs->tv_sec < rhs->tv_sec)
  56. return -1;
  57. if (lhs->tv_sec > rhs->tv_sec)
  58. return 1;
  59. return lhs->tv_usec - rhs->tv_usec;
  60. }
  61. extern unsigned long mktime(const unsigned int year, const unsigned int mon,
  62. const unsigned int day, const unsigned int hour,
  63. const unsigned int min, const unsigned int sec);
  64. extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec);
  65. /*
  66. * timespec_add_safe assumes both values are positive and checks
  67. * for overflow. It will return TIME_T_MAX if the reutrn would be
  68. * smaller then either of the arguments.
  69. */
  70. extern struct timespec timespec_add_safe(const struct timespec lhs,
  71. const struct timespec rhs);
  72. static inline struct timespec timespec_add(struct timespec lhs,
  73. struct timespec rhs)
  74. {
  75. struct timespec ts_delta;
  76. set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec,
  77. lhs.tv_nsec + rhs.tv_nsec);
  78. return ts_delta;
  79. }
  80. /*
  81. * sub = lhs - rhs, in normalized form
  82. */
  83. static inline struct timespec timespec_sub(struct timespec lhs,
  84. struct timespec rhs)
  85. {
  86. struct timespec ts_delta;
  87. set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
  88. lhs.tv_nsec - rhs.tv_nsec);
  89. return ts_delta;
  90. }
  91. /*
  92. * Returns true if the timespec is norm, false if denorm:
  93. */
  94. #define timespec_valid(ts) \
  95. (((ts)->tv_sec >= 0) && (((unsigned long) (ts)->tv_nsec) < NSEC_PER_SEC))
  96. extern struct timespec xtime;
  97. extern struct timespec wall_to_monotonic;
  98. extern seqlock_t xtime_lock;
  99. extern void read_persistent_clock(struct timespec *ts);
  100. extern void read_boot_clock(struct timespec *ts);
  101. extern int update_persistent_clock(struct timespec now);
  102. extern int no_sync_cmos_clock __read_mostly;
  103. void timekeeping_init(void);
  104. extern int timekeeping_suspended;
  105. unsigned long get_seconds(void);
  106. struct timespec current_kernel_time(void);
  107. struct timespec __current_kernel_time(void); /* does not take xtime_lock */
  108. struct timespec __get_wall_to_monotonic(void); /* does not take xtime_lock */
  109. struct timespec get_monotonic_coarse(void);
  110. #define CURRENT_TIME (current_kernel_time())
  111. #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 })
  112. /* Some architectures do not supply their own clocksource.
  113. * This is mainly the case in architectures that get their
  114. * inter-tick times by reading the counter on their interval
  115. * timer. Since these timers wrap every tick, they're not really
  116. * useful as clocksources. Wrapping them to act like one is possible
  117. * but not very efficient. So we provide a callout these arches
  118. * can implement for use with the jiffies clocksource to provide
  119. * finer then tick granular time.
  120. */
  121. #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
  122. extern u32 arch_gettimeoffset(void);
  123. #else
  124. static inline u32 arch_gettimeoffset(void) { return 0; }
  125. #endif
  126. extern void do_gettimeofday(struct timeval *tv);
  127. extern int do_settimeofday(struct timespec *tv);
  128. extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz);
  129. #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
  130. extern long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags);
  131. struct itimerval;
  132. extern int do_setitimer(int which, struct itimerval *value,
  133. struct itimerval *ovalue);
  134. extern unsigned int alarm_setitimer(unsigned int seconds);
  135. extern int do_getitimer(int which, struct itimerval *value);
  136. extern void getnstimeofday(struct timespec *tv);
  137. extern void getrawmonotonic(struct timespec *ts);
  138. extern void getboottime(struct timespec *ts);
  139. extern void monotonic_to_bootbased(struct timespec *ts);
  140. extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
  141. extern int timekeeping_valid_for_hres(void);
  142. extern u64 timekeeping_max_deferment(void);
  143. extern void update_wall_time(void);
  144. extern void timekeeping_leap_insert(int leapsecond);
  145. struct tms;
  146. extern void do_sys_times(struct tms *);
  147. /*
  148. * Similar to the struct tm in userspace <time.h>, but it needs to be here so
  149. * that the kernel source is self contained.
  150. */
  151. struct tm {
  152. /*
  153. * the number of seconds after the minute, normally in the range
  154. * 0 to 59, but can be up to 60 to allow for leap seconds
  155. */
  156. int tm_sec;
  157. /* the number of minutes after the hour, in the range 0 to 59*/
  158. int tm_min;
  159. /* the number of hours past midnight, in the range 0 to 23 */
  160. int tm_hour;
  161. /* the day of the month, in the range 1 to 31 */
  162. int tm_mday;
  163. /* the number of months since January, in the range 0 to 11 */
  164. int tm_mon;
  165. /* the number of years since 1900 */
  166. long tm_year;
  167. /* the number of days since Sunday, in the range 0 to 6 */
  168. int tm_wday;
  169. /* the number of days since January 1, in the range 0 to 365 */
  170. int tm_yday;
  171. };
  172. void time_to_tm(time_t totalsecs, int offset, struct tm *result);
  173. /**
  174. * timespec_to_ns - Convert timespec to nanoseconds
  175. * @ts: pointer to the timespec variable to be converted
  176. *
  177. * Returns the scalar nanosecond representation of the timespec
  178. * parameter.
  179. */
  180. static inline s64 timespec_to_ns(const struct timespec *ts)
  181. {
  182. return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
  183. }
  184. /**
  185. * timeval_to_ns - Convert timeval to nanoseconds
  186. * @ts: pointer to the timeval variable to be converted
  187. *
  188. * Returns the scalar nanosecond representation of the timeval
  189. * parameter.
  190. */
  191. static inline s64 timeval_to_ns(const struct timeval *tv)
  192. {
  193. return ((s64) tv->tv_sec * NSEC_PER_SEC) +
  194. tv->tv_usec * NSEC_PER_USEC;
  195. }
  196. /**
  197. * ns_to_timespec - Convert nanoseconds to timespec
  198. * @nsec: the nanoseconds value to be converted
  199. *
  200. * Returns the timespec representation of the nsec parameter.
  201. */
  202. extern struct timespec ns_to_timespec(const s64 nsec);
  203. /**
  204. * ns_to_timeval - Convert nanoseconds to timeval
  205. * @nsec: the nanoseconds value to be converted
  206. *
  207. * Returns the timeval representation of the nsec parameter.
  208. */
  209. extern struct timeval ns_to_timeval(const s64 nsec);
  210. /**
  211. * timespec_add_ns - Adds nanoseconds to a timespec
  212. * @a: pointer to timespec to be incremented
  213. * @ns: unsigned nanoseconds value to be added
  214. *
  215. * This must always be inlined because its used from the x86-64 vdso,
  216. * which cannot call other kernel functions.
  217. */
  218. static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
  219. {
  220. a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
  221. a->tv_nsec = ns;
  222. }
  223. #endif /* __KERNEL__ */
  224. #define NFDBITS __NFDBITS
  225. #define FD_SETSIZE __FD_SETSIZE
  226. #define FD_SET(fd,fdsetp) __FD_SET(fd,fdsetp)
  227. #define FD_CLR(fd,fdsetp) __FD_CLR(fd,fdsetp)
  228. #define FD_ISSET(fd,fdsetp) __FD_ISSET(fd,fdsetp)
  229. #define FD_ZERO(fdsetp) __FD_ZERO(fdsetp)
  230. /*
  231. * Names of the interval timers, and structure
  232. * defining a timer setting:
  233. */
  234. #define ITIMER_REAL 0
  235. #define ITIMER_VIRTUAL 1
  236. #define ITIMER_PROF 2
  237. struct itimerspec {
  238. struct timespec it_interval; /* timer period */
  239. struct timespec it_value; /* timer expiration */
  240. };
  241. struct itimerval {
  242. struct timeval it_interval; /* timer interval */
  243. struct timeval it_value; /* current value */
  244. };
  245. /*
  246. * The IDs of the various system clocks (for POSIX.1b interval timers):
  247. */
  248. #define CLOCK_REALTIME 0
  249. #define CLOCK_MONOTONIC 1
  250. #define CLOCK_PROCESS_CPUTIME_ID 2
  251. #define CLOCK_THREAD_CPUTIME_ID 3
  252. #define CLOCK_MONOTONIC_RAW 4
  253. #define CLOCK_REALTIME_COARSE 5
  254. #define CLOCK_MONOTONIC_COARSE 6
  255. /*
  256. * The IDs of various hardware clocks:
  257. */
  258. #define CLOCK_SGI_CYCLE 10
  259. #define MAX_CLOCKS 16
  260. #define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC)
  261. #define CLOCKS_MONO CLOCK_MONOTONIC
  262. /*
  263. * The various flags for setting POSIX.1b interval timers:
  264. */
  265. #define TIMER_ABSTIME 0x01
  266. #endif