time.h 8.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292
  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. extern struct timespec timespec_add_safe(const struct timespec lhs,
  66. const struct timespec rhs);
  67. /*
  68. * sub = lhs - rhs, in normalized form
  69. */
  70. static inline struct timespec timespec_sub(struct timespec lhs,
  71. struct timespec rhs)
  72. {
  73. struct timespec ts_delta;
  74. set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
  75. lhs.tv_nsec - rhs.tv_nsec);
  76. return ts_delta;
  77. }
  78. /*
  79. * Returns true if the timespec is norm, false if denorm:
  80. */
  81. #define timespec_valid(ts) \
  82. (((ts)->tv_sec >= 0) && (((unsigned long) (ts)->tv_nsec) < NSEC_PER_SEC))
  83. extern struct timespec xtime;
  84. extern struct timespec wall_to_monotonic;
  85. extern seqlock_t xtime_lock;
  86. extern void read_persistent_clock(struct timespec *ts);
  87. extern void read_boot_clock(struct timespec *ts);
  88. extern int update_persistent_clock(struct timespec now);
  89. extern int no_sync_cmos_clock __read_mostly;
  90. void timekeeping_init(void);
  91. extern int timekeeping_suspended;
  92. unsigned long get_seconds(void);
  93. struct timespec current_kernel_time(void);
  94. struct timespec __current_kernel_time(void); /* does not hold xtime_lock */
  95. struct timespec get_monotonic_coarse(void);
  96. #define CURRENT_TIME (current_kernel_time())
  97. #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 })
  98. /* Some architectures do not supply their own clocksource.
  99. * This is mainly the case in architectures that get their
  100. * inter-tick times by reading the counter on their interval
  101. * timer. Since these timers wrap every tick, they're not really
  102. * useful as clocksources. Wrapping them to act like one is possible
  103. * but not very efficient. So we provide a callout these arches
  104. * can implement for use with the jiffies clocksource to provide
  105. * finer then tick granular time.
  106. */
  107. #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
  108. extern u32 arch_gettimeoffset(void);
  109. #else
  110. static inline u32 arch_gettimeoffset(void) { return 0; }
  111. #endif
  112. extern void do_gettimeofday(struct timeval *tv);
  113. extern int do_settimeofday(struct timespec *tv);
  114. extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz);
  115. #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
  116. extern long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags);
  117. struct itimerval;
  118. extern int do_setitimer(int which, struct itimerval *value,
  119. struct itimerval *ovalue);
  120. extern unsigned int alarm_setitimer(unsigned int seconds);
  121. extern int do_getitimer(int which, struct itimerval *value);
  122. extern void getnstimeofday(struct timespec *tv);
  123. extern void getrawmonotonic(struct timespec *ts);
  124. extern void getboottime(struct timespec *ts);
  125. extern void monotonic_to_bootbased(struct timespec *ts);
  126. extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
  127. extern int timekeeping_valid_for_hres(void);
  128. extern u64 timekeeping_max_deferment(void);
  129. extern void update_wall_time(void);
  130. extern void timekeeping_leap_insert(int leapsecond);
  131. struct tms;
  132. extern void do_sys_times(struct tms *);
  133. /*
  134. * Similar to the struct tm in userspace <time.h>, but it needs to be here so
  135. * that the kernel source is self contained.
  136. */
  137. struct tm {
  138. /*
  139. * the number of seconds after the minute, normally in the range
  140. * 0 to 59, but can be up to 60 to allow for leap seconds
  141. */
  142. int tm_sec;
  143. /* the number of minutes after the hour, in the range 0 to 59*/
  144. int tm_min;
  145. /* the number of hours past midnight, in the range 0 to 23 */
  146. int tm_hour;
  147. /* the day of the month, in the range 1 to 31 */
  148. int tm_mday;
  149. /* the number of months since January, in the range 0 to 11 */
  150. int tm_mon;
  151. /* the number of years since 1900 */
  152. long tm_year;
  153. /* the number of days since Sunday, in the range 0 to 6 */
  154. int tm_wday;
  155. /* the number of days since January 1, in the range 0 to 365 */
  156. int tm_yday;
  157. };
  158. void time_to_tm(time_t totalsecs, int offset, struct tm *result);
  159. /**
  160. * timespec_to_ns - Convert timespec to nanoseconds
  161. * @ts: pointer to the timespec variable to be converted
  162. *
  163. * Returns the scalar nanosecond representation of the timespec
  164. * parameter.
  165. */
  166. static inline s64 timespec_to_ns(const struct timespec *ts)
  167. {
  168. return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
  169. }
  170. /**
  171. * timeval_to_ns - Convert timeval to nanoseconds
  172. * @ts: pointer to the timeval variable to be converted
  173. *
  174. * Returns the scalar nanosecond representation of the timeval
  175. * parameter.
  176. */
  177. static inline s64 timeval_to_ns(const struct timeval *tv)
  178. {
  179. return ((s64) tv->tv_sec * NSEC_PER_SEC) +
  180. tv->tv_usec * NSEC_PER_USEC;
  181. }
  182. /**
  183. * ns_to_timespec - Convert nanoseconds to timespec
  184. * @nsec: the nanoseconds value to be converted
  185. *
  186. * Returns the timespec representation of the nsec parameter.
  187. */
  188. extern struct timespec ns_to_timespec(const s64 nsec);
  189. /**
  190. * ns_to_timeval - Convert nanoseconds to timeval
  191. * @nsec: the nanoseconds value to be converted
  192. *
  193. * Returns the timeval representation of the nsec parameter.
  194. */
  195. extern struct timeval ns_to_timeval(const s64 nsec);
  196. /**
  197. * timespec_add_ns - Adds nanoseconds to a timespec
  198. * @a: pointer to timespec to be incremented
  199. * @ns: unsigned nanoseconds value to be added
  200. *
  201. * This must always be inlined because its used from the x86-64 vdso,
  202. * which cannot call other kernel functions.
  203. */
  204. static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
  205. {
  206. a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
  207. a->tv_nsec = ns;
  208. }
  209. #endif /* __KERNEL__ */
  210. #define NFDBITS __NFDBITS
  211. #define FD_SETSIZE __FD_SETSIZE
  212. #define FD_SET(fd,fdsetp) __FD_SET(fd,fdsetp)
  213. #define FD_CLR(fd,fdsetp) __FD_CLR(fd,fdsetp)
  214. #define FD_ISSET(fd,fdsetp) __FD_ISSET(fd,fdsetp)
  215. #define FD_ZERO(fdsetp) __FD_ZERO(fdsetp)
  216. /*
  217. * Names of the interval timers, and structure
  218. * defining a timer setting:
  219. */
  220. #define ITIMER_REAL 0
  221. #define ITIMER_VIRTUAL 1
  222. #define ITIMER_PROF 2
  223. struct itimerspec {
  224. struct timespec it_interval; /* timer period */
  225. struct timespec it_value; /* timer expiration */
  226. };
  227. struct itimerval {
  228. struct timeval it_interval; /* timer interval */
  229. struct timeval it_value; /* current value */
  230. };
  231. /*
  232. * The IDs of the various system clocks (for POSIX.1b interval timers):
  233. */
  234. #define CLOCK_REALTIME 0
  235. #define CLOCK_MONOTONIC 1
  236. #define CLOCK_PROCESS_CPUTIME_ID 2
  237. #define CLOCK_THREAD_CPUTIME_ID 3
  238. #define CLOCK_MONOTONIC_RAW 4
  239. #define CLOCK_REALTIME_COARSE 5
  240. #define CLOCK_MONOTONIC_COARSE 6
  241. /*
  242. * The IDs of various hardware clocks:
  243. */
  244. #define CLOCK_SGI_CYCLE 10
  245. #define MAX_CLOCKS 16
  246. #define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC)
  247. #define CLOCKS_MONO CLOCK_MONOTONIC
  248. /*
  249. * The various flags for setting POSIX.1b interval timers:
  250. */
  251. #define TIMER_ABSTIME 0x01
  252. #endif