time.h 7.2 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, long 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 unsigned long read_persistent_clock(void);
  87. extern int update_persistent_clock(struct timespec now);
  88. extern int no_sync_cmos_clock __read_mostly;
  89. void timekeeping_init(void);
  90. extern int timekeeping_suspended;
  91. unsigned long get_seconds(void);
  92. struct timespec current_kernel_time(void);
  93. #define CURRENT_TIME (current_kernel_time())
  94. #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 })
  95. /* Some architectures do not supply their own clocksource.
  96. * This is mainly the case in architectures that get their
  97. * inter-tick times by reading the counter on their interval
  98. * timer. Since these timers wrap every tick, they're not really
  99. * useful as clocksources. Wrapping them to act like one is possible
  100. * but not very efficient. So we provide a callout these arches
  101. * can implement for use with the jiffies clocksource to provide
  102. * finer then tick granular time.
  103. */
  104. #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
  105. extern u32 arch_gettimeoffset(void);
  106. #else
  107. static inline u32 arch_gettimeoffset(void) { return 0; }
  108. #endif
  109. extern void do_gettimeofday(struct timeval *tv);
  110. extern int do_settimeofday(struct timespec *tv);
  111. extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz);
  112. #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
  113. extern long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags);
  114. struct itimerval;
  115. extern int do_setitimer(int which, struct itimerval *value,
  116. struct itimerval *ovalue);
  117. extern unsigned int alarm_setitimer(unsigned int seconds);
  118. extern int do_getitimer(int which, struct itimerval *value);
  119. extern void getnstimeofday(struct timespec *tv);
  120. extern void getrawmonotonic(struct timespec *ts);
  121. extern void getboottime(struct timespec *ts);
  122. extern void monotonic_to_bootbased(struct timespec *ts);
  123. extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
  124. extern int timekeeping_valid_for_hres(void);
  125. extern void update_wall_time(void);
  126. extern void update_xtime_cache(u64 nsec);
  127. struct tms;
  128. extern void do_sys_times(struct tms *);
  129. /**
  130. * timespec_to_ns - Convert timespec to nanoseconds
  131. * @ts: pointer to the timespec variable to be converted
  132. *
  133. * Returns the scalar nanosecond representation of the timespec
  134. * parameter.
  135. */
  136. static inline s64 timespec_to_ns(const struct timespec *ts)
  137. {
  138. return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
  139. }
  140. /**
  141. * timeval_to_ns - Convert timeval to nanoseconds
  142. * @ts: pointer to the timeval variable to be converted
  143. *
  144. * Returns the scalar nanosecond representation of the timeval
  145. * parameter.
  146. */
  147. static inline s64 timeval_to_ns(const struct timeval *tv)
  148. {
  149. return ((s64) tv->tv_sec * NSEC_PER_SEC) +
  150. tv->tv_usec * NSEC_PER_USEC;
  151. }
  152. /**
  153. * ns_to_timespec - Convert nanoseconds to timespec
  154. * @nsec: the nanoseconds value to be converted
  155. *
  156. * Returns the timespec representation of the nsec parameter.
  157. */
  158. extern struct timespec ns_to_timespec(const s64 nsec);
  159. /**
  160. * ns_to_timeval - Convert nanoseconds to timeval
  161. * @nsec: the nanoseconds value to be converted
  162. *
  163. * Returns the timeval representation of the nsec parameter.
  164. */
  165. extern struct timeval ns_to_timeval(const s64 nsec);
  166. /**
  167. * timespec_add_ns - Adds nanoseconds to a timespec
  168. * @a: pointer to timespec to be incremented
  169. * @ns: unsigned nanoseconds value to be added
  170. *
  171. * This must always be inlined because its used from the x86-64 vdso,
  172. * which cannot call other kernel functions.
  173. */
  174. static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
  175. {
  176. a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
  177. a->tv_nsec = ns;
  178. }
  179. #endif /* __KERNEL__ */
  180. #define NFDBITS __NFDBITS
  181. #define FD_SETSIZE __FD_SETSIZE
  182. #define FD_SET(fd,fdsetp) __FD_SET(fd,fdsetp)
  183. #define FD_CLR(fd,fdsetp) __FD_CLR(fd,fdsetp)
  184. #define FD_ISSET(fd,fdsetp) __FD_ISSET(fd,fdsetp)
  185. #define FD_ZERO(fdsetp) __FD_ZERO(fdsetp)
  186. /*
  187. * Names of the interval timers, and structure
  188. * defining a timer setting:
  189. */
  190. #define ITIMER_REAL 0
  191. #define ITIMER_VIRTUAL 1
  192. #define ITIMER_PROF 2
  193. struct itimerspec {
  194. struct timespec it_interval; /* timer period */
  195. struct timespec it_value; /* timer expiration */
  196. };
  197. struct itimerval {
  198. struct timeval it_interval; /* timer interval */
  199. struct timeval it_value; /* current value */
  200. };
  201. /*
  202. * The IDs of the various system clocks (for POSIX.1b interval timers):
  203. */
  204. #define CLOCK_REALTIME 0
  205. #define CLOCK_MONOTONIC 1
  206. #define CLOCK_PROCESS_CPUTIME_ID 2
  207. #define CLOCK_THREAD_CPUTIME_ID 3
  208. #define CLOCK_MONOTONIC_RAW 4
  209. /*
  210. * The IDs of various hardware clocks:
  211. */
  212. #define CLOCK_SGI_CYCLE 10
  213. #define MAX_CLOCKS 16
  214. #define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC)
  215. #define CLOCKS_MONO CLOCK_MONOTONIC
  216. /*
  217. * The various flags for setting POSIX.1b interval timers:
  218. */
  219. #define TIMER_ABSTIME 0x01
  220. #endif