/* * include/common/time.h * Time calculation functions and macros. * * Copyright (C) 2000-2011 Willy Tarreau - w@1wt.eu * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation, version 2.1 * exclusively. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _COMMON_TIME_H #define _COMMON_TIME_H #include #include #include #include #include #include /* eternity when exprimed in timeval */ #ifndef TV_ETERNITY #define TV_ETERNITY (~0UL) #endif /* eternity when exprimed in ms */ #ifndef TV_ETERNITY_MS #define TV_ETERNITY_MS (-1) #endif #define TIME_ETERNITY (TV_ETERNITY_MS) /* we want to be able to detect time jumps. Fix the maximum wait time to a low * value so that we know the time has changed if we wait longer. */ #define MAX_DELAY_MS 1000 /* returns the lowest delay amongst and , and respects TIME_ETERNITY */ #define MINTIME(old, new) (((new)<0)?(old):(((old)<0||(new)<(old))?(new):(old))) #define SETNOW(a) (*a=now) extern THREAD_LOCAL unsigned int curr_sec_ms; /* millisecond of current second (0..999) */ extern THREAD_LOCAL unsigned int ms_left_scaled; /* milliseconds left for current second (0..2^32-1) */ extern THREAD_LOCAL unsigned int curr_sec_ms_scaled; /* millisecond of current second (0..2^32-1) */ extern THREAD_LOCAL unsigned int now_ms; /* internal date in milliseconds (may wrap) */ extern THREAD_LOCAL unsigned int samp_time; /* total elapsed time over current sample */ extern THREAD_LOCAL unsigned int idle_time; /* total idle time over current sample */ extern THREAD_LOCAL unsigned int idle_pct; /* idle to total ratio over last sample (percent) */ extern THREAD_LOCAL struct timeval now; /* internal date is a monotonic function of real clock */ extern THREAD_LOCAL struct timeval date; /* the real current date */ extern struct timeval start_date; /* the process's start date */ extern THREAD_LOCAL struct timeval before_poll; /* system date before calling poll() */ extern THREAD_LOCAL struct timeval after_poll; /* system date after leaving poll() */ extern THREAD_LOCAL uint64_t prev_cpu_time; /* previous per thread CPU time */ extern THREAD_LOCAL uint64_t prev_mono_time; /* previous system wide monotonic time */ /**** exported functions *************************************************/ /* * adds ms to , set the result to and returns a pointer */ REGPRM3 struct timeval *tv_ms_add(struct timeval *tv, const struct timeval *from, int ms); /* * compares and modulo 1ms: returns 0 if equal, -1 if tv1 < tv2, 1 if tv1 > tv2 * Must not be used when either argument is eternity. Use tv_ms_cmp2() for that. */ REGPRM2 int tv_ms_cmp(const struct timeval *tv1, const struct timeval *tv2); /* * compares and modulo 1 ms: returns 0 if equal, -1 if tv1 < tv2, 1 if tv1 > tv2, * assuming that TV_ETERNITY is greater than everything. */ REGPRM2 int tv_ms_cmp2(const struct timeval *tv1, const struct timeval *tv2); /* Updates the current thread's statistics about stolen CPU time. The unit for * is half-milliseconds. */ REGPRM1 void report_stolen_time(uint64_t stolen); /**** general purpose functions and macros *******************************/ /* tv_now: sets to the current time */ REGPRM1 static inline struct timeval *tv_now(struct timeval *tv) { gettimeofday(tv, NULL); return tv; } /* tv_udpate_date: sets to system time, and sets to something as * close as possible to real time, following a monotonic function. The main * principle consists in detecting backwards and forwards time jumps and adjust * an offset to correct them. This function should be called only once after * each poll. The poll's timeout should be passed in , and the return * value in (a non-zero value means that we have not expired the * timeout). */ REGPRM2 void tv_update_date(int max_wait, int interrupted); /* * sets a struct timeval to its highest value so that it can never happen * note that only tv_usec is necessary to detect it since a tv_usec > 999999 * is normally not possible. */ REGPRM1 static inline struct timeval *tv_eternity(struct timeval *tv) { tv->tv_sec = (typeof(tv->tv_sec))TV_ETERNITY; tv->tv_usec = (typeof(tv->tv_usec))TV_ETERNITY; return tv; } /* * sets a struct timeval to 0 * */ REGPRM1 static inline struct timeval *tv_zero(struct timeval *tv) { tv->tv_sec = tv->tv_usec = 0; return tv; } /* * returns non null if tv is [eternity], otherwise 0. */ #define tv_iseternity(tv) ((tv)->tv_usec == (typeof((tv)->tv_usec))TV_ETERNITY) /* * returns 0 if tv is [eternity], otherwise non-zero. */ #define tv_isset(tv) ((tv)->tv_usec != (typeof((tv)->tv_usec))TV_ETERNITY) /* * returns non null if tv is [0], otherwise 0. */ #define tv_iszero(tv) (((tv)->tv_sec | (tv)->tv_usec) == 0) /* * Converts a struct timeval to a number of milliseconds. */ REGPRM1 static inline unsigned long __tv_to_ms(const struct timeval *tv) { unsigned long ret; ret = tv->tv_sec * 1000; ret += tv->tv_usec / 1000; return ret; } /* * Converts a struct timeval to a number of milliseconds. */ REGPRM2 static inline struct timeval * __tv_from_ms(struct timeval *tv, unsigned long ms) { tv->tv_sec = ms / 1000; tv->tv_usec = (ms % 1000) * 1000; return tv; } /* Return a number of 1024Hz ticks between 0 and 1023 for input number of * usecs between 0 and 999999. This function has been optimized to remove * any divide and multiply, as it is completely optimized away by the compiler * on CPUs which don't have a fast multiply. Its avg error rate is 305 ppm, * which is almost twice as low as a direct usec to ms conversion. This version * also has the benefit of returning 1024 for 1000000. */ REGPRM1 static inline unsigned int __usec_to_1024th(unsigned int usec) { return (usec * 1073 + 742516) >> 20; } /**** comparison functions and macros ***********************************/ /* tv_cmp: compares and : returns 0 if equal, -1 if tv1 < tv2, 1 if tv1 > tv2. */ REGPRM2 static inline int __tv_cmp(const struct timeval *tv1, const struct timeval *tv2) { if ((unsigned)tv1->tv_sec < (unsigned)tv2->tv_sec) return -1; else if ((unsigned)tv1->tv_sec > (unsigned)tv2->tv_sec) return 1; else if ((unsigned)tv1->tv_usec < (unsigned)tv2->tv_usec) return -1; else if ((unsigned)tv1->tv_usec > (unsigned)tv2->tv_usec) return 1; else return 0; } /* tv_iseq: compares and : returns 1 if tv1 == tv2, otherwise 0 */ #define tv_iseq __tv_iseq REGPRM2 static inline int __tv_iseq(const struct timeval *tv1, const struct timeval *tv2) { return ((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec) && ((unsigned)tv1->tv_usec == (unsigned)tv2->tv_usec); } /* tv_isgt: compares and : returns 1 if tv1 > tv2, otherwise 0 */ #define tv_isgt _tv_isgt REGPRM2 int _tv_isgt(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline int __tv_isgt(const struct timeval *tv1, const struct timeval *tv2) { return ((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec) ? ((unsigned)tv1->tv_usec > (unsigned)tv2->tv_usec) : ((unsigned)tv1->tv_sec > (unsigned)tv2->tv_sec); } /* tv_isge: compares and : returns 1 if tv1 >= tv2, otherwise 0 */ #define tv_isge __tv_isge REGPRM2 static inline int __tv_isge(const struct timeval *tv1, const struct timeval *tv2) { return ((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec) ? ((unsigned)tv1->tv_usec >= (unsigned)tv2->tv_usec) : ((unsigned)tv1->tv_sec > (unsigned)tv2->tv_sec); } /* tv_islt: compares and : returns 1 if tv1 < tv2, otherwise 0 */ #define tv_islt __tv_islt REGPRM2 static inline int __tv_islt(const struct timeval *tv1, const struct timeval *tv2) { return ((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec) ? ((unsigned)tv1->tv_usec < (unsigned)tv2->tv_usec) : ((unsigned)tv1->tv_sec < (unsigned)tv2->tv_sec); } /* tv_isle: compares and : returns 1 if tv1 <= tv2, otherwise 0 */ #define tv_isle _tv_isle REGPRM2 int _tv_isle(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline int __tv_isle(const struct timeval *tv1, const struct timeval *tv2) { return ((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec) ? ((unsigned)tv1->tv_usec <= (unsigned)tv2->tv_usec) : ((unsigned)tv1->tv_sec < (unsigned)tv2->tv_sec); } /* * compares and modulo 1ms: returns 0 if equal, -1 if tv1 < tv2, 1 if tv1 > tv2 * Must not be used when either argument is eternity. Use tv_ms_cmp2() for that. */ #define tv_ms_cmp _tv_ms_cmp REGPRM2 int _tv_ms_cmp(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline int __tv_ms_cmp(const struct timeval *tv1, const struct timeval *tv2) { if ((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec) { if ((unsigned)tv2->tv_usec >= (unsigned)tv1->tv_usec + 1000) return -1; else if ((unsigned)tv1->tv_usec >= (unsigned)tv2->tv_usec + 1000) return 1; else return 0; } else if (((unsigned)tv2->tv_sec > (unsigned)tv1->tv_sec + 1) || (((unsigned)tv2->tv_sec == (unsigned)tv1->tv_sec + 1) && ((unsigned)tv2->tv_usec + 1000000 >= (unsigned)tv1->tv_usec + 1000))) return -1; else if (((unsigned)tv1->tv_sec > (unsigned)tv2->tv_sec + 1) || (((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec + 1) && ((unsigned)tv1->tv_usec + 1000000 >= (unsigned)tv2->tv_usec + 1000))) return 1; else return 0; } /* * compares and modulo 1 ms: returns 0 if equal, -1 if tv1 < tv2, 1 if tv1 > tv2, * assuming that TV_ETERNITY is greater than everything. */ #define tv_ms_cmp2 _tv_ms_cmp2 REGPRM2 int _tv_ms_cmp2(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline int __tv_ms_cmp2(const struct timeval *tv1, const struct timeval *tv2) { if (tv_iseternity(tv1)) if (tv_iseternity(tv2)) return 0; /* same */ else return 1; /* tv1 later than tv2 */ else if (tv_iseternity(tv2)) return -1; /* tv2 later than tv1 */ return tv_ms_cmp(tv1, tv2); } /* * compares and modulo 1 ms: returns 1 if tv1 <= tv2, 0 if tv1 > tv2, * assuming that TV_ETERNITY is greater than everything. Returns 0 if tv1 is * TV_ETERNITY, and always assumes that tv2 != TV_ETERNITY. Designed to replace * occurrences of (tv_ms_cmp2(tv,now) <= 0). */ #define tv_ms_le2 _tv_ms_le2 REGPRM2 int _tv_ms_le2(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline int __tv_ms_le2(const struct timeval *tv1, const struct timeval *tv2) { if (likely((unsigned)tv1->tv_sec > (unsigned)tv2->tv_sec + 1)) return 0; if (likely((unsigned)tv1->tv_sec < (unsigned)tv2->tv_sec)) return 1; if (likely((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec)) { if ((unsigned)tv2->tv_usec >= (unsigned)tv1->tv_usec + 1000) return 1; else return 0; } if (unlikely(((unsigned)tv1->tv_sec == (unsigned)tv2->tv_sec + 1) && ((unsigned)tv1->tv_usec + 1000000 >= (unsigned)tv2->tv_usec + 1000))) return 0; else return 1; } /**** operators **********************************************************/ /* * Returns the time in ms elapsed between tv1 and tv2, assuming that tv1<=tv2. * Must not be used when either argument is eternity. */ #define tv_ms_elapsed __tv_ms_elapsed REGPRM2 unsigned long _tv_ms_elapsed(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline unsigned long __tv_ms_elapsed(const struct timeval *tv1, const struct timeval *tv2) { unsigned long ret; ret = ((signed long)(tv2->tv_sec - tv1->tv_sec)) * 1000; ret += ((signed long)(tv2->tv_usec - tv1->tv_usec)) / 1000; return ret; } /* * returns the remaining time between tv1=now and event=tv2 * if tv2 is passed, 0 is returned. * Must not be used when either argument is eternity. */ #define tv_ms_remain __tv_ms_remain REGPRM2 unsigned long _tv_ms_remain(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline unsigned long __tv_ms_remain(const struct timeval *tv1, const struct timeval *tv2) { if (tv_ms_cmp(tv1, tv2) >= 0) return 0; /* event elapsed */ return __tv_ms_elapsed(tv1, tv2); } /* * returns the remaining time between tv1=now and event=tv2 * if tv2 is passed, 0 is returned. * Returns TIME_ETERNITY if tv2 is eternity. */ #define tv_ms_remain2 _tv_ms_remain2 REGPRM2 unsigned long _tv_ms_remain2(const struct timeval *tv1, const struct timeval *tv2); REGPRM2 static inline unsigned long __tv_ms_remain2(const struct timeval *tv1, const struct timeval *tv2) { if (tv_iseternity(tv2)) return TIME_ETERNITY; return tv_ms_remain(tv1, tv2); } /* * adds to , set the result to and returns a pointer */ #define tv_add _tv_add REGPRM3 struct timeval *_tv_add(struct timeval *tv, const struct timeval *from, const struct timeval *inc); REGPRM3 static inline struct timeval *__tv_add(struct timeval *tv, const struct timeval *from, const struct timeval *inc) { tv->tv_usec = from->tv_usec + inc->tv_usec; tv->tv_sec = from->tv_sec + inc->tv_sec; if (tv->tv_usec >= 1000000) { tv->tv_usec -= 1000000; tv->tv_sec++; } return tv; } /* * If is set, then add it to and set the result to , then * return 1, otherwise return 0. It is meant to be used in if conditions. */ #define tv_add_ifset _tv_add_ifset REGPRM3 int _tv_add_ifset(struct timeval *tv, const struct timeval *from, const struct timeval *inc); REGPRM3 static inline int __tv_add_ifset(struct timeval *tv, const struct timeval *from, const struct timeval *inc) { if (tv_iseternity(inc)) return 0; tv->tv_usec = from->tv_usec + inc->tv_usec; tv->tv_sec = from->tv_sec + inc->tv_sec; if (tv->tv_usec >= 1000000) { tv->tv_usec -= 1000000; tv->tv_sec++; } return 1; } /* * adds to and returns a pointer */ REGPRM2 static inline struct timeval *__tv_add2(struct timeval *tv, const struct timeval *inc) { tv->tv_usec += inc->tv_usec; tv->tv_sec += inc->tv_sec; if (tv->tv_usec >= 1000000) { tv->tv_usec -= 1000000; tv->tv_sec++; } return tv; } /* * Computes the remaining time between tv1=now and event=tv2. if tv2 is passed, * 0 is returned. The result is stored into tv. */ #define tv_remain _tv_remain REGPRM3 struct timeval *_tv_remain(const struct timeval *tv1, const struct timeval *tv2, struct timeval *tv); REGPRM3 static inline struct timeval *__tv_remain(const struct timeval *tv1, const struct timeval *tv2, struct timeval *tv) { tv->tv_usec = tv2->tv_usec - tv1->tv_usec; tv->tv_sec = tv2->tv_sec - tv1->tv_sec; if ((signed)tv->tv_sec > 0) { if ((signed)tv->tv_usec < 0) { tv->tv_usec += 1000000; tv->tv_sec--; } } else if (tv->tv_sec == 0) { if ((signed)tv->tv_usec < 0) tv->tv_usec = 0; } else { tv->tv_sec = 0; tv->tv_usec = 0; } return tv; } /* * Computes the remaining time between tv1=now and event=tv2. if tv2 is passed, * 0 is returned. The result is stored into tv. Returns ETERNITY if tv2 is * eternity. */ #define tv_remain2 _tv_remain2 REGPRM3 struct timeval *_tv_remain2(const struct timeval *tv1, const struct timeval *tv2, struct timeval *tv); REGPRM3 static inline struct timeval *__tv_remain2(const struct timeval *tv1, const struct timeval *tv2, struct timeval *tv) { if (tv_iseternity(tv2)) return tv_eternity(tv); return __tv_remain(tv1, tv2, tv); } /* * adds ms to , set the result to and returns a pointer */ #define tv_ms_add _tv_ms_add REGPRM3 struct timeval *_tv_ms_add(struct timeval *tv, const struct timeval *from, int ms); REGPRM3 static inline struct timeval *__tv_ms_add(struct timeval *tv, const struct timeval *from, int ms) { tv->tv_usec = from->tv_usec + (ms % 1000) * 1000; tv->tv_sec = from->tv_sec + (ms / 1000); while (tv->tv_usec >= 1000000) { tv->tv_usec -= 1000000; tv->tv_sec++; } return tv; } /* * compares and : returns 1 if is before , otherwise 0. * This should be very fast because it's used in schedulers. * It has been optimized to return 1 (so call it in a loop which continues * as long as tv1<=tv2) */ #define tv_isbefore(tv1, tv2) \ (unlikely((unsigned)(tv1)->tv_sec < (unsigned)(tv2)->tv_sec) ? 1 : \ (unlikely((unsigned)(tv1)->tv_sec > (unsigned)(tv2)->tv_sec) ? 0 : \ unlikely((unsigned)(tv1)->tv_usec < (unsigned)(tv2)->tv_usec))) /* * returns the first event between and into . * a zero tv is ignored. is returned. If is known * to be the same as or , it is recommended to use * tv_bound instead. */ #define tv_min(tvmin, tv1, tv2) ({ \ if (tv_isbefore(tv1, tv2)) { \ *tvmin = *tv1; \ } \ else { \ *tvmin = *tv2; \ } \ tvmin; \ }) /* * returns the first event between and into . * a zero tv is ignored. is returned. This function has been * optimized to be called as tv_min(a,a,b) or tv_min(b,a,b). */ #define tv_bound(tv1, tv2) ({ \ if (tv_isbefore(tv2, tv1)) \ *tv1 = *tv2; \ tv1; \ }) /* returns the system's monotonic time in nanoseconds if supported, otherwise zero */ static inline uint64_t now_mono_time() { #if defined(_POSIX_TIMERS) && defined(_POSIX_MONOTONIC_CLOCK) struct timespec ts; clock_gettime(CLOCK_MONOTONIC, &ts); return ts.tv_sec * 1000000000ULL + ts.tv_nsec; #else return 0; #endif } /* returns the current thread's cumulated CPU time in nanoseconds if supported, otherwise zero */ static inline uint64_t now_cpu_time() { #if defined(_POSIX_TIMERS) && defined(_POSIX_THREAD_CPUTIME) struct timespec ts; clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts); return ts.tv_sec * 1000000000ULL + ts.tv_nsec; #else return 0; #endif } /* Update the idle time value twice a second, to be called after * tv_update_date() when called after poll(). It relies on to be * updated to the system time before calling poll(). */ static inline void measure_idle() { /* Let's compute the idle to work ratio. We worked between after_poll * and before_poll, and slept between before_poll and date. The idle_pct * is updated at most twice every second. Note that the current second * rarely changes so we avoid a multiply when not needed. */ int delta; if ((delta = date.tv_sec - before_poll.tv_sec)) delta *= 1000000; idle_time += delta + (date.tv_usec - before_poll.tv_usec); if ((delta = date.tv_sec - after_poll.tv_sec)) delta *= 1000000; samp_time += delta + (date.tv_usec - after_poll.tv_usec); after_poll.tv_sec = date.tv_sec; after_poll.tv_usec = date.tv_usec; if (samp_time < 500000) return; idle_pct = (100 * idle_time + samp_time / 2) / samp_time; idle_time = samp_time = 0; } /* Collect date and time information before calling poll(). This will be used * to count the run time of the past loop and the sleep time of the next poll. */ static inline void tv_entering_poll() { uint64_t new_mono_time; uint64_t new_cpu_time; int64_t stolen; new_cpu_time = now_cpu_time(); new_mono_time = now_mono_time(); if (prev_cpu_time && prev_mono_time) { new_cpu_time -= prev_cpu_time; new_mono_time -= prev_mono_time; stolen = new_mono_time - new_cpu_time; if (stolen >= 500000) { stolen /= 500000; /* more than half a millisecond difference might * indicate an undesired preemption. */ report_stolen_time(stolen); } } gettimeofday(&before_poll, NULL); } /* Collect date and time information after leaving poll(). must be * set to the maximum sleep time passed to poll (in milliseconds), and * must be zero if the poller reached the timeout or non-zero * otherwise, which generally is provided by the poller's return value. */ static inline void tv_leaving_poll(int timeout, int interrupted) { tv_update_date(timeout, interrupted); measure_idle(); prev_cpu_time = now_cpu_time(); prev_mono_time = now_mono_time(); } #endif /* _COMMON_TIME_H */ /* * Local variables: * c-indent-level: 8 * c-basic-offset: 8 * End: */