X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Flinux%2Ftime.h;h=0cd696cee998c0ed24d28ead62335160bc4e47a0;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=d24a690cbd04dabbe813984b0e613bc92a3df54c;hpb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;p=linux-2.6.git diff --git a/include/linux/time.h b/include/linux/time.h index d24a690cb..0cd696cee 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -1,16 +1,19 @@ #ifndef _LINUX_TIME_H #define _LINUX_TIME_H -#include #include +#ifdef __KERNEL__ +# include +#endif + #ifndef _STRUCT_TIMESPEC #define _STRUCT_TIMESPEC struct timespec { time_t tv_sec; /* seconds */ long tv_nsec; /* nanoseconds */ }; -#endif /* _STRUCT_TIMESPEC */ +#endif struct timeval { time_t tv_sec; /* seconds */ @@ -24,346 +27,124 @@ struct timezone { #ifdef __KERNEL__ -#include -#include -#include -#include -#ifndef div_long_long_rem - -#define div_long_long_rem(dividend,divisor,remainder) ({ \ - u64 result = dividend; \ - *remainder = do_div(result,divisor); \ - result; }) - -#endif +/* Parameters used to convert the timespec values: */ +#define MSEC_PER_SEC 1000L +#define USEC_PER_SEC 1000000L +#define NSEC_PER_SEC 1000000000L +#define NSEC_PER_USEC 1000L -/* - * Have the 32 bit jiffies value wrap 5 minutes after boot - * so jiffies wrap bugs show up earlier. - */ -#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-300*HZ)) - -/* - * Change timeval to jiffies, trying to avoid the - * most obvious overflows.. - * - * And some not so obvious. - * - * Note that we don't want to return MAX_LONG, because - * for various timeout reasons we often end up having - * to wait "jiffies+1" in order to guarantee that we wait - * at _least_ "jiffies" - so "jiffies+1" had better still - * be positive. - */ -#define MAX_JIFFY_OFFSET ((~0UL >> 1)-1) - -/* Parameters used to convert the timespec values */ -#ifndef USEC_PER_SEC -#define USEC_PER_SEC (1000000L) -#endif - -#ifndef NSEC_PER_SEC -#define NSEC_PER_SEC (1000000000L) -#endif - -#ifndef NSEC_PER_USEC -#define NSEC_PER_USEC (1000L) -#endif - -/* - * We want to do realistic conversions of time so we need to use the same - * values the update wall clock code uses as the jiffies size. This value - * is: TICK_NSEC (which is defined in timex.h). This - * is a constant and is in nanoseconds. We will used scaled math - * with a set of scales defined here as SEC_JIFFIE_SC, USEC_JIFFIE_SC and - * NSEC_JIFFIE_SC. Note that these defines contain nothing but - * constants and so are computed at compile time. SHIFT_HZ (computed in - * timex.h) adjusts the scaling for different HZ values. - - * Scaled math??? What is that? - * - * Scaled math is a way to do integer math on values that would, - * otherwise, either overflow, underflow, or cause undesired div - * instructions to appear in the execution path. In short, we "scale" - * up the operands so they take more bits (more precision, less - * underflow), do the desired operation and then "scale" the result back - * by the same amount. If we do the scaling by shifting we avoid the - * costly mpy and the dastardly div instructions. - - * Suppose, for example, we want to convert from seconds to jiffies - * where jiffies is defined in nanoseconds as NSEC_PER_JIFFIE. The - * simple math is: jiff = (sec * NSEC_PER_SEC) / NSEC_PER_JIFFIE; We - * observe that (NSEC_PER_SEC / NSEC_PER_JIFFIE) is a constant which we - * might calculate at compile time, however, the result will only have - * about 3-4 bits of precision (less for smaller values of HZ). - * - * So, we scale as follows: - * jiff = (sec) * (NSEC_PER_SEC / NSEC_PER_JIFFIE); - * jiff = ((sec) * ((NSEC_PER_SEC * SCALE)/ NSEC_PER_JIFFIE)) / SCALE; - * Then we make SCALE a power of two so: - * jiff = ((sec) * ((NSEC_PER_SEC << SCALE)/ NSEC_PER_JIFFIE)) >> SCALE; - * Now we define: - * #define SEC_CONV = ((NSEC_PER_SEC << SCALE)/ NSEC_PER_JIFFIE)) - * jiff = (sec * SEC_CONV) >> SCALE; - * - * Often the math we use will expand beyond 32-bits so we tell C how to - * do this and pass the 64-bit result of the mpy through the ">> SCALE" - * which should take the result back to 32-bits. We want this expansion - * to capture as much precision as possible. At the same time we don't - * want to overflow so we pick the SCALE to avoid this. In this file, - * that means using a different scale for each range of HZ values (as - * defined in timex.h). - * - * For those who want to know, gcc will give a 64-bit result from a "*" - * operator if the result is a long long AND at least one of the - * operands is cast to long long (usually just prior to the "*" so as - * not to confuse it into thinking it really has a 64-bit operand, - * which, buy the way, it can do, but it take more code and at least 2 - * mpys). - - * We also need to be aware that one second in nanoseconds is only a - * couple of bits away from overflowing a 32-bit word, so we MUST use - * 64-bits to get the full range time in nanoseconds. - - */ - -/* - * Here are the scales we will use. One for seconds, nanoseconds and - * microseconds. - * - * Within the limits of cpp we do a rough cut at the SEC_JIFFIE_SC and - * check if the sign bit is set. If not, we bump the shift count by 1. - * (Gets an extra bit of precision where we can use it.) - * We know it is set for HZ = 1024 and HZ = 100 not for 1000. - * Haven't tested others. - - * Limits of cpp (for #if expressions) only long (no long long), but - * then we only need the most signicant bit. - */ - -#define SEC_JIFFIE_SC (31 - SHIFT_HZ) -#if !((((NSEC_PER_SEC << 2) / TICK_NSEC) << (SEC_JIFFIE_SC - 2)) & 0x80000000) -#undef SEC_JIFFIE_SC -#define SEC_JIFFIE_SC (32 - SHIFT_HZ) -#endif -#define NSEC_JIFFIE_SC (SEC_JIFFIE_SC + 29) -#define USEC_JIFFIE_SC (SEC_JIFFIE_SC + 19) -#define SEC_CONVERSION ((unsigned long)((((u64)NSEC_PER_SEC << SEC_JIFFIE_SC) +\ - TICK_NSEC -1) / (u64)TICK_NSEC)) - -#define NSEC_CONVERSION ((unsigned long)((((u64)1 << NSEC_JIFFIE_SC) +\ - TICK_NSEC -1) / (u64)TICK_NSEC)) -#define USEC_CONVERSION \ - ((unsigned long)((((u64)NSEC_PER_USEC << USEC_JIFFIE_SC) +\ - TICK_NSEC -1) / (u64)TICK_NSEC)) -/* - * USEC_ROUND is used in the timeval to jiffie conversion. See there - * for more details. It is the scaled resolution rounding value. Note - * that it is a 64-bit value. Since, when it is applied, we are already - * in jiffies (albit scaled), it is nothing but the bits we will shift - * off. - */ -#define USEC_ROUND (u64)(((u64)1 << USEC_JIFFIE_SC) - 1) -/* - * The maximum jiffie value is (MAX_INT >> 1). Here we translate that - * into seconds. The 64-bit case will overflow if we are not careful, - * so use the messy SH_DIV macro to do it. Still all constants. - */ -#if BITS_PER_LONG < 64 -# define MAX_SEC_IN_JIFFIES \ - (long)((u64)((u64)MAX_JIFFY_OFFSET * TICK_NSEC) / NSEC_PER_SEC) -#else /* take care of overflow on 64 bits machines */ -# define MAX_SEC_IN_JIFFIES \ - (SH_DIV((MAX_JIFFY_OFFSET >> SEC_JIFFIE_SC) * TICK_NSEC, NSEC_PER_SEC, 1) - 1) - -#endif - -/* - * Convert jiffies to milliseconds and back. - * - * Avoid unnecessary multiplications/divisions in the - * two most common HZ cases: - */ -static inline unsigned int jiffies_to_msecs(const unsigned long j) -{ -#if HZ <= 1000 && !(1000 % HZ) - return (1000 / HZ) * j; -#elif HZ > 1000 && !(HZ % 1000) - return (j + (HZ / 1000) - 1)/(HZ / 1000); -#else - return (j * 1000) / HZ; -#endif -} -static inline unsigned long msecs_to_jiffies(const unsigned int m) +static inline int timespec_equal(struct timespec *a, struct timespec *b) { -#if HZ <= 1000 && !(1000 % HZ) - return (m + (1000 / HZ) - 1) / (1000 / HZ); -#elif HZ > 1000 && !(HZ % 1000) - return m * (HZ / 1000); -#else - return (m * HZ + 999) / 1000; -#endif + return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec); } /* - * The TICK_NSEC - 1 rounds up the value to the next resolution. Note - * that a remainder subtract here would not do the right thing as the - * resolution values don't fall on second boundries. I.e. the line: - * nsec -= nsec % TICK_NSEC; is NOT a correct resolution rounding. - * - * Rather, we just shift the bits off the right. - * - * The >> (NSEC_JIFFIE_SC - SEC_JIFFIE_SC) converts the scaled nsec - * value to a scaled second value. + * lhs < rhs: return <0 + * lhs == rhs: return 0 + * lhs > rhs: return >0 */ -static __inline__ unsigned long -timespec_to_jiffies(const struct timespec *value) -{ - unsigned long sec = value->tv_sec; - long nsec = value->tv_nsec + TICK_NSEC - 1; - - if (sec >= MAX_SEC_IN_JIFFIES){ - sec = MAX_SEC_IN_JIFFIES; - nsec = 0; - } - return (((u64)sec * SEC_CONVERSION) + - (((u64)nsec * NSEC_CONVERSION) >> - (NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC; - -} - -static __inline__ void -jiffies_to_timespec(const unsigned long jiffies, struct timespec *value) +static inline int timespec_compare(struct timespec *lhs, struct timespec *rhs) { - /* - * Convert jiffies to nanoseconds and separate with - * one divide. - */ - u64 nsec = (u64)jiffies * TICK_NSEC; - value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &value->tv_nsec); + if (lhs->tv_sec < rhs->tv_sec) + return -1; + if (lhs->tv_sec > rhs->tv_sec) + return 1; + return lhs->tv_nsec - rhs->tv_nsec; } -/* Same for "timeval" - * - * Well, almost. The problem here is that the real system resolution is - * in nanoseconds and the value being converted is in micro seconds. - * Also for some machines (those that use HZ = 1024, in-particular), - * there is a LARGE error in the tick size in microseconds. - - * The solution we use is to do the rounding AFTER we convert the - * microsecond part. Thus the USEC_ROUND, the bits to be shifted off. - * Instruction wise, this should cost only an additional add with carry - * instruction above the way it was done above. - */ -static __inline__ unsigned long -timeval_to_jiffies(const struct timeval *value) +static inline int timeval_compare(struct timeval *lhs, struct timeval *rhs) { - unsigned long sec = value->tv_sec; - long usec = value->tv_usec; - - if (sec >= MAX_SEC_IN_JIFFIES){ - sec = MAX_SEC_IN_JIFFIES; - usec = 0; - } - return (((u64)sec * SEC_CONVERSION) + - (((u64)usec * USEC_CONVERSION + USEC_ROUND) >> - (USEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC; + if (lhs->tv_sec < rhs->tv_sec) + return -1; + if (lhs->tv_sec > rhs->tv_sec) + return 1; + return lhs->tv_usec - rhs->tv_usec; } -static __inline__ void -jiffies_to_timeval(const unsigned long jiffies, struct timeval *value) -{ - /* - * Convert jiffies to nanoseconds and separate with - * one divide. - */ - u64 nsec = (u64)jiffies * TICK_NSEC; - value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &value->tv_usec); - value->tv_usec /= NSEC_PER_USEC; -} +extern unsigned long mktime(const unsigned int year, const unsigned int mon, + const unsigned int day, const unsigned int hour, + const unsigned int min, const unsigned int sec); -static __inline__ int timespec_equal(struct timespec *a, struct timespec *b) -{ - return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec); -} +extern void set_normalized_timespec(struct timespec *ts, time_t sec, long nsec); -/* Converts Gregorian date to seconds since 1970-01-01 00:00:00. - * Assumes input in normal date format, i.e. 1980-12-31 23:59:59 - * => year=1980, mon=12, day=31, hour=23, min=59, sec=59. - * - * [For the Julian calendar (which was used in Russia before 1917, - * Britain & colonies before 1752, anywhere else before 1582, - * and is still in use by some communities) leave out the - * -year/100+year/400 terms, and add 10.] - * - * This algorithm was first published by Gauss (I think). - * - * WARNING: this function will overflow on 2106-02-07 06:28:16 on - * machines were long is 32-bit! (However, as time_t is signed, we - * will already get problems at other places on 2038-01-19 03:14:08) +/* + * Returns true if the timespec is norm, false if denorm: */ -static inline unsigned long -mktime (unsigned int year, unsigned int mon, - unsigned int day, unsigned int hour, - unsigned int min, unsigned int sec) -{ - if (0 >= (int) (mon -= 2)) { /* 1..12 -> 11,12,1..10 */ - mon += 12; /* Puts Feb last since it has leap day */ - year -= 1; - } - - return ((( - (unsigned long) (year/4 - year/100 + year/400 + 367*mon/12 + day) + - year*365 - 719499 - )*24 + hour /* now have hours */ - )*60 + min /* now have minutes */ - )*60 + sec; /* finally seconds */ -} +#define timespec_valid(ts) \ + (((ts)->tv_sec >= 0) && (((unsigned long) (ts)->tv_nsec) < NSEC_PER_SEC)) extern struct timespec xtime; extern struct timespec wall_to_monotonic; extern seqlock_t xtime_lock; static inline unsigned long get_seconds(void) -{ +{ return xtime.tv_sec; } struct timespec current_kernel_time(void); -#define CURRENT_TIME (current_kernel_time()) - -#endif /* __KERNEL__ */ - -#define NFDBITS __NFDBITS +#define CURRENT_TIME (current_kernel_time()) +#define CURRENT_TIME_SEC ((struct timespec) { xtime.tv_sec, 0 }) -#ifdef __KERNEL__ extern void do_gettimeofday(struct timeval *tv); extern int do_settimeofday(struct timespec *tv); extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz); -extern void clock_was_set(void); // call when ever the clock is set -extern int do_posix_clock_monotonic_gettime(struct timespec *tp); -extern long do_nanosleep(struct timespec *t); -extern long do_utimes(char __user * filename, struct timeval * times); +#define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts) +extern long do_utimes(int dfd, char __user *filename, struct timeval *times); struct itimerval; -extern int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue); +extern int do_setitimer(int which, struct itimerval *value, + struct itimerval *ovalue); +extern unsigned int alarm_setitimer(unsigned int seconds); extern int do_getitimer(int which, struct itimerval *value); +extern void getnstimeofday(struct timespec *tv); + +extern struct timespec timespec_trunc(struct timespec t, unsigned gran); -static inline void -set_normalized_timespec (struct timespec *ts, time_t sec, long nsec) +/** + * timespec_to_ns - Convert timespec to nanoseconds + * @ts: pointer to the timespec variable to be converted + * + * Returns the scalar nanosecond representation of the timespec + * parameter. + */ +static inline s64 timespec_to_ns(const struct timespec *ts) { - while (nsec > NSEC_PER_SEC) { - nsec -= NSEC_PER_SEC; - ++sec; - } - while (nsec < 0) { - nsec += NSEC_PER_SEC; - --sec; - } - ts->tv_sec = sec; - ts->tv_nsec = nsec; + return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec; } -#endif + +/** + * timeval_to_ns - Convert timeval to nanoseconds + * @ts: pointer to the timeval variable to be converted + * + * Returns the scalar nanosecond representation of the timeval + * parameter. + */ +static inline s64 timeval_to_ns(const struct timeval *tv) +{ + return ((s64) tv->tv_sec * NSEC_PER_SEC) + + tv->tv_usec * NSEC_PER_USEC; +} + +/** + * ns_to_timespec - Convert nanoseconds to timespec + * @nsec: the nanoseconds value to be converted + * + * Returns the timespec representation of the nsec parameter. + */ +extern struct timespec ns_to_timespec(const s64 nsec); + +/** + * ns_to_timeval - Convert nanoseconds to timeval + * @nsec: the nanoseconds value to be converted + * + * Returns the timeval representation of the nsec parameter. + */ +extern struct timeval ns_to_timeval(const s64 nsec); + +#endif /* __KERNEL__ */ + +#define NFDBITS __NFDBITS #define FD_SETSIZE __FD_SETSIZE #define FD_SET(fd,fdsetp) __FD_SET(fd,fdsetp) @@ -373,43 +154,41 @@ set_normalized_timespec (struct timespec *ts, time_t sec, long nsec) /* * Names of the interval timers, and structure - * defining a timer setting. + * defining a timer setting: */ -#define ITIMER_REAL 0 -#define ITIMER_VIRTUAL 1 -#define ITIMER_PROF 2 +#define ITIMER_REAL 0 +#define ITIMER_VIRTUAL 1 +#define ITIMER_PROF 2 -struct itimerspec { - struct timespec it_interval; /* timer period */ - struct timespec it_value; /* timer expiration */ +struct itimerspec { + struct timespec it_interval; /* timer period */ + struct timespec it_value; /* timer expiration */ }; -struct itimerval { - struct timeval it_interval; /* timer interval */ - struct timeval it_value; /* current value */ +struct itimerval { + struct timeval it_interval; /* timer interval */ + struct timeval it_value; /* current value */ }; - /* - * The IDs of the various system clocks (for POSIX.1b interval timers). + * The IDs of the various system clocks (for POSIX.1b interval timers): */ -#define CLOCK_REALTIME 0 -#define CLOCK_MONOTONIC 1 -#define CLOCK_PROCESS_CPUTIME_ID 2 -#define CLOCK_THREAD_CPUTIME_ID 3 -#define CLOCK_REALTIME_HR 4 -#define CLOCK_MONOTONIC_HR 5 - -#define MAX_CLOCKS 6 -#define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC | \ - CLOCK_REALTIME_HR | CLOCK_MONOTONIC_HR) -#define CLOCKS_MONO (CLOCK_MONOTONIC & CLOCK_MONOTONIC_HR) +#define CLOCK_REALTIME 0 +#define CLOCK_MONOTONIC 1 +#define CLOCK_PROCESS_CPUTIME_ID 2 +#define CLOCK_THREAD_CPUTIME_ID 3 /* - * The various flags for setting POSIX.1b interval timers. + * The IDs of various hardware clocks: */ +#define CLOCK_SGI_CYCLE 10 +#define MAX_CLOCKS 16 +#define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC) +#define CLOCKS_MONO CLOCK_MONOTONIC -#define TIMER_ABSTIME 0x01 - +/* + * The various flags for setting POSIX.1b interval timers: + */ +#define TIMER_ABSTIME 0x01 #endif