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author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /include/linux/ktime.h |
Initial import
Diffstat (limited to 'include/linux/ktime.h')
-rw-r--r-- | include/linux/ktime.h | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/include/linux/ktime.h b/include/linux/ktime.h new file mode 100644 index 000000000..2b6a204bd --- /dev/null +++ b/include/linux/ktime.h @@ -0,0 +1,299 @@ +/* + * include/linux/ktime.h + * + * ktime_t - nanosecond-resolution time format. + * + * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de> + * Copyright(C) 2005, Red Hat, Inc., Ingo Molnar + * + * data type definitions, declarations, prototypes and macros. + * + * Started by: Thomas Gleixner and Ingo Molnar + * + * Credits: + * + * Roman Zippel provided the ideas and primary code snippets of + * the ktime_t union and further simplifications of the original + * code. + * + * For licencing details see kernel-base/COPYING + */ +#ifndef _LINUX_KTIME_H +#define _LINUX_KTIME_H + +#include <linux/time.h> +#include <linux/jiffies.h> + +/* + * ktime_t: + * + * A single 64-bit variable is used to store the hrtimers + * internal representation of time values in scalar nanoseconds. The + * design plays out best on 64-bit CPUs, where most conversions are + * NOPs and most arithmetic ktime_t operations are plain arithmetic + * operations. + * + */ +union ktime { + s64 tv64; +}; + +typedef union ktime ktime_t; /* Kill this */ + +/** + * ktime_set - Set a ktime_t variable from a seconds/nanoseconds value + * @secs: seconds to set + * @nsecs: nanoseconds to set + * + * Return: The ktime_t representation of the value. + */ +static inline ktime_t ktime_set(const s64 secs, const unsigned long nsecs) +{ + if (unlikely(secs >= KTIME_SEC_MAX)) + return (ktime_t){ .tv64 = KTIME_MAX }; + + return (ktime_t) { .tv64 = secs * NSEC_PER_SEC + (s64)nsecs }; +} + +/* Subtract two ktime_t variables. rem = lhs -rhs: */ +#define ktime_sub(lhs, rhs) \ + ({ (ktime_t){ .tv64 = (lhs).tv64 - (rhs).tv64 }; }) + +/* Add two ktime_t variables. res = lhs + rhs: */ +#define ktime_add(lhs, rhs) \ + ({ (ktime_t){ .tv64 = (lhs).tv64 + (rhs).tv64 }; }) + +/* + * Add a ktime_t variable and a scalar nanosecond value. + * res = kt + nsval: + */ +#define ktime_add_ns(kt, nsval) \ + ({ (ktime_t){ .tv64 = (kt).tv64 + (nsval) }; }) + +/* + * Subtract a scalar nanosecod from a ktime_t variable + * res = kt - nsval: + */ +#define ktime_sub_ns(kt, nsval) \ + ({ (ktime_t){ .tv64 = (kt).tv64 - (nsval) }; }) + +/* convert a timespec to ktime_t format: */ +static inline ktime_t timespec_to_ktime(struct timespec ts) +{ + return ktime_set(ts.tv_sec, ts.tv_nsec); +} + +/* convert a timespec64 to ktime_t format: */ +static inline ktime_t timespec64_to_ktime(struct timespec64 ts) +{ + return ktime_set(ts.tv_sec, ts.tv_nsec); +} + +/* convert a timeval to ktime_t format: */ +static inline ktime_t timeval_to_ktime(struct timeval tv) +{ + return ktime_set(tv.tv_sec, tv.tv_usec * NSEC_PER_USEC); +} + +/* Map the ktime_t to timespec conversion to ns_to_timespec function */ +#define ktime_to_timespec(kt) ns_to_timespec((kt).tv64) + +/* Map the ktime_t to timespec conversion to ns_to_timespec function */ +#define ktime_to_timespec64(kt) ns_to_timespec64((kt).tv64) + +/* Map the ktime_t to timeval conversion to ns_to_timeval function */ +#define ktime_to_timeval(kt) ns_to_timeval((kt).tv64) + +/* Convert ktime_t to nanoseconds - NOP in the scalar storage format: */ +#define ktime_to_ns(kt) ((kt).tv64) + + +/** + * ktime_equal - Compares two ktime_t variables to see if they are equal + * @cmp1: comparable1 + * @cmp2: comparable2 + * + * Compare two ktime_t variables. + * + * Return: 1 if equal. + */ +static inline int ktime_equal(const ktime_t cmp1, const ktime_t cmp2) +{ + return cmp1.tv64 == cmp2.tv64; +} + +/** + * ktime_compare - Compares two ktime_t variables for less, greater or equal + * @cmp1: comparable1 + * @cmp2: comparable2 + * + * Return: ... + * cmp1 < cmp2: return <0 + * cmp1 == cmp2: return 0 + * cmp1 > cmp2: return >0 + */ +static inline int ktime_compare(const ktime_t cmp1, const ktime_t cmp2) +{ + if (cmp1.tv64 < cmp2.tv64) + return -1; + if (cmp1.tv64 > cmp2.tv64) + return 1; + return 0; +} + +/** + * ktime_after - Compare if a ktime_t value is bigger than another one. + * @cmp1: comparable1 + * @cmp2: comparable2 + * + * Return: true if cmp1 happened after cmp2. + */ +static inline bool ktime_after(const ktime_t cmp1, const ktime_t cmp2) +{ + return ktime_compare(cmp1, cmp2) > 0; +} + +/** + * ktime_before - Compare if a ktime_t value is smaller than another one. + * @cmp1: comparable1 + * @cmp2: comparable2 + * + * Return: true if cmp1 happened before cmp2. + */ +static inline bool ktime_before(const ktime_t cmp1, const ktime_t cmp2) +{ + return ktime_compare(cmp1, cmp2) < 0; +} + +#if BITS_PER_LONG < 64 +extern s64 __ktime_divns(const ktime_t kt, s64 div); +static inline s64 ktime_divns(const ktime_t kt, s64 div) +{ + /* + * Negative divisors could cause an inf loop, + * so bug out here. + */ + BUG_ON(div < 0); + if (__builtin_constant_p(div) && !(div >> 32)) { + s64 ns = kt.tv64; + u64 tmp = ns < 0 ? -ns : ns; + + do_div(tmp, div); + return ns < 0 ? -tmp : tmp; + } else { + return __ktime_divns(kt, div); + } +} +#else /* BITS_PER_LONG < 64 */ +static inline s64 ktime_divns(const ktime_t kt, s64 div) +{ + /* + * 32-bit implementation cannot handle negative divisors, + * so catch them on 64bit as well. + */ + WARN_ON(div < 0); + return kt.tv64 / div; +} +#endif + +static inline s64 ktime_to_us(const ktime_t kt) +{ + return ktime_divns(kt, NSEC_PER_USEC); +} + +static inline s64 ktime_to_ms(const ktime_t kt) +{ + return ktime_divns(kt, NSEC_PER_MSEC); +} + +static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier) +{ + return ktime_to_us(ktime_sub(later, earlier)); +} + +static inline s64 ktime_ms_delta(const ktime_t later, const ktime_t earlier) +{ + return ktime_to_ms(ktime_sub(later, earlier)); +} + +static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec) +{ + return ktime_add_ns(kt, usec * NSEC_PER_USEC); +} + +static inline ktime_t ktime_add_ms(const ktime_t kt, const u64 msec) +{ + return ktime_add_ns(kt, msec * NSEC_PER_MSEC); +} + +static inline ktime_t ktime_sub_us(const ktime_t kt, const u64 usec) +{ + return ktime_sub_ns(kt, usec * NSEC_PER_USEC); +} + +extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs); + +/** + * ktime_to_timespec_cond - convert a ktime_t variable to timespec + * format only if the variable contains data + * @kt: the ktime_t variable to convert + * @ts: the timespec variable to store the result in + * + * Return: %true if there was a successful conversion, %false if kt was 0. + */ +static inline __must_check bool ktime_to_timespec_cond(const ktime_t kt, + struct timespec *ts) +{ + if (kt.tv64) { + *ts = ktime_to_timespec(kt); + return true; + } else { + return false; + } +} + +/** + * ktime_to_timespec64_cond - convert a ktime_t variable to timespec64 + * format only if the variable contains data + * @kt: the ktime_t variable to convert + * @ts: the timespec variable to store the result in + * + * Return: %true if there was a successful conversion, %false if kt was 0. + */ +static inline __must_check bool ktime_to_timespec64_cond(const ktime_t kt, + struct timespec64 *ts) +{ + if (kt.tv64) { + *ts = ktime_to_timespec64(kt); + return true; + } else { + return false; + } +} + +/* + * The resolution of the clocks. The resolution value is returned in + * the clock_getres() system call to give application programmers an + * idea of the (in)accuracy of timers. Timer values are rounded up to + * this resolution values. + */ +#define LOW_RES_NSEC TICK_NSEC +#define KTIME_LOW_RES (ktime_t){ .tv64 = LOW_RES_NSEC } + +static inline ktime_t ns_to_ktime(u64 ns) +{ + static const ktime_t ktime_zero = { .tv64 = 0 }; + + return ktime_add_ns(ktime_zero, ns); +} + +static inline ktime_t ms_to_ktime(u64 ms) +{ + static const ktime_t ktime_zero = { .tv64 = 0 }; + + return ktime_add_ms(ktime_zero, ms); +} + +# include <linux/timekeeping.h> + +#endif |