From 49cd6f869984692547c57621bf42697aaa7f5622 Mon Sep 17 00:00:00 2001 From: John Stultz Date: Wed, 16 Jul 2014 21:03:59 +0000 Subject: [PATCH] time: More core infrastructure for timespec64 Helper and conversion functions for timespec64. Signed-off-by: John Stultz Signed-off-by: Thomas Gleixner Signed-off-by: John Stultz --- include/linux/ktime.h | 28 +++++++++++++++++++ include/linux/time64.h | 28 +++++++++++++++++++ kernel/time/time.c | 62 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 118 insertions(+) diff --git a/include/linux/ktime.h b/include/linux/ktime.h index 538c283714e1..da6b680c252b 100644 --- a/include/linux/ktime.h +++ b/include/linux/ktime.h @@ -83,6 +83,12 @@ 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) { @@ -92,6 +98,9 @@ static inline ktime_t timeval_to_ktime(struct timeval tv) /* 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) @@ -213,6 +222,25 @@ static inline __must_check bool ktime_to_timespec_cond(const ktime_t kt, } } +/** + * 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 diff --git a/include/linux/time64.h b/include/linux/time64.h index e7b499e1cd79..a3831478d9cf 100644 --- a/include/linux/time64.h +++ b/include/linux/time64.h @@ -33,6 +33,16 @@ struct timespec64 { #if __BITS_PER_LONG == 64 +static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64) +{ + return ts64; +} + +static inline struct timespec64 timespec_to_timespec64(const struct timespec ts) +{ + return ts; +} + # define timespec64_equal timespec_equal # define timespec64_compare timespec_compare # define set_normalized_timespec64 set_normalized_timespec @@ -47,6 +57,24 @@ struct timespec64 { #else +static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64) +{ + struct timespec ret; + + ret.tv_sec = (time_t)ts64.tv_sec; + ret.tv_nsec = ts64.tv_nsec; + return ret; +} + +static inline struct timespec64 timespec_to_timespec64(const struct timespec ts) +{ + struct timespec64 ret; + + ret.tv_sec = ts.tv_sec; + ret.tv_nsec = ts.tv_nsec; + return ret; +} + static inline int timespec64_equal(const struct timespec64 *a, const struct timespec64 *b) { diff --git a/kernel/time/time.c b/kernel/time/time.c index 7c7964c33ae7..e8121a67fd74 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -420,6 +420,68 @@ struct timeval ns_to_timeval(const s64 nsec) } EXPORT_SYMBOL(ns_to_timeval); +#if BITS_PER_LONG == 32 +/** + * set_normalized_timespec - set timespec sec and nsec parts and normalize + * + * @ts: pointer to timespec variable to be set + * @sec: seconds to set + * @nsec: nanoseconds to set + * + * Set seconds and nanoseconds field of a timespec variable and + * normalize to the timespec storage format + * + * Note: The tv_nsec part is always in the range of + * 0 <= tv_nsec < NSEC_PER_SEC + * For negative values only the tv_sec field is negative ! + */ +void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec) +{ + while (nsec >= NSEC_PER_SEC) { + /* + * The following asm() prevents the compiler from + * optimising this loop into a modulo operation. See + * also __iter_div_u64_rem() in include/linux/time.h + */ + asm("" : "+rm"(nsec)); + nsec -= NSEC_PER_SEC; + ++sec; + } + while (nsec < 0) { + asm("" : "+rm"(nsec)); + nsec += NSEC_PER_SEC; + --sec; + } + ts->tv_sec = sec; + ts->tv_nsec = nsec; +} +EXPORT_SYMBOL(set_normalized_timespec64); + +/** + * ns_to_timespec64 - Convert nanoseconds to timespec64 + * @nsec: the nanoseconds value to be converted + * + * Returns the timespec64 representation of the nsec parameter. + */ +struct timespec64 ns_to_timespec64(const s64 nsec) +{ + struct timespec64 ts; + s32 rem; + + if (!nsec) + return (struct timespec64) {0, 0}; + + ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem); + if (unlikely(rem < 0)) { + ts.tv_sec--; + rem += NSEC_PER_SEC; + } + ts.tv_nsec = rem; + + return ts; +} +EXPORT_SYMBOL(ns_to_timespec64); +#endif /* * When we convert to jiffies then we interpret incoming values * the following way: -- 2.20.1