[PATCH] Time: Introduce arch generic time accessors (cf3c769b) · Commits · e / devices / android_kernel_xiaomi_markw

include/linux/time.h

+15 −0

Original line number	Diff line number	Diff line
		@@ -102,6 +102,7 @@ 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);
		extern int timekeeping_is_continuous(void);

		/**
		* timespec_to_ns - Convert timespec to nanoseconds
		@@ -144,6 +145,20 @@ extern struct timespec ns_to_timespec(const s64 nsec);
		*/
		extern struct timeval ns_to_timeval(const s64 nsec);

		/**
		* timespec_add_ns - Adds nanoseconds to a timespec
		* @a: pointer to timespec to be incremented
		* @ns: unsigned nanoseconds value to be added
		*/
		static inline void timespec_add_ns(struct timespec *a, u64 ns)
		{
		ns += a->tv_nsec;
		while(unlikely(ns >= NSEC_PER_SEC)) {
		ns -= NSEC_PER_SEC;
		a->tv_sec++;
		}
		a->tv_nsec = ns;
		}
		#endif /* __KERNEL__ */

		#define NFDBITS __NFDBITS

kernel/time.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -523,6 +523,7 @@ EXPORT_SYMBOL(do_gettimeofday);


		#else
		#ifndef CONFIG_GENERIC_TIME
		/*
		* Simulate gettimeofday using do_gettimeofday which only allows a timeval
		* and therefore only yields usec accuracy
		@@ -537,6 +538,7 @@ void getnstimeofday(struct timespec *tv)
		}
		EXPORT_SYMBOL_GPL(getnstimeofday);
		#endif
		#endif

		/* 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

kernel/timer.c

+170 −0

Original line number	Diff line number	Diff line
		@@ -795,6 +795,169 @@ u64 current_tick_length(long shift)
		#include <linux/clocksource.h>
		static struct clocksource clock; / pointer to current clocksource */
		static cycle_t last_clock_cycle; /* cycle value at last update_wall_time */

		#ifdef CONFIG_GENERIC_TIME
		/**
		* __get_nsec_offset - Returns nanoseconds since last call to periodic_hook
		*
		* private function, must hold xtime_lock lock when being
		* called. Returns the number of nanoseconds since the
		* last call to update_wall_time() (adjusted by NTP scaling)
		*/
		static inline s64 __get_nsec_offset(void)
		{
		cycle_t cycle_now, cycle_delta;
		s64 ns_offset;

		/* read clocksource: */
		cycle_now = read_clocksource(clock);

		/* calculate the delta since the last update_wall_time: */
		cycle_delta = (cycle_now - last_clock_cycle) & clock->mask;

		/* convert to nanoseconds: */
		ns_offset = cyc2ns(clock, cycle_delta);

		return ns_offset;
		}

		/**
		* __get_realtime_clock_ts - Returns the time of day in a timespec
		* @ts: pointer to the timespec to be set
		*
		* Returns the time of day in a timespec. Used by
		* do_gettimeofday() and get_realtime_clock_ts().
		*/
		static inline void __get_realtime_clock_ts(struct timespec *ts)
		{
		unsigned long seq;
		s64 nsecs;

		do {
		seq = read_seqbegin(&xtime_lock);

		*ts = xtime;
		nsecs = __get_nsec_offset();

		} while (read_seqretry(&xtime_lock, seq));

		timespec_add_ns(ts, nsecs);
		}

		/**
		* get_realtime_clock_ts - Returns the time of day in a timespec
		* @ts: pointer to the timespec to be set
		*
		* Returns the time of day in a timespec.
		*/
		void getnstimeofday(struct timespec *ts)
		{
		__get_realtime_clock_ts(ts);
		}

		EXPORT_SYMBOL(getnstimeofday);

		/**
		* do_gettimeofday - Returns the time of day in a timeval
		* @tv: pointer to the timeval to be set
		*
		* NOTE: Users should be converted to using get_realtime_clock_ts()
		*/
		void do_gettimeofday(struct timeval *tv)
		{
		struct timespec now;

		__get_realtime_clock_ts(&now);
		tv->tv_sec = now.tv_sec;
		tv->tv_usec = now.tv_nsec/1000;
		}

		EXPORT_SYMBOL(do_gettimeofday);
		/**
		* do_settimeofday - Sets the time of day
		* @tv: pointer to the timespec variable containing the new time
		*
		* Sets the time of day to the new time and update NTP and notify hrtimers
		*/
		int do_settimeofday(struct timespec *tv)
		{
		unsigned long flags;
		time_t wtm_sec, sec = tv->tv_sec;
		long wtm_nsec, nsec = tv->tv_nsec;

		if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
		return -EINVAL;

		write_seqlock_irqsave(&xtime_lock, flags);

		nsec -= __get_nsec_offset();

		wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
		wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);

		set_normalized_timespec(&xtime, sec, nsec);
		set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);

		ntp_clear();

		write_sequnlock_irqrestore(&xtime_lock, flags);

		/* signal hrtimers about time change */
		clock_was_set();

		return 0;
		}

		EXPORT_SYMBOL(do_settimeofday);

		/**
		* change_clocksource - Swaps clocksources if a new one is available
		*
		* Accumulates current time interval and initializes new clocksource
		*/
		static int change_clocksource(void)
		{
		struct clocksource *new;
		cycle_t now;
		u64 nsec;
		new = get_next_clocksource();
		if (clock != new) {
		now = read_clocksource(new);
		nsec = __get_nsec_offset();
		timespec_add_ns(&xtime, nsec);

		clock = new;
		last_clock_cycle = now;
		printk(KERN_INFO "Time: %s clocksource has been installed.\n",
		clock->name);
		return 1;
		} else if (clock->update_callback) {
		return clock->update_callback();
		}
		return 0;
		}
		#else
		#define change_clocksource() (0)
		#endif

		/**
		* timeofday_is_continuous - check to see if timekeeping is free running
		*/
		int timekeeping_is_continuous(void)
		{
		unsigned long seq;
		int ret;

		do {
		seq = read_seqbegin(&xtime_lock);

		ret = clock->is_continuous;

		} while (read_seqretry(&xtime_lock, seq));

		return ret;
		}

		/*
		* timekeeping_init - Initializes the clocksource and common timekeeping values
		*/
		@@ -901,6 +1064,13 @@ static void update_wall_time(void)
		/* store full nanoseconds into xtime */
		xtime.tv_nsec = remainder_snsecs >> clock->shift;
		remainder_snsecs -= (s64)xtime.tv_nsec << clock->shift;

		/* check to see if there is a new clocksource to use */
		if (change_clocksource()) {
		error = 0;
		remainder_snsecs = 0;
		calculate_clocksource_interval(clock, tick_nsec);
		}
		}

		/*