time: Rework timekeeping functions to take timekeeper ptr as argument

 *

 * Unless you're the timekeeping code, you should not be using this!

 */

static void timekeeper_setup_internals(struct clocksource *clock)

static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)

{

	cycle_t interval;

	u64 tmp, ntpinterval;

	struct clocksource *old_clock;

	old_clock = timekeeper.clock;

	timekeeper.clock = clock;

	old_clock = tk->clock;

	tk->clock = clock;

	clock->cycle_last = clock->read(clock);

	/* Do the ns -> cycle conversion first, using original mult */

		tmp = 1;

	interval = (cycle_t) tmp;

	timekeeper.cycle_interval = interval;

	tk->cycle_interval = interval;

	/* Go back from cycles -> shifted ns */

	timekeeper.xtime_interval = (u64) interval * clock->mult;

	timekeeper.xtime_remainder = ntpinterval - timekeeper.xtime_interval;

	timekeeper.raw_interval =

	tk->xtime_interval = (u64) interval * clock->mult;

	tk->xtime_remainder = ntpinterval - tk->xtime_interval;

	tk->raw_interval =

		((u64) interval * clock->mult) >> clock->shift;

	 /* if changing clocks, convert xtime_nsec shift units */

	if (old_clock) {

		int shift_change = clock->shift - old_clock->shift;

		if (shift_change < 0)

			timekeeper.xtime_nsec >>= -shift_change;

			tk->xtime_nsec >>= -shift_change;

		else

			timekeeper.xtime_nsec <<= shift_change;

			tk->xtime_nsec <<= shift_change;

	}

	timekeeper.shift = clock->shift;

	tk->shift = clock->shift;

	timekeeper.ntp_error = 0;

	timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;

	tk->ntp_error = 0;

	tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;

	/*

	 * The timekeeper keeps its own mult values for the currently

	 * active clocksource. These value will be adjusted via NTP

	 * to counteract clock drifting.

	 */

	timekeeper.mult = clock->mult;

	tk->mult = clock->mult;

}

/* Timekeeper helper functions. */

static inline s64 timekeeping_get_ns(void)

static inline s64 timekeeping_get_ns(struct timekeeper *tk)

{

	cycle_t cycle_now, cycle_delta;

	struct clocksource *clock;

	s64 nsec;

	/* read clocksource: */

	clock = timekeeper.clock;

	clock = tk->clock;

	cycle_now = clock->read(clock);

	/* calculate the delta since the last update_wall_time: */

	cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;

	nsec = cycle_delta * timekeeper.mult + timekeeper.xtime_nsec;

	nsec >>= timekeeper.shift;

	nsec = cycle_delta * tk->mult + tk->xtime_nsec;

	nsec >>= tk->shift;

	/* If arch requires, add in gettimeoffset() */

	return nsec + arch_gettimeoffset();

}

static inline s64 timekeeping_get_ns_raw(void)

static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk)

{

	cycle_t cycle_now, cycle_delta;

	struct clocksource *clock;

	s64 nsec;

	/* read clocksource: */

	clock = timekeeper.clock;

	clock = tk->clock;

	cycle_now = clock->read(clock);

	/* calculate the delta since the last update_wall_time: */

	return nsec + arch_gettimeoffset();

}

static void update_rt_offset(void)

static void update_rt_offset(struct timekeeper *tk)

{

	struct timespec tmp, *wtm = &timekeeper.wall_to_monotonic;

	struct timespec tmp, *wtm = &tk->wall_to_monotonic;

	set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec);

	timekeeper.offs_real = timespec_to_ktime(tmp);

	tk->offs_real = timespec_to_ktime(tmp);

}

/* must hold write on timekeeper.lock */

static void timekeeping_update(bool clearntp)

static void timekeeping_update(struct timekeeper *tk, bool clearntp)

{

	struct timespec xt;

	if (clearntp) {

		timekeeper.ntp_error = 0;

		tk->ntp_error = 0;

		ntp_clear();

	}

	update_rt_offset();

	xt = tk_xtime(&timekeeper);

	update_vsyscall(&xt, &timekeeper.wall_to_monotonic,

			 timekeeper.clock, timekeeper.mult);

	update_rt_offset(tk);

	xt = tk_xtime(tk);

	update_vsyscall(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult);

}

 * update_wall_time(). This is useful before significant clock changes,

 * as it avoids having to deal with this time offset explicitly.

 */

static void timekeeping_forward_now(void)

static void timekeeping_forward_now(struct timekeeper *tk)

{

	cycle_t cycle_now, cycle_delta;

	struct clocksource *clock;

	s64 nsec;

	clock = timekeeper.clock;

	clock = tk->clock;

	cycle_now = clock->read(clock);

	cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;

	clock->cycle_last = cycle_now;

	timekeeper.xtime_nsec += cycle_delta * timekeeper.mult;

	tk->xtime_nsec += cycle_delta * tk->mult;

	/* If arch requires, add in gettimeoffset() */

	timekeeper.xtime_nsec += arch_gettimeoffset() << timekeeper.shift;

	tk->xtime_nsec += arch_gettimeoffset() << tk->shift;

	tk_normalize_xtime(&timekeeper);

	tk_normalize_xtime(tk);

	nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);

	timespec_add_ns(&timekeeper.raw_time, nsec);

	timespec_add_ns(&tk->raw_time, nsec);

}

/**

		seq = read_seqbegin(&timekeeper.lock);

		ts->tv_sec = timekeeper.xtime_sec;

		ts->tv_nsec = timekeeping_get_ns();

		ts->tv_nsec = timekeeping_get_ns(&timekeeper);

	} while (read_seqretry(&timekeeper.lock, seq));

		seq = read_seqbegin(&timekeeper.lock);

		secs = timekeeper.xtime_sec +

				timekeeper.wall_to_monotonic.tv_sec;

		nsecs = timekeeping_get_ns() +

		nsecs = timekeeping_get_ns(&timekeeper) +

				timekeeper.wall_to_monotonic.tv_nsec;

	} while (read_seqretry(&timekeeper.lock, seq));

	do {

		seq = read_seqbegin(&timekeeper.lock);

		ts->tv_sec = timekeeper.xtime_sec;

		ts->tv_nsec = timekeeping_get_ns();

		ts->tv_nsec = timekeeping_get_ns(&timekeeper);

		tomono = timekeeper.wall_to_monotonic;

	} while (read_seqretry(&timekeeper.lock, seq));

		ts_real->tv_sec = timekeeper.xtime_sec;

		ts_real->tv_nsec = 0;

		nsecs_raw = timekeeping_get_ns_raw();

		nsecs_real = timekeeping_get_ns();

		nsecs_raw = timekeeping_get_ns_raw(&timekeeper);

		nsecs_real = timekeeping_get_ns(&timekeeper);

	} while (read_seqretry(&timekeeper.lock, seq));

	write_seqlock_irqsave(&timekeeper.lock, flags);

	timekeeping_forward_now();

	timekeeping_forward_now(&timekeeper);

	xt = tk_xtime(&timekeeper);

	ts_delta.tv_sec = tv->tv_sec - xt.tv_sec;

	tk_set_xtime(&timekeeper, tv);

	timekeeping_update(true);

	timekeeping_update(&timekeeper, true);

	write_sequnlock_irqrestore(&timekeeper.lock, flags);

	write_seqlock_irqsave(&timekeeper.lock, flags);

	timekeeping_forward_now();

	timekeeping_forward_now(&timekeeper);

	tk_xtime_add(&timekeeper, ts);

	timekeeper.wall_to_monotonic =

				timespec_sub(timekeeper.wall_to_monotonic, *ts);

	timekeeping_update(true);

	timekeeping_update(&timekeeper, true);

	write_sequnlock_irqrestore(&timekeeper.lock, flags);

	write_seqlock_irqsave(&timekeeper.lock, flags);

	timekeeping_forward_now();

	timekeeping_forward_now(&timekeeper);

	if (!new->enable || new->enable(new) == 0) {

		old = timekeeper.clock;

		timekeeper_setup_internals(new);

		tk_setup_internals(&timekeeper, new);

		if (old->disable)

			old->disable(old);

	}

	timekeeping_update(true);

	timekeeping_update(&timekeeper, true);

	write_sequnlock_irqrestore(&timekeeper.lock, flags);

	do {

		seq = read_seqbegin(&timekeeper.lock);

		nsecs = timekeeping_get_ns_raw();

		nsecs = timekeeping_get_ns_raw(&timekeeper);

		*ts = timekeeper.raw_time;

	} while (read_seqretry(&timekeeper.lock, seq));

	clock = clocksource_default_clock();

	if (clock->enable)

		clock->enable(clock);

	timekeeper_setup_internals(clock);

	tk_setup_internals(&timekeeper, clock);

	tk_set_xtime(&timekeeper, &now);

	timekeeper.raw_time.tv_sec = 0;

	set_normalized_timespec(&timekeeper.wall_to_monotonic,

				-boot.tv_sec, -boot.tv_nsec);

	update_rt_offset();

	update_rt_offset(&timekeeper);

	timekeeper.total_sleep_time.tv_sec = 0;

	timekeeper.total_sleep_time.tv_nsec = 0;

	write_sequnlock_irqrestore(&timekeeper.lock, flags);

 * Takes a timespec offset measuring a suspend interval and properly

 * adds the sleep offset to the timekeeping variables.

 */

static void __timekeeping_inject_sleeptime(struct timespec *delta)

static void __timekeeping_inject_sleeptime(struct timekeeper *tk,

							struct timespec *delta)

{

	if (!timespec_valid(delta)) {

		printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid "

		return;

	}

	tk_xtime_add(&timekeeper, delta);

	timekeeper.wall_to_monotonic =

			timespec_sub(timekeeper.wall_to_monotonic, *delta);

	update_sleep_time(timespec_add(timekeeper.total_sleep_time, *delta));

	tk_xtime_add(tk, delta);

	tk->wall_to_monotonic = timespec_sub(tk->wall_to_monotonic, *delta);

	update_sleep_time(timespec_add(tk->total_sleep_time, *delta));

}

	write_seqlock_irqsave(&timekeeper.lock, flags);

	timekeeping_forward_now();

	timekeeping_forward_now(&timekeeper);

	__timekeeping_inject_sleeptime(delta);

	__timekeeping_inject_sleeptime(&timekeeper, delta);

	timekeeping_update(true);

	timekeeping_update(&timekeeper, true);

	write_sequnlock_irqrestore(&timekeeper.lock, flags);

	if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {

		ts = timespec_sub(ts, timekeeping_suspend_time);

		__timekeeping_inject_sleeptime(&ts);

		__timekeeping_inject_sleeptime(&timekeeper, &ts);

	}

	/* re-base the last cycle value */

	timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);

	read_persistent_clock(&timekeeping_suspend_time);

	write_seqlock_irqsave(&timekeeper.lock, flags);

	timekeeping_forward_now();

	timekeeping_forward_now(&timekeeper);

	timekeeping_suspended = 1;

	/*

 * If the error is already larger, we look ahead even further

 * to compensate for late or lost adjustments.

 */

static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,

static __always_inline int timekeeping_bigadjust(struct timekeeper *tk,

						 s64 error, s64 *interval,

						 s64 *offset)

{

	s64 tick_error, i;

	 * here.  This is tuned so that an error of about 1 msec is adjusted

	 * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks).

	 */

	error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);

	error2 = tk->ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);

	error2 = abs(error2);

	for (look_ahead = 0; error2 > 0; look_ahead++)

		error2 >>= 2;

	 * Now calculate the error in (1 << look_ahead) ticks, but first

	 * remove the single look ahead already included in the error.

	 */

	tick_error = ntp_tick_length() >> (timekeeper.ntp_error_shift + 1);

	tick_error -= timekeeper.xtime_interval >> 1;

	tick_error = ntp_tick_length() >> (tk->ntp_error_shift + 1);

	tick_error -= tk->xtime_interval >> 1;

	error = ((error - tick_error) >> look_ahead) + tick_error;

	/* Finally calculate the adjustment shift value.  */

 * this is optimized for the most common adjustments of -1,0,1,

 * for other values we can do a bit more work.

 */

static void timekeeping_adjust(s64 offset)

static void timekeeping_adjust(struct timekeeper *tk, s64 offset)

{

	s64 error, interval = timekeeper.cycle_interval;

	s64 error, interval = tk->cycle_interval;

	int adj;

	/*

	 *

	 * Note: It does not "save" on aggravation when reading the code.

	 */

	error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1);

	error = tk->ntp_error >> (tk->ntp_error_shift - 1);

	if (error > interval) {

		/*

		 * We now divide error by 4(via shift), which checks if

		if (likely(error <= interval))

			adj = 1;

		else

			adj = timekeeping_bigadjust(error, &interval, &offset);

			adj = timekeeping_bigadjust(tk, error, &interval,

							&offset);

	} else if (error < -interval) {

		/* See comment above, this is just switched for the negative */

		error >>= 2;

			interval = -interval;

			offset = -offset;

		} else

			adj = timekeeping_bigadjust(error, &interval, &offset);

	} else /* No adjustment needed */

			adj = timekeeping_bigadjust(tk, error, &interval,

							&offset);

	} else

		return;

	if (unlikely(timekeeper.clock->maxadj &&

			(timekeeper.mult + adj >

			timekeeper.clock->mult + timekeeper.clock->maxadj))) {

	if (unlikely(tk->clock->maxadj &&

		(tk->mult + adj > tk->clock->mult + tk->clock->maxadj))) {

		printk_once(KERN_WARNING

			"Adjusting %s more than 11%% (%ld vs %ld)\n",

			timekeeper.clock->name, (long)timekeeper.mult + adj,

			(long)timekeeper.clock->mult +

				timekeeper.clock->maxadj);

			tk->clock->name, (long)tk->mult + adj,

			(long)tk->clock->mult + tk->clock->maxadj);

	}

	/*

	 * So the following can be confusing.

	 *

	 * XXX - TODO: Doc ntp_error calculation.

	 */

	timekeeper.mult += adj;

	timekeeper.xtime_interval += interval;

	timekeeper.xtime_nsec -= offset;

	timekeeper.ntp_error -= (interval - offset) <<

				timekeeper.ntp_error_shift;

	tk->mult += adj;

	tk->xtime_interval += interval;

	tk->xtime_nsec -= offset;

	tk->ntp_error -= (interval - offset) << tk->ntp_error_shift;

	/*

	 * It may be possible that when we entered this function, xtime_nsec

	 * We'll correct this error next time through this function, when

	 * xtime_nsec is not as small.

	 */

	if (unlikely((s64)timekeeper.xtime_nsec < 0)) {

		s64 neg = -(s64)timekeeper.xtime_nsec;

		timekeeper.xtime_nsec = 0;

		timekeeper.ntp_error += neg << timekeeper.ntp_error_shift;

	if (unlikely((s64)tk->xtime_nsec < 0)) {

		s64 neg = -(s64)tk->xtime_nsec;

		tk->xtime_nsec = 0;

		tk->ntp_error += neg << tk->ntp_error_shift;

	}

}

 *

 * Returns the unconsumed cycles.

 */

static cycle_t logarithmic_accumulation(cycle_t offset, u32 shift)

static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,

						u32 shift)

{

	u64 raw_nsecs;

	/* If the offset is smaller than a shifted interval, do nothing */

	if (offset < timekeeper.cycle_interval<<shift)

	/* If the offset is smaller then a shifted interval, do nothing */

	if (offset < tk->cycle_interval<<shift)

		return offset;

	/* Accumulate one shifted interval */

	offset -= timekeeper.cycle_interval << shift;

	timekeeper.clock->cycle_last += timekeeper.cycle_interval << shift;

	offset -= tk->cycle_interval << shift;

	tk->clock->cycle_last += tk->cycle_interval << shift;

	timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;

	accumulate_nsecs_to_secs(&timekeeper);

	tk->xtime_nsec += tk->xtime_interval << shift;

	accumulate_nsecs_to_secs(tk);

	/* Accumulate raw time */

	raw_nsecs = timekeeper.raw_interval << shift;

	raw_nsecs += timekeeper.raw_time.tv_nsec;

	raw_nsecs = tk->raw_interval << shift;

	raw_nsecs += tk->raw_time.tv_nsec;

	if (raw_nsecs >= NSEC_PER_SEC) {

		u64 raw_secs = raw_nsecs;

		raw_nsecs = do_div(raw_secs, NSEC_PER_SEC);

		timekeeper.raw_time.tv_sec += raw_secs;

		tk->raw_time.tv_sec += raw_secs;

	}

	timekeeper.raw_time.tv_nsec = raw_nsecs;

	tk->raw_time.tv_nsec = raw_nsecs;

	/* Accumulate error between NTP and clock interval */

	timekeeper.ntp_error += ntp_tick_length() << shift;

	timekeeper.ntp_error -=

	    (timekeeper.xtime_interval + timekeeper.xtime_remainder) <<

				(timekeeper.ntp_error_shift + shift);

	tk->ntp_error += ntp_tick_length() << shift;

	tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) <<

						(tk->ntp_error_shift + shift);

	return offset;

}

	maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;

	shift = min(shift, maxshift);

	while (offset >= timekeeper.cycle_interval) {

		offset = logarithmic_accumulation(offset, shift);

		offset = logarithmic_accumulation(&timekeeper, offset, shift);

		if(offset < timekeeper.cycle_interval<<shift)

			shift--;

	}

	/* correct the clock when NTP error is too big */

	timekeeping_adjust(offset);

	timekeeping_adjust(&timekeeper, offset);

	/*

	 */

	accumulate_nsecs_to_secs(&timekeeper);

	timekeeping_update(false);

	timekeeping_update(&timekeeper, false);

out:

	write_sequnlock_irqrestore(&timekeeper.lock, flags);

	do {

		seq = read_seqbegin(&timekeeper.lock);

		ts->tv_sec = timekeeper.xtime_sec;

		ts->tv_nsec = timekeeping_get_ns();

		ts->tv_nsec = timekeeping_get_ns(&timekeeper);

		tomono = timekeeper.wall_to_monotonic;

		sleep = timekeeper.total_sleep_time;

		seq = read_seqbegin(&timekeeper.lock);

		secs = timekeeper.xtime_sec;

		nsecs = timekeeping_get_ns();

		nsecs = timekeeping_get_ns(&timekeeper);

		*offs_real = timekeeper.offs_real;

		*offs_boot = timekeeper.offs_boot;