#ifdef CONFIG_GENERIC_TIME
/**
- * __get_nsec_offset - Returns nanoseconds since last call to periodic_hook
+ * clocksource_forward_now - update clock to the current time
*
- * 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)
+ * Forward the current clock to update its state since the last call to
+ * update_wall_time(). This is useful before significant clock changes,
+ * as it avoids having to deal with this time offset explicitly.
*/
-static inline s64 __get_nsec_offset(void)
+static void clocksource_forward_now(void)
{
cycle_t cycle_now, cycle_delta;
- s64 ns_offset;
+ s64 nsec;
- /* read clocksource: */
cycle_now = clocksource_read(clock);
-
- /* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
+ clock->cycle_last = cycle_now;
- /* convert to nanoseconds: */
- ns_offset = cyc2ns(clock, cycle_delta);
+ nsec = cyc2ns(clock, cycle_delta);
+ timespec_add_ns(&xtime, nsec);
- return ns_offset;
+ nsec = ((s64)cycle_delta * clock->mult_orig) >> clock->shift;
+ clock->raw_time.tv_nsec += nsec;
}
/**
*/
void getnstimeofday(struct timespec *ts)
{
+ cycle_t cycle_now, cycle_delta;
unsigned long seq;
s64 nsecs;
seq = read_seqbegin(&xtime_lock);
*ts = xtime;
- nsecs = __get_nsec_offset();
+
+ /* read clocksource: */
+ cycle_now = clocksource_read(clock);
+
+ /* calculate the delta since the last update_wall_time: */
+ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
+
+ /* convert to nanoseconds: */
+ nsecs = cyc2ns(clock, cycle_delta);
} while (read_seqretry(&xtime_lock, seq));
*/
int do_settimeofday(struct timespec *tv)
{
+ struct timespec ts_delta;
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();
+ clocksource_forward_now();
+
+ ts_delta.tv_sec = tv->tv_sec - xtime.tv_sec;
+ ts_delta.tv_nsec = tv->tv_nsec - xtime.tv_nsec;
+ wall_to_monotonic = timespec_sub(wall_to_monotonic, ts_delta);
- wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
- wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
+ xtime = *tv;
- set_normalized_timespec(&xtime, sec, nsec);
- set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
update_xtime_cache(0);
clock->error = 0;
static void change_clocksource(void)
{
struct clocksource *new;
- cycle_t now;
- u64 nsec;
new = clocksource_get_next();
if (clock == new)
return;
- new->cycle_last = 0;
- now = clocksource_read(new);
- nsec = __get_nsec_offset();
- timespec_add_ns(&xtime, nsec);
+ clocksource_forward_now();
- clock = new;
- clock->cycle_last = now;
+ new->raw_time = clock->raw_time;
+ clock = new;
+ clock->cycle_last = 0;
+ clock->cycle_last = clocksource_read(new);
clock->error = 0;
clock->xtime_nsec = 0;
clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
*/
}
#else
+static inline void clocksource_forward_now(void) { }
static inline void change_clocksource(void) { }
-static inline s64 __get_nsec_offset(void) { return 0; }
#endif
+/**
+ * getrawmonotonic - Returns the raw monotonic time in a timespec
+ * @ts: pointer to the timespec to be set
+ *
+ * Returns the raw monotonic time (completely un-modified by ntp)
+ */
+void getrawmonotonic(struct timespec *ts)
+{
+ unsigned long seq;
+ s64 nsecs;
+ cycle_t cycle_now, cycle_delta;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+
+ /* read clocksource: */
+ cycle_now = clocksource_read(clock);
+
+ /* calculate the delta since the last update_wall_time: */
+ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
+
+ /* convert to nanoseconds: */
+ nsecs = ((s64)cycle_delta * clock->mult_orig) >> clock->shift;
+
+ *ts = clock->raw_time;
+
+ } while (read_seqretry(&xtime_lock, seq));
+
+ timespec_add_ns(ts, nsecs);
+}
+EXPORT_SYMBOL(getrawmonotonic);
+
+
/**
* timekeeping_valid_for_hres - Check if timekeeping is suitable for hres
*/
static int timekeeping_suspended;
/* time in seconds when suspend began */
static unsigned long timekeeping_suspend_time;
-/* xtime offset when we went into suspend */
-static s64 timekeeping_suspend_nsecs;
/**
* timekeeping_resume - Resumes the generic timekeeping subsystem.
wall_to_monotonic.tv_sec -= sleep_length;
total_sleep_time += sleep_length;
}
- /* Make sure that we have the correct xtime reference */
- timespec_add_ns(&xtime, timekeeping_suspend_nsecs);
update_xtime_cache(0);
/* re-base the last cycle value */
clock->cycle_last = 0;
timekeeping_suspend_time = read_persistent_clock();
write_seqlock_irqsave(&xtime_lock, flags);
- /* Get the current xtime offset */
- timekeeping_suspend_nsecs = __get_nsec_offset();
+ clocksource_forward_now();
timekeeping_suspended = 1;
write_sequnlock_irqrestore(&xtime_lock, flags);
#else
offset = clock->cycle_interval;
#endif
- clock->xtime_nsec += (s64)xtime.tv_nsec << clock->shift;
+ clock->xtime_nsec = (s64)xtime.tv_nsec << clock->shift;
/* normally this loop will run just once, however in the
* case of lost or late ticks, it will accumulate correctly.
*/
while (offset >= clock->cycle_interval) {
/* accumulate one interval */
- clock->xtime_nsec += clock->xtime_interval;
- clock->cycle_last += clock->cycle_interval;
offset -= clock->cycle_interval;
+ clock->cycle_last += clock->cycle_interval;
+ clock->xtime_nsec += clock->xtime_interval;
if (clock->xtime_nsec >= (u64)NSEC_PER_SEC << clock->shift) {
clock->xtime_nsec -= (u64)NSEC_PER_SEC << clock->shift;
xtime.tv_sec++;
second_overflow();
}
+ clock->raw_time.tv_nsec += clock->raw_interval;
+ if (clock->raw_time.tv_nsec >= NSEC_PER_SEC) {
+ clock->raw_time.tv_nsec -= NSEC_PER_SEC;
+ clock->raw_time.tv_sec++;
+ }
+
/* accumulate error between NTP and clock interval */
clock->error += tick_length;
clock->error -= clock->xtime_interval << (NTP_SCALE_SHIFT - clock->shift);
/* correct the clock when NTP error is too big */
clocksource_adjust(offset);
- /* store full nanoseconds into xtime */
- xtime.tv_nsec = (s64)clock->xtime_nsec >> clock->shift;
+ /* store full nanoseconds into xtime after rounding it up and
+ * add the remainder to the error difference.
+ */
+ xtime.tv_nsec = ((s64)clock->xtime_nsec >> clock->shift) + 1;
clock->xtime_nsec -= (s64)xtime.tv_nsec << clock->shift;
+ clock->error += clock->xtime_nsec << (NTP_SCALE_SHIFT - clock->shift);
update_xtime_cache(cyc2ns(clock, offset));
Code Review / linux-2.6.git / blobdiff