diff options
| -rw-r--r-- | include/linux/timex.h | 1 | ||||
| -rw-r--r-- | kernel/time/ntp.c | 71 | ||||
| -rw-r--r-- | kernel/timer.c | 2 |
3 files changed, 18 insertions, 56 deletions
diff --git a/include/linux/timex.h b/include/linux/timex.h index 1cde6f6a271..b5f297e1766 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -217,7 +217,6 @@ extern long time_freq; /* frequency offset (scaled ppm) */ extern long time_reftime; /* time at last adjustment (s) */ extern long time_adjust; /* The amount of adjtime left */ -extern long time_next_adjust; /* Value for time_adjust at next tick */ extern void ntp_clear(void); extern void ntp_update_frequency(void); diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 238ce47ef09..65223b7ed81 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -22,8 +22,9 @@ unsigned long tick_usec = TICK_USEC; /* USER_HZ period (usec) */ unsigned long tick_nsec; /* ACTHZ period (nsec) */ static u64 tick_length, tick_length_base; -/* Don't completely fail for HZ > 500. */ -int tickadj = 500/HZ ? : 1; /* microsecs */ +#define MAX_TICKADJ 500 /* microsecs */ +#define MAX_TICKADJ_SCALED (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << \ + TICK_LENGTH_SHIFT) / HZ) /* * phase-lock loop variables @@ -40,7 +41,6 @@ long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */ long time_freq; /* frequency offset (scaled ppm)*/ long time_reftime; /* time at last adjustment (s) */ long time_adjust; -long time_next_adjust; /** * ntp_clear - Clears the NTP state variables @@ -160,46 +160,19 @@ void second_overflow(void) time_adj = max(time_adj, ((MAXPHASE / HZ) << SHIFT_UPDATE) / MINSEC); time_offset -= time_adj; tick_length += (s64)time_adj << (TICK_LENGTH_SHIFT - SHIFT_UPDATE); -} - -/* - * Returns how many microseconds we need to add to xtime this tick - * in doing an adjustment requested with adjtime. - */ -static long adjtime_adjustment(void) -{ - long time_adjust_step; - - time_adjust_step = time_adjust; - if (time_adjust_step) { - /* - * We are doing an adjtime thing. Prepare time_adjust_step to - * be within bounds. Note that a positive time_adjust means we - * want the clock to run faster. - * - * Limit the amount of the step to be in the range - * -tickadj .. +tickadj - */ - time_adjust_step = min(time_adjust_step, (long)tickadj); - time_adjust_step = max(time_adjust_step, (long)-tickadj); - } - return time_adjust_step; -} -/* in the NTP reference this is called "hardclock()" */ -void update_ntp_one_tick(void) -{ - long time_adjust_step; - - time_adjust_step = adjtime_adjustment(); - if (time_adjust_step) - /* Reduce by this step the amount of time left */ - time_adjust -= time_adjust_step; - - /* Changes by adjtime() do not take effect till next tick. */ - if (time_next_adjust != 0) { - time_adjust = time_next_adjust; - time_next_adjust = 0; + if (unlikely(time_adjust)) { + if (time_adjust > MAX_TICKADJ) { + time_adjust -= MAX_TICKADJ; + tick_length += MAX_TICKADJ_SCALED; + } else if (time_adjust < -MAX_TICKADJ) { + time_adjust += MAX_TICKADJ; + tick_length -= MAX_TICKADJ_SCALED; + } else { + time_adjust = 0; + tick_length += (s64)(time_adjust * NSEC_PER_USEC / + HZ) << TICK_LENGTH_SHIFT; + } } } @@ -213,14 +186,7 @@ void update_ntp_one_tick(void) */ u64 current_tick_length(void) { - u64 ret; - - /* calculate the finest interval NTP will allow. - */ - ret = tick_length; - ret += (u64)(adjtime_adjustment() * 1000) << TICK_LENGTH_SHIFT; - - return ret; + return tick_length; } @@ -263,7 +229,7 @@ int do_adjtimex(struct timex *txc) result = time_state; /* mostly `TIME_OK' */ /* Save for later - semantics of adjtime is to return old value */ - save_adjust = time_next_adjust ? time_next_adjust : time_adjust; + save_adjust = time_adjust; #if 0 /* STA_CLOCKERR is never set yet */ time_status &= ~STA_CLOCKERR; /* reset STA_CLOCKERR */ @@ -310,8 +276,7 @@ int do_adjtimex(struct timex *txc) if (txc->modes & ADJ_OFFSET) { /* values checked earlier */ if (txc->modes == ADJ_OFFSET_SINGLESHOT) { /* adjtime() is independent from ntp_adjtime() */ - if ((time_next_adjust = txc->offset) == 0) - time_adjust = 0; + time_adjust = txc->offset; } else if (time_status & STA_PLL) { ltemp = txc->offset; diff --git a/kernel/timer.c b/kernel/timer.c index 78d3fa10fcd..654dd5df241 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -937,8 +937,6 @@ static void update_wall_time(void) /* interpolator bits */ time_interpolator_update(clock->xtime_interval >> clock->shift); - /* increment the NTP state machine */ - update_ntp_one_tick(); /* accumulate error between NTP and clock interval */ clock->error += current_tick_length(); |