diff options
| -rw-r--r-- | include/linux/time.h | 4 | ||||
| -rw-r--r-- | include/linux/timex.h | 9 | ||||
| -rw-r--r-- | kernel/time/ntp.c | 23 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 2 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 6 |
5 files changed, 25 insertions, 19 deletions
diff --git a/include/linux/time.h b/include/linux/time.h index 2091a19f165..d32ef0ad4c0 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -174,6 +174,10 @@ static inline void timespec_add_ns(struct timespec *a, u64 ns) { ns += a->tv_nsec; while(unlikely(ns >= NSEC_PER_SEC)) { + /* The following asm() prevents the compiler from + * optimising this loop into a modulo operation. */ + asm("" : "+r"(ns)); + ns -= NSEC_PER_SEC; a->tv_sec++; } diff --git a/include/linux/timex.h b/include/linux/timex.h index c3f374786a4..8ea3e71ba7f 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -232,14 +232,7 @@ static inline int ntp_synced(void) #else #define NTP_INTERVAL_FREQ (HZ) #endif - -#define CLOCK_TICK_OVERFLOW (LATCH * HZ - CLOCK_TICK_RATE) -#define CLOCK_TICK_ADJUST (((s64)CLOCK_TICK_OVERFLOW * NSEC_PER_SEC) / \ - (s64)CLOCK_TICK_RATE) - -/* Because using NSEC_PER_SEC would be too easy */ -#define NTP_INTERVAL_LENGTH ((((s64)TICK_USEC * NSEC_PER_USEC * USER_HZ) + \ - CLOCK_TICK_ADJUST) / NTP_INTERVAL_FREQ) +#define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ) /* Returns how long ticks are at present, in ns / 2^(SHIFT_SCALE-10). */ extern u64 current_tick_length(void); diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index c88b5910e7a..5fd9b946977 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -42,12 +42,13 @@ long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */ long time_freq; /* frequency offset (scaled ppm)*/ static long time_reftime; /* time at last adjustment (s) */ long time_adjust; +static long ntp_tick_adj; static void ntp_update_frequency(void) { u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ) << TICK_LENGTH_SHIFT; - second_length += (s64)CLOCK_TICK_ADJUST << TICK_LENGTH_SHIFT; + second_length += (s64)ntp_tick_adj << TICK_LENGTH_SHIFT; second_length += (s64)time_freq << (TICK_LENGTH_SHIFT - SHIFT_NSEC); tick_length_base = second_length; @@ -342,14 +343,16 @@ int do_adjtimex(struct timex *txc) freq_adj = shift_right(freq_adj, time_constant * 2 + (SHIFT_PLL + 2) * 2 - SHIFT_NSEC); if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) { + u64 utemp64; temp64 = time_offset << (SHIFT_NSEC - SHIFT_FLL); if (time_offset < 0) { - temp64 = -temp64; - do_div(temp64, mtemp); - freq_adj -= temp64; + utemp64 = -temp64; + do_div(utemp64, mtemp); + freq_adj -= utemp64; } else { - do_div(temp64, mtemp); - freq_adj += temp64; + utemp64 = temp64; + do_div(utemp64, mtemp); + freq_adj += utemp64; } } freq_adj += time_freq; @@ -400,3 +403,11 @@ leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0) notify_cmos_timer(); return(result); } + +static int __init ntp_tick_adj_setup(char *str) +{ + ntp_tick_adj = simple_strtol(str, NULL, 0); + return 1; +} + +__setup("ntp_tick_adj=", ntp_tick_adj_setup); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 2968298f8f3..686da821d37 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -640,7 +640,7 @@ void tick_cancel_sched_timer(int cpu) if (ts->sched_timer.base) hrtimer_cancel(&ts->sched_timer); - ts->tick_stopped = 0; + ts->nohz_mode = NOHZ_MODE_INACTIVE; } #endif /* HIGH_RES_TIMERS */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 1af9fb050fe..671af612b76 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -187,8 +187,7 @@ static void change_clocksource(void) clock->error = 0; clock->xtime_nsec = 0; - clocksource_calculate_interval(clock, - (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT)); + clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); tick_clock_notify(); @@ -245,8 +244,7 @@ void __init timekeeping_init(void) ntp_clear(); clock = clocksource_get_next(); - clocksource_calculate_interval(clock, - (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT)); + clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); clock->cycle_last = clocksource_read(clock); xtime.tv_sec = sec; |