diff options
Diffstat (limited to 'kernel/time/ntp.c')
| -rw-r--r-- | kernel/time/ntp.c | 85 |
1 files changed, 64 insertions, 21 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index f6117a4c7cb8..6e039b144daf 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -22,13 +22,16 @@ * NTP timekeeping variables: */ +DEFINE_SPINLOCK(ntp_lock); + + /* USER_HZ period (usecs): */ unsigned long tick_usec = TICK_USEC; /* ACTHZ period (nsecs): */ unsigned long tick_nsec; -u64 tick_length; +static u64 tick_length; static u64 tick_length_base; static struct hrtimer leap_timer; @@ -49,7 +52,7 @@ static struct hrtimer leap_timer; static int time_state = TIME_OK; /* clock status bits: */ -int time_status = STA_UNSYNC; +static int time_status = STA_UNSYNC; /* TAI offset (secs): */ static long time_tai; @@ -133,7 +136,7 @@ static inline void pps_reset_freq_interval(void) /** * pps_clear - Clears the PPS state variables * - * Must be called while holding a write on the xtime_lock + * Must be called while holding a write on the ntp_lock */ static inline void pps_clear(void) { @@ -149,7 +152,7 @@ static inline void pps_clear(void) * the last PPS signal. When it reaches 0, indicate that PPS signal is * missing. * - * Must be called while holding a write on the xtime_lock + * Must be called while holding a write on the ntp_lock */ static inline void pps_dec_valid(void) { @@ -233,6 +236,17 @@ static inline void pps_fill_timex(struct timex *txc) #endif /* CONFIG_NTP_PPS */ + +/** + * ntp_synced - Returns 1 if the NTP status is not UNSYNC + * + */ +static inline int ntp_synced(void) +{ + return !(time_status & STA_UNSYNC); +} + + /* * NTP methods: */ @@ -275,7 +289,7 @@ static inline s64 ntp_update_offset_fll(s64 offset64, long secs) time_status |= STA_MODE; - return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); + return div64_long(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); } static void ntp_update_offset(long offset) @@ -330,11 +344,13 @@ static void ntp_update_offset(long offset) /** * ntp_clear - Clears the NTP state variables - * - * Must be called while holding a write on the xtime_lock */ void ntp_clear(void) { + unsigned long flags; + + spin_lock_irqsave(&ntp_lock, flags); + time_adjust = 0; /* stop active adjtime() */ time_status |= STA_UNSYNC; time_maxerror = NTP_PHASE_LIMIT; @@ -347,8 +363,23 @@ void ntp_clear(void) /* Clear PPS state variables */ pps_clear(); + spin_unlock_irqrestore(&ntp_lock, flags); + } + +u64 ntp_tick_length(void) +{ + unsigned long flags; + s64 ret; + + spin_lock_irqsave(&ntp_lock, flags); + ret = tick_length; + spin_unlock_irqrestore(&ntp_lock, flags); + return ret; +} + + /* * Leap second processing. If in leap-insert state at the end of the * day, the system clock is set back one second; if in leap-delete @@ -357,14 +388,15 @@ void ntp_clear(void) static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) { enum hrtimer_restart res = HRTIMER_NORESTART; + unsigned long flags; + int leap = 0; - write_seqlock(&xtime_lock); - + spin_lock_irqsave(&ntp_lock, flags); switch (time_state) { case TIME_OK: break; case TIME_INS: - timekeeping_leap_insert(-1); + leap = -1; time_state = TIME_OOP; printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n"); @@ -372,7 +404,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) res = HRTIMER_RESTART; break; case TIME_DEL: - timekeeping_leap_insert(1); + leap = 1; time_tai--; time_state = TIME_WAIT; printk(KERN_NOTICE @@ -387,8 +419,14 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) time_state = TIME_OK; break; } + spin_unlock_irqrestore(&ntp_lock, flags); - write_sequnlock(&xtime_lock); + /* + * We have to call this outside of the ntp_lock to keep + * the proper locking hierarchy + */ + if (leap) + timekeeping_leap_insert(leap); return res; } @@ -404,6 +442,9 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) void second_overflow(void) { s64 delta; + unsigned long flags; + + spin_lock_irqsave(&ntp_lock, flags); /* Bump the maxerror field */ time_maxerror += MAXFREQ / NSEC_PER_USEC; @@ -423,23 +464,25 @@ void second_overflow(void) pps_dec_valid(); if (!time_adjust) - return; + goto out; if (time_adjust > MAX_TICKADJ) { time_adjust -= MAX_TICKADJ; tick_length += MAX_TICKADJ_SCALED; - return; + goto out; } if (time_adjust < -MAX_TICKADJ) { time_adjust += MAX_TICKADJ; tick_length -= MAX_TICKADJ_SCALED; - return; + goto out; } tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ) << NTP_SCALE_SHIFT; time_adjust = 0; +out: + spin_unlock_irqrestore(&ntp_lock, flags); } #ifdef CONFIG_GENERIC_CMOS_UPDATE @@ -663,7 +706,7 @@ int do_adjtimex(struct timex *txc) getnstimeofday(&ts); - write_seqlock_irq(&xtime_lock); + spin_lock_irq(&ntp_lock); if (txc->modes & ADJ_ADJTIME) { long save_adjust = time_adjust; @@ -705,7 +748,7 @@ int do_adjtimex(struct timex *txc) /* fill PPS status fields */ pps_fill_timex(txc); - write_sequnlock_irq(&xtime_lock); + spin_unlock_irq(&ntp_lock); txc->time.tv_sec = ts.tv_sec; txc->time.tv_usec = ts.tv_nsec; @@ -903,7 +946,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) pts_norm = pps_normalize_ts(*phase_ts); - write_seqlock_irqsave(&xtime_lock, flags); + spin_lock_irqsave(&ntp_lock, flags); /* clear the error bits, they will be set again if needed */ time_status &= ~(STA_PPSJITTER | STA_PPSWANDER | STA_PPSERROR); @@ -916,7 +959,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) * just start the frequency interval */ if (unlikely(pps_fbase.tv_sec == 0)) { pps_fbase = *raw_ts; - write_sequnlock_irqrestore(&xtime_lock, flags); + spin_unlock_irqrestore(&ntp_lock, flags); return; } @@ -931,7 +974,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) time_status |= STA_PPSJITTER; /* restart the frequency calibration interval */ pps_fbase = *raw_ts; - write_sequnlock_irqrestore(&xtime_lock, flags); + spin_unlock_irqrestore(&ntp_lock, flags); pr_err("hardpps: PPSJITTER: bad pulse\n"); return; } @@ -948,7 +991,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) hardpps_update_phase(pts_norm.nsec); - write_sequnlock_irqrestore(&xtime_lock, flags); + spin_unlock_irqrestore(&ntp_lock, flags); } EXPORT_SYMBOL(hardpps); |