Merge branch 'fortglx/3.4/time' of git://git.linaro.org/people/jstultz/linux into timers/core

include/linux/timex.h

@@ -234,23 +234,9 @@ struct timex {
 extern unsigned long tick_usec;		/* USER_HZ period (usec) */
 extern unsigned long tick_nsec;		/* ACTHZ          period (nsec) */
 
-/*
- * phase-lock loop variables
- */
-extern int time_status;		/* clock synchronization status bits */
-
 extern void ntp_init(void);
 extern void ntp_clear(void);
 
-/**
- * ntp_synced - Returns 1 if the NTP status is not UNSYNC
- *
- */
-static inline int ntp_synced(void)
-{
-	return !(time_status & STA_UNSYNC);
-}
-
 /* Required to safely shift negative values */
 #define shift_right(x, s) ({	\
 	__typeof__(x) __x = (x);	\
@@ -264,10 +250,9 @@ static inline int ntp_synced(void)
 #define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ)
 
 /* Returns how long ticks are at present, in ns / 2^NTP_SCALE_SHIFT. */
-extern u64 tick_length;
+extern u64 ntp_tick_length(void);
 
 extern void second_overflow(void);
-extern void update_ntp_one_tick(void);
 extern int do_adjtimex(struct timex *);
 extern void hardpps(const struct timespec *, const struct timespec *);
 

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:
  */
@@ -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);