Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer core updates from Thomas Gleixner.

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ia64: vsyscall: Add missing paranthesis
  alarmtimer: Don't call rtc_timer_init() when CONFIG_RTC_CLASS=n
  x86: vdso: Put declaration before code
  x86-64: Inline vdso clock_gettime helpers
  x86-64: Simplify and optimize vdso clock_gettime monotonic variants
  kernel-time: fix s/then/than/ spelling errors
  time: remove no_sync_cmos_clock
  time: Avoid scary backtraces when warning of > 11% adj
  alarmtimer: Make sure we initialize the rtctimer
  ntp: Fix leap-second hrtimer livelock
  x86, tsc: Skip refined tsc calibration on systems with reliable TSC
  rtc: Provide flag for rtc devices that don't support UIE
  ia64: vsyscall: Use seqcount instead of seqlock
  x86: vdso: Use seqcount instead of seqlock
  x86: vdso: Remove bogus locking in update_vsyscall_tz()
  time: Remove bogus comments
  time: Fix change_clocksource locking
  time: x86: Fix race switching from vsyscall to non-vsyscall clock

5 files changed, 77 insertions, 124 deletions

diff --git a/kernel/time.c b/kernel/time.c
index 73e416db0a1e..ba744cf80696 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -163,7 +163,6 @@ int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz)
                 return error;
 
         if (tz) {
-                /* SMP safe, global irq locking makes it work. */
                 sys_tz = *tz;
                 update_vsyscall_tz();
                 if (firsttime) {
@@ -173,12 +172,7 @@ int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz)
                 }
         }
         if (tv)
-        {
-                /* SMP safe, again the code in arch/foo/time.c should
-                 * globally block out interrupts when it runs.
-                 */
                 return do_settimeofday(tv);
-        }
         return 0;
 }
 
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 8a46f5d64504..8a538c55fc7b 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -96,6 +96,11 @@ static int alarmtimer_rtc_add_device(struct device *dev,
         return 0;
 }
 
+static inline void alarmtimer_rtc_timer_init(void)
+{
+        rtc_timer_init(&rtctimer, NULL, NULL);
+}
+
 static struct class_interface alarmtimer_rtc_interface = {
         .add_dev = &alarmtimer_rtc_add_device,
 };
@@ -117,6 +122,7 @@ static inline struct rtc_device *alarmtimer_get_rtcdev(void)
 #define rtcdev (NULL)
 static inline int alarmtimer_rtc_interface_setup(void) { return 0; }
 static inline void alarmtimer_rtc_interface_remove(void) { }
+static inline void alarmtimer_rtc_timer_init(void) { }
 #endif
 
 /**
@@ -783,6 +789,8 @@ static int __init alarmtimer_init(void)
                 .nsleep         = alarm_timer_nsleep,
         };
 
+        alarmtimer_rtc_timer_init();
+
         posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock);
         posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock);
 
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index a45ca167ab24..c9583382141a 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -500,7 +500,7 @@ static u32 clocksource_max_adjustment(struct clocksource *cs)
 {
         u64 ret;
         /*
-         * We won't try to correct for more then 11% adjustments (110,000 ppm),
+         * We won't try to correct for more than 11% adjustments (110,000 ppm),
          */
         ret = (u64)cs->mult * 11;
         do_div(ret,100);
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 6e039b144daf..f03fd83b170b 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -34,8 +34,6 @@ unsigned long			tick_nsec;
 static u64                      tick_length;
 static u64                      tick_length_base;
 
-static struct hrtimer           leap_timer;
-
 #define MAX_TICKADJ             500LL           /* usecs */
 #define MAX_TICKADJ_SCALED \
         (((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
@@ -381,70 +379,63 @@ u64 ntp_tick_length(void)
 
 
 /*
- * 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
- * state, the system clock is set ahead one second.
+ * this routine handles the overflow of the microsecond field
+ *
+ * The tricky bits of code to handle the accurate clock support
+ * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
+ * They were originally developed for SUN and DEC kernels.
+ * All the kudos should go to Dave for this stuff.
+ *
+ * Also handles leap second processing, and returns leap offset
  */
-static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
+int second_overflow(unsigned long secs)
 {
-        enum hrtimer_restart res = HRTIMER_NORESTART;
-        unsigned long flags;
+        s64 delta;
         int leap = 0;
+        unsigned long flags;
 
         spin_lock_irqsave(&ntp_lock, flags);
+
+        /*
+         * 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
+         * state, the system clock is set ahead one second.
+         */
         switch (time_state) {
         case TIME_OK:
+                if (time_status & STA_INS)
+                        time_state = TIME_INS;
+                else if (time_status & STA_DEL)
+                        time_state = TIME_DEL;
                 break;
         case TIME_INS:
-                leap = -1;
-                time_state = TIME_OOP;
-                printk(KERN_NOTICE
-                        "Clock: inserting leap second 23:59:60 UTC\n");
-                hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC);
-                res = HRTIMER_RESTART;
+                if (secs % 86400 == 0) {
+                        leap = -1;
+                        time_state = TIME_OOP;
+                        printk(KERN_NOTICE
+                                "Clock: inserting leap second 23:59:60 UTC\n");
+                }
                 break;
         case TIME_DEL:
-                leap = 1;
-                time_tai--;
-                time_state = TIME_WAIT;
-                printk(KERN_NOTICE
-                        "Clock: deleting leap second 23:59:59 UTC\n");
+                if ((secs + 1) % 86400 == 0) {
+                        leap = 1;
+                        time_tai--;
+                        time_state = TIME_WAIT;
+                        printk(KERN_NOTICE
+                                "Clock: deleting leap second 23:59:59 UTC\n");
+                }
                 break;
         case TIME_OOP:
                 time_tai++;
                 time_state = TIME_WAIT;
-                /* fall through */
+                break;
+
         case TIME_WAIT:
                 if (!(time_status & (STA_INS | STA_DEL)))
                         time_state = TIME_OK;
                 break;
         }
-        spin_unlock_irqrestore(&ntp_lock, flags);
 
-        /*
-         * We have to call this outside of the ntp_lock to keep
-         * the proper locking hierarchy
-         */
-        if (leap)
-                timekeeping_leap_insert(leap);
-
-        return res;
-}
-
-/*
- * this routine handles the overflow of the microsecond field
- *
- * The tricky bits of code to handle the accurate clock support
- * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
- * They were originally developed for SUN and DEC kernels.
- * All the kudos should go to Dave for this stuff.
- */
-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;
@@ -481,15 +472,17 @@ void second_overflow(void)
         tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ)
                                                          << NTP_SCALE_SHIFT;
         time_adjust = 0;
+
+
+
 out:
         spin_unlock_irqrestore(&ntp_lock, flags);
+
+        return leap;
 }
 
 #ifdef CONFIG_GENERIC_CMOS_UPDATE
 
-/* Disable the cmos update - used by virtualization and embedded */
-int no_sync_cmos_clock  __read_mostly;
-
 static void sync_cmos_clock(struct work_struct *work);
 
 static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock);
@@ -536,35 +529,13 @@ static void sync_cmos_clock(struct work_struct *work)
 
 static void notify_cmos_timer(void)
 {
-        if (!no_sync_cmos_clock)
-                schedule_delayed_work(&sync_cmos_work, 0);
+        schedule_delayed_work(&sync_cmos_work, 0);
 }
 
 #else
 static inline void notify_cmos_timer(void) { }
 #endif
 
-/*
- * Start the leap seconds timer:
- */
-static inline void ntp_start_leap_timer(struct timespec *ts)
-{
-        long now = ts->tv_sec;
-
-        if (time_status & STA_INS) {
-                time_state = TIME_INS;
-                now += 86400 - now % 86400;
-                hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
-
-                return;
-        }
-
-        if (time_status & STA_DEL) {
-                time_state = TIME_DEL;
-                now += 86400 - (now + 1) % 86400;
-                hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
-        }
-}
 
 /*
  * Propagate a new txc->status value into the NTP state:
@@ -589,22 +560,6 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts)
         time_status &= STA_RONLY;
         time_status |= txc->status & ~STA_RONLY;
 
-        switch (time_state) {
-        case TIME_OK:
-                ntp_start_leap_timer(ts);
-                break;
-        case TIME_INS:
-        case TIME_DEL:
-                time_state = TIME_OK;
-                ntp_start_leap_timer(ts);
-        case TIME_WAIT:
-                if (!(time_status & (STA_INS | STA_DEL)))
-                        time_state = TIME_OK;
-                break;
-        case TIME_OOP:
-                hrtimer_restart(&leap_timer);
-                break;
-        }
 }
 /*
  * Called with the xtime lock held, so we can access and modify
@@ -686,9 +641,6 @@ int do_adjtimex(struct timex *txc)
                     (txc->tick <  900000/USER_HZ ||
                      txc->tick > 1100000/USER_HZ))
                         return -EINVAL;
-
-                if (txc->modes & ADJ_STATUS && time_state != TIME_OK)
-                        hrtimer_cancel(&leap_timer);
         }
 
         if (txc->modes & ADJ_SETOFFSET) {
@@ -1010,6 +962,4 @@ __setup("ntp_tick_adj=", ntp_tick_adj_setup);
 void __init ntp_init(void)
 {
         ntp_clear();
-        hrtimer_init(&leap_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
-        leap_timer.function = ntp_leap_second;
 }
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 15be32e19c6e..d66b21308f7c 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -184,18 +184,6 @@ static void timekeeping_update(bool clearntp)
 }
 
 
-void timekeeping_leap_insert(int leapsecond)
-{
-        unsigned long flags;
-
-        write_seqlock_irqsave(&timekeeper.lock, flags);
-        timekeeper.xtime.tv_sec += leapsecond;
-        timekeeper.wall_to_monotonic.tv_sec -= leapsecond;
-        timekeeping_update(false);
-        write_sequnlock_irqrestore(&timekeeper.lock, flags);
-
-}
-
 /**
  * timekeeping_forward_now - update clock to the current time
  *
@@ -448,9 +436,12 @@ EXPORT_SYMBOL(timekeeping_inject_offset);
 static int change_clocksource(void *data)
 {
         struct clocksource *new, *old;
+        unsigned long flags;
 
         new = (struct clocksource *) data;
 
+        write_seqlock_irqsave(&timekeeper.lock, flags);
+
         timekeeping_forward_now();
         if (!new->enable || new->enable(new) == 0) {
                 old = timekeeper.clock;
@@ -458,6 +449,10 @@ static int change_clocksource(void *data)
                 if (old->disable)
                         old->disable(old);
         }
+        timekeeping_update(true);
+
+        write_sequnlock_irqrestore(&timekeeper.lock, flags);
+
         return 0;
 }
 
@@ -827,7 +822,7 @@ static void timekeeping_adjust(s64 offset)
         int adj;
 
         /*
-         * The point of this is to check if the error is greater then half
+         * The point of this is to check if the error is greater than half
          * an interval.
          *
          * First we shift it down from NTP_SHIFT to clocksource->shifted nsecs.
@@ -835,7 +830,7 @@ static void timekeeping_adjust(s64 offset)
          * Note we subtract one in the shift, so that error is really error*2.
          * This "saves" dividing(shifting) interval twice, but keeps the
          * (error > interval) comparison as still measuring if error is
-         * larger then half an interval.
+         * larger than half an interval.
          *
          * Note: It does not "save" on aggravation when reading the code.
          */
@@ -843,7 +838,7 @@ static void timekeeping_adjust(s64 offset)
         if (error > interval) {
                 /*
                  * We now divide error by 4(via shift), which checks if
-                 * the error is greater then twice the interval.
+                 * the error is greater than twice the interval.
                  * If it is greater, we need a bigadjust, if its smaller,
                  * we can adjust by 1.
                  */
@@ -874,13 +869,15 @@ static void timekeeping_adjust(s64 offset)
         } else /* No adjustment needed */
                 return;
 
-        WARN_ONCE(timekeeper.clock->maxadj &&
-                        (timekeeper.mult + adj > timekeeper.clock->mult +
-                                                timekeeper.clock->maxadj),
-                        "Adjusting %s more then 11%% (%ld vs %ld)\n",
+        if (unlikely(timekeeper.clock->maxadj &&
+                        (timekeeper.mult + adj >
+                        timekeeper.clock->mult + timekeeper.clock->maxadj))) {
+                printk_once(KERN_WARNING
+                        "Adjusting %s more than 11%% (%ld vs %ld)\n",
                         timekeeper.clock->name, (long)timekeeper.mult + adj,
                         (long)timekeeper.clock->mult +
                                 timekeeper.clock->maxadj);
+        }
         /*
          * So the following can be confusing.
          *
@@ -952,7 +949,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
         u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
         u64 raw_nsecs;
 
-        /* If the offset is smaller then a shifted interval, do nothing */
+        /* If the offset is smaller than a shifted interval, do nothing */
         if (offset < timekeeper.cycle_interval<<shift)
                 return offset;
 
@@ -962,9 +959,11 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
 
         timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;
         while (timekeeper.xtime_nsec >= nsecps) {
+                int leap;
                 timekeeper.xtime_nsec -= nsecps;
                 timekeeper.xtime.tv_sec++;
-                second_overflow();
+                leap = second_overflow(timekeeper.xtime.tv_sec);
+                timekeeper.xtime.tv_sec += leap;
         }
 
         /* Accumulate raw time */
@@ -1018,13 +1017,13 @@ static void update_wall_time(void)
          * With NO_HZ we may have to accumulate many cycle_intervals
          * (think "ticks") worth of time at once. To do this efficiently,
          * we calculate the largest doubling multiple of cycle_intervals
-         * that is smaller then the offset. We then accumulate that
+         * that is smaller than the offset.  We then accumulate that
          * chunk in one go, and then try to consume the next smaller
          * doubled multiple.
          */
         shift = ilog2(offset) - ilog2(timekeeper.cycle_interval);
         shift = max(0, shift);
-        /* Bound shift to one less then what overflows tick_length */
+        /* Bound shift to one less than what overflows tick_length */
         maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
         shift = min(shift, maxshift);
         while (offset >= timekeeper.cycle_interval) {
@@ -1072,12 +1071,14 @@ static void update_wall_time(void)
 
         /*
          * Finally, make sure that after the rounding
-         * xtime.tv_nsec isn't larger then NSEC_PER_SEC
+         * xtime.tv_nsec isn't larger than NSEC_PER_SEC
          */
         if (unlikely(timekeeper.xtime.tv_nsec >= NSEC_PER_SEC)) {
+                int leap;
                 timekeeper.xtime.tv_nsec -= NSEC_PER_SEC;
                 timekeeper.xtime.tv_sec++;
-                second_overflow();
+                leap = second_overflow(timekeeper.xtime.tv_sec);
+                timekeeper.xtime.tv_sec += leap;
         }
 
         timekeeping_update(false);