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

Pull the leap second fixes from Thomas Gleixner:
 "It's a rather large series, but well discussed, refined and reviewed.
  It got a massive testing by John, Prarit and tip.

  In theory we could split it into two parts.  The first two patches

    f55a6faa3843: hrtimer: Provide clock_was_set_delayed()
    4873fa070ae8: timekeeping: Fix leapsecond triggered load spike issue

  are merely preventing the stuff loops forever issues, which people
  have observed.

  But there is no point in delaying the other 4 commits which achieve
  full correctness into 3.6 as they are tagged for stable anyway.  And I
  rather prefer to have the full fixes merged in bulk than a "prevent
  the observable wreckage and deal with the hidden fallout later"
  approach."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Update hrtimer base offsets each hrtimer_interrupt
  timekeeping: Provide hrtimer update function
  hrtimers: Move lock held region in hrtimer_interrupt()
  timekeeping: Maintain ktime_t based offsets for hrtimers
  timekeeping: Fix leapsecond triggered load spike issue
  hrtimer: Provide clock_was_set_delayed()

1 files changed, 61 insertions, 2 deletions

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 6f46a00a1e8..269b1fe5f2a 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -70,6 +70,12 @@ struct timekeeper {
 	/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
 	struct timespec raw_time;
 
+	/* Offset clock monotonic -> clock realtime */
+	ktime_t offs_real;
+
+	/* Offset clock monotonic -> clock boottime */
+	ktime_t offs_boot;
+
 	/* Seqlock for all timekeeper values */
 	seqlock_t lock;
 };
@@ -172,6 +178,14 @@ static inline s64 timekeeping_get_ns_raw(void)
 	return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
 }
 
+static void update_rt_offset(void)
+{
+	struct timespec tmp, *wtm = &timekeeper.wall_to_monotonic;
+
+	set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec);
+	timekeeper.offs_real = timespec_to_ktime(tmp);
+}
+
 /* must hold write on timekeeper.lock */
 static void timekeeping_update(bool clearntp)
 {
@@ -179,6 +193,7 @@ static void timekeeping_update(bool clearntp)
 		timekeeper.ntp_error = 0;
 		ntp_clear();
 	}
+	update_rt_offset();
 	update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
 			 timekeeper.clock, timekeeper.mult);
 }
@@ -604,6 +619,7 @@ void __init timekeeping_init(void)
 	}
 	set_normalized_timespec(&timekeeper.wall_to_monotonic,
 				-boot.tv_sec, -boot.tv_nsec);
+	update_rt_offset();
 	timekeeper.total_sleep_time.tv_sec = 0;
 	timekeeper.total_sleep_time.tv_nsec = 0;
 	write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -612,6 +628,12 @@ void __init timekeeping_init(void)
 /* time in seconds when suspend began */
 static struct timespec timekeeping_suspend_time;
 
+static void update_sleep_time(struct timespec t)
+{
+	timekeeper.total_sleep_time = t;
+	timekeeper.offs_boot = timespec_to_ktime(t);
+}
+
 /**
  * __timekeeping_inject_sleeptime - Internal function to add sleep interval
  * @delta: pointer to a timespec delta value
@@ -630,8 +652,7 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
 	timekeeper.xtime = timespec_add(timekeeper.xtime, *delta);
 	timekeeper.wall_to_monotonic =
 			timespec_sub(timekeeper.wall_to_monotonic, *delta);
-	timekeeper.total_sleep_time = timespec_add(
-					timekeeper.total_sleep_time, *delta);
+	update_sleep_time(timespec_add(timekeeper.total_sleep_time, *delta));
 }
 
 
@@ -963,6 +984,8 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
 		leap = second_overflow(timekeeper.xtime.tv_sec);
 		timekeeper.xtime.tv_sec += leap;
 		timekeeper.wall_to_monotonic.tv_sec -= leap;
+		if (leap)
+			clock_was_set_delayed();
 	}
 
 	/* Accumulate raw time */
@@ -1079,6 +1102,8 @@ static void update_wall_time(void)
 		leap = second_overflow(timekeeper.xtime.tv_sec);
 		timekeeper.xtime.tv_sec += leap;
 		timekeeper.wall_to_monotonic.tv_sec -= leap;
+		if (leap)
+			clock_was_set_delayed();
 	}
 
 	timekeeping_update(false);
@@ -1246,6 +1271,40 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
 	} while (read_seqretry(&timekeeper.lock, seq));
 }
 
+#ifdef CONFIG_HIGH_RES_TIMERS
+/**
+ * ktime_get_update_offsets - hrtimer helper
+ * @offs_real:	pointer to storage for monotonic -> realtime offset
+ * @offs_boot:	pointer to storage for monotonic -> boottime offset
+ *
+ * Returns current monotonic time and updates the offsets
+ * Called from hrtimer_interupt() or retrigger_next_event()
+ */
+ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
+{
+	ktime_t now;
+	unsigned int seq;
+	u64 secs, nsecs;
+
+	do {
+		seq = read_seqbegin(&timekeeper.lock);
+
+		secs = timekeeper.xtime.tv_sec;
+		nsecs = timekeeper.xtime.tv_nsec;
+		nsecs += timekeeping_get_ns();
+		/* If arch requires, add in gettimeoffset() */
+		nsecs += arch_gettimeoffset();
+
+		*offs_real = timekeeper.offs_real;
+		*offs_boot = timekeeper.offs_boot;
+	} while (read_seqretry(&timekeeper.lock, seq));
+
+	now = ktime_add_ns(ktime_set(secs, 0), nsecs);
+	now = ktime_sub(now, *offs_real);
+	return now;
+}
+#endif
+
 /**
  * ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format
  */