1 files changed, 37 insertions, 16 deletions

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index ae34bf51682..6db7a5ed52b 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -657,6 +657,14 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
         return 0;
 }
 
+static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
+{
+        ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset;
+        ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
+
+        return ktime_get_update_offsets(offs_real, offs_boot);
+}
+
 /*
  * Retrigger next event is called after clock was set
  *
@@ -665,22 +673,12 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
 static void retrigger_next_event(void *arg)
 {
         struct hrtimer_cpu_base *base = &__get_cpu_var(hrtimer_bases);
-        struct timespec realtime_offset, xtim, wtm, sleep;
 
         if (!hrtimer_hres_active())
                 return;
 
-        /* Optimized out for !HIGH_RES */
-        get_xtime_and_monotonic_and_sleep_offset(&xtim, &wtm, &sleep);
-        set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec);
-
-        /* Adjust CLOCK_REALTIME offset */
         raw_spin_lock(&base->lock);
-        base->clock_base[HRTIMER_BASE_REALTIME].offset =
-                timespec_to_ktime(realtime_offset);
-        base->clock_base[HRTIMER_BASE_BOOTTIME].offset =
-                timespec_to_ktime(sleep);
-
+        hrtimer_update_base(base);
         hrtimer_force_reprogram(base, 0);
         raw_spin_unlock(&base->lock);
 }
@@ -710,13 +708,25 @@ static int hrtimer_switch_to_hres(void)
                 base->clock_base[i].resolution = KTIME_HIGH_RES;
 
         tick_setup_sched_timer();
-
         /* "Retrigger" the interrupt to get things going */
         retrigger_next_event(NULL);
         local_irq_restore(flags);
         return 1;
 }
 
+/*
+ * Called from timekeeping code to reprogramm the hrtimer interrupt
+ * device. If called from the timer interrupt context we defer it to
+ * softirq context.
+ */
+void clock_was_set_delayed(void)
+{
+        struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
+
+        cpu_base->clock_was_set = 1;
+        __raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+}
+
 #else
 
 static inline int hrtimer_hres_active(void) { return 0; }
@@ -1250,11 +1260,10 @@ void hrtimer_interrupt(struct clock_event_device *dev)
         cpu_base->nr_events++;
         dev->next_event.tv64 = KTIME_MAX;
 
-        entry_time = now = ktime_get();
+        raw_spin_lock(&cpu_base->lock);
+        entry_time = now = hrtimer_update_base(cpu_base);
 retry:
         expires_next.tv64 = KTIME_MAX;
-
-        raw_spin_lock(&cpu_base->lock);
         /*
          * We set expires_next to KTIME_MAX here with cpu_base->lock
          * held to prevent that a timer is enqueued in our queue via
@@ -1330,8 +1339,12 @@ retry:
          * We need to prevent that we loop forever in the hrtimer
          * interrupt routine. We give it 3 attempts to avoid
          * overreacting on some spurious event.
+         *
+         * Acquire base lock for updating the offsets and retrieving
+         * the current time.
          */
-        now = ktime_get();
+        raw_spin_lock(&cpu_base->lock);
+        now = hrtimer_update_base(cpu_base);
         cpu_base->nr_retries++;
         if (++retries < 3)
                 goto retry;
@@ -1343,6 +1356,7 @@ retry:
          */
         cpu_base->nr_hangs++;
         cpu_base->hang_detected = 1;
+        raw_spin_unlock(&cpu_base->lock);
         delta = ktime_sub(now, entry_time);
         if (delta.tv64 > cpu_base->max_hang_time.tv64)
                 cpu_base->max_hang_time = delta;
@@ -1395,6 +1409,13 @@ void hrtimer_peek_ahead_timers(void)
 
 static void run_hrtimer_softirq(struct softirq_action *h)
 {
+        struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
+
+        if (cpu_base->clock_was_set) {
+                cpu_base->clock_was_set = 0;
+                clock_was_set();
+        }
+
         hrtimer_peek_ahead_timers();
 }