2 files changed, 50 insertions, 1 deletions

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index c145ed643bca..eabcbd781433 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -78,6 +78,11 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
                         .get_time = &ktime_get_boottime,
                         .resolution = KTIME_LOW_RES,
                 },
+                {
+                        .index = CLOCK_REALTIME_COS,
+                        .get_time = &ktime_get_real,
+                        .resolution = KTIME_LOW_RES,
+                },
         }
 };
 
@@ -85,6 +90,7 @@ static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
         [CLOCK_REALTIME]        = HRTIMER_BASE_REALTIME,
         [CLOCK_MONOTONIC]       = HRTIMER_BASE_MONOTONIC,
         [CLOCK_BOOTTIME]        = HRTIMER_BASE_BOOTTIME,
+        [CLOCK_REALTIME_COS]    = HRTIMER_BASE_REALTIME_COS,
 };
 
 static inline int hrtimer_clockid_to_base(clockid_t clock_id)
@@ -110,6 +116,7 @@ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
         base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim;
         base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = mono;
         base->clock_base[HRTIMER_BASE_BOOTTIME].softirq_time = boot;
+        base->clock_base[HRTIMER_BASE_REALTIME_COS].softirq_time = xtim;
 }
 
 /*
@@ -479,6 +486,8 @@ static inline void debug_deactivate(struct hrtimer *timer)
         trace_hrtimer_cancel(timer);
 }
 
+static void hrtimer_expire_cancelable(struct hrtimer_cpu_base *cpu_base);
+
 /* High resolution timer related functions */
 #ifdef CONFIG_HIGH_RES_TIMERS
 
@@ -715,9 +724,14 @@ 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())
+        if (!hrtimer_hres_active()) {
+                raw_spin_lock(&base->lock);
+                hrtimer_expire_cancelable(base);
+                raw_spin_unlock(&base->lock);
                 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);
 
@@ -727,6 +741,10 @@ static void retrigger_next_event(void *arg)
                 timespec_to_ktime(realtime_offset);
         base->clock_base[HRTIMER_BASE_BOOTTIME].offset =
                 timespec_to_ktime(sleep);
+        base->clock_base[HRTIMER_BASE_REALTIME_COS].offset =
+                timespec_to_ktime(realtime_offset);
+
+        hrtimer_expire_cancelable(base);
 
         hrtimer_force_reprogram(base, 0);
         raw_spin_unlock(&base->lock);
@@ -1222,6 +1240,22 @@ static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
         timer->state &= ~HRTIMER_STATE_CALLBACK;
 }
 
+static void hrtimer_expire_cancelable(struct hrtimer_cpu_base *cpu_base)
+{
+        struct timerqueue_node *node;
+        struct hrtimer_clock_base *base;
+        ktime_t now = ktime_get_real();
+
+        base = &cpu_base->clock_base[HRTIMER_BASE_REALTIME_COS];
+
+        while ((node = timerqueue_getnext(&base->active))) {
+                        struct hrtimer *timer;
+
+                        timer = container_of(node, struct hrtimer, node);
+                        __run_hrtimer(timer, &now);
+        }
+}
+
 #ifdef CONFIG_HIGH_RES_TIMERS
 
 /*
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index a61b8fa2d39a..342408cf68dd 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1099,6 +1099,21 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
 }
 
 /**
+ * ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format
+ */
+ktime_t ktime_get_monotonic_offset(void)
+{
+        unsigned long seq;
+        struct timespec wtom;
+
+        do {
+                seq = read_seqbegin(&xtime_lock);
+                wtom = wall_to_monotonic;
+        } while (read_seqretry(&xtime_lock, seq));
+        return timespec_to_ktime(wtom);
+}
+
+/**
  * xtime_update() - advances the timekeeping infrastructure
  * @ticks:      number of ticks, that have elapsed since the last call.
  *