1 files changed, 26 insertions, 0 deletions

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 62aad8e1a383..476cb0c0b4a4 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -585,6 +585,18 @@ static inline void hrtimer_init_timer_hres(struct hrtimer *timer) { }
 
 #endif /* CONFIG_HIGH_RES_TIMERS */
 
+#ifdef CONFIG_TIMER_STATS
+void __timer_stats_hrtimer_set_start_info(struct hrtimer *timer, void *addr)
+{
+        if (timer->start_site)
+                return;
+
+        timer->start_site = addr;
+        memcpy(timer->start_comm, current->comm, TASK_COMM_LEN);
+        timer->start_pid = current->pid;
+}
+#endif
+
 /*
  * Counterpart to lock_timer_base above:
  */
@@ -743,6 +755,7 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
                  * reprogramming happens in the interrupt handler. This is a
                  * rare case and less expensive than a smp call.
                  */
+                timer_stats_hrtimer_clear_start_info(timer);
                 reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases);
                 __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE,
                                  reprogram);
@@ -791,6 +804,8 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
         }
         timer->expires = tim;
 
+        timer_stats_hrtimer_set_start_info(timer);
+
         enqueue_hrtimer(timer, new_base, base == new_base);
 
         unlock_hrtimer_base(timer, &flags);
@@ -925,6 +940,12 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 
         timer->base = &cpu_base->clock_base[clock_id];
         hrtimer_init_timer_hres(timer);
+
+#ifdef CONFIG_TIMER_STATS
+        timer->start_site = NULL;
+        timer->start_pid = -1;
+        memset(timer->start_comm, 0, TASK_COMM_LEN);
+#endif
 }
 EXPORT_SYMBOL_GPL(hrtimer_init);
 
@@ -1006,6 +1027,7 @@ void hrtimer_interrupt(struct clock_event_device *dev)
 
                         __remove_hrtimer(timer, base,
                                          HRTIMER_STATE_CALLBACK, 0);
+                        timer_stats_account_hrtimer(timer);
 
                         /*
                          * Note: We clear the CALLBACK bit after
@@ -1050,6 +1072,8 @@ static void run_hrtimer_softirq(struct softirq_action *h)
                 timer = list_entry(cpu_base->cb_pending.next,
                                    struct hrtimer, cb_entry);
 
+                timer_stats_account_hrtimer(timer);
+
                 fn = timer->function;
                 __remove_hrtimer(timer, timer->base, HRTIMER_STATE_CALLBACK, 0);
                 spin_unlock_irq(&cpu_base->lock);
@@ -1106,6 +1130,8 @@ static inline void run_hrtimer_queue(struct hrtimer_cpu_base *cpu_base,
                 if (base->softirq_time.tv64 <= timer->expires.tv64)
                         break;
 
+                timer_stats_account_hrtimer(timer);
+
                 fn = timer->function;
                 __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0);
                 spin_unlock_irq(&cpu_base->lock);