1 files changed, 26 insertions, 24 deletions

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 0237a556eb1f..d2a7296c8251 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -501,6 +501,7 @@ int hrtimer_cancel(struct hrtimer *timer)
 
                 if (ret >= 0)
                         return ret;
+                cpu_relax();
         }
 }
 
@@ -606,6 +607,9 @@ static inline void run_hrtimer_queue(struct hrtimer_base *base)
 {
         struct rb_node *node;
 
+        if (!base->first)
+                return;
+
         if (base->get_softirq_time)
                 base->softirq_time = base->get_softirq_time();
 
@@ -655,29 +659,28 @@ void hrtimer_run_queues(void)
 /*
  * Sleep related functions:
  */
-
-struct sleep_hrtimer {
-        struct hrtimer timer;
-        struct task_struct *task;
-        int expired;
-};
-
-static int nanosleep_wakeup(struct hrtimer *timer)
+static int hrtimer_wakeup(struct hrtimer *timer)
 {
-        struct sleep_hrtimer *t =
-                container_of(timer, struct sleep_hrtimer, timer);
+        struct hrtimer_sleeper *t =
+                container_of(timer, struct hrtimer_sleeper, timer);
+        struct task_struct *task = t->task;
 
-        t->expired = 1;
-        wake_up_process(t->task);
+        t->task = NULL;
+        if (task)
+                wake_up_process(task);
 
         return HRTIMER_NORESTART;
 }
 
-static int __sched do_nanosleep(struct sleep_hrtimer *t, enum hrtimer_mode mode)
+void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, task_t *task)
 {
-        t->timer.function = nanosleep_wakeup;
-        t->task = current;
-        t->expired = 0;
+        sl->timer.function = hrtimer_wakeup;
+        sl->task = task;
+}
+
+static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
+{
+        hrtimer_init_sleeper(t, current);
 
         do {
                 set_current_state(TASK_INTERRUPTIBLE);
@@ -685,18 +688,17 @@ static int __sched do_nanosleep(struct sleep_hrtimer *t, enum hrtimer_mode mode)
 
                 schedule();
 
-                if (unlikely(!t->expired)) {
-                        hrtimer_cancel(&t->timer);
-                        mode = HRTIMER_ABS;
-                }
-        } while (!t->expired && !signal_pending(current));
+                hrtimer_cancel(&t->timer);
+                mode = HRTIMER_ABS;
+
+        } while (t->task && !signal_pending(current));
 
-        return t->expired;
+        return t->task == NULL;
 }
 
 static long __sched nanosleep_restart(struct restart_block *restart)
 {
-        struct sleep_hrtimer t;
+        struct hrtimer_sleeper t;
         struct timespec __user *rmtp;
         struct timespec tu;
         ktime_t time;
@@ -729,7 +731,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
                        const enum hrtimer_mode mode, const clockid_t clockid)
 {
         struct restart_block *restart;
-        struct sleep_hrtimer t;
+        struct hrtimer_sleeper t;
         struct timespec tu;
         ktime_t rem;