Merge branch 'v28-range-hrtimers-for-linus-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'v28-range-hrtimers-for-linus-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (37 commits)
  hrtimers: add missing docbook comments to struct hrtimer
  hrtimers: simplify hrtimer_peek_ahead_timers()
  hrtimers: fix docbook comments
  DECLARE_PER_CPU needs linux/percpu.h
  hrtimers: fix typo
  rangetimers: fix the bug reported by Ingo for real
  rangetimer: fix BUG_ON reported by Ingo
  rangetimer: fix x86 build failure for the !HRTIMERS case
  select: fix alpha OSF wrapper
  select: fix alpha OSF wrapper
  hrtimer: peek at the timer queue just before going idle
  hrtimer: make the futex() system call use the per process slack value
  hrtimer: make the nanosleep() syscall use the per process slack
  hrtimer: fix signed/unsigned bug in slack estimator
  hrtimer: show the timer ranges in /proc/timer_list
  hrtimer: incorporate feedback from Peter Zijlstra
  hrtimer: add a hrtimer_start_range() function
  hrtimer: another build fix
  hrtimer: fix build bug found by Ingo
  hrtimer: make select() and poll() use the hrtimer range feature
  ...

11 files changed, 249 insertions, 54 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 4d09355..f608356 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1018,6 +1018,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 	p->prev_utime = cputime_zero;
 	p->prev_stime = cputime_zero;
 
+	p->default_timer_slack_ns = current->timer_slack_ns;
+
 #ifdef CONFIG_DETECT_SOFTLOCKUP
 	p->last_switch_count = 0;
 	p->last_switch_timestamp = 0;
diff --git a/kernel/futex.c b/kernel/futex.c
index 7d1136e..8af1002 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1296,13 +1296,16 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 		if (!abs_time)
 			schedule();
 		else {
+			unsigned long slack;
+			slack = current->timer_slack_ns;
+			if (rt_task(current))
+				slack = 0;
 			hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC,
 						HRTIMER_MODE_ABS);
 			hrtimer_init_sleeper(&t, current);
-			t.timer.expires = *abs_time;
+			hrtimer_set_expires_range_ns(&t.timer, *abs_time, slack);
 
-			hrtimer_start(&t.timer, t.timer.expires,
-						HRTIMER_MODE_ABS);
+			hrtimer_start_expires(&t.timer, HRTIMER_MODE_ABS);
 			if (!hrtimer_active(&t.timer))
 				t.task = NULL;
 
@@ -1404,7 +1407,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 		hrtimer_init_on_stack(&to->timer, CLOCK_REALTIME,
 				      HRTIMER_MODE_ABS);
 		hrtimer_init_sleeper(to, current);
-		to->timer.expires = *time;
+		hrtimer_set_expires(&to->timer, *time);
 	}
 
 	q.pi_state = NULL;
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 95978f4..2b465df 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -517,7 +517,7 @@ static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
 		if (!base->first)
 			continue;
 		timer = rb_entry(base->first, struct hrtimer, node);
-		expires = ktime_sub(timer->expires, base->offset);
+		expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
 		if (expires.tv64 < cpu_base->expires_next.tv64)
 			cpu_base->expires_next = expires;
 	}
@@ -539,10 +539,10 @@ static int hrtimer_reprogram(struct hrtimer *timer,
 			     struct hrtimer_clock_base *base)
 {
 	ktime_t *expires_next = &__get_cpu_var(hrtimer_bases).expires_next;
-	ktime_t expires = ktime_sub(timer->expires, base->offset);
+	ktime_t expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
 	int res;
 
-	WARN_ON_ONCE(timer->expires.tv64 < 0);
+	WARN_ON_ONCE(hrtimer_get_expires_tv64(timer) < 0);
 
 	/*
 	 * When the callback is running, we do not reprogram the clock event
@@ -795,7 +795,7 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
 	u64 orun = 1;
 	ktime_t delta;
 
-	delta = ktime_sub(now, timer->expires);
+	delta = ktime_sub(now, hrtimer_get_expires(timer));
 
 	if (delta.tv64 < 0)
 		return 0;
@@ -807,8 +807,8 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
 		s64 incr = ktime_to_ns(interval);
 
 		orun = ktime_divns(delta, incr);
-		timer->expires = ktime_add_ns(timer->expires, incr * orun);
-		if (timer->expires.tv64 > now.tv64)
+		hrtimer_add_expires_ns(timer, incr * orun);
+		if (hrtimer_get_expires_tv64(timer) > now.tv64)
 			return orun;
 		/*
 		 * This (and the ktime_add() below) is the
@@ -816,7 +816,7 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
 		 */
 		orun++;
 	}
-	timer->expires = ktime_add_safe(timer->expires, interval);
+	hrtimer_add_expires(timer, interval);
 
 	return orun;
 }
@@ -848,7 +848,8 @@ static void enqueue_hrtimer(struct hrtimer *timer,
 		 * We dont care about collisions. Nodes with
 		 * the same expiry time stay together.
 		 */
-		if (timer->expires.tv64 < entry->expires.tv64) {
+		if (hrtimer_get_expires_tv64(timer) <
+				hrtimer_get_expires_tv64(entry)) {
 			link = &(*link)->rb_left;
 		} else {
 			link = &(*link)->rb_right;
@@ -945,9 +946,10 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
 }
 
 /**
- * hrtimer_start - (re)start an relative timer on the current CPU
+ * hrtimer_start_range_ns - (re)start an hrtimer on the current CPU
  * @timer:	the timer to be added
  * @tim:	expiry time
+ * @delta_ns:	"slack" range for the timer
  * @mode:	expiry mode: absolute (HRTIMER_ABS) or relative (HRTIMER_REL)
  *
  * Returns:
@@ -955,7 +957,8 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
  *  1 when the timer was active
  */
 int
-hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
+hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, unsigned long delta_ns,
+			const enum hrtimer_mode mode)
 {
 	struct hrtimer_clock_base *base, *new_base;
 	unsigned long flags;
@@ -983,7 +986,7 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
 #endif
 	}
 
-	timer->expires = tim;
+	hrtimer_set_expires_range_ns(timer, tim, delta_ns);
 
 	timer_stats_hrtimer_set_start_info(timer);
 
@@ -1016,8 +1019,26 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(hrtimer_start_range_ns);
+
+/**
+ * hrtimer_start - (re)start an hrtimer on the current CPU
+ * @timer:	the timer to be added
+ * @tim:	expiry time
+ * @mode:	expiry mode: absolute (HRTIMER_ABS) or relative (HRTIMER_REL)
+ *
+ * Returns:
+ *  0 on success
+ *  1 when the timer was active
+ */
+int
+hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
+{
+	return hrtimer_start_range_ns(timer, tim, 0, mode);
+}
 EXPORT_SYMBOL_GPL(hrtimer_start);
 
+
 /**
  * hrtimer_try_to_cancel - try to deactivate a timer
  * @timer:	hrtimer to stop
@@ -1077,7 +1098,7 @@ ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
 	ktime_t rem;
 
 	base = lock_hrtimer_base(timer, &flags);
-	rem = ktime_sub(timer->expires, base->get_time());
+	rem = hrtimer_expires_remaining(timer);
 	unlock_hrtimer_base(timer, &flags);
 
 	return rem;
@@ -1109,7 +1130,7 @@ ktime_t hrtimer_get_next_event(void)
 				continue;
 
 			timer = rb_entry(base->first, struct hrtimer, node);
-			delta.tv64 = timer->expires.tv64;
+			delta.tv64 = hrtimer_get_expires_tv64(timer);
 			delta = ktime_sub(delta, base->get_time());
 			if (delta.tv64 < mindelta.tv64)
 				mindelta.tv64 = delta.tv64;
@@ -1310,10 +1331,23 @@ void hrtimer_interrupt(struct clock_event_device *dev)
 
 			timer = rb_entry(node, struct hrtimer, node);
 
-			if (basenow.tv64 < timer->expires.tv64) {
+			/*
+			 * The immediate goal for using the softexpires is
+			 * minimizing wakeups, not running timers at the
+			 * earliest interrupt after their soft expiration.
+			 * This allows us to avoid using a Priority Search
+			 * Tree, which can answer a stabbing querry for
+			 * overlapping intervals and instead use the simple
+			 * BST we already have.
+			 * We don't add extra wakeups by delaying timers that
+			 * are right-of a not yet expired timer, because that
+			 * timer will have to trigger a wakeup anyway.
+			 */
+
+			if (basenow.tv64 < hrtimer_get_softexpires_tv64(timer)) {
 				ktime_t expires;
 
-				expires = ktime_sub(timer->expires,
+				expires = ktime_sub(hrtimer_get_expires(timer),
 						    base->offset);
 				if (expires.tv64 < expires_next.tv64)
 					expires_next = expires;
@@ -1349,6 +1383,30 @@ void hrtimer_interrupt(struct clock_event_device *dev)
 		raise_softirq(HRTIMER_SOFTIRQ);
 }
 
+/**
+ * hrtimer_peek_ahead_timers -- run soft-expired timers now
+ *
+ * hrtimer_peek_ahead_timers will peek at the timer queue of
+ * the current cpu and check if there are any timers for which
+ * the soft expires time has passed. If any such timers exist,
+ * they are run immediately and then removed from the timer queue.
+ *
+ */
+void hrtimer_peek_ahead_timers(void)
+{
+	struct tick_device *td;
+	unsigned long flags;
+
+	if (!hrtimer_hres_active())
+		return;
+
+	local_irq_save(flags);
+	td = &__get_cpu_var(tick_cpu_device);
+	if (td && td->evtdev)
+		hrtimer_interrupt(td->evtdev);
+	local_irq_restore(flags);
+}
+
 static void run_hrtimer_softirq(struct softirq_action *h)
 {
 	run_hrtimer_pending(&__get_cpu_var(hrtimer_bases));
@@ -1414,7 +1472,8 @@ void hrtimer_run_queues(void)
 			struct hrtimer *timer;
 
 			timer = rb_entry(node, struct hrtimer, node);
-			if (base->softirq_time.tv64 <= timer->expires.tv64)
+			if (base->softirq_time.tv64 <=
+					hrtimer_get_expires_tv64(timer))
 				break;
 
 			if (timer->cb_mode == HRTIMER_CB_SOFTIRQ) {
@@ -1462,7 +1521,7 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 
 	do {
 		set_current_state(TASK_INTERRUPTIBLE);
-		hrtimer_start(&t->timer, t->timer.expires, mode);
+		hrtimer_start_expires(&t->timer, mode);
 		if (!hrtimer_active(&t->timer))
 			t->task = NULL;
 
@@ -1484,7 +1543,7 @@ static int update_rmtp(struct hrtimer *timer, struct timespec __user *rmtp)
 	struct timespec rmt;
 	ktime_t rem;
 
-	rem = ktime_sub(timer->expires, timer->base->get_time());
+	rem = hrtimer_expires_remaining(timer);
 	if (rem.tv64 <= 0)
 		return 0;
 	rmt = ktime_to_timespec(rem);
@@ -1503,7 +1562,7 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 
 	hrtimer_init_on_stack(&t.timer, restart->nanosleep.index,
 				HRTIMER_MODE_ABS);
-	t.timer.expires.tv64 = restart->nanosleep.expires;
+	hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
 
 	if (do_nanosleep(&t, HRTIMER_MODE_ABS))
 		goto out;
@@ -1528,9 +1587,14 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 	struct restart_block *restart;
 	struct hrtimer_sleeper t;
 	int ret = 0;
+	unsigned long slack;
+
+	slack = current->timer_slack_ns;
+	if (rt_task(current))
+		slack = 0;
 
 	hrtimer_init_on_stack(&t.timer, clockid, mode);
-	t.timer.expires = timespec_to_ktime(*rqtp);
+	hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack);
 	if (do_nanosleep(&t, mode))
 		goto out;
 
@@ -1550,7 +1614,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 	restart->fn = hrtimer_nanosleep_restart;
 	restart->nanosleep.index = t.timer.base->index;
 	restart->nanosleep.rmtp = rmtp;
-	restart->nanosleep.expires = t.timer.expires.tv64;
+	restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);
 
 	ret = -ERESTART_RESTARTBLOCK;
 out:
@@ -1752,3 +1816,103 @@ void __init hrtimers_init(void)
 #endif
 }
 
+/**
+ * schedule_hrtimeout_range - sleep until timeout
+ * @expires:	timeout value (ktime_t)
+ * @delta:	slack in expires timeout (ktime_t)
+ * @mode:	timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
+ *
+ * Make the current task sleep until the given expiry time has
+ * elapsed. The routine will return immediately unless
+ * the current task state has been set (see set_current_state()).
+ *
+ * The @delta argument gives the kernel the freedom to schedule the
+ * actual wakeup to a time that is both power and performance friendly.
+ * The kernel give the normal best effort behavior for "@expires+@delta",
+ * but may decide to fire the timer earlier, but no earlier than @expires.
+ *
+ * You can set the task state as follows -
+ *
+ * %TASK_UNINTERRUPTIBLE - at least @timeout time is guaranteed to
+ * pass before the routine returns.
+ *
+ * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
+ * delivered to the current task.
+ *
+ * The current task state is guaranteed to be TASK_RUNNING when this
+ * routine returns.
+ *
+ * Returns 0 when the timer has expired otherwise -EINTR
+ */
+int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
+			       const enum hrtimer_mode mode)
+{
+	struct hrtimer_sleeper t;
+
+	/*
+	 * Optimize when a zero timeout value is given. It does not
+	 * matter whether this is an absolute or a relative time.
+	 */
+	if (expires && !expires->tv64) {
+		__set_current_state(TASK_RUNNING);
+		return 0;
+	}
+
+	/*
+	 * A NULL parameter means "inifinte"
+	 */
+	if (!expires) {
+		schedule();
+		__set_current_state(TASK_RUNNING);
+		return -EINTR;
+	}
+
+	hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, mode);
+	hrtimer_set_expires_range_ns(&t.timer, *expires, delta);
+
+	hrtimer_init_sleeper(&t, current);
+
+	hrtimer_start_expires(&t.timer, mode);
+	if (!hrtimer_active(&t.timer))
+		t.task = NULL;
+
+	if (likely(t.task))
+		schedule();
+
+	hrtimer_cancel(&t.timer);
+	destroy_hrtimer_on_stack(&t.timer);
+
+	__set_current_state(TASK_RUNNING);
+
+	return !t.task ? 0 : -EINTR;
+}
+EXPORT_SYMBOL_GPL(schedule_hrtimeout_range);
+
+/**
+ * schedule_hrtimeout - sleep until timeout
+ * @expires:	timeout value (ktime_t)
+ * @mode:	timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
+ *
+ * Make the current task sleep until the given expiry time has
+ * elapsed. The routine will return immediately unless
+ * the current task state has been set (see set_current_state()).
+ *
+ * You can set the task state as follows -
+ *
+ * %TASK_UNINTERRUPTIBLE - at least @timeout time is guaranteed to
+ * pass before the routine returns.
+ *
+ * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
+ * delivered to the current task.
+ *
+ * The current task state is guaranteed to be TASK_RUNNING when this
+ * routine returns.
+ *
+ * Returns 0 when the timer has expired otherwise -EINTR
+ */
+int __sched schedule_hrtimeout(ktime_t *expires,
+			       const enum hrtimer_mode mode)
+{
+	return schedule_hrtimeout_range(expires, 0, mode);
+}
+EXPORT_SYMBOL_GPL(schedule_hrtimeout);
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index b931d7c..5e79c66 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -639,7 +639,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
 	    (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
 		timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
 
-	remaining = ktime_sub(timer->expires, now);
+	remaining = ktime_sub(hrtimer_get_expires(timer), now);
 	/* Return 0 only, when the timer is expired and not pending */
 	if (remaining.tv64 <= 0) {
 		/*
@@ -733,7 +733,7 @@ common_timer_set(struct k_itimer *timr, int flags,
 	hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
 	timr->it.real.timer.function = posix_timer_fn;
 
-	timer->expires = timespec_to_ktime(new_setting->it_value);
+	hrtimer_set_expires(timer, timespec_to_ktime(new_setting->it_value));
 
 	/* Convert interval */
 	timr->it.real.interval = timespec_to_ktime(new_setting->it_interval);
@@ -742,14 +742,12 @@ common_timer_set(struct k_itimer *timr, int flags,
 	if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
 		/* Setup correct expiry time for relative timers */
 		if (mode == HRTIMER_MODE_REL) {
-			timer->expires =
-				ktime_add_safe(timer->expires,
-					       timer->base->get_time());
+			hrtimer_add_expires(timer, timer->base->get_time());
 		}
 		return 0;
 	}
 
-	hrtimer_start(timer, timer->expires, mode);
+	hrtimer_start_expires(timer, mode);
 	return 0;
 }
 
diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c
index 6522ae5..69d9cb9 100644
--- a/kernel/rtmutex.c
+++ b/kernel/rtmutex.c
@@ -631,8 +631,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
 
 	/* Setup the timer, when timeout != NULL */
 	if (unlikely(timeout)) {
-		hrtimer_start(&timeout->timer, timeout->timer.expires,
-			      HRTIMER_MODE_ABS);
+		hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);
 		if (!hrtimer_active(&timeout->timer))
 			timeout->task = NULL;
 	}
diff --git a/kernel/sched.c b/kernel/sched.c
index 945a97b..1645c72 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -227,9 +227,8 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
 
 		now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
 		hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
-		hrtimer_start(&rt_b->rt_period_timer,
-			      rt_b->rt_period_timer.expires,
-			      HRTIMER_MODE_ABS);
+		hrtimer_start_expires(&rt_b->rt_period_timer,
+				HRTIMER_MODE_ABS);
 	}
 	spin_unlock(&rt_b->rt_runtime_lock);
 }
@@ -1071,7 +1070,7 @@ static void hrtick_start(struct rq *rq, u64 delay)
 	struct hrtimer *timer = &rq->hrtick_timer;
 	ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
 
-	timer->expires = time;
+	hrtimer_set_expires(timer, time);
 
 	if (rq == this_rq()) {
 		hrtimer_restart(timer);
diff --git a/kernel/sys.c b/kernel/sys.c
index 53879cd..31deba8 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1716,6 +1716,16 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
 		case PR_SET_TSC:
 			error = SET_TSC_CTL(arg2);
 			break;
+		case PR_GET_TIMERSLACK:
+			error = current->timer_slack_ns;
+			break;
+		case PR_SET_TIMERSLACK:
+			if (arg2 <= 0)
+				current->timer_slack_ns =
+					current->default_timer_slack_ns;
+			else
+				current->timer_slack_ns = arg2;
+			break;
 		default:
 			error = -EINVAL;
 			break;
diff --git a/kernel/time.c b/kernel/time.c
index 6a08660..d63a433 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -669,3 +669,21 @@ EXPORT_SYMBOL(get_jiffies_64);
 #endif
 
 EXPORT_SYMBOL(jiffies);
+
+/*
+ * Add two timespec values and do a safety check for overflow.
+ * It's assumed that both values are valid (>= 0)
+ */
+struct timespec timespec_add_safe(const struct timespec lhs,
+				  const struct timespec rhs)
+{
+	struct timespec res;
+
+	set_normalized_timespec(&res, lhs.tv_sec + rhs.tv_sec,
+				lhs.tv_nsec + rhs.tv_nsec);
+
+	if (res.tv_sec < lhs.tv_sec || res.tv_sec < rhs.tv_sec)
+		res.tv_sec = TIME_T_MAX;
+
+	return res;
+}
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 1a20715..8ff15e5 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -142,8 +142,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
 		time_state = TIME_OOP;
 		printk(KERN_NOTICE "Clock: "
 		       "inserting leap second 23:59:60 UTC\n");
-		leap_timer.expires = ktime_add_ns(leap_timer.expires,
-						  NSEC_PER_SEC);
+		hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC);
 		res = HRTIMER_RESTART;
 		break;
 	case TIME_DEL:
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 727c1ae..5bbb104 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -300,7 +300,7 @@ void tick_nohz_stop_sched_tick(int inidle)
 				goto out;
 			}
 
-			ts->idle_tick = ts->sched_timer.expires;
+			ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
 			ts->tick_stopped = 1;
 			ts->idle_jiffies = last_jiffies;
 			rcu_enter_nohz();
@@ -380,21 +380,21 @@ ktime_t tick_nohz_get_sleep_length(void)
 static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
 {
 	hrtimer_cancel(&ts->sched_timer);
-	ts->sched_timer.expires = ts->idle_tick;
+	hrtimer_set_expires(&ts->sched_timer, ts->idle_tick);
 
 	while (1) {
 		/* Forward the time to expire in the future */
 		hrtimer_forward(&ts->sched_timer, now, tick_period);
 
 		if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
-			hrtimer_start(&ts->sched_timer,
-				      ts->sched_timer.expires,
+			hrtimer_start_expires(&ts->sched_timer,
 				      HRTIMER_MODE_ABS);
 			/* Check, if the timer was already in the past */
 			if (hrtimer_active(&ts->sched_timer))
 				break;
 		} else {
-			if (!tick_program_event(ts->sched_timer.expires, 0))
+			if (!tick_program_event(
+				hrtimer_get_expires(&ts->sched_timer), 0))
 				break;
 		}
 		/* Update jiffies and reread time */
@@ -456,14 +456,16 @@ void tick_nohz_restart_sched_tick(void)
 	 */
 	ts->tick_stopped  = 0;
 	ts->idle_exittime = now;
+
 	tick_nohz_restart(ts, now);
+
 	local_irq_enable();
 }
 
 static int tick_nohz_reprogram(struct tick_sched *ts, ktime_t now)
 {
 	hrtimer_forward(&ts->sched_timer, now, tick_period);
-	return tick_program_event(ts->sched_timer.expires, 0);
+	return tick_program_event(hrtimer_get_expires(&ts->sched_timer), 0);
 }
 
 /*
@@ -542,7 +544,7 @@ static void tick_nohz_switch_to_nohz(void)
 	next = tick_init_jiffy_update();
 
 	for (;;) {
-		ts->sched_timer.expires = next;
+		hrtimer_set_expires(&ts->sched_timer, next);
 		if (!tick_program_event(next, 0))
 			break;
 		next = ktime_add(next, tick_period);
@@ -577,7 +579,7 @@ static void tick_nohz_kick_tick(int cpu)
 	 * already reached or less/equal than the tick period.
 	 */
 	now = ktime_get();
-	delta =	ktime_sub(ts->sched_timer.expires, now);
+	delta =	ktime_sub(hrtimer_get_expires(&ts->sched_timer), now);
 	if (delta.tv64 <= tick_period.tv64)
 		return;
 
@@ -678,16 +680,15 @@ void tick_setup_sched_timer(void)
 	ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU;
 
 	/* Get the next period (per cpu) */
-	ts->sched_timer.expires = tick_init_jiffy_update();
+	hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update());
 	offset = ktime_to_ns(tick_period) >> 1;
 	do_div(offset, num_possible_cpus());
 	offset *= smp_processor_id();
-	ts->sched_timer.expires = ktime_add_ns(ts->sched_timer.expires, offset);
+	hrtimer_add_expires_ns(&ts->sched_timer, offset);
 
 	for (;;) {
 		hrtimer_forward(&ts->sched_timer, now, tick_period);
-		hrtimer_start(&ts->sched_timer, ts->sched_timer.expires,
-			      HRTIMER_MODE_ABS);
+		hrtimer_start_expires(&ts->sched_timer, HRTIMER_MODE_ABS);
 		/* Check, if the timer was already in the past */
 		if (hrtimer_active(&ts->sched_timer))
 			break;
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index f642691..a999b92 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -66,9 +66,11 @@ print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
 	SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
 #endif
 	SEQ_printf(m, "\n");
-	SEQ_printf(m, " # expires at %Lu nsecs [in %Ld nsecs]\n",
-		(unsigned long long)ktime_to_ns(timer->expires),
-		(long long)(ktime_to_ns(timer->expires) - now));
+	SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n",
+		(unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)),
+		(unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)),
+		(long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now),
+		(long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now));
 }
 
 static void