Merge branch 'timers/range-hrtimers' into v28-range-hrtimers-for-linus-v2

Conflicts:

	kernel/time/tick-sched.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

11 files changed, 249 insertions, 54 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 4d093552dd6e..f6083561dfe0 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 7d1136e97c14..8af10027514b 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 95978f48e039..2b465dfde426 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 b931d7cedbfa..5e79c662294b 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 6522ae5b14a2..69d9cb921ffa 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 d906f72b42d2..bfa87918380f 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);
 }
@@ -1064,7 +1063,7 @@ 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 53879cdae483..31deba8f7d16 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 6a08660b4fac..d63a4336fad6 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 1a20715bfd6e..8ff15e5d486b 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 727c1ae0517a..5bbb1044f847 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 f6426911e35a..a999b92a1277 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