8 files changed, 146 insertions, 37 deletions

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index c5dde988c0ce..cc47812d3feb 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -642,21 +642,9 @@ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
  * and expiry check is done in the hrtimer_interrupt or in the softirq.
  */
 static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
-                                            struct hrtimer_clock_base *base,
-                                            int wakeup)
+                                            struct hrtimer_clock_base *base)
 {
-        if (base->cpu_base->hres_active && hrtimer_reprogram(timer, base)) {
-                if (wakeup) {
-                        raw_spin_unlock(&base->cpu_base->lock);
-                        raise_softirq_irqoff(HRTIMER_SOFTIRQ);
-                        raw_spin_lock(&base->cpu_base->lock);
-                } else
-                        __raise_softirq_irqoff(HRTIMER_SOFTIRQ);
-
-                return 1;
-        }
-
-        return 0;
+        return base->cpu_base->hres_active && hrtimer_reprogram(timer, base);
 }
 
 static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
@@ -737,8 +725,7 @@ static inline int hrtimer_switch_to_hres(void) { return 0; }
 static inline void
 hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
 static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
-                                            struct hrtimer_clock_base *base,
-                                            int wakeup)
+                                            struct hrtimer_clock_base *base)
 {
         return 0;
 }
@@ -997,8 +984,21 @@ int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
          *
          * XXX send_remote_softirq() ?
          */
-        if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases))
-                hrtimer_enqueue_reprogram(timer, new_base, wakeup);
+        if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases)
+                && hrtimer_enqueue_reprogram(timer, new_base)) {
+                if (wakeup) {
+                        /*
+                         * We need to drop cpu_base->lock to avoid a
+                         * lock ordering issue vs. rq->lock.
+                         */
+                        raw_spin_unlock(&new_base->cpu_base->lock);
+                        raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+                        local_irq_restore(flags);
+                        return ret;
+                } else {
+                        __raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+                }
+        }
 
         unlock_hrtimer_base(timer, &flags);
 
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 165d47698477..8fd709c9bb58 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -1417,8 +1417,10 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
                 while (!signal_pending(current)) {
                         if (timer.it.cpu.expires.sched == 0) {
                                 /*
-                                 * Our timer fired and was reset.
+                                 * Our timer fired and was reset, below
+                                 * deletion can not fail.
                                  */
+                                posix_cpu_timer_del(&timer);
                                 spin_unlock_irq(&timer.it_lock);
                                 return 0;
                         }
@@ -1436,9 +1438,26 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
                  * We were interrupted by a signal.
                  */
                 sample_to_timespec(which_clock, timer.it.cpu.expires, rqtp);
-                posix_cpu_timer_set(&timer, 0, &zero_it, it);
+                error = posix_cpu_timer_set(&timer, 0, &zero_it, it);
+                if (!error) {
+                        /*
+                         * Timer is now unarmed, deletion can not fail.
+                         */
+                        posix_cpu_timer_del(&timer);
+                }
                 spin_unlock_irq(&timer.it_lock);
 
+                while (error == TIMER_RETRY) {
+                        /*
+                         * We need to handle case when timer was or is in the
+                         * middle of firing. In other cases we already freed
+                         * resources.
+                         */
+                        spin_lock_irq(&timer.it_lock);
+                        error = posix_cpu_timer_del(&timer);
+                        spin_unlock_irq(&timer.it_lock);
+                }
+
                 if ((it->it_value.tv_sec | it->it_value.tv_nsec) == 0) {
                         /*
                          * It actually did fire already.
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 69185ae6b701..10349d5f2ec3 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -997,7 +997,7 @@ SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
 
         err = kc->clock_adj(which_clock, &ktx);
 
-        if (!err && copy_to_user(utx, &ktx, sizeof(ktx)))
+        if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
                 return -EFAULT;
 
         return err;
diff --git a/kernel/time.c b/kernel/time.c
index d226c6a3fd28..c2a27dd93142 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -115,6 +115,12 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv,
 }
 
 /*
+ * Indicates if there is an offset between the system clock and the hardware
+ * clock/persistent clock/rtc.
+ */
+int persistent_clock_is_local;
+
+/*
  * Adjust the time obtained from the CMOS to be UTC time instead of
  * local time.
  *
@@ -135,6 +141,8 @@ static inline void warp_clock(void)
         struct timespec adjust;
 
         adjust = current_kernel_time();
+        if (sys_tz.tz_minuteswest != 0)
+                persistent_clock_is_local = 1;
         adjust.tv_sec += sys_tz.tz_minuteswest * 60;
         do_settimeofday(&adjust);
 }
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 8601f0db1261..24510d84efd7 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -12,6 +12,11 @@ config CLOCKSOURCE_WATCHDOG
 config ARCH_CLOCKSOURCE_DATA
         bool
 
+# Platforms has a persistent clock
+config ALWAYS_USE_PERSISTENT_CLOCK
+        bool
+        default n
+
 # Timekeeping vsyscall support
 config GENERIC_TIME_VSYSCALL
         bool
@@ -38,6 +43,10 @@ config GENERIC_CLOCKEVENTS_BUILD
         default y
         depends on GENERIC_CLOCKEVENTS
 
+# Architecture can handle broadcast in a driver-agnostic way
+config ARCH_HAS_TICK_BROADCAST
+        bool
+
 # Clockevents broadcasting infrastructure
 config GENERIC_CLOCKEVENTS_BROADCAST
         bool
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 24174b4d669b..b10a42bb0165 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -15,6 +15,7 @@
 #include <linux/time.h>
 #include <linux/mm.h>
 #include <linux/module.h>
+#include <linux/rtc.h>
 
 #include "tick-internal.h"
 
@@ -483,8 +484,7 @@ out:
         return leap;
 }
 
-#ifdef CONFIG_GENERIC_CMOS_UPDATE
-
+#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC)
 static void sync_cmos_clock(struct work_struct *work);
 
 static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock);
@@ -510,14 +510,26 @@ static void sync_cmos_clock(struct work_struct *work)
         }
 
         getnstimeofday(&now);
-        if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2)
-                fail = update_persistent_clock(now);
+        if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) {
+                struct timespec adjust = now;
+
+                fail = -ENODEV;
+                if (persistent_clock_is_local)
+                        adjust.tv_sec -= (sys_tz.tz_minuteswest * 60);
+#ifdef CONFIG_GENERIC_CMOS_UPDATE
+                fail = update_persistent_clock(adjust);
+#endif
+#ifdef CONFIG_RTC_SYSTOHC
+                if (fail == -ENODEV)
+                        fail = rtc_set_ntp_time(adjust);
+#endif
+        }
 
         next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec - (TICK_NSEC / 2);
         if (next.tv_nsec <= 0)
                 next.tv_nsec += NSEC_PER_SEC;
 
-        if (!fail)
+        if (!fail || fail == -ENODEV)
                 next.tv_sec = 659;
         else
                 next.tv_sec = 0;
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index f113755695e2..2fb8cb88df8d 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -18,6 +18,7 @@
 #include <linux/percpu.h>
 #include <linux/profile.h>
 #include <linux/sched.h>
+#include <linux/smp.h>
 
 #include "tick-internal.h"
 
@@ -86,6 +87,22 @@ int tick_is_broadcast_device(struct clock_event_device *dev)
         return (dev && tick_broadcast_device.evtdev == dev);
 }
 
+static void err_broadcast(const struct cpumask *mask)
+{
+        pr_crit_once("Failed to broadcast timer tick. Some CPUs may be unresponsive.\n");
+}
+
+static void tick_device_setup_broadcast_func(struct clock_event_device *dev)
+{
+        if (!dev->broadcast)
+                dev->broadcast = tick_broadcast;
+        if (!dev->broadcast) {
+                pr_warn_once("%s depends on broadcast, but no broadcast function available\n",
+                             dev->name);
+                dev->broadcast = err_broadcast;
+        }
+}
+
 /*
  * Check, if the device is disfunctional and a place holder, which
  * needs to be handled by the broadcast device.
@@ -105,6 +122,7 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu)
          */
         if (!tick_device_is_functional(dev)) {
                 dev->event_handler = tick_handle_periodic;
+                tick_device_setup_broadcast_func(dev);
                 cpumask_set_cpu(cpu, tick_get_broadcast_mask());
                 tick_broadcast_start_periodic(tick_broadcast_device.evtdev);
                 ret = 1;
@@ -116,15 +134,33 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu)
                  */
                 if (!(dev->features & CLOCK_EVT_FEAT_C3STOP)) {
                         int cpu = smp_processor_id();
-
                         cpumask_clear_cpu(cpu, tick_get_broadcast_mask());
                         tick_broadcast_clear_oneshot(cpu);
+                } else {
+                        tick_device_setup_broadcast_func(dev);
                 }
         }
         raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
         return ret;
 }
 
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+int tick_receive_broadcast(void)
+{
+        struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
+        struct clock_event_device *evt = td->evtdev;
+
+        if (!evt)
+                return -ENODEV;
+
+        if (!evt->event_handler)
+                return -EINVAL;
+
+        evt->event_handler(evt);
+        return 0;
+}
+#endif
+
 /*
  * Broadcast the event to the cpus, which are set in the mask (mangled).
  */
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index cbc6acb0db3f..1e35515a875e 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -29,6 +29,9 @@ static struct timekeeper timekeeper;
 /* flag for if timekeeping is suspended */
 int __read_mostly timekeeping_suspended;
 
+/* Flag for if there is a persistent clock on this platform */
+bool __read_mostly persistent_clock_exist = false;
+
 static inline void tk_normalize_xtime(struct timekeeper *tk)
 {
         while (tk->xtime_nsec >= ((u64)NSEC_PER_SEC << tk->shift)) {
@@ -264,19 +267,18 @@ static void timekeeping_forward_now(struct timekeeper *tk)
 }
 
 /**
- * getnstimeofday - Returns the time of day in a timespec
+ * __getnstimeofday - Returns the time of day in a timespec.
  * @ts:         pointer to the timespec to be set
  *
- * Returns the time of day in a timespec.
+ * Updates the time of day in the timespec.
+ * Returns 0 on success, or -ve when suspended (timespec will be undefined).
  */
-void getnstimeofday(struct timespec *ts)
+int __getnstimeofday(struct timespec *ts)
 {
         struct timekeeper *tk = &timekeeper;
         unsigned long seq;
         s64 nsecs = 0;
 
-        WARN_ON(timekeeping_suspended);
-
         do {
                 seq = read_seqbegin(&tk->lock);
 
@@ -287,6 +289,26 @@ void getnstimeofday(struct timespec *ts)
 
         ts->tv_nsec = 0;
         timespec_add_ns(ts, nsecs);
+
+        /*
+         * Do not bail out early, in case there were callers still using
+         * the value, even in the face of the WARN_ON.
+         */
+        if (unlikely(timekeeping_suspended))
+                return -EAGAIN;
+        return 0;
+}
+EXPORT_SYMBOL(__getnstimeofday);
+
+/**
+ * getnstimeofday - Returns the time of day in a timespec.
+ * @ts:         pointer to the timespec to be set
+ *
+ * Returns the time of day in a timespec (WARN if suspended).
+ */
+void getnstimeofday(struct timespec *ts)
+{
+        WARN_ON(__getnstimeofday(ts));
 }
 EXPORT_SYMBOL(getnstimeofday);
 
@@ -640,12 +662,14 @@ void __init timekeeping_init(void)
         struct timespec now, boot, tmp;
 
         read_persistent_clock(&now);
+
         if (!timespec_valid_strict(&now)) {
                 pr_warn("WARNING: Persistent clock returned invalid value!\n"
                         "         Check your CMOS/BIOS settings.\n");
                 now.tv_sec = 0;
                 now.tv_nsec = 0;
-        }
+        } else if (now.tv_sec || now.tv_nsec)
+                persistent_clock_exist = true;
 
         read_boot_clock(&boot);
         if (!timespec_valid_strict(&boot)) {
@@ -718,11 +742,12 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
 {
         struct timekeeper *tk = &timekeeper;
         unsigned long flags;
-        struct timespec ts;
 
-        /* Make sure we don't set the clock twice */
-        read_persistent_clock(&ts);
-        if (!(ts.tv_sec == 0 && ts.tv_nsec == 0))
+        /*
+         * Make sure we don't set the clock twice, as timekeeping_resume()
+         * already did it
+         */
+        if (has_persistent_clock())
                 return;
 
         write_seqlock_irqsave(&tk->lock, flags);