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-rw-r--r--kernel/time/clocksource.c57
-rw-r--r--kernel/time/ntp.c1
-rw-r--r--kernel/time/tick-broadcast.c24
-rw-r--r--kernel/time/tick-sched.c17
-rw-r--r--kernel/time/timekeeping.c8
5 files changed, 72 insertions, 35 deletions
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index e713ef7d19a7..50a8736757f3 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -181,6 +181,7 @@ static int finished_booting;
#ifdef CONFIG_CLOCKSOURCE_WATCHDOG
static void clocksource_watchdog_work(struct work_struct *work);
+static void clocksource_select(void);
static LIST_HEAD(watchdog_list);
static struct clocksource *watchdog;
@@ -301,13 +302,30 @@ static void clocksource_watchdog(unsigned long data)
if (!(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES) &&
(cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) &&
(watchdog->flags & CLOCK_SOURCE_IS_CONTINUOUS)) {
+ /* Mark it valid for high-res. */
cs->flags |= CLOCK_SOURCE_VALID_FOR_HRES;
+
+ /*
+ * clocksource_done_booting() will sort it if
+ * finished_booting is not set yet.
+ */
+ if (!finished_booting)
+ continue;
+
/*
- * We just marked the clocksource as highres-capable,
- * notify the rest of the system as well so that we
- * transition into high-res mode:
+ * If this is not the current clocksource let
+ * the watchdog thread reselect it. Due to the
+ * change to high res this clocksource might
+ * be preferred now. If it is the current
+ * clocksource let the tick code know about
+ * that change.
*/
- tick_clock_notify();
+ if (cs != curr_clocksource) {
+ cs->flags |= CLOCK_SOURCE_RESELECT;
+ schedule_work(&watchdog_work);
+ } else {
+ tick_clock_notify();
+ }
}
}
@@ -404,19 +422,25 @@ static void clocksource_dequeue_watchdog(struct clocksource *cs)
spin_unlock_irqrestore(&watchdog_lock, flags);
}
-static int clocksource_watchdog_kthread(void *data)
+static int __clocksource_watchdog_kthread(void)
{
struct clocksource *cs, *tmp;
unsigned long flags;
LIST_HEAD(unstable);
+ int select = 0;
- mutex_lock(&clocksource_mutex);
spin_lock_irqsave(&watchdog_lock, flags);
- list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list)
+ list_for_each_entry_safe(cs, tmp, &watchdog_list, wd_list) {
if (cs->flags & CLOCK_SOURCE_UNSTABLE) {
list_del_init(&cs->wd_list);
list_add(&cs->wd_list, &unstable);
+ select = 1;
+ }
+ if (cs->flags & CLOCK_SOURCE_RESELECT) {
+ cs->flags &= ~CLOCK_SOURCE_RESELECT;
+ select = 1;
}
+ }
/* Check if the watchdog timer needs to be stopped. */
clocksource_stop_watchdog();
spin_unlock_irqrestore(&watchdog_lock, flags);
@@ -426,6 +450,14 @@ static int clocksource_watchdog_kthread(void *data)
list_del_init(&cs->wd_list);
__clocksource_change_rating(cs, 0);
}
+ return select;
+}
+
+static int clocksource_watchdog_kthread(void *data)
+{
+ mutex_lock(&clocksource_mutex);
+ if (__clocksource_watchdog_kthread())
+ clocksource_select();
mutex_unlock(&clocksource_mutex);
return 0;
}
@@ -445,7 +477,7 @@ static void clocksource_enqueue_watchdog(struct clocksource *cs)
static inline void clocksource_dequeue_watchdog(struct clocksource *cs) { }
static inline void clocksource_resume_watchdog(void) { }
-static inline int clocksource_watchdog_kthread(void *data) { return 0; }
+static inline int __clocksource_watchdog_kthread(void) { return 0; }
static bool clocksource_is_watchdog(struct clocksource *cs) { return false; }
#endif /* CONFIG_CLOCKSOURCE_WATCHDOG */
@@ -647,16 +679,11 @@ static int __init clocksource_done_booting(void)
{
mutex_lock(&clocksource_mutex);
curr_clocksource = clocksource_default_clock();
- mutex_unlock(&clocksource_mutex);
-
finished_booting = 1;
-
/*
* Run the watchdog first to eliminate unstable clock sources
*/
- clocksource_watchdog_kthread(NULL);
-
- mutex_lock(&clocksource_mutex);
+ __clocksource_watchdog_kthread();
clocksource_select();
mutex_unlock(&clocksource_mutex);
return 0;
@@ -789,7 +816,6 @@ static void __clocksource_change_rating(struct clocksource *cs, int rating)
list_del(&cs->list);
cs->rating = rating;
clocksource_enqueue(cs);
- clocksource_select();
}
/**
@@ -801,6 +827,7 @@ void clocksource_change_rating(struct clocksource *cs, int rating)
{
mutex_lock(&clocksource_mutex);
__clocksource_change_rating(cs, rating);
+ clocksource_select();
mutex_unlock(&clocksource_mutex);
}
EXPORT_SYMBOL(clocksource_change_rating);
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 12ff13a838c6..8f5b3b98577b 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -874,7 +874,6 @@ static void hardpps_update_phase(long error)
void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
{
struct pps_normtime pts_norm, freq_norm;
- unsigned long flags;
pts_norm = pps_normalize_ts(*phase_ts);
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 4430fa695b48..218bcb565fed 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -157,7 +157,10 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu)
dev->event_handler = tick_handle_periodic;
tick_device_setup_broadcast_func(dev);
cpumask_set_cpu(cpu, tick_broadcast_mask);
- tick_broadcast_start_periodic(bc);
+ if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
+ tick_broadcast_start_periodic(bc);
+ else
+ tick_broadcast_setup_oneshot(bc);
ret = 1;
} else {
/*
@@ -583,6 +586,12 @@ again:
}
}
+ /*
+ * Remove the current cpu from the pending mask. The event is
+ * delivered immediately in tick_do_broadcast() !
+ */
+ cpumask_clear_cpu(smp_processor_id(), tick_broadcast_pending_mask);
+
/* Take care of enforced broadcast requests */
cpumask_or(tmpmask, tmpmask, tick_broadcast_force_mask);
cpumask_clear(tick_broadcast_force_mask);
@@ -654,8 +663,8 @@ void tick_broadcast_oneshot_control(unsigned long reason)
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) {
- WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask));
if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_oneshot_mask)) {
+ WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask));
clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
/*
* We only reprogram the broadcast timer if we
@@ -672,8 +681,6 @@ void tick_broadcast_oneshot_control(unsigned long reason)
} else {
if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_oneshot_mask)) {
clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT);
- if (dev->next_event.tv64 == KTIME_MAX)
- goto out;
/*
* The cpu which was handling the broadcast
* timer marked this cpu in the broadcast
@@ -688,6 +695,11 @@ void tick_broadcast_oneshot_control(unsigned long reason)
goto out;
/*
+ * Bail out if there is no next event.
+ */
+ if (dev->next_event.tv64 == KTIME_MAX)
+ goto out;
+ /*
* If the pending bit is not set, then we are
* either the CPU handling the broadcast
* interrupt or we got woken by something else.
@@ -771,10 +783,6 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
bc->event_handler = tick_handle_oneshot_broadcast;
- /* Take the do_timer update */
- if (!tick_nohz_full_cpu(cpu))
- tick_do_timer_cpu = cpu;
-
/*
* We must be careful here. There might be other CPUs
* waiting for periodic broadcast. We need to set the
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index f4208138fbf4..69601726a745 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -178,6 +178,11 @@ static bool can_stop_full_tick(void)
*/
if (!sched_clock_stable) {
trace_tick_stop(0, "unstable sched clock\n");
+ /*
+ * Don't allow the user to think they can get
+ * full NO_HZ with this machine.
+ */
+ WARN_ONCE(1, "NO_HZ FULL will not work with unstable sched clock");
return false;
}
#endif
@@ -306,7 +311,7 @@ static int __cpuinit tick_nohz_cpu_down_callback(struct notifier_block *nfb,
* we can't safely shutdown that CPU.
*/
if (have_nohz_full_mask && tick_do_timer_cpu == cpu)
- return -EINVAL;
+ return NOTIFY_BAD;
break;
}
return NOTIFY_OK;
@@ -346,16 +351,6 @@ void __init tick_nohz_init(void)
}
cpu_notifier(tick_nohz_cpu_down_callback, 0);
-
- /* Make sure full dynticks CPU are also RCU nocbs */
- for_each_cpu(cpu, nohz_full_mask) {
- if (!rcu_is_nocb_cpu(cpu)) {
- pr_warning("NO_HZ: CPU %d is not RCU nocb: "
- "cleared from nohz_full range", cpu);
- cpumask_clear_cpu(cpu, nohz_full_mask);
- }
- }
-
cpulist_scnprintf(nohz_full_buf, sizeof(nohz_full_buf), nohz_full_mask);
pr_info("NO_HZ: Full dynticks CPUs: %s.\n", nohz_full_buf);
}
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 846d0a1f235e..48b9fffabdc2 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -991,6 +991,14 @@ static int timekeeping_suspend(void)
read_persistent_clock(&timekeeping_suspend_time);
+ /*
+ * On some systems the persistent_clock can not be detected at
+ * timekeeping_init by its return value, so if we see a valid
+ * value returned, update the persistent_clock_exists flag.
+ */
+ if (timekeeping_suspend_time.tv_sec || timekeeping_suspend_time.tv_nsec)
+ persistent_clock_exist = true;
+
raw_spin_lock_irqsave(&timekeeper_lock, flags);
write_seqcount_begin(&timekeeper_seq);
timekeeping_forward_now(tk);
generated by cgit (git 2.34.1) at 2024-06-30 22:26:02 +0000