5 files changed, 37 insertions, 77 deletions

diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 50eb107..a9b76a4 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -97,20 +97,6 @@ EXPORT_SYMBOL_GPL(clockevent_delta2ns);
 static int __clockevents_switch_state(struct clock_event_device *dev,
 				      enum clock_event_state state)
 {
-	/* Transition with legacy set_mode() callback */
-	if (dev->set_mode) {
-		/* Legacy callback doesn't support new modes */
-		if (state > CLOCK_EVT_STATE_ONESHOT)
-			return -ENOSYS;
-		/*
-		 * 'clock_event_state' and 'clock_event_mode' have 1-to-1
-		 * mapping until *_ONESHOT, and so a simple cast will work.
-		 */
-		dev->set_mode((enum clock_event_mode)state, dev);
-		dev->mode = (enum clock_event_mode)state;
-		return 0;
-	}
-
 	if (dev->features & CLOCK_EVT_FEAT_DUMMY)
 		return 0;
 
@@ -204,12 +190,8 @@ int clockevents_tick_resume(struct clock_event_device *dev)
 {
 	int ret = 0;
 
-	if (dev->set_mode) {
-		dev->set_mode(CLOCK_EVT_MODE_RESUME, dev);
-		dev->mode = CLOCK_EVT_MODE_RESUME;
-	} else if (dev->tick_resume) {
+	if (dev->tick_resume)
 		ret = dev->tick_resume(dev);
-	}
 
 	return ret;
 }
@@ -460,26 +442,6 @@ int clockevents_unbind_device(struct clock_event_device *ced, int cpu)
 }
 EXPORT_SYMBOL_GPL(clockevents_unbind_device);
 
-/* Sanity check of state transition callbacks */
-static int clockevents_sanity_check(struct clock_event_device *dev)
-{
-	/* Legacy set_mode() callback */
-	if (dev->set_mode) {
-		/* We shouldn't be supporting new modes now */
-		WARN_ON(dev->set_state_periodic || dev->set_state_oneshot ||
-			dev->set_state_shutdown || dev->tick_resume ||
-			dev->set_state_oneshot_stopped);
-
-		BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED);
-		return 0;
-	}
-
-	if (dev->features & CLOCK_EVT_FEAT_DUMMY)
-		return 0;
-
-	return 0;
-}
-
 /**
  * clockevents_register_device - register a clock event device
  * @dev:	device to register
@@ -488,8 +450,6 @@ void clockevents_register_device(struct clock_event_device *dev)
 {
 	unsigned long flags;
 
-	BUG_ON(clockevents_sanity_check(dev));
-
 	/* Initialize state to DETACHED */
 	clockevent_set_state(dev, CLOCK_EVT_STATE_DETACHED);
 
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index d11c55b..4fcd99e 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -398,7 +398,6 @@ void tick_shutdown(unsigned int cpu)
 		 * the set mode function!
 		 */
 		clockevent_set_state(dev, CLOCK_EVT_STATE_DETACHED);
-		dev->mode = CLOCK_EVT_MODE_UNUSED;
 		clockevents_exchange_device(dev, NULL);
 		dev->event_handler = clockevents_handle_noop;
 		td->evtdev = NULL;
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 3319e16..7c7ec45 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -290,16 +290,17 @@ static int __init tick_nohz_full_setup(char *str)
 __setup("nohz_full=", tick_nohz_full_setup);
 
 static int tick_nohz_cpu_down_callback(struct notifier_block *nfb,
-						 unsigned long action,
-						 void *hcpu)
+				       unsigned long action,
+				       void *hcpu)
 {
 	unsigned int cpu = (unsigned long)hcpu;
 
 	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_DOWN_PREPARE:
 		/*
-		 * If we handle the timekeeping duty for full dynticks CPUs,
-		 * we can't safely shutdown that CPU.
+		 * The boot CPU handles housekeeping duty (unbound timers,
+		 * workqueues, timekeeping, ...) on behalf of full dynticks
+		 * CPUs. It must remain online when nohz full is enabled.
 		 */
 		if (tick_nohz_full_running && tick_do_timer_cpu == cpu)
 			return NOTIFY_BAD;
@@ -370,6 +371,12 @@ void __init tick_nohz_init(void)
 	cpu_notifier(tick_nohz_cpu_down_callback, 0);
 	pr_info("NO_HZ: Full dynticks CPUs: %*pbl.\n",
 		cpumask_pr_args(tick_nohz_full_mask));
+
+	/*
+	 * We need at least one CPU to handle housekeeping work such
+	 * as timekeeping, unbound timers, workqueues, ...
+	 */
+	WARN_ON_ONCE(cpumask_empty(housekeeping_mask));
 }
 #endif
 
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index f6ee2e6..3739ac6 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1614,7 +1614,7 @@ static __always_inline void timekeeping_freqadjust(struct timekeeper *tk,
 	negative = (tick_error < 0);
 
 	/* Sort out the magnitude of the correction */
-	tick_error = abs(tick_error);
+	tick_error = abs64(tick_error);
 	for (adj = 0; tick_error > interval; adj++)
 		tick_error >>= 1;
 
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index 129c960..f75e35b 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -225,7 +225,7 @@ print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu)
 		   (unsigned long long) dev->min_delta_ns);
 	SEQ_printf(m, " mult:           %u\n", dev->mult);
 	SEQ_printf(m, " shift:          %u\n", dev->shift);
-	SEQ_printf(m, " mode:           %d\n", dev->mode);
+	SEQ_printf(m, " mode:           %d\n", clockevent_get_state(dev));
 	SEQ_printf(m, " next_event:     %Ld nsecs\n",
 		   (unsigned long long) ktime_to_ns(dev->next_event));
 
@@ -233,40 +233,34 @@ print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu)
 	print_name_offset(m, dev->set_next_event);
 	SEQ_printf(m, "\n");
 
-	if (dev->set_mode) {
-		SEQ_printf(m, " set_mode:       ");
-		print_name_offset(m, dev->set_mode);
+	if (dev->set_state_shutdown) {
+		SEQ_printf(m, " shutdown: ");
+		print_name_offset(m, dev->set_state_shutdown);
 		SEQ_printf(m, "\n");
-	} else {
-		if (dev->set_state_shutdown) {
-			SEQ_printf(m, " shutdown: ");
-			print_name_offset(m, dev->set_state_shutdown);
-			SEQ_printf(m, "\n");
-		}
+	}
 
-		if (dev->set_state_periodic) {
-			SEQ_printf(m, " periodic: ");
-			print_name_offset(m, dev->set_state_periodic);
-			SEQ_printf(m, "\n");
-		}
+	if (dev->set_state_periodic) {
+		SEQ_printf(m, " periodic: ");
+		print_name_offset(m, dev->set_state_periodic);
+		SEQ_printf(m, "\n");
+	}
 
-		if (dev->set_state_oneshot) {
-			SEQ_printf(m, " oneshot:  ");
-			print_name_offset(m, dev->set_state_oneshot);
-			SEQ_printf(m, "\n");
-		}
+	if (dev->set_state_oneshot) {
+		SEQ_printf(m, " oneshot:  ");
+		print_name_offset(m, dev->set_state_oneshot);
+		SEQ_printf(m, "\n");
+	}
 
-		if (dev->set_state_oneshot_stopped) {
-			SEQ_printf(m, " oneshot stopped: ");
-			print_name_offset(m, dev->set_state_oneshot_stopped);
-			SEQ_printf(m, "\n");
-		}
+	if (dev->set_state_oneshot_stopped) {
+		SEQ_printf(m, " oneshot stopped: ");
+		print_name_offset(m, dev->set_state_oneshot_stopped);
+		SEQ_printf(m, "\n");
+	}
 
-		if (dev->tick_resume) {
-			SEQ_printf(m, " resume:   ");
-			print_name_offset(m, dev->tick_resume);
-			SEQ_printf(m, "\n");
-		}
+	if (dev->tick_resume) {
+		SEQ_printf(m, " resume:   ");
+		print_name_offset(m, dev->tick_resume);
+		SEQ_printf(m, "\n");
 	}
 
 	SEQ_printf(m, " event_handler:  ");