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-rw-r--r--kernel/locking/qspinlock.c2
-rw-r--r--kernel/sched/core.c36
-rw-r--r--kernel/time/clockevents.c42
-rw-r--r--kernel/time/tick-common.c1
-rw-r--r--kernel/time/tick-sched.c15
-rw-r--r--kernel/time/timekeeping.c2
-rw-r--r--kernel/time/timer_list.c54
7 files changed, 69 insertions, 83 deletions
diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c
index 337c8818541d..87e9ce6a63c5 100644
--- a/kernel/locking/qspinlock.c
+++ b/kernel/locking/qspinlock.c
@@ -289,7 +289,7 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
if (pv_enabled())
goto queue;
- if (virt_queued_spin_lock(lock))
+ if (virt_spin_lock(lock))
return;
/*
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 3595403921bd..97d276ff1edb 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -621,18 +621,21 @@ int get_nohz_timer_target(void)
int i, cpu = smp_processor_id();
struct sched_domain *sd;
- if (!idle_cpu(cpu))
+ if (!idle_cpu(cpu) && is_housekeeping_cpu(cpu))
return cpu;
rcu_read_lock();
for_each_domain(cpu, sd) {
for_each_cpu(i, sched_domain_span(sd)) {
- if (!idle_cpu(i)) {
+ if (!idle_cpu(i) && is_housekeeping_cpu(cpu)) {
cpu = i;
goto unlock;
}
}
}
+
+ if (!is_housekeeping_cpu(cpu))
+ cpu = housekeeping_any_cpu();
unlock:
rcu_read_unlock();
return cpu;
@@ -5178,24 +5181,47 @@ static void migrate_tasks(struct rq *dead_rq)
break;
/*
- * Ensure rq->lock covers the entire task selection
- * until the migration.
+ * pick_next_task assumes pinned rq->lock.
*/
lockdep_pin_lock(&rq->lock);
next = pick_next_task(rq, &fake_task);
BUG_ON(!next);
next->sched_class->put_prev_task(rq, next);
+ /*
+ * Rules for changing task_struct::cpus_allowed are holding
+ * both pi_lock and rq->lock, such that holding either
+ * stabilizes the mask.
+ *
+ * Drop rq->lock is not quite as disastrous as it usually is
+ * because !cpu_active at this point, which means load-balance
+ * will not interfere. Also, stop-machine.
+ */
+ lockdep_unpin_lock(&rq->lock);
+ raw_spin_unlock(&rq->lock);
+ raw_spin_lock(&next->pi_lock);
+ raw_spin_lock(&rq->lock);
+
+ /*
+ * Since we're inside stop-machine, _nothing_ should have
+ * changed the task, WARN if weird stuff happened, because in
+ * that case the above rq->lock drop is a fail too.
+ */
+ if (WARN_ON(task_rq(next) != rq || !task_on_rq_queued(next))) {
+ raw_spin_unlock(&next->pi_lock);
+ continue;
+ }
+
/* Find suitable destination for @next, with force if needed. */
dest_cpu = select_fallback_rq(dead_rq->cpu, next);
- lockdep_unpin_lock(&rq->lock);
rq = __migrate_task(rq, next, dest_cpu);
if (rq != dead_rq) {
raw_spin_unlock(&rq->lock);
rq = dead_rq;
raw_spin_lock(&rq->lock);
}
+ raw_spin_unlock(&next->pi_lock);
}
rq->stop = stop;
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 50eb107f1198..a9b76a40319e 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 d11c55b6ab7d..4fcd99e12aa0 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 3319e16f31e5..7c7ec4515983 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 f6ee2e6b6f5d..3739ac6aa473 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 129c96033e46..f75e35b60149 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: ");
generated by cgit v1.2.3-70-g09d2 (git 2.48.1) at 2025-02-23 09:24:23 +0000