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-rw-r--r--kernel/time/hrtimer.c473
1 files changed, 199 insertions, 274 deletions
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 70625dff62ce..30899a8cc52c 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -58,6 +58,8 @@
#define HRTIMER_ACTIVE_SOFT (HRTIMER_ACTIVE_HARD << MASK_SHIFT)
#define HRTIMER_ACTIVE_ALL (HRTIMER_ACTIVE_SOFT | HRTIMER_ACTIVE_HARD)
+static void retrigger_next_event(void *arg);
+
/*
* The timer bases:
*
@@ -111,18 +113,17 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
.clockid = CLOCK_TAI,
.get_time = &ktime_get_clocktai,
},
- }
+ },
+ .csd = CSD_INIT(retrigger_next_event, NULL)
};
-static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
- /* Make sure we catch unsupported clockids */
- [0 ... MAX_CLOCKS - 1] = HRTIMER_MAX_CLOCK_BASES,
-
- [CLOCK_REALTIME] = HRTIMER_BASE_REALTIME,
- [CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC,
- [CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME,
- [CLOCK_TAI] = HRTIMER_BASE_TAI,
-};
+static inline bool hrtimer_base_is_online(struct hrtimer_cpu_base *base)
+{
+ if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))
+ return true;
+ else
+ return likely(base->online);
+}
/*
* Functions and macros which are different for UP/SMP systems are kept in a
@@ -145,11 +146,6 @@ static struct hrtimer_cpu_base migration_cpu_base = {
#define migration_base migration_cpu_base.clock_base[0]
-static inline bool is_migration_base(struct hrtimer_clock_base *base)
-{
- return base == &migration_base;
-}
-
/*
* We are using hashed locking: holding per_cpu(hrtimer_bases)[n].lock
* means that all timers which are tied to this base via timer->base are
@@ -183,27 +179,54 @@ struct hrtimer_clock_base *lock_hrtimer_base(const struct hrtimer *timer,
}
/*
- * We do not migrate the timer when it is expiring before the next
- * event on the target cpu. When high resolution is enabled, we cannot
- * reprogram the target cpu hardware and we would cause it to fire
- * late. To keep it simple, we handle the high resolution enabled and
- * disabled case similar.
+ * Check if the elected target is suitable considering its next
+ * event and the hotplug state of the current CPU.
+ *
+ * If the elected target is remote and its next event is after the timer
+ * to queue, then a remote reprogram is necessary. However there is no
+ * guarantee the IPI handling the operation would arrive in time to meet
+ * the high resolution deadline. In this case the local CPU becomes a
+ * preferred target, unless it is offline.
+ *
+ * High and low resolution modes are handled the same way for simplicity.
*
* Called with cpu_base->lock of target cpu held.
*/
-static int
-hrtimer_check_target(struct hrtimer *timer, struct hrtimer_clock_base *new_base)
+static bool hrtimer_suitable_target(struct hrtimer *timer, struct hrtimer_clock_base *new_base,
+ struct hrtimer_cpu_base *new_cpu_base,
+ struct hrtimer_cpu_base *this_cpu_base)
{
ktime_t expires;
+ /*
+ * The local CPU clockevent can be reprogrammed. Also get_target_base()
+ * guarantees it is online.
+ */
+ if (new_cpu_base == this_cpu_base)
+ return true;
+
+ /*
+ * The offline local CPU can't be the default target if the
+ * next remote target event is after this timer. Keep the
+ * elected new base. An IPI will we issued to reprogram
+ * it as a last resort.
+ */
+ if (!hrtimer_base_is_online(this_cpu_base))
+ return true;
+
expires = ktime_sub(hrtimer_get_expires(timer), new_base->offset);
- return expires < new_base->cpu_base->expires_next;
+
+ return expires >= new_base->cpu_base->expires_next;
}
-static inline
-struct hrtimer_cpu_base *get_target_base(struct hrtimer_cpu_base *base,
- int pinned)
+static inline struct hrtimer_cpu_base *get_target_base(struct hrtimer_cpu_base *base, int pinned)
{
+ if (!hrtimer_base_is_online(base)) {
+ int cpu = cpumask_any_and(cpu_online_mask, housekeeping_cpumask(HK_TYPE_TIMER));
+
+ return &per_cpu(hrtimer_bases, cpu);
+ }
+
#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
if (static_branch_likely(&timers_migration_enabled) && !pinned)
return &per_cpu(hrtimer_bases, get_nohz_timer_target());
@@ -254,8 +277,8 @@ again:
raw_spin_unlock(&base->cpu_base->lock);
raw_spin_lock(&new_base->cpu_base->lock);
- if (new_cpu_base != this_cpu_base &&
- hrtimer_check_target(timer, new_base)) {
+ if (!hrtimer_suitable_target(timer, new_base, new_cpu_base,
+ this_cpu_base)) {
raw_spin_unlock(&new_base->cpu_base->lock);
raw_spin_lock(&base->cpu_base->lock);
new_cpu_base = this_cpu_base;
@@ -264,8 +287,7 @@ again:
}
WRITE_ONCE(timer->base, new_base);
} else {
- if (new_cpu_base != this_cpu_base &&
- hrtimer_check_target(timer, new_base)) {
+ if (!hrtimer_suitable_target(timer, new_base, new_cpu_base, this_cpu_base)) {
new_cpu_base = this_cpu_base;
goto again;
}
@@ -275,11 +297,6 @@ again:
#else /* CONFIG_SMP */
-static inline bool is_migration_base(struct hrtimer_clock_base *base)
-{
- return false;
-}
-
static inline struct hrtimer_clock_base *
lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
__acquires(&timer->base->cpu_base->lock)
@@ -349,7 +366,7 @@ static const struct debug_obj_descr hrtimer_debug_descr;
static void *hrtimer_debug_hint(void *addr)
{
- return ((struct hrtimer *) addr)->function;
+ return ACCESS_PRIVATE((struct hrtimer *)addr, function);
}
/*
@@ -417,6 +434,11 @@ static inline void debug_hrtimer_init(struct hrtimer *timer)
debug_object_init(timer, &hrtimer_debug_descr);
}
+static inline void debug_hrtimer_init_on_stack(struct hrtimer *timer)
+{
+ debug_object_init_on_stack(timer, &hrtimer_debug_descr);
+}
+
static inline void debug_hrtimer_activate(struct hrtimer *timer,
enum hrtimer_mode mode)
{
@@ -428,28 +450,6 @@ static inline void debug_hrtimer_deactivate(struct hrtimer *timer)
debug_object_deactivate(timer, &hrtimer_debug_descr);
}
-static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
- enum hrtimer_mode mode);
-
-void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
- enum hrtimer_mode mode)
-{
- debug_object_init_on_stack(timer, &hrtimer_debug_descr);
- __hrtimer_init(timer, clock_id, mode);
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
-
-static void __hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
- clockid_t clock_id, enum hrtimer_mode mode);
-
-void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
- clockid_t clock_id, enum hrtimer_mode mode)
-{
- debug_object_init_on_stack(&sl->timer, &hrtimer_debug_descr);
- __hrtimer_init_sleeper(sl, clock_id, mode);
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_sleeper_on_stack);
-
void destroy_hrtimer_on_stack(struct hrtimer *timer)
{
debug_object_free(timer, &hrtimer_debug_descr);
@@ -459,17 +459,23 @@ EXPORT_SYMBOL_GPL(destroy_hrtimer_on_stack);
#else
static inline void debug_hrtimer_init(struct hrtimer *timer) { }
+static inline void debug_hrtimer_init_on_stack(struct hrtimer *timer) { }
static inline void debug_hrtimer_activate(struct hrtimer *timer,
enum hrtimer_mode mode) { }
static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }
#endif
-static inline void
-debug_init(struct hrtimer *timer, clockid_t clockid,
- enum hrtimer_mode mode)
+static inline void debug_setup(struct hrtimer *timer, clockid_t clockid, enum hrtimer_mode mode)
{
debug_hrtimer_init(timer);
- trace_hrtimer_init(timer, clockid, mode);
+ trace_hrtimer_setup(timer, clockid, mode);
+}
+
+static inline void debug_setup_on_stack(struct hrtimer *timer, clockid_t clockid,
+ enum hrtimer_mode mode)
+{
+ debug_hrtimer_init_on_stack(timer);
+ trace_hrtimer_setup(timer, clockid, mode);
}
static inline void debug_activate(struct hrtimer *timer,
@@ -644,17 +650,12 @@ static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
/*
* Is the high resolution mode active ?
*/
-static inline int __hrtimer_hres_active(struct hrtimer_cpu_base *cpu_base)
+static inline int hrtimer_hres_active(struct hrtimer_cpu_base *cpu_base)
{
return IS_ENABLED(CONFIG_HIGH_RES_TIMERS) ?
cpu_base->hres_active : 0;
}
-static inline int hrtimer_hres_active(void)
-{
- return __hrtimer_hres_active(this_cpu_ptr(&hrtimer_bases));
-}
-
static void __hrtimer_reprogram(struct hrtimer_cpu_base *cpu_base,
struct hrtimer *next_timer,
ktime_t expires_next)
@@ -678,7 +679,7 @@ static void __hrtimer_reprogram(struct hrtimer_cpu_base *cpu_base,
* set. So we'd effectively block all timers until the T2 event
* fires.
*/
- if (!__hrtimer_hres_active(cpu_base) || cpu_base->hang_detected)
+ if (!hrtimer_hres_active(cpu_base) || cpu_base->hang_detected)
return;
tick_program_event(expires_next, 1);
@@ -730,8 +731,6 @@ static inline int hrtimer_is_hres_enabled(void)
return hrtimer_hres_enabled;
}
-static void retrigger_next_event(void *arg);
-
/*
* Switch to high resolution mode
*/
@@ -789,12 +788,12 @@ static void retrigger_next_event(void *arg)
* function call will take care of the reprogramming in case the
* CPU was in a NOHZ idle sleep.
*/
- if (!__hrtimer_hres_active(base) && !tick_nohz_active)
+ if (!hrtimer_hres_active(base) && !tick_nohz_active)
return;
raw_spin_lock(&base->lock);
hrtimer_update_base(base);
- if (__hrtimer_hres_active(base))
+ if (hrtimer_hres_active(base))
hrtimer_force_reprogram(base, 0);
else
hrtimer_update_next_event(base);
@@ -951,7 +950,7 @@ void clock_was_set(unsigned int bases)
cpumask_var_t mask;
int cpu;
- if (!__hrtimer_hres_active(cpu_base) && !tick_nohz_active)
+ if (!hrtimer_hres_active(cpu_base) && !tick_nohz_active)
goto out_timerfd;
if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
@@ -1081,11 +1080,10 @@ EXPORT_SYMBOL_GPL(hrtimer_forward);
* The timer is inserted in expiry order. Insertion into the
* red black tree is O(log(n)). Must hold the base lock.
*
- * Returns 1 when the new timer is the leftmost timer in the tree.
+ * Returns true when the new timer is the leftmost timer in the tree.
*/
-static int enqueue_hrtimer(struct hrtimer *timer,
- struct hrtimer_clock_base *base,
- enum hrtimer_mode mode)
+static bool enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base,
+ enum hrtimer_mode mode)
{
debug_activate(timer, mode);
WARN_ON_ONCE(!base->cpu_base->online);
@@ -1182,7 +1180,7 @@ static inline ktime_t hrtimer_update_lowres(struct hrtimer *timer, ktime_t tim,
/*
* CONFIG_TIME_LOW_RES indicates that the system has no way to return
* granular time values. For relative timers we add hrtimer_resolution
- * (i.e. one jiffie) to prevent short timeouts.
+ * (i.e. one jiffy) to prevent short timeouts.
*/
timer->is_rel = mode & HRTIMER_MODE_REL;
if (timer->is_rel)
@@ -1220,6 +1218,7 @@ static int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
u64 delta_ns, const enum hrtimer_mode mode,
struct hrtimer_clock_base *base)
{
+ struct hrtimer_cpu_base *this_cpu_base = this_cpu_ptr(&hrtimer_bases);
struct hrtimer_clock_base *new_base;
bool force_local, first;
@@ -1231,10 +1230,16 @@ static int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
* and enforce reprogramming after it is queued no matter whether
* it is the new first expiring timer again or not.
*/
- force_local = base->cpu_base == this_cpu_ptr(&hrtimer_bases);
+ force_local = base->cpu_base == this_cpu_base;
force_local &= base->cpu_base->next_timer == timer;
/*
+ * Don't force local queuing if this enqueue happens on a unplugged
+ * CPU after hrtimer_cpu_dying() has been invoked.
+ */
+ force_local &= this_cpu_base->online;
+
+ /*
* Remove an active timer from the queue. In case it is not queued
* on the current CPU, make sure that remove_hrtimer() updates the
* remote data correctly.
@@ -1263,8 +1268,27 @@ static int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
}
first = enqueue_hrtimer(timer, new_base, mode);
- if (!force_local)
- return first;
+ if (!force_local) {
+ /*
+ * If the current CPU base is online, then the timer is
+ * never queued on a remote CPU if it would be the first
+ * expiring timer there.
+ */
+ if (hrtimer_base_is_online(this_cpu_base))
+ return first;
+
+ /*
+ * Timer was enqueued remote because the current base is
+ * already offline. If the timer is the first to expire,
+ * kick the remote CPU to reprogram the clock event.
+ */
+ if (first) {
+ struct hrtimer_cpu_base *new_cpu_base = new_base->cpu_base;
+
+ smp_call_function_single_async(new_cpu_base->cpu, &new_cpu_base->csd);
+ }
+ return 0;
+ }
/*
* Timer was forced to stay on the current CPU to avoid
@@ -1354,11 +1378,13 @@ static void hrtimer_cpu_base_init_expiry_lock(struct hrtimer_cpu_base *base)
}
static void hrtimer_cpu_base_lock_expiry(struct hrtimer_cpu_base *base)
+ __acquires(&base->softirq_expiry_lock)
{
spin_lock(&base->softirq_expiry_lock);
}
static void hrtimer_cpu_base_unlock_expiry(struct hrtimer_cpu_base *base)
+ __releases(&base->softirq_expiry_lock)
{
spin_unlock(&base->softirq_expiry_lock);
}
@@ -1381,13 +1407,25 @@ static void hrtimer_sync_wait_running(struct hrtimer_cpu_base *cpu_base,
}
}
+#ifdef CONFIG_SMP
+static __always_inline bool is_migration_base(struct hrtimer_clock_base *base)
+{
+ return base == &migration_base;
+}
+#else
+static __always_inline bool is_migration_base(struct hrtimer_clock_base *base)
+{
+ return false;
+}
+#endif
+
/*
* This function is called on PREEMPT_RT kernels when the fast path
* deletion of a timer failed because the timer callback function was
* running.
*
* This prevents priority inversion: if the soft irq thread is preempted
- * in the middle of a timer callback, then calling del_timer_sync() can
+ * in the middle of a timer callback, then calling hrtimer_cancel() can
* lead to two issues:
*
* - If the caller is on a remote CPU then it has to spin wait for the timer
@@ -1491,7 +1529,7 @@ u64 hrtimer_get_next_event(void)
raw_spin_lock_irqsave(&cpu_base->lock, flags);
- if (!__hrtimer_hres_active(cpu_base))
+ if (!hrtimer_hres_active(cpu_base))
expires = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL);
raw_spin_unlock_irqrestore(&cpu_base->lock, flags);
@@ -1514,7 +1552,7 @@ u64 hrtimer_next_event_without(const struct hrtimer *exclude)
raw_spin_lock_irqsave(&cpu_base->lock, flags);
- if (__hrtimer_hres_active(cpu_base)) {
+ if (hrtimer_hres_active(cpu_base)) {
unsigned int active;
if (!cpu_base->softirq_activated) {
@@ -1535,18 +1573,24 @@ u64 hrtimer_next_event_without(const struct hrtimer *exclude)
static inline int hrtimer_clockid_to_base(clockid_t clock_id)
{
- if (likely(clock_id < MAX_CLOCKS)) {
- int base = hrtimer_clock_to_base_table[clock_id];
-
- if (likely(base != HRTIMER_MAX_CLOCK_BASES))
- return base;
+ switch (clock_id) {
+ case CLOCK_REALTIME:
+ return HRTIMER_BASE_REALTIME;
+ case CLOCK_MONOTONIC:
+ return HRTIMER_BASE_MONOTONIC;
+ case CLOCK_BOOTTIME:
+ return HRTIMER_BASE_BOOTTIME;
+ case CLOCK_TAI:
+ return HRTIMER_BASE_TAI;
+ default:
+ WARN(1, "Invalid clockid %d. Using MONOTONIC\n", clock_id);
+ return HRTIMER_BASE_MONOTONIC;
}
- WARN(1, "Invalid clockid %d. Using MONOTONIC\n", clock_id);
- return HRTIMER_BASE_MONOTONIC;
}
-static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
- enum hrtimer_mode mode)
+static void __hrtimer_setup(struct hrtimer *timer,
+ enum hrtimer_restart (*function)(struct hrtimer *),
+ clockid_t clock_id, enum hrtimer_mode mode)
{
bool softtimer = !!(mode & HRTIMER_MODE_SOFT);
struct hrtimer_cpu_base *cpu_base;
@@ -1579,11 +1623,17 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
timer->is_hard = !!(mode & HRTIMER_MODE_HARD);
timer->base = &cpu_base->clock_base[base];
timerqueue_init(&timer->node);
+
+ if (WARN_ON_ONCE(!function))
+ ACCESS_PRIVATE(timer, function) = hrtimer_dummy_timeout;
+ else
+ ACCESS_PRIVATE(timer, function) = function;
}
/**
- * hrtimer_init - initialize a timer to the given clock
+ * hrtimer_setup - initialize a timer to the given clock
* @timer: the timer to be initialized
+ * @function: the callback function
* @clock_id: the clock to be used
* @mode: The modes which are relevant for initialization:
* HRTIMER_MODE_ABS, HRTIMER_MODE_REL, HRTIMER_MODE_ABS_SOFT,
@@ -1593,13 +1643,32 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
* but the PINNED bit is ignored as pinning happens
* when the hrtimer is started
*/
-void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
- enum hrtimer_mode mode)
+void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function)(struct hrtimer *),
+ clockid_t clock_id, enum hrtimer_mode mode)
+{
+ debug_setup(timer, clock_id, mode);
+ __hrtimer_setup(timer, function, clock_id, mode);
+}
+EXPORT_SYMBOL_GPL(hrtimer_setup);
+
+/**
+ * hrtimer_setup_on_stack - initialize a timer on stack memory
+ * @timer: The timer to be initialized
+ * @function: the callback function
+ * @clock_id: The clock to be used
+ * @mode: The timer mode
+ *
+ * Similar to hrtimer_setup(), except that this one must be used if struct hrtimer is in stack
+ * memory.
+ */
+void hrtimer_setup_on_stack(struct hrtimer *timer,
+ enum hrtimer_restart (*function)(struct hrtimer *),
+ clockid_t clock_id, enum hrtimer_mode mode)
{
- debug_init(timer, clock_id, mode);
- __hrtimer_init(timer, clock_id, mode);
+ debug_setup_on_stack(timer, clock_id, mode);
+ __hrtimer_setup(timer, function, clock_id, mode);
}
-EXPORT_SYMBOL_GPL(hrtimer_init);
+EXPORT_SYMBOL_GPL(hrtimer_setup_on_stack);
/*
* A timer is active, when it is enqueued into the rbtree or the
@@ -1670,7 +1739,7 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base,
raw_write_seqcount_barrier(&base->seq);
__remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 0);
- fn = timer->function;
+ fn = ACCESS_PRIVATE(timer, function);
/*
* Clear the 'is relative' flag for the TIME_LOW_RES case. If the
@@ -1760,7 +1829,7 @@ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now,
}
}
-static __latent_entropy void hrtimer_run_softirq(struct softirq_action *h)
+static __latent_entropy void hrtimer_run_softirq(void)
{
struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
unsigned long flags;
@@ -1812,7 +1881,7 @@ retry:
if (!ktime_before(now, cpu_base->softirq_expires_next)) {
cpu_base->softirq_expires_next = KTIME_MAX;
cpu_base->softirq_activated = 1;
- raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+ raise_timer_softirq(HRTIMER_SOFTIRQ);
}
__hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_HARD);
@@ -1875,25 +1944,7 @@ retry:
tick_program_event(expires_next, 1);
pr_warn_once("hrtimer: interrupt took %llu ns\n", ktime_to_ns(delta));
}
-
-/* called with interrupts disabled */
-static inline void __hrtimer_peek_ahead_timers(void)
-{
- struct tick_device *td;
-
- if (!hrtimer_hres_active())
- return;
-
- td = this_cpu_ptr(&tick_cpu_device);
- if (td && td->evtdev)
- hrtimer_interrupt(td->evtdev);
-}
-
-#else /* CONFIG_HIGH_RES_TIMERS */
-
-static inline void __hrtimer_peek_ahead_timers(void) { }
-
-#endif /* !CONFIG_HIGH_RES_TIMERS */
+#endif /* !CONFIG_HIGH_RES_TIMERS */
/*
* Called from run_local_timers in hardirq context every jiffy
@@ -1904,7 +1955,7 @@ void hrtimer_run_queues(void)
unsigned long flags;
ktime_t now;
- if (__hrtimer_hres_active(cpu_base))
+ if (hrtimer_hres_active(cpu_base))
return;
/*
@@ -1925,7 +1976,7 @@ void hrtimer_run_queues(void)
if (!ktime_before(now, cpu_base->softirq_expires_next)) {
cpu_base->softirq_expires_next = KTIME_MAX;
cpu_base->softirq_activated = 1;
- raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+ raise_timer_softirq(HRTIMER_SOFTIRQ);
}
__hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_HARD);
@@ -1963,7 +2014,7 @@ void hrtimer_sleeper_start_expires(struct hrtimer_sleeper *sl,
* Make the enqueue delivery mode check work on RT. If the sleeper
* was initialized for hard interrupt delivery, force the mode bit.
* This is a special case for hrtimer_sleepers because
- * hrtimer_init_sleeper() determines the delivery mode on RT so the
+ * __hrtimer_setup_sleeper() determines the delivery mode on RT so the
* fiddling with this decision is avoided at the call sites.
*/
if (IS_ENABLED(CONFIG_PREEMPT_RT) && sl->timer.is_hard)
@@ -1973,8 +2024,8 @@ void hrtimer_sleeper_start_expires(struct hrtimer_sleeper *sl,
}
EXPORT_SYMBOL_GPL(hrtimer_sleeper_start_expires);
-static void __hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
- clockid_t clock_id, enum hrtimer_mode mode)
+static void __hrtimer_setup_sleeper(struct hrtimer_sleeper *sl,
+ clockid_t clock_id, enum hrtimer_mode mode)
{
/*
* On PREEMPT_RT enabled kernels hrtimers which are not explicitly
@@ -1996,29 +2047,27 @@ static void __hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
* expiry.
*/
if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
- if (task_is_realtime(current) && !(mode & HRTIMER_MODE_SOFT))
+ if (rt_or_dl_task_policy(current) && !(mode & HRTIMER_MODE_SOFT))
mode |= HRTIMER_MODE_HARD;
}
- __hrtimer_init(&sl->timer, clock_id, mode);
- sl->timer.function = hrtimer_wakeup;
+ __hrtimer_setup(&sl->timer, hrtimer_wakeup, clock_id, mode);
sl->task = current;
}
/**
- * hrtimer_init_sleeper - initialize sleeper to the given clock
+ * hrtimer_setup_sleeper_on_stack - initialize a sleeper in stack memory
* @sl: sleeper to be initialized
* @clock_id: the clock to be used
* @mode: timer mode abs/rel
*/
-void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, clockid_t clock_id,
- enum hrtimer_mode mode)
+void hrtimer_setup_sleeper_on_stack(struct hrtimer_sleeper *sl,
+ clockid_t clock_id, enum hrtimer_mode mode)
{
- debug_init(&sl->timer, clock_id, mode);
- __hrtimer_init_sleeper(sl, clock_id, mode);
-
+ debug_setup_on_stack(&sl->timer, clock_id, mode);
+ __hrtimer_setup_sleeper(sl, clock_id, mode);
}
-EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
+EXPORT_SYMBOL_GPL(hrtimer_setup_sleeper_on_stack);
int nanosleep_copyout(struct restart_block *restart, struct timespec64 *ts)
{
@@ -2079,8 +2128,7 @@ static long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
struct hrtimer_sleeper t;
int ret;
- hrtimer_init_sleeper_on_stack(&t, restart->nanosleep.clockid,
- HRTIMER_MODE_ABS);
+ hrtimer_setup_sleeper_on_stack(&t, restart->nanosleep.clockid, HRTIMER_MODE_ABS);
hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
ret = do_nanosleep(&t, HRTIMER_MODE_ABS);
destroy_hrtimer_on_stack(&t.timer);
@@ -2093,14 +2141,9 @@ long hrtimer_nanosleep(ktime_t rqtp, const enum hrtimer_mode mode,
struct restart_block *restart;
struct hrtimer_sleeper t;
int ret = 0;
- u64 slack;
- slack = current->timer_slack_ns;
- if (rt_task(current))
- slack = 0;
-
- hrtimer_init_sleeper_on_stack(&t, clockid, mode);
- hrtimer_set_expires_range_ns(&t.timer, rqtp, slack);
+ hrtimer_setup_sleeper_on_stack(&t, clockid, mode);
+ hrtimer_set_expires_range_ns(&t.timer, rqtp, current->timer_slack_ns);
ret = do_nanosleep(&t, mode);
if (ret != -ERESTART_RESTARTBLOCK)
goto out;
@@ -2180,6 +2223,15 @@ int hrtimers_prepare_cpu(unsigned int cpu)
}
cpu_base->cpu = cpu;
+ hrtimer_cpu_base_init_expiry_lock(cpu_base);
+ return 0;
+}
+
+int hrtimers_cpu_starting(unsigned int cpu)
+{
+ struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
+
+ /* Clear out any left over state from a CPU down operation */
cpu_base->active_bases = 0;
cpu_base->hres_active = 0;
cpu_base->hang_detected = 0;
@@ -2188,7 +2240,6 @@ int hrtimers_prepare_cpu(unsigned int cpu)
cpu_base->expires_next = KTIME_MAX;
cpu_base->softirq_expires_next = KTIME_MAX;
cpu_base->online = 1;
- hrtimer_cpu_base_init_expiry_lock(cpu_base);
return 0;
}
@@ -2264,132 +2315,6 @@ int hrtimers_cpu_dying(unsigned int dying_cpu)
void __init hrtimers_init(void)
{
hrtimers_prepare_cpu(smp_processor_id());
+ hrtimers_cpu_starting(smp_processor_id());
open_softirq(HRTIMER_SOFTIRQ, hrtimer_run_softirq);
}
-
-/**
- * schedule_hrtimeout_range_clock - sleep until timeout
- * @expires: timeout value (ktime_t)
- * @delta: slack in expires timeout (ktime_t) for SCHED_OTHER tasks
- * @mode: timer mode
- * @clock_id: timer clock to be used
- */
-int __sched
-schedule_hrtimeout_range_clock(ktime_t *expires, u64 delta,
- const enum hrtimer_mode mode, clockid_t clock_id)
-{
- 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 == 0) {
- __set_current_state(TASK_RUNNING);
- return 0;
- }
-
- /*
- * A NULL parameter means "infinite"
- */
- if (!expires) {
- schedule();
- return -EINTR;
- }
-
- /*
- * Override any slack passed by the user if under
- * rt contraints.
- */
- if (rt_task(current))
- delta = 0;
-
- hrtimer_init_sleeper_on_stack(&t, clock_id, mode);
- hrtimer_set_expires_range_ns(&t.timer, *expires, delta);
- hrtimer_sleeper_start_expires(&t, mode);
-
- 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_clock);
-
-/**
- * schedule_hrtimeout_range - sleep until timeout
- * @expires: timeout value (ktime_t)
- * @delta: slack in expires timeout (ktime_t) for SCHED_OTHER tasks
- * @mode: timer mode
- *
- * 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
- * for regular (non RT/DL) tasks.
- * 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 unless the current task is explicitly
- * woken up, (e.g. by wake_up_process()).
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task or the current task is explicitly woken
- * up.
- *
- * The current task state is guaranteed to be TASK_RUNNING when this
- * routine returns.
- *
- * Returns 0 when the timer has expired. If the task was woken before the
- * timer expired by a signal (only possible in state TASK_INTERRUPTIBLE) or
- * by an explicit wakeup, it returns -EINTR.
- */
-int __sched schedule_hrtimeout_range(ktime_t *expires, u64 delta,
- const enum hrtimer_mode mode)
-{
- return schedule_hrtimeout_range_clock(expires, delta, mode,
- CLOCK_MONOTONIC);
-}
-EXPORT_SYMBOL_GPL(schedule_hrtimeout_range);
-
-/**
- * schedule_hrtimeout - sleep until timeout
- * @expires: timeout value (ktime_t)
- * @mode: timer mode
- *
- * 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 unless the current task is explicitly
- * woken up, (e.g. by wake_up_process()).
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task or the current task is explicitly woken
- * up.
- *
- * The current task state is guaranteed to be TASK_RUNNING when this
- * routine returns.
- *
- * Returns 0 when the timer has expired. If the task was woken before the
- * timer expired by a signal (only possible in state TASK_INTERRUPTIBLE) or
- * by an explicit wakeup, it returns -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);