diff options
Diffstat (limited to 'kernel/time/hrtimer.c')
-rw-r--r-- | kernel/time/hrtimer.c | 473 |
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); |