diff options
Diffstat (limited to 'kernel/locking')
| -rw-r--r-- | kernel/locking/lockdep.c | 23 | ||||
| -rw-r--r-- | kernel/locking/mutex.c | 18 | ||||
| -rw-r--r-- | kernel/locking/percpu-rwsem.c | 5 | ||||
| -rw-r--r-- | kernel/locking/qrwlock.c | 17 | ||||
| -rw-r--r-- | kernel/locking/qspinlock.c | 5 | ||||
| -rw-r--r-- | kernel/locking/rtmutex.c | 11 | ||||
| -rw-r--r-- | kernel/locking/rwbase_rt.c | 7 | ||||
| -rw-r--r-- | kernel/locking/rwsem.c | 130 | ||||
| -rw-r--r-- | kernel/locking/semaphore.c | 15 |
9 files changed, 158 insertions, 73 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index a4382ae1be59..81e87280513e 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -60,7 +60,6 @@ #include "lockdep_internals.h" -#define CREATE_TRACE_POINTS #include <trace/events/lock.h> #ifdef CONFIG_PROVE_LOCKING @@ -1411,7 +1410,7 @@ static struct lock_list *alloc_list_entry(void) */ static int add_lock_to_list(struct lock_class *this, struct lock_class *links_to, struct list_head *head, - unsigned long ip, u16 distance, u8 dep, + u16 distance, u8 dep, const struct lock_trace *trace) { struct lock_list *entry; @@ -3164,19 +3163,15 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev, * to the previous lock's dependency list: */ ret = add_lock_to_list(hlock_class(next), hlock_class(prev), - &hlock_class(prev)->locks_after, - next->acquire_ip, distance, - calc_dep(prev, next), - *trace); + &hlock_class(prev)->locks_after, distance, + calc_dep(prev, next), *trace); if (!ret) return 0; ret = add_lock_to_list(hlock_class(prev), hlock_class(next), - &hlock_class(next)->locks_before, - next->acquire_ip, distance, - calc_depb(prev, next), - *trace); + &hlock_class(next)->locks_before, distance, + calc_depb(prev, next), *trace); if (!ret) return 0; @@ -4267,14 +4262,13 @@ static void __trace_hardirqs_on_caller(void) /** * lockdep_hardirqs_on_prepare - Prepare for enabling interrupts - * @ip: Caller address * * Invoked before a possible transition to RCU idle from exit to user or * guest mode. This ensures that all RCU operations are done before RCU * stops watching. After the RCU transition lockdep_hardirqs_on() has to be * invoked to set the final state. */ -void lockdep_hardirqs_on_prepare(unsigned long ip) +void lockdep_hardirqs_on_prepare(void) { if (unlikely(!debug_locks)) return; @@ -4871,8 +4865,7 @@ EXPORT_SYMBOL_GPL(__lockdep_no_validate__); static void print_lock_nested_lock_not_held(struct task_struct *curr, - struct held_lock *hlock, - unsigned long ip) + struct held_lock *hlock) { if (!debug_locks_off()) return; @@ -5048,7 +5041,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, chain_key = iterate_chain_key(chain_key, hlock_id(hlock)); if (nest_lock && !__lock_is_held(nest_lock, -1)) { - print_lock_nested_lock_not_held(curr, hlock, ip); + print_lock_nested_lock_not_held(curr, hlock); return 0; } diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 5e3585950ec8..d973fe6041bf 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -30,6 +30,9 @@ #include <linux/debug_locks.h> #include <linux/osq_lock.h> +#define CREATE_TRACE_POINTS +#include <trace/events/lock.h> + #ifndef CONFIG_PREEMPT_RT #include "mutex.h" @@ -599,12 +602,14 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas preempt_disable(); mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip); + trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN); if (__mutex_trylock(lock) || mutex_optimistic_spin(lock, ww_ctx, NULL)) { /* got the lock, yay! */ lock_acquired(&lock->dep_map, ip); if (ww_ctx) ww_mutex_set_context_fastpath(ww, ww_ctx); + trace_contention_end(lock, 0); preempt_enable(); return 0; } @@ -641,6 +646,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas } set_current_state(state); + trace_contention_begin(lock, LCB_F_MUTEX); for (;;) { bool first; @@ -680,10 +686,16 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas * state back to RUNNING and fall through the next schedule(), * or we must see its unlock and acquire. */ - if (__mutex_trylock_or_handoff(lock, first) || - (first && mutex_optimistic_spin(lock, ww_ctx, &waiter))) + if (__mutex_trylock_or_handoff(lock, first)) break; + if (first) { + trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN); + if (mutex_optimistic_spin(lock, ww_ctx, &waiter)) + break; + trace_contention_begin(lock, LCB_F_MUTEX); + } + raw_spin_lock(&lock->wait_lock); } raw_spin_lock(&lock->wait_lock); @@ -707,6 +719,7 @@ acquired: skip_wait: /* got the lock - cleanup and rejoice! */ lock_acquired(&lock->dep_map, ip); + trace_contention_end(lock, 0); if (ww_ctx) ww_mutex_lock_acquired(ww, ww_ctx); @@ -719,6 +732,7 @@ err: __set_current_state(TASK_RUNNING); __mutex_remove_waiter(lock, &waiter); err_early_kill: + trace_contention_end(lock, ret); raw_spin_unlock(&lock->wait_lock); debug_mutex_free_waiter(&waiter); mutex_release(&lock->dep_map, ip); diff --git a/kernel/locking/percpu-rwsem.c b/kernel/locking/percpu-rwsem.c index c9fdae94e098..5fe4c5495ba3 100644 --- a/kernel/locking/percpu-rwsem.c +++ b/kernel/locking/percpu-rwsem.c @@ -9,6 +9,7 @@ #include <linux/sched/task.h> #include <linux/sched/debug.h> #include <linux/errno.h> +#include <trace/events/lock.h> int __percpu_init_rwsem(struct percpu_rw_semaphore *sem, const char *name, struct lock_class_key *key) @@ -171,9 +172,11 @@ bool __sched __percpu_down_read(struct percpu_rw_semaphore *sem, bool try) if (try) return false; + trace_contention_begin(sem, LCB_F_PERCPU | LCB_F_READ); preempt_enable(); percpu_rwsem_wait(sem, /* .reader = */ true); preempt_disable(); + trace_contention_end(sem, 0); return true; } @@ -216,6 +219,7 @@ void __sched percpu_down_write(struct percpu_rw_semaphore *sem) { might_sleep(); rwsem_acquire(&sem->dep_map, 0, 0, _RET_IP_); + trace_contention_begin(sem, LCB_F_PERCPU | LCB_F_WRITE); /* Notify readers to take the slow path. */ rcu_sync_enter(&sem->rss); @@ -237,6 +241,7 @@ void __sched percpu_down_write(struct percpu_rw_semaphore *sem) /* Wait for all active readers to complete. */ rcuwait_wait_event(&sem->writer, readers_active_check(sem), TASK_UNINTERRUPTIBLE); + trace_contention_end(sem, 0); } EXPORT_SYMBOL_GPL(percpu_down_write); diff --git a/kernel/locking/qrwlock.c b/kernel/locking/qrwlock.c index ec36b73f4733..2e1600906c9f 100644 --- a/kernel/locking/qrwlock.c +++ b/kernel/locking/qrwlock.c @@ -12,10 +12,11 @@ #include <linux/percpu.h> #include <linux/hardirq.h> #include <linux/spinlock.h> +#include <trace/events/lock.h> /** - * queued_read_lock_slowpath - acquire read lock of a queue rwlock - * @lock: Pointer to queue rwlock structure + * queued_read_lock_slowpath - acquire read lock of a queued rwlock + * @lock: Pointer to queued rwlock structure */ void queued_read_lock_slowpath(struct qrwlock *lock) { @@ -34,6 +35,8 @@ void queued_read_lock_slowpath(struct qrwlock *lock) } atomic_sub(_QR_BIAS, &lock->cnts); + trace_contention_begin(lock, LCB_F_SPIN | LCB_F_READ); + /* * Put the reader into the wait queue */ @@ -51,17 +54,21 @@ void queued_read_lock_slowpath(struct qrwlock *lock) * Signal the next one in queue to become queue head */ arch_spin_unlock(&lock->wait_lock); + + trace_contention_end(lock, 0); } EXPORT_SYMBOL(queued_read_lock_slowpath); /** - * queued_write_lock_slowpath - acquire write lock of a queue rwlock - * @lock : Pointer to queue rwlock structure + * queued_write_lock_slowpath - acquire write lock of a queued rwlock + * @lock : Pointer to queued rwlock structure */ void queued_write_lock_slowpath(struct qrwlock *lock) { int cnts; + trace_contention_begin(lock, LCB_F_SPIN | LCB_F_WRITE); + /* Put the writer into the wait queue */ arch_spin_lock(&lock->wait_lock); @@ -79,5 +86,7 @@ void queued_write_lock_slowpath(struct qrwlock *lock) } while (!atomic_try_cmpxchg_acquire(&lock->cnts, &cnts, _QW_LOCKED)); unlock: arch_spin_unlock(&lock->wait_lock); + + trace_contention_end(lock, 0); } EXPORT_SYMBOL(queued_write_lock_slowpath); diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c index cbff6ba53d56..65a9a10caa6f 100644 --- a/kernel/locking/qspinlock.c +++ b/kernel/locking/qspinlock.c @@ -22,6 +22,7 @@ #include <linux/prefetch.h> #include <asm/byteorder.h> #include <asm/qspinlock.h> +#include <trace/events/lock.h> /* * Include queued spinlock statistics code @@ -401,6 +402,8 @@ pv_queue: idx = node->count++; tail = encode_tail(smp_processor_id(), idx); + trace_contention_begin(lock, LCB_F_SPIN); + /* * 4 nodes are allocated based on the assumption that there will * not be nested NMIs taking spinlocks. That may not be true in @@ -554,6 +557,8 @@ locked: pv_kick_node(lock, next); release: + trace_contention_end(lock, 0); + /* * release the node */ diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 8555c4efe97c..7779ee8abc2a 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -24,6 +24,8 @@ #include <linux/sched/wake_q.h> #include <linux/ww_mutex.h> +#include <trace/events/lock.h> + #include "rtmutex_common.h" #ifndef WW_RT @@ -1579,6 +1581,8 @@ static int __sched __rt_mutex_slowlock(struct rt_mutex_base *lock, set_current_state(state); + trace_contention_begin(lock, LCB_F_RT); + ret = task_blocks_on_rt_mutex(lock, waiter, current, ww_ctx, chwalk); if (likely(!ret)) ret = rt_mutex_slowlock_block(lock, ww_ctx, state, NULL, waiter); @@ -1601,6 +1605,9 @@ static int __sched __rt_mutex_slowlock(struct rt_mutex_base *lock, * unconditionally. We might have to fix that up. */ fixup_rt_mutex_waiters(lock); + + trace_contention_end(lock, ret); + return ret; } @@ -1683,6 +1690,8 @@ static void __sched rtlock_slowlock_locked(struct rt_mutex_base *lock) /* Save current state and set state to TASK_RTLOCK_WAIT */ current_save_and_set_rtlock_wait_state(); + trace_contention_begin(lock, LCB_F_RT); + task_blocks_on_rt_mutex(lock, &waiter, current, NULL, RT_MUTEX_MIN_CHAINWALK); for (;;) { @@ -1712,6 +1721,8 @@ static void __sched rtlock_slowlock_locked(struct rt_mutex_base *lock) */ fixup_rt_mutex_waiters(lock); debug_rt_mutex_free_waiter(&waiter); + + trace_contention_end(lock, 0); } static __always_inline void __sched rtlock_slowlock(struct rt_mutex_base *lock) diff --git a/kernel/locking/rwbase_rt.c b/kernel/locking/rwbase_rt.c index 6fd3162e4098..c201aadb9301 100644 --- a/kernel/locking/rwbase_rt.c +++ b/kernel/locking/rwbase_rt.c @@ -112,6 +112,8 @@ static int __sched __rwbase_read_lock(struct rwbase_rt *rwb, * Reader2 to call up_read(), which might be unbound. */ + trace_contention_begin(rwb, LCB_F_RT | LCB_F_READ); + /* * For rwlocks this returns 0 unconditionally, so the below * !ret conditionals are optimized out. @@ -130,6 +132,8 @@ static int __sched __rwbase_read_lock(struct rwbase_rt *rwb, raw_spin_unlock_irq(&rtm->wait_lock); if (!ret) rwbase_rtmutex_unlock(rtm); + + trace_contention_end(rwb, ret); return ret; } @@ -247,11 +251,13 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb, goto out_unlock; rwbase_set_and_save_current_state(state); + trace_contention_begin(rwb, LCB_F_RT | LCB_F_WRITE); for (;;) { /* Optimized out for rwlocks */ if (rwbase_signal_pending_state(state, current)) { rwbase_restore_current_state(); __rwbase_write_unlock(rwb, 0, flags); + trace_contention_end(rwb, -EINTR); return -EINTR; } @@ -265,6 +271,7 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb, set_current_state(state); } rwbase_restore_current_state(); + trace_contention_end(rwb, 0); out_unlock: raw_spin_unlock_irqrestore(&rtm->wait_lock, flags); diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c index acde5d6f1254..9d1db4a54d34 100644 --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -27,6 +27,7 @@ #include <linux/export.h> #include <linux/rwsem.h> #include <linux/atomic.h> +#include <trace/events/lock.h> #ifndef CONFIG_PREEMPT_RT #include "lock_events.h" @@ -375,16 +376,19 @@ rwsem_add_waiter(struct rw_semaphore *sem, struct rwsem_waiter *waiter) * * Both rwsem_mark_wake() and rwsem_try_write_lock() contain a full 'copy' of * this function. Modify with care. + * + * Return: true if wait_list isn't empty and false otherwise */ -static inline void +static inline bool rwsem_del_waiter(struct rw_semaphore *sem, struct rwsem_waiter *waiter) { lockdep_assert_held(&sem->wait_lock); list_del(&waiter->list); if (likely(!list_empty(&sem->wait_list))) - return; + return true; atomic_long_andnot(RWSEM_FLAG_HANDOFF | RWSEM_FLAG_WAITERS, &sem->count); + return false; } /* @@ -559,6 +563,33 @@ static void rwsem_mark_wake(struct rw_semaphore *sem, } /* + * Remove a waiter and try to wake up other waiters in the wait queue + * This function is called from the out_nolock path of both the reader and + * writer slowpaths with wait_lock held. It releases the wait_lock and + * optionally wake up waiters before it returns. + */ +static inline void +rwsem_del_wake_waiter(struct rw_semaphore *sem, struct rwsem_waiter *waiter, + struct wake_q_head *wake_q) + __releases(&sem->wait_lock) +{ + bool first = rwsem_first_waiter(sem) == waiter; + + wake_q_init(wake_q); + + /* + * If the wait_list isn't empty and the waiter to be deleted is + * the first waiter, we wake up the remaining waiters as they may + * be eligible to acquire or spin on the lock. + */ + if (rwsem_del_waiter(sem, waiter) && first) + rwsem_mark_wake(sem, RWSEM_WAKE_ANY, wake_q); + raw_spin_unlock_irq(&sem->wait_lock); + if (!wake_q_empty(wake_q)) + wake_up_q(wake_q); +} + +/* * This function must be called with the sem->wait_lock held to prevent * race conditions between checking the rwsem wait list and setting the * sem->count accordingly. @@ -901,7 +932,7 @@ done: */ static inline void clear_nonspinnable(struct rw_semaphore *sem) { - if (rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)) + if (unlikely(rwsem_test_oflags(sem, RWSEM_NONSPINNABLE))) atomic_long_andnot(RWSEM_NONSPINNABLE, &sem->owner); } @@ -926,6 +957,31 @@ rwsem_spin_on_owner(struct rw_semaphore *sem) #endif /* + * Prepare to wake up waiter(s) in the wait queue by putting them into the + * given wake_q if the rwsem lock owner isn't a writer. If rwsem is likely + * reader-owned, wake up read lock waiters in queue front or wake up any + * front waiter otherwise. + + * This is being called from both reader and writer slow paths. + */ +static inline void rwsem_cond_wake_waiter(struct rw_semaphore *sem, long count, + struct wake_q_head *wake_q) +{ + enum rwsem_wake_type wake_type; + + if (count & RWSEM_WRITER_MASK) + return; + + if (count & RWSEM_READER_MASK) { + wake_type = RWSEM_WAKE_READERS; + } else { + wake_type = RWSEM_WAKE_ANY; + clear_nonspinnable(sem); + } + rwsem_mark_wake(sem, wake_type, wake_q); +} + +/* * Wait for the read lock to be granted */ static struct rw_semaphore __sched * @@ -935,7 +991,6 @@ rwsem_down_read_slowpath(struct rw_semaphore *sem, long count, unsigned int stat long rcnt = (count >> RWSEM_READER_SHIFT); struct rwsem_waiter waiter; DEFINE_WAKE_Q(wake_q); - bool wake = false; /* * To prevent a constant stream of readers from starving a sleeping @@ -977,12 +1032,11 @@ queue: if (list_empty(&sem->wait_list)) { /* * In case the wait queue is empty and the lock isn't owned - * by a writer or has the handoff bit set, this reader can - * exit the slowpath and return immediately as its - * RWSEM_READER_BIAS has already been set in the count. + * by a writer, this reader can exit the slowpath and return + * immediately as its RWSEM_READER_BIAS has already been set + * in the count. */ - if (!(atomic_long_read(&sem->count) & - (RWSEM_WRITER_MASK | RWSEM_FLAG_HANDOFF))) { + if (!(atomic_long_read(&sem->count) & RWSEM_WRITER_MASK)) { /* Provide lock ACQUIRE */ smp_acquire__after_ctrl_dep(); raw_spin_unlock_irq(&sem->wait_lock); @@ -997,22 +1051,13 @@ queue: /* we're now waiting on the lock, but no longer actively locking */ count = atomic_long_add_return(adjustment, &sem->count); - /* - * If there are no active locks, wake the front queued process(es). - * - * If there are no writers and we are first in the queue, - * wake our own waiter to join the existing active readers ! - */ - if (!(count & RWSEM_LOCK_MASK)) { - clear_nonspinnable(sem); - wake = true; - } - if (wake || (!(count & RWSEM_WRITER_MASK) && - (adjustment & RWSEM_FLAG_WAITERS))) - rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q); - + rwsem_cond_wake_waiter(sem, count, &wake_q); raw_spin_unlock_irq(&sem->wait_lock); - wake_up_q(&wake_q); + + if (!wake_q_empty(&wake_q)) + wake_up_q(&wake_q); + + trace_contention_begin(sem, LCB_F_READ); /* wait to be given the lock */ for (;;) { @@ -1035,13 +1080,14 @@ queue: __set_current_state(TASK_RUNNING); lockevent_inc(rwsem_rlock); + trace_contention_end(sem, 0); return sem; out_nolock: - rwsem_del_waiter(sem, &waiter); - raw_spin_unlock_irq(&sem->wait_lock); + rwsem_del_wake_waiter(sem, &waiter, &wake_q); __set_current_state(TASK_RUNNING); lockevent_inc(rwsem_rlock_fail); + trace_contention_end(sem, -EINTR); return ERR_PTR(-EINTR); } @@ -1051,7 +1097,6 @@ out_nolock: static struct rw_semaphore __sched * rwsem_down_write_slowpath(struct rw_semaphore *sem, int state) { - long count; struct rwsem_waiter waiter; DEFINE_WAKE_Q(wake_q); @@ -1075,23 +1120,8 @@ rwsem_down_write_slowpath(struct rw_semaphore *sem, int state) /* we're now waiting on the lock */ if (rwsem_first_waiter(sem) != &waiter) { - count = atomic_long_read(&sem->count); - - /* - * If there were already threads queued before us and: - * 1) there are no active locks, wake the front - * queued process(es) as the handoff bit might be set. - * 2) there are no active writers and some readers, the lock - * must be read owned; so we try to wake any read lock - * waiters that were queued ahead of us. - */ - if (count & RWSEM_WRITER_MASK) - goto wait; - - rwsem_mark_wake(sem, (count & RWSEM_READER_MASK) - ? RWSEM_WAKE_READERS - : RWSEM_WAKE_ANY, &wake_q); - + rwsem_cond_wake_waiter(sem, atomic_long_read(&sem->count), + &wake_q); if (!wake_q_empty(&wake_q)) { /* * We want to minimize wait_lock hold time especially @@ -1099,16 +1129,16 @@ rwsem_down_write_slowpath(struct rw_semaphore *sem, int state) */ raw_spin_unlock_irq(&sem->wait_lock); wake_up_q(&wake_q); - wake_q_init(&wake_q); /* Used again, reinit */ raw_spin_lock_irq(&sem->wait_lock); } } else { atomic_long_or(RWSEM_FLAG_WAITERS, &sem->count); } -wait: /* wait until we successfully acquire the lock */ set_current_state(state); + trace_contention_begin(sem, LCB_F_WRITE); + for (;;) { if (rwsem_try_write_lock(sem, &waiter)) { /* rwsem_try_write_lock() implies ACQUIRE on success */ @@ -1148,17 +1178,15 @@ trylock_again: __set_current_state(TASK_RUNNING); raw_spin_unlock_irq(&sem->wait_lock); lockevent_inc(rwsem_wlock); + trace_contention_end(sem, 0); return sem; out_nolock: __set_current_state(TASK_RUNNING); raw_spin_lock_irq(&sem->wait_lock); - rwsem_del_waiter(sem, &waiter); - if (!list_empty(&sem->wait_list)) - rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q); - raw_spin_unlock_irq(&sem->wait_lock); - wake_up_q(&wake_q); + rwsem_del_wake_waiter(sem, &waiter, &wake_q); lockevent_inc(rwsem_wlock_fail); + trace_contention_end(sem, -EINTR); return ERR_PTR(-EINTR); } diff --git a/kernel/locking/semaphore.c b/kernel/locking/semaphore.c index 9ee381e4d2a4..f2654d2fe43a 100644 --- a/kernel/locking/semaphore.c +++ b/kernel/locking/semaphore.c @@ -32,6 +32,7 @@ #include <linux/semaphore.h> #include <linux/spinlock.h> #include <linux/ftrace.h> +#include <trace/events/lock.h> static noinline void __down(struct semaphore *sem); static noinline int __down_interruptible(struct semaphore *sem); @@ -205,7 +206,7 @@ struct semaphore_waiter { * constant, and thus optimised away by the compiler. Likewise the * 'timeout' parameter for the cases without timeouts. */ -static inline int __sched __down_common(struct semaphore *sem, long state, +static inline int __sched ___down_common(struct semaphore *sem, long state, long timeout) { struct semaphore_waiter waiter; @@ -236,6 +237,18 @@ static inline int __sched __down_common(struct semaphore *sem, long state, return -EINTR; } +static inline int __sched __down_common(struct semaphore *sem, long state, + long timeout) +{ + int ret; + + trace_contention_begin(sem, 0); + ret = ___down_common(sem, state, timeout); + trace_contention_end(sem, ret); + + return ret; +} + static noinline void __sched __down(struct semaphore *sem) { __down_common(sem, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); |