From dcf6ac497505987033baebaf5a49f37ebfadb272 Mon Sep 17 00:00:00 2001 From: ko1 Date: Tue, 1 Sep 2015 09:08:42 +0000 Subject: * thread_tools.c: rename thread_tools.c to thread_sync.c. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51730 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- thread_sync.c | 1335 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1335 insertions(+) create mode 100644 thread_sync.c (limited to 'thread_sync.c') diff --git a/thread_sync.c b/thread_sync.c new file mode 100644 index 0000000000..c99f54cb82 --- /dev/null +++ b/thread_sync.c @@ -0,0 +1,1335 @@ +/* included by thraed.c */ + +VALUE rb_cMutex, rb_cQueue, rb_cSizedQueue, rb_cConditionVariable; +VALUE rb_eClosedQueueError; + +/* Mutex */ + +typedef struct rb_mutex_struct { + rb_nativethread_lock_t lock; + rb_nativethread_cond_t cond; + struct rb_thread_struct volatile *th; + struct rb_mutex_struct *next_mutex; + int cond_waiting; + int allow_trap; +} rb_mutex_t; + +static void rb_mutex_abandon_all(rb_mutex_t *mutexes); +static void rb_mutex_abandon_keeping_mutexes(rb_thread_t *th); +static void rb_mutex_abandon_locking_mutex(rb_thread_t *th); +static const char* rb_mutex_unlock_th(rb_mutex_t *mutex, rb_thread_t volatile *th); + +/* + * Document-class: Mutex + * + * Mutex implements a simple semaphore that can be used to coordinate access to + * shared data from multiple concurrent threads. + * + * Example: + * + * require 'thread' + * semaphore = Mutex.new + * + * a = Thread.new { + * semaphore.synchronize { + * # access shared resource + * } + * } + * + * b = Thread.new { + * semaphore.synchronize { + * # access shared resource + * } + * } + * + */ + +#define GetMutexPtr(obj, tobj) \ + TypedData_Get_Struct((obj), rb_mutex_t, &mutex_data_type, (tobj)) + +#define mutex_mark NULL + +static void +mutex_free(void *ptr) +{ + if (ptr) { + rb_mutex_t *mutex = ptr; + if (mutex->th) { + /* rb_warn("free locked mutex"); */ + const char *err = rb_mutex_unlock_th(mutex, mutex->th); + if (err) rb_bug("%s", err); + } + native_mutex_destroy(&mutex->lock); + native_cond_destroy(&mutex->cond); + } + ruby_xfree(ptr); +} + +static size_t +mutex_memsize(const void *ptr) +{ + return ptr ? sizeof(rb_mutex_t) : 0; +} + +static const rb_data_type_t mutex_data_type = { + "mutex", + {mutex_mark, mutex_free, mutex_memsize,}, + 0, 0, RUBY_TYPED_FREE_IMMEDIATELY +}; + +VALUE +rb_obj_is_mutex(VALUE obj) +{ + if (rb_typeddata_is_kind_of(obj, &mutex_data_type)) { + return Qtrue; + } + else { + return Qfalse; + } +} + +static VALUE +mutex_alloc(VALUE klass) +{ + VALUE obj; + rb_mutex_t *mutex; + + obj = TypedData_Make_Struct(klass, rb_mutex_t, &mutex_data_type, mutex); + native_mutex_initialize(&mutex->lock); + native_cond_initialize(&mutex->cond, RB_CONDATTR_CLOCK_MONOTONIC); + return obj; +} + +/* + * call-seq: + * Mutex.new -> mutex + * + * Creates a new Mutex + */ +static VALUE +mutex_initialize(VALUE self) +{ + return self; +} + +VALUE +rb_mutex_new(void) +{ + return mutex_alloc(rb_cMutex); +} + +/* + * call-seq: + * mutex.locked? -> true or false + * + * Returns +true+ if this lock is currently held by some thread. + */ +VALUE +rb_mutex_locked_p(VALUE self) +{ + rb_mutex_t *mutex; + GetMutexPtr(self, mutex); + return mutex->th ? Qtrue : Qfalse; +} + +static void +mutex_locked(rb_thread_t *th, VALUE self) +{ + rb_mutex_t *mutex; + GetMutexPtr(self, mutex); + + if (th->keeping_mutexes) { + mutex->next_mutex = th->keeping_mutexes; + } + th->keeping_mutexes = mutex; +} + +/* + * call-seq: + * mutex.try_lock -> true or false + * + * Attempts to obtain the lock and returns immediately. Returns +true+ if the + * lock was granted. + */ +VALUE +rb_mutex_trylock(VALUE self) +{ + rb_mutex_t *mutex; + VALUE locked = Qfalse; + GetMutexPtr(self, mutex); + + native_mutex_lock(&mutex->lock); + if (mutex->th == 0) { + rb_thread_t *th = GET_THREAD(); + mutex->th = th; + locked = Qtrue; + + mutex_locked(th, self); + } + native_mutex_unlock(&mutex->lock); + + return locked; +} + +static int +lock_func(rb_thread_t *th, rb_mutex_t *mutex, int timeout_ms) +{ + int interrupted = 0; + int err = 0; + + mutex->cond_waiting++; + for (;;) { + if (!mutex->th) { + mutex->th = th; + break; + } + if (RUBY_VM_INTERRUPTED(th)) { + interrupted = 1; + break; + } + if (err == ETIMEDOUT) { + interrupted = 2; + break; + } + + if (timeout_ms) { + struct timespec timeout_rel; + struct timespec timeout; + + timeout_rel.tv_sec = 0; + timeout_rel.tv_nsec = timeout_ms * 1000 * 1000; + timeout = native_cond_timeout(&mutex->cond, timeout_rel); + err = native_cond_timedwait(&mutex->cond, &mutex->lock, &timeout); + } + else { + native_cond_wait(&mutex->cond, &mutex->lock); + err = 0; + } + } + mutex->cond_waiting--; + + return interrupted; +} + +static void +lock_interrupt(void *ptr) +{ + rb_mutex_t *mutex = (rb_mutex_t *)ptr; + native_mutex_lock(&mutex->lock); + if (mutex->cond_waiting > 0) + native_cond_broadcast(&mutex->cond); + native_mutex_unlock(&mutex->lock); +} + +/* + * At maximum, only one thread can use cond_timedwait and watch deadlock + * periodically. Multiple polling thread (i.e. concurrent deadlock check) + * introduces new race conditions. [Bug #6278] [ruby-core:44275] + */ +static const rb_thread_t *patrol_thread = NULL; + +/* + * call-seq: + * mutex.lock -> self + * + * Attempts to grab the lock and waits if it isn't available. + * Raises +ThreadError+ if +mutex+ was locked by the current thread. + */ +VALUE +rb_mutex_lock(VALUE self) +{ + rb_thread_t *th = GET_THREAD(); + rb_mutex_t *mutex; + GetMutexPtr(self, mutex); + + /* When running trap handler */ + if (!mutex->allow_trap && th->interrupt_mask & TRAP_INTERRUPT_MASK) { + rb_raise(rb_eThreadError, "can't be called from trap context"); + } + + if (rb_mutex_trylock(self) == Qfalse) { + if (mutex->th == th) { + rb_raise(rb_eThreadError, "deadlock; recursive locking"); + } + + while (mutex->th != th) { + int interrupted; + enum rb_thread_status prev_status = th->status; + volatile int timeout_ms = 0; + struct rb_unblock_callback oldubf; + + set_unblock_function(th, lock_interrupt, mutex, &oldubf, FALSE); + th->status = THREAD_STOPPED_FOREVER; + th->locking_mutex = self; + + native_mutex_lock(&mutex->lock); + th->vm->sleeper++; + /* + * Carefully! while some contended threads are in lock_func(), + * vm->sleepr is unstable value. we have to avoid both deadlock + * and busy loop. + */ + if ((vm_living_thread_num(th->vm) == th->vm->sleeper) && + !patrol_thread) { + timeout_ms = 100; + patrol_thread = th; + } + + GVL_UNLOCK_BEGIN(); + interrupted = lock_func(th, mutex, (int)timeout_ms); + native_mutex_unlock(&mutex->lock); + GVL_UNLOCK_END(); + + if (patrol_thread == th) + patrol_thread = NULL; + + reset_unblock_function(th, &oldubf); + + th->locking_mutex = Qfalse; + if (mutex->th && interrupted == 2) { + rb_check_deadlock(th->vm); + } + if (th->status == THREAD_STOPPED_FOREVER) { + th->status = prev_status; + } + th->vm->sleeper--; + + if (mutex->th == th) mutex_locked(th, self); + + if (interrupted) { + RUBY_VM_CHECK_INTS_BLOCKING(th); + } + } + } + return self; +} + +/* + * call-seq: + * mutex.owned? -> true or false + * + * Returns +true+ if this lock is currently held by current thread. + */ +VALUE +rb_mutex_owned_p(VALUE self) +{ + VALUE owned = Qfalse; + rb_thread_t *th = GET_THREAD(); + rb_mutex_t *mutex; + + GetMutexPtr(self, mutex); + + if (mutex->th == th) + owned = Qtrue; + + return owned; +} + +static const char * +rb_mutex_unlock_th(rb_mutex_t *mutex, rb_thread_t volatile *th) +{ + const char *err = NULL; + + native_mutex_lock(&mutex->lock); + + if (mutex->th == 0) { + err = "Attempt to unlock a mutex which is not locked"; + } + else if (mutex->th != th) { + err = "Attempt to unlock a mutex which is locked by another thread"; + } + else { + mutex->th = 0; + if (mutex->cond_waiting > 0) + native_cond_signal(&mutex->cond); + } + + native_mutex_unlock(&mutex->lock); + + if (!err) { + rb_mutex_t *volatile *th_mutex = &th->keeping_mutexes; + while (*th_mutex != mutex) { + th_mutex = &(*th_mutex)->next_mutex; + } + *th_mutex = mutex->next_mutex; + mutex->next_mutex = NULL; + } + + return err; +} + +/* + * call-seq: + * mutex.unlock -> self + * + * Releases the lock. + * Raises +ThreadError+ if +mutex+ wasn't locked by the current thread. + */ +VALUE +rb_mutex_unlock(VALUE self) +{ + const char *err; + rb_mutex_t *mutex; + GetMutexPtr(self, mutex); + + err = rb_mutex_unlock_th(mutex, GET_THREAD()); + if (err) rb_raise(rb_eThreadError, "%s", err); + + return self; +} + +static void +rb_mutex_abandon_keeping_mutexes(rb_thread_t *th) +{ + if (th->keeping_mutexes) { + rb_mutex_abandon_all(th->keeping_mutexes); + } + th->keeping_mutexes = NULL; +} + +static void +rb_mutex_abandon_locking_mutex(rb_thread_t *th) +{ + rb_mutex_t *mutex; + + if (!th->locking_mutex) return; + + GetMutexPtr(th->locking_mutex, mutex); + if (mutex->th == th) + rb_mutex_abandon_all(mutex); + th->locking_mutex = Qfalse; +} + +static void +rb_mutex_abandon_all(rb_mutex_t *mutexes) +{ + rb_mutex_t *mutex; + + while (mutexes) { + mutex = mutexes; + mutexes = mutex->next_mutex; + mutex->th = 0; + mutex->next_mutex = 0; + } +} + +static VALUE +rb_mutex_sleep_forever(VALUE time) +{ + sleep_forever(GET_THREAD(), 1, 0); /* permit spurious check */ + return Qnil; +} + +static VALUE +rb_mutex_wait_for(VALUE time) +{ + struct timeval *t = (struct timeval *)time; + sleep_timeval(GET_THREAD(), *t, 0); /* permit spurious check */ + return Qnil; +} + +VALUE +rb_mutex_sleep(VALUE self, VALUE timeout) +{ + time_t beg, end; + struct timeval t; + + if (!NIL_P(timeout)) { + t = rb_time_interval(timeout); + } + rb_mutex_unlock(self); + beg = time(0); + if (NIL_P(timeout)) { + rb_ensure(rb_mutex_sleep_forever, Qnil, rb_mutex_lock, self); + } + else { + rb_ensure(rb_mutex_wait_for, (VALUE)&t, rb_mutex_lock, self); + } + end = time(0) - beg; + return INT2FIX(end); +} + +/* + * call-seq: + * mutex.sleep(timeout = nil) -> number + * + * Releases the lock and sleeps +timeout+ seconds if it is given and + * non-nil or forever. Raises +ThreadError+ if +mutex+ wasn't locked by + * the current thread. + * + * When the thread is next woken up, it will attempt to reacquire + * the lock. + * + * Note that this method can wakeup without explicit Thread#wakeup call. + * For example, receiving signal and so on. + */ +static VALUE +mutex_sleep(int argc, VALUE *argv, VALUE self) +{ + VALUE timeout; + + rb_scan_args(argc, argv, "01", &timeout); + return rb_mutex_sleep(self, timeout); +} + +/* + * call-seq: + * mutex.synchronize { ... } -> result of the block + * + * Obtains a lock, runs the block, and releases the lock when the block + * completes. See the example under +Mutex+. + */ + +VALUE +rb_mutex_synchronize(VALUE mutex, VALUE (*func)(VALUE arg), VALUE arg) +{ + rb_mutex_lock(mutex); + return rb_ensure(func, arg, rb_mutex_unlock, mutex); +} + +/* + * call-seq: + * mutex.synchronize { ... } -> result of the block + * + * Obtains a lock, runs the block, and releases the lock when the block + * completes. See the example under +Mutex+. + */ +static VALUE +rb_mutex_synchronize_m(VALUE self, VALUE args) +{ + if (!rb_block_given_p()) { + rb_raise(rb_eThreadError, "must be called with a block"); + } + + return rb_mutex_synchronize(self, rb_yield, Qundef); +} + +void rb_mutex_allow_trap(VALUE self, int val) +{ + rb_mutex_t *m; + GetMutexPtr(self, m); + + m->allow_trap = val; +} + +/* Queue */ + +enum { + QUEUE_QUE, + QUEUE_WAITERS, + SZQUEUE_WAITERS, + SZQUEUE_MAX, + END_QUEUE +}; + +#define QUEUE_CLOSED FL_USER5 +#define QUEUE_CLOSE_EXCEPTION FL_USER6 + +#define GET_QUEUE_QUE(q) get_array((q), QUEUE_QUE) +#define GET_QUEUE_WAITERS(q) get_array((q), QUEUE_WAITERS) +#define GET_SZQUEUE_WAITERS(q) get_array((q), SZQUEUE_WAITERS) +#define GET_SZQUEUE_MAX(q) RSTRUCT_GET((q), SZQUEUE_MAX) +#define GET_SZQUEUE_ULONGMAX(q) NUM2ULONG(GET_SZQUEUE_MAX(q)) + +static VALUE +ary_buf_new(void) +{ + return rb_ary_tmp_new(1); +} + +static VALUE +get_array(VALUE obj, int idx) +{ + VALUE ary = RSTRUCT_GET(obj, idx); + if (!RB_TYPE_P(ary, T_ARRAY)) { + rb_raise(rb_eTypeError, "%+"PRIsVALUE" not initialized", obj); + } + return ary; +} + +static void +wakeup_first_thread(VALUE list) +{ + VALUE thread; + + while (!NIL_P(thread = rb_ary_shift(list))) { + if (RTEST(rb_thread_wakeup_alive(thread))) break; + } +} + +static void +wakeup_all_threads(VALUE list) +{ + VALUE thread; + long i; + + for (i=0; i 0) { + VALUE waiters = GET_QUEUE_WAITERS(self); + wakeup_all_threads(waiters); + } + + if (is_szq && szqueue_num_waiting_producer(self) > 0) { + VALUE waiters = GET_SZQUEUE_WAITERS(self); + wakeup_all_threads(waiters); + } + + return self; +} + +/* + * Document-class: Queue + * + * This class provides a way to synchronize communication between threads. + * + * Example: + * + * require 'thread' + * queue = Queue.new + * + * producer = Thread.new do + * 5.times do |i| + * sleep rand(i) # simulate expense + * queue << i + * puts "#{i} produced" + * end + * end + * + * consumer = Thread.new do + * 5.times do |i| + * value = queue.pop + * sleep rand(i/2) # simulate expense + * puts "consumed #{value}" + * end + * end + * + */ + +/* + * Document-method: Queue::new + * + * Creates a new queue instance. + */ + +static VALUE +rb_queue_initialize(VALUE self) +{ + RSTRUCT_SET(self, QUEUE_QUE, ary_buf_new()); + RSTRUCT_SET(self, QUEUE_WAITERS, ary_buf_new()); + return self; +} + +static VALUE +queue_do_push(VALUE self, VALUE obj) +{ + if (queue_closed_p(self)) { + raise_closed_queue_error(self); + } + rb_ary_push(GET_QUEUE_QUE(self), obj); + wakeup_first_thread(GET_QUEUE_WAITERS(self)); + return self; +} + +/* + * Document-method: Queue#close + * call-seq: + * close(exception=false) + * + * Closes the queue. A closed queue cannot be re-opened. + * + * After the call to close completes, the following are true: + * + * - +closed?+ will return true + * + * - calling enq/push/<< will raise ClosedQueueError('queue closed') + * + * - when +empty?+ is false, calling deq/pop/shift will return an object + * from the queue as usual. + * + * - when +empty?+ is true, deq(non_block=false) will not suspend and + * will either return nil. If +exception+ parameter is true, raise ClosedQueueError error. + * deq(non_block=true) will ignore the parameter and raise a ThreadError('queue empty'). + * + * ClosedQueueError is inherited from StopIteration, so that you can break loop block. + * + * Example: + * + * q = Queue.new + * Thread.new{ + * while e = q.deq # wait for nil to break loop + * # ... + * end + * } + * q.close # equals to q.close(false) + * + * q = Queue.new + * Thread.new{ + * loop{ + * e = q.deq; ... # braek with ClosedQueueError + * } + * } + * q.close(true) + */ + +static VALUE +rb_queue_close(int argc, VALUE *argv, VALUE self) +{ + return queue_do_close(self, argc, argv, FALSE); +} + +/* + * Document-method: Queue#closed? + * call-seq: closed? + * + * Returns +true+ if the queue is closed. + */ + +static VALUE +rb_queue_closed_p(VALUE self) +{ + return queue_closed_p(self) ? Qtrue : Qfalse; +} + +/* + * Document-method: Queue#push + * call-seq: + * push(object) + * enq(object) + * <<(object) + * + * Pushes the given +object+ to the queue. + */ + +static VALUE +rb_queue_push(VALUE self, VALUE obj) +{ + return queue_do_push(self, obj); +} + +struct waiting_delete { + VALUE waiting; + VALUE th; +}; + +static VALUE +queue_delete_from_waiting(struct waiting_delete *p) +{ + rb_ary_delete(p->waiting, p->th); + return Qnil; +} + +static VALUE +queue_sleep(VALUE arg) +{ + rb_thread_sleep_deadly(); + return Qnil; +} + +static VALUE +queue_do_pop(VALUE self, int should_block) +{ + struct waiting_delete args; + args.waiting = GET_QUEUE_WAITERS(self); + args.th = rb_thread_current(); + + while (queue_length(self) == 0) { + if (!should_block) { + rb_raise(rb_eThreadError, "queue empty"); + } + else if (queue_closed_p(self)) { + return queue_closed_result(self); + } + else { + assert(queue_length(self) == 0); + assert(queue_closed_p(self) == 0); + + rb_ary_push(args.waiting, args.th); + rb_ensure(queue_sleep, (VALUE)0, queue_delete_from_waiting, (VALUE)&args); + } + } + + return rb_ary_shift(GET_QUEUE_QUE(self)); +} + +static int +queue_pop_should_block(int argc, const VALUE *argv) +{ + int should_block = 1; + rb_check_arity(argc, 0, 1); + if (argc > 0) { + should_block = !RTEST(argv[0]); + } + return should_block; +} + +/* + * Document-method: Queue#pop + * call-seq: + * pop(non_block=false) + * deq(non_block=false) + * shift(non_block=false) + * + * Retrieves data from the queue. + * + * If the queue is empty, the calling thread is suspended until data is pushed + * onto the queue. If +non_block+ is true, the thread isn't suspended, and an + * exception is raised. + */ + +static VALUE +rb_queue_pop(int argc, VALUE *argv, VALUE self) +{ + int should_block = queue_pop_should_block(argc, argv); + return queue_do_pop(self, should_block); +} + +/* + * Document-method: Queue#empty? + * call-seq: empty? + * + * Returns +true+ if the queue is empty. + */ + +static VALUE +rb_queue_empty_p(VALUE self) +{ + return queue_length(self) == 0 ? Qtrue : Qfalse; +} + +/* + * Document-method: Queue#clear + * + * Removes all objects from the queue. + */ + +static VALUE +rb_queue_clear(VALUE self) +{ + rb_ary_clear(GET_QUEUE_QUE(self)); + return self; +} + +/* + * Document-method: Queue#length + * call-seq: + * length + * size + * + * Returns the length of the queue. + */ + +static VALUE +rb_queue_length(VALUE self) +{ + unsigned long len = queue_length(self); + return ULONG2NUM(len); +} + +/* + * Document-method: Queue#num_waiting + * + * Returns the number of threads waiting on the queue. + */ + +static VALUE +rb_queue_num_waiting(VALUE self) +{ + unsigned long len = queue_num_waiting(self); + return ULONG2NUM(len); +} + +/* + * Document-class: SizedQueue + * + * This class represents queues of specified size capacity. The push operation + * may be blocked if the capacity is full. + * + * See Queue for an example of how a SizedQueue works. + */ + +/* + * Document-method: SizedQueue::new + * call-seq: new(max) + * + * Creates a fixed-length queue with a maximum size of +max+. + */ + +static VALUE +rb_szqueue_initialize(VALUE self, VALUE vmax) +{ + long max; + + max = NUM2LONG(vmax); + if (max <= 0) { + rb_raise(rb_eArgError, "queue size must be positive"); + } + + RSTRUCT_SET(self, QUEUE_QUE, ary_buf_new()); + RSTRUCT_SET(self, QUEUE_WAITERS, ary_buf_new()); + RSTRUCT_SET(self, SZQUEUE_WAITERS, ary_buf_new()); + RSTRUCT_SET(self, SZQUEUE_MAX, vmax); + + return self; +} + +/* + * Document-method: SizedQueue#close + * call-seq: + * close(exception=false) + * + * Similar to Queue#close. + * + * The difference is behavior with waiting enqueuing threads. + * + * If there are waiting enqueuing threads, they are interrupted by + * raising ClosedQueueError('queue closed'). + */ +static VALUE +rb_szqueue_close(int argc, VALUE *argv, VALUE self) +{ + return queue_do_close(self, argc, argv, TRUE); +} + +/* + * Document-method: SizedQueue#max + * + * Returns the maximum size of the queue. + */ + +static VALUE +rb_szqueue_max_get(VALUE self) +{ + return GET_SZQUEUE_MAX(self); +} + +/* + * Document-method: SizedQueue#max= + * call-seq: max=(number) + * + * Sets the maximum size of the queue to the given +number+. + */ + +static VALUE +rb_szqueue_max_set(VALUE self, VALUE vmax) +{ + long max = NUM2LONG(vmax), diff = 0; + VALUE t; + + if (max <= 0) { + rb_raise(rb_eArgError, "queue size must be positive"); + } + if ((unsigned long)max > GET_SZQUEUE_ULONGMAX(self)) { + diff = max - GET_SZQUEUE_ULONGMAX(self); + } + RSTRUCT_SET(self, SZQUEUE_MAX, vmax); + while (diff-- > 0 && !NIL_P(t = rb_ary_shift(GET_SZQUEUE_WAITERS(self)))) { + rb_thread_wakeup_alive(t); + } + return vmax; +} + +static int +szqueue_push_should_block(int argc, const VALUE *argv) +{ + int should_block = 1; + rb_check_arity(argc, 1, 2); + if (argc > 1) { + should_block = !RTEST(argv[1]); + } + return should_block; +} + +/* + * Document-method: SizedQueue#push + * call-seq: + * push(object, non_block=false) + * enq(object, non_block=false) + * <<(object) + * + * Pushes +object+ to the queue. + * + * If there is no space left in the queue, waits until space becomes + * available, unless +non_block+ is true. If +non_block+ is true, the + * thread isn't suspended, and an exception is raised. + */ + +static VALUE +rb_szqueue_push(int argc, VALUE *argv, VALUE self) +{ + struct waiting_delete args; + int should_block = szqueue_push_should_block(argc, argv); + args.waiting = GET_SZQUEUE_WAITERS(self); + args.th = rb_thread_current(); + + while (queue_length(self) >= GET_SZQUEUE_ULONGMAX(self)) { + if (!should_block) { + rb_raise(rb_eThreadError, "queue full"); + } + else if (queue_closed_p(self)) { + goto closed; + } + else { + rb_ary_push(args.waiting, args.th); + rb_ensure((VALUE (*)())rb_thread_sleep_deadly, (VALUE)0, queue_delete_from_waiting, (VALUE)&args); + } + } + + if (queue_closed_p(self)) { + closed: + raise_closed_queue_error(self); + } + + return queue_do_push(self, argv[0]); +} + +static VALUE +szqueue_do_pop(VALUE self, int should_block) +{ + VALUE retval = queue_do_pop(self, should_block); + + if (queue_length(self) < GET_SZQUEUE_ULONGMAX(self)) { + wakeup_first_thread(GET_SZQUEUE_WAITERS(self)); + } + + return retval; +} + +/* + * Document-method: SizedQueue#pop + * call-seq: + * pop(non_block=false) + * deq(non_block=false) + * shift(non_block=false) + * + * Retrieves data from the queue. + * + * If the queue is empty, the calling thread is suspended until data is pushed + * onto the queue. If +non_block+ is true, the thread isn't suspended, and an + * exception is raised. + */ + +static VALUE +rb_szqueue_pop(int argc, VALUE *argv, VALUE self) +{ + int should_block = queue_pop_should_block(argc, argv); + return szqueue_do_pop(self, should_block); +} + +/* + * Document-method: Queue#clear + * + * Removes all objects from the queue. + */ + +static VALUE +rb_szqueue_clear(VALUE self) +{ + rb_ary_clear(GET_QUEUE_QUE(self)); + wakeup_all_threads(GET_SZQUEUE_WAITERS(self)); + return self; +} + +/* + * Document-method: SizedQueue#num_waiting + * + * Returns the number of threads waiting on the queue. + */ + +static VALUE +rb_szqueue_num_waiting(VALUE self) +{ + long len = queue_num_waiting(self) + szqueue_num_waiting_producer(self); + return ULONG2NUM(len); +} + +/* ConditionalVariable */ + +enum { + CONDVAR_WAITERS, + END_CONDVAR +}; + +#define GET_CONDVAR_WAITERS(cv) get_array((cv), CONDVAR_WAITERS) + +/* + * Document-class: ConditionVariable + * + * ConditionVariable objects augment class Mutex. Using condition variables, + * it is possible to suspend while in the middle of a critical section until a + * resource becomes available. + * + * Example: + * + * require 'thread' + * + * mutex = Mutex.new + * resource = ConditionVariable.new + * + * a = Thread.new { + * mutex.synchronize { + * # Thread 'a' now needs the resource + * resource.wait(mutex) + * # 'a' can now have the resource + * } + * } + * + * b = Thread.new { + * mutex.synchronize { + * # Thread 'b' has finished using the resource + * resource.signal + * } + * } + */ + +/* + * Document-method: ConditionVariable::new + * + * Creates a new condition variable instance. + */ + +static VALUE +rb_condvar_initialize(VALUE self) +{ + RSTRUCT_SET(self, CONDVAR_WAITERS, ary_buf_new()); + return self; +} + +struct sleep_call { + VALUE mutex; + VALUE timeout; +}; + +static ID id_sleep; + +static VALUE +do_sleep(VALUE args) +{ + struct sleep_call *p = (struct sleep_call *)args; + return rb_funcall2(p->mutex, id_sleep, 1, &p->timeout); +} + +static VALUE +delete_current_thread(VALUE ary) +{ + return rb_ary_delete(ary, rb_thread_current()); +} + +/* + * Document-method: ConditionVariable#wait + * call-seq: wait(mutex, timeout=nil) + * + * Releases the lock held in +mutex+ and waits; reacquires the lock on wakeup. + * + * If +timeout+ is given, this method returns after +timeout+ seconds passed, + * even if no other thread doesn't signal. + */ + +static VALUE +rb_condvar_wait(int argc, VALUE *argv, VALUE self) +{ + VALUE waiters = GET_CONDVAR_WAITERS(self); + VALUE mutex, timeout; + struct sleep_call args; + + rb_scan_args(argc, argv, "11", &mutex, &timeout); + + args.mutex = mutex; + args.timeout = timeout; + rb_ary_push(waiters, rb_thread_current()); + rb_ensure(do_sleep, (VALUE)&args, delete_current_thread, waiters); + + return self; +} + +/* + * Document-method: ConditionVariable#signal + * + * Wakes up the first thread in line waiting for this lock. + */ + +static VALUE +rb_condvar_signal(VALUE self) +{ + wakeup_first_thread(GET_CONDVAR_WAITERS(self)); + return self; +} + +/* + * Document-method: ConditionVariable#broadcast + * + * Wakes up all threads waiting for this lock. + */ + +static VALUE +rb_condvar_broadcast(VALUE self) +{ + wakeup_all_threads(GET_CONDVAR_WAITERS(self)); + return self; +} + +/* :nodoc: */ +static VALUE +undumpable(VALUE obj) +{ + rb_raise(rb_eTypeError, "can't dump %"PRIsVALUE, rb_obj_class(obj)); + UNREACHABLE; +} + +static void +Init_thread_sync(void) +{ +#if 0 + rb_cConditionVariable = rb_define_class("ConditionVariable", rb_cObject); /* teach rdoc ConditionVariable */ + rb_cQueue = rb_define_class("Queue", rb_cObject); /* teach rdoc Queue */ + rb_cSizedQueue = rb_define_class("SizedQueue", rb_cObject); /* teach rdoc SizedQueue */ +#endif + + /* Mutex */ + rb_cMutex = rb_define_class_under(rb_cThread, "Mutex", rb_cObject); + rb_define_alloc_func(rb_cMutex, mutex_alloc); + rb_define_method(rb_cMutex, "initialize", mutex_initialize, 0); + rb_define_method(rb_cMutex, "locked?", rb_mutex_locked_p, 0); + rb_define_method(rb_cMutex, "try_lock", rb_mutex_trylock, 0); + rb_define_method(rb_cMutex, "lock", rb_mutex_lock, 0); + rb_define_method(rb_cMutex, "unlock", rb_mutex_unlock, 0); + rb_define_method(rb_cMutex, "sleep", mutex_sleep, -1); + rb_define_method(rb_cMutex, "synchronize", rb_mutex_synchronize_m, 0); + rb_define_method(rb_cMutex, "owned?", rb_mutex_owned_p, 0); + + /* Queue */ + rb_cQueue = rb_struct_define_without_accessor_under( + rb_cThread, + "Queue", rb_cObject, rb_struct_alloc_noinit, + "que", "waiters", NULL); + + rb_eClosedQueueError = rb_define_class("ClosedQueueError", rb_eStopIteration); + + rb_define_method(rb_cQueue, "initialize", rb_queue_initialize, 0); + rb_undef_method(rb_cQueue, "initialize_copy"); + rb_define_method(rb_cQueue, "marshal_dump", undumpable, 0); + rb_define_method(rb_cQueue, "close", rb_queue_close, -1); + rb_define_method(rb_cQueue, "closed?", rb_queue_closed_p, 0); + rb_define_method(rb_cQueue, "push", rb_queue_push, 1); + rb_define_method(rb_cQueue, "pop", rb_queue_pop, -1); + rb_define_method(rb_cQueue, "empty?", rb_queue_empty_p, 0); + rb_define_method(rb_cQueue, "clear", rb_queue_clear, 0); + rb_define_method(rb_cQueue, "length", rb_queue_length, 0); + rb_define_method(rb_cQueue, "num_waiting", rb_queue_num_waiting, 0); + + rb_define_alias(rb_cQueue, "enq", "push"); /* Alias for #push. */ + rb_define_alias(rb_cQueue, "<<", "push"); /* Alias for #push. */ + rb_define_alias(rb_cQueue, "deq", "pop"); /* Alias for #pop. */ + rb_define_alias(rb_cQueue, "shift", "pop"); /* Alias for #pop. */ + rb_define_alias(rb_cQueue, "size", "length"); /* Alias for #length. */ + + rb_cSizedQueue = rb_struct_define_without_accessor_under( + rb_cThread, + "SizedQueue", rb_cQueue, rb_struct_alloc_noinit, + "que", "waiters", "queue_waiters", "size", NULL); + + rb_define_method(rb_cSizedQueue, "initialize", rb_szqueue_initialize, 1); + rb_define_method(rb_cSizedQueue, "close", rb_szqueue_close, -1); + rb_define_method(rb_cSizedQueue, "max", rb_szqueue_max_get, 0); + rb_define_method(rb_cSizedQueue, "max=", rb_szqueue_max_set, 1); + rb_define_method(rb_cSizedQueue, "push", rb_szqueue_push, -1); + rb_define_method(rb_cSizedQueue, "pop", rb_szqueue_pop, -1); + rb_define_method(rb_cSizedQueue, "clear", rb_szqueue_clear, 0); + rb_define_method(rb_cSizedQueue, "num_waiting", rb_szqueue_num_waiting, 0); + + rb_define_alias(rb_cSizedQueue, "enq", "push"); /* Alias for #push. */ + rb_define_alias(rb_cSizedQueue, "<<", "push"); /* Alias for #push. */ + rb_define_alias(rb_cSizedQueue, "deq", "pop"); /* Alias for #pop. */ + rb_define_alias(rb_cSizedQueue, "shift", "pop"); /* Alias for #pop. */ + + /* CVar */ + rb_cConditionVariable = rb_struct_define_without_accessor_under( + rb_cThread, + "ConditionVariable", rb_cObject, rb_struct_alloc_noinit, + "waiters", NULL); + + id_sleep = rb_intern("sleep"); + + rb_define_method(rb_cConditionVariable, "initialize", rb_condvar_initialize, 0); + rb_undef_method(rb_cConditionVariable, "initialize_copy"); + rb_define_method(rb_cConditionVariable, "marshal_dump", undumpable, 0); + rb_define_method(rb_cConditionVariable, "wait", rb_condvar_wait, -1); + rb_define_method(rb_cConditionVariable, "signal", rb_condvar_signal, 0); + rb_define_method(rb_cConditionVariable, "broadcast", rb_condvar_broadcast, 0); + +#define ALIAS_GLOBAL_CONST(name) do { \ + ID id = rb_intern_const(#name); \ + if (!rb_const_defined_at(rb_cObject, id)) { \ + rb_const_set(rb_cObject, id, rb_c##name); \ + } \ + } while (0) + + ALIAS_GLOBAL_CONST(Mutex); + ALIAS_GLOBAL_CONST(Queue); + ALIAS_GLOBAL_CONST(SizedQueue); + ALIAS_GLOBAL_CONST(ConditionVariable); + rb_provide("thread.rb"); +} -- cgit v1.2.3