-/* $Id$ */
-
-/* Copyright (c) 2007 Arnaud Legrand, Bruno Donnassolo.
- All rights reserved. */
+/* Copyright (c) 2007, 2008, 2009, 2010. The SimGrid Team.
+ * All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_synchro, simix,
- "Logging specific to SIMIX (synchronization)");
+ "Logging specific to SIMIX (synchronization)");
+
+static smx_action_t SIMIX_synchro_wait(smx_host_t smx_host, double timeout);
+static void SIMIX_synchro_finish(smx_action_t action);
+static void _SIMIX_cond_wait(smx_cond_t cond, smx_mutex_t mutex, double timeout,
+ smx_process_t issuer, smx_req_t req);
+static void _SIMIX_sem_wait(smx_sem_t sem, double timeout, smx_process_t issuer,
+ smx_req_t req);
+static void SIMIX_sem_block_onto(smx_sem_t sem);
+
+/***************************** Synchro action *********************************/
+
+static smx_action_t SIMIX_synchro_wait(smx_host_t smx_host, double timeout)
+{
+ smx_action_t action;
+ action = xbt_mallocator_get(simix_global->action_mallocator);
+ action->type = SIMIX_ACTION_SYNCHRO;
+ action->name = xbt_strdup("synchro");
+ action->synchro.sleep =
+ surf_workstation_model->extension.workstation.sleep(smx_host->host, timeout);
+
+ surf_workstation_model->action_data_set(action->synchro.sleep, action);
+ return action;
+}
+
+void SIMIX_synchro_stop_waiting(smx_process_t process, smx_req_t req)
+{
+ switch (req->call) {
+
+ case REQ_MUTEX_LOCK:
+ xbt_swag_remove(process, req->mutex_lock.mutex->sleeping);
+ break;
+
+ case REQ_COND_WAIT:
+ xbt_swag_remove(process, req->cond_wait.cond->sleeping);
+ break;
+
+ case REQ_COND_WAIT_TIMEOUT:
+ xbt_swag_remove(process, req->cond_wait_timeout.cond->sleeping);
+ break;
+
+ case REQ_SEM_ACQUIRE:
+ xbt_swag_remove(process, req->sem_acquire.sem->sleeping);
+ break;
+
+ case REQ_SEM_ACQUIRE_TIMEOUT:
+ xbt_swag_remove(process, req->sem_acquire_timeout.sem->sleeping);
+ break;
+
+ default:
+ THROW_IMPOSSIBLE;
+ }
+}
+
+void SIMIX_synchro_destroy(smx_action_t action)
+{
+ XBT_DEBUG("Destroying synchro %p", action);
+ action->synchro.sleep->model_type->action_unref(action->synchro.sleep);
+ xbt_free(action->name);
+ xbt_mallocator_release(simix_global->action_mallocator, action);
+}
+
+void SIMIX_post_synchro(smx_action_t action)
+{
+ if (surf_workstation_model->action_state_get(action->synchro.sleep) == SURF_ACTION_FAILED)
+ action->state = SIMIX_FAILED;
+ else if(surf_workstation_model->action_state_get(action->synchro.sleep) == SURF_ACTION_DONE)
+ action->state = SIMIX_SRC_TIMEOUT;
+ SIMIX_synchro_finish(action);
+}
+
+static void SIMIX_synchro_finish(smx_action_t action)
+{
+ smx_req_t req = xbt_fifo_shift(action->request_list);
+
+ switch (action->state) {
+
+ case SIMIX_SRC_TIMEOUT:
+ TRY {
+ THROWF(timeout_error, 0, "Synchro's wait timeout");
+ } CATCH(req->issuer->running_ctx->exception) {
+ req->issuer->doexception = 1;
+ }
+ break;
+
+ case SIMIX_FAILED:
+ TRY {
+ THROWF(host_error, 0, "Host failed");
+ } CATCH(req->issuer->running_ctx->exception) {
+ req->issuer->doexception = 1;
+ }
+ break;
-/****************************** Synchronization *******************************/
+ default:
+ THROW_IMPOSSIBLE;
+ break;
+ }
+ SIMIX_synchro_stop_waiting(req->issuer, req);
+ SIMIX_synchro_destroy(action);
+ SIMIX_request_answer(req);
+}
/*********************************** Mutex ************************************/
-smx_mutex_t SIMIX_mutex_init()
-{
- smx_mutex_t m = xbt_new0(s_smx_mutex_t,1);
- s_smx_process_t p; /* useful to initialize sleeping swag */
- /* structures initialization */
- m->using = 0;
- m->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
- return m;
-}
-
-void SIMIX_mutex_lock(smx_mutex_t mutex)
-{
- smx_process_t self = SIMIX_process_self();
-
- xbt_assert0((mutex != NULL), "Invalid parameters");
-
- if (mutex->using) {
- /* somebody using the mutex, block */
- xbt_swag_insert(self, mutex->sleeping);
- self->simdata->mutex = mutex;
- __SIMIX_process_block(-1);
- self->simdata->mutex = NULL;
- mutex->using = 1;
- }
- else {
- /* mutex free */
- mutex->using = 1;
- }
- return;
-}
-/* return 1 if the process got the mutex, else 0. */
-int SIMIX_mutex_trylock(smx_mutex_t mutex)
-{
- xbt_assert0((mutex != NULL), "Invalid parameters");
-
- if (mutex->using)
- return 0;
- else {
- mutex->using = 1;
- return 1;
- }
-}
-
-void SIMIX_mutex_unlock(smx_mutex_t mutex)
-{
- smx_process_t p; /*process to wake up */
-
- xbt_assert0((mutex != NULL), "Invalid parameters");
-
- if (xbt_swag_size(mutex->sleeping) > 0) {
- p = xbt_swag_extract(mutex->sleeping);
- mutex->using = 0;
- __SIMIX_process_unblock(p);
- }
- else {
- /* nobody to wape up */
- mutex->using = 0;
- }
- return;
-}
-
-SIMIX_error_t SIMIX_mutex_destroy(smx_mutex_t mutex)
-{
- if ( mutex == NULL )
- return SIMIX_WARNING;
- else {
- xbt_swag_free(mutex->sleeping);
- xbt_free(mutex);
- return SIMIX_OK;
- }
-}
-
-/******************************** Conditional *********************************/
-smx_cond_t SIMIX_cond_init()
+
+/**
+ * \brief Initialize a mutex.
+ *
+ * Allocs and creates the data for the mutex.
+ * \return A mutex
+ */
+smx_mutex_t SIMIX_mutex_init(void)
{
- smx_cond_t cond = xbt_new0(s_smx_cond_t,1);
- s_smx_process_t p;
-
- cond->sleeping = xbt_swag_new(xbt_swag_offset(p,synchro_hookup));
- cond->actions = xbt_fifo_new();
- cond->mutex = NULL;
- return cond;
+ s_smx_process_t p; /* useful to initialize sleeping swag */
+
+ smx_mutex_t mutex = xbt_new0(s_smx_mutex_t, 1);
+ mutex->locked = 0;
+ mutex->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
+ return mutex;
}
-void SIMIX_cond_signal(smx_cond_t cond)
+/**
+ * \brief Handle mutex lock request
+ * \param req The request
+ */
+void SIMIX_pre_mutex_lock(smx_req_t req)
+{
+ /* FIXME: check where to validate the arguments */
+ smx_action_t sync_act = NULL;
+ smx_mutex_t mutex = req->mutex_lock.mutex;
+ smx_process_t process = req->issuer;
+
+ if (mutex->locked) {
+ /* FIXME: check if the host is active ? */
+ /* Somebody using the mutex, use a synchro action to get host failures */
+ sync_act = SIMIX_synchro_wait(process->smx_host, -1);
+ xbt_fifo_push(sync_act->request_list, req);
+ req->issuer->waiting_action = sync_act;
+ xbt_swag_insert(req->issuer, mutex->sleeping);
+ } else {
+ /* mutex free */
+ mutex->locked = 1;
+ mutex->owner = req->issuer;
+ SIMIX_request_answer(req);
+ }
+}
+
+/**
+ * \brief Tries to lock a mutex.
+ *
+ * Tries to lock a mutex, return 1 if the mutex is unlocked, else 0.
+ * This function does not block and wait for the mutex to be unlocked.
+ * \param mutex The mutex
+ * \param issuer The process that tries to acquire the mutex
+ * \return 1 - mutex free, 0 - mutex used
+ */
+int SIMIX_mutex_trylock(smx_mutex_t mutex, smx_process_t issuer)
+{
+ if (mutex->locked)
+ return 0;
+
+ mutex->locked = 1;
+ mutex->owner = issuer;
+ return 1;
+}
+
+/**
+ * \brief Unlocks a mutex.
+ *
+ * Unlocks the mutex and gives it to a process waiting for it.
+ * If the unlocker is not the owner of the mutex nothing happens.
+ * If there are no process waiting, it sets the mutex as free.
+ * \param mutex The mutex
+ * \param issuer The process trying to unlock the mutex
+ */
+void SIMIX_mutex_unlock(smx_mutex_t mutex, smx_process_t issuer)
+{
+ smx_process_t p; /*process to wake up */
+
+ /* If the mutex is not owned by the issuer do nothing */
+ if (issuer != mutex->owner)
+ return;
+
+ if (xbt_swag_size(mutex->sleeping) > 0) {
+ p = xbt_swag_extract(mutex->sleeping);
+ SIMIX_synchro_destroy(p->waiting_action);
+ p->waiting_action = NULL;
+ mutex->owner = p;
+ SIMIX_request_answer(&p->request);
+ } else {
+ /* nobody to wake up */
+ mutex->locked = 0;
+ mutex->owner = NULL;
+ }
+}
+
+/**
+ * \brief Destroys a mutex.
+ *
+ * Destroys and frees the mutex's memory.
+ * \param mutex A mutex
+ */
+void SIMIX_mutex_destroy(smx_mutex_t mutex)
{
- xbt_assert0((cond != NULL), "Invalid parameters");
- smx_process_t proc = NULL;
+ if (mutex){
+ xbt_swag_free(mutex->sleeping);
+ xbt_free(mutex);
+ }
+}
- if (xbt_swag_size(cond->sleeping) >= 1) {
- proc = xbt_swag_extract(cond->sleeping);
- __SIMIX_process_unblock(proc);
- }
+/********************************* Condition **********************************/
- return;
+/**
+ * \brief Initialize a condition.
+ *
+ * Allocates and creates the data for the condition.
+ * It have to be called before the use of the condition.
+ * \return A condition
+ */
+smx_cond_t SIMIX_cond_init()
+{
+ s_smx_process_t p;
+ smx_cond_t cond = xbt_new0(s_smx_cond_t, 1);
+ cond->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
+ cond->mutex = NULL;
+ return cond;
}
-void SIMIX_cond_wait(smx_cond_t cond,smx_mutex_t mutex)
+/**
+ * \brief Handle condition waiting requests without timeouts
+ * \param The request
+ */
+void SIMIX_pre_cond_wait(smx_req_t req)
{
- /* call the function with timeout, with max_duration > 0
- * the process is blocked forever */
- SIMIX_cond_wait_timeout(cond, mutex, -1);
- return;
+ smx_process_t issuer = req->issuer;
+ smx_cond_t cond = req->cond_wait.cond;
+ smx_mutex_t mutex = req->cond_wait.mutex;
+
+ _SIMIX_cond_wait(cond, mutex, -1, issuer, req);
}
-void SIMIX_cond_wait_timeout(smx_cond_t cond,smx_mutex_t mutex, double max_duration)
+/**
+ * \brief Handle condition waiting requests with timeouts
+ * \param The request
+ */
+void SIMIX_pre_cond_wait_timeout(smx_req_t req)
{
- smx_process_t self = SIMIX_process_self();
+ smx_process_t issuer = req->issuer;
+ smx_cond_t cond = req->cond_wait_timeout.cond;
+ smx_mutex_t mutex = req->cond_wait_timeout.mutex;
+ double timeout = req->cond_wait_timeout.timeout;
+
+ _SIMIX_cond_wait(cond, mutex, timeout, issuer, req);
+}
- xbt_assert0((mutex != NULL), "Invalid parameters");
-
- /* process status */
- self->simdata->cond = cond;
- xbt_swag_insert(self, cond->sleeping);
- cond->mutex = mutex;
+static void _SIMIX_cond_wait(smx_cond_t cond, smx_mutex_t mutex, double timeout,
+ smx_process_t issuer, smx_req_t req)
+{
+ smx_action_t sync_act = NULL;
+
+ XBT_DEBUG("Wait condition %p", cond);
- SIMIX_mutex_unlock(mutex);
- /* if the max_duration < 0, blocks forever */
- if (max_duration >=0) {
- __SIMIX_process_block(max_duration);
- self->simdata->cond = NULL;
- }
- else {
- __SIMIX_process_block(-1);
- self->simdata->cond = NULL;
- }
- /* get the mutex again */
- SIMIX_mutex_lock(cond->mutex);
- return;
+ /* If there is a mutex unlock it */
+ /* FIXME: what happens if the issuer is not the owner of the mutex? */
+ if (mutex != NULL) {
+ cond->mutex = mutex;
+ SIMIX_mutex_unlock(mutex, issuer);
+ }
+
+ sync_act = SIMIX_synchro_wait(issuer->smx_host, timeout);
+ xbt_fifo_unshift(sync_act->request_list, req);
+ issuer->waiting_action = sync_act;
+ xbt_swag_insert(req->issuer, cond->sleeping);
}
+/**
+ * \brief Signalizes a condition.
+ *
+ * Signalizes a condition and wakes up a sleeping process.
+ * If there are no process sleeping, no action is done.
+ * \param cond A condition
+ */
+void SIMIX_cond_signal(smx_cond_t cond)
+{
+ smx_process_t proc = NULL;
+ smx_mutex_t mutex = NULL;
+ smx_req_t req = NULL;
+
+ XBT_DEBUG("Signal condition %p", cond);
+
+ /* If there are processes waiting for the condition choose one and try
+ to make it acquire the mutex */
+ if ((proc = xbt_swag_extract(cond->sleeping))) {
+
+ /* Destroy waiter's synchro action */
+ SIMIX_synchro_destroy(proc->waiting_action);
+ proc->waiting_action = NULL;
+
+ /* Now transform the cond wait request into a mutex lock one */
+ req = &proc->request;
+ if(req->call == REQ_COND_WAIT)
+ mutex = req->cond_wait.mutex;
+ else
+ mutex = req->cond_wait_timeout.mutex;
+
+ req->call = REQ_MUTEX_LOCK;
+ req->mutex_lock.mutex = mutex;
+
+ SIMIX_pre_mutex_lock(req);
+ }
+}
+/**
+ * \brief Broadcasts a condition.
+ *
+ * Signal ALL processes waiting on a condition.
+ * If there are no process waiting, no action is done.
+ * \param cond A condition
+ */
void SIMIX_cond_broadcast(smx_cond_t cond)
{
- xbt_assert0((cond != NULL), "Invalid parameters");
- smx_process_t proc = NULL;
- smx_process_t proc_next = NULL;
+ XBT_DEBUG("Broadcast condition %p", cond);
- xbt_swag_foreach_safe(proc,proc_next,cond->sleeping) {
- __SIMIX_process_unblock(proc);
- xbt_swag_remove(proc,cond->sleeping);
- }
+ /* Signal the condition until nobody is waiting on it */
+ while (xbt_swag_size(cond->sleeping)) {
+ SIMIX_cond_signal(cond);
+ }
+}
+
+/**
+ * \brief Destroys a contidion.
+ *
+ * Destroys and frees the condition's memory.
+ * \param cond A condition
+ */
+void SIMIX_cond_destroy(smx_cond_t cond)
+{
+ XBT_DEBUG("Destroy condition %p", cond);
- return;
+ if (cond != NULL) {
+ xbt_assert(xbt_swag_size(cond->sleeping) == 0,
+ "Cannot destroy conditional since someone is still using it");
+
+ xbt_swag_free(cond->sleeping);
+ xbt_free(cond);
+ }
}
-SIMIX_error_t SIMIX_cond_destroy(smx_cond_t cond)
+/******************************** Semaphores **********************************/
+#define SMX_SEM_NOLIMIT 99999
+/** @brief Initialize a semaphore */
+smx_sem_t SIMIX_sem_init(unsigned int value)
{
-
- if ( cond == NULL )
- return SIMIX_WARNING;
- else {
- xbt_assert0( (xbt_swag_size(cond->sleeping) > 0) &&
- (xbt_fifo_size(cond->actions) > 0), "Cannot destroy conditional");
+ s_smx_process_t p;
- xbt_swag_free(cond->sleeping);
- xbt_fifo_free(cond->actions);
- xbt_free(cond);
- return SIMIX_OK;
- }
+ smx_sem_t sem = xbt_new0(s_smx_sem_t, 1);
+ sem->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
+ sem->value = value;
+ return sem;
}
-void SIMIX_register_condition_to_action(smx_action_t action, smx_cond_t cond)
+/** @brief Destroys a semaphore */
+void SIMIX_sem_destroy(smx_sem_t sem)
{
- xbt_assert0( (action != NULL) && (cond != NULL), "Invalid parameters");
+ XBT_DEBUG("Destroy semaphore %p", sem);
+ if (sem != NULL) {
+ xbt_assert(xbt_swag_size(sem->sleeping) == 0,
+ "Cannot destroy semaphore since someone is still using it");
+ xbt_swag_free(sem->sleeping);
+ xbt_free(sem);
+ }
+}
- xbt_fifo_push(action->simdata->cond_list,cond);
+/** @brief release the semaphore
+ *
+ * Unlock a process waiting on the semaphore.
+ * If no one was blocked, the semaphore capacity is increased by 1.
+ */
+void SIMIX_sem_release(smx_sem_t sem)
+{
+ smx_process_t proc;
+
+ XBT_DEBUG("Sem release semaphore %p", sem);
+ if ((proc = xbt_swag_extract(sem->sleeping))) {
+ proc = xbt_swag_extract(sem->sleeping);
+ SIMIX_synchro_destroy(proc->waiting_action);
+ proc->waiting_action = NULL;
+ SIMIX_request_answer(&proc->request);
+ } else if (sem->value < SMX_SEM_NOLIMIT) {
+ sem->value++;
+ }
}
+/** @brief Returns true if acquiring this semaphore would block */
+XBT_INLINE int SIMIX_sem_would_block(smx_sem_t sem)
+{
+ return (sem->value <= 0);
+}
+/** @brief Returns the current capacity of the semaphore */
+int SIMIX_sem_get_capacity(smx_sem_t sem)
+{
+ return sem->value;
+}
+
+static void _SIMIX_sem_wait(smx_sem_t sem, double timeout, smx_process_t issuer,
+ smx_req_t req)
+{
+ smx_action_t sync_act = NULL;
+
+ XBT_DEBUG("Wait semaphore %p (timeout:%f)", sem, timeout);
+ if (sem->value <= 0) {
+ sync_act = SIMIX_synchro_wait(issuer->smx_host, timeout);
+ xbt_fifo_unshift(sync_act->request_list, req);
+ issuer->waiting_action = sync_act;
+ xbt_swag_insert(issuer, sem->sleeping);
+ } else {
+ sem->value--;
+ SIMIX_request_answer(req);
+ }
+}
+
+/**
+ * \brief Handle sem acquire requests without timeouts
+ */
+void SIMIX_pre_sem_acquire(smx_req_t req)
+{
+ _SIMIX_sem_wait(req->sem_acquire.sem, -1, req->issuer, req);
+}
+
+/**
+ * \brief Handle sem acquire requests with timeouts
+ */
+void SIMIX_pre_sem_acquire_timeout(smx_req_t req)
+{
+ _SIMIX_sem_wait(req->sem_acquire_timeout.sem,
+ req->sem_acquire_timeout.timeout, req->issuer, req);
+}