/* 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. */
-#include "private.h"
+#include "smx_private.h"
#include "xbt/log.h"
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_synchro, simix,
"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_simcall_t simcall);
+static void _SIMIX_sem_wait(smx_sem_t sem, double timeout, smx_process_t issuer,
+ smx_simcall_t simcall);
-/****************************** Synchronization *******************************/
+/***************************** Synchro action *********************************/
+static smx_action_t SIMIX_synchro_wait(smx_host_t smx_host, double timeout)
+{
+ XBT_IN("(%p, %f)",smx_host,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);
+ XBT_OUT();
+ return action;
+}
+
+void SIMIX_synchro_stop_waiting(smx_process_t process, smx_simcall_t simcall)
+{
+ XBT_IN("(%p, %p)",process,simcall);
+ switch (simcall->call) {
+
+ case SIMCALL_MUTEX_LOCK:
+ xbt_swag_remove(process, simcall->mutex_lock.mutex->sleeping);
+ break;
+
+ case SIMCALL_COND_WAIT:
+ xbt_swag_remove(process, simcall->cond_wait.cond->sleeping);
+ break;
+
+ case SIMCALL_COND_WAIT_TIMEOUT:
+ xbt_swag_remove(process, simcall->cond_wait_timeout.cond->sleeping);
+ break;
+
+ case SIMCALL_SEM_ACQUIRE:
+ xbt_swag_remove(process, simcall->sem_acquire.sem->sleeping);
+ break;
+
+ case SIMCALL_SEM_ACQUIRE_TIMEOUT:
+ xbt_swag_remove(process, simcall->sem_acquire_timeout.sem->sleeping);
+ break;
+
+ default:
+ THROW_IMPOSSIBLE;
+ }
+ XBT_OUT();
+}
+
+void SIMIX_synchro_destroy(smx_action_t action)
+{
+ XBT_IN("(%p)",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);
+ XBT_OUT();
+}
+
+void SIMIX_post_synchro(smx_action_t action)
+{
+ XBT_IN("(%p)",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);
+ XBT_OUT();
+}
+
+static void SIMIX_synchro_finish(smx_action_t action)
+{
+ XBT_IN("(%p)",action);
+ smx_simcall_t simcall = xbt_fifo_shift(action->simcalls);
+
+ switch (action->state) {
+
+ case SIMIX_SRC_TIMEOUT:
+ SMX_EXCEPTION(simcall->issuer, timeout_error, 0, "Synchro's wait timeout");
+ break;
+
+ case SIMIX_FAILED:
+ SMX_EXCEPTION(simcall->issuer, host_error, 0, "Host failed");
+ break;
+
+ default:
+ THROW_IMPOSSIBLE;
+ break;
+ }
+
+ SIMIX_synchro_stop_waiting(simcall->issuer, simcall);
+ SIMIX_synchro_destroy(action);
+ SIMIX_simcall_answer(simcall);
+ XBT_OUT();
+}
/*********************************** Mutex ************************************/
/**
* \brief Initialize a mutex.
*
- * Allocs and creates the data for the mutex. It have to be called before the utilisation of the mutex.
+ * Allocs and creates the data for the mutex.
* \return A mutex
*/
-smx_mutex_t SIMIX_mutex_init()
+smx_mutex_t SIMIX_mutex_init(void)
{
- smx_mutex_t m = xbt_new0(s_smx_mutex_t, 1);
+ XBT_IN("()");
s_smx_process_t p; /* useful to initialize sleeping swag */
- /* structures initialization */
- m->refcount = 0;
- m->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
- return m;
+
+ 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));
+ XBT_OUT();
+ return mutex;
}
/**
- * \brief Locks a mutex.
- *
- * Tries to lock a mutex, if the mutex isn't used yet, the process can continue its execution, else it'll be blocked here. You have to call #SIMIX_mutex_unlock to free the mutex.
- * \param mutex The mutex
+ * \brief Handles a mutex lock simcall.
+ * \param simcall the simcall
*/
-void SIMIX_mutex_lock(smx_mutex_t mutex)
+void SIMIX_pre_mutex_lock(smx_simcall_t simcall)
{
- smx_process_t self = SIMIX_process_self();
- xbt_assert0((mutex != NULL), "Invalid parameters");
-
-
- if (mutex->refcount) {
- /* somebody using the mutex, block */
- xbt_swag_insert(self, mutex->sleeping);
- self->mutex = mutex;
- /* wait for some process make the unlock and wake up me from mutex->sleeping */
- SIMIX_process_yield();
- self->mutex = NULL;
-
- /* verify if the process was suspended */
- while (self->suspended) {
- SIMIX_process_yield();
- }
-
- mutex->refcount = 1;
+ XBT_IN("(%p)",simcall);
+ /* FIXME: check where to validate the arguments */
+ smx_action_t sync_act = NULL;
+ smx_mutex_t mutex = simcall->mutex_lock.mutex;
+ smx_process_t process = simcall->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->simcalls, simcall);
+ simcall->issuer->waiting_action = sync_act;
+ xbt_swag_insert(simcall->issuer, mutex->sleeping);
} else {
/* mutex free */
- mutex->refcount = 1;
+ mutex->locked = 1;
+ mutex->owner = simcall->issuer;
+ SIMIX_simcall_answer(simcall);
}
- return;
+ XBT_OUT();
}
/**
* \brief Tries to lock a mutex.
*
- * Tries to lock a mutex, return 1 if the mutex is free, 0 else. This function does not block the process if the mutex is used.
+ * 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
*/
-XBT_INLINE int SIMIX_mutex_trylock(smx_mutex_t mutex)
+int SIMIX_mutex_trylock(smx_mutex_t mutex, smx_process_t issuer)
{
- xbt_assert0((mutex != NULL), "Invalid parameters");
-
- if (mutex->refcount)
- return 0;
- else {
- mutex->refcount = 1;
- return 1;
+ XBT_IN("(%p, %p)",mutex,issuer);
+ if (mutex->locked){
+ XBT_OUT();
+ return 0;
}
+
+ mutex->locked = 1;
+ mutex->owner = issuer;
+ XBT_OUT();
+ return 1;
}
/**
* \brief Unlocks a mutex.
*
- * Unlocks the mutex and wakes up a process blocked on it. If there are no process sleeping, only sets the mutex as free.
+ * 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)
+void SIMIX_mutex_unlock(smx_mutex_t mutex, smx_process_t issuer)
{
+ XBT_IN("(%p, %p)",mutex,issuer);
smx_process_t p; /*process to wake up */
- xbt_assert0((mutex != NULL), "Invalid parameters");
+ /* If the mutex is not owned by the issuer do nothing */
+ if (issuer != mutex->owner){
+ XBT_OUT();
+ return;
+ }
if (xbt_swag_size(mutex->sleeping) > 0) {
p = xbt_swag_extract(mutex->sleeping);
- mutex->refcount = 0;
- xbt_swag_insert(p, simix_global->process_to_run);
+ SIMIX_synchro_destroy(p->waiting_action);
+ p->waiting_action = NULL;
+ mutex->owner = p;
+ SIMIX_simcall_answer(&p->simcall);
} else {
/* nobody to wake up */
- mutex->refcount = 0;
+ mutex->locked = 0;
+ mutex->owner = NULL;
}
- return;
+ XBT_OUT();
}
/**
* Destroys and frees the mutex's memory.
* \param mutex A mutex
*/
-XBT_INLINE void SIMIX_mutex_destroy(smx_mutex_t mutex)
+void SIMIX_mutex_destroy(smx_mutex_t mutex)
{
- if (mutex == NULL)
- return;
- else {
+ XBT_IN("(%p)",mutex);
+ if (mutex){
xbt_swag_free(mutex->sleeping);
xbt_free(mutex);
- return;
}
+ XBT_OUT();
}
-/******************************** Conditional *********************************/
+/********************************* Condition **********************************/
/**
* \brief Initialize a condition.
*/
smx_cond_t SIMIX_cond_init()
{
- smx_cond_t cond = xbt_new0(s_smx_cond_t, 1);
+ XBT_IN("()");
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->actions = xbt_fifo_new();
cond->mutex = NULL;
+ XBT_OUT();
return cond;
}
/**
- * \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
+ * \brief Handle a condition waiting simcall without timeouts
+ * \param simcall the simcall
*/
-void SIMIX_cond_signal(smx_cond_t cond)
+void SIMIX_pre_cond_wait(smx_simcall_t simcall)
{
- smx_process_t proc = NULL;
- DEBUG1("Signal condition %p", cond);
- xbt_assert0((cond != NULL), "Invalid parameters");
-
-
- if (xbt_swag_size(cond->sleeping) >= 1) {
- proc = xbt_swag_extract(cond->sleeping);
- xbt_swag_insert(proc, simix_global->process_to_run);
- }
+ XBT_IN("(%p)",simcall);
+ smx_process_t issuer = simcall->issuer;
+ smx_cond_t cond = simcall->cond_wait.cond;
+ smx_mutex_t mutex = simcall->cond_wait.mutex;
- return;
+ _SIMIX_cond_wait(cond, mutex, -1, issuer, simcall);
+ XBT_OUT();
}
/**
- * \brief Waits on a condition.
- *
- * Blocks a process until the signal is called. This functions frees the mutex associated and locks it after its execution.
- * \param cond A condition
- * \param mutex A mutex
+ * \brief Handle a condition waiting simcall with timeouts
+ * \param simcall the simcall
*/
-void SIMIX_cond_wait(smx_cond_t cond, smx_mutex_t mutex)
+void SIMIX_pre_cond_wait_timeout(smx_simcall_t simcall)
{
- smx_action_t act_sleep;
-
- DEBUG1("Wait condition %p", cond);
-
- /* If there is a mutex unlock it */
- if(mutex != NULL){
- cond->mutex = mutex;
- SIMIX_mutex_unlock(mutex);
- }
-
- /* Always create an action null in case there is a host failure */
- act_sleep = SIMIX_action_sleep(SIMIX_host_self(), -1);
- SIMIX_action_set_name(act_sleep,bprintf("Wait condition %p", cond));
- SIMIX_process_self()->waiting_action = act_sleep;
- SIMIX_register_action_to_condition(act_sleep, cond);
- __SIMIX_cond_wait(cond);
- SIMIX_process_self()->waiting_action = NULL;
- SIMIX_unregister_action_to_condition(act_sleep, cond);
- SIMIX_action_destroy(act_sleep);
-
- /* get the mutex again if necessary */
- if(mutex != NULL)
- SIMIX_mutex_lock(cond->mutex);
-
- return;
+ XBT_IN("(%p)",simcall);
+ smx_process_t issuer = simcall->issuer;
+ smx_cond_t cond = simcall->cond_wait_timeout.cond;
+ smx_mutex_t mutex = simcall->cond_wait_timeout.mutex;
+ double timeout = simcall->cond_wait_timeout.timeout;
+
+ _SIMIX_cond_wait(cond, mutex, timeout, issuer, simcall);
+ XBT_OUT();
}
-XBT_INLINE xbt_fifo_t SIMIX_cond_get_actions(smx_cond_t cond)
-{
- xbt_assert0((cond != NULL), "Invalid parameters");
- return cond->actions;
-}
-void __SIMIX_cond_wait(smx_cond_t cond)
+static void _SIMIX_cond_wait(smx_cond_t cond, smx_mutex_t mutex, double timeout,
+ smx_process_t issuer, smx_simcall_t simcall)
{
- smx_process_t self = SIMIX_process_self();
- xbt_assert0((cond != NULL), "Invalid parameters");
+ XBT_IN("(%p, %p, %f, %p,%p)",cond,mutex,timeout,issuer,simcall);
+ smx_action_t sync_act = NULL;
- /* process status */
+ XBT_DEBUG("Wait condition %p", cond);
- self->cond = cond;
- xbt_swag_insert(self, cond->sleeping);
- SIMIX_process_yield();
- self->cond = NULL;
- while (self->suspended) {
- SIMIX_process_yield();
+ /* 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);
}
- return;
+
+ sync_act = SIMIX_synchro_wait(issuer->smx_host, timeout);
+ xbt_fifo_unshift(sync_act->simcalls, simcall);
+ issuer->waiting_action = sync_act;
+ xbt_swag_insert(simcall->issuer, cond->sleeping);
+ XBT_OUT();
}
/**
- * \brief Waits on a condition with timeout.
+ * \brief Signalizes a condition.
*
- * Same behavior of #SIMIX_cond_wait, but waits a maximum time and throws an timeout_error if it happens.
+ * Signalizes a condition and wakes up a sleeping process.
+ * If there are no process sleeping, no action is done.
* \param cond A condition
- * \param mutex A mutex
- * \param max_duration Timeout time
*/
-void SIMIX_cond_wait_timeout(smx_cond_t cond, smx_mutex_t mutex,
- double max_duration)
+void SIMIX_cond_signal(smx_cond_t cond)
{
- smx_action_t act_sleep;
+ XBT_IN("(%p)",cond);
+ smx_process_t proc = NULL;
+ smx_mutex_t mutex = NULL;
+ smx_simcall_t simcall = NULL;
- DEBUG1("Timed wait condition %p", cond);
+ XBT_DEBUG("Signal condition %p", cond);
- /* If there is a mutex unlock it */
- if(mutex != NULL){
- cond->mutex = mutex;
- SIMIX_mutex_unlock(mutex);
- }
+ /* 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))) {
- if (max_duration >= 0) {
- act_sleep = SIMIX_action_sleep(SIMIX_host_self(), max_duration);
- SIMIX_action_set_name(act_sleep,bprintf("Timed wait condition %p (max_duration:%f)", cond,max_duration));
- SIMIX_register_action_to_condition(act_sleep, cond);
- SIMIX_process_self()->waiting_action = act_sleep;
- __SIMIX_cond_wait(cond);
- SIMIX_process_self()->waiting_action = NULL;
- SIMIX_unregister_action_to_condition(act_sleep, cond);
- if (SIMIX_action_get_state(act_sleep) == SURF_ACTION_DONE) {
- SIMIX_action_destroy(act_sleep);
- THROW1(timeout_error, 0, "Condition timeout after %f",max_duration);
- } else {
- SIMIX_action_destroy(act_sleep);
- }
-
- } else
- SIMIX_cond_wait(cond,NULL);
-
- /* get the mutex again if necessary */
- if(mutex != NULL)
- SIMIX_mutex_lock(cond->mutex);
+ /* Destroy waiter's synchro action */
+ SIMIX_synchro_destroy(proc->waiting_action);
+ proc->waiting_action = NULL;
+
+ /* Now transform the cond wait simcall into a mutex lock one */
+ simcall = &proc->simcall;
+ if(simcall->call == SIMCALL_COND_WAIT)
+ mutex = simcall->cond_wait.mutex;
+ else
+ mutex = simcall->cond_wait_timeout.mutex;
+
+ simcall->call = SIMCALL_MUTEX_LOCK;
+ simcall->mutex_lock.mutex = mutex;
+
+ SIMIX_pre_mutex_lock(simcall);
+ }
+ XBT_OUT();
}
/**
* \brief Broadcasts a condition.
*
- * Signalizes a condition and wakes up ALL sleping process. If there are no process sleeping, no action is done.
+ * 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)
{
- smx_process_t proc = NULL;
- smx_process_t proc_next = NULL;
+ XBT_IN("(%p)",cond);
+ XBT_DEBUG("Broadcast condition %p", cond);
- xbt_assert0((cond != NULL), "Invalid parameters");
-
- DEBUG1("Broadcast condition %p", cond);
- xbt_swag_foreach_safe(proc, proc_next, cond->sleeping) {
- xbt_swag_remove(proc, cond->sleeping);
- xbt_swag_insert(proc, simix_global->process_to_run);
+ /* Signal the condition until nobody is waiting on it */
+ while (xbt_swag_size(cond->sleeping)) {
+ SIMIX_cond_signal(cond);
}
+ XBT_OUT();
}
/**
*/
void SIMIX_cond_destroy(smx_cond_t cond)
{
- DEBUG1("Destroy condition %p", cond);
- if (cond == NULL)
- return;
- else {
- xbt_fifo_item_t item = NULL;
- smx_action_t action = NULL;
-
- xbt_assert0(xbt_swag_size(cond->sleeping) == 0,
- "Cannot destroy conditional since someone is still using it");
- xbt_swag_free(cond->sleeping);
+ XBT_IN("(%p)",cond);
+ XBT_DEBUG("Destroy condition %p", cond);
- DEBUG1("%d actions registered", xbt_fifo_size(cond->actions));
- __SIMIX_cond_display_actions(cond);
- xbt_fifo_foreach(cond->actions, item, action, smx_action_t) {
- SIMIX_unregister_action_to_condition(action, cond);
- }
- __SIMIX_cond_display_actions(cond);
+ if (cond != NULL) {
+ xbt_assert(xbt_swag_size(cond->sleeping) == 0,
+ "Cannot destroy conditional since someone is still using it");
- xbt_fifo_free(cond->actions);
+ xbt_swag_free(cond->sleeping);
xbt_free(cond);
- return;
- }
-}
-
-void SIMIX_cond_display_info(smx_cond_t cond)
-{
- if (cond == NULL)
- return;
- else {
- smx_process_t process = NULL;
-
- INFO0("Blocked process on this condition:");
- xbt_swag_foreach(process, cond->sleeping) {
- INFO2("\t %s running on host %s", process->name,
- process->smx_host->name);
- }
}
+ XBT_OUT();
}
-/* ************************** Semaphores ************************************** */
+/******************************** Semaphores **********************************/
#define SMX_SEM_NOLIMIT 99999
/** @brief Initialize a semaphore */
-smx_sem_t SIMIX_sem_init(int capacity) {
- smx_sem_t sem = xbt_new0(s_smx_sem_t, 1);
+smx_sem_t SIMIX_sem_init(unsigned int value)
+{
+ XBT_IN("(%d)",value);
s_smx_process_t p;
+ smx_sem_t sem = xbt_new0(s_smx_sem_t, 1);
sem->sleeping = xbt_swag_new(xbt_swag_offset(p, synchro_hookup));
- sem->actions = xbt_fifo_new();
- sem->capacity = capacity;
+ sem->value = value;
+ XBT_OUT();
return sem;
}
+
/** @brief Destroys a semaphore */
-void SIMIX_sem_destroy(smx_sem_t sem) {
- smx_action_t action = NULL;
- DEBUG1("Destroy semaphore %p", sem);
- if (sem == NULL)
- return;
-
- xbt_assert0(xbt_swag_size(sem->sleeping) == 0,
- "Cannot destroy semaphore since someone is still using it");
- xbt_swag_free(sem->sleeping);
-
- DEBUG1("%d actions registered", xbt_fifo_size(sem->actions));
- while((action=xbt_fifo_pop(sem->actions)))
- SIMIX_unregister_action_to_semaphore(action, sem);
-
- xbt_fifo_free(sem->actions);
- xbt_free(sem);
+void SIMIX_sem_destroy(smx_sem_t sem)
+{
+ XBT_IN("(%p)",sem);
+ 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_OUT();
}
/** @brief release the semaphore
*
- * The first locked process on this semaphore is unlocked.
+ * 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) {
- DEBUG1("Sem release semaphore %p", sem);
- if (xbt_swag_size(sem->sleeping) >= 1) {
- smx_process_t proc = xbt_swag_extract(sem->sleeping);
- xbt_swag_insert(proc, simix_global->process_to_run);
- } else if (sem->capacity != SMX_SEM_NOLIMIT) {
- sem->capacity++;
- }
-}
-/** @brief make sure the semaphore will never be blocking again
- *
- * This function is not really in the semaphore spirit. It makes
- * sure that the semaphore will never be blocking anymore.
- *
- * Releasing and acquiring the semaphore after calling this
- * function is a noop. Such "broken" semaphores are useful to
- * implement something between condition variables (with broadcast)
- * and semaphore (with memory). It's like a semaphore signaled for ever.
- *
- * There is no way to reset the semaphore to a more regular state afterward.
- * */
-void SIMIX_sem_release_forever(smx_sem_t sem) {
- smx_process_t proc = NULL;
- smx_process_t proc_next = NULL;
-
- DEBUG1("Broadcast semaphore %p", sem);
- xbt_swag_foreach_safe(proc, proc_next, sem->sleeping) {
- xbt_swag_remove(proc, sem->sleeping);
- xbt_swag_insert(proc, simix_global->process_to_run);
- }
- sem->capacity = SMX_SEM_NOLIMIT;
-}
-
-/**
- * \brief Low level wait on a semaphore
- *
- * This function does not test the capacity of the semaphore and direcly locks
- * the calling process on the semaphore (until someone call SIMIX_sem_release()
- * on this semaphore). Do not call this function if you did not attach any action
- * to this semaphore to be awaken. Note also that you may miss host failure if you
- * do not attach a dummy action beforehand. SIMIX_sem_acquire does all these
- * things for you so you it may be preferable to use.
*/
-void SIMIX_sem_block_onto(smx_sem_t sem) {
- smx_process_t self = SIMIX_process_self();
-
- /* process status */
- self->sem = sem;
- xbt_swag_insert(self, sem->sleeping);
- SIMIX_process_yield();
- self->sem = NULL;
- while (self->suspended)
- SIMIX_process_yield();
+void SIMIX_sem_release(smx_sem_t sem)
+{
+ XBT_IN("(%p)",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_simcall_answer(&proc->simcall);
+ } else if (sem->value < SMX_SEM_NOLIMIT) {
+ sem->value++;
+ }
+ XBT_OUT();
}
/** @brief Returns true if acquiring this semaphore would block */
-XBT_INLINE int SIMIX_sem_would_block(smx_sem_t sem) {
- return (sem->capacity<=0);
+XBT_INLINE int SIMIX_sem_would_block(smx_sem_t sem)
+{
+ XBT_IN("(%p)",sem);
+ XBT_OUT();
+ return (sem->value <= 0);
}
-/** @brief Returns the current capacity of the semaphore
- *
- * If it's negative, that's the amount of processes locked on the semaphore
- */
-int SIMIX_sem_get_capacity(smx_sem_t sem){
- return sem->capacity;
+/** @brief Returns the current capacity of the semaphore */
+int SIMIX_sem_get_capacity(smx_sem_t sem)
+{
+ XBT_IN("(%p)",sem);
+ XBT_OUT();
+ return sem->value;
}
-/**
- * \brief Waits on a semaphore
- *
- * If the capacity>0, decrease the capacity.
- *
- * If capacity==0, locks the current process
- * until someone call SIMIX_sem_release() on this semaphore
- */
-void SIMIX_sem_acquire(smx_sem_t sem) {
- smx_action_t act_sleep;
-
- DEBUG1("Wait semaphore %p", sem);
-
- if (sem->capacity == SMX_SEM_NOLIMIT) {
- DEBUG1("semaphore %p wide open", sem);
- return; /* don't even decrease it if wide open */
- }
-
- /* If capacity sufficient, decrease it */
- if (sem->capacity>0) {
- DEBUG1("semaphore %p has enough capacity", sem);
- sem->capacity--;
- return;
+static void _SIMIX_sem_wait(smx_sem_t sem, double timeout, smx_process_t issuer,
+ smx_simcall_t simcall)
+{
+ XBT_IN("(%p, %f, %p, %p)",sem,timeout,issuer,simcall);
+ 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->simcalls, simcall);
+ issuer->waiting_action = sync_act;
+ xbt_swag_insert(issuer, sem->sleeping);
+ } else {
+ sem->value--;
+ SIMIX_simcall_answer(simcall);
}
-
- sem->capacity--;
- /* Always create an action null in case there is a host failure */
- act_sleep = SIMIX_action_sleep(SIMIX_host_self(), -1);
- SIMIX_action_set_name(act_sleep,bprintf("Locked in semaphore %p", sem));
- SIMIX_process_self()->waiting_action = act_sleep;
- SIMIX_register_action_to_semaphore(act_sleep, sem);
- SIMIX_sem_block_onto(sem);
- SIMIX_process_self()->waiting_action = NULL;
- SIMIX_unregister_action_to_semaphore(act_sleep, sem);
- SIMIX_action_destroy(act_sleep);
- DEBUG1("End of Wait on semaphore %p", sem);
- sem->capacity++;
+ XBT_OUT();
}
+
/**
- * \brief Tries to acquire a semaphore before a timeout
- *
- * Same behavior of #SIMIX_sem_acquire, but waits a maximum time and throws an timeout_error if it happens.
+ * \brief Handles a sem acquire simcall without timeout.
+ * \param simcall the simcall
*/
-void SIMIX_sem_acquire_timeout(smx_sem_t sem, double max_duration) {
- smx_action_t act_sleep;
-
- DEBUG2("Timed wait semaphore %p (timeout:%f)", sem,max_duration);
-
- if (sem->capacity == SMX_SEM_NOLIMIT)
- return; /* don't even decrease it if wide open */
-
- /* If capacity sufficient, decrease it */
- if (sem->capacity>0) {
- sem->capacity--;
- return;
- }
-
- if (max_duration >= 0) {
- sem->capacity--;
- act_sleep = SIMIX_action_sleep(SIMIX_host_self(), max_duration);
- SIMIX_action_set_name(act_sleep,bprintf("Timed wait semaphore %p (max_duration:%f)", sem,max_duration));
- SIMIX_register_action_to_semaphore(act_sleep, sem);
- SIMIX_process_self()->waiting_action = act_sleep;
- SIMIX_sem_block_onto(sem);
- SIMIX_process_self()->waiting_action = NULL;
- SIMIX_unregister_action_to_semaphore(act_sleep, sem);
- if (SIMIX_action_get_state(act_sleep) == SURF_ACTION_DONE) {
- SIMIX_action_destroy(act_sleep);
- THROW1(timeout_error, 0, "Semaphore acquire timeouted after %f",max_duration);
- } else {
- SIMIX_action_destroy(act_sleep);
- }
- sem->capacity++;
-
- } else
- SIMIX_sem_acquire(sem);
+void SIMIX_pre_sem_acquire(smx_simcall_t simcall)
+{
+ XBT_IN("(%p)",simcall);
+ _SIMIX_sem_wait(simcall->sem_acquire.sem, -1, simcall->issuer, simcall);
+ XBT_OUT();
}
+
/**
- * \brief Blocks on a set of semaphore
- *
- * If any of the semaphores has some more capacity, it gets decreased.
- * If not, blocks until the capacity of one of the semaphores becomes more friendly.
- *
- * \return the rank in the dynar of the semaphore which just got locked from the set
+ * \brief Handles a sem acquire simcall with timeout.
+ * \param simcall the simcall
*/
-unsigned int SIMIX_sem_acquire_any(xbt_dynar_t sems) {
- smx_sem_t sem;
- unsigned int counter,result=-1;
- smx_action_t act_sleep;
- smx_process_t self = SIMIX_process_self();
-
- xbt_assert0(xbt_dynar_length(sems),
- "I refuse to commit sucide by locking on an **empty** set of semaphores!!");
- DEBUG2("Wait on semaphore set %p (containing %ld semaphores)", sems,xbt_dynar_length(sems));
-
- xbt_dynar_foreach(sems,counter,sem) {
- if (!SIMIX_sem_would_block(sem)) {
- DEBUG1("Semaphore %p wouldn't block; get it without waiting",sem);
- SIMIX_sem_acquire(sem);
- return counter;
- }
- }
-
- /* Always create an action null in case there is a host failure */
- act_sleep = SIMIX_action_sleep(SIMIX_host_self(), -1);
- SIMIX_action_set_name(act_sleep,bprintf("Locked in semaphore %p", sem));
- self->waiting_action = act_sleep;
- SIMIX_register_action_to_semaphore(act_sleep, xbt_dynar_get_as(sems,0,smx_sem_t));
-
- /* Get listed as member of all the provided semaphores */
- self->sem = (smx_sem_t)sems; /* FIXME: we pass a pointer to dynar where a pointer to sem is expected...*/
- xbt_dynar_foreach(sems,counter,sem) {
- xbt_swag_insert(self, sem->sleeping);
- }
- SIMIX_process_yield();
- self->sem = NULL;
- while (self->suspended)
- SIMIX_process_yield();
-
- /* one of the semaphore unsuspended us -- great, let's search which one (and get out of the others) */
- xbt_dynar_foreach(sems,counter,sem) {
- if (xbt_swag_belongs(self,sem->sleeping))
- xbt_swag_remove(self,sem->sleeping);
- else {
- xbt_assert0(result==-1,"More than one semaphore unlocked us. Dunno what to do");
- result = counter;
- }
- }
- xbt_assert0(counter!=-1,"Cannot find which semaphore unlocked me!");
-
- /* Destroy the waiting action */
- self->waiting_action = NULL;
- SIMIX_unregister_action_to_semaphore(act_sleep, xbt_dynar_get_as(sems,0,smx_sem_t));
- SIMIX_action_destroy(act_sleep);
- return result;
+void SIMIX_pre_sem_acquire_timeout(smx_simcall_t simcall)
+{
+ XBT_IN("(%p)",simcall);
+ _SIMIX_sem_wait(simcall->sem_acquire_timeout.sem,
+ simcall->sem_acquire_timeout.timeout, simcall->issuer, simcall);
+ XBT_OUT();
}
