-/* $Id$ */
-
-/* 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. */
* \param mutex The mutex
* \return 1 - mutex free, 0 - mutex used
*/
-int SIMIX_mutex_trylock(smx_mutex_t mutex)
+XBT_INLINE int SIMIX_mutex_trylock(smx_mutex_t mutex)
{
xbt_assert0((mutex != NULL), "Invalid parameters");
* Destroys and frees the mutex's memory.
* \param mutex A mutex
*/
-void SIMIX_mutex_destroy(smx_mutex_t mutex)
+XBT_INLINE void SIMIX_mutex_destroy(smx_mutex_t mutex)
{
if (mutex == NULL)
return;
return;
}
-xbt_fifo_t SIMIX_cond_get_actions(smx_cond_t cond)
+XBT_INLINE xbt_fifo_t SIMIX_cond_get_actions(smx_cond_t cond)
{
xbt_assert0((cond != NULL), "Invalid parameters");
return cond->actions;
}
/** @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_fifo_item_t item = NULL;
- smx_action_t action = NULL;
-
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));
- xbt_fifo_foreach(sem->actions, item, action, smx_action_t) {
+ while((action=xbt_fifo_pop(sem->actions)))
SIMIX_unregister_action_to_semaphore(action, sem);
- }
xbt_fifo_free(sem->actions);
xbt_free(sem);
* 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);
xbt_swag_remove(proc, sem->sleeping);
xbt_swag_insert(proc, simix_global->process_to_run);
}
+ sem->capacity = SMX_SEM_NOLIMIT;
}
-static inline void SIMIX_sem_block_onto(smx_sem_t sem) {
+/**
+ * \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 */
}
/** @brief Returns true if acquiring this semaphore would block */
-int SIMIX_sem_would_block(smx_sem_t sem) {
- return (sem->capacity>0);
+XBT_INLINE int SIMIX_sem_would_block(smx_sem_t sem) {
+ return (sem->capacity<=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;
}
/**
DEBUG1("Wait semaphore %p", sem);
- if (sem->capacity == SMX_SEM_NOLIMIT)
+ 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;
}
+ 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 = NULL;
SIMIX_unregister_action_to_semaphore(act_sleep, sem);
SIMIX_action_destroy(act_sleep);
+ DEBUG1("End of Wait on semaphore %p", sem);
+ sem->capacity++;
}
/**
* \brief Tries to acquire a semaphore before a timeout
}
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);
} else {
SIMIX_action_destroy(act_sleep);
}
+ sem->capacity++;
} else
SIMIX_sem_acquire(sem);
}
+/**
+ * \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
+ */
+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;
+}
