//MUST PROVIDE LOCKED MUTEX!
int mesa_cond_wait(mesa_cond_t* cond, int mutex_id)
{
printf(1,"%d | [%s] start \n",kthread_id(), __FUNCTION__);
cond->numOfThreadsWaiting++;
//releasing given mutex
if( kthread_mutex_unlock(mutex_id) < 0){
printf(1,"%d | [%s] failed, unlocking of given mutex %d failed \n",kthread_id(), __FUNCTION__, mutex_id);
return -1;
}
//waiting till signaled
if( kthread_mutex_lock(cond->inner_mutex_id) < 0){
printf(1,"%d | [%s] failed, locking of inner mutex %d after signaled failed \n",kthread_id(), __FUNCTION__, cond->inner_mutex_id);
return -1;
}
//taking back given mutex
if( kthread_mutex_lock(mutex_id) < 0){
printf(1,"%d | [%s] failed, locking of mutex %d after signaled failed \n",kthread_id(), __FUNCTION__, mutex_id);
return -1;
}
cond->numOfThreadsWaiting--;
printf(1,"%d | [%s] success \n",kthread_id(), __FUNCTION__);
return 0;
}
void * thread1 (void){
printf(1, "I went to sleep %d\n", kthread_id());
kthread_mutex_lock(lock);
kthread_cond_wait(cond, lock);
printf(1, "im came alive!! %d\n", kthread_id());
kthread_mutex_unlock(lock);
kthread_exit();
return (void *) 0;
}
//got here with mutex_id locked!
int mesa_cond_signal(mesa_cond_t* cond)
{
printf(1,"%d | [%s] start \n",kthread_id(), __FUNCTION__);
if( cond->numOfThreadsWaiting>0 && kthread_mutex_unlock(cond->inner_mutex_id) < 0){
printf(1,"%d | [%s] unlock failed, probably no one is waiting, locking again \n",kthread_id(), __FUNCTION__);
return -1;
}
printf(1,"%d | [%s] success \n",kthread_id(), __FUNCTION__);
return 0;
}
void * thread2 (void){
kthread_mutex_lock(lock);
printf(1,"I will wake him up!! %d", kthread_id());
kthread_cond_signal(cond);
kthread_exit();
return (void *) 0;
}
int mesa_cond_dealloc(mesa_cond_t* cond)
{
printf(1,"%d | [%s] start \n",kthread_id(), __FUNCTION__);
if(cond->numOfThreadsWaiting > 0){
printf(1,"%d | [%s] failed, there are %d threads waiting on this cv \n",kthread_id(), __FUNCTION__, cond->numOfThreadsWaiting);
return -1;
}
if(kthread_mutex_unlock(cond->inner_mutex_id) < 0){
printf(1,"%d | [%s] failed, unlocking of inner mutex %d failed \n",kthread_id(), __FUNCTION__, cond->inner_mutex_id);
return -1;
}
cond->inner_mutex_id = 0;
cond->numOfThreadsWaiting = 0;
free(cond);
printf(1,"%d | [%s] success \n",kthread_id(), __FUNCTION__);
return 0;
}
mesa_cond_t* mesa_cond_alloc()
{
printf(1,"%d | [%s] start \n",kthread_id(), __FUNCTION__);
mesa_cond_t* cv = malloc(sizeof(mesa_cond_t));
if(cv == 0){
printf(1,"%d | [%s] malloc cv failed \n",kthread_id(), __FUNCTION__);
return 0;
}
cv->inner_mutex_id = kthread_mutex_alloc();
cv->numOfThreadsWaiting = 0;
kthread_mutex_lock(cv->inner_mutex_id);
if(cv->inner_mutex_id < 0){
printf(1,"%d | [%s] inner mutex alloc failed \n",kthread_id(), __FUNCTION__);
return 0;
}
printf(1,"%d | [%s] success \n",kthread_id(), __FUNCTION__);
return cv;
}
void*
student(void){
int id;
id = kthread_id();
printf(1, "Student %d says: good morning!\n", id);
mesa_slots_monitor_takeslot(monitor);
printf(1, "Student %d says: slots left: %d\n", id, monitor->count);
printf(1, "Student %d says: bye bye!\n", id);
kthread_exit();
}
void*
grader(void){
int id;
id = kthread_id();
printf(1, "Grader %d says: I hate this job!\n", id);
while (mesa_slots_monitor_addslots(monitor, slotsPerRound) > -1){
printf(1, "Grader %d says: slots left: %d\n", id, monitor->count);
}
printf(1, "Grader %d says: f**k you BGU!\n", id);
kthread_exit();
}
