int tMPI_Thread_cond_broadcast(tMPI_Thread_cond_t *cond)
{
/* check whether the condition is initialized */
if (tMPI_Atomic_get( &(cond->initialized) ) == 0)
{
tMPI_Thread_cond_init_once(cond);
}
/* The condition variable is now guaranteed to be valid. */
#if 0
/* use this code once Vista is the minimum version required */
WakeAllConditionVariable( &(cond->cv) );
#else
EnterCriticalSection(&(cond->condp->wtr_lock));
/* check whether there are any waiters */
if (cond->condp->Nwaiters > 0)
{
cond->condp->Nrelease=cond->condp->Nwaiters;
cond->condp->cycle++;
if (!SetEvent(cond->condp->ev)) /* actually release the
waiting threads */
{
tMPI_Fatal_error(TMPI_FARGS,"Failed SetEvent, error code=%d",
GetLastError());
return -1;
}
}
LeaveCriticalSection(&(cond->condp->wtr_lock));
#endif
return 0;
}
int tMPI_Thread_cond_broadcast(tMPI_Thread_cond_t *cond)
{
int ret;
/* check whether the condition is initialized */
if (tMPI_Atomic_get( &(cond->initialized) ) == 0)
{
tMPI_Thread_cond_init_once(cond);
}
ret = pthread_cond_broadcast( &(cond->condp->cond) );
return ret;
}
int tMPI_Thread_cond_wait(tMPI_Thread_cond_t *cond, tMPI_Thread_mutex_t *mtx)
{
int ret;
/* check whether the condition is initialized */
if (tMPI_Atomic_get( &(cond->initialized) ) == 0)
{
tMPI_Thread_cond_init_once(cond);
}
/* the mutex must have been initialized because it should be locked here */
ret = pthread_cond_wait( &(cond->condp->cond), &(mtx->mutex->mtx) );
return ret;
}
int tMPI_Thread_cond_wait(tMPI_Thread_cond_t *cond, tMPI_Thread_mutex_t *mtx)
{
BOOL wait_done=FALSE;
BOOL last_waiter=FALSE;
int my_cycle;
/* check whether the condition is initialized */
if (tMPI_Atomic_get( &(cond->initialized) ) == 0)
{
tMPI_Thread_cond_init_once(cond);
}
/* the mutex must have been initialized because it should be locked here */
#if 0
/* use this code once Vista is the minimum version required */
ret=SleepConditionVariableCS (&(cond->cv), &(mtx->cs), INFINITE);
if (!ret)
{
tMPI_Fatal_error(TMPI_FARGS,"Failed wait for condition, error code=%d",
GetLastError());
return -1;
}
#else
/* serially increase waiter count */
EnterCriticalSection(&(cond->condp->wtr_lock));
cond->condp->Nwaiters++;
my_cycle = cond->condp->cycle;
LeaveCriticalSection(&(cond->condp->wtr_lock));
/* now it's safe to release the mutex from the fn call */
LeaveCriticalSection(&(mtx->mutex->cs));
/* Loop a wait until we found out we've waited for the right event.
Note that this loop is potentially a busy-wait loop in bad
circumstances (higher priority threads, for example). */
do
{
/* do the actual waiting */
if (WaitForSingleObject( cond->condp->ev, INFINITE )== WAIT_FAILED)
{
tMPI_Fatal_error(TMPI_FARGS,"Failed event reset, error code=%d",
GetLastError());
return -1;
}
/* serially check whether we got the right event. */
EnterCriticalSection(&(cond->condp->wtr_lock));
wait_done = (cond->condp->Nrelease > 0) &&
(cond->condp->cycle!=my_cycle);
LeaveCriticalSection(&(cond->condp->wtr_lock));
}
while(!wait_done);
/* We obtain the mutex from the function call */
EnterCriticalSection(&(mtx->mutex->cs));
/* we serially decrease the waiter count and release count */
EnterCriticalSection(&(cond->condp->wtr_lock));
cond->condp->Nwaiters--;
cond->condp->Nrelease--;
last_waiter=(cond->condp->Nrelease==0);
LeaveCriticalSection(&(cond->condp->wtr_lock));
/* manually release the event if everybody's done with it */
if (last_waiter)
{
if (!ResetEvent( cond->condp->ev ))
{
tMPI_Fatal_error(TMPI_FARGS,"Failed event reset, error code=%d",
GetLastError());
return -1;
}
}
#endif
return 0;
}
