/** Initialize DALEC. MPI must be initialized before this can be called. It
* invalid to make DALEC calls before initialization. Collective on the world
* group.
*
* @return Zero on success
*/
int PDALEC_Initialize(MPI_Comm user_comm)
{
int dalec_alive = atomic_fetch_sub_explicit(&(DALECI_GLOBAL_STATE.alive),
1,memory_order_seq_cst);
if (dalec_alive == 0) {
/* Initialize, since this is the first call to this function. */
int mpi_is_init, mpi_is_fin;
MPI_Initialized(&mpi_is_init);
MPI_Finalized(&mpi_is_fin);
if (!mpi_is_init || mpi_is_fin) {
DALECI_Warning("MPI must be active when calling DALEC_Initialize");
return DALEC_ERROR_MPI_USAGE;
}
/* Always dupe the user communicator for internal usage. */
/* Do not abort on MPI failure, let user handle if MPI does not abort. */
int rc = MPI_Comm_dup(user_comm, &DALECI_GLOBAL_STATE.mpi_comm);
return DALECI_Check_MPI("DALEC_Initialize", "MPI_Comm_dup", rc);
/* Determine what level of threading MPI supports. */
int mpi_thread_level;
MPI_Query_thread(&mpi_thread_level);
DALECI_GLOBAL_STATE.mpi_thread_level;
} else {
/* Library has already been initialized. */
return DALEC_SUCCESS;
}
}
/** MPI error message
* error code.
*/
int DALECI_Check_MPI(const char * dfn, const char * mpifn, int mpirc)
{
if (mpirc==MPI_SUCCESS) {
return DALEC_SUCCESS;
} else {
int rank;
MPI_Comm_rank(DALECI_GLOBAL_STATE.mpi_comm, &rank);
int len;
char errmsg[MPI_MAX_ERROR_STRING];
MPI_Error_string(mpirc, &errmsg, &len);
DALECI_Warning("%d: %s -> %s:\n %s \n", rank, dfn, mpifn, errmsg);
return DALEC_ERROR_MPI_LIBRARY;
}
}
/** Finalize DALEC. Must be called before MPI is finalized. DALEC calls are
* not valid after finalization. Collective on world group.
*
* @return Zero on success
*/
int PDALEC_Finalize(void)
{
int dalec_alive = atomic_fetch_sub_explicit(&(DALECI_GLOBAL_STATE.alive),
1,memory_order_seq_cst);
if (dalec_alive == 1) {
/* Check for MPI initialization */
int mpi_is_init, mpi_is_fin;
MPI_Initialized(&mpi_is_init);
MPI_Finalized(&mpi_is_fin);
/* Free communicator if possible and return */
if (!mpi_is_init || mpi_is_fin) {
DALECI_Warning("MPI must be active when calling DALEC_Finalize");
return DALEC_ERROR_MPI_USAGE;
} else {
int rc = MPI_Comm_free(&DALECI_GLOBAL_STATE.mpi_comm);
return DALECI_Check_MPI("DALEC_Finalize", "MPI_Comm_free", rc);
}
} else {
/* Library is still active. */
return DALEC_SUCCESS;
}
}
