int MPI_Group_rank(MPI_Group group, int *rank)
{
OPAL_CR_NOOP_PROGRESS();
/* error checking */
if( MPI_PARAM_CHECK ) {
OMPI_ERR_INIT_FINALIZE(FUNC_NAME);
if( (MPI_GROUP_NULL == group) || ( NULL == group) ){
return OMPI_ERRHANDLER_INVOKE(MPI_COMM_WORLD, MPI_ERR_GROUP,
FUNC_NAME);
} else if (NULL == rank) {
return OMPI_ERRHANDLER_INVOKE(MPI_COMM_WORLD, MPI_ERR_ARG,
FUNC_NAME);
}
}
*rank=ompi_group_rank((ompi_group_t *)group);
return MPI_SUCCESS;
}
static int ompi_comm_allreduce_group_nb (int *inbuf, int *outbuf, int count,
struct ompi_op_t *op, ompi_comm_cid_context_t *cid_context,
ompi_request_t **req)
{
ompi_group_t *group = cid_context->newcomm->c_local_group;
const int group_size = ompi_group_size (group);
const int group_rank = ompi_group_rank (group);
ompi_communicator_t *comm = cid_context->comm;
int peers_group[3], *tmp, subreq_count = 0;
ompi_comm_allreduce_context_t *context;
ompi_comm_request_t *request;
ompi_request_t *subreq[3];
context = ompi_comm_allreduce_context_alloc (inbuf, outbuf, count, op, cid_context);
if (NULL == context) {
return OMPI_ERR_OUT_OF_RESOURCE;
}
tmp = context->tmpbuf = calloc (sizeof (int), count * 3);
if (NULL == context->tmpbuf) {
OBJ_RELEASE(context);
return OMPI_ERR_OUT_OF_RESOURCE;
}
request = ompi_comm_request_get ();
if (NULL == request) {
OBJ_RELEASE(context);
return OMPI_ERR_OUT_OF_RESOURCE;
}
request->context = &context->super;
/* basic recursive doubling allreduce on the group */
peers_group[0] = group_rank ? ((group_rank - 1) >> 1) : MPI_PROC_NULL;
peers_group[1] = (group_rank * 2 + 1) < group_size ? group_rank * 2 + 1: MPI_PROC_NULL;
peers_group[2] = (group_rank * 2 + 2) < group_size ? group_rank * 2 + 2 : MPI_PROC_NULL;
/* translate the ranks into the ranks of the parent communicator */
ompi_group_translate_ranks (group, 3, peers_group, comm->c_local_group, context->peers_comm);
/* reduce */
memmove (outbuf, inbuf, sizeof (int) * count);
for (int i = 0 ; i < 2 ; ++i) {
if (MPI_PROC_NULL != context->peers_comm[i + 1]) {
int rc = MCA_PML_CALL(irecv(tmp, count, MPI_INT, context->peers_comm[i + 1],
cid_context->pml_tag, comm, subreq + subreq_count++));
if (OMPI_SUCCESS != rc) {
ompi_comm_request_return (request);
return rc;
}
tmp += count;
}
}
ompi_comm_request_schedule_append (request, ompi_comm_allreduce_group_recv_complete, subreq, subreq_count);
ompi_comm_request_start (request);
*req = &request->super;
return OMPI_SUCCESS;
}
