MPI3_DIAG_BUFFER_TYPE_TRACE
diag_buffer->type = MPI3_DIAG_BUFFER_TYPE_TRACE;
MPI3_DIAG_BUFFER_TYPE_TRACE);
hdb = mpi3mr_diag_buffer_for_type(mrioc, MPI3_DIAG_BUFFER_TYPE_TRACE);
MPI3_DIAG_BUFFER_TYPE_TRACE);