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/*
* Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
* University Research and Technology
* Corporation. All rights reserved.
* Copyright (c) 2004-2005 The University of Tennessee and The University
* of Tennessee Research Foundation. All rights
* reserved.
* Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
* University of Stuttgart. All rights reserved.
* Copyright (c) 2004-2005 The Regents of the University of California.
* All rights reserved.
* Copyright (c) 2008 Cisco Systems, Inc. All rights reserved.
* $COPYRIGHT$
*
* Additional copyrights may follow
*
* $HEADER$
*/
#include "ompi_config.h"
#include "ompi/mca/topo/base/base.h"
#include "ompi/communicator/communicator.h"
#include "ompi/group/group.h"
#include "ompi/mca/topo/topo.h"
#include "mpi.h"
/*
* function - makes a new communicator to which topology information
* has been attached
*
* @param comm input communicator (handle)
* @param ndims number of dimensions of cartesian grid (integer)
* @param dims integer array of size ndims specifying the number of processes in
* each dimension
* @param periods logical array of size ndims specifying whether the grid is
* periodic (true) or not (false) in each dimension
* @param reorder ranking may be reordered (true) or not (false) (logical)
* @param comm_cart communicator with new cartesian topology (handle)
*
* Open MPI currently ignores the 'reorder' flag.
*
* @retval MPI_SUCCESS
*/
int mca_topo_base_cart_create (mca_topo_base_comm_t *topo_data,
int *proc_count,
ompi_proc_t **proc_pointers,
int *new_rank,
int ndims,
int *dims,
int *periods,
bool reorder) {
int nprocs;
int dim;
int i;
int *p;
int *coords = topo_data->mtc_coords;
int dummy_rank;
nprocs = 1;
p = topo_data->mtc_dims_or_index;
/* Calculate the number of processes in this grid */
for (i = 0; i < topo_data->mtc_ndims_or_nnodes; ++i, ++p) {
if(*p <= 0) {
return OMPI_ERROR;
}
nprocs *= *p;
}
/* check for the error condition */
if (*proc_count < nprocs) {
return MPI_ERR_DIMS;
}
/* check if we have to trim the list of processes */
if (nprocs < *proc_count) {
*proc_count = nprocs;
}
if (*new_rank > (nprocs-1)) {
/* sorry, but in our scheme this process is cut off */
*new_rank = MPI_UNDEFINED;
return MPI_SUCCESS;
}
/* Have to replace this with the actual function body itself */
p = topo_data->mtc_dims_or_index;
coords = topo_data->mtc_coords;
dummy_rank = *new_rank;
for (i=0;
(i < topo_data->mtc_ndims_or_nnodes && i < ndims);
++i, ++p) {
dim = *p;
nprocs /= dim;
*coords++ = dummy_rank / nprocs;
dummy_rank %= nprocs;
}
/* end here */
return MPI_SUCCESS;
}
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