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openmpi/ompi/communicator/comm_helpers.c
2016-11-22 15:03:20 -08:00

93 строки
3.2 KiB
C

/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil -*- */
/*
* Copyright (c) 2006 The Trustees of Indiana University and Indiana
* University Research and Technology
* Corporation. All rights reserved.
* Copyright (c) 2006 The Technical University of Chemnitz. All
* rights reserved.
* Copyright (c) 2014 Research Organization for Information Science
* and Technology (RIST). All rights reserved.
* Copyright (c) 2015 Los Alamos National Security, LLC. All rights
* reserved.
*
* Author(s): Torsten Hoefler <htor@cs.indiana.edu>
*
*/
#include "comm_helpers.h"
int ompi_comm_neighbors_count(MPI_Comm comm, int *indegree, int *outdegree, int *weighted) {
int res;
if (OMPI_COMM_IS_CART(comm)) {
int ndims;
res = MPI_Cartdim_get(comm, &ndims) ;
if (MPI_SUCCESS != res) {
return res;
}
/* outdegree is always 2*ndims because we need to iterate over empty buffers for MPI_PROC_NULL */
*outdegree = *indegree = 2*ndims;
*weighted = 0;
} else if (OMPI_COMM_IS_GRAPH(comm)) {
int rank, nneighbors;
rank = ompi_comm_rank ((ompi_communicator_t *) comm);
res = MPI_Graph_neighbors_count(comm, rank, &nneighbors);
if (MPI_SUCCESS != res) {
return res;
}
*outdegree = *indegree = nneighbors;
*weighted = 0;
} else if (OMPI_COMM_IS_DIST_GRAPH(comm)) {
res = MPI_Dist_graph_neighbors_count(comm, indegree, outdegree, weighted);
} else {
return MPI_ERR_ARG;
}
return MPI_SUCCESS;
}
int ompi_comm_neighbors(MPI_Comm comm, int maxindegree, int sources[], int sourceweights[], int maxoutdegree, int destinations[], int destweights[]) {
int res;
int index = 0;
int indeg, outdeg, wgtd;
res = ompi_comm_neighbors_count(comm, &indeg, &outdeg, &wgtd);
if (MPI_SUCCESS != res) {
return res;
}
if(indeg > maxindegree && outdeg > maxoutdegree) return MPI_ERR_TRUNCATE; /* we want to return *all* neighbors */
if (OMPI_COMM_IS_CART(comm)) {
int ndims, i, rpeer, speer;
res = MPI_Cartdim_get(comm, &ndims);
if (MPI_SUCCESS != res) {
return res;
}
for(i = 0; i<ndims; i++) {
res = MPI_Cart_shift(comm, i, 1, &rpeer, &speer);
if (MPI_SUCCESS != res) {
return res;
}
sources[index] = destinations[index] = rpeer; index++;
sources[index] = destinations[index] = speer; index++;
}
} else if (OMPI_COMM_IS_GRAPH(comm)) {
int rank = ompi_comm_rank ((ompi_communicator_t *) comm);
res = MPI_Graph_neighbors(comm, rank, maxindegree, sources);
if (MPI_SUCCESS != res) {
return res;
}
for(int i=0; i<maxindegree; i++) destinations[i] = sources[i];
} else if (OMPI_COMM_IS_DIST_GRAPH(comm)) {
res = MPI_Dist_graph_neighbors(comm, maxindegree, sources, sourceweights, maxoutdegree, destinations, destweights);
if (MPI_SUCCESS != res) {
return res;
}
} else {
return MPI_ERR_ARG;
}
return MPI_SUCCESS;
}