- rank = smpi_mpi_comm_rank(comm);
-
- if (rank == root) {
- retval = smpi_create_request(buf, count, datatype, root, (root + 1) % comm->size, 0, comm, &request);
- request->forward = comm->size - 1;
- smpi_mpi_isend(request);
- } else {
- retval = smpi_create_request(buf, count, datatype, MPI_ANY_SOURCE, rank, 0, comm, &request);
- smpi_mpi_irecv(request);
- }
-
- smpi_mpi_wait(request, MPI_STATUS_IGNORE);
- xbt_mallocator_release(smpi_global->request_mallocator, request);
-
- smpi_bench_begin();
-
- return retval;
-}
-
-// FIXME: needs to return null in event of MPI_UNDEFINED color...
-// FIXME: seriously, this isn't pretty
-int SMPI_MPI_Comm_split(MPI_Comm comm, int color, int key, MPI_Comm *comm_out)
-{
- int retval = MPI_SUCCESS;
-
- int index, rank;
- smpi_mpi_request_t request;
- int colorkey[2];
- smpi_mpi_status_t status;
-
- smpi_bench_end();
-
- // FIXME: need to test parameters
-
- index = smpi_host_index();
- rank = comm->index_to_rank_map[index];
-
- if (0 == rank) {
- int *colors = xbt_new(int, comm->size);
- int *keys = xbt_new(int, comm->size);
- int i, j, k;
- smpi_mpi_communicator_t tempcomm = NULL;
- int colortmp;
- int keycount;
- int *keystmp = xbt_new(int, comm->size);
- int *rankstmp = xbt_new(int, comm->size);
- int tmpval;
- int indextmp;
-
- colors[0] = color;
- keys[0] = key;
-
- // FIXME: not efficient
- for (i = 1; i < comm->size; i++) {
- retval = smpi_create_request(colorkey, 2, MPI_INT, MPI_ANY_SOURCE, rank, MPI_ANY_TAG, comm, &request);
- smpi_mpi_irecv(request);
- smpi_mpi_wait(request, &status);
- xbt_mallocator_release(smpi_global->request_mallocator, request);
- colors[i] = colorkey[0];
- keys[i] = colorkey[1];
- }
-
- for (i = 0; i < comm->size; i++) {
- if (-1 == colors[i]) {
- continue;
- }
- colortmp = colors[i];
- keycount = 0;
- for (j = i; j < comm->size; j++) {
- if(colortmp == colors[j]) {
- colors[j] = -1;
- keystmp[keycount] = keys[j];
- rankstmp[keycount] = j;
- keycount++;
- }
- }
- if (0 < keycount) {
- // FIXME: yes, mock me, bubble sort...
- for (j = 0; j < keycount; j++) {
- for (k = keycount - 1; k > j; k--) {
- if (keystmp[k] < keystmp[k - 1]) {
- tmpval = keystmp[k];
- keystmp[k] = keystmp[k - 1];
- keystmp[k - 1] = tmpval;
-
- tmpval = rankstmp[k];
- rankstmp[k] = rankstmp[k - 1];
- rankstmp[k - 1] = tmpval;
- }
- }
- }
- tempcomm = xbt_new(s_smpi_mpi_communicator_t, 1);
- tempcomm->barrier_count = 0;
- tempcomm->barrier_mutex = SIMIX_mutex_init();
- tempcomm->barrier_cond = SIMIX_cond_init();
- tempcomm->rank_to_index_map = xbt_new(int, keycount);
- tempcomm->index_to_rank_map = xbt_new(int, smpi_global->host_count);
- for (j = 0; j < smpi_global->host_count; j++) {
- tempcomm->index_to_rank_map[j] = -1;
- }
- for (j = 0; j < keycount; j++) {
- indextmp = comm->rank_to_index_map[rankstmp[j]];
- tempcomm->rank_to_index_map[j] = indextmp;
- tempcomm->index_to_rank_map[indextmp] = j;
- }
- for (j = 0; j < keycount; j++) {
- retval = smpi_create_request(&j, 1, MPI_INT, 0, rankstmp[j], 0, comm, &request);
- request->data = tempcomm;
- smpi_mpi_isend(request);
- smpi_mpi_wait(request, &status);
- xbt_mallocator_release(smpi_global->request_mallocator, request);
- }
- }
- }
- } else {
- colorkey[0] = color;
- colorkey[1] = key;
- retval = smpi_create_request(colorkey, 2, MPI_INT, rank, 0, 0, comm, &request);
- smpi_mpi_isend(request);
- smpi_mpi_wait(request, &status);
- xbt_mallocator_release(smpi_global->request_mallocator, request);
- retval = smpi_create_request(colorkey, 1, MPI_INT, 0, rank, 0, comm, &request);
- smpi_mpi_irecv(request);
- smpi_mpi_wait(request, &status);
- *comm_out = request->data;
- }
-
- smpi_bench_begin();
-
- return retval;