****************************************************************************/
int
-smpi_coll_tuned_alltoall_ring_light_barrier(void * send_buff, int send_count,
- MPI_Datatype send_type, void * recv_buff,
- int recv_count, MPI_Datatype recv_type,
- MPI_Comm comm)
+smpi_coll_tuned_alltoall_ring_light_barrier(void *send_buff, int send_count,
+ MPI_Datatype send_type,
+ void *recv_buff, int recv_count,
+ MPI_Datatype recv_type,
+ MPI_Comm comm)
{
MPI_Aint send_chunk, recv_chunk;
MPI_Status s;
int i, src, dst, rank, num_procs, next_dst, next_src;
- int tag = 1, success = 1; /*, failure = 0;*/
+ int tag = 1;
char send_sync = 'a', recv_sync = 'b';
- char * send_ptr = (char *) send_buff;
- char * recv_ptr = (char *) recv_buff;
-
+ char *send_ptr = (char *) send_buff;
+ char *recv_ptr = (char *) recv_buff;
+
MPI_Comm_rank(comm, &rank);
MPI_Comm_size(comm, &num_procs);
MPI_Type_extent(send_type, &send_chunk);
recv_chunk *= recv_count;
MPI_Sendrecv(send_ptr + rank * send_chunk, send_count, send_type, rank, tag,
- recv_ptr + rank * recv_chunk, recv_count, recv_type, rank, tag,
- comm, &s);
+ recv_ptr + rank * recv_chunk, recv_count, recv_type, rank, tag,
+ comm, &s);
+
+ for (i = 1; i < num_procs; i++) {
+ src = (rank - i + num_procs) % num_procs;
+ dst = (rank + i) % num_procs;
+
+ MPI_Sendrecv(send_ptr + dst * send_chunk, send_count, send_type,
+ dst, tag, recv_ptr + src * recv_chunk, recv_count,
+ recv_type, src, tag, comm, &s);
- for (i = 1; i < num_procs; i++)
- {
- src = (rank - i + num_procs) % num_procs;
- dst = (rank + i) % num_procs;
-
- MPI_Sendrecv(send_ptr + dst * send_chunk, send_count, send_type,
- dst, tag, recv_ptr + src * recv_chunk, recv_count,
- recv_type, src, tag, comm, &s);
+ if ((i + 1) < num_procs) {
+ next_src = (rank - (i + 1) + num_procs) % num_procs;
+ next_dst = (rank + (i + 1) + num_procs) % num_procs;
+ MPI_Sendrecv(&send_sync, 1, MPI_CHAR, next_src, tag,
+ &recv_sync, 1, MPI_CHAR, next_dst, tag, comm, &s);
- if ((i + 1) < num_procs)
- {
- next_src = (rank - (i + 1) + num_procs) % num_procs;
- next_dst = (rank + (i + 1) + num_procs) % num_procs;
- MPI_Sendrecv(&send_sync, 1, MPI_CHAR, next_src, tag,
- &recv_sync, 1, MPI_CHAR, next_dst, tag,
- comm, &s);
-
- }
}
+ }
- return success;
+ return MPI_SUCCESS;
}