+/* Copyright (c) 2013-2014. The SimGrid Team.
+ * All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "../colls_private.h"
+/*****************************************************************************
+
+ * Function: alltoall_ring_mpi_barrier
+
+ * Return: int
+
+ * Inputs:
+ send_buff: send input buffer
+ send_count: number of elements to send
+ send_type: data type of elements being sent
+ recv_buff: receive output buffer
+ recv_count: number of elements to received
+ recv_type: data type of elements being received
+ comm: communicator
+
+ * Descrp: Function works in P - 1 steps. In step i, node j - i -> j -> j + i.
+ MPI barriers are added between each two phases.
+
+ * Auther: Ahmad Faraj
+
+ ****************************************************************************/
+int
+smpi_coll_tuned_alltoallv_ring_mpi_barrier(void *send_buff, int *send_counts, int *send_disps,
+ MPI_Datatype send_type,
+ void *recv_buff, int *recv_counts, int *recv_disps,
+ MPI_Datatype recv_type, MPI_Comm comm)
+{
+ MPI_Status s;
+ MPI_Aint send_chunk, recv_chunk;
+ int i, src, dst, rank, num_procs;
+ int tag = COLL_TAG_ALLTOALLV;
+
+ char *send_ptr = (char *) send_buff;
+ char *recv_ptr = (char *) recv_buff;
+
+ rank = comm->rank();
+ num_procs = comm->size();
+ send_chunk = send_type->get_extent();
+ recv_chunk = recv_type->get_extent();
+
+ for (i = 0; i < num_procs; i++) {
+ src = (rank - i + num_procs) % num_procs;
+ dst = (rank + i) % num_procs;
+
+ smpi_mpi_barrier(comm);
+ Request::sendrecv(send_ptr + send_disps[dst] * send_chunk, send_counts[dst], send_type, dst,
+ tag, recv_ptr + recv_disps[src] * recv_chunk, recv_counts[src], recv_type,
+ src, tag, comm, &s);
+ }
+
+ return MPI_SUCCESS;
+}