+++ /dev/null
-/* 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"
-
-/*****************************************************************************
-
-Copyright (c) 2006, Ahmad Faraj & Xin Yuan,
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
-
- * Redistributions of source code must retain the above copyright notice,
- this list of conditions and the following disclaimer.
-
- * Redistributions in binary form must reproduce the above copyright notice,
- this list of conditions and the following disclaimer in the documentation
- and/or other materials provided with the distribution.
-
- * Neither the name of the Florida State University nor the names of its
- contributors may be used to endorse or promote products derived from this
- software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
-ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
-(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
-ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
- *************************************************************************
- * Any results obtained from executing this software require the *
- * acknowledgment and citation of the software and its owners. *
- * The full citation is given below: *
- * *
- * A. Faraj and X. Yuan. "Automatic Generation and Tuning of MPI *
- * Collective Communication Routines." The 19th ACM International *
- * Conference on Supercomputing (ICS), Cambridge, Massachusetts, *
- * June 20-22, 2005. *
- *************************************************************************
-
-*****************************************************************************/
-
-/*****************************************************************************
-
- * Function: bcast_scatter_LR_allgather
-
- * Return: int
-
- * Inputs:
- buff: send input buffer
- count: number of elements to send
- data_type: data type of elements being sent
- root: source of data
- comm: communicator
-
- * Descrp: broadcasts using a scatter followed by LR allgather.
-
- * Auther: MPIH / modified by Ahmad Faraj
-
- ****************************************************************************/
-int
-smpi_coll_tuned_bcast_scatter_LR_allgather(void *buff, int count,
- MPI_Datatype data_type, int root,
- MPI_Comm comm)
-{
- MPI_Aint extent;
- MPI_Status status;
- int i, src, dst, rank, num_procs;
- int mask, relative_rank, curr_size, recv_size, send_size, nbytes;
- int scatter_size, left, right, next_src, *recv_counts, *disps;
- int tag = COLL_TAG_BCAST;
-
- rank = smpi_comm_rank(comm);
- num_procs = smpi_comm_size(comm);
- extent = smpi_datatype_get_extent(data_type);
-
-
- nbytes = extent * count;
- scatter_size = (nbytes + num_procs - 1) / num_procs; // ceiling division
- curr_size = (rank == root) ? nbytes : 0; // root starts with all the data
- relative_rank = (rank >= root) ? rank - root : rank - root + num_procs;
-
- mask = 0x1;
- while (mask < num_procs) {
- if (relative_rank & mask) {
- src = rank - mask;
- if (src < 0)
- src += num_procs;
- recv_size = nbytes - relative_rank * scatter_size;
- // recv_size is larger than what might actually be sent by the
- // sender. We don't need compute the exact value because MPI
- // allows you to post a larger recv.
- if (recv_size <= 0)
- curr_size = 0; // this process doesn't receive any data
- // because of uneven division
- else {
- smpi_mpi_recv((char *) buff + relative_rank * scatter_size, recv_size,
- MPI_BYTE, src, tag, comm, &status);
- curr_size = smpi_mpi_get_count(&status, MPI_BYTE);
- }
- break;
- }
- mask <<= 1;
- }
-
- // This process is responsible for all processes that have bits
- // set from the LSB upto (but not including) mask. Because of
- // the "not including", we start by shifting mask back down
- // one.
-
- mask >>= 1;
- while (mask > 0) {
- if (relative_rank + mask < num_procs) {
- send_size = curr_size - scatter_size * mask;
- // mask is also the size of this process's subtree
-
- if (send_size > 0) {
- dst = rank + mask;
- if (dst >= num_procs)
- dst -= num_procs;
- smpi_mpi_send((char *) buff + scatter_size * (relative_rank + mask),
- send_size, MPI_BYTE, dst, tag, comm);
-
- curr_size -= send_size;
- }
- }
- mask >>= 1;
- }
-
- // done scatter now do allgather
- recv_counts = (int *) xbt_malloc(sizeof(int) * num_procs);
- disps = (int *) xbt_malloc(sizeof(int) * num_procs);
-
- for (i = 0; i < num_procs; i++) {
- recv_counts[i] = nbytes - i * scatter_size;
- if (recv_counts[i] > scatter_size)
- recv_counts[i] = scatter_size;
- if (recv_counts[i] < 0)
- recv_counts[i] = 0;
- }
-
- disps[0] = 0;
- for (i = 1; i < num_procs; i++)
- disps[i] = disps[i - 1] + recv_counts[i - 1];
-
- left = (num_procs + rank - 1) % num_procs;
- right = (rank + 1) % num_procs;
-
- src = rank;
- next_src = left;
-
- for (i = 1; i < num_procs; i++) {
- smpi_mpi_sendrecv((char *) buff + disps[(src - root + num_procs) % num_procs],
- recv_counts[(src - root + num_procs) % num_procs],
- MPI_BYTE, right, tag,
- (char *) buff +
- disps[(next_src - root + num_procs) % num_procs],
- recv_counts[(next_src - root + num_procs) % num_procs],
- MPI_BYTE, left, tag, comm, &status);
- src = next_src;
- next_src = (num_procs + next_src - 1) % num_procs;
- }
-
-
- free(recv_counts);
- free(disps);
-
- return MPI_SUCCESS;
-}
