+++ /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. */
-
-/*
- * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
- * University Research and Technology
- * Corporation. All rights reserved.
- * Copyright (c) 2004-2012 The University of Tennessee and The University
- * of Tennessee Research Foundation. All rights
- * reserved.
- * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
- * University of Stuttgart. All rights reserved.
- * Copyright (c) 2004-2005 The Regents of the University of California.
- * All rights reserved.
- * Copyright (c) 2008 Sun Microsystems, Inc. All rights reserved.
- * Copyright (c) 2009 University of Houston. All rights reserved.
- *
- * Additional copyrights may follow
- */
-
-#include "colls_private.h"
-#include "coll_tuned_topo.h"
-
-/*
- * Recursive-halving function is (*mostly*) copied from the BASIC coll module.
- * I have removed the part which handles "large" message sizes
- * (non-overlapping version of reduce_Scatter).
- */
-
-/* copied function (with appropriate renaming) starts here */
-
-/*
- * reduce_scatter_ompi_basic_recursivehalving
- *
- * Function: - reduce scatter implementation using recursive-halving
- * algorithm
- * Accepts: - same as MPI_Reduce_scatter()
- * Returns: - MPI_SUCCESS or error code
- * Limitation: - Works only for commutative operations.
- */
-int
-smpi_coll_tuned_reduce_scatter_ompi_basic_recursivehalving(void *sbuf,
- void *rbuf,
- int *rcounts,
- MPI_Datatype dtype,
- MPI_Op op,
- MPI_Comm comm
- )
-{
- int i, rank, size, count, err = MPI_SUCCESS;
- int tmp_size=1, remain = 0, tmp_rank, *disps = NULL;
- ptrdiff_t true_lb, true_extent, lb, extent, buf_size;
- char *recv_buf = NULL, *recv_buf_free = NULL;
- char *result_buf = NULL, *result_buf_free = NULL;
-
- /* Initialize */
- rank = comm->rank();
- size = comm->size();
-
- XBT_DEBUG("coll:tuned:reduce_scatter_ompi_basic_recursivehalving, rank %d", rank);
- if( (op!=MPI_OP_NULL && !op->is_commutative()))
- THROWF(arg_error,0, " reduce_scatter ompi_basic_recursivehalving can only be used for commutative operations! ");
-
- /* Find displacements and the like */
- disps = (int*) xbt_malloc(sizeof(int) * size);
- if (NULL == disps) return MPI_ERR_OTHER;
-
- disps[0] = 0;
- for (i = 0; i < (size - 1); ++i) {
- disps[i + 1] = disps[i] + rcounts[i];
- }
- count = disps[size - 1] + rcounts[size - 1];
-
- /* short cut the trivial case */
- if (0 == count) {
- xbt_free(disps);
- return MPI_SUCCESS;
- }
-
- /* get datatype information */
- dtype->extent(&lb, &extent);
- dtype->extent(&true_lb, &true_extent);
- buf_size = true_extent + (ptrdiff_t)(count - 1) * extent;
-
- /* Handle MPI_IN_PLACE */
- if (MPI_IN_PLACE == sbuf) {
- sbuf = rbuf;
- }
-
- /* Allocate temporary receive buffer. */
- recv_buf_free = (char*) smpi_get_tmp_recvbuffer(buf_size);
-
- recv_buf = recv_buf_free - lb;
- if (NULL == recv_buf_free) {
- err = MPI_ERR_OTHER;
- goto cleanup;
- }
-
- /* allocate temporary buffer for results */
- result_buf_free = (char*) smpi_get_tmp_sendbuffer(buf_size);
-
- result_buf = result_buf_free - lb;
-
- /* copy local buffer into the temporary results */
- err =Datatype::copy(sbuf, count, dtype, result_buf, count, dtype);
- if (MPI_SUCCESS != err) goto cleanup;
-
- /* figure out power of two mapping: grow until larger than
- comm size, then go back one, to get the largest power of
- two less than comm size */
- while (tmp_size <= size) tmp_size <<= 1;
- tmp_size >>= 1;
- remain = size - tmp_size;
-
- /* If comm size is not a power of two, have the first "remain"
- procs with an even rank send to rank + 1, leaving a power of
- two procs to do the rest of the algorithm */
- if (rank < 2 * remain) {
- if ((rank & 1) == 0) {
- Request::send(result_buf, count, dtype, rank + 1,
- COLL_TAG_REDUCE_SCATTER,
- comm);
- /* we don't participate from here on out */
- tmp_rank = -1;
- } else {
- Request::recv(recv_buf, count, dtype, rank - 1,
- COLL_TAG_REDUCE_SCATTER,
- comm, MPI_STATUS_IGNORE);
-
- /* integrate their results into our temp results */
- if(op!=MPI_OP_NULL) op->apply( recv_buf, result_buf, &count, dtype);
-
- /* adjust rank to be the bottom "remain" ranks */
- tmp_rank = rank / 2;
- }
- } else {
- /* just need to adjust rank to show that the bottom "even
- remain" ranks dropped out */
- tmp_rank = rank - remain;
- }
-
- /* For ranks not kicked out by the above code, perform the
- recursive halving */
- if (tmp_rank >= 0) {
- int *tmp_disps = NULL, *tmp_rcounts = NULL;
- int mask, send_index, recv_index, last_index;
-
- /* recalculate disps and rcounts to account for the
- special "remainder" processes that are no longer doing
- anything */
- tmp_rcounts = (int*) xbt_malloc(tmp_size * sizeof(int));
- if (NULL == tmp_rcounts) {
- err = MPI_ERR_OTHER;
- goto cleanup;
- }
- tmp_disps = (int*) xbt_malloc(tmp_size * sizeof(int));
- if (NULL == tmp_disps) {
- xbt_free(tmp_rcounts);
- err = MPI_ERR_OTHER;
- goto cleanup;
- }
-
- for (i = 0 ; i < tmp_size ; ++i) {
- if (i < remain) {
- /* need to include old neighbor as well */
- tmp_rcounts[i] = rcounts[i * 2 + 1] + rcounts[i * 2];
- } else {
- tmp_rcounts[i] = rcounts[i + remain];
- }
- }
-
- tmp_disps[0] = 0;
- for (i = 0; i < tmp_size - 1; ++i) {
- tmp_disps[i + 1] = tmp_disps[i] + tmp_rcounts[i];
- }
-
- /* do the recursive halving communication. Don't use the
- dimension information on the communicator because I
- think the information is invalidated by our "shrinking"
- of the communicator */
- mask = tmp_size >> 1;
- send_index = recv_index = 0;
- last_index = tmp_size;
- while (mask > 0) {
- int tmp_peer, peer, send_count, recv_count;
- MPI_Request request;
-
- tmp_peer = tmp_rank ^ mask;
- peer = (tmp_peer < remain) ? tmp_peer * 2 + 1 : tmp_peer + remain;
-
- /* figure out if we're sending, receiving, or both */
- send_count = recv_count = 0;
- if (tmp_rank < tmp_peer) {
- send_index = recv_index + mask;
- for (i = send_index ; i < last_index ; ++i) {
- send_count += tmp_rcounts[i];
- }
- for (i = recv_index ; i < send_index ; ++i) {
- recv_count += tmp_rcounts[i];
- }
- } else {
- recv_index = send_index + mask;
- for (i = send_index ; i < recv_index ; ++i) {
- send_count += tmp_rcounts[i];
- }
- for (i = recv_index ; i < last_index ; ++i) {
- recv_count += tmp_rcounts[i];
- }
- }
-
- /* actual data transfer. Send from result_buf,
- receive into recv_buf */
- if (send_count > 0 && recv_count != 0) {
- request=Request::irecv(recv_buf + (ptrdiff_t)tmp_disps[recv_index] * extent,
- recv_count, dtype, peer,
- COLL_TAG_REDUCE_SCATTER,
- comm);
- if (MPI_SUCCESS != err) {
- xbt_free(tmp_rcounts);
- xbt_free(tmp_disps);
- goto cleanup;
- }
- }
- if (recv_count > 0 && send_count != 0) {
- Request::send(result_buf + (ptrdiff_t)tmp_disps[send_index] * extent,
- send_count, dtype, peer,
- COLL_TAG_REDUCE_SCATTER,
- comm);
- if (MPI_SUCCESS != err) {
- xbt_free(tmp_rcounts);
- xbt_free(tmp_disps);
- goto cleanup;
- }
- }
- if (send_count > 0 && recv_count != 0) {
- Request::wait(&request, MPI_STATUS_IGNORE);
- }
-
- /* if we received something on this step, push it into
- the results buffer */
- if (recv_count > 0) {
- if(op!=MPI_OP_NULL) op->apply(
- recv_buf + (ptrdiff_t)tmp_disps[recv_index] * extent,
- result_buf + (ptrdiff_t)tmp_disps[recv_index] * extent,
- &recv_count, dtype);
- }
-
- /* update for next iteration */
- send_index = recv_index;
- last_index = recv_index + mask;
- mask >>= 1;
- }
-
- /* copy local results from results buffer into real receive buffer */
- if (0 != rcounts[rank]) {
- err = Datatype::copy(result_buf + disps[rank] * extent,
- rcounts[rank], dtype,
- rbuf, rcounts[rank], dtype);
- if (MPI_SUCCESS != err) {
- xbt_free(tmp_rcounts);
- xbt_free(tmp_disps);
- goto cleanup;
- }
- }
-
- xbt_free(tmp_rcounts);
- xbt_free(tmp_disps);
- }
-
- /* Now fix up the non-power of two case, by having the odd
- procs send the even procs the proper results */
- if (rank < (2 * remain)) {
- if ((rank & 1) == 0) {
- if (rcounts[rank]) {
- Request::recv(rbuf, rcounts[rank], dtype, rank + 1,
- COLL_TAG_REDUCE_SCATTER,
- comm, MPI_STATUS_IGNORE);
- }
- } else {
- if (rcounts[rank - 1]) {
- Request::send(result_buf + disps[rank - 1] * extent,
- rcounts[rank - 1], dtype, rank - 1,
- COLL_TAG_REDUCE_SCATTER,
- comm);
- }
- }
- }
-
- cleanup:
- if (NULL != disps) xbt_free(disps);
- if (NULL != recv_buf_free) smpi_free_tmp_buffer(recv_buf_free);
- if (NULL != result_buf_free) smpi_free_tmp_buffer(result_buf_free);
-
- return err;
-}
-
-/* copied function (with appropriate renaming) ends here */
-
-
-/*
- * smpi_coll_tuned_reduce_scatter_ompi_ring
- *
- * Function: Ring algorithm for reduce_scatter operation
- * Accepts: Same as MPI_Reduce_scatter()
- * Returns: MPI_SUCCESS or error code
- *
- * Description: Implements ring algorithm for reduce_scatter:
- * the block sizes defined in rcounts are exchanged and
- 8 updated until they reach proper destination.
- * Algorithm requires 2 * max(rcounts) extra buffering
- *
- * Limitations: The algorithm DOES NOT preserve order of operations so it
- * can be used only for commutative operations.
- * Example on 5 nodes:
- * Initial state
- * # 0 1 2 3 4
- * [00] [10] -> [20] [30] [40]
- * [01] [11] [21] -> [31] [41]
- * [02] [12] [22] [32] -> [42]
- * -> [03] [13] [23] [33] [43] --> ..
- * [04] -> [14] [24] [34] [44]
- *
- * COMPUTATION PHASE
- * Step 0: rank r sends block (r-1) to rank (r+1) and
- * receives block (r+1) from rank (r-1) [with wraparound].
- * # 0 1 2 3 4
- * [00] [10] [10+20] -> [30] [40]
- * [01] [11] [21] [21+31] -> [41]
- * -> [02] [12] [22] [32] [32+42] -->..
- * [43+03] -> [13] [23] [33] [43]
- * [04] [04+14] -> [24] [34] [44]
- *
- * Step 1:
- * # 0 1 2 3 4
- * [00] [10] [10+20] [10+20+30] -> [40]
- * -> [01] [11] [21] [21+31] [21+31+41] ->
- * [32+42+02] -> [12] [22] [32] [32+42]
- * [03] [43+03+13] -> [23] [33] [43]
- * [04] [04+14] [04+14+24] -> [34] [44]
- *
- * Step 2:
- * # 0 1 2 3 4
- * -> [00] [10] [10+20] [10+20+30] [10+20+30+40] ->
- * [21+31+41+01]-> [11] [21] [21+31] [21+31+41]
- * [32+42+02] [32+42+02+12]-> [22] [32] [32+42]
- * [03] [43+03+13] [43+03+13+23]-> [33] [43]
- * [04] [04+14] [04+14+24] [04+14+24+34] -> [44]
- *
- * Step 3:
- * # 0 1 2 3 4
- * [10+20+30+40+00] [10] [10+20] [10+20+30] [10+20+30+40]
- * [21+31+41+01] [21+31+41+01+11] [21] [21+31] [21+31+41]
- * [32+42+02] [32+42+02+12] [32+42+02+12+22] [32] [32+42]
- * [03] [43+03+13] [43+03+13+23] [43+03+13+23+33] [43]
- * [04] [04+14] [04+14+24] [04+14+24+34] [04+14+24+34+44]
- * DONE :)
- *
- */
-int
-smpi_coll_tuned_reduce_scatter_ompi_ring(void *sbuf, void *rbuf, int *rcounts,
- MPI_Datatype dtype,
- MPI_Op op,
- MPI_Comm comm
- )
-{
- int ret, line, rank, size, i, k, recv_from, send_to, total_count, max_block_count;
- int inbi, *displs = NULL;
- char *tmpsend = NULL, *tmprecv = NULL, *accumbuf = NULL, *accumbuf_free = NULL;
- char *inbuf_free[2] = {NULL, NULL}, *inbuf[2] = {NULL, NULL};
- ptrdiff_t true_lb, true_extent, lb, extent, max_real_segsize;
- MPI_Request reqs[2] = {NULL, NULL};
-
- size = comm->size();
- rank = comm->rank();
-
- XBT_DEBUG( "coll:tuned:reduce_scatter_ompi_ring rank %d, size %d",
- rank, size);
-
- /* Determine the maximum number of elements per node,
- corresponding block size, and displacements array.
- */
- displs = (int*) xbt_malloc(size * sizeof(int));
- if (NULL == displs) { ret = -1; line = __LINE__; goto error_hndl; }
- displs[0] = 0;
- total_count = rcounts[0];
- max_block_count = rcounts[0];
- for (i = 1; i < size; i++) {
- displs[i] = total_count;
- total_count += rcounts[i];
- if (max_block_count < rcounts[i]) max_block_count = rcounts[i];
- }
-
- /* Special case for size == 1 */
- if (1 == size) {
- if (MPI_IN_PLACE != sbuf) {
- ret = Datatype::copy((char*)sbuf, total_count, dtype, (char*)rbuf, total_count, dtype);
- if (ret < 0) { line = __LINE__; goto error_hndl; }
- }
- xbt_free(displs);
- return MPI_SUCCESS;
- }
-
- /* Allocate and initialize temporary buffers, we need:
- - a temporary buffer to perform reduction (size total_count) since
- rbuf can be of rcounts[rank] size.
- - up to two temporary buffers used for communication/computation overlap.
- */
- dtype->extent(&lb, &extent);
- dtype->extent(&true_lb, &true_extent);
-
- max_real_segsize = true_extent + (ptrdiff_t)(max_block_count - 1) * extent;
-
- accumbuf_free = (char*)smpi_get_tmp_recvbuffer(true_extent + (ptrdiff_t)(total_count - 1) * extent);
- if (NULL == accumbuf_free) { ret = -1; line = __LINE__; goto error_hndl; }
- accumbuf = accumbuf_free - lb;
-
- inbuf_free[0] = (char*)smpi_get_tmp_sendbuffer(max_real_segsize);
- if (NULL == inbuf_free[0]) { ret = -1; line = __LINE__; goto error_hndl; }
- inbuf[0] = inbuf_free[0] - lb;
- if (size > 2) {
- inbuf_free[1] = (char*)smpi_get_tmp_sendbuffer(max_real_segsize);
- if (NULL == inbuf_free[1]) { ret = -1; line = __LINE__; goto error_hndl; }
- inbuf[1] = inbuf_free[1] - lb;
- }
-
- /* Handle MPI_IN_PLACE for size > 1 */
- if (MPI_IN_PLACE == sbuf) {
- sbuf = rbuf;
- }
-
- ret = Datatype::copy((char*)sbuf, total_count, dtype, accumbuf, total_count, dtype);
- if (ret < 0) { line = __LINE__; goto error_hndl; }
-
- /* Computation loop */
-
- /*
- For each of the remote nodes:
- - post irecv for block (r-2) from (r-1) with wrap around
- - send block (r-1) to (r+1)
- - in loop for every step k = 2 .. n
- - post irecv for block (r - 1 + n - k) % n
- - wait on block (r + n - k) % n to arrive
- - compute on block (r + n - k ) % n
- - send block (r + n - k) % n
- - wait on block (r)
- - compute on block (r)
- - copy block (r) to rbuf
- Note that we must be careful when computing the begining of buffers and
- for send operations and computation we must compute the exact block size.
- */
- send_to = (rank + 1) % size;
- recv_from = (rank + size - 1) % size;
-
- inbi = 0;
- /* Initialize first receive from the neighbor on the left */
- reqs[inbi]=Request::irecv(inbuf[inbi], max_block_count, dtype, recv_from,
- COLL_TAG_REDUCE_SCATTER, comm
- );
- tmpsend = accumbuf + (ptrdiff_t)displs[recv_from] * extent;
- Request::send(tmpsend, rcounts[recv_from], dtype, send_to,
- COLL_TAG_REDUCE_SCATTER,
- comm);
-
- for (k = 2; k < size; k++) {
- const int prevblock = (rank + size - k) % size;
-
- inbi = inbi ^ 0x1;
-
- /* Post irecv for the current block */
- reqs[inbi]=Request::irecv(inbuf[inbi], max_block_count, dtype, recv_from,
- COLL_TAG_REDUCE_SCATTER, comm
- );
-
- /* Wait on previous block to arrive */
- Request::wait(&reqs[inbi ^ 0x1], MPI_STATUS_IGNORE);
-
- /* Apply operation on previous block: result goes to rbuf
- rbuf[prevblock] = inbuf[inbi ^ 0x1] (op) rbuf[prevblock]
- */
- tmprecv = accumbuf + (ptrdiff_t)displs[prevblock] * extent;
- if(op!=MPI_OP_NULL) op->apply( inbuf[inbi ^ 0x1], tmprecv, &(rcounts[prevblock]), dtype);
-
- /* send previous block to send_to */
- Request::send(tmprecv, rcounts[prevblock], dtype, send_to,
- COLL_TAG_REDUCE_SCATTER,
- comm);
- }
-
- /* Wait on the last block to arrive */
- Request::wait(&reqs[inbi], MPI_STATUS_IGNORE);
-
- /* Apply operation on the last block (my block)
- rbuf[rank] = inbuf[inbi] (op) rbuf[rank] */
- tmprecv = accumbuf + (ptrdiff_t)displs[rank] * extent;
- if(op!=MPI_OP_NULL) op->apply( inbuf[inbi], tmprecv, &(rcounts[rank]), dtype);
-
- /* Copy result from tmprecv to rbuf */
- ret = Datatype::copy(tmprecv, rcounts[rank], dtype, (char*)rbuf, rcounts[rank], dtype);
- if (ret < 0) { line = __LINE__; goto error_hndl; }
-
- if (NULL != displs) xbt_free(displs);
- if (NULL != accumbuf_free) smpi_free_tmp_buffer(accumbuf_free);
- if (NULL != inbuf_free[0]) smpi_free_tmp_buffer(inbuf_free[0]);
- if (NULL != inbuf_free[1]) smpi_free_tmp_buffer(inbuf_free[1]);
-
- return MPI_SUCCESS;
-
- error_hndl:
- XBT_DEBUG( "%s:%4d\tRank %d Error occurred %d\n",
- __FILE__, line, rank, ret);
- if (NULL != displs) xbt_free(displs);
- if (NULL != accumbuf_free) smpi_free_tmp_buffer(accumbuf_free);
- if (NULL != inbuf_free[0]) smpi_free_tmp_buffer(inbuf_free[0]);
- if (NULL != inbuf_free[1]) smpi_free_tmp_buffer(inbuf_free[1]);
- return ret;
-}
-
