1 /* Copyright (c) 2013-2023. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
7 #include "../colls_private.hpp"
8 #include "smpi_win.hpp"
10 /*****************************************************************************
12 * Function: alltoall_pair
17 send_buff: send input buffer
18 send_count: number of elements to send
19 send_type: data type of elements being sent
20 recv_buff: receive output buffer
21 recv_count: number of elements to received
22 recv_type: data type of elements being received
25 * Descrp: Function works when P is power of two. In each phase of P - 1
26 phases, nodes in pair communicate their data.
30 ****************************************************************************/
31 namespace simgrid::smpi {
32 int alltoall__pair_rma(const void *send_buff, int send_count, MPI_Datatype send_type,
33 void *recv_buff, int recv_count, MPI_Datatype recv_type,
37 MPI_Aint send_chunk, recv_chunk;
40 int i, dst, rank, num_procs;
42 char *send_ptr = (char *) send_buff;
45 num_procs = comm->size();
46 send_chunk = send_type->get_extent();
47 recv_chunk = recv_type->get_extent();
49 win = new Win(recv_buff, num_procs * recv_chunk * send_count, recv_chunk, nullptr, comm);
50 send_chunk *= send_count;
51 recv_chunk *= recv_count;
54 for (i = 0; i < num_procs; i++) {
56 win->put(send_ptr + dst * send_chunk, send_count, send_type, dst,
57 rank /* send_chunk*/, send_count, send_type);
60 simgrid::smpi::Win::del(win);
65 int alltoall__pair(const void *send_buff, int send_count,
66 MPI_Datatype send_type,
67 void *recv_buff, int recv_count,
68 MPI_Datatype recv_type, MPI_Comm comm)
71 MPI_Aint send_chunk, recv_chunk;
73 int i, src, dst, rank, num_procs;
74 int tag = COLL_TAG_ALLTOALL;
75 char *send_ptr = (char *) send_buff;
76 char *recv_ptr = (char *) recv_buff;
79 num_procs = comm->size();
81 if((num_procs&(num_procs-1)))
82 throw std::invalid_argument("alltoall pair algorithm can't be used with non power of two number of processes!");
84 send_chunk = send_type->get_extent();
85 recv_chunk = recv_type->get_extent();
87 send_chunk *= send_count;
88 recv_chunk *= recv_count;
90 for (i = 0; i < num_procs; i++) {
92 Request::sendrecv(send_ptr + dst * send_chunk, send_count, send_type, dst, tag, recv_ptr + src * recv_chunk,
93 recv_count, recv_type, src, tag, comm, &s);
98 } // namespace simgrid::smpi