1 /* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
4 * (C) 2003 by Argonne National Laboratory.
5 * See COPYRIGHT in top-level directory.
13 int main( int argc, char *argv[] )
16 int errors = 0, all_errors = 0;
20 MPI_Init(&argc, &argv);
21 MPI_Comm_rank(MPI_COMM_WORLD, &rank);
22 MPI_Comm_size(MPI_COMM_WORLD, &nproc);
25 if (rank == 0) printf("Error: must be run with two or more processes\n");
26 MPI_Abort(MPI_COMM_WORLD, 1);
29 /** Create using MPI_Win_create() **/
32 MPI_Alloc_mem(sizeof(int), MPI_INFO_NULL, &buf);
37 MPI_Win_create(buf, sizeof(int)*(rank == 0), 1, MPI_INFO_NULL, MPI_COMM_WORLD, &window);
39 /* Test flush of an empty epoch */
40 MPI_Win_lock(MPI_LOCK_SHARED, 0, 0, window);
41 MPI_Win_flush_all(window);
42 MPI_Win_unlock(0, window);
44 MPI_Barrier(MPI_COMM_WORLD);
46 /* Test third-party communication, through rank 0. */
47 MPI_Win_lock(MPI_LOCK_SHARED, 0, 0, window);
49 for (i = 0; i < ITER; i++) {
50 int val = -1, exp = -1;
52 /* Processes form a ring. Process 0 starts first, then passes a token
53 * to the right. Each process, in turn, performs third-party
54 * communication via process 0's window. */
56 MPI_Recv(NULL, 0, MPI_BYTE, rank-1, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
59 MPI_Get_accumulate(&rank, 1, MPI_INT, &val, 1, MPI_INT, 0, 0, 1, MPI_INT, MPI_REPLACE, window);
60 MPI_Win_flush(0, window);
62 exp = (rank + nproc-1) % nproc;
65 printf("%d - Got %d, expected %d\n", rank, val, exp);
70 MPI_Send(NULL, 0, MPI_BYTE, rank+1, 0, MPI_COMM_WORLD);
73 MPI_Barrier(MPI_COMM_WORLD);
76 MPI_Win_unlock(0, window);
78 MPI_Win_free(&window);
79 if (buf) MPI_Free_mem(buf);
81 MPI_Reduce(&errors, &all_errors, 1, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
83 if (rank == 0 && all_errors == 0)
84 printf(" No Errors\n");