1 /* Copyright (c) 2009-2015. 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 /* This example should be instructive to learn about SMPI_SHARED_CALL */
14 static void* hash(char *str, uint64_t* ans)
18 printf("hashing !\n");
19 while ((c = *str++)!=0)
20 *ans = ((*ans << 5) + *ans) + c; /* hash * 33 + c */
24 int main(int argc, char *argv[])
26 MPI_Init(&argc, &argv);
28 MPI_Comm_rank(MPI_COMM_WORLD, &rank);
29 MPI_Comm_size(MPI_COMM_WORLD, &size);
30 //Let's Allocate a shared memory buffer
31 uint64_t* buf = SMPI_SHARED_MALLOC(sizeof(uint64_t));
32 //one writes data in it
37 MPI_Barrier(MPI_COMM_WORLD);
38 //everyone reads from it.
39 printf("[%d] The value in the shared buffer is: %" PRIu64"\n", rank, *buf);
41 MPI_Barrier(MPI_COMM_WORLD);
42 //Try SMPI_SHARED_CALL function, which should call hash only once and for all.
43 char *str = strdup("onceandforall");
45 SMPI_SHARED_CALL(hash,str,str,buf);
48 MPI_Barrier(MPI_COMM_WORLD);
50 printf("[%d] After change, the value in the shared buffer is: %" PRIu64"\n", rank, *buf);
52 SMPI_SHARED_FREE(buf);