1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
|
/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
#include "mpi.h"
#include <stdio.h>
#include <assert.h>
#include "mpitest.h"
/* This test divide 16 processes into 4 groups (nodes), each group
* creates a node_comm. Then roots of each node group creates a roots_comm.
*/
#define NP 16
#define PPN 4
#define N 4
int main(int argc, char *argv[])
{
int errs = 0;
int ret;
MPI_Session session;
MPI_Group world_group;
MPI_Comm comm;
MPI_Session_init(MPI_INFO_NULL, MPI_ERRORS_ARE_FATAL, &session);
MPI_Group_from_session_pset(session, "mpi://world", &world_group);
int world_rank, world_size;
MPI_Group_rank(world_group, &world_rank);
MPI_Group_size(world_group, &world_size);
if (world_size != NP) {
printf("This test require %d processes, world_size is %d.\n", NP, world_size);
goto fn_exit;
}
if (N * PPN != NP) {
printf("N(%d) x PPN(%d) != NP(%d)\n", N, PPN, NP);
goto fn_exit;
}
MPI_Group node_group, roots_group;
MPI_Comm node_comm, roots_comm;
int proc_list[NP];
int node_root = (world_rank / PPN) * PPN;
int is_root = (world_rank == node_root);
for (int i = 0; i < PPN; i++) {
proc_list[i] = node_root + i;
}
MPI_Group_incl(world_group, PPN, proc_list, &node_group);
MPI_Comm_create_from_group(node_group, "tag", MPI_INFO_NULL, MPI_ERRORS_ARE_FATAL, &node_comm);
if (is_root) {
for (int i = 0; i < N; i++) {
proc_list[i] = i * PPN;
}
MPI_Group_incl(world_group, N, proc_list, &roots_group);
MPI_Comm_create_from_group(roots_group, "tag", MPI_INFO_NULL, MPI_ERRORS_ARE_FATAL,
&roots_comm);
}
int node_sum, world_sum;
MPI_Reduce(&world_rank, &node_sum, 1, MPI_INT, MPI_SUM, 0, node_comm);
if (is_root) {
MPI_Reduce(&node_sum, &world_sum, 1, MPI_INT, MPI_SUM, 0, roots_comm);
}
if (world_rank == 0) {
int expect_sum = NP * (NP - 1) / 2;
if (world_sum != expect_sum) {
printf("Expect world_sum %d, got %d\n", expect_sum, world_sum);
} else {
printf("No Errors\n");
}
}
MPI_Comm_free(&node_comm);
MPI_Group_free(&node_group);
if (is_root) {
MPI_Comm_free(&roots_comm);
MPI_Group_free(&roots_group);
}
MPI_Group_free(&world_group);
MPI_Session_finalize(&session);
fn_exit:
return errs;
}
|
