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
|
/* Copyright (c) 2002-2025. 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. */
/* Simple test code that may deadlock:
Thread 1 locks mutex1 then mutex2 while thread 2 locks in reverse order.
Deadlock occurs when each thread get one mutex and then ask for the other one.
*/
#include "mpi.h"
#include <pthread.h>
#include <stdio.h>
pthread_mutex_t mutex1;
pthread_mutex_t mutex2;
static void* thread_fun1(void* val)
{
pthread_mutex_lock(&mutex1);
pthread_mutex_lock(&mutex2);
pthread_mutex_unlock(&mutex1);
pthread_mutex_unlock(&mutex2);
fprintf(stderr, "The thread %d is terminating.\n", *(int*)val);
return NULL;
}
static void* thread_fun2(void* val)
{
pthread_mutex_lock(&mutex2);
pthread_mutex_lock(&mutex1);
pthread_mutex_unlock(&mutex1);
pthread_mutex_unlock(&mutex2);
fprintf(stderr, "The thread %d is terminating.\n", *(int*)val);
return NULL;
}
int main(int argc, char* argv[])
{
/* Initialize Mpi Environment. */
int myrank, numprocs;
MPI_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &numprocs);
MPI_Comm_rank(MPI_COMM_WORLD, &myrank);
if (myrank == 0) {
pthread_mutex_init(&mutex1, NULL);
pthread_mutex_init(&mutex2, NULL);
int id[2] = {0, 1};
pthread_t thread1;
pthread_t thread2;
pthread_create(&thread1, NULL, thread_fun1, &id[0]);
pthread_create(&thread2, NULL, thread_fun2, &id[1]);
fprintf(stderr, "All threads are started.\n");
pthread_join(thread1, NULL);
pthread_join(thread2, NULL);
pthread_mutex_destroy(&mutex1);
pthread_mutex_destroy(&mutex2);
fprintf(stderr, "Rank0 is terminating.\n");
}
MPI_Finalize();
return 0;
}
|
