Add a sthread+MC example that deadlocks

[simgrid.git] / examples / sthread / pthread-mutex-simpledeadlock.c

diff --git a/examples/sthread/pthread-mutex-simpledeadlock.c b/examples/sthread/pthread-mutex-simpledeadlock.c
new file mode 100644 (file)
index 0000000..9025cd3
--- /dev/null
+++ b/examples/sthread/pthread-mutex-simpledeadlock.c
@@ -0,0 +1,53 @@
+/* Simple test code that may deadlock:
+
+   Thread 1 locks mutex1 then mutex2 while thread 2 locks in reverse order.
+   Deadlock occures when each thread get one mutex and then ask for the other one.
+ */
+
+#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[])
+{
+  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, (void*)&id[0]);
+  pthread_create(&thread2, NULL, thread_fun2, (void*)&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, "User's main is terminating.\n");
+  return 0;
+}