+ int ret;
+
+ ret = pthread_mutex_unlock(&rcu_copy_mutex);
+ if (ret) {
+ perror("Error in pthread mutex unlock");
+ exit(-1);
+ }
+}
+
+/*
+ * malloc/free are reusing memory areas too quickly, which does not let us
+ * test races appropriately. Use a large circular array for allocations.
+ * ARRAY_SIZE is larger than nr_writers, which insures we never run over our tail.
+ */
+#define ARRAY_SIZE (1048576 * nr_writers)
+#define ARRAY_POISON 0xDEADBEEF
+static int array_index;
+static struct test_array *test_array;
+
+static struct test_array *test_array_alloc(void)
+{
+ struct test_array *ret;
+ int index;
+
+ rcu_copy_mutex_lock();
+ index = array_index % ARRAY_SIZE;
+ assert(test_array[index].a == ARRAY_POISON ||
+ test_array[index].a == 0);
+ ret = &test_array[index];
+ array_index++;
+ if (array_index == ARRAY_SIZE)
+ array_index = 0;
+ rcu_copy_mutex_unlock();
+ return ret;
+}
+
+static void test_array_free(struct test_array *ptr)
+{
+ if (!ptr)
+ return;
+ rcu_copy_mutex_lock();
+ ptr->a = ARRAY_POISON;
+ rcu_copy_mutex_unlock();
+}
+
+void *thr_reader(void *_count)
+{
+ unsigned long long *count = _count;
+ struct test_array *local_ptr;
+
+ printf("thread_begin %s, thread id : %lx, tid %lu\n",
+ "reader", pthread_self(), (unsigned long)gettid());
+
+ rcu_register_thread();
+
+ while (!test_go)
+ {
+ }
+
+ for (;;) {
+ rcu_read_lock();
+ local_ptr = rcu_dereference(test_rcu_pointer);
+ debug_yield_read();
+ if (local_ptr)
+ assert(local_ptr->a == 8);
+ rcu_read_unlock();
+ nr_reads++;
+ if (!test_duration_read())
+ break;
+ }
+
+ rcu_unregister_thread();
+
+ *count = nr_reads;
+ printf("thread_end %s, thread id : %lx, tid %lu\n",
+ "reader", pthread_self(), (unsigned long)gettid());
+ return ((void*)1);
+
+}
+
+void *thr_writer(void *_count)
+{
+ unsigned long long *count = _count;
+ struct test_array *new, *old;
+
+ printf("thread_begin %s, thread id : %lx, tid %lu\n",
+ "writer", pthread_self(), (unsigned long)gettid());
+
+ while (!test_go)
+ {
+ }
+
+ for (;;) {
+ new = test_array_alloc();
+ rcu_copy_mutex_lock();
+ old = test_rcu_pointer;
+ if (old)
+ assert(old->a == 8);
+ new->a = 8;
+ old = rcu_publish_content(&test_rcu_pointer, new);
+ rcu_copy_mutex_unlock();
+ /* can be done after unlock */
+ if (old)
+ old->a = 0;
+ test_array_free(old);
+ nr_writes++;
+ if (!test_duration_write())
+ break;
+ if (wdelay)
+ usleep(wdelay);
+ }
+
+ printf("thread_end %s, thread id : %lx, tid %lu\n",
+ "writer", pthread_self(), (unsigned long)gettid());
+ *count = nr_writes;
+ return ((void*)2);
+}
+
+void show_usage(int argc, char **argv)
+{
+ printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]);
+#ifdef DEBUG_YIELD
+ printf(" [-r] [-w] (yield reader and/or writer)");
+#endif
+ printf(" [-d delay] (writer period)");
+ printf("\n");
+}
+
+int main(int argc, char **argv)
+{
+ int err;
+ pthread_t *tid_reader, *tid_writer;
+ void *tret;
+ unsigned long long *count_reader, *count_writer;
+ unsigned long long tot_reads = 0, tot_writes = 0;
+ int i;
+
+ if (argc < 4) {
+ show_usage(argc, argv);
+ return -1;
+ }
+
+ err = sscanf(argv[1], "%u", &nr_readers);
+ if (err != 1) {
+ show_usage(argc, argv);
+ return -1;
+ }
+
+ err = sscanf(argv[2], "%u", &nr_writers);
+ if (err != 1) {
+ show_usage(argc, argv);
+ return -1;
+ }
+
+ err = sscanf(argv[3], "%lu", &duration);
+ if (err != 1) {
+ show_usage(argc, argv);
+ return -1;
+ }
+
+ for (i = 4; i < argc; i++) {
+ if (argv[i][0] != '-')
+ continue;
+ switch (argv[i][1]) {
+#ifdef DEBUG_YIELD
+ case 'r':
+ yield_active |= YIELD_READ;
+ break;
+ case 'w':
+ yield_active |= YIELD_WRITE;
+ break;
+#endif
+ case 'd':
+ if (argc < i + 1) {
+ show_usage(argc, argv);
+ return -1;
+ }
+ wdelay = atoi(argv[++i]);
+ break;
+ }
+ }
+
+ printf("running test for %lu seconds, %u readers, %u writers.\n",
+ duration, nr_readers, nr_writers);
+ printf("Writer delay : %u us.\n", wdelay);
+ start_time = time(NULL);
+ printf("thread %-6s, thread id : %lx, tid %lu\n",
+ "main", pthread_self(), (unsigned long)gettid());
+
+ test_array = malloc(sizeof(*test_array) * ARRAY_SIZE);
+ tid_reader = malloc(sizeof(*tid_reader) * nr_readers);
+ tid_writer = malloc(sizeof(*tid_writer) * nr_writers);
+ count_reader = malloc(sizeof(*count_reader) * nr_readers);
+ count_writer = malloc(sizeof(*count_writer) * nr_writers);
+
+ for (i = 0; i < nr_readers; i++) {
+ err = pthread_create(&tid_reader[i], NULL, thr_reader,
+ &count_reader[i]);
+ if (err != 0)
+ exit(1);
+ }
+ for (i = 0; i < nr_writers; i++) {
+ err = pthread_create(&tid_writer[i], NULL, thr_writer,
+ &count_writer[i]);
+ if (err != 0)
+ exit(1);
+ }