2 files changed, 14 insertions, 6 deletions

diff --git a/tools/testing/radix-tree/iteration_check.c b/tools/testing/radix-tree/iteration_check.c
index 9adb8e7415a6..11d570c3fc83 100644
--- a/tools/testing/radix-tree/iteration_check.c
+++ b/tools/testing/radix-tree/iteration_check.c
@@ -20,6 +20,7 @@
 #define TAG 0
 static pthread_mutex_t tree_lock = PTHREAD_MUTEX_INITIALIZER;
 static pthread_t threads[NUM_THREADS];
+static unsigned int seeds[3];
 RADIX_TREE(tree, GFP_KERNEL);
 bool test_complete;
 
@@ -71,7 +72,7 @@ static void *tagged_iteration_fn(void *arg)
 				continue;
 			}
 
-			if (rand() % 50 == 0)
+			if (rand_r(&seeds[0]) % 50 == 0)
 				slot = radix_tree_iter_next(&iter);
 		}
 		rcu_read_unlock();
@@ -111,7 +112,7 @@ static void *untagged_iteration_fn(void *arg)
 				continue;
 			}
 
-			if (rand() % 50 == 0)
+			if (rand_r(&seeds[1]) % 50 == 0)
 				slot = radix_tree_iter_next(&iter);
 		}
 		rcu_read_unlock();
@@ -129,7 +130,7 @@ static void *remove_entries_fn(void *arg)
 	while (!test_complete) {
 		int pgoff;
 
-		pgoff = rand() % 100;
+		pgoff = rand_r(&seeds[2]) % 100;
 
 		pthread_mutex_lock(&tree_lock);
 		item_delete(&tree, pgoff);
@@ -146,9 +147,11 @@ void iteration_test(void)
 
 	printf("Running iteration tests for 10 seconds\n");
 
-	srand(time(0));
 	test_complete = false;
 
+	for (i = 0; i < 3; i++)
+		seeds[i] = rand();
+
 	if (pthread_create(&threads[0], NULL, tagged_iteration_fn, NULL)) {
 		perror("pthread_create");
 		exit(1);
diff --git a/tools/testing/radix-tree/main.c b/tools/testing/radix-tree/main.c
index 52ce1eab0fd3..2eb694994497 100644
--- a/tools/testing/radix-tree/main.c
+++ b/tools/testing/radix-tree/main.c
@@ -67,7 +67,6 @@ void big_gang_check(bool long_run)
 
 	for (i = 0; i < (long_run ? 1000 : 3); i++) {
 		__big_gang_check();
-		srand(time(0));
 		printf("%d ", i);
 		fflush(stdout);
 	}
@@ -329,12 +328,18 @@ int main(int argc, char **argv)
 {
 	bool long_run = false;
 	int opt;
+	unsigned int seed = time(NULL);
 
-	while ((opt = getopt(argc, argv, "l")) != -1) {
+	while ((opt = getopt(argc, argv, "ls:")) != -1) {
 		if (opt == 'l')
 			long_run = true;
+		else if (opt == 's')
+			seed = strtoul(optarg, NULL, 0);
 	}
 
+	printf("random seed %u\n", seed);
+	srand(seed);
+
 	rcu_register_thread();
 	radix_tree_init();