1 files changed, 82 insertions, 41 deletions

diff --git a/tools/testing/radix-tree/iteration_check.c b/tools/testing/radix-tree/iteration_check.c
index 9adb8e7415a6..7572b7ed930e 100644
--- a/tools/testing/radix-tree/iteration_check.c
+++ b/tools/testing/radix-tree/iteration_check.c
@@ -16,35 +16,50 @@
 #include <pthread.h>
 #include "test.h"
 
-#define NUM_THREADS 4
-#define TAG 0
+#define NUM_THREADS	5
+#define MAX_IDX		100
+#define TAG		0
+#define NEW_TAG		1
+
 static pthread_mutex_t tree_lock = PTHREAD_MUTEX_INITIALIZER;
 static pthread_t threads[NUM_THREADS];
-RADIX_TREE(tree, GFP_KERNEL);
-bool test_complete;
+static unsigned int seeds[3];
+static RADIX_TREE(tree, GFP_KERNEL);
+static bool test_complete;
+static int max_order;
 
 /* relentlessly fill the tree with tagged entries */
 static void *add_entries_fn(void *arg)
 {
-	int pgoff;
+	rcu_register_thread();
 
 	while (!test_complete) {
-		for (pgoff = 0; pgoff < 100; pgoff++) {
+		unsigned long pgoff;
+		int order;
+
+		for (pgoff = 0; pgoff < MAX_IDX; pgoff++) {
 			pthread_mutex_lock(&tree_lock);
-			if (item_insert(&tree, pgoff) == 0)
-				item_tag_set(&tree, pgoff, TAG);
+			for (order = max_order; order >= 0; order--) {
+				if (item_insert_order(&tree, pgoff, order)
+						== 0) {
+					item_tag_set(&tree, pgoff, TAG);
+					break;
+				}
+			}
 			pthread_mutex_unlock(&tree_lock);
 		}
 	}
 
+	rcu_unregister_thread();
+
 	return NULL;
 }
 
 /*
  * Iterate over the tagged entries, doing a radix_tree_iter_retry() as we find
  * things that have been removed and randomly resetting our iteration to the
- * next chunk with radix_tree_iter_next().  Both radix_tree_iter_retry() and
- * radix_tree_iter_next() cause radix_tree_next_slot() to be called with a
+ * next chunk with radix_tree_iter_resume().  Both radix_tree_iter_retry() and
+ * radix_tree_iter_resume() cause radix_tree_next_slot() to be called with a
  * NULL 'slot' variable.
  */
 static void *tagged_iteration_fn(void *arg)
@@ -52,17 +67,12 @@ static void *tagged_iteration_fn(void *arg)
 	struct radix_tree_iter iter;
 	void **slot;
 
+	rcu_register_thread();
+
 	while (!test_complete) {
 		rcu_read_lock();
 		radix_tree_for_each_tagged(slot, &tree, &iter, 0, TAG) {
-			void *entry;
-			int i;
-
-			/* busy wait to let removals happen */
-			for (i = 0; i < 1000000; i++)
-				;
-
-			entry = radix_tree_deref_slot(slot);
+			void *entry = radix_tree_deref_slot(slot);
 			if (unlikely(!entry))
 				continue;
 
@@ -71,20 +81,26 @@ static void *tagged_iteration_fn(void *arg)
 				continue;
 			}
 
-			if (rand() % 50 == 0)
-				slot = radix_tree_iter_next(&iter);
+			if (rand_r(&seeds[0]) % 50 == 0) {
+				slot = radix_tree_iter_resume(slot, &iter);
+				rcu_read_unlock();
+				rcu_barrier();
+				rcu_read_lock();
+			}
 		}
 		rcu_read_unlock();
 	}
 
+	rcu_unregister_thread();
+
 	return NULL;
 }
 
 /*
  * Iterate over the entries, doing a radix_tree_iter_retry() as we find things
  * that have been removed and randomly resetting our iteration to the next
- * chunk with radix_tree_iter_next().  Both radix_tree_iter_retry() and
- * radix_tree_iter_next() cause radix_tree_next_slot() to be called with a
+ * chunk with radix_tree_iter_resume().  Both radix_tree_iter_retry() and
+ * radix_tree_iter_resume() cause radix_tree_next_slot() to be called with a
  * NULL 'slot' variable.
  */
 static void *untagged_iteration_fn(void *arg)
@@ -92,17 +108,12 @@ static void *untagged_iteration_fn(void *arg)
 	struct radix_tree_iter iter;
 	void **slot;
 
+	rcu_register_thread();
+
 	while (!test_complete) {
 		rcu_read_lock();
 		radix_tree_for_each_slot(slot, &tree, &iter, 0) {
-			void *entry;
-			int i;
-
-			/* busy wait to let removals happen */
-			for (i = 0; i < 1000000; i++)
-				;
-
-			entry = radix_tree_deref_slot(slot);
+			void *entry = radix_tree_deref_slot(slot);
 			if (unlikely(!entry))
 				continue;
 
@@ -111,12 +122,18 @@ static void *untagged_iteration_fn(void *arg)
 				continue;
 			}
 
-			if (rand() % 50 == 0)
-				slot = radix_tree_iter_next(&iter);
+			if (rand_r(&seeds[1]) % 50 == 0) {
+				slot = radix_tree_iter_resume(slot, &iter);
+				rcu_read_unlock();
+				rcu_barrier();
+				rcu_read_lock();
+			}
 		}
 		rcu_read_unlock();
 	}
 
+	rcu_unregister_thread();
+
 	return NULL;
 }
 
@@ -126,47 +143,71 @@ static void *untagged_iteration_fn(void *arg)
  */
 static void *remove_entries_fn(void *arg)
 {
+	rcu_register_thread();
+
 	while (!test_complete) {
 		int pgoff;
 
-		pgoff = rand() % 100;
+		pgoff = rand_r(&seeds[2]) % MAX_IDX;
 
 		pthread_mutex_lock(&tree_lock);
 		item_delete(&tree, pgoff);
 		pthread_mutex_unlock(&tree_lock);
 	}
 
+	rcu_unregister_thread();
+
+	return NULL;
+}
+
+static void *tag_entries_fn(void *arg)
+{
+	rcu_register_thread();
+
+	while (!test_complete) {
+		tag_tagged_items(&tree, &tree_lock, 0, MAX_IDX, 10, TAG,
+					NEW_TAG);
+	}
+	rcu_unregister_thread();
 	return NULL;
 }
 
 /* This is a unit test for a bug found by the syzkaller tester */
-void iteration_test(void)
+void iteration_test(unsigned order, unsigned test_duration)
 {
 	int i;
 
-	printf("Running iteration tests for 10 seconds\n");
+	printf("Running %siteration tests for %d seconds\n",
+			order > 0 ? "multiorder " : "", test_duration);
 
-	srand(time(0));
+	max_order = order;
 	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");
+		perror("create tagged iteration thread");
 		exit(1);
 	}
 	if (pthread_create(&threads[1], NULL, untagged_iteration_fn, NULL)) {
-		perror("pthread_create");
+		perror("create untagged iteration thread");
 		exit(1);
 	}
 	if (pthread_create(&threads[2], NULL, add_entries_fn, NULL)) {
-		perror("pthread_create");
+		perror("create add entry thread");
 		exit(1);
 	}
 	if (pthread_create(&threads[3], NULL, remove_entries_fn, NULL)) {
-		perror("pthread_create");
+		perror("create remove entry thread");
+		exit(1);
+	}
+	if (pthread_create(&threads[4], NULL, tag_entries_fn, NULL)) {
+		perror("create tag entry thread");
 		exit(1);
 	}
 
-	sleep(10);
+	sleep(test_duration);
 	test_complete = true;
 
 	for (i = 0; i < NUM_THREADS; i++) {