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++) {