[PATCH v3 04/48] test_maple_tree: Test modifications while iterating

Liam Howlett
2023-01-17T02:34:42Z

Add a testcase to ensure the iterator detects bad states on modifications
and does what the user expects

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
lib/test_maple_tree.c | 72 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 72 insertions(+)

diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c
index ec847bf4dcb4..3d19b1f78d71 100644
--- a/lib/test_maple_tree.c
+++ b/lib/test_maple_tree.c
@@ -1709,6 +1709,74 @@ static noinline void check_forking(struct maple_tree *mt)
mtree_destroy(&newmt);
}

+static noinline void check_iteration(struct maple_tree *mt)
+{
+ int i, nr_entries = 125;
+ void *val;
+ MA_STATE(mas, mt, 0, 0);
+
+ for (i = 0; i <= nr_entries; i++)
+ mtree_store_range(mt, i * 10, i * 10 + 9,
+ xa_mk_value(i), GFP_KERNEL);
+
+ mt_set_non_kernel(99999);
+
+ i = 0;
+ mas_lock(&mas);
+ mas_for_each(&mas, val, 925) {
+ MT_BUG_ON(mt, mas.index != i * 10);
+ MT_BUG_ON(mt, mas.last != i * 10 + 9);
+ /* Overwrite end of entry 92 */
+ if (i == 92) {
+ mas.index = 925;
+ mas.last = 929;
+ mas_store(&mas, val);
+ }
+ i++;
+ }
+ /* Ensure mas_find() gets the next value */
+ val = mas_find(&mas, ULONG_MAX);
+ MT_BUG_ON(mt, val != xa_mk_value(i));
+
+ mas_set(&mas, 0);
+ i = 0;
+ mas_for_each(&mas, val, 785) {
+ MT_BUG_ON(mt, mas.index != i * 10);
+ MT_BUG_ON(mt, mas.last != i * 10 + 9);
+ /* Overwrite start of entry 78 */
+ if (i == 78) {
+ mas.index = 780;
+ mas.last = 785;
+ mas_store(&mas, val);
+ } else {
+ i++;
+ }
+ }
+ val = mas_find(&mas, ULONG_MAX);
+ MT_BUG_ON(mt, val != xa_mk_value(i));
+
+ mas_set(&mas, 0);
+ i = 0;
+ mas_for_each(&mas, val, 765) {
+ MT_BUG_ON(mt, mas.index != i * 10);
+ MT_BUG_ON(mt, mas.last != i * 10 + 9);
+ /* Overwrite end of entry 76 and advance to the end */
+ if (i == 76) {
+ mas.index = 760;
+ mas.last = 765;
+ mas_store(&mas, val);
+ mas_next(&mas, ULONG_MAX);
+ }
+ i++;
+ }
+ /* Make sure the next find returns the one after 765, 766-769 */
+ val = mas_find(&mas, ULONG_MAX);
+ MT_BUG_ON(mt, val != xa_mk_value(76));
+ mas_unlock(&mas);
+ mas_destroy(&mas);
+ mt_set_non_kernel(0);
+}
+
static noinline void check_mas_store_gfp(struct maple_tree *mt)
{

@@ -2659,6 +2727,10 @@ static int maple_tree_seed(void)
goto skip;
#endif

+ mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
+ check_iteration(&tree);
+ mtree_destroy(&tree);
+
mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
check_forking(&tree);
mtree_destroy(&tree);
--
2.35.1