Mailing List Archive

Add KUnit tests to the klist linked-list structure.
These perform testing for different variations of node add
and node delete in the klist data structure (<linux/klist.h>).

Limitation: Since we use a static global variable, and if
multiple instances of this test are run concurrently, the test may fail.

Signed-off-by: Sadiya Kazi <sadiyakazi@google.com>
---
lib/list-test.c | 298 +++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 297 insertions(+), 1 deletion(-)

diff --git a/lib/list-test.c b/lib/list-test.c
index d374cf5d1a57..af651cacb8f4 100644
--- a/lib/list-test.c
+++ b/lib/list-test.c
@@ -8,6 +8,7 @@
#include <kunit/test.h>

#include <linux/list.h>
+#include <linux/klist.h>

struct list_test_struct {
int data;
@@ -1199,6 +1200,301 @@ static struct kunit_suite hlist_test_module = {
.test_cases = hlist_test_cases,
};

-kunit_test_suites(&list_test_module, &hlist_test_module);
+
+struct klist_test_struct {
+ int data;
+ struct klist klist;
+ struct klist_node klist_node;
+};
+
+/* counts the number of nodes*/
+static int node_count;
+static struct klist_node *last_node_count;
+
+static void check_node(struct klist_node *node_ptr)
+{
+ node_count++;
+ last_node_count = node_ptr;
+}
+
+static void check_delete_node(struct klist_node *node_ptr)
+{
+ node_count--;
+ last_node_count = node_ptr;
+}
+
+static void klist_test_add_tail(struct kunit *test)
+{
+ struct klist_node a, b;
+ struct klist mylist;
+ struct klist_iter i;
+
+ node_count = 0;
+ klist_init(&mylist, &check_node, NULL);
+
+ klist_add_tail(&a, &mylist);
+ KUNIT_EXPECT_EQ(test, node_count, 1);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &a);
+
+ klist_add_tail(&b, &mylist);
+ KUNIT_EXPECT_EQ(test, node_count, 2);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &b);
+
+ /* should be [list] -> a -> b */
+ klist_iter_init(&mylist, &i);
+
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &a);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &b);
+ KUNIT_EXPECT_NULL(test, klist_next(&i));
+
+ klist_iter_exit(&i);
+
+}
+
+static void klist_test_add_head(struct kunit *test)
+{
+ struct klist_node a, b;
+ struct klist mylist;
+ struct klist_iter i;
+
+ node_count = 0;
+ klist_init(&mylist, &check_node, NULL);
+
+ klist_add_head(&a, &mylist);
+ KUNIT_EXPECT_EQ(test, node_count, 1);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &a);
+
+ klist_add_head(&b, &mylist);
+ KUNIT_EXPECT_EQ(test, node_count, 2);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &b);
+
+ /* should be [list] -> b -> a */
+ klist_iter_init(&mylist, &i);
+
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &b);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &a);
+ KUNIT_EXPECT_NULL(test, klist_next(&i));
+
+ klist_iter_exit(&i);
+
+}
+
+static void klist_test_add_behind(struct kunit *test)
+{
+ struct klist_node a, b, c, d;
+ struct klist mylist;
+ struct klist_iter i;
+
+ node_count = 0;
+ klist_init(&mylist, &check_node, NULL);
+
+ klist_add_head(&a, &mylist);
+ klist_add_head(&b, &mylist);
+
+ klist_add_behind(&c, &a);
+ KUNIT_EXPECT_EQ(test, node_count, 3);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &c);
+
+ klist_add_behind(&d, &b);
+ KUNIT_EXPECT_EQ(test, node_count, 4);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &d);
+
+ klist_iter_init(&mylist, &i);
+
+ /* should be [list] -> b -> d -> a -> c*/
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &b);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &d);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &a);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &c);
+ KUNIT_EXPECT_NULL(test, klist_next(&i));
+
+ klist_iter_exit(&i);
+
+}
+
+static void klist_test_add_before(struct kunit *test)
+{
+ struct klist_node a, b, c, d;
+ struct klist mylist;
+ struct klist_iter i;
+
+ node_count = 0;
+ klist_init(&mylist, &check_node, NULL);
+
+ klist_add_head(&a, &mylist);
+ klist_add_head(&b, &mylist);
+ klist_add_before(&c, &a);
+ KUNIT_EXPECT_EQ(test, node_count, 3);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &c);
+
+ klist_add_before(&d, &b);
+ KUNIT_EXPECT_EQ(test, node_count, 4);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &d);
+
+ klist_iter_init(&mylist, &i);
+
+ /* should be [list] -> b -> d -> a -> c*/
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &d);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &b);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &c);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &a);
+ KUNIT_EXPECT_NULL(test, klist_next(&i));
+
+ klist_iter_exit(&i);
+
+}
+
+/* Verify that klist_del() delays the deletion of a node until there
+ * are no other references to it
+ */
+static void klist_test_del_refcount_greater_than_zero(struct kunit *test)
+{
+ struct klist_node a, b, c, d;
+ struct klist mylist;
+ struct klist_iter i;
+
+ node_count = 0;
+ klist_init(&mylist, &check_node, &check_delete_node);
+
+ /* Add nodes a,b,c,d to the list*/
+ klist_add_tail(&a, &mylist);
+ klist_add_tail(&b, &mylist);
+ klist_add_tail(&c, &mylist);
+ klist_add_tail(&d, &mylist);
+
+ klist_iter_init(&mylist, &i);
+
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &a);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &b);
+ /* Advance the iterator to point to node c*/
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &c);
+
+ /* Try to delete node c while there is a reference to it*/
+ klist_del(&c);
+
+ /*
+ * Verify that node c is still attached to the list even after being
+ * deleted. Since the iterator still points to c, the reference count is not
+ * decreased to 0
+ */
+ KUNIT_EXPECT_TRUE(test, klist_node_attached(&c));
+
+ /* Check that node c has not been removed yet*/
+ KUNIT_EXPECT_EQ(test, node_count, 4);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &d);
+
+ klist_iter_exit(&i);
+
+ /* Since the iterator is no longer pointing to node c, node c is removed
+ * from the list
+ */
+ KUNIT_EXPECT_EQ(test, node_count, 3);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &c);
+
+}
+
+/* Verify that klist_del() deletes a node immediately when there are no
+ * other references to it.
+ */
+static void klist_test_del_refcount_zero(struct kunit *test)
+{
+ struct klist_node a, b, c, d;
+ struct klist mylist;
+ struct klist_iter i;
+
+ node_count = 0;
+ klist_init(&mylist, &check_node, &check_delete_node);
+
+ /* Add nodes a,b,c,d to the list*/
+ klist_add_tail(&a, &mylist);
+ klist_add_tail(&b, &mylist);
+ klist_add_tail(&c, &mylist);
+ klist_add_tail(&d, &mylist);
+ /* Delete node c*/
+ klist_del(&c);
+
+ /* Check that node c is deleted from the list*/
+ KUNIT_EXPECT_EQ(test, node_count, 3);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &c);
+
+ /* Should be [list] -> a -> b -> d*/
+ klist_iter_init(&mylist, &i);
+
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &a);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &b);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &d);
+ KUNIT_EXPECT_NULL(test, klist_next(&i));
+
+ klist_iter_exit(&i);
+
+}
+
+static void klist_test_remove(struct kunit *test)
+{
+ /* This test doesn't check correctness under concurrent access */
+ struct klist_node a, b, c, d;
+ struct klist mylist;
+ struct klist_iter i;
+
+ node_count = 0;
+ klist_init(&mylist, &check_node, &check_delete_node);
+
+ /* Add nodes a,b,c,d to the list*/
+ klist_add_tail(&a, &mylist);
+ klist_add_tail(&b, &mylist);
+ klist_add_tail(&c, &mylist);
+ klist_add_tail(&d, &mylist);
+ /* Delete node c*/
+ klist_remove(&c);
+
+ /* Check the nodes in the list*/
+ KUNIT_EXPECT_EQ(test, node_count, 3);
+ KUNIT_EXPECT_PTR_EQ(test, last_node_count, &c);
+
+ /* should be [list] -> a -> b -> d*/
+ klist_iter_init(&mylist, &i);
+
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &a);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &b);
+ KUNIT_EXPECT_PTR_EQ(test, klist_next(&i), &d);
+ KUNIT_EXPECT_NULL(test, klist_next(&i));
+
+ klist_iter_exit(&i);
+
+}
+
+static void klist_test_node_attached(struct kunit *test)
+{
+ struct klist_node a = {};
+ struct klist mylist;
+
+ klist_init(&mylist, NULL, NULL);
+
+ KUNIT_EXPECT_FALSE(test, klist_node_attached(&a));
+ klist_add_head(&a, &mylist);
+ KUNIT_EXPECT_TRUE(test, klist_node_attached(&a));
+ klist_del(&a);
+ KUNIT_EXPECT_FALSE(test, klist_node_attached(&a));
+
+}
+
+static struct kunit_case klist_test_cases[] = {
+ KUNIT_CASE(klist_test_add_tail),
+ KUNIT_CASE(klist_test_add_head),
+ KUNIT_CASE(klist_test_add_behind),
+ KUNIT_CASE(klist_test_add_before),
+ KUNIT_CASE(klist_test_del_refcount_greater_than_zero),
+ KUNIT_CASE(klist_test_del_refcount_zero),
+ KUNIT_CASE(klist_test_remove),
+ KUNIT_CASE(klist_test_node_attached),
+ {},
+};
+
+static struct kunit_suite klist_test_module = {
+ .name = "klist",
+ .test_cases = klist_test_cases,
+};
+
+kunit_test_suites(&list_test_module, &hlist_test_module, &klist_test_module);

MODULE_LICENSE("GPL v2");
--
2.40.0.348.gf938b09366-goog