list_is_head() was added recently[1], and didn't have a KUnit test. The implementation is trivial, so it's not a particularly exciting test, but it'd be nice to get back to full coverage of the list functions.
[1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/in...
Signed-off-by: David Gow davidgow@google.com Acked-by: Daniel Latypov dlatypov@google.com Acked-by: Brendan Higgins brendanhiggins@google.com Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com ---
Changes since v3: https://lore.kernel.org/lkml/20220209052813.854014-2-davidgow@google.com/ - Add Reviewed-by tags.
Changes since v2: https://lore.kernel.org/linux-kselftest/20220208040122.695258-2-davidgow@goo... - Use the _MSG variants of the assert macros, as suggested by Daniel Latypov.
Changes since v1: https://lore.kernel.org/linux-kselftest/20220205061539.273330-2-davidgow@goo... - Test both non-head elements of the same list and head elements of different lists.
--- lib/list-test.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)
diff --git a/lib/list-test.c b/lib/list-test.c index 302b7382bff4..3870ebfd84aa 100644 --- a/lib/list-test.c +++ b/lib/list-test.c @@ -254,6 +254,24 @@ static void list_test_list_bulk_move_tail(struct kunit *test) KUNIT_EXPECT_EQ(test, i, 2); }
+static void list_test_list_is_head(struct kunit *test) +{ + struct list_head a, b, c; + + /* Two lists: [a] -> b, [c] */ + INIT_LIST_HEAD(&a); + INIT_LIST_HEAD(&c); + list_add_tail(&b, &a); + + KUNIT_EXPECT_TRUE_MSG(test, list_is_head(&a, &a), + "Head element of same list"); + KUNIT_EXPECT_FALSE_MSG(test, list_is_head(&a, &b), + "Non-head element of same list"); + KUNIT_EXPECT_FALSE_MSG(test, list_is_head(&a, &c), + "Head element of different list"); +} + + static void list_test_list_is_first(struct kunit *test) { struct list_head a, b; @@ -731,6 +749,7 @@ static struct kunit_case list_test_cases[] = { KUNIT_CASE(list_test_list_move), KUNIT_CASE(list_test_list_move_tail), KUNIT_CASE(list_test_list_bulk_move_tail), + KUNIT_CASE(list_test_list_is_head), KUNIT_CASE(list_test_list_is_first), KUNIT_CASE(list_test_list_is_last), KUNIT_CASE(list_test_list_empty),