On Tue, Oct 29, 2024 at 10:24 AM David Gow davidgow@google.com wrote:
From: José Expósito jose.exposito89@gmail.com
Add a couple of Rust const functions and macros to allow to develop KUnit tests without relying on generated C code:
- The `kunit_unsafe_test_suite!` Rust macro is similar to the `kunit_test_suite` C macro. It requires a NULL-terminated array of test cases (see below).
- The `kunit_case` Rust function is similar to the `KUNIT_CASE` C macro. It generates as case from the name and function.
- The `kunit_case_null` Rust function generates a NULL test case, which is to be used as delimiter in `kunit_test_suite!`.
While these functions and macros can be used on their own, a future patch will introduce another macro to create KUnit tests using a user-space like syntax.
Signed-off-by: José Expósito jose.exposito89@gmail.com Co-developed-by: Matt Gilbride mattgilbride@google.com Signed-off-by: Matt Gilbride mattgilbride@google.com Co-developed-by: David Gow davidgow@google.com Signed-off-by: David Gow davidgow@google.com
Changes since v1: https://lore.kernel.org/lkml/20230720-rustbind-v1-1-c80db349e3b5@google.com/
- Rebase on top of rust-next
- As a result, KUnit attributes are new set. These are hardcoded to the defaults of "normal" speed and no module name.
- Split the kunit_case!() macro into two const functions, kunit_case() and kunit_case_null() (for the NULL terminator).
rust/kernel/kunit.rs | 108 +++++++++++++++++++++++++++++++++++++++++++ rust/kernel/lib.rs | 1 + 2 files changed, 109 insertions(+)
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs index 824da0e9738a..fc2d259db458 100644 --- a/rust/kernel/kunit.rs +++ b/rust/kernel/kunit.rs @@ -161,3 +161,111 @@ macro_rules! kunit_assert_eq { $crate::kunit_assert!($name, $file, $diff, $left == $right); }}; }
+/// Represents an individual test case. +/// +/// The test case should have the signature +/// `unsafe extern "C" fn test_case(test: *mut crate::bindings::kunit)`. +/// +/// The `kunit_unsafe_test_suite!` macro expects a NULL-terminated list of test cases. +/// Use `kunit_case_null` to generate such a delimeter. +const fn kunit_case(name: &kernel::str::CStr, run_case: unsafe extern "C" fn(*mut kernel::bindings::kunit)) -> kernel::bindings::kunit_case {
This should probably say `name: &'static CStr` to require that the name lives forever.
+/// Registers a KUnit test suite. +/// +/// # Safety +/// +/// `test_cases` must be a NULL terminated array of test cases. +/// +/// # Examples +/// +/// ```ignore +/// unsafe extern "C" fn test_fn(_test: *mut crate::bindings::kunit) { +/// let actual = 1 + 1; +/// let expected = 2; +/// assert_eq!(actual, expected); +/// } +/// +/// static mut KUNIT_TEST_CASE: crate::bindings::kunit_case = crate::kunit_case(name, test_fn); +/// static mut KUNIT_NULL_CASE: crate::bindings::kunit_case = crate::kunit_case_null(); +/// static mut KUNIT_TEST_CASES: &mut[crate::bindings::kunit_case] = unsafe { +/// &mut[KUNIT_TEST_CASE, KUNIT_NULL_CASE] +/// }; +/// crate::kunit_unsafe_test_suite!(suite_name, KUNIT_TEST_CASES); +/// ``` +#[macro_export] +macro_rules! kunit_unsafe_test_suite {
- ($name:ident, $test_cases:ident) => {
const _: () = {static KUNIT_TEST_SUITE_NAME: [i8; 256] = {let name_u8 = core::stringify!($name).as_bytes();let mut ret = [0; 256];let mut i = 0;while i < name_u8.len() {ret[i] = name_u8[i] as i8;i += 1;}
I assume the name must be zero-terminated? If so, you probably need to enforce that somehow, e.g. by failing if `name_u8` is longer than 255 bytes.
static mut KUNIT_TEST_SUITE: core::cell::UnsafeCell<$crate::bindings::kunit_suite> =
You don't actually need UnsafeCell here since it's already `static mut`.
core::cell::UnsafeCell::new($crate::bindings::kunit_suite {name: KUNIT_TEST_SUITE_NAME,// SAFETY: User is expected to pass a correct `test_cases`, hence this macro// named 'unsafe'.test_cases: unsafe { $test_cases.as_mut_ptr() },suite_init: None,suite_exit: None,init: None,exit: None,attr: $crate::bindings::kunit_attributes {speed: $crate::bindings::kunit_speed_KUNIT_SPEED_NORMAL,},status_comment: [0; 256usize],debugfs: core::ptr::null_mut(),log: core::ptr::null_mut(),suite_init_err: 0,is_init: false,});#[used]#[link_section = ".kunit_test_suites"]static mut KUNIT_TEST_SUITE_ENTRY: *const $crate::bindings::kunit_suite =// SAFETY: `KUNIT_TEST_SUITE` is static.unsafe { KUNIT_TEST_SUITE.get() };
If you change `KUNIT_TEST_SUITE` to not be an UnsafeCell, then you'll want to do `core::ptr::addr_of_mut!(KUNIT_TEST_SUITE` instead.
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs index b62451f64f6e..d662aa37070f 100644 --- a/rust/kernel/lib.rs +++ b/rust/kernel/lib.rs @@ -18,6 +18,7 @@ #![feature(inline_const)] #![feature(lint_reasons)] #![feature(unsize)] +#![feature(const_mut_refs)]
Is this still needed with the above changes?
Alice