On Fri, Nov 01, 2024 at 02:45:00PM +0800, David Gow wrote: > From: José Expósito <jose.exposito89@xxxxxxxxx> > > 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@xxxxxxxxx> > Co-developed-by: Matt Gilbride <mattgilbride@xxxxxxxxxx> > Signed-off-by: Matt Gilbride <mattgilbride@xxxxxxxxxx> > Co-developed-by: David Gow <davidgow@xxxxxxxxxx> > Signed-off-by: David Gow <davidgow@xxxxxxxxxx> > --- > > Changes since v3: > https://lore.kernel.org/linux-kselftest/20241030045719.3085147-4-davidgow@xxxxxxxxxx/ > - The kunit_unsafe_test_suite!() macro now panic!s if the suite name is > too long, triggering a compile error. (Thanks, Alice!) > > Changes since v2: > https://lore.kernel.org/linux-kselftest/20241029092422.2884505-2-davidgow@xxxxxxxxxx/ > - The kunit_unsafe_test_suite!() macro will truncate the name of the > suite if it is too long. (Thanks Alice!) > - We no longer needlessly use UnsafeCell<> in > kunit_unsafe_test_suite!(). (Thanks Alice!) > > Changes since v1: > https://lore.kernel.org/lkml/20230720-rustbind-v1-1-c80db349e3b5@xxxxxxxxxx/ > - 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 | 112 +++++++++++++++++++++++++++++++++++++++++++ > rust/kernel/lib.rs | 1 + > 2 files changed, 113 insertions(+) > > diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs > index 824da0e9738a..85bc1faff0d5 100644 > --- a/rust/kernel/kunit.rs > +++ b/rust/kernel/kunit.rs > @@ -161,3 +161,115 @@ 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: &'static kernel::str::CStr, run_case: unsafe extern "C" fn(*mut kernel::bindings::kunit)) -> kernel::bindings::kunit_case { > + kernel::bindings::kunit_case { > + run_case: Some(run_case), > + name: name.as_char_ptr(), > + attr: kernel::bindings::kunit_attributes { > + speed: kernel::bindings::kunit_speed_KUNIT_SPEED_NORMAL, > + }, > + generate_params: None, > + status: kernel::bindings::kunit_status_KUNIT_SUCCESS, > + module_name: core::ptr::null_mut(), > + log: core::ptr::null_mut(), > + } > +} > + > +/// Represents the NULL test case delimiter. > +/// > +/// The `kunit_unsafe_test_suite!` macro expects a NULL-terminated list of test cases. This > +/// function retuns such a delimiter. > +const fn kunit_case_null() -> kernel::bindings::kunit_case { > + kernel::bindings::kunit_case { > + run_case: None, > + name: core::ptr::null_mut(), > + generate_params: None, > + attr: kernel::bindings::kunit_attributes { > + speed: kernel::bindings::kunit_speed_KUNIT_SPEED_NORMAL, > + }, > + status: kernel::bindings::kunit_status_KUNIT_SUCCESS, > + module_name: core::ptr::null_mut(), > + log: core::ptr::null_mut(), > + } > +} > + > + > +/// 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]; > + > + if name_u8.len() > 255 { > + panic!(concat!("The test suite name `", core::stringify!($name), "` exceeds the maximum length of 255 bytes.")); > + } > + > + let mut i = 0; > + while i < name_u8.len() { > + ret[i] = name_u8[i] as i8; > + i += 1; > + } > + > + ret > + }; > + > + static mut KUNIT_TEST_SUITE: $crate::bindings::kunit_suite = > + $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 { core::ptr::addr_of_mut!(KUNIT_TEST_SUITE) }; FYI, `addr_of` and `addr_of_mut` is safe now on statics since 1.82: https://blog.rust-lang.org/2024/10/17/Rust-1.82.0.html#safely-addressing-unsafe-statics We need a `#[allow(unused_unsafe)]` here to avoid the unused unsafe warning. Regards, Boqun > + }; > + }; > +} > 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)] > > // Ensure conditional compilation based on the kernel configuration works; > // otherwise we may silently break things like initcall handling. > -- > 2.47.0.199.ga7371fff76-goog > >
