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authorLinus Torvalds <torvalds@linux-foundation.org>2023-08-28 18:56:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2023-08-28 18:56:38 -0700
commit815c24a085dd8ab9bb7381e455afdb3f9c260e38 (patch)
tree46cf481382c497cbbb47de63ca0a75183fc25875 /rust
parent5a31cc7297072a7266a910ca5266b640d27803b4 (diff)
parent25e324bc9cf2ee956eec1db384c39c1a17b7c44a (diff)
Merge tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kunit updates from Shuah Khan: - add support for running Rust documentation tests as KUnit tests - make init, str, sync, types doctests compilable/testable - add support for attributes API which include speed, modules attributes, ability to filter and report attributes - add support for marking tests slow using attributes API - add attributes API documentation - fix a wild-memory-access bug in kunit_filter_suites() and a possible memory leak in kunit_filter_suites() - add support for counting number of test suites in a module, list action to kunit test modules, and test filtering on module tests * tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits) kunit: fix struct kunit_attr header kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT kunit: Allow kunit test modules to use test filtering kunit: Make 'list' action available to kunit test modules kunit: Report the count of test suites in a module kunit: fix uninitialized variables bug in attributes filtering kunit: fix possible memory leak in kunit_filter_suites() kunit: fix wild-memory-access bug in kunit_filter_suites() kunit: Add documentation of KUnit test attributes kunit: add tests for filtering attributes kunit: time: Mark test as slow using test attributes kunit: memcpy: Mark tests as slow using test attributes kunit: tool: Add command line interface to filter and report attributes kunit: Add ability to filter attributes kunit: Add module attribute kunit: Add speed attribute kunit: Add test attributes API structure MAINTAINERS: add Rust KUnit files to the KUnit entry rust: support running Rust documentation tests as KUnit ones rust: types: make doctests compilable/testable ...
Diffstat (limited to 'rust')
-rw-r--r--rust/.gitignore2
-rw-r--r--rust/Makefile29
-rw-r--r--rust/bindings/bindings_helper.h1
-rw-r--r--rust/helpers.c7
-rw-r--r--rust/kernel/init.rs26
-rw-r--r--rust/kernel/kunit.rs163
-rw-r--r--rust/kernel/lib.rs2
-rw-r--r--rust/kernel/str.rs4
-rw-r--r--rust/kernel/sync/arc.rs9
-rw-r--r--rust/kernel/sync/lock/mutex.rs1
-rw-r--r--rust/kernel/sync/lock/spinlock.rs1
-rw-r--r--rust/kernel/types.rs6
12 files changed, 236 insertions, 15 deletions
diff --git a/rust/.gitignore b/rust/.gitignore
index 21552992b401..d3829ffab80b 100644
--- a/rust/.gitignore
+++ b/rust/.gitignore
@@ -2,6 +2,8 @@
bindings_generated.rs
bindings_helpers_generated.rs
+doctests_kernel_generated.rs
+doctests_kernel_generated_kunit.c
uapi_generated.rs
exports_*_generated.h
doc/
diff --git a/rust/Makefile b/rust/Makefile
index 4124bfa01798..30b71af119a2 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -27,6 +27,12 @@ endif
obj-$(CONFIG_RUST) += exports.o
+always-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated.rs
+always-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated_kunit.c
+
+obj-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated.o
+obj-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated_kunit.o
+
# Avoids running `$(RUSTC)` for the sysroot when it may not be available.
ifdef CONFIG_RUST
@@ -39,9 +45,11 @@ ifeq ($(quiet),silent_)
cargo_quiet=-q
rust_test_quiet=-q
rustdoc_test_quiet=--test-args -q
+rustdoc_test_kernel_quiet=>/dev/null
else ifeq ($(quiet),quiet_)
rust_test_quiet=-q
rustdoc_test_quiet=--test-args -q
+rustdoc_test_kernel_quiet=>/dev/null
else
cargo_quiet=--verbose
endif
@@ -157,6 +165,27 @@ quiet_cmd_rustdoc_test = RUSTDOC T $<
-L$(objtree)/$(obj)/test --output $(objtree)/$(obj)/doc \
--crate-name $(subst rusttest-,,$@) $<
+quiet_cmd_rustdoc_test_kernel = RUSTDOC TK $<
+ cmd_rustdoc_test_kernel = \
+ rm -rf $(objtree)/$(obj)/test/doctests/kernel; \
+ mkdir -p $(objtree)/$(obj)/test/doctests/kernel; \
+ OBJTREE=$(abspath $(objtree)) \
+ $(RUSTDOC) --test $(rust_flags) \
+ @$(objtree)/include/generated/rustc_cfg \
+ -L$(objtree)/$(obj) --extern alloc --extern kernel \
+ --extern build_error --extern macros \
+ --extern bindings --extern uapi \
+ --no-run --crate-name kernel -Zunstable-options \
+ --test-builder $(objtree)/scripts/rustdoc_test_builder \
+ $< $(rustdoc_test_kernel_quiet); \
+ $(objtree)/scripts/rustdoc_test_gen
+
+%/doctests_kernel_generated.rs %/doctests_kernel_generated_kunit.c: \
+ $(src)/kernel/lib.rs $(obj)/kernel.o \
+ $(objtree)/scripts/rustdoc_test_builder \
+ $(objtree)/scripts/rustdoc_test_gen FORCE
+ $(call if_changed,rustdoc_test_kernel)
+
# We cannot use `-Zpanic-abort-tests` because some tests are dynamic,
# so for the moment we skip `-Cpanic=abort`.
quiet_cmd_rustc_test = RUSTC T $<
diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index 058954961bfc..c91a3c24f607 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -6,6 +6,7 @@
* Sorted alphabetically.
*/
+#include <kunit/test.h>
#include <linux/errname.h>
#include <linux/slab.h>
#include <linux/refcount.h>
diff --git a/rust/helpers.c b/rust/helpers.c
index bb594da56137..49a5e1a4f0ae 100644
--- a/rust/helpers.c
+++ b/rust/helpers.c
@@ -18,6 +18,7 @@
* accidentally exposed.
*/
+#include <kunit/test-bug.h>
#include <linux/bug.h>
#include <linux/build_bug.h>
#include <linux/err.h>
@@ -135,6 +136,12 @@ void rust_helper_put_task_struct(struct task_struct *t)
}
EXPORT_SYMBOL_GPL(rust_helper_put_task_struct);
+struct kunit *rust_helper_kunit_get_current_test(void)
+{
+ return kunit_get_current_test();
+}
+EXPORT_SYMBOL_GPL(rust_helper_kunit_get_current_test);
+
/*
* We use `bindgen`'s `--size_t-is-usize` option to bind the C `size_t` type
* as the Rust `usize` type, so we can use it in contexts where Rust
diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs
index b4332a4ec1f4..e05563aad2ed 100644
--- a/rust/kernel/init.rs
+++ b/rust/kernel/init.rs
@@ -120,14 +120,24 @@
//! `slot` gets called.
//!
//! ```rust
-//! use kernel::{prelude::*, init};
+//! # #![allow(unreachable_pub, clippy::disallowed_names)]
+//! use kernel::{prelude::*, init, types::Opaque};
//! use core::{ptr::addr_of_mut, marker::PhantomPinned, pin::Pin};
//! # mod bindings {
+//! # #![allow(non_camel_case_types)]
//! # pub struct foo;
//! # pub unsafe fn init_foo(_ptr: *mut foo) {}
//! # pub unsafe fn destroy_foo(_ptr: *mut foo) {}
//! # pub unsafe fn enable_foo(_ptr: *mut foo, _flags: u32) -> i32 { 0 }
//! # }
+//! # // `Error::from_errno` is `pub(crate)` in the `kernel` crate, thus provide a workaround.
+//! # trait FromErrno {
+//! # fn from_errno(errno: core::ffi::c_int) -> Error {
+//! # // Dummy error that can be constructed outside the `kernel` crate.
+//! # Error::from(core::fmt::Error)
+//! # }
+//! # }
+//! # impl FromErrno for Error {}
//! /// # Invariants
//! ///
//! /// `foo` is always initialized
@@ -158,7 +168,7 @@
//! if err != 0 {
//! // Enabling has failed, first clean up the foo and then return the error.
//! bindings::destroy_foo(Opaque::raw_get(foo));
-//! return Err(Error::from_kernel_errno(err));
+//! return Err(Error::from_errno(err));
//! }
//!
//! // All fields of `RawFoo` have been initialized, since `_p` is a ZST.
@@ -226,8 +236,7 @@ pub mod macros;
///
/// ```rust
/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)]
-/// # use kernel::{init, pin_init, stack_pin_init, init::*, sync::Mutex, new_mutex};
-/// # use macros::pin_data;
+/// # use kernel::{init, macros::pin_data, pin_init, stack_pin_init, init::*, sync::Mutex, new_mutex};
/// # use core::pin::Pin;
/// #[pin_data]
/// struct Foo {
@@ -277,7 +286,7 @@ macro_rules! stack_pin_init {
///
/// # Examples
///
-/// ```rust
+/// ```rust,ignore
/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)]
/// # use kernel::{init, pin_init, stack_try_pin_init, init::*, sync::Mutex, new_mutex};
/// # use macros::pin_data;
@@ -303,7 +312,7 @@ macro_rules! stack_pin_init {
/// pr_info!("a: {}", &*foo.a.lock());
/// ```
///
-/// ```rust
+/// ```rust,ignore
/// # #![allow(clippy::disallowed_names, clippy::new_ret_no_self)]
/// # use kernel::{init, pin_init, stack_try_pin_init, init::*, sync::Mutex, new_mutex};
/// # use macros::pin_data;
@@ -513,8 +522,7 @@ macro_rules! stack_try_pin_init {
/// For instance:
///
/// ```rust
-/// # use kernel::pin_init;
-/// # use macros::pin_data;
+/// # use kernel::{macros::pin_data, pin_init};
/// # use core::{ptr::addr_of_mut, marker::PhantomPinned};
/// #[pin_data]
/// struct Buf {
@@ -841,7 +849,7 @@ macro_rules! init {
/// # Examples
///
/// ```rust
-/// use kernel::{init::PinInit, error::Error, InPlaceInit};
+/// use kernel::{init::{PinInit, zeroed}, error::Error};
/// struct BigBuf {
/// big: Box<[u8; 1024 * 1024 * 1024]>,
/// small: [u8; 1024 * 1024],
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
new file mode 100644
index 000000000000..722655b2d62d
--- /dev/null
+++ b/rust/kernel/kunit.rs
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! KUnit-based macros for Rust unit tests.
+//!
+//! C header: [`include/kunit/test.h`](../../../../../include/kunit/test.h)
+//!
+//! Reference: <https://docs.kernel.org/dev-tools/kunit/index.html>
+
+use core::{ffi::c_void, fmt};
+
+/// Prints a KUnit error-level message.
+///
+/// Public but hidden since it should only be used from KUnit generated code.
+#[doc(hidden)]
+pub fn err(args: fmt::Arguments<'_>) {
+ // SAFETY: The format string is null-terminated and the `%pA` specifier matches the argument we
+ // are passing.
+ #[cfg(CONFIG_PRINTK)]
+ unsafe {
+ bindings::_printk(
+ b"\x013%pA\0".as_ptr() as _,
+ &args as *const _ as *const c_void,
+ );
+ }
+}
+
+/// Prints a KUnit info-level message.
+///
+/// Public but hidden since it should only be used from KUnit generated code.
+#[doc(hidden)]
+pub fn info(args: fmt::Arguments<'_>) {
+ // SAFETY: The format string is null-terminated and the `%pA` specifier matches the argument we
+ // are passing.
+ #[cfg(CONFIG_PRINTK)]
+ unsafe {
+ bindings::_printk(
+ b"\x016%pA\0".as_ptr() as _,
+ &args as *const _ as *const c_void,
+ );
+ }
+}
+
+/// Asserts that a boolean expression is `true` at runtime.
+///
+/// Public but hidden since it should only be used from generated tests.
+///
+/// Unlike the one in `core`, this one does not panic; instead, it is mapped to the KUnit
+/// facilities. See [`assert!`] for more details.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! kunit_assert {
+ ($name:literal, $file:literal, $diff:expr, $condition:expr $(,)?) => {
+ 'out: {
+ // Do nothing if the condition is `true`.
+ if $condition {
+ break 'out;
+ }
+
+ static FILE: &'static $crate::str::CStr = $crate::c_str!($file);
+ static LINE: i32 = core::line!() as i32 - $diff;
+ static CONDITION: &'static $crate::str::CStr = $crate::c_str!(stringify!($condition));
+
+ // SAFETY: FFI call without safety requirements.
+ let kunit_test = unsafe { $crate::bindings::kunit_get_current_test() };
+ if kunit_test.is_null() {
+ // The assertion failed but this task is not running a KUnit test, so we cannot call
+ // KUnit, but at least print an error to the kernel log. This may happen if this
+ // macro is called from an spawned thread in a test (see
+ // `scripts/rustdoc_test_gen.rs`) or if some non-test code calls this macro by
+ // mistake (it is hidden to prevent that).
+ //
+ // This mimics KUnit's failed assertion format.
+ $crate::kunit::err(format_args!(
+ " # {}: ASSERTION FAILED at {FILE}:{LINE}\n",
+ $name
+ ));
+ $crate::kunit::err(format_args!(
+ " Expected {CONDITION} to be true, but is false\n"
+ ));
+ $crate::kunit::err(format_args!(
+ " Failure not reported to KUnit since this is a non-KUnit task\n"
+ ));
+ break 'out;
+ }
+
+ #[repr(transparent)]
+ struct Location($crate::bindings::kunit_loc);
+
+ #[repr(transparent)]
+ struct UnaryAssert($crate::bindings::kunit_unary_assert);
+
+ // SAFETY: There is only a static instance and in that one the pointer field points to
+ // an immutable C string.
+ unsafe impl Sync for Location {}
+
+ // SAFETY: There is only a static instance and in that one the pointer field points to
+ // an immutable C string.
+ unsafe impl Sync for UnaryAssert {}
+
+ static LOCATION: Location = Location($crate::bindings::kunit_loc {
+ file: FILE.as_char_ptr(),
+ line: LINE,
+ });
+ static ASSERTION: UnaryAssert = UnaryAssert($crate::bindings::kunit_unary_assert {
+ assert: $crate::bindings::kunit_assert {},
+ condition: CONDITION.as_char_ptr(),
+ expected_true: true,
+ });
+
+ // SAFETY:
+ // - FFI call.
+ // - The `kunit_test` pointer is valid because we got it from
+ // `kunit_get_current_test()` and it was not null. This means we are in a KUnit
+ // test, and that the pointer can be passed to KUnit functions and assertions.
+ // - The string pointers (`file` and `condition` above) point to null-terminated
+ // strings since they are `CStr`s.
+ // - The function pointer (`format`) points to the proper function.
+ // - The pointers passed will remain valid since they point to `static`s.
+ // - The format string is allowed to be null.
+ // - There are, however, problems with this: first of all, this will end up stopping
+ // the thread, without running destructors. While that is problematic in itself,
+ // it is considered UB to have what is effectively a forced foreign unwind
+ // with `extern "C"` ABI. One could observe the stack that is now gone from
+ // another thread. We should avoid pinning stack variables to prevent library UB,
+ // too. For the moment, given that test failures are reported immediately before the
+ // next test runs, that test failures should be fixed and that KUnit is explicitly
+ // documented as not suitable for production environments, we feel it is reasonable.
+ unsafe {
+ $crate::bindings::__kunit_do_failed_assertion(
+ kunit_test,
+ core::ptr::addr_of!(LOCATION.0),
+ $crate::bindings::kunit_assert_type_KUNIT_ASSERTION,
+ core::ptr::addr_of!(ASSERTION.0.assert),
+ Some($crate::bindings::kunit_unary_assert_format),
+ core::ptr::null(),
+ );
+ }
+
+ // SAFETY: FFI call; the `test` pointer is valid because this hidden macro should only
+ // be called by the generated documentation tests which forward the test pointer given
+ // by KUnit.
+ unsafe {
+ $crate::bindings::__kunit_abort(kunit_test);
+ }
+ }
+ };
+}
+
+/// Asserts that two expressions are equal to each other (using [`PartialEq`]).
+///
+/// Public but hidden since it should only be used from generated tests.
+///
+/// Unlike the one in `core`, this one does not panic; instead, it is mapped to the KUnit
+/// facilities. See [`assert!`] for more details.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! kunit_assert_eq {
+ ($name:literal, $file:literal, $diff:expr, $left:expr, $right:expr $(,)?) => {{
+ // For the moment, we just forward to the expression assert because, for binary asserts,
+ // KUnit supports only a few types (e.g. integers).
+ $crate::kunit_assert!($name, $file, $diff, $left == $right);
+ }};
+}
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 85b261209977..3642cadc34b1 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -34,6 +34,8 @@ mod build_assert;
pub mod error;
pub mod init;
pub mod ioctl;
+#[cfg(CONFIG_KUNIT)]
+pub mod kunit;
pub mod prelude;
pub mod print;
mod static_assert;
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index c9dd3bf59e34..c41607b2e4fe 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -213,6 +213,7 @@ impl fmt::Display for CStr {
///
/// ```
/// # use kernel::c_str;
+ /// # use kernel::fmt;
/// # use kernel::str::CStr;
/// # use kernel::str::CString;
/// let penguin = c_str!("🐧");
@@ -241,6 +242,7 @@ impl fmt::Debug for CStr {
///
/// ```
/// # use kernel::c_str;
+ /// # use kernel::fmt;
/// # use kernel::str::CStr;
/// # use kernel::str::CString;
/// let penguin = c_str!("🐧");
@@ -529,7 +531,7 @@ impl fmt::Write for Formatter {
/// # Examples
///
/// ```
-/// use kernel::str::CString;
+/// use kernel::{str::CString, fmt};
///
/// let s = CString::try_from_fmt(fmt!("{}{}{}", "abc", 10, 20)).unwrap();
/// assert_eq!(s.as_bytes_with_nul(), "abc1020\0".as_bytes());
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index 172f563976a9..3d496391a9bd 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -73,6 +73,7 @@ mod std_vendor;
/// assert_eq!(cloned.b, 20);
///
/// // The refcount drops to zero when `cloned` goes out of scope, and the memory is freed.
+/// # Ok::<(), Error>(())
/// ```
///
/// Using `Arc<T>` as the type of `self`:
@@ -98,6 +99,7 @@ mod std_vendor;
/// let obj = Arc::try_new(Example { a: 10, b: 20 })?;
/// obj.use_reference();
/// obj.take_over();
+/// # Ok::<(), Error>(())
/// ```
///
/// Coercion from `Arc<Example>` to `Arc<dyn MyTrait>`:
@@ -121,6 +123,7 @@ mod std_vendor;
///
/// // `coerced` has type `Arc<dyn MyTrait>`.
/// let coerced: Arc<dyn MyTrait> = obj;
+/// # Ok::<(), Error>(())
/// ```
pub struct Arc<T: ?Sized> {
ptr: NonNull<ArcInner<T>>,
@@ -336,7 +339,7 @@ impl<T: ?Sized> From<Pin<UniqueArc<T>>> for Arc<T> {
/// # Example
///
/// ```
-/// use crate::sync::{Arc, ArcBorrow};
+/// use kernel::sync::{Arc, ArcBorrow};
///
/// struct Example;
///
@@ -349,12 +352,13 @@ impl<T: ?Sized> From<Pin<UniqueArc<T>>> for Arc<T> {
///
/// // Assert that both `obj` and `cloned` point to the same underlying object.
/// assert!(core::ptr::eq(&*obj, &*cloned));
+/// # Ok::<(), Error>(())
/// ```
///
/// Using `ArcBorrow<T>` as the type of `self`:
///
/// ```
-/// use crate::sync::{Arc, ArcBorrow};
+/// use kernel::sync::{Arc, ArcBorrow};
///
/// struct Example {
/// a: u32,
@@ -369,6 +373,7 @@ impl<T: ?Sized> From<Pin<UniqueArc<T>>> for Arc<T> {
///
/// let obj = Arc::try_new(Example { a: 10, b: 20 })?;
/// obj.as_arc_borrow().use_reference();
+/// # Ok::<(), Error>(())
/// ```
pub struct ArcBorrow<'a, T: ?Sized + 'a> {
inner: NonNull<ArcInner<T>>,
diff --git a/rust/kernel/sync/lock/mutex.rs b/rust/kernel/sync/lock/mutex.rs
index 923472f04af4..09276fedc091 100644
--- a/rust/kernel/sync/lock/mutex.rs
+++ b/rust/kernel/sync/lock/mutex.rs
@@ -63,6 +63,7 @@ macro_rules! new_mutex {
/// assert_eq!(e.c, 10);
/// assert_eq!(e.d.lock().a, 20);
/// assert_eq!(e.d.lock().b, 30);
+/// # Ok::<(), Error>(())
/// ```
///
/// The following example shows how to use interior mutability to modify the contents of a struct
diff --git a/rust/kernel/sync/lock/spinlock.rs b/rust/kernel/sync/lock/spinlock.rs
index 979b56464a4e..91eb2c9e9123 100644
--- a/rust/kernel/sync/lock/spinlock.rs
+++ b/rust/kernel/sync/lock/spinlock.rs
@@ -61,6 +61,7 @@ macro_rules! new_spinlock {
/// assert_eq!(e.c, 10);
/// assert_eq!(e.d.lock().a, 20);
/// assert_eq!(e.d.lock().b, 30);
+/// # Ok::<(), Error>(())
/// ```
///
/// The following example shows how to use interior mutability to modify the contents of a struct
diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs
index d479f8da8f38..e33b901ab0a4 100644
--- a/rust/kernel/types.rs
+++ b/rust/kernel/types.rs
@@ -91,7 +91,7 @@ impl ForeignOwnable for () {
/// In the example below, we have multiple exit paths and we want to log regardless of which one is
/// taken:
/// ```
-/// # use kernel::ScopeGuard;
+/// # use kernel::types::ScopeGuard;
/// fn example1(arg: bool) {
/// let _log = ScopeGuard::new(|| pr_info!("example1 completed\n"));
///
@@ -109,7 +109,7 @@ impl ForeignOwnable for () {
/// In the example below, we want to log the same message on all early exits but a different one on
/// the main exit path:
/// ```
-/// # use kernel::ScopeGuard;
+/// # use kernel::types::ScopeGuard;
/// fn example2(arg: bool) {
/// let log = ScopeGuard::new(|| pr_info!("example2 returned early\n"));
///
@@ -130,7 +130,7 @@ impl ForeignOwnable for () {
/// In the example below, we need a mutable object (the vector) to be accessible within the log
/// function, so we wrap it in the [`ScopeGuard`]:
/// ```
-/// # use kernel::ScopeGuard;
+/// # use kernel::types::ScopeGuard;
/// fn example3(arg: bool) -> Result {
/// let mut vec =
/// ScopeGuard::new_with_data(Vec::new(), |v| pr_info!("vec had {} elements\n", v.len()));