[PATCH v2 09/19] rust: kunit: replace `kernel::c_str!` with C-Strings

Tamir Duberstein
2025-08-13T15:59:53Z

rust/kernel/kunit.rs        | 11 ++++-------
 rust/macros/kunit.rs        | 10 +++++-----
 scripts/rustdoc_test_gen.rs |  4 ++--
 3 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 3a43886cc14e..6223a5ac801c 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -9,9 +9,6 @@
 use crate::fmt;
 use crate::prelude::*;

-#[cfg(CONFIG_PRINTK)]
-use crate::c_str;
-
 /// Prints a KUnit error-level message.
 ///
 /// Public but hidden since it should only be used from KUnit generated code.
@@ -22,7 +19,7 @@ pub fn err(args: fmt::Arguments<'_>) {
     #[cfg(CONFIG_PRINTK)]
     unsafe {
         bindings::_printk(
-            c_str!("\x013%pA").as_char_ptr(),
+            c"\x013%pA".as_char_ptr(),
             core::ptr::from_ref(&args).cast::<c_void>(),
         );
     }
@@ -38,7 +35,7 @@ pub fn info(args: fmt::Arguments<'_>) {
     #[cfg(CONFIG_PRINTK)]
     unsafe {
         bindings::_printk(
-            c_str!("\x016%pA").as_char_ptr(),
+            c"\x016%pA".as_char_ptr(),
             core::ptr::from_ref(&args).cast::<c_void>(),
         );
     }
@@ -60,7 +57,7 @@ macro_rules! kunit_assert {
                 break 'out;
             }

-            static FILE: &'static $crate::str::CStr =
$crate::c_str!($file);
+            static FILE: &'static $crate::str::CStr = $file;
             static LINE: i32 = ::core::line!() as i32 - $diff;
             static CONDITION: &'static $crate::str::CStr =
$crate::c_str!(stringify!($condition));

@@ -249,7 +246,7 @@ pub const fn kunit_case_null() ->
kernel::bindings::kunit_case {
 /// }
 ///
 /// static mut KUNIT_TEST_CASES: [kernel::bindings::kunit_case; 2] = [
-///     kernel::kunit::kunit_case(kernel::c_str!("name"), test_fn),
+///     kernel::kunit::kunit_case(c"name", test_fn),
 ///     kernel::kunit::kunit_case_null(),
 /// ];
 /// kernel::kunit_unsafe_test_suite!(suite_name, KUNIT_TEST_CASES);
diff --git a/rust/macros/kunit.rs b/rust/macros/kunit.rs
index 81d18149a0cc..c64df1a01b9d 100644
--- a/rust/macros/kunit.rs
+++ b/rust/macros/kunit.rs
@@ -89,8 +89,8 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream)
-> TokenStream {
     // unsafe extern "C" fn kunit_rust_wrapper_bar(_test: *mut
::kernel::bindings::kunit) { bar(); }
     //
     // static mut TEST_CASES: [::kernel::bindings::kunit_case; 3] = [
-    //     ::kernel::kunit::kunit_case(::kernel::c_str!("foo"),
kunit_rust_wrapper_foo),
-    //     ::kernel::kunit::kunit_case(::kernel::c_str!("bar"),
kunit_rust_wrapper_bar),
+    //     ::kernel::kunit::kunit_case(c"foo",
kunit_rust_wrapper_foo),
+    //     ::kernel::kunit::kunit_case(c"bar",
kunit_rust_wrapper_bar),
     //     ::kernel::kunit::kunit_case_null(),
     // ];
     //
@@ -109,7 +109,7 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts:
TokenStream) -> TokenStream {
         writeln!(kunit_macros, "{kunit_wrapper}").unwrap();
         writeln!(
             test_cases,
-            "
::kernel::kunit::kunit_case(::kernel::c_str!(\"{test}\"),
{kunit_wrapper_fn_name}),"
+            "    ::kernel::kunit::kunit_case(c\"{test}\",
{kunit_wrapper_fn_name}),"
         )
         .unwrap();
         writeln!(
@@ -119,7 +119,7 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts:
TokenStream) -> TokenStream {
 #[allow(unused)]
 macro_rules! assert {{
     ($cond:expr $(,)?) => {{{{
-        kernel::kunit_assert!("{test}", "{path}", 0,
$cond);
+        kernel::kunit_assert!("{test}", c"{path}", 0,
$cond);
     }}}}
 }}

@@ -127,7 +127,7 @@ macro_rules! assert {{
 #[allow(unused)]
 macro_rules! assert_eq {{
     ($left:expr, $right:expr $(,)?) => {{{{
-        kernel::kunit_assert_eq!("{test}", "{path}", 0,
$left, $right);
+        kernel::kunit_assert_eq!("{test}", c"{path}", 0,
$left, $right);
     }}}}
 }}
         "#
diff --git a/scripts/rustdoc_test_gen.rs b/scripts/rustdoc_test_gen.rs
index c8f9dc2ab976..b0b70a3d0f54 100644
--- a/scripts/rustdoc_test_gen.rs
+++ b/scripts/rustdoc_test_gen.rs
@@ -174,7 +174,7 @@ pub extern "C" fn {kunit_name}(__kunit_test: *mut
::kernel::bindings::kunit) {{
     macro_rules! assert {{
         ($cond:expr $(,)?) => {{{{
             ::kernel::kunit_assert!(
-                "{kunit_name}", "{real_path}",
__DOCTEST_ANCHOR - {line}, $cond
+                "{kunit_name}", c"{real_path}",
__DOCTEST_ANCHOR - {line}, $cond
             );
         }}}}
     }}
@@ -184,7 +184,7 @@ macro_rules! assert {{
     macro_rules! assert_eq {{
         ($left:expr, $right:expr $(,)?) => {{{{
             ::kernel::kunit_assert_eq!(
-                "{kunit_name}", "{real_path}",
__DOCTEST_ANCHOR - {line}, $left, $right
+                "{kunit_name}", c"{real_path}",
__DOCTEST_ANCHOR - {line}, $left, $right
             );
         }}}}
     }}

--
2.50.1