[PATCH] i2c: rust: mark I2cAdapter methods as inline
From: Nicolás Antinori
Date: Thu May 21 2026 - 15:10:41 EST
When building the kernel using llvm-19.1.7-rust-1.85.0-x86_64, the
following symbols are generated:
$ nm vmlinux | grep ' _R'.*I2cAdapter | rustfilt
ffffffff817ff380 T <kernel::i2c::I2cAdapter>::get
ffffffff817ff400 T <kernel::i2c::I2cAdapter as kernel::sync::aref::AlwaysRefCounted>::dec_ref
ffffffff817ff3e0 T <kernel::i2c::I2cAdapter as kernel::sync::aref::AlwaysRefCounted>::inc_ref
However, these Rust symbols are trivial wrappers around the
`i2c_get_adapter` and `i2c_put_adapter` functions. It doesn't make sense
to go through a trivial wrapper for these functions.
Link: https://github.com/Rust-for-Linux/linux/issues/1145
Suggested-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
Signed-off-by: Nicolás Antinori <nico.antinori.7@xxxxxxxxx>
---
rust/kernel/i2c.rs | 3 +++
1 file changed, 3 insertions(+)
diff --git a/rust/kernel/i2c.rs b/rust/kernel/i2c.rs
index 7b908f0c5a58..07f9fd53c4e5 100644
--- a/rust/kernel/i2c.rs
+++ b/rust/kernel/i2c.rs
@@ -397,6 +397,7 @@ pub fn index(&self) -> i32 {
}
/// Gets pointer to an `i2c_adapter` by index.
+ #[inline]
pub fn get(index: i32) -> Result<ARef<Self>> {
// SAFETY: `index` must refer to a valid I2C adapter; the kernel
// guarantees that `i2c_get_adapter(index)` returns either a valid
@@ -416,11 +417,13 @@ pub fn get(index: i32) -> Result<ARef<Self>> {
// SAFETY: Instances of `I2cAdapter` are always reference-counted.
unsafe impl AlwaysRefCounted for I2cAdapter {
+ #[inline]
fn inc_ref(&self) {
// SAFETY: The existence of a shared reference guarantees that the refcount is non-zero.
unsafe { bindings::i2c_get_adapter(self.index()) };
}
+ #[inline]
unsafe fn dec_ref(obj: NonNull<Self>) {
// SAFETY: The safety requirements guarantee that the refcount is non-zero.
unsafe { bindings::i2c_put_adapter(obj.as_ref().as_raw()) }
--
2.53.0