diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs index 33da23e3076d..541d235ffbeb 100644 --- a/rust/kernel/sync.rs +++ b/rust/kernel/sync.rs @@ -5,6 +5,51 @@ //! This module contains the kernel APIs related to synchronisation that have been ported or //! wrapped for usage by Rust code in the kernel. +use crate::types::Opaque; + mod arc; pub use arc::{Arc, ArcBorrow, UniqueArc}; + +/// Represents a lockdep class. It's a wrapper around C's `lock_class_key`. +#[repr(transparent)] +pub struct LockClassKey(Opaque); + +// SAFETY: `bindings::lock_class_key` is designed to be used concurrently from multiple threads and +// provides its own synchronization. +unsafe impl Sync for LockClassKey {} + +impl LockClassKey { + /// Creates a new lock class key. + pub const fn new() -> Self { + Self(Opaque::uninit()) + } + + #[allow(dead_code)] + pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key { + self.0.get() + } +} + +/// Defines a new static lock class and returns a pointer to it. +#[doc(hidden)] +#[macro_export] +macro_rules! static_lock_class { + () => {{ + static CLASS: $crate::sync::LockClassKey = $crate::sync::LockClassKey::new(); + &CLASS + }}; +} + +/// Returns the given string, if one is provided, otherwise generates one based on the source code +/// location. +#[doc(hidden)] +#[macro_export] +macro_rules! optional_name { + () => { + $crate::c_str!(::core::concat!(::core::file!(), ":", ::core::line!())) + }; + ($name:literal) => { + $crate::c_str!($name) + }; +}