68 lines · rust
1// SPDX-License-Identifier: GPL-2.02 3//! Synchronisation primitives.4//!5//! This module contains the kernel APIs related to synchronisation that have been ported or6//! wrapped for usage by Rust code in the kernel.7 8use crate::types::Opaque;9 10mod arc;11mod condvar;12pub mod lock;13mod locked_by;14 15pub use arc::{Arc, ArcBorrow, UniqueArc};16pub use condvar::{new_condvar, CondVar, CondVarTimeoutResult};17pub use lock::mutex::{new_mutex, Mutex};18pub use lock::spinlock::{new_spinlock, SpinLock};19pub use locked_by::LockedBy;20 21/// Represents a lockdep class. It's a wrapper around C's `lock_class_key`.22#[repr(transparent)]23pub struct LockClassKey(Opaque<bindings::lock_class_key>);24 25// SAFETY: `bindings::lock_class_key` is designed to be used concurrently from multiple threads and26// provides its own synchronization.27unsafe impl Sync for LockClassKey {}28 29impl LockClassKey {30 /// Creates a new lock class key.31 pub const fn new() -> Self {32 Self(Opaque::uninit())33 }34 35 pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key {36 self.0.get()37 }38}39 40impl Default for LockClassKey {41 fn default() -> Self {42 Self::new()43 }44}45 46/// Defines a new static lock class and returns a pointer to it.47#[doc(hidden)]48#[macro_export]49macro_rules! static_lock_class {50 () => {{51 static CLASS: $crate::sync::LockClassKey = $crate::sync::LockClassKey::new();52 &CLASS53 }};54}55 56/// Returns the given string, if one is provided, otherwise generates one based on the source code57/// location.58#[doc(hidden)]59#[macro_export]60macro_rules! optional_name {61 () => {62 $crate::c_str!(::core::concat!(::core::file!(), ":", ::core::line!()))63 };64 ($name:literal) => {65 $crate::c_str!($name)66 };67}68