linux/rust/kernel/sync.rs

// SPDX-License-Identifier: GPL-2.0

//! Synchronisation primitives.
//!
//! This module contains the kernel APIs related to synchronisation that have been ported or
//! wrapped for usage by Rust code in the kernel.

mod arc;

pub use arc::{Arc, ArcBorrow, UniqueArc};
rust: sync: add `Arc` for ref-counted allocations This is a basic implementation of `Arc` backed by C's `refcount_t`. It allows Rust code to idiomatically allocate memory that is ref-counted. Cc: Will Deacon <will@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Acked-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org> 2022-12-28 06:03:40 +00:00			`// SPDX-License-Identifier: GPL-2.0`

			`//! Synchronisation primitives.`
			`//!`
			`//! This module contains the kernel APIs related to synchronisation that have been ported or`
			`//! wrapped for usage by Rust code in the kernel.`

			`mod arc;`

rust: sync: introduce `UniqueArc` Since `Arc<T>` does not allow mutating `T` directly (i.e., without inner mutability), it is currently not possible to do some initialisation of `T` post construction but before being shared. `UniqueArc<T>` addresses this problem essentially being an `Arc<T>` that has a refcount of 1 and is therefore writable. Once initialisation is completed, it can be transitioned (without failure paths) into an `Arc<T>`. Suggested-by: Gary Guo <gary@garyguo.net> Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Acked-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org> 2022-12-28 06:03:45 +00:00			`pub use arc::{Arc, ArcBorrow, UniqueArc};`