Re: [PATCH v8 3/9] rust: sync: atomic: Add ordering annotation types

On Sat Jul 19, 2025 at 5:08 AM CEST, Boqun Feng wrote:
> Preparation for atomic primitives. Instead of a suffix like _acquire, a
> method parameter along with the corresponding generic parameter will be
> used to specify the ordering of an atomic operations. For example,
> atomic load() can be defined as:
>
> 	impl<T: ...> Atomic<T> {
> 	    pub fn load<O: AcquireOrRelaxed>(&self, _o: O) -> T { ... }
> 	}
>
> and acquire users would do:
>
> 	let r = x.load(Acquire);
>
> relaxed users:
>
> 	let r = x.load(Relaxed);
>
> doing the following:
>
> 	let r = x.load(Release);
>
> will cause a compiler error.
>
> Compared to suffixes, it's easier to tell what ordering variants an
> operation has, and it also make it easier to unify the implementation of
> all ordering variants in one method via generic. The `TYPE` associate
> const is for generic function to pick up the particular implementation
> specified by an ordering annotation.
>
> Reviewed-by: Alice Ryhl <[email protected]>
> Signed-off-by: Boqun Feng <[email protected]>

Reviewed-by: Benno Lossin <[email protected]>

---
Cheers,
Benno

> ---
>  rust/kernel/sync/atomic.rs          |   2 +
>  rust/kernel/sync/atomic/ordering.rs | 104 ++++++++++++++++++++++++++++
>  2 files changed, 106 insertions(+)
>  create mode 100644 rust/kernel/sync/atomic/ordering.rs