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Date:   Mon, 30 Oct 2023 13:58:49 +0000
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Subject: Re: [RFC] rust: types: Add read_once and write_once
From:   Alice Ryhl <aliceryhl@google.com>
To:     boqun.feng@gmail.com
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Boqun Feng <boqun.feng@gmail.com> writes:
>> On Wed, Oct 25, 2023 at 09:51:28PM +0000, Benno Lossin wrote:
>>> diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs
>>> index d849e1979ac7..b0872f751f97 100644
>>> --- a/rust/kernel/types.rs
>>> +++ b/rust/kernel/types.rs
>> 
>> I don't think this should go into `types.rs`. But I do not have a good
>> name for the new module.
> 
> kernel::sync?

I think `kernel::sync` is a reasonable choice, but here's another
possibility: Put them in the `bindings` crate.

Why? Well, they are a utility that intends to replicate the C
`READ_ONCE` and `WRITE_ONCE` macros. All of our other methods that do
the same thing for C functions are functions in the bindings crate.

Similarly, if we ever decide to reimplement a C function in Rust for
performance/inlining reasons, then I also think that it is reasonable to
put that Rust-reimplementation in the bindings crate. This approach also
makes it easy to transparently handle cases where we only reimplement a
function in Rust under some configurations.

Alice