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Date: Fri, 14 Jun 2024 18:03:37 -0700
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Subject: Re: [RFC 2/2] rust: sync: Add atomic support
To: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>, Boqun Feng
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From: John Hubbard <jhubbard@nvidia.com>
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On 6/14/24 2:59 AM, Miguel Ojeda wrote:
> On Thu, Jun 13, 2024 at 9:05 PM Boqun Feng <boqun.feng@gmail.com> wrote:
>>
>> Does this make sense?
> 
> Implementation-wise, if you think it is simpler or more clear/elegant
> to have the extra lower level layer, then that sounds fine.
> 
> However, I was mainly talking about what we would eventually expose to
> users, i.e. do we want to provide `Atomic<T>` to begin with? If yes,
> then we could make the lower layer private already.
> 
> We can defer that extra layer/work if needed even if we go for
> `Atomic<T>`, but it would be nice to understand if we have consensus
> for an eventual user-facing API, or if someone has any other opinion
> or concerns on one vs. the other.

Well, here's one:

The reason that we have things like atomic64_read() in the C code is
because C doesn't have generics.

In Rust, we should simply move directly to Atomic<T>, as there are,
after all, associated benefits. And it's very easy to see the connection
between the C types and the Atomic<T> types.


thanks,
-- 
John Hubbard
NVIDIA