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Date: Fri, 14 Jun 2024 21:22:24 +0000
To: Boqun Feng <boqun.feng@gmail.com>, Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
From: Benno Lossin <benno.lossin@proton.me>
Cc: Gary Guo <gary@garyguo.net>, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, llvm@lists.linux.dev, Miguel Ojeda <ojeda@kernel.org>, Alex Gaynor <alex.gaynor@gmail.com>, Wedson Almeida Filho <wedsonaf@gmail.com>, =?utf-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>, Andreas Hindborg <a.hindborg@samsung.com>, Alice Ryhl <aliceryhl@google.com>, Alan Stern <stern@rowland.harvard.edu>, Andrea Parri <parri.andrea@gmail.com>, Will Deacon <will@kernel.org>, Peter Zijlstra <peterz@infradead.org>, Nicholas Piggin <npiggin@gmail.com>, David Howells <dhowells@redhat.com>, Jade Alglave <j.alglave@ucl.ac.uk>, Luc Maranget <luc.maranget@inria.fr>, "Paul E. McKenney" <paulmck@kernel.org>, Akira Yokosawa <akiyks@gmail.com>, Daniel Lustig <dlustig@nvidia.com>, Joel Fernandes <joel@joelfernandes.org>, Nathan Chancellor <nathan@kernel.org>, Nick Desaulniers <ndesaulniers@google.com>, kent.overstreet@gmail.com, Greg Kroah-Hartman
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Subject: Re: [RFC 2/2] rust: sync: Add atomic support
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On 14.06.24 16:33, Boqun Feng wrote:
> On Fri, Jun 14, 2024 at 11:59:58AM +0200, Miguel Ojeda wrote:
>> On Thu, Jun 13, 2024 at 9:05=E2=80=AFPM 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,
>=20
> The truth is I don't know ;-) I don't have much data on which one is
> better. Personally, I think AtomicI32 and AtomicI64 make the users have
> to think about size, alignment, etc, and I think that's important for
> atomic users and people who review their code, because before one uses
> atomics, one should ask themselves: why don't I use a lock? Atomics
> provide the ablities to do low level stuffs and when doing low level
> stuffs, you want to be more explicit than ergonomic.

How would this be different with `Atomic<i32>` and `Atomic<i64>`? Just
because the underlying `Atomic<I>` type is generic shouldn't change
this, right?

---
Cheers,
Benno