Received-SPF: pass (google.com: domain of linux-kernel+bounces-4211-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Date: Mon, 18 Dec 2023 17:45:54 +0000
To: Alice Ryhl <aliceryhl@google.com>, Miguel Ojeda <ojeda@kernel.org>, Alex Gaynor <alex.gaynor@gmail.com>, Wedson Almeida Filho <wedsonaf@gmail.com>, Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>, =?utf-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>, Andreas Hindborg <a.hindborg@samsung.com>, Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>, Waiman Long <longman@redhat.com>, Tiago Lam <tiagolam@gmail.com>, Thomas Gleixner <tglx@linutronix.de>
From: Benno Lossin <benno.lossin@proton.me>
Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 4/4] rust: sync: update integer types in CondVar
Message-ID: <caefaf00-bf59-4ad9-bec5-9d095754354c@proton.me>
In-Reply-To: <20231216-rb-new-condvar-methods-v2-4-b05ab61e6d5b@google.com>
References: <20231216-rb-new-condvar-methods-v2-0-b05ab61e6d5b@google.com> <20231216-rb-new-condvar-methods-v2-4-b05ab61e6d5b@google.com>
Feedback-ID: 71780778:user:proton
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable

On 12/16/23 16:31, Alice Ryhl wrote:
> Reduce the chances of compilation failures due to integer type
> mismatches in `CondVar`.
>=20
> When an integer is defined using a #define in C, bindgen doesn't know
> which integer type it is supposed to be, so it will just use `u32` by
> default (if it fits in an u32). Whenever the right type is something
> else, we insert a cast in Rust. However, this means that the code has a
> lot of extra casts, and sometimes the code will be missing casts if u32
> happens to be correct on the developer's machine, even though the type
> might be something else on a different platform.
>=20
> This patch updates all uses of such constants in
> `rust/kernel/sync/condvar.rs` to use constants defined with the right
> type. This allows us to remove various unnecessary casts, while also
> future-proofing for the case where `unsigned int !=3D u32`.
>=20
> I wrote this patch at the suggestion of Benno in [1].
>=20
> Link: https://lore.kernel.org/all/nAEg-6vbtX72ZY3oirDhrSEf06TBWmMiTt73Ekl=
MzEAzN4FD4mF3TPEyAOxBZgZtjzoiaBYtYr3s8sa9wp1uYH9vEWRf2M-Lf4I0BY9rAgk=3D@pro=
ton.me/ [1]
> Suggested-by: Benno Lossin <benno.lossin@proton.me>
> Signed-off-by: Alice Ryhl <aliceryhl@google.com>
> ---

Reviewed-by: Benno Lossin <benno.lossin@proton.me>

--=20
Cheers,
Benno