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Date: Mon, 27 May 2024 10:50:17 +0000
To: Alice Ryhl <aliceryhl@google.com>, Miguel Ojeda <ojeda@kernel.org>, Andrew Morton <akpm@linux-foundation.org>
From: Benno Lossin <benno.lossin@proton.me>
Cc: 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>, Marco Elver <elver@google.com>, Kees Cook <keescook@chromium.org>, Coly Li <colyli@suse.de>, Paolo Abeni <pabeni@redhat.com>, Pierre Gondois <pierre.gondois@arm.com>, Ingo Molnar <mingo@kernel.org>, Jakub Kicinski <kuba@kernel.org>, Wei Yang <richard.weiyang@gmail.com>, Matthew Wilcox <willy@infradead.org>, linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org
Subject: Re: [PATCH v2 9/9] rust: list: add ListArcField
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On 06.05.24 11:53, Alice Ryhl wrote:
> One way to explain what `ListArc` does is that it controls exclusive
> access to the prev/next pointer field in a refcounted object. The
> feature of having a special reference to a refcounted object with
> exclusive access to specific fields is useful for other things, so
> provide a general utility for that.
>=20
> This is used by Rust Binder to keep track of which processes have a
> reference to a given node. This involves an object for each process/node
> pair, that is referenced by both the process and the node. For some
> fields in this object, only the process's reference needs to access
> them (and it needs mutable access), so Binder uses a ListArc to give the
> process's reference exclusive access.
>=20
> Signed-off-by: Alice Ryhl <aliceryhl@google.com>
> ---
>  rust/kernel/list.rs           |  3 ++
>  rust/kernel/list/arc_field.rs | 96 +++++++++++++++++++++++++++++++++++++=
++++++
>  2 files changed, 99 insertions(+)

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

---
Cheers,
Benno