Received-SPF: pass (google.com: domain of linux-kernel+bounces-130147-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Date: Wed, 03 Apr 2024 15:57:16 +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 3/9] rust: list: add struct with prev/next pointers
Message-ID: <2500d66a-e54e-46d8-97cb-37fd9fc00c45@proton.me>
In-Reply-To: <20240402-linked-list-v1-3-b1c59ba7ae3b@google.com>
References: <20240402-linked-list-v1-0-b1c59ba7ae3b@google.com> <20240402-linked-list-v1-3-b1c59ba7ae3b@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 02.04.24 14:17, Alice Ryhl wrote:
> +/// Implemented by types where a [`ListArc<Self>`] can be inserted into =
a `List`.
> +///
> +/// # Safety
> +///
> +/// Implementers must ensure that they provide the guarantees documented=
 on the three methods
> +/// below.
> +///
> +/// [`ListArc<Self>`]: ListArc
> +pub unsafe trait ListItem<const ID: u64 =3D 0>: ListArcSafe<ID> {
> +    /// Views the [`ListLinks`] for this value.
> +    ///
> +    /// # Guarantees
> +    ///
> +    /// * If there is a currently active call to `prepare_to_insert`, th=
en this returns the same
> +    ///   pointer as the one returned by the currently active call to `p=
repare_to_insert`.

I was a bit confused by the term "active call to `prepare_to_insert`",
since I thought that the function would need to be executed at this
moment. I inferred from below that you mean by this that there has been
a `prepare_to_insert` call, but not yet a corresponding `post_remove`
call.
I did not yet find a better way to phrase this.

I like putting the guarantees on the functions very much.

--=20
Cheers,
Benno