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Date: Mon, 5 Aug 2024 11:07:42 +0200
From: Danilo Krummrich <dakr@kernel.org>
To: Alice Ryhl <aliceryhl@google.com>
Cc: Benno Lossin <benno.lossin@proton.me>, 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>,
	=?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
	Andreas Hindborg <a.hindborg@samsung.com>,
	rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 1/2] rust: kernel: add `drop_contents` to `BoxExt`
Message-ID: <ZrCWXmvCF9L24TdO@pollux>
References: <20240803141639.3237686-1-benno.lossin@proton.me>
 <2ddc08c1-ac38-4cc6-a102-2ad336d6b617@kernel.org>
 <CAH5fLgj2urZ6OD2ki6E=6EuPqW3Z8BGg8jd6Bgo4OOrNiptnDw@mail.gmail.com>
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In-Reply-To: <CAH5fLgj2urZ6OD2ki6E=6EuPqW3Z8BGg8jd6Bgo4OOrNiptnDw@mail.gmail.com>

On Mon, Aug 05, 2024 at 10:43:57AM +0200, Alice Ryhl wrote:
> On Sun, Aug 4, 2024 at 1:22 AM Danilo Krummrich <dakr@kernel.org> wrote:
> >
> > On 8/3/24 4:16 PM, Benno Lossin wrote:
> > > Sometimes (see [1]) it is necessary to drop the value inside of a
> > > `Box<T>`, but retain the allocation. For example to reuse the allocation
> > > in the future.
> > > Introduce a new function `drop_contents` that turns a `Box<T>` into
> > > `Box<MaybeUninit<T>>` by dropping the value.
> >
> > Is this (and the stuff in patch 2) used somewhere? Otherwise, I think it
> > would probably make sense to base this work on top of my allocator work.
> 
> Yes, please see the red/black tree.
> https://lore.kernel.org/rust-for-linux/20240727-b4-rbtree-v8-0-951600ada434@google.com/

Ok, unless preferred otherwise, I'll pick it up in the corresponding patches of
my allocator series then.

> 
> Alice
>