Re: [PATCH 2/2] samples: rust: add in-place initialisation sample

From: Benno Lossin
Date: Wed Mar 27 2024 - 10:55:59 EST


On 27.03.24 04:23, Wedson Almeida Filho wrote:
> diff --git a/samples/rust/rust_inplace.rs b/samples/rust/rust_inplace.rs
> new file mode 100644
> index 000000000000..ba8d051cac56
> --- /dev/null
> +++ b/samples/rust/rust_inplace.rs
> @@ -0,0 +1,42 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +//! Rust minimal in-place sample.
> +
> +use kernel::prelude::*;
> +
> +module! {
> + type: RustInPlace,
> + name: "rust_inplace",
> + author: "Rust for Linux Contributors",
> + description: "Rust minimal in-place sample",
> + license: "GPL",
> +}
> +
> +#[pin_data(PinnedDrop)]
> +struct RustInPlace {
> + numbers: Vec<i32>,
> +}
> +
> +impl kernel::InPlaceModule for RustInPlace {
> + fn init(_module: &'static ThisModule) -> impl PinInit<Self, Error> {
> + pr_info!("Rust minimal sample (init)\n");

This text needs updating.

> + pr_info!("Am I built-in? {}\n", !cfg!(MODULE));
> + try_pin_init!(Self {
> + numbers: {
> + let mut numbers = Vec::new();
> + numbers.push(72, GFP_KERNEL)?;
> + numbers.push(108, GFP_KERNEL)?;
> + numbers.push(200, GFP_KERNEL)?;
> + numbers
> + },
> + })

I think it might be useful to also have a field that needs pin-init, eg
a `Mutex` or similar. What about placing the `Vec` inside of a mutex?

--
Cheers,
Benno

> + }
> +}
> +
> +#[pinned_drop]
> +impl PinnedDrop for RustInPlace {
> + fn drop(self: Pin<&mut Self>) {
> + pr_info!("My numbers are {:?}\n", self.numbers);
> + pr_info!("Rust minimal inplace sample (exit)\n");
> + }
> +}
> --
> 2.34.1
>