Re: [PATCH v7 1/9] rust: Introduce atomic API helpers

Greg Kroah-Hartman <[email protected]> Wed, 16 Jul 2025 11:23:09 +0200
Newsgroups dev.linux.lists.lkmm,org.kernel.vger.linux-arch,org.kernel.vger.linux-kernel,org.kernel.vger.rust-for-linux
Message-ID <2025071611-factsheet-sitter-93b6@gregkh>
On Sun, Jul 13, 2025 at 10:36:48PM -0700, Boqun Feng wrote:
> In order to support LKMM atomics in Rust, add rust_helper_* for atomic
> APIs. These helpers ensure the implementation of LKMM atomics in Rust is
> the same as in C. This could save the maintenance burden of having two
> similar atomic implementations in asm.
> 
> Originally-by: Mark Rutland <[email protected]>
> Reviewed-by: Alice Ryhl <[email protected]>
> Signed-off-by: Boqun Feng <[email protected]>
> ---
>  rust/helpers/atomic.c                     | 1040 +++++++++++++++++++++
>  rust/helpers/helpers.c                    |    1 +
>  scripts/atomic/gen-atomics.sh             |    1 +
>  scripts/atomic/gen-rust-atomic-helpers.sh |   67 ++
>  4 files changed, 1109 insertions(+)
>  create mode 100644 rust/helpers/atomic.c
>  create mode 100755 scripts/atomic/gen-rust-atomic-helpers.sh
> 
> diff --git a/rust/helpers/atomic.c b/rust/helpers/atomic.c
> new file mode 100644
> index 000000000000..cf06b7ef9a1c
> --- /dev/null
> +++ b/rust/helpers/atomic.c
> @@ -0,0 +1,1040 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +// Generated by scripts/atomic/gen-rust-atomic-helpers.sh
> +// DO NOT MODIFY THIS FILE DIRECTLY

As this is auto-generated, how do we know when to auto-generate it
again?  What files does it depend on?  And why can't we just
auto-generate it at build time instead of having a static file in the
tree that no one knows when to regenerate it?  :)

thanks,

greg k-h