[PATCH v4 1/2] rust: add static_key_false

[Gary Guo]

On Fri, 28 Jun 2024 13:23:31 +0000
Alice Ryhl <aliceryhl at google.com> wrote:

> Add just enough support for static key so that we can use it from
> tracepoints. Tracepoints rely on `static_key_false` even though it is
> deprecated, so we add the same functionality to Rust.
> 
> It is not possible to use the existing C implementation of
> arch_static_branch because it passes the argument `key` to inline
> assembly as an 'i' parameter, so any attempt to add a C helper for this
> function will fail to compile because the value of `key` must be known
> at compile-time.
> 
> Signed-off-by: Alice Ryhl <aliceryhl at google.com>

Reviewed-by: Gary Guo <gary at garyguo.net>

> ---
>  rust/kernel/arch/arm64/jump_label.rs     | 34 ++++++++++++++++++++++++++++
>  rust/kernel/arch/loongarch/jump_label.rs | 35 +++++++++++++++++++++++++++++
>  rust/kernel/arch/mod.rs                  | 24 ++++++++++++++++++++
>  rust/kernel/arch/riscv/jump_label.rs     | 38 ++++++++++++++++++++++++++++++++
>  rust/kernel/arch/x86/jump_label.rs       | 35 +++++++++++++++++++++++++++++
>  rust/kernel/lib.rs                       |  2 ++
>  rust/kernel/static_key.rs                | 32 +++++++++++++++++++++++++++
>  scripts/Makefile.build                   |  2 +-
>  8 files changed, 201 insertions(+), 1 deletion(-)