Re: [PATCH 4/6] rust: hrtimer: Add HrTimerClockBase::time()

[Andreas Hindborg <a.hindborg@kernel.org>]

"Lyude Paul" <lyude@redhat.com> writes:

> This adds a wrapper for the get_time() callback contained within a
> hrtimer_clock_base struct. We'll use this in the next commit in order to
> implement HrTimerCallbackContext::forward_now().
>
> Signed-off-by: Lyude Paul <lyude@redhat.com>
> ---
>  rust/kernel/time/hrtimer.rs | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/rust/kernel/time/hrtimer.rs b/rust/kernel/time/hrtimer.rs
> index f633550882247..521ff1a8a5aa8 100644
> --- a/rust/kernel/time/hrtimer.rs
> +++ b/rust/kernel/time/hrtimer.rs
> @@ -186,6 +186,16 @@ unsafe fn from_raw<'a>(ptr: *mut bindings::hrtimer_clock_base) -> &'a Self {
>          // - Our data layout is equivalent to said struct via our type invariants.
>          unsafe { &*ptr.cast() }
>      }
> +
> +    /// Retrieve the current time from this [`HrTimerClockBase`].
> +    fn time(&self) -> Ktime {
> +        // SAFETY: This callback is initialized to a valid NonNull function for as long as this type
> +        // is exposed to users.

Why is that? Is it by C api contract?


Best regards,
Andreas Hindborg