Re: [PATCH v11 08/13] rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`

[Benno Lossin]

On Fri Mar 7, 2025 at 10:38 PM CET, Andreas Hindborg wrote:
> Allow pinned mutable references to structs that contain a `HrTimer` node to
> be scheduled with the `hrtimer` subsystem.
>
> Acked-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
> Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
> Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>

One problem below, with that fixed:

Reviewed-by: Benno Lossin <benno.lossin@xxxxxxxxx>

> ---
>  rust/kernel/time/hrtimer.rs         |   2 +
>  rust/kernel/time/hrtimer/pin_mut.rs | 110 ++++++++++++++++++++++++++++++++++++
>  2 files changed, 112 insertions(+)
>
> diff --git a/rust/kernel/time/hrtimer.rs b/rust/kernel/time/hrtimer.rs
> index fee8e44447ee..ab0950a964e8 100644
> --- a/rust/kernel/time/hrtimer.rs
> +++ b/rust/kernel/time/hrtimer.rs
> @@ -433,3 +433,5 @@ unsafe fn timer_container_of(
>  pub use arc::ArcHrTimerHandle;
>  mod pin;
>  pub use pin::PinHrTimerHandle;
> +mod pin_mut;
> +pub use pin_mut::PinMutHrTimerHandle;
> diff --git a/rust/kernel/time/hrtimer/pin_mut.rs b/rust/kernel/time/hrtimer/pin_mut.rs
> new file mode 100644
> index 000000000000..007f47d26df6
> --- /dev/null
> +++ b/rust/kernel/time/hrtimer/pin_mut.rs
> @@ -0,0 +1,110 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +use super::{
> +    HasHrTimer, HrTimer, HrTimerCallback, HrTimerHandle, RawHrTimerCallback, UnsafeHrTimerPointer,
> +};
> +use crate::time::Ktime;
> +use core::{marker::PhantomData, pin::Pin, ptr::NonNull};
> +
> +/// A handle for a `Pin<&mut HasHrTimer>`. When the handle exists, the timer might
> +/// be running.
> +pub struct PinMutHrTimerHandle<'a, T>
> +where
> +    T: HasHrTimer<T>,
> +{
> +    pub(crate) inner: NonNull<T>,
> +    _p: PhantomData<&'a T>,

This should be `PhantomData<&'a mut T>`.

---
Cheers,
Benno