Re: [PATCH] rust: hrtimer: add active() method to query timer state

From: Gary Guo

Date: Fri Feb 27 2026 - 09:40:30 EST


On Sun Feb 15, 2026 at 8:29 PM GMT, Andreas Hindborg wrote:
> Add an `active()` method to HrTimer that returns true if the timer is in
> the started or running states. This wraps the kernel's hrtimer_active()
> function.
>
> Also add documentation clarifying the definition of an active timer.
>
> Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
> ---
> 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 856d2d929a008..b2272b059e504 100644
> --- a/rust/kernel/time/hrtimer.rs
> +++ b/rust/kernel/time/hrtimer.rs
> @@ -66,6 +66,8 @@
> //!
> //! A `restart` operation on a timer in the **stopped** state is equivalent to a
> //! `start` operation.
> +//!
> +//! A timer is **active** if it is either in the **started** or **running** states.
>
> use super::{ClockSource, Delta, Instant};
> use crate::{prelude::*, types::Opaque};
> @@ -246,6 +248,14 @@ pub fn expires(&self) -> HrTimerInstant<T>
> )
> }
> }
> +
> + /// Query the state of the timer.
> + ///
> + /// Returns `true` if the timer is in the started or running states.

This could be `#[inline]`.

> + pub fn active(&self) -> bool {
> + // SAFETY: By type invariant, `self.timer` is valid.

Perhaps also mention that this function is safe to call without exclusive
requirement, as this is a common requiremnt for many other hrtimer functions.

Best,
Gary

> + unsafe { bindings::hrtimer_active(self.timer.get()) }
> + }
> }
>
> /// Implemented by pointer types that point to structs that contain a [`HrTimer`].
>
> ---
> base-commit: 05f7e89ab9731565d8a62e3b5d1ec206485eeb0b
> change-id: 20260215-hrtimer-active-f183411fe56b
>
> Best regards,