Re: [PATCH v8 05/14] rust: hrtimer: allow timer restart from timer handler

From: Andreas Hindborg
Date: Fri Feb 21 2025 - 04:30:49 EST


"Benno Lossin" <benno.lossin@xxxxxxxxx> writes:

> On 18.02.25 14:27, Andreas Hindborg wrote:
>> This patch allows timer handlers to report that they want a timer to be
>> restarted after the timer handler has finished executing.
>>
>> Also update the `hrtimer` documentation to showcase the new feature.
>>
>> Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
>> ---
>> rust/kernel/time/hrtimer.rs | 28 +++++++++++++++++++++++++++-
>> rust/kernel/time/hrtimer/arc.rs | 4 +---
>> 2 files changed, 28 insertions(+), 4 deletions(-)
>>
>> diff --git a/rust/kernel/time/hrtimer.rs b/rust/kernel/time/hrtimer.rs
>> index b2a3130bc21d7..e342193f985eb 100644
>> --- a/rust/kernel/time/hrtimer.rs
>> +++ b/rust/kernel/time/hrtimer.rs
>> @@ -183,7 +183,7 @@ pub trait HrTimerCallback {
>> type CallbackTargetParameter<'a>;
>>
>> /// Called by the timer logic when the timer fires.
>> - fn run(this: Self::CallbackTargetParameter<'_>)
>> + fn run(this: Self::CallbackTargetParameter<'_>) -> HrTimerRestart
>> where
>> Self: Sized;
>> }
>> @@ -278,6 +278,32 @@ unsafe fn start(self_ptr: *const Self, expires: Ktime) {
>> }
>> }
>>
>> +/// Restart policy for timers.
>> +pub enum HrTimerRestart {
>> + /// Timer should not be restarted.
>> + NoRestart,
>> + /// Timer should be restarted.
>> + Restart,
>> +}
>> +
>> +impl From<bindings::hrtimer_restart> for HrTimerRestart {
>> + fn from(value: u32) -> Self {
>> + match value {
>> + bindings::hrtimer_restart_HRTIMER_NORESTART => Self::NoRestart,
>> + _ => Self::Restart,
>> + }
>> + }
>> +}
>> +
>> +impl From<HrTimerRestart> for bindings::hrtimer_restart {
>> + fn from(value: HrTimerRestart) -> Self {
>> + match value {
>> + HrTimerRestart::NoRestart => bindings::hrtimer_restart_HRTIMER_NORESTART,
>> + HrTimerRestart::Restart => bindings::hrtimer_restart_HRTIMER_RESTART,
>> + }
>> + }
>> +}
>
> Do drivers need these impls? If no, I would prefer a private conversion
> function just for the abstraction.

No, drivers would not need these. I can hide them.


Best regards,
Andreas Hindborg