Re: [PATCH v7 1/1] pps: pps-gpio: split IRQ handler into hardirq timestamper + threaded handler

[Rodolfo Giometti <giometti@enneenne.com>]

Hi Andrew,

Could you please pick this patch up for the 7.3 merge window via the -mm tree?

Since the PPS subsystem doesn't have its own dedicated git tree, routing it 
through -mm is the standard path. The patch already has my Acked-by, along with 
all the necessary reviews and test tags.

Thanks,
Rodolfo

On 03/07/2026 20:20, Michael Byczkowski wrote:
> Dear All,
> 
> Now that 7.2-rc1 is out and this didn't make the merge window, could someone please confirm which tree will carry this for 7.3?
> So far, the patch has been:
>      • Reviewed-by: Sebastian Andrzej Siewior (Jun 2)
>      • Acked-by: Rodolfo Giometti (PPS maintainer, from earlier revisions)
>      • Tested-by from Calvin Owens and myself
> 
> I'm not sure whether it should go via drivers/pps (Rodolfo), the rt tree, or -mm. Happy to help route it wherever makes sense.
> lore: https://lore.kernel.org/lkml/79BC1B96-FD2C-4191-8766-6C46BF8A1089@by-online.de/
> 
> Thank you very much and best regards,
> Michael
> 
> 
> 
>> On 3. Jun 2026, at 19:29, Michael Byczkowski <by@by-online.de> wrote:
>>
>> Thank you Sebastian, and thank you Calvin for relaying. I appreciate the
>> thorough review that got this to the right shape.
>>
>> Best regards,
>> Michael
>>
>>
>>> On 2. Jun 2026, at 08:36, Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
>>>
>>> On 2026-06-01 17:44:09 [-0700], Calvin Owens wrote:
>>>> From: Michael Byczkowski <by@by-online.de>
>>>>
>>>> Split the pps-gpio interrupt handler into a primary (hardirq) handler
>>>> that captures the PPS timestamp at interrupt entry, and a threaded
>>>> handler that processes the event. This produces the same two-part
>>>> handler structure on both PREEMPT_RT and non-RT kernels.
>>>>
>>>> On non-RT kernels the threaded portion runs immediately after the
>>>> primary, with no behavioral change compared to the previous
>>>> single-handler implementation.
>>>>
>>>> On PREEMPT_RT, where interrupt handlers are force-threaded by default,
>>>> the previous single-handler implementation captured the timestamp
>>>> inside the threaded portion, after IRQ-thread scheduling delay. With
>>>> the split, the timestamp is captured in true hardirq context as it is
>>>> on non-RT kernels, eliminating a significant source of PPS jitter on
>>>> RT systems.
>>>>
>>>> Tested-by: Michael Byczkowski <by@by-online.de>
>>>> Tested-by: Calvin Owens <calvin@wbinvd.org>
>>>> Acked-by: Rodolfo Giometti <giometti@enneenne.com>
>>>> Signed-off-by: Michael Byczkowski <by@by-online.de>
>>>> Signed-off-by: Calvin Owens <calvin@wbinvd.org>
>>>> ---
>>>
>>> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
>>>
>>> Sebastian
>>
> 


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