Re: [PATCH v4 7/7] drm/i915/gt: Use signalers_lock to prevent starvation of irq_work.

[Maarten Lankhorst]

On 7/9/26 12:57, Sebastian Andrzej Siewior wrote:
> On 2026-07-06 13:48:23 [+0200], Maarten Lankhorst wrote:
>> From: Sebastian Andrzej Siewior <bige...@linutronix.de>
>>
>> IRQ-Work (FIFO-1) will be preempted by the threaded-interrupt (FIFO-50)
>> and the interrupt will poll on signaler_active while the irq-work can't
>> make progress.
>>
>> Solve this by adding a global spinlock to prevent starvation and force
>> completion.
>>
>> The existing RCU handling gets in the way on PREEMPT_RT, and would likely
>> require conversion to raw spinlock to take them inside a
>> rcu_read_lock(), so remove RCU as well.
> 
> You require both locks and a try-lock since the ordering is wrong. And
> you replace the RCU-section with a lock. Understood.
> 
> You probably want to make yourself as the author and make me
> Co-developed-by or something or nothing. This would fix the Sob order
> below.
> 
>> Cc: Sebastian Andrzej Siewior <bige...@linutronix.de>
>> Signed-off-by: Maarten Lankhorst <d...@lankhorst.se>
> 
> Sebastian
Yeah, it seems I missed doing --reset-author when amending here.
It likely needs your sob too if I add you as co author, can I reuse it from the 
original patch?

~Maarten