[PATCH v5] drm/amdgpu: handle IH ring1 overflow

[Christian König]

Am 24.11.21 um 16:23 schrieb philip yang:
> [SNIP]
>>>   +/**
>>> + * amdgpu_ih_process1 - interrupt handler work for IH ring1
>>> + *
>>> + * @adev: amdgpu_device pointer
>>> + * @ih: ih ring to process
>>> + *
>>> + * Interrupt handler of IH ring1, walk the IH ring1.
>>> + * Returns irq process return code.
>>> + */
>>> +int amdgpu_ih_process1(struct amdgpu_device *adev, struct 
>>> amdgpu_ih_ring *ih)
>>
>> I don't think we need this new function any more.
>>
>> The check if the timestamp goes backwards can now be done inside the 
>> page fault handler.
> Do you mean to merge this into the original ring0 interrupt handler? 
> Then we need add parameter (ih->overflow_enabled) and process two 
> different cases in ring0 interrupt handler, I think that is not good 
> to maintain later so I want to separate them.

What I mean is you don't need any different handling any more if we use 
the timestamp anyway.

Just keep the last processed timestamp in the page fault code and ignore 
faults when it starts to go backwards.

If IVs should be dropped or processed as much as possible is depending 
on quite a bunch of things and should probably not be handled in the IH 
code in general.

Regards,
Christian.