[Intel-gfx] [RFC] drm/i915/hangcheck: Look at instdone for all engines

[Tvrtko Ursulin]

On 10/06/2019 14:05, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2019-06-10 14:01:10)
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> It seems intel_engine_get_instdone is able to get instdone for all engines
>> but intel_hangcheck.c/subunits_stuck decides to ignore it for non render.
>>
>> We can just drop the check in subunits_stuck since the checks on
>> unavailable fields will always return stuck, which when bitwise and with
>> the potential unstuck instdone is harmless.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>> Cc: Chris Wilson <chris at chris-wilson.co.uk>
>> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
>> ---
>> Would actually using the available data improve hang detection?
> 
> No, just prolong it :)

I was thinking activity on instdone would, but correctly so, no? If 
functional blocks have shown a change of status, then we try again until 
they too get stuck. Some improvement in false positives, but marginal I 
know given the hangcheck period.

Regards,

Tvrtko