[igt-dev] [Intel-gfx] [PATCH i-g-t] lib/igt_pm: Restore runtime pm state on test exit

[Tvrtko Ursulin]

On 28/02/2018 11:12, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2018-02-28 11:08:29)
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> Some tests (the ones which call igt_setup_runtime_pm and
>> igt_pm_enable_audio_runtime_pm) change default system configuration and
>> never restore it.
>>
>> The configured runtime suspend is aggressive and may influence behaviour
>> of subsequent tests, so it is better to restore to previous values on test
>> exit.
>>
>> This way system behaviour, with regards to a random sequence of executed
>> tests, will be more consistent from one run to another.
> 
> Otoh, if behaviour changes in subsequent tests, we likely have a lack of
> testing :(

Yeah, and I am not saying it does - haven't spotted anything like that, 
just that it leaves the auto-suspend with zero delay afterwards, 
compared to otherwise default 10s.

Maybe it is good for coverage, even with the downside of randomness 
considering shard runs, or maybe it needs to be more explicit.

Regards,

Tvrtko