[igt-dev] [Intel-gfx] [PATCH i-g-t v4] tests/perf_pmu: Avoid RT thread for accuracy test

[Tvrtko Ursulin]

On 11/04/2018 14:23, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2018-04-04 10:51:52)
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> Realtime scheduling interferes with execlists submission (tasklet) so try
>> to simplify the PWM loop in a few ways:
>>
>>   * Drop RT.
>>   * Longer batches for smaller systematic error.
>>   * More truthful test duration calculation.
>>   * Less clock queries.
>>   * No self-adjust - instead just report the achieved cycle and let the
>>     parent check against it.
>>   * Report absolute cycle error.
>>
>> v2:
>>   * Bring back self-adjust. (Chris Wilson)
>>     (But slightly fixed version with no overflow.)
>>
>> v3:
>>   * Log average and mean calibration for each pass.
>>
>> v4:
>>   * Eliminate development leftovers.
>>   * Fix variance logging.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
>  From a pragmatic point of view, there's no point waiting for me to be
> happy with the convergence if CI is, and the variance will definitely be
> interesting (although you could have used igt_mean to compute the
> iterative variance), so
> 
> Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>

Thanks, I've pushed it and so we'll see.

Regards,

Tvrtko