[Intel-gfx] [PATCH i-g-t] kms_rotation_crc: 90 degree flip test is not a stress test

[Tvrtko Ursulin]

On 03/08/2017 13:53, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2017-08-03 13:42:50)
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> To the best of my recollection the page flipping test was added
>> simply to start exercising page flips with 90/270 rotation.
>>
>> There is no need to do 60 flips which can take quite some time
>> because we test each pipe and then each fb geometry. And
>> calling this a stress test is also not matching the original
>> idea of the test.
>>
>> So remove the stress from the name and reduce the number of
>> flips to three only.
> 
> Considering this found a bug, do we have an explicit test that says a
> rotated page flip takes no longer than a vblank (given the right
> conditions, i.e subsequent flips)?

That was just me misremembering how the test work, wasn't a bug. Once I 
looked at the code in more detail I realized the test does much more 
flipping than it initially seemed. Num_pipes * 4 fb geometries * 2 
framebuffers * 60 flips. In total around 8 seconds of flipping per pipe. 
So the 25 second runtime is in line with 3 pipes at 60Hz plus some test 
setup time.

Tvrtko