[PATCH i-g-t] tests/kms_setmode: Ignore first timestamp when computing vblank statistics

[Chris Wilson]

Quoting Mika Kahola (2020-05-12 11:48:42)
> kms_setmode is flip flopping due to wondering vblank timestamps. For vblank
> statistics the first timestamp is taken long before we enter to actual loop
> to test vblank accurary.

They are *all* queued ahead of the loop.

> Let's ignore the first timestamp in order to ensure
> that it does not distort the statistics.

No. There's already a vblank wait prior to the start. If you want to
show the skew, show the histogram (ala ministats).
-Chris