[Intel-gfx] [PATCH] drm/i915/selftests: Tweak the tolerance for clock ticks to 12.5%

[Alexei Podtelezhnikov]

On Tue, Apr 28, 2020 at 7:43 AM Chris Wilson <chris at chris-wilson.co.uk> wrote:
>
> Give a small bump for our tolerance on comparing the expected vs
> measured clock ticks/time from 10% to 12.5% to accommodate a bad result
> on Sandybridge that was off by 10.3%. Hopefully, that is the worst we
> will see.
> -                       if (10 * time < 9 * ktime_to_ns(dt) ||
> -                           10 * time > 11 * ktime_to_ns(dt)) {
> +                       if (10 * time < 8 * ktime_to_ns(dt) ||
> +                           8 * time > 10 * ktime_to_ns(dt)) {

This is actually -25%/+20% and you could have used 5:4. If your goal
is to cover 10.3% in either direction just barely, use 8:9.