Automatically try re-enabling TearFree after a flip failed

Specifically, after both the page flip and vblank ioctls failed, but
then the vblank ioctl started working again. This can happen
intermittently e.g. when hotplugging a DP display. Previously, TearFree
would stay disabled in that case until a modeset was triggered somehow.

Reviewed-by: Alex Deucher <>
12 jobs for TearFree-flip-failure-retry in 2 minutes and 9 seconds (queued for 2 seconds)