Enable extra debug warnings for vblank evasion

configname: CONFIG_DRM_I915_DEBUG_VBLANK_EVADE

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>drm/i915 Debugging
└─>Enable extra debug warnings for vblank evasion
In linux kernel since version 4.2 (release Date: 2015-08-30)  
Choose this option to turn on extra debug warnings for the
vblank evade mechanism. This gives a warning every time the
the deadline allotted for the vblank evade critical section
is exceeded, even if there isn't an actual risk of missing
the vblank.

Recommended for driver developers only.

If in doubt, say "N".

depends
CONFIG_DRM_I915
CONFIG_EXPERT
CONFIG_HAS_IOMEM