FYI I've tested this series using your 'preemption' branch on KBL and
'egl-context-priority' test passes. The other Piglit test I sent
('egl-context-priority-runtime') does not always pass but I think the
problem is actually in the test itself, it's making assumptions that are
not true. I will
IMG_context_priority
https://www.khronos.org/registry/egl/extensions/IMG/EGL_IMG_context_priority.txt
"This extension allows an EGLContext to be created with a priority
hint. It is possible that an implementation will not honour the
hint, especially if there are constraints on the numb
