tree db5957f33b96380f629a13249b3b903f4f701ac9
parent ec194975e46821c5a6198d9486d3aa9be9a83aec
author Chris Wilson <chris@chris-wilson.co.uk> 1468921851 +0100
committer Chris Wilson <chris@chris-wilson.co.uk> 1468921915 +0100

igt/prime_vgem: Replace arbitray delay with backchat from child

Wait until the child tells us they are running (and have verified the
initial buffer state) before modifing the vgem buffer and then signaling
the child.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>