Comment # 3 on bug 103829 from Chris Wilson

commit 7e07894d8b0f567cb4241b5bed8a9644874ddd47 (HEAD, upstream/master)
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Fri Dec 1 21:53:03 2017 +0000

    igt/gem_busy: Replace arbitrary busy batch with indefinite spinbatch

    In CI, we were observing situations where the busy blt would complete
    before the very next instruction (in userspace) to assert that it was
    busy. This is entirely possible if the process was scheduled away and
    slept for longer than the arbitrary batch. Instead replace arbitrariness
    with a precise infinity.

    v2: Be respectful to UP!
    v3: Move spinbatch to owning process to avoid serialisation delays.

    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103829
    Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
    Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

(Hopefully)