The motivation for relative adjustment is when you have a jitterSince we added the padding you asked for, we could use that bit of information
resistant place to gather timing information (like the kernel, which can
disable interrupts and preemption), then pass it on to kvm without
losing information due to scheduling. For migration there is no such
place since it involves two hosts, but it makes sense to support
relative adjustments.
to define whether it will be a relative or absolute adjustment, then. Right now,
I don't see the point of implementing a code path that will be completely untested.
I'd leave it this way until someone comes up with a need.