(* MachStep that doesn't change the schedule, Reduces the set of valid schedules... *)
Inductive has_unique_running tp:Prop :=
| HasUniqueRun i (cnti : ThreadPool.containsThread tp i) q:
ThreadPool.getThreadC cnti = Krun q ->
has_unique_running tp.

Lemma ksafe_csafe_equiv:
forall tp m tr,
(forall U, valid (tr, tp, m) U) ->
(forall n U, ksafe_kstep (U, tr, tp) m n) ->
(forall n U, csafe (U, tr, tp) m n).