@Override
    public void doWork() {
      if (cohort == null) return;
      for (String member : cohort) {
        TestProcedureCoordinator.this.coordinator.memberAcquiredBarrier(opName, member);
      }
    }
Just tell the current coordinator that each of the nodes has prepared
hbase-server/src/test/java/org/apache/hadoop/hbase/procedure/TestProcedureCoordinator.java