code: func (t *Tracer) SetNoop(noop bool) {
  	if noop {
  		atomic.CompareAndSwapInt32(&t.noop, 0, 1)
  	} else {
  		atomic.CompareAndSwapInt32(&t.noop, 1, 0)
  	}
  }
docs: // SetNoop allows for killswitch behavior. If set to true the tracer will return
  // noopSpans and all data is dropped. This allows operators to stop tracing in
  // risk scenarios. Set back to false to resume tracing.