_epoch_enter_preempt
void _epoch_enter_preempt(epoch_t epoch, epoch_tracker_t et EPOCH_FILE_LINE);
#define epoch_enter_preempt(epoch, et) _epoch_enter_preempt(epoch, et, __FILE__, __LINE__)
#define epoch_enter_preempt(epoch, et) _epoch_enter_preempt(epoch, et)