extern uint64_t mtime_since_now(struct timeval *);
extern uint64_t time_since_now(struct timeval *);
extern uint64_t mtime_since_genesis(void);
+extern uint64_t utime_since_genesis(void);
extern void usec_spin(unsigned int);
extern void usec_sleep(struct thread_data *, unsigned long);
extern void fill_start_time(struct timeval *);