#ifndef _LINUX_NTP_INTERNAL_H#define _LINUX_NTP_INTERNAL_Hexternvoidntp_init(void);externvoidntp_clear(void);/* Returns how long ticks are at present, in ns / 2^NTP_SCALE_SHIFT. */externu64ntp_tick_length(void);externintsecond_overflow(unsignedlongsecs);