diff options
Diffstat (limited to 'include/linux/jiffies.h')
| -rw-r--r-- | include/linux/jiffies.h | 20 |
1 files changed, 3 insertions, 17 deletions
diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h index 05e3c2c7a8cf..6b87413da9d6 100644 --- a/include/linux/jiffies.h +++ b/include/linux/jiffies.h @@ -51,31 +51,17 @@ #define SH_DIV(NOM,DEN,LSH) ( (((NOM) / (DEN)) << (LSH)) \ + ((((NOM) % (DEN)) << (LSH)) + (DEN) / 2) / (DEN)) -#ifdef CLOCK_TICK_RATE /* LATCH is used in the interval timer and ftape setup. */ -# define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */ +#define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */ -/* - * HZ is the requested value. However the CLOCK_TICK_RATE may not allow - * for exactly HZ. So SHIFTED_HZ is high res HZ ("<< 8" is for accuracy) - */ -# define SHIFTED_HZ (SH_DIV(CLOCK_TICK_RATE, LATCH, 8)) -#else -# define SHIFTED_HZ (HZ << 8) -#endif +extern int register_refined_jiffies(long clock_tick_rate); /* TICK_NSEC is the time between ticks in nsec assuming SHIFTED_HZ */ -#define TICK_NSEC (SH_DIV(1000000UL * 1000, SHIFTED_HZ, 8)) +#define TICK_NSEC ((NSEC_PER_SEC+HZ/2)/HZ) /* TICK_USEC is the time between ticks in usec assuming fake USER_HZ */ #define TICK_USEC ((1000000UL + USER_HZ/2) / USER_HZ) -/* - * TICK_USEC_TO_NSEC is the time between ticks in nsec assuming SHIFTED_HZ and - * a value TUSEC for TICK_USEC (can be set bij adjtimex) - */ -#define TICK_USEC_TO_NSEC(TUSEC) (SH_DIV(TUSEC * USER_HZ * 1000, SHIFTED_HZ, 8)) - /* some arch's have a small-data section that can be accessed register-relative * but that can only take up to, say, 4-byte variables. jiffies being part of * an 8-byte variable may not be correctly accessed unless we force the issue |