X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Ftime.c;h=c6324d96009ec20214ce0be3c7e468b5c7679bb1;hb=60d8ce2cd6c283132928c11f3fd57ff4187287e0;hp=4886e3ce83a4d608da8e135a5290fcc8dea4d0cf;hpb=e3d5a27d5862b6425d0879272e24abecf7245105;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/time.c b/kernel/time.c index 4886e3c..c6324d9 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -60,7 +60,7 @@ EXPORT_SYMBOL(sys_tz); * why not move it into the appropriate arch directory (for those * architectures that need it). */ -asmlinkage long sys_time(time_t __user * tloc) +SYSCALL_DEFINE1(time, time_t __user *, tloc) { time_t i = get_seconds(); @@ -79,7 +79,7 @@ asmlinkage long sys_time(time_t __user * tloc) * architectures that need it). */ -asmlinkage long sys_stime(time_t __user *tptr) +SYSCALL_DEFINE1(stime, time_t __user *, tptr) { struct timespec tv; int err; @@ -99,8 +99,8 @@ asmlinkage long sys_stime(time_t __user *tptr) #endif /* __ARCH_WANT_SYS_TIME */ -asmlinkage long sys_gettimeofday(struct timeval __user *tv, - struct timezone __user *tz) +SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv, + struct timezone __user *, tz) { if (likely(tv != NULL)) { struct timeval ktv; @@ -136,7 +136,6 @@ static inline void warp_clock(void) write_seqlock_irq(&xtime_lock); wall_to_monotonic.tv_sec -= sys_tz.tz_minuteswest * 60; xtime.tv_sec += sys_tz.tz_minuteswest * 60; - update_xtime_cache(0); write_sequnlock_irq(&xtime_lock); clock_was_set(); } @@ -184,8 +183,8 @@ int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) return 0; } -asmlinkage long sys_settimeofday(struct timeval __user *tv, - struct timezone __user *tz) +SYSCALL_DEFINE2(settimeofday, struct timeval __user *, tv, + struct timezone __user *, tz) { struct timeval user_tv; struct timespec new_ts; @@ -205,7 +204,7 @@ asmlinkage long sys_settimeofday(struct timeval __user *tv, return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL); } -asmlinkage long sys_adjtimex(struct timex __user *txc_p) +SYSCALL_DEFINE1(adjtimex, struct timex __user *, txc_p) { struct timex txc; /* Local copy of parameter */ int ret; @@ -370,13 +369,20 @@ EXPORT_SYMBOL(mktime); * 0 <= tv_nsec < NSEC_PER_SEC * For negative values only the tv_sec field is negative ! */ -void set_normalized_timespec(struct timespec *ts, time_t sec, long nsec) +void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec) { while (nsec >= NSEC_PER_SEC) { + /* + * The following asm() prevents the compiler from + * optimising this loop into a modulo operation. See + * also __iter_div_u64_rem() in include/linux/time.h + */ + asm("" : "+rm"(nsec)); nsec -= NSEC_PER_SEC; ++sec; } while (nsec < 0) { + asm("" : "+rm"(nsec)); nsec += NSEC_PER_SEC; --sec; } @@ -655,6 +661,36 @@ u64 nsec_to_clock_t(u64 x) #endif } +/** + * nsecs_to_jiffies - Convert nsecs in u64 to jiffies + * + * @n: nsecs in u64 + * + * Unlike {m,u}secs_to_jiffies, type of input is not unsigned int but u64. + * And this doesn't return MAX_JIFFY_OFFSET since this function is designed + * for scheduler, not for use in device drivers to calculate timeout value. + * + * note: + * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) + * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years + */ +unsigned long nsecs_to_jiffies(u64 n) +{ +#if (NSEC_PER_SEC % HZ) == 0 + /* Common case, HZ = 100, 128, 200, 250, 256, 500, 512, 1000 etc. */ + return div_u64(n, NSEC_PER_SEC / HZ); +#elif (HZ % 512) == 0 + /* overflow after 292 years if HZ = 1024 */ + return div_u64(n * HZ / 512, NSEC_PER_SEC / 512); +#else + /* + * Generic case - optimized for cases where HZ is a multiple of 3. + * overflow after 64.99 years, exact for HZ = 60, 72, 90, 120 etc. + */ + return div_u64(n * 9, (9ull * NSEC_PER_SEC + HZ / 2) / HZ); +#endif +} + #if (BITS_PER_LONG < 64) u64 get_jiffies_64(void) {