diff options
Diffstat (limited to 'kernel/time.c')
| -rw-r--r-- | kernel/time.c | 70 |
1 files changed, 37 insertions, 33 deletions
diff --git a/kernel/time.c b/kernel/time.c index 32174359576..7c7964c33ae 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -11,7 +11,7 @@ * Modification history kernel/time.c * * 1993-09-02 Philip Gladstone - * Created file with time related functions from sched.c and adjtimex() + * Created file with time related functions from sched/core.c and adjtimex() * 1993-10-08 Torsten Duwe * adjtime interface update and CMOS clock write code * 1995-08-13 Torsten Duwe @@ -27,10 +27,10 @@ * with nanosecond accuracy */ -#include <linux/module.h> +#include <linux/export.h> #include <linux/timex.h> #include <linux/capability.h> -#include <linux/clocksource.h> +#include <linux/timekeeper_internal.h> #include <linux/errno.h> #include <linux/syscalls.h> #include <linux/security.h> @@ -115,6 +115,12 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv, } /* + * Indicates if there is an offset between the system clock and the hardware + * clock/persistent clock/rtc. + */ +int persistent_clock_is_local; + +/* * Adjust the time obtained from the CMOS to be UTC time instead of * local time. * @@ -132,11 +138,14 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv, */ static inline void warp_clock(void) { - struct timespec adjust; + if (sys_tz.tz_minuteswest != 0) { + struct timespec adjust; - adjust = current_kernel_time(); - adjust.tv_sec += sys_tz.tz_minuteswest * 60; - do_settimeofday(&adjust); + persistent_clock_is_local = 1; + adjust.tv_sec = sys_tz.tz_minuteswest * 60; + adjust.tv_nsec = 0; + timekeeping_inject_offset(&adjust); + } } /* @@ -150,7 +159,7 @@ static inline void warp_clock(void) * various programs will get confused when the clock gets warped. */ -int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) +int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz) { static int firsttime = 1; int error = 0; @@ -163,7 +172,6 @@ int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) return error; if (tz) { - /* SMP safe, global irq locking makes it work. */ sys_tz = *tz; update_vsyscall_tz(); if (firsttime) { @@ -173,12 +181,7 @@ int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) } } if (tv) - { - /* SMP safe, again the code in arch/foo/time.c should - * globally block out interrupts when it runs. - */ return do_settimeofday(tv); - } return 0; } @@ -238,7 +241,7 @@ EXPORT_SYMBOL(current_fs_time); * Avoid unnecessary multiplications/divisions in the * two most common HZ cases: */ -inline unsigned int jiffies_to_msecs(const unsigned long j) +unsigned int jiffies_to_msecs(const unsigned long j) { #if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) return (MSEC_PER_SEC / HZ) * j; @@ -254,7 +257,7 @@ inline unsigned int jiffies_to_msecs(const unsigned long j) } EXPORT_SYMBOL(jiffies_to_msecs); -inline unsigned int jiffies_to_usecs(const unsigned long j) +unsigned int jiffies_to_usecs(const unsigned long j) { #if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) return (USEC_PER_SEC / HZ) * j; @@ -575,7 +578,7 @@ EXPORT_SYMBOL(jiffies_to_timeval); /* * Convert jiffies/jiffies_64 to clock_t and back. */ -clock_t jiffies_to_clock_t(long x) +clock_t jiffies_to_clock_t(unsigned long x) { #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 # if HZ < USER_HZ @@ -645,7 +648,7 @@ u64 nsec_to_clock_t(u64 x) } /** - * nsecs_to_jiffies - Convert nsecs in u64 to jiffies + * nsecs_to_jiffies64 - Convert nsecs in u64 to jiffies64 * * @n: nsecs in u64 * @@ -657,7 +660,7 @@ u64 nsec_to_clock_t(u64 x) * 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) +u64 nsecs_to_jiffies64(u64 n) { #if (NSEC_PER_SEC % HZ) == 0 /* Common case, HZ = 100, 128, 200, 250, 256, 500, 512, 1000 etc. */ @@ -674,22 +677,23 @@ unsigned long nsecs_to_jiffies(u64 n) #endif } -#if (BITS_PER_LONG < 64) -u64 get_jiffies_64(void) +/** + * 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) { - unsigned long seq; - u64 ret; - - do { - seq = read_seqbegin(&xtime_lock); - ret = jiffies_64; - } while (read_seqretry(&xtime_lock, seq)); - return ret; + return (unsigned long)nsecs_to_jiffies64(n); } -EXPORT_SYMBOL(get_jiffies_64); -#endif - -EXPORT_SYMBOL(jiffies); /* * Add two timespec values and do a safety check for overflow. |