diff options
Diffstat (limited to 'kernel/time/timekeeping.c')
| -rw-r--r-- | kernel/time/timekeeping.c | 117 |
1 files changed, 34 insertions, 83 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 5ce06a3fa91..e424970bb56 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -8,6 +8,7 @@ * */ +#include <linux/timekeeper_internal.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/percpu.h> @@ -21,61 +22,6 @@ #include <linux/tick.h> #include <linux/stop_machine.h> -/* Structure holding internal timekeeping values. */ -struct timekeeper { - /* Current clocksource used for timekeeping. */ - struct clocksource *clock; - /* NTP adjusted clock multiplier */ - u32 mult; - /* The shift value of the current clocksource. */ - u32 shift; - /* Number of clock cycles in one NTP interval. */ - cycle_t cycle_interval; - /* Number of clock shifted nano seconds in one NTP interval. */ - u64 xtime_interval; - /* shifted nano seconds left over when rounding cycle_interval */ - s64 xtime_remainder; - /* Raw nano seconds accumulated per NTP interval. */ - u32 raw_interval; - - /* Current CLOCK_REALTIME time in seconds */ - u64 xtime_sec; - /* Clock shifted nano seconds */ - u64 xtime_nsec; - - /* Difference between accumulated time and NTP time in ntp - * shifted nano seconds. */ - s64 ntp_error; - /* Shift conversion between clock shifted nano seconds and - * ntp shifted nano seconds. */ - u32 ntp_error_shift; - - /* - * wall_to_monotonic is what we need to add to xtime (or xtime corrected - * for sub jiffie times) to get to monotonic time. Monotonic is pegged - * at zero at system boot time, so wall_to_monotonic will be negative, - * however, we will ALWAYS keep the tv_nsec part positive so we can use - * the usual normalization. - * - * wall_to_monotonic is moved after resume from suspend for the - * monotonic time not to jump. We need to add total_sleep_time to - * wall_to_monotonic to get the real boot based time offset. - * - * - wall_to_monotonic is no longer the boot time, getboottime must be - * used instead. - */ - struct timespec wall_to_monotonic; - /* Offset clock monotonic -> clock realtime */ - ktime_t offs_real; - /* time spent in suspend */ - struct timespec total_sleep_time; - /* Offset clock monotonic -> clock boottime */ - ktime_t offs_boot; - /* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */ - struct timespec raw_time; - /* Seqlock for all timekeeper values */ - seqlock_t lock; -}; static struct timekeeper timekeeper; @@ -96,15 +42,6 @@ static inline void tk_normalize_xtime(struct timekeeper *tk) } } -static struct timespec tk_xtime(struct timekeeper *tk) -{ - struct timespec ts; - - ts.tv_sec = tk->xtime_sec; - ts.tv_nsec = (long)(tk->xtime_nsec >> tk->shift); - return ts; -} - static void tk_set_xtime(struct timekeeper *tk, const struct timespec *ts) { tk->xtime_sec = ts->tv_sec; @@ -246,14 +183,11 @@ static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk) /* must hold write on timekeeper.lock */ static void timekeeping_update(struct timekeeper *tk, bool clearntp) { - struct timespec xt; - if (clearntp) { tk->ntp_error = 0; ntp_clear(); } - xt = tk_xtime(tk); - update_vsyscall(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult); + update_vsyscall(tk); } /** @@ -1113,7 +1047,7 @@ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, accumulate_nsecs_to_secs(tk); /* Accumulate raw time */ - raw_nsecs = tk->raw_interval << shift; + raw_nsecs = (u64)tk->raw_interval << shift; raw_nsecs += tk->raw_time.tv_nsec; if (raw_nsecs >= NSEC_PER_SEC) { u64 raw_secs = raw_nsecs; @@ -1130,6 +1064,33 @@ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, return offset; } +#ifdef CONFIG_GENERIC_TIME_VSYSCALL_OLD +static inline void old_vsyscall_fixup(struct timekeeper *tk) +{ + s64 remainder; + + /* + * Store only full nanoseconds into xtime_nsec after rounding + * it up and add the remainder to the error difference. + * XXX - This is necessary to avoid small 1ns inconsistnecies caused + * by truncating the remainder in vsyscalls. However, it causes + * additional work to be done in timekeeping_adjust(). Once + * the vsyscall implementations are converted to use xtime_nsec + * (shifted nanoseconds), and CONFIG_GENERIC_TIME_VSYSCALL_OLD + * users are removed, this can be killed. + */ + remainder = tk->xtime_nsec & ((1ULL << tk->shift) - 1); + tk->xtime_nsec -= remainder; + tk->xtime_nsec += 1ULL << tk->shift; + tk->ntp_error += remainder << tk->ntp_error_shift; + +} +#else +#define old_vsyscall_fixup(tk) +#endif + + + /** * update_wall_time - Uses the current clocksource to increment the wall time * @@ -1141,7 +1102,6 @@ static void update_wall_time(void) cycle_t offset; int shift = 0, maxshift; unsigned long flags; - s64 remainder; write_seqlock_irqsave(&tk->lock, flags); @@ -1183,20 +1143,11 @@ static void update_wall_time(void) /* correct the clock when NTP error is too big */ timekeeping_adjust(tk, offset); - /* - * Store only full nanoseconds into xtime_nsec after rounding - * it up and add the remainder to the error difference. - * XXX - This is necessary to avoid small 1ns inconsistnecies caused - * by truncating the remainder in vsyscalls. However, it causes - * additional work to be done in timekeeping_adjust(). Once - * the vsyscall implementations are converted to use xtime_nsec - * (shifted nanoseconds), this can be killed. - */ - remainder = tk->xtime_nsec & ((1ULL << tk->shift) - 1); - tk->xtime_nsec -= remainder; - tk->xtime_nsec += 1ULL << tk->shift; - tk->ntp_error += remainder << tk->ntp_error_shift; + * XXX This can be killed once everyone converts + * to the new update_vsyscall. + */ + old_vsyscall_fixup(tk); /* * Finally, make sure that after the rounding |