diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/ntp.c | 90 | ||||
| -rw-r--r-- | kernel/time/ntp_internal.h | 7 |
2 files changed, 55 insertions, 42 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 069ca78fb0bf..ff1a7b8ec4ef 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -494,65 +494,55 @@ out: return leap; } +#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) static void sync_hw_clock(struct work_struct *work); -static DECLARE_DELAYED_WORK(sync_work, sync_hw_clock); - -static void sched_sync_hw_clock(struct timespec64 now, - unsigned long target_nsec, bool fail) +static DECLARE_WORK(sync_work, sync_hw_clock); +static struct hrtimer sync_hrtimer; +#define SYNC_PERIOD_NS (11UL * 60 * NSEC_PER_SEC) +static enum hrtimer_restart sync_timer_callback(struct hrtimer *timer) { - struct timespec64 next; + queue_work(system_power_efficient_wq, &sync_work); - ktime_get_real_ts64(&next); - if (!fail) - next.tv_sec = 659; - else { - /* - * Try again as soon as possible. Delaying long periods - * decreases the accuracy of the work queue timer. Due to this - * the algorithm is very likely to require a short-sleep retry - * after the above long sleep to synchronize ts_nsec. - */ - next.tv_sec = 0; - } + return HRTIMER_NORESTART; +} - /* Compute the needed delay that will get to tv_nsec == target_nsec */ - next.tv_nsec = target_nsec - next.tv_nsec; - if (next.tv_nsec <= 0) - next.tv_nsec += NSEC_PER_SEC; - if (next.tv_nsec >= NSEC_PER_SEC) { - next.tv_sec++; - next.tv_nsec -= NSEC_PER_SEC; - } +static void sched_sync_hw_clock(unsigned long offset_nsec, bool retry) +{ + ktime_t exp = ktime_set(ktime_get_real_seconds(), 0); + + if (retry) + exp = ktime_add_ns(exp, 2 * NSEC_PER_SEC - offset_nsec); + else + exp = ktime_add_ns(exp, SYNC_PERIOD_NS - offset_nsec); - queue_delayed_work(system_power_efficient_wq, &sync_work, - timespec64_to_jiffies(&next)); + hrtimer_start(&sync_hrtimer, exp, HRTIMER_MODE_ABS); } static void sync_rtc_clock(void) { - unsigned long target_nsec; - struct timespec64 adjust, now; + unsigned long offset_nsec; + struct timespec64 adjust; int rc; if (!IS_ENABLED(CONFIG_RTC_SYSTOHC)) return; - ktime_get_real_ts64(&now); + ktime_get_real_ts64(&adjust); - adjust = now; if (persistent_clock_is_local) adjust.tv_sec -= (sys_tz.tz_minuteswest * 60); /* - * The current RTC in use will provide the target_nsec it wants to be - * called at, and does rtc_tv_nsec_ok internally. + * The current RTC in use will provide the nanoseconds offset prior + * to a full second it wants to be called at, and invokes + * rtc_tv_nsec_ok() internally. */ - rc = rtc_set_ntp_time(adjust, &target_nsec); + rc = rtc_set_ntp_time(adjust, &offset_nsec); if (rc == -ENODEV) return; - sched_sync_hw_clock(now, target_nsec, rc); + sched_sync_hw_clock(offset_nsec, rc != 0); } #ifdef CONFIG_GENERIC_CMOS_UPDATE @@ -599,7 +589,7 @@ static bool sync_cmos_clock(void) } } - sched_sync_hw_clock(now, target_nsec, rc); + sched_sync_hw_clock(target_nsec, rc != 0); return true; } @@ -613,7 +603,12 @@ static bool sync_cmos_clock(void) */ static void sync_hw_clock(struct work_struct *work) { - if (!ntp_synced()) + /* + * Don't update if STA_UNSYNC is set and if ntp_notify_cmos_timer() + * managed to schedule the work between the timer firing and the + * work being able to rearm the timer. Wait for the timer to expire. + */ + if (!ntp_synced() || hrtimer_is_queued(&sync_hrtimer)) return; if (sync_cmos_clock()) @@ -624,13 +619,23 @@ static void sync_hw_clock(struct work_struct *work) void ntp_notify_cmos_timer(void) { - if (!ntp_synced()) - return; + /* + * When the work is currently executed but has not yet the timer + * rearmed this queues the work immediately again. No big issue, + * just a pointless work scheduled. + */ + if (ntp_synced() && !hrtimer_is_queued(&sync_hrtimer)) + queue_work(system_power_efficient_wq, &sync_work); +} - if (IS_ENABLED(CONFIG_GENERIC_CMOS_UPDATE) || - IS_ENABLED(CONFIG_RTC_SYSTOHC)) - queue_delayed_work(system_power_efficient_wq, &sync_work, 0); +static void __init ntp_init_cmos_sync(void) +{ + hrtimer_init(&sync_hrtimer, CLOCK_REALTIME, HRTIMER_MODE_ABS); + sync_hrtimer.function = sync_timer_callback; } +#else /* CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) */ +static inline void __init ntp_init_cmos_sync(void) { } +#endif /* !CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) */ /* * Propagate a new txc->status value into the NTP state: @@ -1044,4 +1049,5 @@ __setup("ntp_tick_adj=", ntp_tick_adj_setup); void __init ntp_init(void) { ntp_clear(); + ntp_init_cmos_sync(); } diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h index 908ecaa65fc3..23d1b74c3065 100644 --- a/kernel/time/ntp_internal.h +++ b/kernel/time/ntp_internal.h @@ -12,4 +12,11 @@ extern int __do_adjtimex(struct __kernel_timex *txc, const struct timespec64 *ts, s32 *time_tai, struct audit_ntp_data *ad); extern void __hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts); + +#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) +extern void ntp_notify_cmos_timer(void); +#else +static inline void ntp_notify_cmos_timer(void) { } +#endif + #endif /* _LINUX_NTP_INTERNAL_H */ |