diff options
Diffstat (limited to 'kernel/time')
-rw-r--r-- | kernel/time/ntp.c | 105 | ||||
-rw-r--r-- | kernel/time/ntp_internal.h | 12 | ||||
-rw-r--r-- | kernel/time/tick-broadcast.c | 235 | ||||
-rw-r--r-- | kernel/time/tick-common.c | 1 | ||||
-rw-r--r-- | kernel/time/tick-internal.h | 5 | ||||
-rw-r--r-- | kernel/time/tick-sched.c | 4 | ||||
-rw-r--r-- | kernel/time/timekeeping.c | 396 | ||||
-rw-r--r-- | kernel/time/timer_list.c | 104 |
8 files changed, 629 insertions, 233 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 072bb066bb7d..12ff13a838c6 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -18,13 +18,14 @@ #include <linux/rtc.h> #include "tick-internal.h" +#include "ntp_internal.h" /* * NTP timekeeping variables: + * + * Note: All of the NTP state is protected by the timekeeping locks. */ -DEFINE_RAW_SPINLOCK(ntp_lock); - /* USER_HZ period (usecs): */ unsigned long tick_usec = TICK_USEC; @@ -53,9 +54,6 @@ static int time_state = TIME_OK; /* clock status bits: */ static int time_status = STA_UNSYNC; -/* TAI offset (secs): */ -static long time_tai; - /* time adjustment (nsecs): */ static s64 time_offset; @@ -134,8 +132,6 @@ static inline void pps_reset_freq_interval(void) /** * pps_clear - Clears the PPS state variables - * - * Must be called while holding a write on the ntp_lock */ static inline void pps_clear(void) { @@ -150,8 +146,6 @@ static inline void pps_clear(void) /* Decrease pps_valid to indicate that another second has passed since * the last PPS signal. When it reaches 0, indicate that PPS signal is * missing. - * - * Must be called while holding a write on the ntp_lock */ static inline void pps_dec_valid(void) { @@ -346,10 +340,6 @@ static void ntp_update_offset(long offset) */ void ntp_clear(void) { - unsigned long flags; - - raw_spin_lock_irqsave(&ntp_lock, flags); - time_adjust = 0; /* stop active adjtime() */ time_status |= STA_UNSYNC; time_maxerror = NTP_PHASE_LIMIT; @@ -362,20 +352,12 @@ void ntp_clear(void) /* Clear PPS state variables */ pps_clear(); - raw_spin_unlock_irqrestore(&ntp_lock, flags); - } u64 ntp_tick_length(void) { - unsigned long flags; - s64 ret; - - raw_spin_lock_irqsave(&ntp_lock, flags); - ret = tick_length; - raw_spin_unlock_irqrestore(&ntp_lock, flags); - return ret; + return tick_length; } @@ -393,9 +375,6 @@ int second_overflow(unsigned long secs) { s64 delta; int leap = 0; - unsigned long flags; - - raw_spin_lock_irqsave(&ntp_lock, flags); /* * Leap second processing. If in leap-insert state at the end of the @@ -415,7 +394,6 @@ int second_overflow(unsigned long secs) else if (secs % 86400 == 0) { leap = -1; time_state = TIME_OOP; - time_tai++; printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n"); } @@ -425,7 +403,6 @@ int second_overflow(unsigned long secs) time_state = TIME_OK; else if ((secs + 1) % 86400 == 0) { leap = 1; - time_tai--; time_state = TIME_WAIT; printk(KERN_NOTICE "Clock: deleting leap second 23:59:59 UTC\n"); @@ -479,8 +456,6 @@ int second_overflow(unsigned long secs) time_adjust = 0; out: - raw_spin_unlock_irqrestore(&ntp_lock, flags); - return leap; } @@ -575,11 +550,10 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts) time_status |= txc->status & ~STA_RONLY; } -/* - * Called with ntp_lock held, so we can access and modify - * all the global NTP state: - */ -static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts) + +static inline void process_adjtimex_modes(struct timex *txc, + struct timespec *ts, + s32 *time_tai) { if (txc->modes & ADJ_STATUS) process_adj_status(txc, ts); @@ -613,7 +587,7 @@ static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts } if (txc->modes & ADJ_TAI && txc->constant > 0) - time_tai = txc->constant; + *time_tai = txc->constant; if (txc->modes & ADJ_OFFSET) ntp_update_offset(txc->offset); @@ -625,16 +599,13 @@ static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts ntp_update_frequency(); } -/* - * adjtimex mainly allows reading (and writing, if superuser) of - * kernel time-keeping variables. used by xntpd. + + +/** + * ntp_validate_timex - Ensures the timex is ok for use in do_adjtimex */ -int do_adjtimex(struct timex *txc) +int ntp_validate_timex(struct timex *txc) { - struct timespec ts; - int result; - - /* Validate the data before disabling interrupts */ if (txc->modes & ADJ_ADJTIME) { /* singleshot must not be used with any other mode bits */ if (!(txc->modes & ADJ_OFFSET_SINGLESHOT)) @@ -646,7 +617,6 @@ int do_adjtimex(struct timex *txc) /* In order to modify anything, you gotta be super-user! */ if (txc->modes && !capable(CAP_SYS_TIME)) return -EPERM; - /* * if the quartz is off by more than 10% then * something is VERY wrong! @@ -657,22 +627,20 @@ int do_adjtimex(struct timex *txc) return -EINVAL; } - if (txc->modes & ADJ_SETOFFSET) { - struct timespec delta; - delta.tv_sec = txc->time.tv_sec; - delta.tv_nsec = txc->time.tv_usec; - if (!capable(CAP_SYS_TIME)) - return -EPERM; - if (!(txc->modes & ADJ_NANO)) - delta.tv_nsec *= 1000; - result = timekeeping_inject_offset(&delta); - if (result) - return result; - } + if ((txc->modes & ADJ_SETOFFSET) && (!capable(CAP_SYS_TIME))) + return -EPERM; - getnstimeofday(&ts); + return 0; +} - raw_spin_lock_irq(&ntp_lock); + +/* + * adjtimex mainly allows reading (and writing, if superuser) of + * kernel time-keeping variables. used by xntpd. + */ +int __do_adjtimex(struct timex *txc, struct timespec *ts, s32 *time_tai) +{ + int result; if (txc->modes & ADJ_ADJTIME) { long save_adjust = time_adjust; @@ -687,7 +655,7 @@ int do_adjtimex(struct timex *txc) /* If there are input parameters, then process them: */ if (txc->modes) - process_adjtimex_modes(txc, &ts); + process_adjtimex_modes(txc, ts, time_tai); txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, NTP_SCALE_SHIFT); @@ -709,15 +677,13 @@ int do_adjtimex(struct timex *txc) txc->precision = 1; txc->tolerance = MAXFREQ_SCALED / PPM_SCALE; txc->tick = tick_usec; - txc->tai = time_tai; + txc->tai = *time_tai; /* fill PPS status fields */ pps_fill_timex(txc); - raw_spin_unlock_irq(&ntp_lock); - - txc->time.tv_sec = ts.tv_sec; - txc->time.tv_usec = ts.tv_nsec; + txc->time.tv_sec = ts->tv_sec; + txc->time.tv_usec = ts->tv_nsec; if (!(time_status & STA_NANO)) txc->time.tv_usec /= NSEC_PER_USEC; @@ -894,7 +860,7 @@ static void hardpps_update_phase(long error) } /* - * hardpps() - discipline CPU clock oscillator to external PPS signal + * __hardpps() - discipline CPU clock oscillator to external PPS signal * * This routine is called at each PPS signal arrival in order to * discipline the CPU clock oscillator to the PPS signal. It takes two @@ -905,15 +871,13 @@ static void hardpps_update_phase(long error) * This code is based on David Mills's reference nanokernel * implementation. It was mostly rewritten but keeps the same idea. */ -void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) +void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) { struct pps_normtime pts_norm, freq_norm; unsigned long flags; pts_norm = pps_normalize_ts(*phase_ts); - raw_spin_lock_irqsave(&ntp_lock, flags); - /* clear the error bits, they will be set again if needed */ time_status &= ~(STA_PPSJITTER | STA_PPSWANDER | STA_PPSERROR); @@ -925,7 +889,6 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) * just start the frequency interval */ if (unlikely(pps_fbase.tv_sec == 0)) { pps_fbase = *raw_ts; - raw_spin_unlock_irqrestore(&ntp_lock, flags); return; } @@ -940,7 +903,6 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) time_status |= STA_PPSJITTER; /* restart the frequency calibration interval */ pps_fbase = *raw_ts; - raw_spin_unlock_irqrestore(&ntp_lock, flags); pr_err("hardpps: PPSJITTER: bad pulse\n"); return; } @@ -957,10 +919,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) hardpps_update_phase(pts_norm.nsec); - raw_spin_unlock_irqrestore(&ntp_lock, flags); } -EXPORT_SYMBOL(hardpps); - #endif /* CONFIG_NTP_PPS */ static int __init ntp_tick_adj_setup(char *str) diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h new file mode 100644 index 000000000000..1950cb4ca2a4 --- /dev/null +++ b/kernel/time/ntp_internal.h @@ -0,0 +1,12 @@ +#ifndef _LINUX_NTP_INTERNAL_H +#define _LINUX_NTP_INTERNAL_H + +extern void ntp_init(void); +extern void ntp_clear(void); +/* Returns how long ticks are at present, in ns / 2^NTP_SCALE_SHIFT. */ +extern u64 ntp_tick_length(void); +extern int second_overflow(unsigned long secs); +extern int ntp_validate_timex(struct timex *); +extern int __do_adjtimex(struct timex *, struct timespec *, s32 *); +extern void __hardpps(const struct timespec *, const struct timespec *); +#endif /* _LINUX_NTP_INTERNAL_H */ diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 7f32fe0e52cd..6e23fde83dbe 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -28,9 +28,8 @@ */ static struct tick_device tick_broadcast_device; -/* FIXME: Use cpumask_var_t. */ -static DECLARE_BITMAP(tick_broadcast_mask, NR_CPUS); -static DECLARE_BITMAP(tmpmask, NR_CPUS); +static cpumask_var_t tick_broadcast_mask; +static cpumask_var_t tmpmask; static DEFINE_RAW_SPINLOCK(tick_broadcast_lock); static int tick_broadcast_force; @@ -50,7 +49,7 @@ struct tick_device *tick_get_broadcast_device(void) struct cpumask *tick_get_broadcast_mask(void) { - return to_cpumask(tick_broadcast_mask); + return tick_broadcast_mask; } /* @@ -75,8 +74,18 @@ int tick_check_broadcast_device(struct clock_event_device *dev) clockevents_exchange_device(tick_broadcast_device.evtdev, dev); tick_broadcast_device.evtdev = dev; - if (!cpumask_empty(tick_get_broadcast_mask())) + if (!cpumask_empty(tick_broadcast_mask)) tick_broadcast_start_periodic(dev); + /* + * Inform all cpus about this. We might be in a situation + * where we did not switch to oneshot mode because the per cpu + * devices are affected by CLOCK_EVT_FEAT_C3STOP and the lack + * of a oneshot capable broadcast device. Without that + * notification the systems stays stuck in periodic mode + * forever. + */ + if (dev->features & CLOCK_EVT_FEAT_ONESHOT) + tick_clock_notify(); return 1; } @@ -124,7 +133,7 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) if (!tick_device_is_functional(dev)) { dev->event_handler = tick_handle_periodic; tick_device_setup_broadcast_func(dev); - cpumask_set_cpu(cpu, tick_get_broadcast_mask()); + cpumask_set_cpu(cpu, tick_broadcast_mask); tick_broadcast_start_periodic(tick_broadcast_device.evtdev); ret = 1; } else { @@ -135,7 +144,7 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) */ if (!(dev->features & CLOCK_EVT_FEAT_C3STOP)) { int cpu = smp_processor_id(); - cpumask_clear_cpu(cpu, tick_get_broadcast_mask()); + cpumask_clear_cpu(cpu, tick_broadcast_mask); tick_broadcast_clear_oneshot(cpu); } else { tick_device_setup_broadcast_func(dev); @@ -199,9 +208,8 @@ static void tick_do_periodic_broadcast(void) { raw_spin_lock(&tick_broadcast_lock); - cpumask_and(to_cpumask(tmpmask), - cpu_online_mask, tick_get_broadcast_mask()); - tick_do_broadcast(to_cpumask(tmpmask)); + cpumask_and(tmpmask, cpu_online_mask, tick_broadcast_mask); + tick_do_broadcast(tmpmask); raw_spin_unlock(&tick_broadcast_lock); } @@ -264,13 +272,12 @@ static void tick_do_broadcast_on_off(unsigned long *reason) if (!tick_device_is_functional(dev)) goto out; - bc_stopped = cpumask_empty(tick_get_broadcast_mask()); + bc_stopped = cpumask_empty(tick_broadcast_mask); switch (*reason) { case CLOCK_EVT_NOTIFY_BROADCAST_ON: case CLOCK_EVT_NOTIFY_BROADCAST_FORCE: - if (!cpumask_test_cpu(cpu, tick_get_broadcast_mask())) { - cpumask_set_cpu(cpu, tick_get_broadcast_mask()); + if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_mask)) { if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) clockevents_shutdown(dev); @@ -280,8 +287,7 @@ static void tick_do_broadcast_on_off(unsigned long *reason) break; case CLOCK_EVT_NOTIFY_BROADCAST_OFF: if (!tick_broadcast_force && - cpumask_test_cpu(cpu, tick_get_broadcast_mask())) { - cpumask_clear_cpu(cpu, tick_get_broadcast_mask()); + cpumask_test_and_clear_cpu(cpu, tick_broadcast_mask)) { if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) tick_setup_periodic(dev, 0); @@ -289,7 +295,7 @@ static void tick_do_broadcast_on_off(unsigned long *reason) break; } - if (cpumask_empty(tick_get_broadcast_mask())) { + if (cpumask_empty(tick_broadcast_mask)) { if (!bc_stopped) clockevents_shutdown(bc); } else if (bc_stopped) { @@ -338,10 +344,10 @@ void tick_shutdown_broadcast(unsigned int *cpup) raw_spin_lock_irqsave(&tick_broadcast_lock, flags); bc = tick_broadcast_device.evtdev; - cpumask_clear_cpu(cpu, tick_get_broadcast_mask()); + cpumask_clear_cpu(cpu, tick_broadcast_mask); if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) { - if (bc && cpumask_empty(tick_get_broadcast_mask())) + if (bc && cpumask_empty(tick_broadcast_mask)) clockevents_shutdown(bc); } @@ -377,13 +383,13 @@ int tick_resume_broadcast(void) switch (tick_broadcast_device.mode) { case TICKDEV_MODE_PERIODIC: - if (!cpumask_empty(tick_get_broadcast_mask())) + if (!cpumask_empty(tick_broadcast_mask)) tick_broadcast_start_periodic(bc); broadcast = cpumask_test_cpu(smp_processor_id(), - tick_get_broadcast_mask()); + tick_broadcast_mask); break; case TICKDEV_MODE_ONESHOT: - if (!cpumask_empty(tick_get_broadcast_mask())) + if (!cpumask_empty(tick_broadcast_mask)) broadcast = tick_resume_broadcast_oneshot(bc); break; } @@ -396,25 +402,58 @@ int tick_resume_broadcast(void) #ifdef CONFIG_TICK_ONESHOT -/* FIXME: use cpumask_var_t. */ -static DECLARE_BITMAP(tick_broadcast_oneshot_mask, NR_CPUS); +static cpumask_var_t tick_broadcast_oneshot_mask; +static cpumask_var_t tick_broadcast_pending_mask; +static cpumask_var_t tick_broadcast_force_mask; /* * Exposed for debugging: see timer_list.c */ struct cpumask *tick_get_broadcast_oneshot_mask(void) { - return to_cpumask(tick_broadcast_oneshot_mask); + return tick_broadcast_oneshot_mask; } -static int tick_broadcast_set_event(ktime_t expires, int force) +/* + * Called before going idle with interrupts disabled. Checks whether a + * broadcast event from the other core is about to happen. We detected + * that in tick_broadcast_oneshot_control(). The callsite can use this + * to avoid a deep idle transition as we are about to get the + * broadcast IPI right away. + */ +int tick_check_broadcast_expired(void) { - struct clock_event_device *bc = tick_broadcast_device.evtdev; + return cpumask_test_cpu(smp_processor_id(), tick_broadcast_force_mask); +} + +/* + * Set broadcast interrupt affinity + */ +static void tick_broadcast_set_affinity(struct clock_event_device *bc, + const struct cpumask *cpumask) +{ + if (!(bc->features & CLOCK_EVT_FEAT_DYNIRQ)) + return; + + if (cpumask_equal(bc->cpumask, cpumask)) + return; + + bc->cpumask = cpumask; + irq_set_affinity(bc->irq, bc->cpumask); +} + +static int tick_broadcast_set_event(struct clock_event_device *bc, int cpu, + ktime_t expires, int force) +{ + int ret; if (bc->mode != CLOCK_EVT_MODE_ONESHOT) clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); - return clockevents_program_event(bc, expires, force); + ret = clockevents_program_event(bc, expires, force); + if (!ret) + tick_broadcast_set_affinity(bc, cpumask_of(cpu)); + return ret; } int tick_resume_broadcast_oneshot(struct clock_event_device *bc) @@ -429,7 +468,7 @@ int tick_resume_broadcast_oneshot(struct clock_event_device *bc) */ void tick_check_oneshot_broadcast(int cpu) { - if (cpumask_test_cpu(cpu, to_cpumask(tick_broadcast_oneshot_mask))) { + if (cpumask_test_cpu(cpu, tick_broadcast_oneshot_mask)) { struct tick_device *td = &per_cpu(tick_cpu_device, cpu); clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_ONESHOT); @@ -443,27 +482,39 @@ static void tick_handle_oneshot_broadcast(struct clock_event_device *dev) { struct tick_device *td; ktime_t now, next_event; - int cpu; + int cpu, next_cpu = 0; raw_spin_lock(&tick_broadcast_lock); again: dev->next_event.tv64 = KTIME_MAX; next_event.tv64 = KTIME_MAX; - cpumask_clear(to_cpumask(tmpmask)); + cpumask_clear(tmpmask); now = ktime_get(); /* Find all expired events */ - for_each_cpu(cpu, tick_get_broadcast_oneshot_mask()) { + for_each_cpu(cpu, tick_broadcast_oneshot_mask) { td = &per_cpu(tick_cpu_device, cpu); - if (td->evtdev->next_event.tv64 <= now.tv64) - cpumask_set_cpu(cpu, to_cpumask(tmpmask)); - else if (td->evtdev->next_event.tv64 < next_event.tv64) + if (td->evtdev->next_event.tv64 <= now.tv64) { + cpumask_set_cpu(cpu, tmpmask); + /* + * Mark the remote cpu in the pending mask, so + * it can avoid reprogramming the cpu local + * timer in tick_broadcast_oneshot_control(). + */ + cpumask_set_cpu(cpu, tick_broadcast_pending_mask); + } else if (td->evtdev->next_event.tv64 < next_event.tv64) { next_event.tv64 = td->evtdev->next_event.tv64; + next_cpu = cpu; + } } + /* Take care of enforced broadcast requests */ + cpumask_or(tmpmask, tmpmask, tick_broadcast_force_mask); + cpumask_clear(tick_broadcast_force_mask); + /* * Wakeup the cpus which have an expired event. */ - tick_do_broadcast(to_cpumask(tmpmask)); + tick_do_broadcast(tmpmask); /* * Two reasons for reprogram: @@ -480,7 +531,7 @@ again: * Rearm the broadcast device. If event expired, * repeat the above */ - if (tick_broadcast_set_event(next_event, 0)) + if (tick_broadcast_set_event(dev, next_cpu, next_event, 0)) goto again; } raw_spin_unlock(&tick_broadcast_lock); @@ -495,6 +546,7 @@ void tick_broadcast_oneshot_control(unsigned long reason) struct clock_event_device *bc, *dev; struct tick_device *td; unsigned long flags; + ktime_t now; int cpu; /* @@ -519,21 +571,84 @@ void tick_broadcast_oneshot_control(unsigned long reason) raw_spin_lock_irqsave(&tick_broadcast_lock, flags); if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) { - if (!cpumask_test_cpu(cpu, tick_get_broadcast_oneshot_mask())) { - cpumask_set_cpu(cpu, tick_get_broadcast_oneshot_mask()); + WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask)); + if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_oneshot_mask)) { clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN); - if (dev->next_event.tv64 < bc->next_event.tv64) - tick_broadcast_set_event(dev->next_event, 1); + /* + * We only reprogram the broadcast timer if we + * did not mark ourself in the force mask and + * if the cpu local event is earlier than the + * broadcast event. If the current CPU is in + * the force mask, then we are going to be + * woken by the IPI right away. + */ + if (!cpumask_test_cpu(cpu, tick_broadcast_force_mask) && + dev->next_event.tv64 < bc->next_event.tv64) + tick_broadcast_set_event(bc, cpu, dev->next_event, 1); } } else { - if (cpumask_test_cpu(cpu, tick_get_broadcast_oneshot_mask())) { - cpumask_clear_cpu(cpu, - tick_get_broadcast_oneshot_mask()); + if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_oneshot_mask)) { clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT); - if (dev->next_event.tv64 != KTIME_MAX) - tick_program_event(dev->next_event, 1); + if (dev->next_event.tv64 == KTIME_MAX) + goto out; + /* + * The cpu which was handling the broadcast + * timer marked this cpu in the broadcast + * pending mask and fired the broadcast + * IPI. So we are going to handle the expired + * event anyway via the broadcast IPI + * handler. No need to reprogram the timer + * with an already expired event. + */ + if (cpumask_test_and_clear_cpu(cpu, + tick_broadcast_pending_mask)) + goto out; + + /* + * If the pending bit is not set, then we are + * either the CPU handling the broadcast + * interrupt or we got woken by something else. + * + * We are not longer in the broadcast mask, so + * if the cpu local expiry time is already + * reached, we would reprogram the cpu local + * timer with an already expired event. + * + * This can lead to a ping-pong when we return + * to idle and therefor rearm the broadcast + * timer before the cpu local timer was able + * to fire. This happens because the forced + * reprogramming makes sure that the event + * will happen in the future and depending on + * the min_delta setting this might be far + * enough out that the ping-pong starts. + * + * If the cpu local next_event has expired + * then we know that the broadcast timer + * next_event has expired as well and + * broadcast is about to be handled. So we + * avoid reprogramming and enforce that the + * broadcast handler, which did not run yet, + * will invoke the cpu local handler. + * + * We cannot call the handler directly from + * here, because we might be in a NOHZ phase + * and we did not go through the irq_enter() + * nohz fixups. + */ + now = ktime_get(); + if (dev->next_event.tv64 <= now.tv64) { + cpumask_set_cpu(cpu, tick_broadcast_force_mask); + goto out; + } + /* + * We got woken by something else. Reprogram + * the cpu local timer device. + */ + tick_program_event(dev->next_event, 1); } } +out: raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags); } @@ -544,7 +659,7 @@ void tick_broadcast_oneshot_control(unsigned long reason) */ static void tick_broadcast_clear_oneshot(int cpu) { - cpumask_clear_cpu(cpu, tick_get_broadcast_oneshot_mask()); + cpumask_clear_cpu(cpu, tick_broadcast_oneshot_mask); } static void tick_broadcast_init_next_event(struct cpumask *mask, @@ -582,17 +697,16 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc) * oneshot_mask bits for those and program the * broadcast device to fire. */ - cpumask_copy(to_cpumask(tmpmask), tick_get_broadcast_mask()); - cpumask_clear_cpu(cpu, to_cpumask(tmpmask)); - cpumask_or(tick_get_broadcast_oneshot_mask(), - tick_get_broadcast_oneshot_mask(), - to_cpumask(tmpmask)); + cpumask_copy(tmpmask, tick_broadcast_mask); + cpumask_clear_cpu(cpu, tmpmask); + cpumask_or(tick_broadcast_oneshot_mask, + tick_broadcast_oneshot_mask, tmpmask); - if (was_periodic && !cpumask_empty(to_cpumask(tmpmask))) { + if (was_periodic && !cpumask_empty(tmpmask)) { clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); - tick_broadcast_init_next_event(to_cpumask(tmpmask), + tick_broadcast_init_next_event(tmpmask, tick_next_period); - tick_broadcast_set_event(tick_next_period, 1); + tick_broadcast_set_event(bc, cpu, tick_next_period, 1); } else bc->next_event.tv64 = KTIME_MAX; } else { @@ -640,7 +754,7 @@ void tick_shutdown_broadcast_oneshot(unsigned int *cpup) * Clear the broadcast mask flag for the dead cpu, but do not * stop the broadcast device! */ - cpumask_clear_cpu(cpu, tick_get_broadcast_oneshot_mask()); + cpumask_clear_cpu(cpu, tick_broadcast_oneshot_mask); raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags); } @@ -664,3 +778,14 @@ bool tick_broadcast_oneshot_available(void) } #endif + +void __init tick_broadcast_init(void) +{ + alloc_cpumask_var(&tick_broadcast_mask, GFP_NOWAIT); + alloc_cpumask_var(&tmpmask, GFP_NOWAIT); +#ifdef CONFIG_TICK_ONESHOT + alloc_cpumask_var(&tick_broadcast_oneshot_mask, GFP_NOWAIT); + alloc_cpumask_var(&tick_broadcast_pending_mask, GFP_NOWAIT); + alloc_cpumask_var(&tick_broadcast_force_mask, GFP_NOWAIT); +#endif +} diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index b1600a6973f4..74413e396acc 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -416,4 +416,5 @@ static struct notifier_block tick_notifier = { void __init tick_init(void) { clockevents_register_notifier(&tick_notifier); + tick_broadcast_init(); } diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index cf3e59ed6dc0..f0299eae4602 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -4,6 +4,8 @@ #include <linux/hrtimer.h> #include <linux/tick.h> +extern seqlock_t jiffies_lock; + #ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD #define TICK_DO_TIMER_NONE -1 @@ -94,7 +96,7 @@ extern void tick_broadcast_on_off(unsigned long reason, int *oncpu); extern void tick_shutdown_broadcast(unsigned int *cpup); extern void tick_suspend_broadcast(void); extern int tick_resume_broadcast(void); - +extern void tick_broadcast_init(void); extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast); @@ -119,6 +121,7 @@ static inline void tick_broadcast_on_off(unsigned long reason, int *oncpu) { } static inline void tick_shutdown_broadcast(unsigned int *cpup) { } static inline void tick_suspend_broadcast(void) { } static inline int tick_resume_broadcast(void) { return 0; } +static inline void tick_broadcast_init(void) { } /* * Set the periodic handler in non broadcast mode diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index a19a39952c1b..225f8bf19095 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -482,8 +482,8 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) if (ratelimit < 10 && (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) { - printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n", - (unsigned int) local_softirq_pending()); + pr_warn("NOHZ: local_softirq_pending %02x\n", + (unsigned int) local_softirq_pending()); ratelimit++; } return false; diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 9a0bc98fbe1d..98cd470bbe49 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -23,8 +23,13 @@ #include <linux/stop_machine.h> #include <linux/pvclock_gtod.h> +#include "tick-internal.h" +#include "ntp_internal.h" static struct timekeeper timekeeper; +static DEFINE_RAW_SPINLOCK(timekeeper_lock); +static seqcount_t timekeeper_seq; +static struct timekeeper shadow_timekeeper; /* flag for if timekeeping is suspended */ int __read_mostly timekeeping_suspended; @@ -67,6 +72,7 @@ static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm) tk->wall_to_monotonic = wtm; set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec); tk->offs_real = timespec_to_ktime(tmp); + tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tk->tai_offset, 0)); } static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t) @@ -96,7 +102,7 @@ static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock) old_clock = tk->clock; tk->clock = clock; - clock->cycle_last = clock->read(clock); + tk->cycle_last = clock->cycle_last = clock->read(clock); /* Do the ns -> cycle conversion first, using original mult */ tmp = NTP_INTERVAL_LENGTH; @@ -201,8 +207,6 @@ static void update_pvclock_gtod(struct timekeeper *tk) /** * pvclock_gtod_register_notifier - register a pvclock timedata update listener - * - * Must hold write on timekeeper.lock */ int pvclock_gtod_register_notifier(struct notifier_block *nb) { @@ -210,11 +214,10 @@ int pvclock_gtod_register_notifier(struct notifier_block *nb) unsigned long flags; int ret; - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); ret = raw_notifier_chain_register(&pvclock_gtod_chain, nb); - /* update timekeeping data */ update_pvclock_gtod(tk); - write_sequnlock_irqrestore(&tk->lock, flags); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); return ret; } @@ -223,25 +226,22 @@ EXPORT_SYMBOL_GPL(pvclock_gtod_register_notifier); /** * pvclock_gtod_unregister_notifier - unregister a pvclock * timedata update listener - * - * Must hold write on timekeeper.lock */ int pvclock_gtod_unregister_notifier(struct notifier_block *nb) { - struct timekeeper *tk = &timekeeper; unsigned long flags; int ret; - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); ret = raw_notifier_chain_unregister(&pvclock_gtod_chain, nb); - write_sequnlock_irqrestore(&tk->lock, flags); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); return ret; } EXPORT_SYMBOL_GPL(pvclock_gtod_unregister_notifier); -/* must hold write on timekeeper.lock */ -static void timekeeping_update(struct timekeeper *tk, bool clearntp) +/* must hold timekeeper_lock */ +static void timekeeping_update(struct timekeeper *tk, bool clearntp, bool mirror) { if (clearntp) { tk->ntp_error = 0; @@ -249,6 +249,9 @@ static void timekeeping_update(struct timekeeper *tk, bool clearntp) } update_vsyscall(tk); update_pvclock_gtod(tk); + + if (mirror) + memcpy(&shadow_timekeeper, &timekeeper, sizeof(timekeeper)); } /** @@ -267,7 +270,7 @@ static void timekeeping_forward_now(struct timekeeper *tk) clock = tk->clock; cycle_now = clock->read(clock); cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - clock->cycle_last = cycle_now; + tk->cycle_last = clock->cycle_last = cycle_now; tk->xtime_nsec += cycle_delta * tk->mult; @@ -294,12 +297,12 @@ int __getnstimeofday(struct timespec *ts) s64 nsecs = 0; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); ts->tv_sec = tk->xtime_sec; nsecs = timekeeping_get_ns(tk); - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); ts->tv_nsec = 0; timespec_add_ns(ts, nsecs); @@ -335,11 +338,11 @@ ktime_t ktime_get(void) WARN_ON(timekeeping_suspended); do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); secs = tk->xtime_sec + tk->wall_to_monotonic.tv_sec; nsecs = timekeeping_get_ns(tk) + tk->wall_to_monotonic.tv_nsec; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); /* * Use ktime_set/ktime_add_ns to create a proper ktime on * 32-bit architectures without CONFIG_KTIME_SCALAR. @@ -366,12 +369,12 @@ void ktime_get_ts(struct timespec *ts) WARN_ON(timekeeping_suspended); do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); ts->tv_sec = tk->xtime_sec; nsec = timekeeping_get_ns(tk); tomono = tk->wall_to_monotonic; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); ts->tv_sec += tomono.tv_sec; ts->tv_nsec = 0; @@ -379,6 +382,50 @@ void ktime_get_ts(struct timespec *ts) } EXPORT_SYMBOL_GPL(ktime_get_ts); + +/** + * timekeeping_clocktai - Returns the TAI time of day in a timespec + * @ts: pointer to the timespec to be set + * + * Returns the time of day in a timespec. + */ +void timekeeping_clocktai(struct timespec *ts) +{ + struct timekeeper *tk = &timekeeper; + unsigned long seq; + u64 nsecs; + + WARN_ON(timekeeping_suspended); + + do { + seq = read_seqcount_begin(&timekeeper_seq); + + ts->tv_sec = tk->xtime_sec + tk->tai_offset; + nsecs = timekeeping_get_ns(tk); + + } while (read_seqcount_retry(&timekeeper_seq, seq)); + + ts->tv_nsec = 0; + timespec_add_ns(ts, nsecs); + +} +EXPORT_SYMBOL(timekeeping_clocktai); + + +/** + * ktime_get_clocktai - Returns the TAI time of day in a ktime + * + * Returns the time of day in a ktime. + */ +ktime_t ktime_get_clocktai(void) +{ + struct timespec ts; + + timekeeping_clocktai(&ts); + return timespec_to_ktime(ts); +} +EXPORT_SYMBOL(ktime_get_clocktai); + #ifdef CONFIG_NTP_PPS /** @@ -399,7 +446,7 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) WARN_ON_ONCE(timekeeping_suspended); do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); *ts_raw = tk->raw_time; ts_real->tv_sec = tk->xtime_sec; @@ -408,7 +455,7 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) nsecs_raw = timekeeping_get_ns_raw(tk); nsecs_real = timekeeping_get_ns(tk); - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); timespec_add_ns(ts_raw, nsecs_raw); timespec_add_ns(ts_real, nsecs_real); @@ -448,7 +495,8 @@ int do_settimeofday(const struct timespec *tv) if (!timespec_valid_strict(tv)) return -EINVAL; - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); timekeeping_forward_now(tk); @@ -460,9 +508,10 @@ int do_settimeofday(const struct timespec *tv) tk_set_xtime(tk, tv); - timekeeping_update(tk, true); + timekeeping_update(tk, true, true); - write_sequnlock_irqrestore(&tk->lock, flags); + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); /* signal hrtimers about time change */ clock_was_set(); @@ -487,7 +536,8 @@ int timekeeping_inject_offset(struct timespec *ts) if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) return -EINVAL; - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); timekeeping_forward_now(tk); @@ -502,9 +552,10 @@ int timekeeping_inject_offset(struct timespec *ts) tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *ts)); error: /* even if we error out, we forwarded the time, so call update */ - timekeeping_update(tk, true); + timekeeping_update(tk, true, true); - write_sequnlock_irqrestore(&tk->lock, flags); + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); /* signal hrtimers about time change */ clock_was_set(); @@ -513,6 +564,52 @@ error: /* even if we error out, we forwarded the time, so call update */ } EXPORT_SYMBOL(timekeeping_inject_offset); + +/** + * timekeeping_get_tai_offset - Returns current TAI offset from UTC + * + */ +s32 timekeeping_get_tai_offset(void) +{ + struct timekeeper *tk = &timekeeper; + unsigned int seq; + s32 ret; + + do { + seq = read_seqcount_begin(&timekeeper_seq); + ret = tk->tai_offset; + } while (read_seqcount_retry(&timekeeper_seq, seq)); + + return ret; +} + +/** + * __timekeeping_set_tai_offset - Lock free worker function + * + */ +static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset) +{ + tk->tai_offset = tai_offset; + tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tai_offset, 0)); +} + +/** + * timekeeping_set_tai_offset - Sets the current TAI offset from UTC + * + */ +void timekeeping_set_tai_offset(s32 tai_offset) +{ + struct timekeeper *tk = &timekeeper; + unsigned long flags; + + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); + __timekeeping_set_tai_offset(tk, tai_offset); + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); + clock_was_set(); +} + /** * change_clocksource - Swaps clocksources if a new one is available * @@ -526,7 +623,8 @@ static int change_clocksource(void *data) new = (struct clocksource *) data; - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); timekeeping_forward_now(tk); if (!new->enable || new->enable(new) == 0) { @@ -535,9 +633,10 @@ static int change_clocksource(void *data) if (old->disable) old->disable(old); } - timekeeping_update(tk, true); + timekeeping_update(tk, true, true); - write_sequnlock_irqrestore(&tk->lock, flags); + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); return 0; } @@ -587,11 +686,11 @@ void getrawmonotonic(struct timespec *ts) s64 nsecs; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); nsecs = timekeeping_get_ns_raw(tk); *ts = tk->raw_time; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); timespec_add_ns(ts, nsecs); } @@ -607,11 +706,11 @@ int timekeeping_valid_for_hres(void) int ret; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); ret = tk->clock->flags & CLOCK_SOURCE_VALID_FOR_HRES; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); return ret; } @@ -626,11 +725,11 @@ u64 timekeeping_max_deferment(void) u64 ret; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); ret = tk->clock->max_idle_ns; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); return ret; } @@ -693,11 +792,10 @@ void __init timekeeping_init(void) boot.tv_nsec = 0; } - seqlock_init(&tk->lock); - + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); ntp_init(); - write_seqlock_irqsave(&tk->lock, flags); clock = clocksource_default_clock(); if (clock->enable) clock->enable(clock); @@ -716,7 +814,10 @@ void __init timekeeping_init(void) tmp.tv_nsec = 0; tk_set_sleep_time(tk, tmp); - write_sequnlock_irqrestore(&tk->lock, flags); + memcpy(&shadow_timekeeper, &timekeeper, sizeof(timekeeper)); + + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); } /* time in seconds when suspend began */ @@ -764,15 +865,17 @@ void timekeeping_inject_sleeptime(struct timespec *delta) if (has_persistent_clock()) return; - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); timekeeping_forward_now(tk); __timekeeping_inject_sleeptime(tk, delta); - timekeeping_update(tk, true); + timekeeping_update(tk, true, true); - write_sequnlock_irqrestore(&tk->lock, flags); + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); /* signal hrtimers about time change */ clock_was_set(); @@ -788,26 +891,72 @@ void timekeeping_inject_sleeptime(struct timespec *delta) static void timekeeping_resume(void) { struct timekeeper *tk = &timekeeper; + struct clocksource *clock = tk->clock; unsigned long flags; - struct timespec ts; + struct timespec ts_new, ts_delta; + cycle_t cycle_now, cycle_delta; + bool suspendtime_found = false; - read_persistent_clock(&ts); + read_persistent_clock(&ts_new); clockevents_resume(); clocksource_resume(); - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); + + /* + * After system resumes, we need to calculate the suspended time and + * compensate it for the OS time. There are 3 sources that could be + * used: Nonstop clocksource during suspend, persistent clock and rtc + * device. + * + * One specific platform may have 1 or 2 or all of them, and the + * preference will be: + * suspend-nonstop clocksource -> persistent clock -> rtc + * The less preferred source will only be tried if there is no better + * usable source. The rtc part is handled separately in rtc core code. + */ + cycle_now = clock->read(clock); + if ((clock->flags & CLOCK_SOURCE_SUSPEND_NONSTOP) && + cycle_now > clock->cycle_last) { + u64 num, max = ULLONG_MAX; + u32 mult = clock->mult; + u32 shift = clock->shift; + s64 nsec = 0; + + cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { - ts = timespec_sub(ts, timekeeping_suspend_time); - __timekeeping_inject_sleeptime(tk, &ts); + /* + * "cycle_delta * mutl" may cause 64 bits overflow, if the + * suspended time is too long. In that case we need do the + * 64 bits math carefully + */ + do_div(max, mult); + if (cycle_delta > max) { + num = div64_u64(cycle_delta, max); + nsec = (((u64) max * mult) >> shift) * num; + cycle_delta -= num * max; + } + nsec += ((u64) cycle_delta * mult) >> shift; + + ts_delta = ns_to_timespec(nsec); + suspendtime_found = true; + } else if (timespec_compare(&ts_new, &timekeeping_suspend_time) > 0) { + ts_delta = timespec_sub(ts_new, timekeeping_suspend_time); + suspendtime_found = true; } - /* re-base the last cycle value */ - tk->clock->cycle_last = tk->clock->read(tk->clock); + + if (suspendtime_found) + __timekeeping_inject_sleeptime(tk, &ts_delta); + + /* Re-base the last cycle value */ + tk->cycle_last = clock->cycle_last = cycle_now; tk->ntp_error = 0; timekeeping_suspended = 0; - timekeeping_update(tk, false); - write_sequnlock_irqrestore(&tk->lock, flags); + timekeeping_update(tk, false, true); + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); touch_softlockup_watchdog(); @@ -826,7 +975,8 @@ static int timekeeping_suspend(void) read_persistent_clock(&timekeeping_suspend_time); - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); timekeeping_forward_now(tk); timekeeping_suspended = 1; @@ -849,7 +999,8 @@ static int timekeeping_suspend(void) timekeeping_suspend_time = timespec_add(timekeeping_suspend_time, delta_delta); } - write_sequnlock_irqrestore(&tk->lock, flags); + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL); clocksource_suspend(); @@ -1099,6 +1250,8 @@ static inline void accumulate_nsecs_to_secs(struct timekeeper *tk) tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, ts)); + __timekeeping_set_tai_offset(tk, tk->tai_offset - leap); + clock_was_set_delayed(); } } @@ -1116,15 +1269,16 @@ static inline void accumulate_nsecs_to_secs(struct timekeeper *tk) static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, u32 shift) { + cycle_t interval = tk->cycle_interval << shift; u64 raw_nsecs; /* If the offset is smaller then a shifted interval, do nothing */ - if (offset < tk->cycle_interval<<shift) + if (offset < interval) return offset; /* Accumulate one shifted interval */ - offset -= tk->cycle_interval << shift; - tk->clock->cycle_last += tk->cycle_interval << shift; + offset -= interval; + tk->cycle_last += interval; tk->xtime_nsec += tk->xtime_interval << shift; accumulate_nsecs_to_secs(tk); @@ -1181,27 +1335,28 @@ static inline void old_vsyscall_fixup(struct timekeeper *tk) static void update_wall_time(void) { struct clocksource *clock; - struct timekeeper *tk = &timekeeper; + struct timekeeper *real_tk = &timekeeper; + struct timekeeper *tk = &shadow_timekeeper; cycle_t offset; int shift = 0, maxshift; unsigned long flags; - write_seqlock_irqsave(&tk->lock, flags); + raw_spin_lock_irqsave(&timekeeper_lock, flags); /* Make sure we're fully resumed: */ if (unlikely(timekeeping_suspended)) goto out; - clock = tk->clock; + clock = real_tk->clock; #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET - offset = tk->cycle_interval; + offset = real_tk->cycle_interval; #else offset = (clock->read(clock) - clock->cycle_last) & clock->mask; #endif /* Check if there's really nothing to do */ - if (offset < tk->cycle_interval) + if (offset < real_tk->cycle_interval) goto out; /* @@ -1238,11 +1393,24 @@ static void update_wall_time(void) */ accumulate_nsecs_to_secs(tk); - timekeeping_update(tk, false); - + write_seqcount_begin(&timekeeper_seq); + /* Update clock->cycle_last with the new value */ + clock->cycle_last = tk->cycle_last; + /* + * Update the real timekeeper. + * + * We could avoid this memcpy by switching pointers, but that + * requires changes to all other timekeeper usage sites as + * well, i.e. move the timekeeper pointer getter into the + * spinlocked/seqcount protected sections. And we trade this + * memcpy under the timekeeper_seq against one before we start + * updating. + */ + memcpy(real_tk, tk, sizeof(*tk)); + timekeeping_update(real_tk, false, false); + write_seqcount_end(&timekeeper_seq); out: - write_sequnlock_irqrestore(&tk->lock, flags); - + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); } /** @@ -1289,13 +1457,13 @@ void get_monotonic_boottime(struct timespec *ts) WARN_ON(timekeeping_suspended); do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); ts->tv_sec = tk->xtime_sec; nsec = timekeeping_get_ns(tk); tomono = tk->wall_to_monotonic; sleep = tk->total_sleep_time; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); ts->tv_sec += tomono.tv_sec + sleep.tv_sec; ts->tv_nsec = 0; @@ -1354,10 +1522,10 @@ struct timespec current_kernel_time(void) unsigned long seq; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); now = tk_xtime(tk); - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); return now; } @@ -1370,11 +1538,11 @@ struct timespec get_monotonic_coarse(void) unsigned long seq; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); now = tk_xtime(tk); mono = tk->wall_to_monotonic; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); set_normalized_timespec(&now, now.tv_sec + mono.tv_sec, now.tv_nsec + mono.tv_nsec); @@ -1405,11 +1573,11 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, unsigned long seq; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); *xtim = tk_xtime(tk); *wtom = tk->wall_to_monotonic; *sleep = tk->total_sleep_time; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); } #ifdef CONFIG_HIGH_RES_TIMERS @@ -1421,7 +1589,8 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, * Returns current monotonic time and updates the offsets * Called from hrtimer_interupt() or retrigger_next_event() */ -ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot) +ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot, + ktime_t *offs_tai) { struct timekeeper *tk = &timekeeper; ktime_t now; @@ -1429,14 +1598,15 @@ ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot) u64 secs, nsecs; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); secs = tk->xtime_sec; nsecs = timekeeping_get_ns(tk); *offs_real = tk->offs_real; *offs_boot = tk->offs_boot; - } while (read_seqretry(&tk->lock, seq)); + *offs_tai = tk->offs_tai; + } while (read_seqcount_retry(&timekeeper_seq, seq)); now = ktime_add_ns(ktime_set(secs, 0), nsecs); now = ktime_sub(now, *offs_real); @@ -1454,15 +1624,79 @@ ktime_t ktime_get_monotonic_offset(void) struct timespec wtom; do { - seq = read_seqbegin(&tk->lock); + seq = read_seqcount_begin(&timekeeper_seq); wtom = tk->wall_to_monotonic; - } while (read_seqretry(&tk->lock, seq)); + } while (read_seqcount_retry(&timekeeper_seq, seq)); return timespec_to_ktime(wtom); } EXPORT_SYMBOL_GPL(ktime_get_monotonic_offset); /** + * do_adjtimex() - Accessor function to NTP __do_adjtimex function + */ +int do_adjtimex(struct timex *txc) +{ + struct timekeeper *tk = &timekeeper; + unsigned long flags; + struct timespec ts; + s32 orig_tai, tai; + int ret; + + /* Validate the data before disabling interrupts */ + ret = ntp_validate_timex(txc); + if (ret) + return ret; + + if (txc->modes & ADJ_SETOFFSET) { + struct timespec delta; + delta.tv_sec = txc->time.tv_sec; + delta.tv_nsec = txc->time.tv_usec; + if (!(txc->modes & ADJ_NANO)) + delta.tv_nsec *= 1000; + ret = timekeeping_inject_offset(&delta); + if (ret) + return ret; + } + + getnstimeofday(&ts); + + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); + + orig_tai = tai = tk->tai_offset; + ret = __do_adjtimex(txc, &ts, &tai); + + if (tai != orig_tai) { + __timekeeping_set_tai_offset(tk, tai); + clock_was_set_delayed(); + } + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); + + return ret; +} + +#ifdef CONFIG_NTP_PPS +/** + * hardpps() - Accessor function to NTP __hardpps function + */ +void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&timekeeper_lock, flags); + write_seqcount_begin(&timekeeper_seq); + + __hardpps(phase_ts, raw_ts); + + write_seqcount_end(&timekeeper_seq); + raw_spin_unlock_irqrestore(&timekeeper_lock, flags); +} +EXPORT_SYMBOL(hardpps); +#endif + +/** * xtime_update() - advances the timekeeping infrastructure * @ticks: number of ticks, that have elapsed since the last call. * diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c index af5a7e9f164b..3bdf28323012 100644 --- a/kernel/time/timer_list.c +++ b/kernel/time/timer_list.c @@ -20,6 +20,13 @@ #include <asm/uaccess.h> + +struct timer_list_iter { + int cpu; + bool second_pass; + u64 now; +}; + typedef void (*print_fn_t)(struct seq_file *m, unsigned int *classes); DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases); @@ -133,7 +140,6 @@ static void print_cpu(struct seq_file *m, int cpu, u64 now) struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu); int i; - SEQ_printf(m, "\n"); SEQ_printf(m, "cpu: %d\n", cpu); for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { SEQ_printf(m, " clock %d:\n", i); @@ -187,6 +193,7 @@ static void print_cpu(struct seq_file *m, int cpu, u64 now) #undef P #undef P_ns + SEQ_printf(m, "\n"); } #ifdef CONFIG_GENERIC_CLOCKEVENTS @@ -195,7 +202,6 @@ print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu) { struct clock_event_device *dev = td->evtdev; - SEQ_printf(m, "\n"); SEQ_printf(m, "Tick Device: mode: %d\n", td->mode); if (cpu < 0) SEQ_printf(m, "Broadcast device\n"); @@ -230,12 +236,11 @@ print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu) print_name_offset(m, dev->event_handler); SEQ_printf(m, "\n"); SEQ_printf(m, " retries: %lu\n", dev->retries); + SEQ_printf(m, "\n"); } -static void timer_list_show_tickdevices(struct seq_file *m) +static void timer_list_show_tickdevices_header(struct seq_file *m) { - int cpu; - #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST print_tickdevice(m, tick_get_broadcast_device(), -1); SEQ_printf(m, "tick_broadcast_mask: %08lx\n", @@ -246,47 +251,104 @@ static void timer_list_show_tickdevices(struct seq_file *m) #endif SEQ_printf(m, "\n"); #endif - for_each_online_cpu(cpu) - print_tickdevice(m, tick_get_device(cpu), cpu); - SEQ_printf(m, "\n"); } -#else -static void timer_list_show_tickdevices(struct seq_file *m) { } #endif +static inline void timer_list_header(struct seq_file *m, u64 now) +{ + SEQ_printf(m, "Timer List Version: v0.7\n"); + SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES); + SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now); + SEQ_printf(m, "\n"); +} + static int timer_list_show(struct seq_file *m, void *v) { + struct timer_list_iter *iter = v; + u64 now = ktime_to_ns(ktime_get()); + + if (iter->cpu == -1 && !iter->second_pass) + timer_list_header(m, now); + else if (!iter->second_pass) + print_cpu(m, iter->cpu, iter->now); +#ifdef CONFIG_GENERIC_CLOCKEVENTS + else if (iter->cpu == -1 && iter->second_pass) + timer_list_show_tickdevices_header(m); + else + print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu); +#endif + return 0; +} + +void sysrq_timer_list_show(void) +{ u64 now = ktime_to_ns(ktime_get()); int cpu; - SEQ_printf(m, "Timer List Version: v0.7\n"); - SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES); - SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now); + timer_list_header(NULL, now); for_each_online_cpu(cpu) - print_cpu(m, cpu, now); + print_cpu(NULL, cpu, now); - SEQ_printf(m, "\n"); - timer_list_show_tickdevices(m); +#ifdef CONFIG_GENERIC_CLOCKEVENTS + timer_list_show_tickdevices_header(NULL); + for_each_online_cpu(cpu) + print_tickdevice(NULL, tick_get_device(cpu), cpu); +#endif + return; +} - return 0; +static void *timer_list_start(struct seq_file *file, loff_t *offset) +{ + struct timer_list_iter *iter = file->private; + + if (!*offset) { + iter->cpu = -1; + iter->now = ktime_to_ns(ktime_get()); + } else if (iter->cpu >= nr_cpu_ids) { +#ifdef CONFIG_GENERIC_CLOCKEVENTS + if (!iter->second_pass) { + iter->cpu = -1; + iter->second_pass = true; + } else + return NULL; +#else + return NULL; +#endif + } + return iter; } -void sysrq_timer_list_show(void) +static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset) +{ + struct timer_list_iter *iter = file->private; + iter->cpu = cpumask_next(iter->cpu, cpu_online_mask); + ++*offset; + return timer_list_start(file, offset); +} + +static void timer_list_stop(struct seq_file *seq, void *v) { - timer_list_show(NULL, NULL); } +static const struct seq_operations timer_list_sops = { + .start = timer_list_start, + .next = timer_list_next, + .stop = timer_list_stop, + .show = timer_list_show, +}; + static int timer_list_open(struct inode *inode, struct file *filp) { - return single_open(filp, timer_list_show, NULL); + return seq_open_private(filp, &timer_list_sops, + sizeof(struct timer_list_iter)); } static const struct file_operations timer_list_fops = { .open = timer_list_open, .read = seq_read, .llseek = seq_lseek, - .release = single_release, + .release = seq_release_private, }; static int __init init_timer_list_procfs(void) |