diff options
Diffstat (limited to 'kernel/time')
| -rw-r--r-- | kernel/time/Kconfig | 58 | ||||
| -rw-r--r-- | kernel/time/alarmtimer.c | 4 | ||||
| -rw-r--r-- | kernel/time/clockevents.c | 3 | ||||
| -rw-r--r-- | kernel/time/ntp.c | 8 | ||||
| -rw-r--r-- | kernel/time/tick-broadcast.c | 13 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 26 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 6 |
7 files changed, 91 insertions, 27 deletions
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index a20dc8a3c94..fd42bd452b7 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -2,6 +2,55 @@ # Timer subsystem related configuration options # +# Options selectable by arch Kconfig + +# Watchdog function for clocksources to detect instabilities +config CLOCKSOURCE_WATCHDOG + bool + +# Architecture has extra clocksource data +config ARCH_CLOCKSOURCE_DATA + bool + +# Timekeeping vsyscall support +config GENERIC_TIME_VSYSCALL + bool + +# ktime_t scalar 64bit nsec representation +config KTIME_SCALAR + bool + +# Old style timekeeping +config ARCH_USES_GETTIMEOFFSET + bool + +# The generic clock events infrastructure +config GENERIC_CLOCKEVENTS + bool + +# Migration helper. Builds, but does not invoke +config GENERIC_CLOCKEVENTS_BUILD + bool + default y + depends on GENERIC_CLOCKEVENTS + +# Clockevents broadcasting infrastructure +config GENERIC_CLOCKEVENTS_BROADCAST + bool + depends on GENERIC_CLOCKEVENTS + +# Automatically adjust the min. reprogramming time for +# clock event device +config GENERIC_CLOCKEVENTS_MIN_ADJUST + bool + +# Generic update of CMOS clock +config GENERIC_CMOS_UPDATE + bool + +if GENERIC_CLOCKEVENTS +menu "Timers subsystem" + # Core internal switch. Selected by NO_HZ / HIGH_RES_TIMERS. This is # only related to the tick functionality. Oneshot clockevent devices # are supported independ of this. @@ -26,10 +75,5 @@ config HIGH_RES_TIMERS hardware is not capable then this option only increases the size of the kernel image. -config GENERIC_CLOCKEVENTS_BUILD - bool - default y - depends on GENERIC_CLOCKEVENTS - -config GENERIC_CLOCKEVENTS_MIN_ADJUST - bool +endmenu +endif diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 8a538c55fc7..aa27d391bfc 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -59,7 +59,7 @@ static DEFINE_SPINLOCK(rtcdev_lock); * If one has not already been chosen, it checks to see if a * functional rtc device is available. */ -static struct rtc_device *alarmtimer_get_rtcdev(void) +struct rtc_device *alarmtimer_get_rtcdev(void) { unsigned long flags; struct rtc_device *ret; @@ -115,7 +115,7 @@ static void alarmtimer_rtc_interface_remove(void) class_interface_unregister(&alarmtimer_rtc_interface); } #else -static inline struct rtc_device *alarmtimer_get_rtcdev(void) +struct rtc_device *alarmtimer_get_rtcdev(void) { return NULL; } diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 9cd928f7a7c..7e1ce012a85 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -297,8 +297,7 @@ void clockevents_register_device(struct clock_event_device *dev) } EXPORT_SYMBOL_GPL(clockevents_register_device); -static void clockevents_config(struct clock_event_device *dev, - u32 freq) +void clockevents_config(struct clock_event_device *dev, u32 freq) { u64 sec; diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index f03fd83b170..70b33abcc7b 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -412,6 +412,7 @@ int second_overflow(unsigned long secs) if (secs % 86400 == 0) { leap = -1; time_state = TIME_OOP; + time_tai++; printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n"); } @@ -426,7 +427,6 @@ int second_overflow(unsigned long secs) } break; case TIME_OOP: - time_tai++; time_state = TIME_WAIT; break; @@ -473,8 +473,6 @@ int second_overflow(unsigned long secs) << NTP_SCALE_SHIFT; time_adjust = 0; - - out: spin_unlock_irqrestore(&ntp_lock, flags); @@ -559,10 +557,10 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts) /* only set allowed bits */ time_status &= STA_RONLY; time_status |= txc->status & ~STA_RONLY; - } + /* - * Called with the xtime lock held, so we can access and modify + * 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) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index bf57abdc7bd..f113755695e 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -346,7 +346,8 @@ int tick_resume_broadcast(void) tick_get_broadcast_mask()); break; case TICKDEV_MODE_ONESHOT: - broadcast = tick_resume_broadcast_oneshot(bc); + if (!cpumask_empty(tick_get_broadcast_mask())) + broadcast = tick_resume_broadcast_oneshot(bc); break; } } @@ -373,6 +374,9 @@ static int tick_broadcast_set_event(ktime_t expires, int force) { struct clock_event_device *bc = tick_broadcast_device.evtdev; + if (bc->mode != CLOCK_EVT_MODE_ONESHOT) + clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); + return clockevents_program_event(bc, expires, force); } @@ -531,7 +535,6 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc) int was_periodic = bc->mode == CLOCK_EVT_MODE_PERIODIC; bc->event_handler = tick_handle_oneshot_broadcast; - clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); /* Take the do_timer update */ tick_do_timer_cpu = cpu; @@ -549,6 +552,7 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc) to_cpumask(tmpmask)); if (was_periodic && !cpumask_empty(to_cpumask(tmpmask))) { + clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); tick_broadcast_init_next_event(to_cpumask(tmpmask), tick_next_period); tick_broadcast_set_event(tick_next_period, 1); @@ -577,15 +581,10 @@ void tick_broadcast_switch_to_oneshot(void) raw_spin_lock_irqsave(&tick_broadcast_lock, flags); tick_broadcast_device.mode = TICKDEV_MODE_ONESHOT; - - if (cpumask_empty(tick_get_broadcast_mask())) - goto end; - bc = tick_broadcast_device.evtdev; if (bc) tick_broadcast_setup_oneshot(bc); -end: raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags); } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 6a3a5b9ff56..86999783392 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -274,6 +274,7 @@ EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us); static void tick_nohz_stop_sched_tick(struct tick_sched *ts) { unsigned long seq, last_jiffies, next_jiffies, delta_jiffies; + unsigned long rcu_delta_jiffies; ktime_t last_update, expires, now; struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; u64 time_delta; @@ -322,7 +323,7 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts) time_delta = timekeeping_max_deferment(); } while (read_seqretry(&xtime_lock, seq)); - if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu) || + if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) || printk_needs_cpu(cpu) || arch_needs_cpu(cpu)) { next_jiffies = last_jiffies + 1; delta_jiffies = 1; @@ -330,6 +331,10 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts) /* Get the next timer wheel timer */ next_jiffies = get_next_timer_interrupt(last_jiffies); delta_jiffies = next_jiffies - last_jiffies; + if (rcu_delta_jiffies < delta_jiffies) { + next_jiffies = last_jiffies + rcu_delta_jiffies; + delta_jiffies = rcu_delta_jiffies; + } } /* * Do not stop the tick, if we are only one off @@ -576,6 +581,7 @@ void tick_nohz_idle_exit(void) /* Update jiffies first */ select_nohz_load_balancer(0); tick_do_update_jiffies64(now); + update_cpu_load_nohz(); #ifndef CONFIG_VIRT_CPU_ACCOUNTING /* @@ -814,6 +820,16 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) return HRTIMER_RESTART; } +static int sched_skew_tick; + +static int __init skew_tick(char *str) +{ + get_option(&str, &sched_skew_tick); + + return 0; +} +early_param("skew_tick", skew_tick); + /** * tick_setup_sched_timer - setup the tick emulation timer */ @@ -831,6 +847,14 @@ void tick_setup_sched_timer(void) /* Get the next period (per cpu) */ hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update()); + /* Offset the tick to avert xtime_lock contention. */ + if (sched_skew_tick) { + u64 offset = ktime_to_ns(tick_period) >> 1; + do_div(offset, num_possible_cpus()); + offset *= smp_processor_id(); + hrtimer_add_expires_ns(&ts->sched_timer, offset); + } + for (;;) { hrtimer_forward(&ts->sched_timer, now, tick_period); hrtimer_start_expires(&ts->sched_timer, diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index d66b21308f7..6f46a00a1e8 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -240,7 +240,6 @@ void getnstimeofday(struct timespec *ts) timespec_add_ns(ts, nsecs); } - EXPORT_SYMBOL(getnstimeofday); ktime_t ktime_get(void) @@ -357,8 +356,8 @@ void do_gettimeofday(struct timeval *tv) tv->tv_sec = now.tv_sec; tv->tv_usec = now.tv_nsec/1000; } - EXPORT_SYMBOL(do_gettimeofday); + /** * do_settimeofday - Sets the time of day * @tv: pointer to the timespec variable containing the new time @@ -392,7 +391,6 @@ int do_settimeofday(const struct timespec *tv) return 0; } - EXPORT_SYMBOL(do_settimeofday); @@ -964,6 +962,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift) timekeeper.xtime.tv_sec++; leap = second_overflow(timekeeper.xtime.tv_sec); timekeeper.xtime.tv_sec += leap; + timekeeper.wall_to_monotonic.tv_sec -= leap; } /* Accumulate raw time */ @@ -1079,6 +1078,7 @@ static void update_wall_time(void) timekeeper.xtime.tv_sec++; leap = second_overflow(timekeeper.xtime.tv_sec); timekeeper.xtime.tv_sec += leap; + timekeeper.wall_to_monotonic.tv_sec -= leap; } timekeeping_update(false); |