diff options
Diffstat (limited to 'kernel/time')
-rw-r--r-- | kernel/time/Kconfig | 1 | ||||
-rw-r--r-- | kernel/time/clockevents.c | 12 | ||||
-rw-r--r-- | kernel/time/clocksource.c | 3 | ||||
-rw-r--r-- | kernel/time/jiffies.c | 1 | ||||
-rw-r--r-- | kernel/time/ntp.c | 96 | ||||
-rw-r--r-- | kernel/time/tick-broadcast.c | 36 | ||||
-rw-r--r-- | kernel/time/tick-common.c | 14 | ||||
-rw-r--r-- | kernel/time/tick-internal.h | 11 | ||||
-rw-r--r-- | kernel/time/tick-sched.c | 144 | ||||
-rw-r--r-- | kernel/time/timekeeping.c | 122 | ||||
-rw-r--r-- | kernel/time/timer_list.c | 28 |
11 files changed, 313 insertions, 155 deletions
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index 8d53106a0a92..95ed42951e0a 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -3,7 +3,6 @@ # config TICK_ONESHOT bool - default n config NO_HZ bool "Tickless System (Dynamic Ticks)" diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 1876b526c778..f8d968063cea 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -72,6 +72,16 @@ void clockevents_set_mode(struct clock_event_device *dev, } /** + * clockevents_shutdown - shutdown the device and clear next_event + * @dev: device to shutdown + */ +void clockevents_shutdown(struct clock_event_device *dev) +{ + clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN); + dev->next_event.tv64 = KTIME_MAX; +} + +/** * clockevents_program_event - Reprogram the clock event device. * @expires: absolute expiry time (monotonic clock) * @@ -206,7 +216,7 @@ void clockevents_exchange_device(struct clock_event_device *old, if (new) { BUG_ON(new->mode != CLOCK_EVT_MODE_UNUSED); - clockevents_set_mode(new, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(new); } local_irq_restore(flags); } diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 093d4acf993b..9ed2eec97526 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -325,6 +325,9 @@ int clocksource_register(struct clocksource *c) unsigned long flags; int ret; + /* save mult_orig on registration */ + c->mult_orig = c->mult; + spin_lock_irqsave(&clocksource_lock, flags); ret = clocksource_enqueue(c); if (!ret) diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c index 4c256fdb8875..1ca99557e929 100644 --- a/kernel/time/jiffies.c +++ b/kernel/time/jiffies.c @@ -61,6 +61,7 @@ struct clocksource clocksource_jiffies = { .read = jiffies_read, .mask = 0xffffffff, /*32bits*/ .mult = NSEC_PER_JIFFY << JIFFIES_SHIFT, /* details above */ + .mult_orig = NSEC_PER_JIFFY << JIFFIES_SHIFT, .shift = JIFFIES_SHIFT, }; diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 1ad46f3df6e7..8ff15e5d486b 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -10,13 +10,13 @@ #include <linux/mm.h> #include <linux/time.h> -#include <linux/timer.h> #include <linux/timex.h> #include <linux/jiffies.h> #include <linux/hrtimer.h> #include <linux/capability.h> #include <linux/math64.h> #include <linux/clocksource.h> +#include <linux/workqueue.h> #include <asm/timex.h> /* @@ -142,8 +142,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) time_state = TIME_OOP; printk(KERN_NOTICE "Clock: " "inserting leap second 23:59:60 UTC\n"); - leap_timer.expires = ktime_add_ns(leap_timer.expires, - NSEC_PER_SEC); + hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC); res = HRTIMER_RESTART; break; case TIME_DEL: @@ -218,11 +217,11 @@ void second_overflow(void) /* Disable the cmos update - used by virtualization and embedded */ int no_sync_cmos_clock __read_mostly; -static void sync_cmos_clock(unsigned long dummy); +static void sync_cmos_clock(struct work_struct *work); -static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0); +static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock); -static void sync_cmos_clock(unsigned long dummy) +static void sync_cmos_clock(struct work_struct *work) { struct timespec now, next; int fail = 1; @@ -258,13 +257,13 @@ static void sync_cmos_clock(unsigned long dummy) next.tv_sec++; next.tv_nsec -= NSEC_PER_SEC; } - mod_timer(&sync_cmos_timer, jiffies + timespec_to_jiffies(&next)); + schedule_delayed_work(&sync_cmos_work, timespec_to_jiffies(&next)); } static void notify_cmos_timer(void) { if (!no_sync_cmos_clock) - mod_timer(&sync_cmos_timer, jiffies + 1); + schedule_delayed_work(&sync_cmos_work, 0); } #else @@ -277,38 +276,50 @@ static inline void notify_cmos_timer(void) { } int do_adjtimex(struct timex *txc) { struct timespec ts; - long save_adjust, sec; int result; - /* In order to modify anything, you gotta be super-user! */ - if (txc->modes && !capable(CAP_SYS_TIME)) - return -EPERM; - - /* Now we validate the data before disabling interrupts */ - - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) { + /* 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_SS_READ) + if (!(txc->modes & ADJ_OFFSET_SINGLESHOT)) return -EINVAL; + if (!(txc->modes & ADJ_OFFSET_READONLY) && + !capable(CAP_SYS_TIME)) + return -EPERM; + } else { + /* 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% something is VERY wrong! */ + if (txc->modes & ADJ_TICK && + (txc->tick < 900000/USER_HZ || + txc->tick > 1100000/USER_HZ)) + return -EINVAL; + + if (txc->modes & ADJ_STATUS && time_state != TIME_OK) + hrtimer_cancel(&leap_timer); } - /* if the quartz is off by more than 10% something is VERY wrong ! */ - if (txc->modes & ADJ_TICK) - if (txc->tick < 900000/USER_HZ || - txc->tick > 1100000/USER_HZ) - return -EINVAL; - - if (time_state != TIME_OK && txc->modes & ADJ_STATUS) - hrtimer_cancel(&leap_timer); getnstimeofday(&ts); write_seqlock_irq(&xtime_lock); - /* Save for later - semantics of adjtime is to return old value */ - save_adjust = time_adjust; - /* If there are input parameters, then process them */ + if (txc->modes & ADJ_ADJTIME) { + long save_adjust = time_adjust; + + if (!(txc->modes & ADJ_OFFSET_READONLY)) { + /* adjtime() is independent from ntp_adjtime() */ + time_adjust = txc->offset; + ntp_update_frequency(); + } + txc->offset = save_adjust; + goto adj_done; + } if (txc->modes) { + long sec; + if (txc->modes & ADJ_STATUS) { if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) { @@ -375,13 +386,8 @@ int do_adjtimex(struct timex *txc) if (txc->modes & ADJ_TAI && txc->constant > 0) time_tai = txc->constant; - if (txc->modes & ADJ_OFFSET) { - if (txc->modes == ADJ_OFFSET_SINGLESHOT) - /* adjtime() is independent from ntp_adjtime() */ - time_adjust = txc->offset; - else - ntp_update_offset(txc->offset); - } + if (txc->modes & ADJ_OFFSET) + ntp_update_offset(txc->offset); if (txc->modes & ADJ_TICK) tick_usec = txc->tick; @@ -389,22 +395,18 @@ int do_adjtimex(struct timex *txc) ntp_update_frequency(); } + txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, + NTP_SCALE_SHIFT); + if (!(time_status & STA_NANO)) + txc->offset /= NSEC_PER_USEC; + +adj_done: result = time_state; /* mostly `TIME_OK' */ if (time_status & (STA_UNSYNC|STA_CLOCKERR)) result = TIME_ERROR; - if ((txc->modes == ADJ_OFFSET_SINGLESHOT) || - (txc->modes == ADJ_OFFSET_SS_READ)) - txc->offset = save_adjust; - else { - txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, - NTP_SCALE_SHIFT); - if (!(time_status & STA_NANO)) - txc->offset /= NSEC_PER_USEC; - } - txc->freq = shift_right((s32)(time_freq >> PPM_SCALE_INV_SHIFT) * - (s64)PPM_SCALE_INV, - NTP_SCALE_SHIFT); + txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * + (s64)PPM_SCALE_INV, NTP_SCALE_SHIFT); txc->maxerror = time_maxerror; txc->esterror = time_esterror; txc->status = time_status; diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 2f5a38294bf9..f98a1b7b16e9 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -235,9 +235,9 @@ static void tick_do_broadcast_on_off(void *why) case CLOCK_EVT_NOTIFY_BROADCAST_FORCE: if (!cpu_isset(cpu, tick_broadcast_mask)) { cpu_set(cpu, tick_broadcast_mask); - if (td->mode == TICKDEV_MODE_PERIODIC) - clockevents_set_mode(dev, - CLOCK_EVT_MODE_SHUTDOWN); + if (tick_broadcast_device.mode == + TICKDEV_MODE_PERIODIC) + clockevents_shutdown(dev); } if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE) tick_broadcast_force = 1; @@ -246,7 +246,8 @@ static void tick_do_broadcast_on_off(void *why) if (!tick_broadcast_force && cpu_isset(cpu, tick_broadcast_mask)) { cpu_clear(cpu, tick_broadcast_mask); - if (td->mode == TICKDEV_MODE_PERIODIC) + if (tick_broadcast_device.mode == + TICKDEV_MODE_PERIODIC) tick_setup_periodic(dev, 0); } break; @@ -254,7 +255,7 @@ static void tick_do_broadcast_on_off(void *why) if (cpus_empty(tick_broadcast_mask)) { if (!bc_stopped) - clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(bc); } else if (bc_stopped) { if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) tick_broadcast_start_periodic(bc); @@ -306,7 +307,7 @@ void tick_shutdown_broadcast(unsigned int *cpup) if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) { if (bc && cpus_empty(tick_broadcast_mask)) - clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(bc); } spin_unlock_irqrestore(&tick_broadcast_lock, flags); @@ -321,7 +322,7 @@ void tick_suspend_broadcast(void) bc = tick_broadcast_device.evtdev; if (bc) - clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(bc); spin_unlock_irqrestore(&tick_broadcast_lock, flags); } @@ -383,6 +384,19 @@ int tick_resume_broadcast_oneshot(struct clock_event_device *bc) } /* + * Called from irq_enter() when idle was interrupted to reenable the + * per cpu device. + */ +void tick_check_oneshot_broadcast(int cpu) +{ + if (cpu_isset(cpu, tick_broadcast_oneshot_mask)) { + struct tick_device *td = &per_cpu(tick_cpu_device, cpu); + + clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_ONESHOT); + } +} + +/* * Handle oneshot mode broadcasting */ static void tick_handle_oneshot_broadcast(struct clock_event_device *dev) @@ -576,4 +590,12 @@ void tick_shutdown_broadcast_oneshot(unsigned int *cpup) spin_unlock_irqrestore(&tick_broadcast_lock, flags); } +/* + * Check, whether the broadcast device is in one shot mode + */ +int tick_broadcast_oneshot_active(void) +{ + return tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT; +} + #endif diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index c4777193d567..df12434b43ca 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -33,7 +33,7 @@ DEFINE_PER_CPU(struct tick_device, tick_cpu_device); */ ktime_t tick_next_period; ktime_t tick_period; -int tick_do_timer_cpu __read_mostly = -1; +int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT; DEFINE_SPINLOCK(tick_device_lock); /* @@ -109,7 +109,8 @@ void tick_setup_periodic(struct clock_event_device *dev, int broadcast) if (!tick_device_is_functional(dev)) return; - if (dev->features & CLOCK_EVT_FEAT_PERIODIC) { + if ((dev->features & CLOCK_EVT_FEAT_PERIODIC) && + !tick_broadcast_oneshot_active()) { clockevents_set_mode(dev, CLOCK_EVT_MODE_PERIODIC); } else { unsigned long seq; @@ -148,7 +149,7 @@ static void tick_setup_device(struct tick_device *td, * If no cpu took the do_timer update, assign it to * this cpu: */ - if (tick_do_timer_cpu == -1) { + if (tick_do_timer_cpu == TICK_DO_TIMER_BOOT) { tick_do_timer_cpu = cpu; tick_next_period = ktime_get(); tick_period = ktime_set(0, NSEC_PER_SEC / HZ); @@ -249,7 +250,7 @@ static int tick_check_new_device(struct clock_event_device *newdev) * not give it back to the clockevents layer ! */ if (tick_is_broadcast_device(curdev)) { - clockevents_set_mode(curdev, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(curdev); curdev = NULL; } clockevents_exchange_device(curdev, newdev); @@ -300,7 +301,8 @@ static void tick_shutdown(unsigned int *cpup) if (*cpup == tick_do_timer_cpu) { int cpu = first_cpu(cpu_online_map); - tick_do_timer_cpu = (cpu != NR_CPUS) ? cpu : -1; + tick_do_timer_cpu = (cpu != NR_CPUS) ? cpu : + TICK_DO_TIMER_NONE; } spin_unlock_irqrestore(&tick_device_lock, flags); } @@ -311,7 +313,7 @@ static void tick_suspend(void) unsigned long flags; spin_lock_irqsave(&tick_device_lock, flags); - clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(td->evtdev); spin_unlock_irqrestore(&tick_device_lock, flags); } diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 0ffc2918ea6f..b1c05bf75ee0 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -1,6 +1,10 @@ /* * tick internal variable and functions used by low/high res code */ + +#define TICK_DO_TIMER_NONE -1 +#define TICK_DO_TIMER_BOOT -2 + DECLARE_PER_CPU(struct tick_device, tick_cpu_device); extern spinlock_t tick_device_lock; extern ktime_t tick_next_period; @@ -10,6 +14,8 @@ extern int tick_do_timer_cpu __read_mostly; extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast); extern void tick_handle_periodic(struct clock_event_device *dev); +extern void clockevents_shutdown(struct clock_event_device *dev); + /* * NO_HZ / high resolution timer shared code */ @@ -29,6 +35,8 @@ extern void tick_broadcast_oneshot_control(unsigned long reason); extern void tick_broadcast_switch_to_oneshot(void); extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup); extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc); +extern int tick_broadcast_oneshot_active(void); +extern void tick_check_oneshot_broadcast(int cpu); # else /* BROADCAST */ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { @@ -37,6 +45,8 @@ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) static inline void tick_broadcast_oneshot_control(unsigned long reason) { } static inline void tick_broadcast_switch_to_oneshot(void) { } static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { } +static inline int tick_broadcast_oneshot_active(void) { return 0; } +static inline void tick_check_oneshot_broadcast(int cpu) { } # endif /* !BROADCAST */ #else /* !ONESHOT */ @@ -66,6 +76,7 @@ static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc) { return 0; } +static inline int tick_broadcast_oneshot_active(void) { return 0; } #endif /* !TICK_ONESHOT */ /* diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index a87b0468568b..342fc9ccab46 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -20,6 +20,7 @@ #include <linux/profile.h> #include <linux/sched.h> #include <linux/tick.h> +#include <linux/module.h> #include <asm/irq_regs.h> @@ -75,6 +76,9 @@ static void tick_do_update_jiffies64(ktime_t now) incr * ticks); } do_timer(++ticks); + + /* Keep the tick_next_period variable up to date */ + tick_next_period = ktime_add(last_jiffies_update, tick_period); } write_sequnlock(&xtime_lock); } @@ -151,7 +155,7 @@ void tick_nohz_update_jiffies(void) touch_softlockup_watchdog(); } -void tick_nohz_stop_idle(int cpu) +static void tick_nohz_stop_idle(int cpu) { struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); @@ -187,9 +191,17 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time) { struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); - *last_update_time = ktime_to_us(ts->idle_lastupdate); + if (!tick_nohz_enabled) + return -1; + + if (ts->idle_active) + *last_update_time = ktime_to_us(ts->idle_lastupdate); + else + *last_update_time = ktime_to_us(ktime_get()); + return ktime_to_us(ts->idle_sleeptime); } +EXPORT_SYMBOL_GPL(get_cpu_idle_time_us); /** * tick_nohz_stop_sched_tick - stop the idle tick from the idle task @@ -221,7 +233,7 @@ void tick_nohz_stop_sched_tick(int inidle) */ if (unlikely(!cpu_online(cpu))) { if (cpu == tick_do_timer_cpu) - tick_do_timer_cpu = -1; + tick_do_timer_cpu = TICK_DO_TIMER_NONE; } if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE)) @@ -258,7 +270,7 @@ void tick_nohz_stop_sched_tick(int inidle) next_jiffies = get_next_timer_interrupt(last_jiffies); delta_jiffies = next_jiffies - last_jiffies; - if (rcu_needs_cpu(cpu)) + if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu)) delta_jiffies = 1; /* * Do not stop the tick, if we are only one off @@ -288,7 +300,7 @@ void tick_nohz_stop_sched_tick(int inidle) goto out; } - ts->idle_tick = ts->sched_timer.expires; + ts->idle_tick = hrtimer_get_expires(&ts->sched_timer); ts->tick_stopped = 1; ts->idle_jiffies = last_jiffies; rcu_enter_nohz(); @@ -303,7 +315,7 @@ void tick_nohz_stop_sched_tick(int inidle) * invoked. */ if (cpu == tick_do_timer_cpu) - tick_do_timer_cpu = -1; + tick_do_timer_cpu = TICK_DO_TIMER_NONE; ts->idle_sleeps++; @@ -365,6 +377,32 @@ ktime_t tick_nohz_get_sleep_length(void) return ts->sleep_length; } +static void tick_nohz_restart(struct tick_sched *ts, ktime_t now) +{ + hrtimer_cancel(&ts->sched_timer); + hrtimer_set_expires(&ts->sched_timer, ts->idle_tick); + + while (1) { + /* Forward the time to expire in the future */ + hrtimer_forward(&ts->sched_timer, now, tick_period); + + if (ts->nohz_mode == NOHZ_MODE_HIGHRES) { + hrtimer_start_expires(&ts->sched_timer, + HRTIMER_MODE_ABS); + /* Check, if the timer was already in the past */ + if (hrtimer_active(&ts->sched_timer)) + break; + } else { + if (!tick_program_event( + hrtimer_get_expires(&ts->sched_timer), 0)) + break; + } + /* Update jiffies and reread time */ + tick_do_update_jiffies64(now); + now = ktime_get(); + } +} + /** * tick_nohz_restart_sched_tick - restart the idle tick from the idle task * @@ -418,35 +456,16 @@ void tick_nohz_restart_sched_tick(void) */ ts->tick_stopped = 0; ts->idle_exittime = now; - hrtimer_cancel(&ts->sched_timer); - ts->sched_timer.expires = ts->idle_tick; - while (1) { - /* Forward the time to expire in the future */ - hrtimer_forward(&ts->sched_timer, now, tick_period); + tick_nohz_restart(ts, now); - if (ts->nohz_mode == NOHZ_MODE_HIGHRES) { - hrtimer_start(&ts->sched_timer, - ts->sched_timer.expires, - HRTIMER_MODE_ABS); - /* Check, if the timer was already in the past */ - if (hrtimer_active(&ts->sched_timer)) - break; - } else { - if (!tick_program_event(ts->sched_timer.expires, 0)) - break; - } - /* Update jiffies and reread time */ - tick_do_update_jiffies64(now); - now = ktime_get(); - } local_irq_enable(); } static int tick_nohz_reprogram(struct tick_sched *ts, ktime_t now) { hrtimer_forward(&ts->sched_timer, now, tick_period); - return tick_program_event(ts->sched_timer.expires, 0); + return tick_program_event(hrtimer_get_expires(&ts->sched_timer), 0); } /* @@ -468,7 +487,7 @@ static void tick_nohz_handler(struct clock_event_device *dev) * this duty, then the jiffies update is still serialized by * xtime_lock. */ - if (unlikely(tick_do_timer_cpu == -1)) + if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE)) tick_do_timer_cpu = cpu; /* Check, if the jiffies need an update */ @@ -491,10 +510,6 @@ static void tick_nohz_handler(struct clock_event_device *dev) update_process_times(user_mode(regs)); profile_tick(CPU_PROFILING); - /* Do not restart, when we are in the idle loop */ - if (ts->tick_stopped) - return; - while (tick_nohz_reprogram(ts, now)) { now = ktime_get(); tick_do_update_jiffies64(now); @@ -529,7 +544,7 @@ static void tick_nohz_switch_to_nohz(void) next = tick_init_jiffy_update(); for (;;) { - ts->sched_timer.expires = next; + hrtimer_set_expires(&ts->sched_timer, next); if (!tick_program_event(next, 0)) break; next = ktime_add(next, tick_period); @@ -540,6 +555,41 @@ static void tick_nohz_switch_to_nohz(void) smp_processor_id()); } +/* + * When NOHZ is enabled and the tick is stopped, we need to kick the + * tick timer from irq_enter() so that the jiffies update is kept + * alive during long running softirqs. That's ugly as hell, but + * correctness is key even if we need to fix the offending softirq in + * the first place. + * + * Note, this is different to tick_nohz_restart. We just kick the + * timer and do not touch the other magic bits which need to be done + * when idle is left. + */ +static void tick_nohz_kick_tick(int cpu) +{ +#if 0 + /* Switch back to 2.6.27 behaviour */ + + struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + ktime_t delta, now; + + if (!ts->tick_stopped) + return; + + /* + * Do not touch the tick device, when the next expiry is either + * already reached or less/equal than the tick period. + */ + now = ktime_get(); + delta = ktime_sub(hrtimer_get_expires(&ts->sched_timer), now); + if (delta.tv64 <= tick_period.tv64) + return; + + tick_nohz_restart(ts, now); +#endif +} + #else static inline void tick_nohz_switch_to_nohz(void) { } @@ -547,6 +597,19 @@ static inline void tick_nohz_switch_to_nohz(void) { } #endif /* NO_HZ */ /* + * Called from irq_enter to notify about the possible interruption of idle() + */ +void tick_check_idle(int cpu) +{ + tick_check_oneshot_broadcast(cpu); +#ifdef CONFIG_NO_HZ + tick_nohz_stop_idle(cpu); + tick_nohz_update_jiffies(); + tick_nohz_kick_tick(cpu); +#endif +} + +/* * High resolution timer specific code */ #ifdef CONFIG_HIGH_RES_TIMERS @@ -570,7 +633,7 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) * this duty, then the jiffies update is still serialized by * xtime_lock. */ - if (unlikely(tick_do_timer_cpu == -1)) + if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE)) tick_do_timer_cpu = cpu; #endif @@ -599,10 +662,6 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) profile_tick(CPU_PROFILING); } - /* Do not restart, when we are in the idle loop */ - if (ts->tick_stopped) - return HRTIMER_NORESTART; - hrtimer_forward(timer, now, tick_period); return HRTIMER_RESTART; @@ -622,19 +681,18 @@ void tick_setup_sched_timer(void) */ hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); ts->sched_timer.function = tick_sched_timer; - ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; + ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU; /* Get the next period (per cpu) */ - ts->sched_timer.expires = tick_init_jiffy_update(); + hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update()); offset = ktime_to_ns(tick_period) >> 1; do_div(offset, num_possible_cpus()); offset *= smp_processor_id(); - ts->sched_timer.expires = ktime_add_ns(ts->sched_timer.expires, offset); + hrtimer_add_expires_ns(&ts->sched_timer, offset); for (;;) { hrtimer_forward(&ts->sched_timer, now, tick_period); - hrtimer_start(&ts->sched_timer, ts->sched_timer.expires, - HRTIMER_MODE_ABS); + hrtimer_start_expires(&ts->sched_timer, HRTIMER_MODE_ABS); /* Check, if the timer was already in the past */ if (hrtimer_active(&ts->sched_timer)) break; diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index e91c29f961c9..e7acfb482a68 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -58,27 +58,26 @@ struct clocksource *clock; #ifdef CONFIG_GENERIC_TIME /** - * __get_nsec_offset - Returns nanoseconds since last call to periodic_hook + * clocksource_forward_now - update clock to the current time * - * private function, must hold xtime_lock lock when being - * called. Returns the number of nanoseconds since the - * last call to update_wall_time() (adjusted by NTP scaling) + * Forward the current clock to update its state since the last call to + * update_wall_time(). This is useful before significant clock changes, + * as it avoids having to deal with this time offset explicitly. */ -static inline s64 __get_nsec_offset(void) +static void clocksource_forward_now(void) { cycle_t cycle_now, cycle_delta; - s64 ns_offset; + s64 nsec; - /* read clocksource: */ cycle_now = clocksource_read(clock); - - /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; + clock->cycle_last = cycle_now; - /* convert to nanoseconds: */ - ns_offset = cyc2ns(clock, cycle_delta); + nsec = cyc2ns(clock, cycle_delta); + timespec_add_ns(&xtime, nsec); - return ns_offset; + nsec = ((s64)cycle_delta * clock->mult_orig) >> clock->shift; + clock->raw_time.tv_nsec += nsec; } /** @@ -89,6 +88,7 @@ static inline s64 __get_nsec_offset(void) */ void getnstimeofday(struct timespec *ts) { + cycle_t cycle_now, cycle_delta; unsigned long seq; s64 nsecs; @@ -96,7 +96,15 @@ void getnstimeofday(struct timespec *ts) seq = read_seqbegin(&xtime_lock); *ts = xtime; - nsecs = __get_nsec_offset(); + + /* read clocksource: */ + cycle_now = clocksource_read(clock); + + /* calculate the delta since the last update_wall_time: */ + cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; + + /* convert to nanoseconds: */ + nsecs = cyc2ns(clock, cycle_delta); } while (read_seqretry(&xtime_lock, seq)); @@ -129,22 +137,22 @@ EXPORT_SYMBOL(do_gettimeofday); */ int do_settimeofday(struct timespec *tv) { + struct timespec ts_delta; unsigned long flags; - time_t wtm_sec, sec = tv->tv_sec; - long wtm_nsec, nsec = tv->tv_nsec; if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) return -EINVAL; write_seqlock_irqsave(&xtime_lock, flags); - nsec -= __get_nsec_offset(); + clocksource_forward_now(); + + ts_delta.tv_sec = tv->tv_sec - xtime.tv_sec; + ts_delta.tv_nsec = tv->tv_nsec - xtime.tv_nsec; + wall_to_monotonic = timespec_sub(wall_to_monotonic, ts_delta); - wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); - wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); + xtime = *tv; - set_normalized_timespec(&xtime, sec, nsec); - set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); update_xtime_cache(0); clock->error = 0; @@ -170,22 +178,19 @@ EXPORT_SYMBOL(do_settimeofday); static void change_clocksource(void) { struct clocksource *new; - cycle_t now; - u64 nsec; new = clocksource_get_next(); if (clock == new) return; - new->cycle_last = 0; - now = clocksource_read(new); - nsec = __get_nsec_offset(); - timespec_add_ns(&xtime, nsec); + clocksource_forward_now(); - clock = new; - clock->cycle_last = now; + new->raw_time = clock->raw_time; + clock = new; + clock->cycle_last = 0; + clock->cycle_last = clocksource_read(new); clock->error = 0; clock->xtime_nsec = 0; clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); @@ -200,11 +205,44 @@ static void change_clocksource(void) */ } #else +static inline void clocksource_forward_now(void) { } static inline void change_clocksource(void) { } -static inline s64 __get_nsec_offset(void) { return 0; } #endif /** + * getrawmonotonic - Returns the raw monotonic time in a timespec + * @ts: pointer to the timespec to be set + * + * Returns the raw monotonic time (completely un-modified by ntp) + */ +void getrawmonotonic(struct timespec *ts) +{ + unsigned long seq; + s64 nsecs; + cycle_t cycle_now, cycle_delta; + + do { + seq = read_seqbegin(&xtime_lock); + + /* read clocksource: */ + cycle_now = clocksource_read(clock); + + /* calculate the delta since the last update_wall_time: */ + cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; + + /* convert to nanoseconds: */ + nsecs = ((s64)cycle_delta * clock->mult_orig) >> clock->shift; + + *ts = clock->raw_time; + + } while (read_seqretry(&xtime_lock, seq)); + + timespec_add_ns(ts, nsecs); +} +EXPORT_SYMBOL(getrawmonotonic); + + +/** * timekeeping_valid_for_hres - Check if timekeeping is suitable for hres */ int timekeeping_valid_for_hres(void) @@ -265,8 +303,6 @@ void __init timekeeping_init(void) static int timekeeping_suspended; /* time in seconds when suspend began */ static unsigned long timekeeping_suspend_time; -/* xtime offset when we went into suspend */ -static s64 timekeeping_suspend_nsecs; /** * timekeeping_resume - Resumes the generic timekeeping subsystem. @@ -292,8 +328,6 @@ static int timekeeping_resume(struct sys_device *dev) wall_to_monotonic.tv_sec -= sleep_length; total_sleep_time += sleep_length; } - /* Make sure that we have the correct xtime reference */ - timespec_add_ns(&xtime, timekeeping_suspend_nsecs); update_xtime_cache(0); /* re-base the last cycle value */ clock->cycle_last = 0; @@ -319,8 +353,7 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state) timekeeping_suspend_time = read_persistent_clock(); write_seqlock_irqsave(&xtime_lock, flags); - /* Get the current xtime offset */ - timekeeping_suspend_nsecs = __get_nsec_offset(); + clocksource_forward_now(); timekeeping_suspended = 1; write_sequnlock_irqrestore(&xtime_lock, flags); @@ -454,23 +487,29 @@ void update_wall_time(void) #else offset = clock->cycle_interval; #endif - clock->xtime_nsec += (s64)xtime.tv_nsec << clock->shift; + clock->xtime_nsec = (s64)xtime.tv_nsec << clock->shift; /* normally this loop will run just once, however in the * case of lost or late ticks, it will accumulate correctly. */ while (offset >= clock->cycle_interval) { /* accumulate one interval */ - clock->xtime_nsec += clock->xtime_interval; - clock->cycle_last += clock->cycle_interval; offset -= clock->cycle_interval; + clock->cycle_last += clock->cycle_interval; + clock->xtime_nsec += clock->xtime_interval; if (clock->xtime_nsec >= (u64)NSEC_PER_SEC << clock->shift) { clock->xtime_nsec -= (u64)NSEC_PER_SEC << clock->shift; xtime.tv_sec++; second_overflow(); } + clock->raw_time.tv_nsec += clock->raw_interval; + if (clock->raw_time.tv_nsec >= NSEC_PER_SEC) { + clock->raw_time.tv_nsec -= NSEC_PER_SEC; + clock->raw_time.tv_sec++; + } + /* accumulate error between NTP and clock interval */ clock->error += tick_length; clock->error -= clock->xtime_interval << (NTP_SCALE_SHIFT - clock->shift); @@ -479,9 +518,12 @@ void update_wall_time(void) /* correct the clock when NTP error is too big */ clocksource_adjust(offset); - /* store full nanoseconds into xtime */ - xtime.tv_nsec = (s64)clock->xtime_nsec >> clock->shift; + /* store full nanoseconds into xtime after rounding it up and + * add the remainder to the error difference. + */ + xtime.tv_nsec = ((s64)clock->xtime_nsec >> clock->shift) + 1; clock->xtime_nsec -= (s64)xtime.tv_nsec << clock->shift; + clock->error += clock->xtime_nsec << (NTP_SCALE_SHIFT - clock->shift); update_xtime_cache(cyc2ns(clock, offset)); diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c index a40e20fd0001..a999b92a1277 100644 --- a/kernel/time/timer_list.c +++ b/kernel/time/timer_list.c @@ -47,13 +47,14 @@ static void print_name_offset(struct seq_file *m, void *sym) } static void -print_timer(struct seq_file *m, struct hrtimer *timer, int idx, u64 now) +print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer, + int idx, u64 now) { #ifdef CONFIG_TIMER_STATS char tmp[TASK_COMM_LEN + 1]; #endif SEQ_printf(m, " #%d: ", idx); - print_name_offset(m, timer); + print_name_offset(m, taddr); SEQ_printf(m, ", "); print_name_offset(m, timer->function); SEQ_printf(m, ", S:%02lx", timer->state); @@ -65,9 +66,11 @@ print_timer(struct seq_file *m, struct hrtimer *timer, int idx, u64 now) SEQ_printf(m, ", %s/%d", tmp, timer->start_pid); #endif SEQ_printf(m, "\n"); - SEQ_printf(m, " # expires at %Lu nsecs [in %Ld nsecs]\n", - (unsigned long long)ktime_to_ns(timer->expires), - (long long)(ktime_to_ns(timer->expires) - now)); + SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n", + (unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)), + (unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)), + (long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now), + (long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now)); } static void @@ -99,7 +102,7 @@ next_one: tmp = *timer; spin_unlock_irqrestore(&base->cpu_base->lock, flags); - print_timer(m, &tmp, i, now); + print_timer(m, timer, &tmp, i, now); next++; goto next_one; } @@ -109,6 +112,7 @@ next_one: static void print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now) { + SEQ_printf(m, " .base: %p\n", base); SEQ_printf(m, " .index: %d\n", base->index); SEQ_printf(m, " .resolution: %Lu nsecs\n", @@ -183,12 +187,16 @@ static void print_cpu(struct seq_file *m, int cpu, u64 now) #ifdef CONFIG_GENERIC_CLOCKEVENTS static void -print_tickdevice(struct seq_file *m, struct tick_device *td) +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"); + else + SEQ_printf(m, "Per CPU device: %d\n", cpu); SEQ_printf(m, "Clock Event Device: "); if (!dev) { @@ -222,7 +230,7 @@ static void timer_list_show_tickdevices(struct seq_file *m) int cpu; #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST - print_tickdevice(m, tick_get_broadcast_device()); + print_tickdevice(m, tick_get_broadcast_device(), -1); SEQ_printf(m, "tick_broadcast_mask: %08lx\n", tick_get_broadcast_mask()->bits[0]); #ifdef CONFIG_TICK_ONESHOT @@ -232,7 +240,7 @@ static void timer_list_show_tickdevices(struct seq_file *m) SEQ_printf(m, "\n"); #endif for_each_online_cpu(cpu) - print_tickdevice(m, tick_get_device(cpu)); + print_tickdevice(m, tick_get_device(cpu), cpu); SEQ_printf(m, "\n"); } #else @@ -244,7 +252,7 @@ static int timer_list_show(struct seq_file *m, void *v) u64 now = ktime_to_ns(ktime_get()); int cpu; - SEQ_printf(m, "Timer List Version: v0.3\n"); + SEQ_printf(m, "Timer List Version: v0.4\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); |