diff options
Diffstat (limited to 'kernel/time')
| -rw-r--r-- | kernel/time/Kconfig | 2 | ||||
| -rw-r--r-- | kernel/time/clockevents.c | 21 | ||||
| -rw-r--r-- | kernel/time/hrtimer.c | 4 | ||||
| -rw-r--r-- | kernel/time/ntp.c | 227 | ||||
| -rw-r--r-- | kernel/time/ntp_internal.h | 1 | ||||
| -rw-r--r-- | kernel/time/posix-cpu-timers.c | 6 | ||||
| -rw-r--r-- | kernel/time/posix-stubs.c | 20 | ||||
| -rw-r--r-- | kernel/time/tick-oneshot.c | 1 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 38 | ||||
| -rw-r--r-- | kernel/time/time.c | 71 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 182 | ||||
| -rw-r--r-- | kernel/time/timekeeping.h | 2 | ||||
| -rw-r--r-- | kernel/time/timer.c | 82 |
13 files changed, 383 insertions, 274 deletions
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index ac09bc29eb08..d689a9557e17 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -56,7 +56,7 @@ menu "Timers subsystem" # Core internal switch. Selected by NO_HZ_COMMON / HIGH_RES_TIMERS. This is # only related to the tick functionality. Oneshot clockevent devices -# are supported independ of this. +# are supported independent of this. config TICK_ONESHOT bool diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 4237e0744e26..16c027e9cc73 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -280,17 +280,22 @@ static int clockevents_program_min_delta(struct clock_event_device *dev) static int clockevents_program_min_delta(struct clock_event_device *dev) { unsigned long long clc; - int64_t delta; + int64_t delta = 0; + int i; - delta = dev->min_delta_ns; - dev->next_event = ktime_add_ns(ktime_get(), delta); + for (i = 0; i < 10; i++) { + delta += dev->min_delta_ns; + dev->next_event = ktime_add_ns(ktime_get(), delta); - if (clockevent_state_shutdown(dev)) - return 0; + if (clockevent_state_shutdown(dev)) + return 0; - dev->retries++; - clc = ((unsigned long long) delta * dev->mult) >> dev->shift; - return dev->set_next_event((unsigned long) clc, dev); + dev->retries++; + clc = ((unsigned long long) delta * dev->mult) >> dev->shift; + if (dev->set_next_event((unsigned long) clc, dev) == 0) + return 0; + } + return -ETIME; } #endif /* CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST */ diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 88f75f92ef36..d32520840fde 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -758,9 +758,7 @@ void clock_was_set(void) */ void hrtimers_resume(void) { - WARN_ONCE(!irqs_disabled(), - KERN_INFO "hrtimers_resume() called with IRQs enabled!"); - + lockdep_assert_irqs_disabled(); /* Retrigger on the local CPU */ retrigger_next_event(NULL); /* And schedule a retrigger for all others */ diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 99e03bec68e4..8d70da1b9a0d 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -493,6 +493,67 @@ out: return leap; } +static void sync_hw_clock(struct work_struct *work); +static DECLARE_DELAYED_WORK(sync_work, sync_hw_clock); + +static void sched_sync_hw_clock(struct timespec64 now, + unsigned long target_nsec, bool fail) + +{ + struct timespec64 next; + + getnstimeofday64(&next); + if (!fail) + next.tv_sec = 659; + else { + /* + * Try again as soon as possible. Delaying long periods + * decreases the accuracy of the work queue timer. Due to this + * the algorithm is very likely to require a short-sleep retry + * after the above long sleep to synchronize ts_nsec. + */ + next.tv_sec = 0; + } + + /* Compute the needed delay that will get to tv_nsec == target_nsec */ + next.tv_nsec = target_nsec - next.tv_nsec; + if (next.tv_nsec <= 0) + next.tv_nsec += NSEC_PER_SEC; + if (next.tv_nsec >= NSEC_PER_SEC) { + next.tv_sec++; + next.tv_nsec -= NSEC_PER_SEC; + } + + queue_delayed_work(system_power_efficient_wq, &sync_work, + timespec64_to_jiffies(&next)); +} + +static void sync_rtc_clock(void) +{ + unsigned long target_nsec; + struct timespec64 adjust, now; + int rc; + + if (!IS_ENABLED(CONFIG_RTC_SYSTOHC)) + return; + + getnstimeofday64(&now); + + adjust = now; + if (persistent_clock_is_local) + adjust.tv_sec -= (sys_tz.tz_minuteswest * 60); + + /* + * The current RTC in use will provide the target_nsec it wants to be + * called at, and does rtc_tv_nsec_ok internally. + */ + rc = rtc_set_ntp_time(adjust, &target_nsec); + if (rc == -ENODEV) + return; + + sched_sync_hw_clock(now, target_nsec, rc); +} + #ifdef CONFIG_GENERIC_CMOS_UPDATE int __weak update_persistent_clock(struct timespec now) { @@ -508,76 +569,75 @@ int __weak update_persistent_clock64(struct timespec64 now64) } #endif -#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) -static void sync_cmos_clock(struct work_struct *work); - -static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock); - -static void sync_cmos_clock(struct work_struct *work) +static bool sync_cmos_clock(void) { + static bool no_cmos; struct timespec64 now; - struct timespec64 next; - int fail = 1; + struct timespec64 adjust; + int rc = -EPROTO; + long target_nsec = NSEC_PER_SEC / 2; + + if (!IS_ENABLED(CONFIG_GENERIC_CMOS_UPDATE)) + return false; + + if (no_cmos) + return false; /* - * If we have an externally synchronized Linux clock, then update - * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be - * called as close as possible to 500 ms before the new second starts. - * This code is run on a timer. If the clock is set, that timer - * may not expire at the correct time. Thus, we adjust... - * We want the clock to be within a couple of ticks from the target. + * Historically update_persistent_clock64() has followed x86 + * semantics, which match the MC146818A/etc RTC. This RTC will store + * 'adjust' and then in .5s it will advance once second. + * + * Architectures are strongly encouraged to use rtclib and not + * implement this legacy API. */ - if (!ntp_synced()) { - /* - * Not synced, exit, do not restart a timer (if one is - * running, let it run out). - */ - return; - } - getnstimeofday64(&now); - if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec * 5) { - struct timespec64 adjust = now; - - fail = -ENODEV; + if (rtc_tv_nsec_ok(-1 * target_nsec, &adjust, &now)) { if (persistent_clock_is_local) adjust.tv_sec -= (sys_tz.tz_minuteswest * 60); -#ifdef CONFIG_GENERIC_CMOS_UPDATE - fail = update_persistent_clock64(adjust); -#endif - -#ifdef CONFIG_RTC_SYSTOHC - if (fail == -ENODEV) - fail = rtc_set_ntp_time(adjust); -#endif + rc = update_persistent_clock64(adjust); + /* + * The machine does not support update_persistent_clock64 even + * though it defines CONFIG_GENERIC_CMOS_UPDATE. + */ + if (rc == -ENODEV) { + no_cmos = true; + return false; + } } - next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec - (TICK_NSEC / 2); - if (next.tv_nsec <= 0) - next.tv_nsec += NSEC_PER_SEC; + sched_sync_hw_clock(now, target_nsec, rc); + return true; +} - if (!fail || fail == -ENODEV) - next.tv_sec = 659; - else - next.tv_sec = 0; +/* + * If we have an externally synchronized Linux clock, then update RTC clock + * accordingly every ~11 minutes. Generally RTCs can only store second + * precision, but many RTCs will adjust the phase of their second tick to + * match the moment of update. This infrastructure arranges to call to the RTC + * set at the correct moment to phase synchronize the RTC second tick over + * with the kernel clock. + */ +static void sync_hw_clock(struct work_struct *work) +{ + if (!ntp_synced()) + return; - if (next.tv_nsec >= NSEC_PER_SEC) { - next.tv_sec++; - next.tv_nsec -= NSEC_PER_SEC; - } - queue_delayed_work(system_power_efficient_wq, - &sync_cmos_work, timespec64_to_jiffies(&next)); + if (sync_cmos_clock()) + return; + + sync_rtc_clock(); } void ntp_notify_cmos_timer(void) { - queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0); -} - -#else -void ntp_notify_cmos_timer(void) { } -#endif + if (!ntp_synced()) + return; + if (IS_ENABLED(CONFIG_GENERIC_CMOS_UPDATE) || + IS_ENABLED(CONFIG_RTC_SYSTOHC)) + queue_delayed_work(system_power_efficient_wq, &sync_work, 0); +} /* * Propagate a new txc->status value into the NTP state: @@ -654,67 +714,6 @@ static inline void process_adjtimex_modes(struct timex *txc, } - -/** - * ntp_validate_timex - Ensures the timex is ok for use in do_adjtimex - */ -int ntp_validate_timex(struct timex *txc) -{ - if (txc->modes & ADJ_ADJTIME) { - /* singleshot must not be used with any other mode bits */ - 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% then - * 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_SETOFFSET) { - /* In order to inject time, you gotta be super-user! */ - if (!capable(CAP_SYS_TIME)) - return -EPERM; - - if (txc->modes & ADJ_NANO) { - struct timespec ts; - - ts.tv_sec = txc->time.tv_sec; - ts.tv_nsec = txc->time.tv_usec; - if (!timespec_inject_offset_valid(&ts)) - return -EINVAL; - - } else { - if (!timeval_inject_offset_valid(&txc->time)) - return -EINVAL; - } - } - - /* - * Check for potential multiplication overflows that can - * only happen on 64-bit systems: - */ - if ((txc->modes & ADJ_FREQUENCY) && (BITS_PER_LONG == 64)) { - if (LLONG_MIN / PPM_SCALE > txc->freq) - return -EINVAL; - if (LLONG_MAX / PPM_SCALE < txc->freq) - return -EINVAL; - } - - return 0; -} - - /* * adjtimex mainly allows reading (and writing, if superuser) of * kernel time-keeping variables. used by xntpd. diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h index 0a53e6ea47b1..909bd1f1bfb1 100644 --- a/kernel/time/ntp_internal.h +++ b/kernel/time/ntp_internal.h @@ -8,7 +8,6 @@ extern void ntp_clear(void); extern u64 ntp_tick_length(void); extern ktime_t ntp_get_next_leap(void); extern int second_overflow(time64_t secs); -extern int ntp_validate_timex(struct timex *); extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *); extern void __hardpps(const struct timespec64 *, const struct timespec64 *); #endif /* _LINUX_NTP_INTERNAL_H */ diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index 5b117110b55b..1f27887aa194 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -603,7 +603,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags, /* * Disarm any old timer after extracting its expiry time. */ - WARN_ON_ONCE(!irqs_disabled()); + lockdep_assert_irqs_disabled(); ret = 0; old_incr = timer->it.cpu.incr; @@ -1034,7 +1034,7 @@ static void posix_cpu_timer_rearm(struct k_itimer *timer) /* * Now re-arm for the new expiry time. */ - WARN_ON_ONCE(!irqs_disabled()); + lockdep_assert_irqs_disabled(); arm_timer(timer); unlock: unlock_task_sighand(p, &flags); @@ -1125,7 +1125,7 @@ void run_posix_cpu_timers(struct task_struct *tsk) struct k_itimer *timer, *next; unsigned long flags; - WARN_ON_ONCE(!irqs_disabled()); + lockdep_assert_irqs_disabled(); /* * The fast path checks that there are no expired thread or thread diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c index 06f34feb635e..b258bee13b02 100644 --- a/kernel/time/posix-stubs.c +++ b/kernel/time/posix-stubs.c @@ -117,8 +117,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, const struct timespec __user *, rqtp, struct timespec __user *, rmtp) { - struct timespec64 t64; - struct timespec t; + struct timespec64 t; switch (which_clock) { case CLOCK_REALTIME: @@ -129,16 +128,15 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, return -EINVAL; } - if (copy_from_user(&t, rqtp, sizeof (struct timespec))) + if (get_timespec64(&t, rqtp)) return -EFAULT; - t64 = timespec_to_timespec64(t); - if (!timespec64_valid(&t64)) + if (!timespec64_valid(&t)) return -EINVAL; if (flags & TIMER_ABSTIME) rmtp = NULL; current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE; current->restart_block.nanosleep.rmtp = rmtp; - return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ? + return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL, which_clock); } @@ -203,8 +201,7 @@ COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags, struct compat_timespec __user *, rqtp, struct compat_timespec __user *, rmtp) { - struct timespec64 t64; - struct timespec t; + struct timespec64 t; switch (which_clock) { case CLOCK_REALTIME: @@ -215,16 +212,15 @@ COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags, return -EINVAL; } - if (compat_get_timespec(&t, rqtp)) + if (compat_get_timespec64(&t, rqtp)) return -EFAULT; - t64 = timespec_to_timespec64(t); - if (!timespec64_valid(&t64)) + if (!timespec64_valid(&t)) return -EINVAL; if (flags & TIMER_ABSTIME) rmtp = NULL; current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE; current->restart_block.nanosleep.compat_rmtp = rmtp; - return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ? + return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL, which_clock); } diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c index 6b009c207671..c1f518e7aa80 100644 --- a/kernel/time/tick-oneshot.c +++ b/kernel/time/tick-oneshot.c @@ -33,6 +33,7 @@ int tick_program_event(ktime_t expires, int force) * We don't need the clock event device any more, stop it. */ clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT_STOPPED); + dev->next_event = KTIME_MAX; return 0; } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index c7a899c5ce64..99578f06c8d4 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -27,6 +27,7 @@ #include <linux/irq_work.h> #include <linux/posix-timers.h> #include <linux/context_tracking.h> +#include <linux/mm.h> #include <asm/irq_regs.h> @@ -165,7 +166,6 @@ static void tick_sched_handle(struct tick_sched *ts, struct pt_regs *regs) #ifdef CONFIG_NO_HZ_FULL cpumask_var_t tick_nohz_full_mask; -cpumask_var_t housekeeping_mask; bool tick_nohz_full_running; static atomic_t tick_dep_mask; @@ -198,7 +198,7 @@ static bool check_tick_dependency(atomic_t *dep) static bool can_stop_full_tick(int cpu, struct tick_sched *ts) { - WARN_ON_ONCE(!irqs_disabled()); + lockdep_assert_irqs_disabled(); if (unlikely(!cpu_online(cpu))) return false; @@ -385,20 +385,13 @@ out: local_irq_restore(flags); } -/* Parse the boot-time nohz CPU list from the kernel parameters. */ -static int __init tick_nohz_full_setup(char *str) +/* Get the boot-time nohz CPU list from the kernel parameters. */ +void __init tick_nohz_full_setup(cpumask_var_t cpumask) { alloc_bootmem_cpumask_var(&tick_nohz_full_mask); - if (cpulist_parse(str, tick_nohz_full_mask) < 0) { - pr_warn("NO_HZ: Incorrect nohz_full cpumask\n"); - free_bootmem_cpumask_var(tick_nohz_full_mask); - return 1; - } + cpumask_copy(tick_nohz_full_mask, cpumask); tick_nohz_full_running = true; - - return 1; } -__setup("nohz_full=", tick_nohz_full_setup); static int tick_nohz_cpu_down(unsigned int cpu) { @@ -437,13 +430,6 @@ void __init tick_nohz_init(void) return; } - if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) { - WARN(1, "NO_HZ: Can't allocate not-full dynticks cpumask\n"); - cpumask_clear(tick_nohz_full_mask); - tick_nohz_full_running = false; - return; - } - /* * Full dynticks uses irq work to drive the tick rescheduling on safe * locking contexts. But then we need irq work to raise its own @@ -452,7 +438,6 @@ void __init tick_nohz_init(void) if (!arch_irq_work_has_interrupt()) { pr_warn("NO_HZ: Can't run full dynticks because arch doesn't support irq work self-IPIs\n"); cpumask_clear(tick_nohz_full_mask); - cpumask_copy(housekeeping_mask, cpu_possible_mask); tick_nohz_full_running = false; return; } @@ -465,9 +450,6 @@ void __init tick_nohz_init(void) cpumask_clear_cpu(cpu, tick_nohz_full_mask); } - cpumask_andnot(housekeeping_mask, - cpu_possible_mask, tick_nohz_full_mask); - for_each_cpu(cpu, tick_nohz_full_mask) context_tracking_cpu_set(cpu); @@ -477,12 +459,6 @@ void __init tick_nohz_init(void) WARN_ON(ret < 0); pr_info("NO_HZ: Full dynticks CPUs: %*pbl.\n", cpumask_pr_args(tick_nohz_full_mask)); - - /* - * We need at least one CPU to handle housekeeping work such - * as timekeeping, unbound timers, workqueues, ... - */ - WARN_ON_ONCE(cpumask_empty(housekeeping_mask)); } #endif @@ -787,6 +763,7 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts, if (!ts->tick_stopped) { calc_load_nohz_start(); cpu_load_update_nohz_start(); + quiet_vmstat(); ts->last_tick = hrtimer_get_expires(&ts->sched_timer); ts->tick_stopped = 1; @@ -960,8 +937,7 @@ void tick_nohz_idle_enter(void) { struct tick_sched *ts; - WARN_ON_ONCE(irqs_disabled()); - + lockdep_assert_irqs_enabled(); /* * Update the idle state in the scheduler domain hierarchy * when tick_nohz_stop_sched_tick() is called from the idle loop. diff --git a/kernel/time/time.c b/kernel/time/time.c index 44a8c1402133..bd4e6c7dd689 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -82,7 +82,7 @@ SYSCALL_DEFINE1(time, time_t __user *, tloc) SYSCALL_DEFINE1(stime, time_t __user *, tptr) { - struct timespec tv; + struct timespec64 tv; int err; if (get_user(tv.tv_sec, tptr)) @@ -90,11 +90,11 @@ SYSCALL_DEFINE1(stime, time_t __user *, tptr) tv.tv_nsec = 0; - err = security_settime(&tv, NULL); + err = security_settime64(&tv, NULL); if (err) return err; - do_settimeofday(&tv); + do_settimeofday64(&tv); return 0; } @@ -122,7 +122,7 @@ COMPAT_SYSCALL_DEFINE1(time, compat_time_t __user *, tloc) COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr) { - struct timespec tv; + struct timespec64 tv; int err; if (get_user(tv.tv_sec, tptr)) @@ -130,11 +130,11 @@ COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr) tv.tv_nsec = 0; - err = security_settime(&tv, NULL); + err = security_settime64(&tv, NULL); if (err) return err; - do_settimeofday(&tv); + do_settimeofday64(&tv); return 0; } @@ -158,40 +158,6 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv, } /* - * Indicates if there is an offset between the system clock and the hardware - * clock/persistent clock/rtc. - */ -int persistent_clock_is_local; - -/* - * Adjust the time obtained from the CMOS to be UTC time instead of - * local time. - * - * This is ugly, but preferable to the alternatives. Otherwise we - * would either need to write a program to do it in /etc/rc (and risk - * confusion if the program gets run more than once; it would also be - * hard to make the program warp the clock precisely n hours) or - * compile in the timezone information into the kernel. Bad, bad.... - * - * - TYT, 1992-01-01 - * - * The best thing to do is to keep the CMOS clock in universal time (UTC) - * as real UNIX machines always do it. This avoids all headaches about - * daylight saving times and warping kernel clocks. - */ -static inline void warp_clock(void) -{ - if (sys_tz.tz_minuteswest != 0) { - struct timespec adjust; - - persistent_clock_is_local = 1; - adjust.tv_sec = sys_tz.tz_minuteswest * 60; - adjust.tv_nsec = 0; - timekeeping_inject_offset(&adjust); - } -} - -/* * In case for some reason the CMOS clock has not already been running * in UTC, but in some local time: The first time we set the timezone, * we will warp the clock so that it is ticking UTC time instead of @@ -224,7 +190,7 @@ int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz if (firsttime) { firsttime = 0; if (!tv) - warp_clock(); + timekeeping_warp_clock(); } } if (tv) @@ -441,6 +407,7 @@ time64_t mktime64(const unsigned int year0, const unsigned int mon0, } EXPORT_SYMBOL(mktime64); +#if __BITS_PER_LONG == 32 /** * set_normalized_timespec - set timespec sec and nsec parts and normalize * @@ -501,6 +468,7 @@ struct timespec ns_to_timespec(const s64 nsec) return ts; } EXPORT_SYMBOL(ns_to_timespec); +#endif /** * ns_to_timeval - Convert nanoseconds to timeval @@ -520,7 +488,6 @@ struct timeval ns_to_timeval(const s64 nsec) } EXPORT_SYMBOL(ns_to_timeval); -#if BITS_PER_LONG == 32 /** * set_normalized_timespec - set timespec sec and nsec parts and normalize * @@ -581,7 +548,7 @@ struct timespec64 ns_to_timespec64(const s64 nsec) return ts; } EXPORT_SYMBOL(ns_to_timespec64); -#endif + /** * msecs_to_jiffies: - convert milliseconds to jiffies * @m: time in milliseconds @@ -853,24 +820,6 @@ unsigned long nsecs_to_jiffies(u64 n) EXPORT_SYMBOL_GPL(nsecs_to_jiffies); /* - * Add two timespec values and do a safety check for overflow. - * It's assumed that both values are valid (>= 0) - */ -struct timespec timespec_add_safe(const struct timespec lhs, - const struct timespec rhs) -{ - struct timespec res; - - set_normalized_timespec(&res, lhs.tv_sec + rhs.tv_sec, - lhs.tv_nsec + rhs.tv_nsec); - - if (res.tv_sec < lhs.tv_sec || res.tv_sec < rhs.tv_sec) - res.tv_sec = TIME_T_MAX; - - return res; -} - -/* * Add two timespec64 values and do a safety check for overflow. * It's assumed that both values are valid (>= 0). * And, each timespec64 is in normalized form. diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 2cafb49aa65e..198afa78bf69 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -60,8 +60,27 @@ struct tk_fast { struct tk_read_base base[2]; }; -static struct tk_fast tk_fast_mono ____cacheline_aligned; -static struct tk_fast tk_fast_raw ____cacheline_aligned; +/* Suspend-time cycles value for halted fast timekeeper. */ +static u64 cycles_at_suspend; + +static u64 dummy_clock_read(struct clocksource *cs) +{ + return cycles_at_suspend; +} + +static struct clocksource dummy_clock = { + .read = dummy_clock_read, +}; + +static struct tk_fast tk_fast_mono ____cacheline_aligned = { + .base[0] = { .clock = &dummy_clock, }, + .base[1] = { .clock = &dummy_clock, }, +}; + +static struct tk_fast tk_fast_raw ____cacheline_aligned = { + .base[0] = { .clock = &dummy_clock, }, + .base[1] = { .clock = &dummy_clock, }, +}; /* flag for if timekeeping is suspended */ int __read_mostly timekeeping_suspended; @@ -477,17 +496,39 @@ u64 notrace ktime_get_boot_fast_ns(void) } EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns); -/* Suspend-time cycles value for halted fast timekeeper. */ -static u64 cycles_at_suspend; -static u64 dummy_clock_read(struct clocksource *cs) +/* + * See comment for __ktime_get_fast_ns() vs. timestamp ordering + */ +static __always_inline u64 __ktime_get_real_fast_ns(struct tk_fast *tkf) { - return cycles_at_suspend; + struct tk_read_base *tkr; + unsigned int seq; + u64 now; + + do { + seq = raw_read_seqcount_latch(&tkf->seq); + tkr = tkf->base + (seq & 0x01); + now = ktime_to_ns(tkr->base_real); + + now += timekeeping_delta_to_ns(tkr, + clocksource_delta( + tk_clock_read(tkr), + tkr->cycle_last, + tkr->mask)); + } while (read_seqcount_retry(&tkf->seq, seq)); + + return now; } -static struct clocksource dummy_clock = { - .read = dummy_clock_read, -}; +/** + * ktime_get_real_fast_ns: - NMI safe and fast access to clock realtime. + */ +u64 ktime_get_real_fast_ns(void) +{ + return __ktime_get_real_fast_ns(&tk_fast_mono); +} +EXPORT_SYMBOL_GPL(ktime_get_real_fast_ns); /** * halt_fast_timekeeper - Prevent fast timekeeper from accessing clocksource. @@ -507,6 +548,7 @@ static void halt_fast_timekeeper(struct timekeeper *tk) memcpy(&tkr_dummy, tkr, sizeof(tkr_dummy)); cycles_at_suspend = tk_clock_read(tkr); tkr_dummy.clock = &dummy_clock; + tkr_dummy.base_real = tkr->base + tk->offs_real; update_fast_timekeeper(&tkr_dummy, &tk_fast_mono); tkr = &tk->tkr_raw; @@ -654,6 +696,7 @@ static void timekeeping_update(struct timekeeper *tk, unsigned int action) update_vsyscall(tk); update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET); + tk->tkr_mono.base_real = tk->tkr_mono.base + tk->offs_real; update_fast_timekeeper(&tk->tkr_mono, &tk_fast_mono); update_fast_timekeeper(&tk->tkr_raw, &tk_fast_raw); @@ -1264,33 +1307,31 @@ EXPORT_SYMBOL(do_settimeofday64); * * Adds or subtracts an offset value from the current time. */ -int timekeeping_inject_offset(struct timespec *ts) +static int timekeeping_inject_offset(struct timespec64 *ts) { struct timekeeper *tk = &tk_core.timekeeper; unsigned long flags; - struct timespec64 ts64, tmp; + struct timespec64 tmp; int ret = 0; - if (!timespec_inject_offset_valid(ts)) + if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC) return -EINVAL; - ts64 = timespec_to_timespec64(*ts); - raw_spin_lock_irqsave(&timekeeper_lock, flags); write_seqcount_begin(&tk_core.seq); timekeeping_forward_now(tk); /* Make sure the proposed value is valid */ - tmp = timespec64_add(tk_xtime(tk), ts64); - if (timespec64_compare(&tk->wall_to_monotonic, &ts64) > 0 || + tmp = timespec64_add(tk_xtime(tk), *ts); + if (timespec64_compare(&tk->wall_to_monotonic, ts) > 0 || !timespec64_valid_strict(&tmp)) { ret = -EINVAL; goto error; } - tk_xtime_add(tk, &ts64); - tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts64)); + tk_xtime_add(tk, ts); + tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, *ts)); error: /* even if we error out, we forwarded the time, so call update */ timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET); @@ -1303,7 +1344,40 @@ error: /* even if we error out, we forwarded the time, so call update */ return ret; } -EXPORT_SYMBOL(timekeeping_inject_offset); + +/* + * Indicates if there is an offset between the system clock and the hardware + * clock/persistent clock/rtc. + */ +int persistent_clock_is_local; + +/* + * Adjust the time obtained from the CMOS to be UTC time instead of + * local time. + * + * This is ugly, but preferable to the alternatives. Otherwise we + * would either need to write a program to do it in /etc/rc (and risk + * confusion if the program gets run more than once; it would also be + * hard to make the program warp the clock precisely n hours) or + * compile in the timezone information into the kernel. Bad, bad.... + * + * - TYT, 1992-01-01 + * + * The best thing to do is to keep the CMOS clock in universal time (UTC) + * as real UNIX machines always do it. This avoids all headaches about + * daylight saving times and warping kernel clocks. + */ +void timekeeping_warp_clock(void) +{ + if (sys_tz.tz_minuteswest != 0) { + struct timespec64 adjust; + + persistent_clock_is_local = 1; + adjust.tv_sec = sys_tz.tz_minuteswest * 60; + adjust.tv_nsec = 0; + timekeeping_inject_offset(&adjust); + } +} /** * __timekeeping_set_tai_offset - Sets the TAI offset from UTC and monotonic @@ -2248,6 +2322,72 @@ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real, } /** + * timekeeping_validate_timex - Ensures the timex is ok for use in do_adjtimex + */ +static int timekeeping_validate_timex(struct timex *txc) +{ + if (txc->modes & ADJ_ADJTIME) { + /* singleshot must not be used with any other mode bits */ + 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% then + * 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_SETOFFSET) { + /* In order to inject time, you gotta be super-user! */ + if (!capable(CAP_SYS_TIME)) + return -EPERM; + + /* + * Validate if a timespec/timeval used to inject a time + * offset is valid. Offsets can be postive or negative, so + * we don't check tv_sec. The value of the timeval/timespec + * is the sum of its fields,but *NOTE*: + * The field tv_usec/tv_nsec must always be non-negative and + * we can't have more nanoseconds/microseconds than a second. + */ + if (txc->time.tv_usec < 0) + return -EINVAL; + + if (txc->modes & ADJ_NANO) { + if (txc->time.tv_usec >= NSEC_PER_SEC) + return -EINVAL; + } else { + if (txc->time.tv_usec >= USEC_PER_SEC) + return -EINVAL; + } + } + + /* + * Check for potential multiplication overflows that can + * only happen on 64-bit systems: + */ + if ((txc->modes & ADJ_FREQUENCY) && (BITS_PER_LONG == 64)) { + if (LLONG_MIN / PPM_SCALE > txc->freq) + return -EINVAL; + if (LLONG_MAX / PPM_SCALE < txc->freq) + return -EINVAL; + } + + return 0; +} + + +/** * do_adjtimex() - Accessor function to NTP __do_adjtimex function */ int do_adjtimex(struct timex *txc) @@ -2259,12 +2399,12 @@ int do_adjtimex(struct timex *txc) int ret; /* Validate the data before disabling interrupts */ - ret = ntp_validate_timex(txc); + ret = timekeeping_validate_timex(txc); if (ret) return ret; if (txc->modes & ADJ_SETOFFSET) { - struct timespec delta; + struct timespec64 delta; delta.tv_sec = txc->time.tv_sec; delta.tv_nsec = txc->time.tv_usec; if (!(txc->modes & ADJ_NANO)) diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h index c9f9af339914..7a9b4eb7a1d5 100644 --- a/kernel/time/timekeeping.h +++ b/kernel/time/timekeeping.h @@ -11,7 +11,7 @@ extern ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, extern int timekeeping_valid_for_hres(void); extern u64 timekeeping_max_deferment(void); -extern int timekeeping_inject_offset(struct timespec *ts); +extern void timekeeping_warp_clock(void); extern int timekeeping_suspend(void); extern void timekeeping_resume(void); diff --git a/kernel/time/timer.c b/kernel/time/timer.c index f2674a056c26..af0b8bae4502 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -610,7 +610,7 @@ static bool timer_fixup_init(void *addr, enum debug_obj_state state) } /* Stub timer callback for improperly used timers. */ -static void stub_timer(unsigned long data) +static void stub_timer(struct timer_list *unused) { WARN_ON(1); } @@ -626,7 +626,7 @@ static bool timer_fixup_activate(void *addr, enum debug_obj_state state) switch (state) { case ODEBUG_STATE_NOTAVAILABLE: - setup_timer(timer, stub_timer, 0); + timer_setup(timer, stub_timer, 0); return true; case ODEBUG_STATE_ACTIVE: @@ -665,7 +665,7 @@ static bool timer_fixup_assert_init(void *addr, enum debug_obj_state state) switch (state) { case ODEBUG_STATE_NOTAVAILABLE: - setup_timer(timer, stub_timer, 0); + timer_setup(timer, stub_timer, 0); return true; default: return false; @@ -929,8 +929,11 @@ static struct timer_base *lock_timer_base(struct timer_list *timer, } } +#define MOD_TIMER_PENDING_ONLY 0x01 +#define MOD_TIMER_REDUCE 0x02 + static inline int -__mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only) +__mod_timer(struct timer_list *timer, unsigned long expires, unsigned int options) { struct timer_base *base, *new_base; unsigned int idx = UINT_MAX; @@ -950,7 +953,11 @@ __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only) * larger granularity than you would get from adding a new * timer with this expiry. */ - if (timer->expires == expires) + long diff = timer->expires - expires; + + if (!diff) + return 1; + if (options & MOD_TIMER_REDUCE && diff <= 0) return 1; /* @@ -962,6 +969,12 @@ __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only) base = lock_timer_base(timer, &flags); forward_timer_base(base); + if (timer_pending(timer) && (options & MOD_TIMER_REDUCE) && + time_before_eq(timer->expires, expires)) { + ret = 1; + goto out_unlock; + } + clk = base->clk; idx = calc_wheel_index(expires, clk); @@ -971,7 +984,10 @@ __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only) * subsequent call will exit in the expires check above. */ if (idx == timer_get_idx(timer)) { - timer->expires = expires; + if (!(options & MOD_TIMER_REDUCE)) + timer->expires = expires; + else if (time_after(timer->expires, expires)) + timer->expires = expires; ret = 1; goto out_unlock; } @@ -981,7 +997,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only) } ret = detach_if_pending(timer, base, false); - if (!ret && pending_only) + if (!ret && (options & MOD_TIMER_PENDING_ONLY)) goto out_unlock; debug_activate(timer, expires); @@ -1042,7 +1058,7 @@ out_unlock: */ int mod_timer_pending(struct timer_list *timer, unsigned long expires) { - return __mod_timer(timer, expires, true); + return __mod_timer(timer, expires, MOD_TIMER_PENDING_ONLY); } EXPORT_SYMBOL(mod_timer_pending); @@ -1068,11 +1084,26 @@ EXPORT_SYMBOL(mod_timer_pending); */ int mod_timer(struct timer_list *timer, unsigned long expires) { - return __mod_timer(timer, expires, false); + return __mod_timer(timer, expires, 0); } EXPORT_SYMBOL(mod_timer); /** + * timer_reduce - Modify a timer's timeout if it would reduce the timeout + * @timer: The timer to be modified + * @expires: New timeout in jiffies + * + * timer_reduce() is very similar to mod_timer(), except that it will only + * modify a running timer if that would reduce the expiration time (it will + * start a timer that isn't running). + */ +int timer_reduce(struct timer_list *timer, unsigned long expires) +{ + return __mod_timer(timer, expires, MOD_TIMER_REDUCE); +} +EXPORT_SYMBOL(timer_reduce); + +/** * add_timer - start a timer * @timer: the timer to be added * @@ -1560,8 +1591,11 @@ static int collect_expired_timers(struct timer_base *base, * jiffies, otherwise forward to the next expiry time: */ if (time_after(next, jiffies)) { - /* The call site will increment clock! */ - base->clk = jiffies - 1; + /* + * The call site will increment base->clk and then + * terminate the expiry loop immediately. + */ + base->clk = jiffies; return 0; } base->clk = next; @@ -1668,9 +1702,20 @@ void run_local_timers(void) raise_softirq(TIMER_SOFTIRQ); } -static void process_timeout(unsigned long __data) +/* + * Since schedule_timeout()'s timer is defined on the stack, it must store + * the target task on the stack as well. + */ +struct process_timer { + struct timer_list timer; + struct task_struct *task; +}; + +static void process_timeout(struct timer_list *t) { - wake_up_process((struct task_struct *)__data); + struct process_timer *timeout = from_timer(timeout, t, timer); + + wake_up_process(timeout->task); } /** @@ -1704,7 +1749,7 @@ static void process_timeout(unsigned long __data) */ signed long __sched schedule_timeout(signed long timeout) { - struct timer_list timer; + struct process_timer timer; unsigned long expire; switch (timeout) @@ -1738,13 +1783,14 @@ signed long __sched schedule_timeout(signed long timeout) expire = timeout + jiffies; - setup_timer_on_stack(&timer, process_timeout, (unsigned long)current); - __mod_timer(&timer, expire, false); + timer.task = current; + timer_setup_on_stack(&timer.timer, process_timeout, 0); + __mod_timer(&timer.timer, expire, 0); schedule(); - del_singleshot_timer_sync(&timer); + del_singleshot_timer_sync(&timer.timer); /* Remove the timer from the object tracker */ - destroy_timer_on_stack(&timer); + destroy_timer_on_stack(&timer.timer); timeout = expire - jiffies; |