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-rw-r--r--kernel/time/Kconfig58
-rw-r--r--kernel/time/alarmtimer.c4
-rw-r--r--kernel/time/clockevents.c3
-rw-r--r--kernel/time/ntp.c14
-rw-r--r--kernel/time/tick-sched.c28
-rw-r--r--kernel/time/timekeeping.c68
6 files changed, 152 insertions, 23 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 e8c867173ae..b7fbadc5c97 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -409,7 +409,9 @@ int second_overflow(unsigned long secs)
time_state = TIME_DEL;
break;
case TIME_INS:
- if (secs % 86400 == 0) {
+ if (!(time_status & STA_INS))
+ time_state = TIME_OK;
+ else if (secs % 86400 == 0) {
leap = -1;
time_state = TIME_OOP;
time_tai++;
@@ -418,7 +420,9 @@ int second_overflow(unsigned long secs)
}
break;
case TIME_DEL:
- if ((secs + 1) % 86400 == 0) {
+ if (!(time_status & STA_DEL))
+ time_state = TIME_OK;
+ else if ((secs + 1) % 86400 == 0) {
leap = 1;
time_tai--;
time_state = TIME_WAIT;
@@ -473,8 +477,6 @@ int second_overflow(unsigned long secs)
<< NTP_SCALE_SHIFT;
time_adjust = 0;
-
-
out:
spin_unlock_irqrestore(&ntp_lock, flags);
@@ -559,10 +561,10 @@ 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-sched.c b/kernel/time/tick-sched.c
index 6a3a5b9ff56..4a08472c3ca 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
@@ -401,6 +406,7 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
*/
if (!ts->tick_stopped) {
select_nohz_load_balancer(1);
+ calc_load_enter_idle();
ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
ts->tick_stopped = 1;
@@ -576,6 +582,7 @@ 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
/*
@@ -591,6 +598,7 @@ void tick_nohz_idle_exit(void)
account_idle_ticks(ticks);
#endif
+ calc_load_exit_idle();
touch_softlockup_watchdog();
/*
* Cancel the scheduled timer and restore the tick
@@ -814,6 +822,16 @@ 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 +849,14 @@ 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 d42574df7c5..3447cfaf11e 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -70,6 +70,12 @@ struct timekeeper {
/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
struct timespec raw_time;
+ /* Offset clock monotonic -> clock realtime */
+ ktime_t offs_real;
+
+ /* Offset clock monotonic -> clock boottime */
+ ktime_t offs_boot;
+
/* Seqlock for all timekeeper values */
seqlock_t lock;
};
@@ -172,6 +178,14 @@ static inline s64 timekeeping_get_ns_raw(void)
return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
}
+static void update_rt_offset(void)
+{
+ struct timespec tmp, *wtm = &timekeeper.wall_to_monotonic;
+
+ set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec);
+ timekeeper.offs_real = timespec_to_ktime(tmp);
+}
+
/* must hold write on timekeeper.lock */
static void timekeeping_update(bool clearntp)
{
@@ -179,6 +193,7 @@ static void timekeeping_update(bool clearntp)
timekeeper.ntp_error = 0;
ntp_clear();
}
+ update_rt_offset();
update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
timekeeper.clock, timekeeper.mult);
}
@@ -240,7 +255,6 @@ void getnstimeofday(struct timespec *ts)
timespec_add_ns(ts, nsecs);
}
-
EXPORT_SYMBOL(getnstimeofday);
ktime_t ktime_get(void)
@@ -357,8 +371,8 @@ 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 +406,6 @@ int do_settimeofday(const struct timespec *tv)
return 0;
}
-
EXPORT_SYMBOL(do_settimeofday);
@@ -606,6 +619,7 @@ void __init timekeeping_init(void)
}
set_normalized_timespec(&timekeeper.wall_to_monotonic,
-boot.tv_sec, -boot.tv_nsec);
+ update_rt_offset();
timekeeper.total_sleep_time.tv_sec = 0;
timekeeper.total_sleep_time.tv_nsec = 0;
write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -614,6 +628,12 @@ void __init timekeeping_init(void)
/* time in seconds when suspend began */
static struct timespec timekeeping_suspend_time;
+static void update_sleep_time(struct timespec t)
+{
+ timekeeper.total_sleep_time = t;
+ timekeeper.offs_boot = timespec_to_ktime(t);
+}
+
/**
* __timekeeping_inject_sleeptime - Internal function to add sleep interval
* @delta: pointer to a timespec delta value
@@ -632,8 +652,7 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
timekeeper.xtime = timespec_add(timekeeper.xtime, *delta);
timekeeper.wall_to_monotonic =
timespec_sub(timekeeper.wall_to_monotonic, *delta);
- timekeeper.total_sleep_time = timespec_add(
- timekeeper.total_sleep_time, *delta);
+ update_sleep_time(timespec_add(timekeeper.total_sleep_time, *delta));
}
@@ -698,6 +717,7 @@ static void timekeeping_resume(void)
timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
timekeeper.ntp_error = 0;
timekeeping_suspended = 0;
+ timekeeping_update(false);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
touch_softlockup_watchdog();
@@ -965,6 +985,8 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
leap = second_overflow(timekeeper.xtime.tv_sec);
timekeeper.xtime.tv_sec += leap;
timekeeper.wall_to_monotonic.tv_sec -= leap;
+ if (leap)
+ clock_was_set_delayed();
}
/* Accumulate raw time */
@@ -1081,6 +1103,8 @@ static void update_wall_time(void)
leap = second_overflow(timekeeper.xtime.tv_sec);
timekeeper.xtime.tv_sec += leap;
timekeeper.wall_to_monotonic.tv_sec -= leap;
+ if (leap)
+ clock_was_set_delayed();
}
timekeeping_update(false);
@@ -1248,6 +1272,40 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
} while (read_seqretry(&timekeeper.lock, seq));
}
+#ifdef CONFIG_HIGH_RES_TIMERS
+/**
+ * ktime_get_update_offsets - hrtimer helper
+ * @offs_real: pointer to storage for monotonic -> realtime offset
+ * @offs_boot: pointer to storage for monotonic -> boottime offset
+ *
+ * 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 now;
+ unsigned int seq;
+ u64 secs, nsecs;
+
+ do {
+ seq = read_seqbegin(&timekeeper.lock);
+
+ secs = timekeeper.xtime.tv_sec;
+ nsecs = timekeeper.xtime.tv_nsec;
+ nsecs += timekeeping_get_ns();
+ /* If arch requires, add in gettimeoffset() */
+ nsecs += arch_gettimeoffset();
+
+ *offs_real = timekeeper.offs_real;
+ *offs_boot = timekeeper.offs_boot;
+ } while (read_seqretry(&timekeeper.lock, seq));
+
+ now = ktime_add_ns(ktime_set(secs, 0), nsecs);
+ now = ktime_sub(now, *offs_real);
+ return now;
+}
+#endif
+
/**
* ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format
*/