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authorAnton Arapov <anton@redhat.com>2012-06-08 12:58:00 +0200
committerAnton Arapov <anton@redhat.com>2012-06-08 12:58:00 +0200
commit6792a3f47a2e42d7164292bf7f1a55cfc4c91652 (patch)
treeb90c002bfbbeaec92f5d8a2383dcabf6524016f7 /kernel/time
parentfe2895d3d55146cac65b273c0f83e2c7e543cd0e (diff)
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fedora kernel: b920e9b748c595f970bf80ede7832d39f8d567dav3.4.1-2
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'kernel/time')
-rw-r--r--kernel/time/Kconfig4
-rw-r--r--kernel/time/alarmtimer.c8
-rw-r--r--kernel/time/clocksource.c2
-rw-r--r--kernel/time/ntp.c189
-rw-r--r--kernel/time/tick-broadcast.c9
-rw-r--r--kernel/time/tick-sched.c17
-rw-r--r--kernel/time/timekeeping.c372
7 files changed, 324 insertions, 277 deletions
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 2cf9cc7aa10..a20dc8a3c94 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -1,6 +1,10 @@
#
# Timer subsystem related configuration options
#
+
+# 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.
config TICK_ONESHOT
bool
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 8a46f5d6450..8a538c55fc7 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -96,6 +96,11 @@ static int alarmtimer_rtc_add_device(struct device *dev,
return 0;
}
+static inline void alarmtimer_rtc_timer_init(void)
+{
+ rtc_timer_init(&rtctimer, NULL, NULL);
+}
+
static struct class_interface alarmtimer_rtc_interface = {
.add_dev = &alarmtimer_rtc_add_device,
};
@@ -117,6 +122,7 @@ static inline struct rtc_device *alarmtimer_get_rtcdev(void)
#define rtcdev (NULL)
static inline int alarmtimer_rtc_interface_setup(void) { return 0; }
static inline void alarmtimer_rtc_interface_remove(void) { }
+static inline void alarmtimer_rtc_timer_init(void) { }
#endif
/**
@@ -783,6 +789,8 @@ static int __init alarmtimer_init(void)
.nsleep = alarm_timer_nsleep,
};
+ alarmtimer_rtc_timer_init();
+
posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock);
posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock);
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index a45ca167ab2..c9583382141 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -500,7 +500,7 @@ static u32 clocksource_max_adjustment(struct clocksource *cs)
{
u64 ret;
/*
- * We won't try to correct for more then 11% adjustments (110,000 ppm),
+ * We won't try to correct for more than 11% adjustments (110,000 ppm),
*/
ret = (u64)cs->mult * 11;
do_div(ret,100);
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 4b85a7a7252..f03fd83b170 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -22,17 +22,18 @@
* NTP timekeeping variables:
*/
+DEFINE_SPINLOCK(ntp_lock);
+
+
/* USER_HZ period (usecs): */
unsigned long tick_usec = TICK_USEC;
/* ACTHZ period (nsecs): */
unsigned long tick_nsec;
-u64 tick_length;
+static u64 tick_length;
static u64 tick_length_base;
-static struct hrtimer leap_timer;
-
#define MAX_TICKADJ 500LL /* usecs */
#define MAX_TICKADJ_SCALED \
(((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
@@ -49,7 +50,7 @@ static struct hrtimer leap_timer;
static int time_state = TIME_OK;
/* clock status bits: */
-int time_status = STA_UNSYNC;
+static int time_status = STA_UNSYNC;
/* TAI offset (secs): */
static long time_tai;
@@ -133,7 +134,7 @@ static inline void pps_reset_freq_interval(void)
/**
* pps_clear - Clears the PPS state variables
*
- * Must be called while holding a write on the xtime_lock
+ * Must be called while holding a write on the ntp_lock
*/
static inline void pps_clear(void)
{
@@ -149,7 +150,7 @@ static inline void pps_clear(void)
* the last PPS signal. When it reaches 0, indicate that PPS signal is
* missing.
*
- * Must be called while holding a write on the xtime_lock
+ * Must be called while holding a write on the ntp_lock
*/
static inline void pps_dec_valid(void)
{
@@ -233,6 +234,17 @@ static inline void pps_fill_timex(struct timex *txc)
#endif /* CONFIG_NTP_PPS */
+
+/**
+ * ntp_synced - Returns 1 if the NTP status is not UNSYNC
+ *
+ */
+static inline int ntp_synced(void)
+{
+ return !(time_status & STA_UNSYNC);
+}
+
+
/*
* NTP methods:
*/
@@ -330,11 +342,13 @@ static void ntp_update_offset(long offset)
/**
* ntp_clear - Clears the NTP state variables
- *
- * Must be called while holding a write on the xtime_lock
*/
void ntp_clear(void)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ntp_lock, flags);
+
time_adjust = 0; /* stop active adjtime() */
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
@@ -347,63 +361,81 @@ void ntp_clear(void)
/* Clear PPS state variables */
pps_clear();
+ spin_unlock_irqrestore(&ntp_lock, flags);
+
+}
+
+
+u64 ntp_tick_length(void)
+{
+ unsigned long flags;
+ s64 ret;
+
+ spin_lock_irqsave(&ntp_lock, flags);
+ ret = tick_length;
+ spin_unlock_irqrestore(&ntp_lock, flags);
+ return ret;
}
+
/*
- * Leap second processing. If in leap-insert state at the end of the
- * day, the system clock is set back one second; if in leap-delete
- * state, the system clock is set ahead one second.
+ * this routine handles the overflow of the microsecond field
+ *
+ * The tricky bits of code to handle the accurate clock support
+ * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
+ * They were originally developed for SUN and DEC kernels.
+ * All the kudos should go to Dave for this stuff.
+ *
+ * Also handles leap second processing, and returns leap offset
*/
-static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
+int second_overflow(unsigned long secs)
{
- enum hrtimer_restart res = HRTIMER_NORESTART;
+ s64 delta;
+ int leap = 0;
+ unsigned long flags;
- write_seqlock(&xtime_lock);
+ spin_lock_irqsave(&ntp_lock, flags);
+ /*
+ * Leap second processing. If in leap-insert state at the end of the
+ * day, the system clock is set back one second; if in leap-delete
+ * state, the system clock is set ahead one second.
+ */
switch (time_state) {
case TIME_OK:
+ if (time_status & STA_INS)
+ time_state = TIME_INS;
+ else if (time_status & STA_DEL)
+ time_state = TIME_DEL;
break;
case TIME_INS:
- timekeeping_leap_insert(-1);
- time_state = TIME_OOP;
- printk(KERN_NOTICE
- "Clock: inserting leap second 23:59:60 UTC\n");
- hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC);
- res = HRTIMER_RESTART;
+ if (secs % 86400 == 0) {
+ leap = -1;
+ time_state = TIME_OOP;
+ printk(KERN_NOTICE
+ "Clock: inserting leap second 23:59:60 UTC\n");
+ }
break;
case TIME_DEL:
- timekeeping_leap_insert(1);
- time_tai--;
- time_state = TIME_WAIT;
- printk(KERN_NOTICE
- "Clock: deleting leap second 23:59:59 UTC\n");
+ 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");
+ }
break;
case TIME_OOP:
time_tai++;
time_state = TIME_WAIT;
- /* fall through */
+ break;
+
case TIME_WAIT:
if (!(time_status & (STA_INS | STA_DEL)))
time_state = TIME_OK;
break;
}
- write_sequnlock(&xtime_lock);
-
- return res;
-}
-
-/*
- * this routine handles the overflow of the microsecond field
- *
- * The tricky bits of code to handle the accurate clock support
- * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
- * They were originally developed for SUN and DEC kernels.
- * All the kudos should go to Dave for this stuff.
- */
-void second_overflow(void)
-{
- s64 delta;
/* Bump the maxerror field */
time_maxerror += MAXFREQ / NSEC_PER_USEC;
@@ -423,30 +455,34 @@ void second_overflow(void)
pps_dec_valid();
if (!time_adjust)
- return;
+ goto out;
if (time_adjust > MAX_TICKADJ) {
time_adjust -= MAX_TICKADJ;
tick_length += MAX_TICKADJ_SCALED;
- return;
+ goto out;
}
if (time_adjust < -MAX_TICKADJ) {
time_adjust += MAX_TICKADJ;
tick_length -= MAX_TICKADJ_SCALED;
- return;
+ goto out;
}
tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ)
<< NTP_SCALE_SHIFT;
time_adjust = 0;
+
+
+
+out:
+ spin_unlock_irqrestore(&ntp_lock, flags);
+
+ return leap;
}
#ifdef CONFIG_GENERIC_CMOS_UPDATE
-/* Disable the cmos update - used by virtualization and embedded */
-int no_sync_cmos_clock __read_mostly;
-
static void sync_cmos_clock(struct work_struct *work);
static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock);
@@ -493,35 +529,13 @@ static void sync_cmos_clock(struct work_struct *work)
static void notify_cmos_timer(void)
{
- if (!no_sync_cmos_clock)
- schedule_delayed_work(&sync_cmos_work, 0);
+ schedule_delayed_work(&sync_cmos_work, 0);
}
#else
static inline void notify_cmos_timer(void) { }
#endif
-/*
- * Start the leap seconds timer:
- */
-static inline void ntp_start_leap_timer(struct timespec *ts)
-{
- long now = ts->tv_sec;
-
- if (time_status & STA_INS) {
- time_state = TIME_INS;
- now += 86400 - now % 86400;
- hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
-
- return;
- }
-
- if (time_status & STA_DEL) {
- time_state = TIME_DEL;
- now += 86400 - (now + 1) % 86400;
- hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
- }
-}
/*
* Propagate a new txc->status value into the NTP state:
@@ -546,22 +560,6 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts)
time_status &= STA_RONLY;
time_status |= txc->status & ~STA_RONLY;
- switch (time_state) {
- case TIME_OK:
- ntp_start_leap_timer(ts);
- break;
- case TIME_INS:
- case TIME_DEL:
- time_state = TIME_OK;
- ntp_start_leap_timer(ts);
- case TIME_WAIT:
- if (!(time_status & (STA_INS | STA_DEL)))
- time_state = TIME_OK;
- break;
- case TIME_OOP:
- hrtimer_restart(&leap_timer);
- break;
- }
}
/*
* Called with the xtime lock held, so we can access and modify
@@ -643,9 +641,6 @@ int do_adjtimex(struct timex *txc)
(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 (txc->modes & ADJ_SETOFFSET) {
@@ -663,7 +658,7 @@ int do_adjtimex(struct timex *txc)
getnstimeofday(&ts);
- write_seqlock_irq(&xtime_lock);
+ spin_lock_irq(&ntp_lock);
if (txc->modes & ADJ_ADJTIME) {
long save_adjust = time_adjust;
@@ -705,7 +700,7 @@ int do_adjtimex(struct timex *txc)
/* fill PPS status fields */
pps_fill_timex(txc);
- write_sequnlock_irq(&xtime_lock);
+ spin_unlock_irq(&ntp_lock);
txc->time.tv_sec = ts.tv_sec;
txc->time.tv_usec = ts.tv_nsec;
@@ -903,7 +898,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
pts_norm = pps_normalize_ts(*phase_ts);
- write_seqlock_irqsave(&xtime_lock, flags);
+ 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);
@@ -916,7 +911,7 @@ 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;
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ spin_unlock_irqrestore(&ntp_lock, flags);
return;
}
@@ -931,7 +926,7 @@ 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;
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ spin_unlock_irqrestore(&ntp_lock, flags);
pr_err("hardpps: PPSJITTER: bad pulse\n");
return;
}
@@ -948,7 +943,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
hardpps_update_phase(pts_norm.nsec);
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ spin_unlock_irqrestore(&ntp_lock, flags);
}
EXPORT_SYMBOL(hardpps);
@@ -967,6 +962,4 @@ __setup("ntp_tick_adj=", ntp_tick_adj_setup);
void __init ntp_init(void)
{
ntp_clear();
- hrtimer_init(&leap_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
- leap_timer.function = ntp_leap_second;
}
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index fd4a7b1625a..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);
@@ -580,6 +584,7 @@ void tick_broadcast_switch_to_oneshot(void)
bc = tick_broadcast_device.evtdev;
if (bc)
tick_broadcast_setup_oneshot(bc);
+
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 4aa1d7b7cfd..6a3a5b9ff56 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -182,11 +182,7 @@ static void tick_nohz_stop_idle(int cpu, ktime_t now)
static ktime_t tick_nohz_start_idle(int cpu, struct tick_sched *ts)
{
- ktime_t now;
-
- now = ktime_get();
-
- update_ts_time_stats(cpu, ts, now, NULL);
+ ktime_t now = ktime_get();
ts->idle_entrytime = now;
ts->idle_active = 1;
@@ -562,20 +558,21 @@ void tick_nohz_idle_exit(void)
local_irq_disable();
- if (ts->idle_active || (ts->inidle && ts->tick_stopped))
+ WARN_ON_ONCE(!ts->inidle);
+
+ ts->inidle = 0;
+
+ if (ts->idle_active || ts->tick_stopped)
now = ktime_get();
if (ts->idle_active)
tick_nohz_stop_idle(cpu, now);
- if (!ts->inidle || !ts->tick_stopped) {
- ts->inidle = 0;
+ if (!ts->tick_stopped) {
local_irq_enable();
return;
}
- ts->inidle = 0;
-
/* Update jiffies first */
select_nohz_load_balancer(0);
tick_do_update_jiffies64(now);
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 9cffcab0565..d66b21308f7 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -25,6 +25,8 @@
struct timekeeper {
/* Current clocksource used for timekeeping. */
struct clocksource *clock;
+ /* NTP adjusted clock multiplier */
+ u32 mult;
/* The shift value of the current clocksource. */
int shift;
@@ -45,12 +47,47 @@ struct timekeeper {
/* Shift conversion between clock shifted nano seconds and
* ntp shifted nano seconds. */
int ntp_error_shift;
- /* NTP adjusted clock multiplier */
- u32 mult;
+
+ /* The current time */
+ struct timespec xtime;
+ /*
+ * wall_to_monotonic is what we need to add to xtime (or xtime corrected
+ * for sub jiffie times) to get to monotonic time. Monotonic is pegged
+ * at zero at system boot time, so wall_to_monotonic will be negative,
+ * however, we will ALWAYS keep the tv_nsec part positive so we can use
+ * the usual normalization.
+ *
+ * wall_to_monotonic is moved after resume from suspend for the
+ * monotonic time not to jump. We need to add total_sleep_time to
+ * wall_to_monotonic to get the real boot based time offset.
+ *
+ * - wall_to_monotonic is no longer the boot time, getboottime must be
+ * used instead.
+ */
+ struct timespec wall_to_monotonic;
+ /* time spent in suspend */
+ struct timespec total_sleep_time;
+ /* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
+ struct timespec raw_time;
+
+ /* Seqlock for all timekeeper values */
+ seqlock_t lock;
};
static struct timekeeper timekeeper;
+/*
+ * This read-write spinlock protects us from races in SMP while
+ * playing with xtime.
+ */
+__cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
+
+
+/* flag for if timekeeping is suspended */
+int __read_mostly timekeeping_suspended;
+
+
+
/**
* timekeeper_setup_internals - Set up internals to use clocksource clock.
*
@@ -135,49 +172,18 @@ static inline s64 timekeeping_get_ns_raw(void)
return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
}
-/*
- * This read-write spinlock protects us from races in SMP while
- * playing with xtime.
- */
-__cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
-
-
-/*
- * The current time
- * wall_to_monotonic is what we need to add to xtime (or xtime corrected
- * for sub jiffie times) to get to monotonic time. Monotonic is pegged
- * at zero at system boot time, so wall_to_monotonic will be negative,
- * however, we will ALWAYS keep the tv_nsec part positive so we can use
- * the usual normalization.
- *
- * wall_to_monotonic is moved after resume from suspend for the monotonic
- * time not to jump. We need to add total_sleep_time to wall_to_monotonic
- * to get the real boot based time offset.
- *
- * - wall_to_monotonic is no longer the boot time, getboottime must be
- * used instead.
- */
-static struct timespec xtime __attribute__ ((aligned (16)));
-static struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
-static struct timespec total_sleep_time;
-
-/*
- * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
- */
-static struct timespec raw_time;
-
-/* flag for if timekeeping is suspended */
-int __read_mostly timekeeping_suspended;
-
-/* must hold xtime_lock */
-void timekeeping_leap_insert(int leapsecond)
+/* must hold write on timekeeper.lock */
+static void timekeeping_update(bool clearntp)
{
- xtime.tv_sec += leapsecond;
- wall_to_monotonic.tv_sec -= leapsecond;
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ if (clearntp) {
+ timekeeper.ntp_error = 0;
+ ntp_clear();
+ }
+ update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
+ timekeeper.clock, timekeeper.mult);
}
+
/**
* timekeeping_forward_now - update clock to the current time
*
@@ -202,10 +208,10 @@ static void timekeeping_forward_now(void)
/* If arch requires, add in gettimeoffset() */
nsec += arch_gettimeoffset();
- timespec_add_ns(&xtime, nsec);
+ timespec_add_ns(&timekeeper.xtime, nsec);
nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
- timespec_add_ns(&raw_time, nsec);
+ timespec_add_ns(&timekeeper.raw_time, nsec);
}
/**
@@ -222,15 +228,15 @@ void getnstimeofday(struct timespec *ts)
WARN_ON(timekeeping_suspended);
do {
- seq = read_seqbegin(&xtime_lock);
+ seq = read_seqbegin(&timekeeper.lock);
- *ts = xtime;
+ *ts = timekeeper.xtime;
nsecs = timekeeping_get_ns();
/* If arch requires, add in gettimeoffset() */
nsecs += arch_gettimeoffset();
- } while (read_seqretry(&xtime_lock, seq));
+ } while (read_seqretry(&timekeeper.lock, seq));
timespec_add_ns(ts, nsecs);
}
@@ -245,14 +251,16 @@ ktime_t ktime_get(void)
WARN_ON(timekeeping_suspended);
do {
- seq = read_seqbegin(&xtime_lock);
- secs = xtime.tv_sec + wall_to_monotonic.tv_sec;
- nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec;
+ seq = read_seqbegin(&timekeeper.lock);
+ secs = timekeeper.xtime.tv_sec +
+ timekeeper.wall_to_monotonic.tv_sec;
+ nsecs = timekeeper.xtime.tv_nsec +
+ timekeeper.wall_to_monotonic.tv_nsec;
nsecs += timekeeping_get_ns();
/* If arch requires, add in gettimeoffset() */
nsecs += arch_gettimeoffset();
- } while (read_seqretry(&xtime_lock, seq));
+ } while (read_seqretry(&timekeeper.lock, seq));
/*
* Use ktime_set/ktime_add_ns to create a proper ktime on
* 32-bit architectures without CONFIG_KTIME_SCALAR.
@@ -278,14 +286,14 @@ void ktime_get_ts(struct timespec *ts)
WARN_ON(timekeeping_suspended);
do {
- seq = read_seqbegin(&xtime_lock);
- *ts = xtime;
- tomono = wall_to_monotonic;
+ seq = read_seqbegin(&timekeeper.lock);
+ *ts = timekeeper.xtime;
+ tomono = timekeeper.wall_to_monotonic;
nsecs = timekeeping_get_ns();
/* If arch requires, add in gettimeoffset() */
nsecs += arch_gettimeoffset();
- } while (read_seqretry(&xtime_lock, seq));
+ } while (read_seqretry(&timekeeper.lock, seq));
set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
ts->tv_nsec + tomono.tv_nsec + nsecs);
@@ -313,10 +321,10 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real)
do {
u32 arch_offset;
- seq = read_seqbegin(&xtime_lock);
+ seq = read_seqbegin(&timekeeper.lock);
- *ts_raw = raw_time;
- *ts_real = xtime;
+ *ts_raw = timekeeper.raw_time;
+ *ts_real = timekeeper.xtime;
nsecs_raw = timekeeping_get_ns_raw();
nsecs_real = timekeeping_get_ns();
@@ -326,7 +334,7 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real)
nsecs_raw += arch_offset;
nsecs_real += arch_offset;
- } while (read_seqretry(&xtime_lock, seq));
+ } while (read_seqretry(&timekeeper.lock, seq));
timespec_add_ns(ts_raw, nsecs_raw);
timespec_add_ns(ts_real, nsecs_real);
@@ -365,23 +373,19 @@ int do_settimeofday(const struct timespec *tv)
if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
- write_seqlock_irqsave(&xtime_lock, flags);
+ write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_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);
+ ts_delta.tv_sec = tv->tv_sec - timekeeper.xtime.tv_sec;
+ ts_delta.tv_nsec = tv->tv_nsec - timekeeper.xtime.tv_nsec;
+ timekeeper.wall_to_monotonic =
+ timespec_sub(timekeeper.wall_to_monotonic, ts_delta);
- xtime = *tv;
-
- timekeeper.ntp_error = 0;
- ntp_clear();
+ timekeeper.xtime = *tv;
+ timekeeping_update(true);
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
-
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@@ -405,20 +409,17 @@ int timekeeping_inject_offset(struct timespec *ts)
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
- write_seqlock_irqsave(&xtime_lock, flags);
+ write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_forward_now();
- xtime = timespec_add(xtime, *ts);
- wall_to_monotonic = timespec_sub(wall_to_monotonic, *ts);
-
- timekeeper.ntp_error = 0;
- ntp_clear();
+ timekeeper.xtime = timespec_add(timekeeper.xtime, *ts);
+ timekeeper.wall_to_monotonic =
+ timespec_sub(timekeeper.wall_to_monotonic, *ts);
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ timekeeping_update(true);
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@@ -435,9 +436,12 @@ EXPORT_SYMBOL(timekeeping_inject_offset);
static int change_clocksource(void *data)
{
struct clocksource *new, *old;
+ unsigned long flags;
new = (struct clocksource *) data;
+ write_seqlock_irqsave(&timekeeper.lock, flags);
+
timekeeping_forward_now();
if (!new->enable || new->enable(new) == 0) {
old = timekeeper.clock;
@@ -445,6 +449,10 @@ static int change_clocksource(void *data)
if (old->disable)
old->disable(old);
}
+ timekeeping_update(true);
+
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
+
return 0;
}
@@ -490,11 +498,11 @@ void getrawmonotonic(struct timespec *ts)
s64 nsecs;
do {
- seq = read_seqbegin(&xtime_lock);
+ seq = read_seqbegin(&timekeeper.lock);
nsecs = timekeeping_get_ns_raw();
- *ts = raw_time;
+ *ts = timekeeper.raw_time;
- } while (read_seqretry(&xtime_lock, seq));
+ } while (read_seqretry(&timekeeper.lock, seq));
timespec_add_ns(ts, nsecs);
}
@@ -510,24 +518,30 @@ int timekeeping_valid_for_hres(void)
int ret;
do {
- seq = read_seqbegin(&xtime_lock);
+ seq = read_seqbegin(&timekeeper.lock);
ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
- } while (read_seqretry(&xtime_lock, seq));
+ } while (read_seqretry(&timekeeper.lock, seq));
return ret;
}
/**
* timekeeping_max_deferment - Returns max time the clocksource can be deferred
- *
- * Caller must observe xtime_lock via read_seqbegin/read_seqretry to
- * ensure that the clocksource does not change!
*/
u64 timekeeping_max_deferment(void)
{
- return timekeeper.clock->max_idle_ns;
+ unsigned long seq;
+ u64 ret;
+ do {
+ seq = read_seqbegin(&timekeeper.lock);
+
+ ret = timekeeper.clock->max_idle_ns;
+
+ } while (read_seqretry(&timekeeper.lock, seq));
+
+ return ret;
}
/**
@@ -572,28 +586,29 @@ void __init timekeeping_init(void)
read_persistent_clock(&now);
read_boot_clock(&boot);
- write_seqlock_irqsave(&xtime_lock, flags);
+ seqlock_init(&timekeeper.lock);
ntp_init();
+ write_seqlock_irqsave(&timekeeper.lock, flags);
clock = clocksource_default_clock();
if (clock->enable)
clock->enable(clock);
timekeeper_setup_internals(clock);
- xtime.tv_sec = now.tv_sec;
- xtime.tv_nsec = now.tv_nsec;
- raw_time.tv_sec = 0;
- raw_time.tv_nsec = 0;
+ timekeeper.xtime.tv_sec = now.tv_sec;
+ timekeeper.xtime.tv_nsec = now.tv_nsec;
+ timekeeper.raw_time.tv_sec = 0;
+ timekeeper.raw_time.tv_nsec = 0;
if (boot.tv_sec == 0 && boot.tv_nsec == 0) {
- boot.tv_sec = xtime.tv_sec;
- boot.tv_nsec = xtime.tv_nsec;
+ boot.tv_sec = timekeeper.xtime.tv_sec;
+ boot.tv_nsec = timekeeper.xtime.tv_nsec;
}
- set_normalized_timespec(&wall_to_monotonic,
+ set_normalized_timespec(&timekeeper.wall_to_monotonic,
-boot.tv_sec, -boot.tv_nsec);
- total_sleep_time.tv_sec = 0;
- total_sleep_time.tv_nsec = 0;
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ timekeeper.total_sleep_time.tv_sec = 0;
+ timekeeper.total_sleep_time.tv_nsec = 0;
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
}
/* time in seconds when suspend began */
@@ -614,9 +629,11 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
return;
}
- xtime = timespec_add(xtime, *delta);
- wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta);
- total_sleep_time = timespec_add(total_sleep_time, *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);
}
@@ -640,17 +657,15 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
if (!(ts.tv_sec == 0 && ts.tv_nsec == 0))
return;
- write_seqlock_irqsave(&xtime_lock, flags);
+ write_seqlock_irqsave(&timekeeper.lock, flags);
+
timekeeping_forward_now();
__timekeeping_inject_sleeptime(delta);
- timekeeper.ntp_error = 0;
- ntp_clear();
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ timekeeping_update(true);
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@@ -673,7 +688,7 @@ static void timekeeping_resume(void)
clocksource_resume();
- write_seqlock_irqsave(&xtime_lock, flags);
+ write_seqlock_irqsave(&timekeeper.lock, flags);
if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
ts = timespec_sub(ts, timekeeping_suspend_time);
@@ -683,7 +698,7 @@ static void timekeeping_resume(void)
timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
timekeeper.ntp_error = 0;
timekeeping_suspended = 0;
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
touch_softlockup_watchdog();
@@ -701,7 +716,7 @@ static int timekeeping_suspend(void)
read_persistent_clock(&timekeeping_suspend_time);
- write_seqlock_irqsave(&xtime_lock, flags);
+ write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_forward_now();
timekeeping_suspended = 1;
@@ -711,7 +726,7 @@ static int timekeeping_suspend(void)
* try to compensate so the difference in system time
* and persistent_clock time stays close to constant.
*/
- delta = timespec_sub(xtime, timekeeping_suspend_time);
+ delta = timespec_sub(timekeeper.xtime, timekeeping_suspend_time);
delta_delta = timespec_sub(delta, old_delta);
if (abs(delta_delta.tv_sec) >= 2) {
/*
@@ -724,7 +739,7 @@ static int timekeeping_suspend(void)
timekeeping_suspend_time =
timespec_add(timekeeping_suspend_time, delta_delta);
}
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
clocksource_suspend();
@@ -775,7 +790,7 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
* Now calculate the error in (1 << look_ahead) ticks, but first
* remove the single look ahead already included in the error.
*/
- tick_error = tick_length >> (timekeeper.ntp_error_shift + 1);
+ tick_error = ntp_tick_length() >> (timekeeper.ntp_error_shift + 1);
tick_error -= timekeeper.xtime_interval >> 1;
error = ((error - tick_error) >> look_ahead) + tick_error;
@@ -807,7 +822,7 @@ static void timekeeping_adjust(s64 offset)
int adj;
/*
- * The point of this is to check if the error is greater then half
+ * The point of this is to check if the error is greater than half
* an interval.
*
* First we shift it down from NTP_SHIFT to clocksource->shifted nsecs.
@@ -815,7 +830,7 @@ static void timekeeping_adjust(s64 offset)
* Note we subtract one in the shift, so that error is really error*2.
* This "saves" dividing(shifting) interval twice, but keeps the
* (error > interval) comparison as still measuring if error is
- * larger then half an interval.
+ * larger than half an interval.
*
* Note: It does not "save" on aggravation when reading the code.
*/
@@ -823,7 +838,7 @@ static void timekeeping_adjust(s64 offset)
if (error > interval) {
/*
* We now divide error by 4(via shift), which checks if
- * the error is greater then twice the interval.
+ * the error is greater than twice the interval.
* If it is greater, we need a bigadjust, if its smaller,
* we can adjust by 1.
*/
@@ -854,6 +869,15 @@ static void timekeeping_adjust(s64 offset)
} else /* No adjustment needed */
return;
+ if (unlikely(timekeeper.clock->maxadj &&
+ (timekeeper.mult + adj >
+ timekeeper.clock->mult + timekeeper.clock->maxadj))) {
+ printk_once(KERN_WARNING
+ "Adjusting %s more than 11%% (%ld vs %ld)\n",
+ timekeeper.clock->name, (long)timekeeper.mult + adj,
+ (long)timekeeper.clock->mult +
+ timekeeper.clock->maxadj);
+ }
/*
* So the following can be confusing.
*
@@ -925,7 +949,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
u64 raw_nsecs;
- /* If the offset is smaller then a shifted interval, do nothing */
+ /* If the offset is smaller than a shifted interval, do nothing */
if (offset < timekeeper.cycle_interval<<shift)
return offset;
@@ -935,23 +959,25 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;
while (timekeeper.xtime_nsec >= nsecps) {
+ int leap;
timekeeper.xtime_nsec -= nsecps;
- xtime.tv_sec++;
- second_overflow();
+ timekeeper.xtime.tv_sec++;
+ leap = second_overflow(timekeeper.xtime.tv_sec);
+ timekeeper.xtime.tv_sec += leap;
}
/* Accumulate raw time */
raw_nsecs = timekeeper.raw_interval << shift;
- raw_nsecs += raw_time.tv_nsec;
+ raw_nsecs += timekeeper.raw_time.tv_nsec;
if (raw_nsecs >= NSEC_PER_SEC) {
u64 raw_secs = raw_nsecs;
raw_nsecs = do_div(raw_secs, NSEC_PER_SEC);
- raw_time.tv_sec += raw_secs;
+ timekeeper.raw_time.tv_sec += raw_secs;
}
- raw_time.tv_nsec = raw_nsecs;
+ timekeeper.raw_time.tv_nsec = raw_nsecs;
/* Accumulate error between NTP and clock interval */
- timekeeper.ntp_error += tick_length << shift;
+ timekeeper.ntp_error += ntp_tick_length() << shift;
timekeeper.ntp_error -=
(timekeeper.xtime_interval + timekeeper.xtime_remainder) <<
(timekeeper.ntp_error_shift + shift);
@@ -963,17 +989,19 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
/**
* update_wall_time - Uses the current clocksource to increment the wall time
*
- * Called from the timer interrupt, must hold a write on xtime_lock.
*/
static void update_wall_time(void)
{
struct clocksource *clock;
cycle_t offset;
int shift = 0, maxshift;
+ unsigned long flags;
+
+ write_seqlock_irqsave(&timekeeper.lock, flags);
/* Make sure we're fully resumed: */
if (unlikely(timekeeping_suspended))
- return;
+ goto out;
clock = timekeeper.clock;
@@ -982,20 +1010,21 @@ static void update_wall_time(void)
#else
offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
#endif
- timekeeper.xtime_nsec = (s64)xtime.tv_nsec << timekeeper.shift;
+ timekeeper.xtime_nsec = (s64)timekeeper.xtime.tv_nsec <<
+ timekeeper.shift;
/*
* With NO_HZ we may have to accumulate many cycle_intervals
* (think "ticks") worth of time at once. To do this efficiently,
* we calculate the largest doubling multiple of cycle_intervals
- * that is smaller then the offset. We then accumulate that
+ * that is smaller than the offset. We then accumulate that
* chunk in one go, and then try to consume the next smaller
* doubled multiple.
*/
shift = ilog2(offset) - ilog2(timekeeper.cycle_interval);
shift = max(0, shift);
- /* Bound shift to one less then what overflows tick_length */
- maxshift = (8*sizeof(tick_length) - (ilog2(tick_length)+1)) - 1;
+ /* Bound shift to one less than what overflows tick_length */
+ maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
shift = min(shift, maxshift);
while (offset >= timekeeper.cycle_interval) {
offset = logarithmic_accumulation(offset, shift);
@@ -1033,24 +1062,30 @@ static void update_wall_time(void)
* Store full nanoseconds into xtime after rounding it up and
* add the remainder to the error difference.
*/
- xtime.tv_nsec = ((s64) timekeeper.xtime_nsec >> timekeeper.shift) + 1;
- timekeeper.xtime_nsec -= (s64) xtime.tv_nsec << timekeeper.shift;
+ timekeeper.xtime.tv_nsec = ((s64)timekeeper.xtime_nsec >>
+ timekeeper.shift) + 1;
+ timekeeper.xtime_nsec -= (s64)timekeeper.xtime.tv_nsec <<
+ timekeeper.shift;
timekeeper.ntp_error += timekeeper.xtime_nsec <<
timekeeper.ntp_error_shift;
/*
* Finally, make sure that after the rounding
- * xtime.tv_nsec isn't larger then NSEC_PER_SEC
+ * xtime.tv_nsec isn't larger than NSEC_PER_SEC
*/
- if (unlikely(xtime.tv_nsec >= NSEC_PER_SEC)) {
- xtime.tv_nsec -= NSEC_PER_SEC;
- xtime.tv_sec++;
- second_overflow();
+ if (unlikely(timekeeper.xtime.tv_nsec >= NSEC_PER_SEC)) {
+ int leap;
+ timekeeper.xtime.tv_nsec -= NSEC_PER_SEC;
+ timekeeper.xtime.tv_sec++;
+ leap = second_overflow(timekeeper.xtime.tv_sec);
+ timekeeper.xtime.tv_sec += leap;
}
- /* check to see if there is a new clocksource to use */
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ timekeeping_update(false);
+
+out:
+ write_sequnlock_irqrestore(&timekeeper.lock, flags);
+
}
/**
@@ -1067,8 +1102,10 @@ static void update_wall_time(void)
void getboottime(struct timespec *ts)
{
struct timespec boottime = {
- .tv_sec = wall_to_monotonic.tv_sec + total_sleep_time.tv_sec,
- .tv_nsec = wall_to_monotonic.tv_nsec + total_sleep_time.tv_nsec
+ .tv_sec = timekeeper.wall_to_monotonic.tv_sec +
+ timekeeper.total_sleep_time.tv_sec,
+ .tv_nsec = timekeeper.wall_to_monotonic.tv_nsec +
+ timekeeper.total_sleep_time.tv_nsec
};
set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec);
@@ -1094,13 +1131,13 @@ void get_monotonic_boottime(struct timespec *ts)
WARN_ON(timekeeping_suspended);
do {
- seq = read_seqbegin(&xtime_lock);
- *ts = xtime;
- tomono = wall_to_monotonic;
- sleep = total_sleep_time;
+ seq = read_seqbegin(&timekeeper.lock);
+ *ts = timekeeper.xtime;
+ tomono = timekeeper.wall_to_monotonic;
+ sleep = timekeeper.total_sleep_time;
nsecs = timekeeping_get_ns();
- } while (read_seqretry(&xtime_lock, seq));
+ } while (read_seqretry(&timekeeper.lock, seq));
set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec,
ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec + nsecs);
@@ -1130,19 +1167,19 @@ EXPORT_SYMBOL_GPL(ktime_get_boottime);
*/
void monotonic_to_bootbased(struct timespec *ts)
{
- *ts = timespec_add(*ts, total_sleep_time);
+ *ts = timespec_add(*ts, timekeeper.total_sleep_time);
}
EXPORT_SYMBOL_GPL(monotonic_to_bootbased);
unsigned long get_seconds(void)
{
- return xtime.tv_sec;
+ return timekeeper.xtime.tv_sec;
}
EXPORT_SYMBOL(get_seconds);
struct timespec __current_kernel_time(void)
{
- return xtime;
+ return timekeeper.xtime;
}
struct timespec current_kernel_time(void)
@@ -1151,10 +1188,10 @@ struct timespec current_kernel_time(void)
unsigned long seq;
do {
- seq = read_seqbegin(&xtime_lock);
+ seq = read_seqbegin(&timekeeper.lock);
- now = xtime;
- } while (read_seqretry(&xtime_lock, seq));
+ now = timekeeper.xtime;
+ } while (read_seqretry(&timekeeper.lock, seq));
return now;
}
@@ -1166,11 +1203,11 @@ struct timespec get_monotonic_coarse(void)
unsigned long seq;
do {
- seq = read_seqbegin(&xtime_lock);
+ seq = read_seqbegin(&timekeeper.lock);
- now = xtime;
- mono = wall_to_monotonic;
- } while (read_seqretry(&xtime_lock, seq));
+ now = timekeeper.xtime;
+ mono = timekeeper.wall_to_monotonic;
+ } while (read_seqretry(&timekeeper.lock, seq));
set_normalized_timespec(&now, now.tv_sec + mono.tv_sec,
now.tv_nsec + mono.tv_nsec);
@@ -1202,11 +1239,11 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
unsigned long seq;
do {
- seq = read_seqbegin(&xtime_lock);
- *xtim = xtime;
- *wtom = wall_to_monotonic;
- *sleep = total_sleep_time;
- } while (read_seqretry(&xtime_lock, seq));
+ seq = read_seqbegin(&timekeeper.lock);
+ *xtim = timekeeper.xtime;
+ *wtom = timekeeper.wall_to_monotonic;
+ *sleep = timekeeper.total_sleep_time;
+ } while (read_seqretry(&timekeeper.lock, seq));
}
/**
@@ -1218,11 +1255,14 @@ ktime_t ktime_get_monotonic_offset(void)
struct timespec wtom;
do {
- seq = read_seqbegin(&xtime_lock);
- wtom = wall_to_monotonic;
- } while (read_seqretry(&xtime_lock, seq));
+ seq = read_seqbegin(&timekeeper.lock);
+ wtom = timekeeper.wall_to_monotonic;
+ } while (read_seqretry(&timekeeper.lock, seq));
+
return timespec_to_ktime(wtom);
}
+EXPORT_SYMBOL_GPL(ktime_get_monotonic_offset);
+
/**
* xtime_update() - advances the timekeeping infrastructure