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authorAnton Arapov <anton@redhat.com>2012-10-29 11:15:37 +0100
committerAnton Arapov <anton@redhat.com>2012-10-29 11:15:37 +0100
commit7d558cd9c7b18e4b16953265aa0da45e63f3b968 (patch)
tree7135d5a810768c9c619346282ee9cfdf1765e225 /kernel/time
parent985ef6b2108ed28ffd5f6630e1e0fce2e2a775f2 (diff)
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fedora kernel: cd394142aac30b5c751f25b517572e2448695641v3.6.3-2f17
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'kernel/time')
-rw-r--r--kernel/time/jiffies.c2
-rw-r--r--kernel/time/ntp.c2
-rw-r--r--kernel/time/tick-sched.c195
-rw-r--r--kernel/time/timekeeping.c798
-rw-r--r--kernel/time/timer_list.c4
5 files changed, 565 insertions, 436 deletions
diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c
index a470154e040..46da0537c10 100644
--- a/kernel/time/jiffies.c
+++ b/kernel/time/jiffies.c
@@ -37,7 +37,7 @@
* requested HZ value. It is also not recommended
* for "tick-less" systems.
*/
-#define NSEC_PER_JIFFY ((u32)((((u64)NSEC_PER_SEC)<<8)/ACTHZ))
+#define NSEC_PER_JIFFY ((u32)((((u64)NSEC_PER_SEC)<<8)/SHIFTED_HZ))
/* Since jiffies uses a simple NSEC_PER_JIFFY multiplier
* conversion, the .shift value could be zero. However
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index b7fbadc5c97..24174b4d669 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -28,7 +28,7 @@ DEFINE_SPINLOCK(ntp_lock);
/* USER_HZ period (usecs): */
unsigned long tick_usec = TICK_USEC;
-/* ACTHZ period (nsecs): */
+/* SHIFTED_HZ period (nsecs): */
unsigned long tick_nsec;
static u64 tick_length;
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 4a08472c3ca..e430b97438d 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -105,7 +105,7 @@ static ktime_t tick_init_jiffy_update(void)
/*
* NO HZ enabled ?
*/
-static int tick_nohz_enabled __read_mostly = 1;
+int tick_nohz_enabled __read_mostly = 1;
/*
* Enable / Disable tickless mode
@@ -271,50 +271,15 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time)
}
EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us);
-static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
+static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
+ ktime_t now, int cpu)
{
unsigned long seq, last_jiffies, next_jiffies, delta_jiffies;
+ ktime_t last_update, expires, ret = { .tv64 = 0 };
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;
- int cpu;
-
- cpu = smp_processor_id();
- ts = &per_cpu(tick_cpu_sched, cpu);
-
- now = tick_nohz_start_idle(cpu, ts);
-
- /*
- * If this cpu is offline and it is the one which updates
- * jiffies, then give up the assignment and let it be taken by
- * the cpu which runs the tick timer next. If we don't drop
- * this here the jiffies might be stale and do_timer() never
- * invoked.
- */
- if (unlikely(!cpu_online(cpu))) {
- if (cpu == tick_do_timer_cpu)
- tick_do_timer_cpu = TICK_DO_TIMER_NONE;
- }
-
- if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
- return;
- if (need_resched())
- return;
-
- if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
- static int ratelimit;
-
- if (ratelimit < 10) {
- printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
- (unsigned int) local_softirq_pending());
- ratelimit++;
- }
- return;
- }
-
- ts->idle_calls++;
/* Read jiffies and the time when jiffies were updated last */
do {
seq = read_seqbegin(&xtime_lock);
@@ -397,6 +362,8 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
if (ts->tick_stopped && ktime_equal(expires, dev->next_event))
goto out;
+ ret = expires;
+
/*
* nohz_stop_sched_tick can be called several times before
* the nohz_restart_sched_tick is called. This happens when
@@ -408,16 +375,10 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
select_nohz_load_balancer(1);
calc_load_enter_idle();
- ts->idle_tick = hrtimer_get_expires(&ts->sched_timer);
+ ts->last_tick = hrtimer_get_expires(&ts->sched_timer);
ts->tick_stopped = 1;
- ts->idle_jiffies = last_jiffies;
}
- ts->idle_sleeps++;
-
- /* Mark expires */
- ts->idle_expires = expires;
-
/*
* If the expiration time == KTIME_MAX, then
* in this case we simply stop the tick timer.
@@ -448,6 +409,65 @@ out:
ts->next_jiffies = next_jiffies;
ts->last_jiffies = last_jiffies;
ts->sleep_length = ktime_sub(dev->next_event, now);
+
+ return ret;
+}
+
+static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
+{
+ /*
+ * If this cpu is offline and it is the one which updates
+ * jiffies, then give up the assignment and let it be taken by
+ * the cpu which runs the tick timer next. If we don't drop
+ * this here the jiffies might be stale and do_timer() never
+ * invoked.
+ */
+ if (unlikely(!cpu_online(cpu))) {
+ if (cpu == tick_do_timer_cpu)
+ tick_do_timer_cpu = TICK_DO_TIMER_NONE;
+ }
+
+ if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
+ return false;
+
+ if (need_resched())
+ return false;
+
+ if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
+ static int ratelimit;
+
+ if (ratelimit < 10) {
+ printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
+ (unsigned int) local_softirq_pending());
+ ratelimit++;
+ }
+ return false;
+ }
+
+ return true;
+}
+
+static void __tick_nohz_idle_enter(struct tick_sched *ts)
+{
+ ktime_t now, expires;
+ int cpu = smp_processor_id();
+
+ now = tick_nohz_start_idle(cpu, ts);
+
+ if (can_stop_idle_tick(cpu, ts)) {
+ int was_stopped = ts->tick_stopped;
+
+ ts->idle_calls++;
+
+ expires = tick_nohz_stop_sched_tick(ts, now, cpu);
+ if (expires.tv64 > 0LL) {
+ ts->idle_sleeps++;
+ ts->idle_expires = expires;
+ }
+
+ if (!was_stopped && ts->tick_stopped)
+ ts->idle_jiffies = ts->last_jiffies;
+ }
}
/**
@@ -485,7 +505,7 @@ void tick_nohz_idle_enter(void)
* update of the idle time accounting in tick_nohz_start_idle().
*/
ts->inidle = 1;
- tick_nohz_stop_sched_tick(ts);
+ __tick_nohz_idle_enter(ts);
local_irq_enable();
}
@@ -505,7 +525,7 @@ void tick_nohz_irq_exit(void)
if (!ts->inidle)
return;
- tick_nohz_stop_sched_tick(ts);
+ __tick_nohz_idle_enter(ts);
}
/**
@@ -523,7 +543,7 @@ ktime_t tick_nohz_get_sleep_length(void)
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);
+ hrtimer_set_expires(&ts->sched_timer, ts->last_tick);
while (1) {
/* Forward the time to expire in the future */
@@ -546,6 +566,42 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
}
}
+static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now)
+{
+ /* Update jiffies first */
+ select_nohz_load_balancer(0);
+ tick_do_update_jiffies64(now);
+ update_cpu_load_nohz();
+
+ calc_load_exit_idle();
+ touch_softlockup_watchdog();
+ /*
+ * Cancel the scheduled timer and restore the tick
+ */
+ ts->tick_stopped = 0;
+ ts->idle_exittime = now;
+
+ tick_nohz_restart(ts, now);
+}
+
+static void tick_nohz_account_idle_ticks(struct tick_sched *ts)
+{
+#ifndef CONFIG_VIRT_CPU_ACCOUNTING
+ unsigned long ticks;
+ /*
+ * We stopped the tick in idle. Update process times would miss the
+ * time we slept as update_process_times does only a 1 tick
+ * accounting. Enforce that this is accounted to idle !
+ */
+ ticks = jiffies - ts->idle_jiffies;
+ /*
+ * We might be one off. Do not randomly account a huge number of ticks!
+ */
+ if (ticks && ticks < LONG_MAX)
+ account_idle_ticks(ticks);
+#endif
+}
+
/**
* tick_nohz_idle_exit - restart the idle tick from the idle task
*
@@ -557,9 +613,6 @@ void tick_nohz_idle_exit(void)
{
int cpu = smp_processor_id();
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
-#ifndef CONFIG_VIRT_CPU_ACCOUNTING
- unsigned long ticks;
-#endif
ktime_t now;
local_irq_disable();
@@ -574,40 +627,11 @@ void tick_nohz_idle_exit(void)
if (ts->idle_active)
tick_nohz_stop_idle(cpu, now);
- if (!ts->tick_stopped) {
- local_irq_enable();
- return;
+ if (ts->tick_stopped) {
+ tick_nohz_restart_sched_tick(ts, now);
+ tick_nohz_account_idle_ticks(ts);
}
- /* Update jiffies first */
- select_nohz_load_balancer(0);
- tick_do_update_jiffies64(now);
- update_cpu_load_nohz();
-
-#ifndef CONFIG_VIRT_CPU_ACCOUNTING
- /*
- * We stopped the tick in idle. Update process times would miss the
- * time we slept as update_process_times does only a 1 tick
- * accounting. Enforce that this is accounted to idle !
- */
- ticks = jiffies - ts->idle_jiffies;
- /*
- * We might be one off. Do not randomly account a huge number of ticks!
- */
- if (ticks && ticks < LONG_MAX)
- account_idle_ticks(ticks);
-#endif
-
- calc_load_exit_idle();
- touch_softlockup_watchdog();
- /*
- * Cancel the scheduled timer and restore the tick
- */
- ts->tick_stopped = 0;
- ts->idle_exittime = now;
-
- tick_nohz_restart(ts, now);
-
local_irq_enable();
}
@@ -811,7 +835,8 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer)
*/
if (ts->tick_stopped) {
touch_softlockup_watchdog();
- ts->idle_jiffies++;
+ if (is_idle_task(current))
+ ts->idle_jiffies++;
}
update_process_times(user_mode(regs));
profile_tick(CPU_PROFILING);
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 3447cfaf11e..f791637597e 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -24,32 +24,32 @@
/* Structure holding internal timekeeping values. */
struct timekeeper {
/* Current clocksource used for timekeeping. */
- struct clocksource *clock;
+ struct clocksource *clock;
/* NTP adjusted clock multiplier */
- u32 mult;
+ u32 mult;
/* The shift value of the current clocksource. */
- int shift;
-
+ u32 shift;
/* Number of clock cycles in one NTP interval. */
- cycle_t cycle_interval;
+ cycle_t cycle_interval;
/* Number of clock shifted nano seconds in one NTP interval. */
- u64 xtime_interval;
+ u64 xtime_interval;
/* shifted nano seconds left over when rounding cycle_interval */
- s64 xtime_remainder;
+ s64 xtime_remainder;
/* Raw nano seconds accumulated per NTP interval. */
- u32 raw_interval;
+ u32 raw_interval;
+
+ /* Current CLOCK_REALTIME time in seconds */
+ u64 xtime_sec;
+ /* Clock shifted nano seconds */
+ u64 xtime_nsec;
- /* Clock shifted nano seconds remainder not stored in xtime.tv_nsec. */
- u64 xtime_nsec;
/* Difference between accumulated time and NTP time in ntp
* shifted nano seconds. */
- s64 ntp_error;
+ s64 ntp_error;
/* Shift conversion between clock shifted nano seconds and
* ntp shifted nano seconds. */
- int ntp_error_shift;
+ u32 ntp_error_shift;
- /* 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
@@ -64,20 +64,17 @@ struct timekeeper {
* - 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;
-
+ struct timespec wall_to_monotonic;
/* Offset clock monotonic -> clock realtime */
- ktime_t offs_real;
-
+ ktime_t offs_real;
+ /* time spent in suspend */
+ struct timespec total_sleep_time;
/* Offset clock monotonic -> clock boottime */
- ktime_t offs_boot;
-
+ ktime_t offs_boot;
+ /* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
+ struct timespec raw_time;
/* Seqlock for all timekeeper values */
- seqlock_t lock;
+ seqlock_t lock;
};
static struct timekeeper timekeeper;
@@ -88,11 +85,63 @@ static struct timekeeper timekeeper;
*/
__cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
-
/* flag for if timekeeping is suspended */
int __read_mostly timekeeping_suspended;
+static inline void tk_normalize_xtime(struct timekeeper *tk)
+{
+ while (tk->xtime_nsec >= ((u64)NSEC_PER_SEC << tk->shift)) {
+ tk->xtime_nsec -= (u64)NSEC_PER_SEC << tk->shift;
+ tk->xtime_sec++;
+ }
+}
+
+static struct timespec tk_xtime(struct timekeeper *tk)
+{
+ struct timespec ts;
+
+ ts.tv_sec = tk->xtime_sec;
+ ts.tv_nsec = (long)(tk->xtime_nsec >> tk->shift);
+ return ts;
+}
+
+static void tk_set_xtime(struct timekeeper *tk, const struct timespec *ts)
+{
+ tk->xtime_sec = ts->tv_sec;
+ tk->xtime_nsec = (u64)ts->tv_nsec << tk->shift;
+}
+static void tk_xtime_add(struct timekeeper *tk, const struct timespec *ts)
+{
+ tk->xtime_sec += ts->tv_sec;
+ tk->xtime_nsec += (u64)ts->tv_nsec << tk->shift;
+ tk_normalize_xtime(tk);
+}
+
+static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm)
+{
+ struct timespec tmp;
+
+ /*
+ * Verify consistency of: offset_real = -wall_to_monotonic
+ * before modifying anything
+ */
+ set_normalized_timespec(&tmp, -tk->wall_to_monotonic.tv_sec,
+ -tk->wall_to_monotonic.tv_nsec);
+ WARN_ON_ONCE(tk->offs_real.tv64 != timespec_to_ktime(tmp).tv64);
+ tk->wall_to_monotonic = wtm;
+ set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec);
+ tk->offs_real = timespec_to_ktime(tmp);
+}
+
+static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t)
+{
+ /* Verify consistency before modifying */
+ WARN_ON_ONCE(tk->offs_boot.tv64 != timespec_to_ktime(tk->total_sleep_time).tv64);
+
+ tk->total_sleep_time = t;
+ tk->offs_boot = timespec_to_ktime(t);
+}
/**
* timekeeper_setup_internals - Set up internals to use clocksource clock.
@@ -104,12 +153,14 @@ int __read_mostly timekeeping_suspended;
*
* Unless you're the timekeeping code, you should not be using this!
*/
-static void timekeeper_setup_internals(struct clocksource *clock)
+static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)
{
cycle_t interval;
u64 tmp, ntpinterval;
+ struct clocksource *old_clock;
- timekeeper.clock = clock;
+ old_clock = tk->clock;
+ tk->clock = clock;
clock->cycle_last = clock->read(clock);
/* Do the ns -> cycle conversion first, using original mult */
@@ -122,83 +173,89 @@ static void timekeeper_setup_internals(struct clocksource *clock)
tmp = 1;
interval = (cycle_t) tmp;
- timekeeper.cycle_interval = interval;
+ tk->cycle_interval = interval;
/* Go back from cycles -> shifted ns */
- timekeeper.xtime_interval = (u64) interval * clock->mult;
- timekeeper.xtime_remainder = ntpinterval - timekeeper.xtime_interval;
- timekeeper.raw_interval =
+ tk->xtime_interval = (u64) interval * clock->mult;
+ tk->xtime_remainder = ntpinterval - tk->xtime_interval;
+ tk->raw_interval =
((u64) interval * clock->mult) >> clock->shift;
- timekeeper.xtime_nsec = 0;
- timekeeper.shift = clock->shift;
+ /* if changing clocks, convert xtime_nsec shift units */
+ if (old_clock) {
+ int shift_change = clock->shift - old_clock->shift;
+ if (shift_change < 0)
+ tk->xtime_nsec >>= -shift_change;
+ else
+ tk->xtime_nsec <<= shift_change;
+ }
+ tk->shift = clock->shift;
- timekeeper.ntp_error = 0;
- timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;
+ tk->ntp_error = 0;
+ tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;
/*
* The timekeeper keeps its own mult values for the currently
* active clocksource. These value will be adjusted via NTP
* to counteract clock drifting.
*/
- timekeeper.mult = clock->mult;
+ tk->mult = clock->mult;
}
/* Timekeeper helper functions. */
-static inline s64 timekeeping_get_ns(void)
+static inline s64 timekeeping_get_ns(struct timekeeper *tk)
{
cycle_t cycle_now, cycle_delta;
struct clocksource *clock;
+ s64 nsec;
/* read clocksource: */
- clock = timekeeper.clock;
+ clock = tk->clock;
cycle_now = clock->read(clock);
/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
- /* return delta convert to nanoseconds using ntp adjusted mult. */
- return clocksource_cyc2ns(cycle_delta, timekeeper.mult,
- timekeeper.shift);
+ nsec = cycle_delta * tk->mult + tk->xtime_nsec;
+ nsec >>= tk->shift;
+
+ /* If arch requires, add in gettimeoffset() */
+ return nsec + arch_gettimeoffset();
}
-static inline s64 timekeeping_get_ns_raw(void)
+static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk)
{
cycle_t cycle_now, cycle_delta;
struct clocksource *clock;
+ s64 nsec;
/* read clocksource: */
- clock = timekeeper.clock;
+ clock = tk->clock;
cycle_now = clock->read(clock);
/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
- /* return delta convert to nanoseconds. */
- return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
-}
-
-static void update_rt_offset(void)
-{
- struct timespec tmp, *wtm = &timekeeper.wall_to_monotonic;
+ /* convert delta to nanoseconds. */
+ nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
- set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec);
- timekeeper.offs_real = timespec_to_ktime(tmp);
+ /* If arch requires, add in gettimeoffset() */
+ return nsec + arch_gettimeoffset();
}
/* must hold write on timekeeper.lock */
-static void timekeeping_update(bool clearntp)
+static void timekeeping_update(struct timekeeper *tk, bool clearntp)
{
+ struct timespec xt;
+
if (clearntp) {
- timekeeper.ntp_error = 0;
+ tk->ntp_error = 0;
ntp_clear();
}
- update_rt_offset();
- update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
- timekeeper.clock, timekeeper.mult);
+ xt = tk_xtime(tk);
+ update_vsyscall(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult);
}
-
/**
* timekeeping_forward_now - update clock to the current time
*
@@ -206,27 +263,26 @@ static void timekeeping_update(bool clearntp)
* update_wall_time(). This is useful before significant clock changes,
* as it avoids having to deal with this time offset explicitly.
*/
-static void timekeeping_forward_now(void)
+static void timekeeping_forward_now(struct timekeeper *tk)
{
cycle_t cycle_now, cycle_delta;
struct clocksource *clock;
s64 nsec;
- clock = timekeeper.clock;
+ clock = tk->clock;
cycle_now = clock->read(clock);
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
clock->cycle_last = cycle_now;
- nsec = clocksource_cyc2ns(cycle_delta, timekeeper.mult,
- timekeeper.shift);
+ tk->xtime_nsec += cycle_delta * tk->mult;
/* If arch requires, add in gettimeoffset() */
- nsec += arch_gettimeoffset();
+ tk->xtime_nsec += (u64)arch_gettimeoffset() << tk->shift;
- timespec_add_ns(&timekeeper.xtime, nsec);
+ tk_normalize_xtime(tk);
nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
- timespec_add_ns(&timekeeper.raw_time, nsec);
+ timespec_add_ns(&tk->raw_time, nsec);
}
/**
@@ -237,44 +293,39 @@ static void timekeeping_forward_now(void)
*/
void getnstimeofday(struct timespec *ts)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long seq;
- s64 nsecs;
+ s64 nsecs = 0;
WARN_ON(timekeeping_suspended);
do {
- seq = read_seqbegin(&timekeeper.lock);
-
- *ts = timekeeper.xtime;
- nsecs = timekeeping_get_ns();
+ seq = read_seqbegin(&tk->lock);
- /* If arch requires, add in gettimeoffset() */
- nsecs += arch_gettimeoffset();
+ ts->tv_sec = tk->xtime_sec;
+ nsecs = timekeeping_get_ns(tk);
- } while (read_seqretry(&timekeeper.lock, seq));
+ } while (read_seqretry(&tk->lock, seq));
+ ts->tv_nsec = 0;
timespec_add_ns(ts, nsecs);
}
EXPORT_SYMBOL(getnstimeofday);
ktime_t ktime_get(void)
{
+ struct timekeeper *tk = &timekeeper;
unsigned int seq;
s64 secs, nsecs;
WARN_ON(timekeeping_suspended);
do {
- 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(&timekeeper.lock, seq));
+ seq = read_seqbegin(&tk->lock);
+ secs = tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
+ nsecs = timekeeping_get_ns(tk) + tk->wall_to_monotonic.tv_nsec;
+
+ } while (read_seqretry(&tk->lock, seq));
/*
* Use ktime_set/ktime_add_ns to create a proper ktime on
* 32-bit architectures without CONFIG_KTIME_SCALAR.
@@ -293,24 +344,24 @@ EXPORT_SYMBOL_GPL(ktime_get);
*/
void ktime_get_ts(struct timespec *ts)
{
+ struct timekeeper *tk = &timekeeper;
struct timespec tomono;
+ s64 nsec;
unsigned int seq;
- s64 nsecs;
WARN_ON(timekeeping_suspended);
do {
- 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();
+ seq = read_seqbegin(&tk->lock);
+ ts->tv_sec = tk->xtime_sec;
+ nsec = timekeeping_get_ns(tk);
+ tomono = tk->wall_to_monotonic;
- } while (read_seqretry(&timekeeper.lock, seq));
+ } while (read_seqretry(&tk->lock, seq));
- set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
- ts->tv_nsec + tomono.tv_nsec + nsecs);
+ ts->tv_sec += tomono.tv_sec;
+ ts->tv_nsec = 0;
+ timespec_add_ns(ts, nsec + tomono.tv_nsec);
}
EXPORT_SYMBOL_GPL(ktime_get_ts);
@@ -327,28 +378,23 @@ EXPORT_SYMBOL_GPL(ktime_get_ts);
*/
void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long seq;
s64 nsecs_raw, nsecs_real;
WARN_ON_ONCE(timekeeping_suspended);
do {
- u32 arch_offset;
-
- seq = read_seqbegin(&timekeeper.lock);
+ seq = read_seqbegin(&tk->lock);
- *ts_raw = timekeeper.raw_time;
- *ts_real = timekeeper.xtime;
+ *ts_raw = tk->raw_time;
+ ts_real->tv_sec = tk->xtime_sec;
+ ts_real->tv_nsec = 0;
- nsecs_raw = timekeeping_get_ns_raw();
- nsecs_real = timekeeping_get_ns();
+ nsecs_raw = timekeeping_get_ns_raw(tk);
+ nsecs_real = timekeeping_get_ns(tk);
- /* If arch requires, add in gettimeoffset() */
- arch_offset = arch_gettimeoffset();
- nsecs_raw += arch_offset;
- nsecs_real += arch_offset;
-
- } while (read_seqretry(&timekeeper.lock, seq));
+ } while (read_seqretry(&tk->lock, seq));
timespec_add_ns(ts_raw, nsecs_raw);
timespec_add_ns(ts_real, nsecs_real);
@@ -381,25 +427,28 @@ EXPORT_SYMBOL(do_gettimeofday);
*/
int do_settimeofday(const struct timespec *tv)
{
- struct timespec ts_delta;
+ struct timekeeper *tk = &timekeeper;
+ struct timespec ts_delta, xt;
unsigned long flags;
- if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
+ if (!timespec_valid_strict(tv))
return -EINVAL;
- write_seqlock_irqsave(&timekeeper.lock, flags);
+ write_seqlock_irqsave(&tk->lock, flags);
+
+ timekeeping_forward_now(tk);
- timekeeping_forward_now();
+ xt = tk_xtime(tk);
+ ts_delta.tv_sec = tv->tv_sec - xt.tv_sec;
+ ts_delta.tv_nsec = tv->tv_nsec - xt.tv_nsec;
- 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);
+ tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, ts_delta));
- timekeeper.xtime = *tv;
- timekeeping_update(true);
+ tk_set_xtime(tk, tv);
- write_sequnlock_irqrestore(&timekeeper.lock, flags);
+ timekeeping_update(tk, true);
+
+ write_sequnlock_irqrestore(&tk->lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@@ -408,7 +457,6 @@ int do_settimeofday(const struct timespec *tv)
}
EXPORT_SYMBOL(do_settimeofday);
-
/**
* timekeeping_inject_offset - Adds or subtracts from the current time.
* @tv: pointer to the timespec variable containing the offset
@@ -417,27 +465,37 @@ EXPORT_SYMBOL(do_settimeofday);
*/
int timekeeping_inject_offset(struct timespec *ts)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long flags;
+ struct timespec tmp;
+ int ret = 0;
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
- write_seqlock_irqsave(&timekeeper.lock, flags);
+ write_seqlock_irqsave(&tk->lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(tk);
- timekeeper.xtime = timespec_add(timekeeper.xtime, *ts);
- timekeeper.wall_to_monotonic =
- timespec_sub(timekeeper.wall_to_monotonic, *ts);
+ /* Make sure the proposed value is valid */
+ tmp = timespec_add(tk_xtime(tk), *ts);
+ if (!timespec_valid_strict(&tmp)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ tk_xtime_add(tk, ts);
+ tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *ts));
- timekeeping_update(true);
+error: /* even if we error out, we forwarded the time, so call update */
+ timekeeping_update(tk, true);
- write_sequnlock_irqrestore(&timekeeper.lock, flags);
+ write_sequnlock_irqrestore(&tk->lock, flags);
/* signal hrtimers about time change */
clock_was_set();
- return 0;
+ return ret;
}
EXPORT_SYMBOL(timekeeping_inject_offset);
@@ -448,23 +506,24 @@ EXPORT_SYMBOL(timekeeping_inject_offset);
*/
static int change_clocksource(void *data)
{
+ struct timekeeper *tk = &timekeeper;
struct clocksource *new, *old;
unsigned long flags;
new = (struct clocksource *) data;
- write_seqlock_irqsave(&timekeeper.lock, flags);
+ write_seqlock_irqsave(&tk->lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(tk);
if (!new->enable || new->enable(new) == 0) {
- old = timekeeper.clock;
- timekeeper_setup_internals(new);
+ old = tk->clock;
+ tk_setup_internals(tk, new);
if (old->disable)
old->disable(old);
}
- timekeeping_update(true);
+ timekeeping_update(tk, true);
- write_sequnlock_irqrestore(&timekeeper.lock, flags);
+ write_sequnlock_irqrestore(&tk->lock, flags);
return 0;
}
@@ -478,7 +537,9 @@ static int change_clocksource(void *data)
*/
void timekeeping_notify(struct clocksource *clock)
{
- if (timekeeper.clock == clock)
+ struct timekeeper *tk = &timekeeper;
+
+ if (tk->clock == clock)
return;
stop_machine(change_clocksource, clock, NULL);
tick_clock_notify();
@@ -507,35 +568,36 @@ EXPORT_SYMBOL_GPL(ktime_get_real);
*/
void getrawmonotonic(struct timespec *ts)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long seq;
s64 nsecs;
do {
- seq = read_seqbegin(&timekeeper.lock);
- nsecs = timekeeping_get_ns_raw();
- *ts = timekeeper.raw_time;
+ seq = read_seqbegin(&tk->lock);
+ nsecs = timekeeping_get_ns_raw(tk);
+ *ts = tk->raw_time;
- } while (read_seqretry(&timekeeper.lock, seq));
+ } while (read_seqretry(&tk->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)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long seq;
int ret;
do {
- seq = read_seqbegin(&timekeeper.lock);
+ seq = read_seqbegin(&tk->lock);
- ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
+ ret = tk->clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
- } while (read_seqretry(&timekeeper.lock, seq));
+ } while (read_seqretry(&tk->lock, seq));
return ret;
}
@@ -545,14 +607,16 @@ int timekeeping_valid_for_hres(void)
*/
u64 timekeeping_max_deferment(void)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long seq;
u64 ret;
+
do {
- seq = read_seqbegin(&timekeeper.lock);
+ seq = read_seqbegin(&tk->lock);
- ret = timekeeper.clock->max_idle_ns;
+ ret = tk->clock->max_idle_ns;
- } while (read_seqretry(&timekeeper.lock, seq));
+ } while (read_seqretry(&tk->lock, seq));
return ret;
}
@@ -592,48 +656,56 @@ void __attribute__((weak)) read_boot_clock(struct timespec *ts)
*/
void __init timekeeping_init(void)
{
+ struct timekeeper *tk = &timekeeper;
struct clocksource *clock;
unsigned long flags;
- struct timespec now, boot;
+ struct timespec now, boot, tmp;
read_persistent_clock(&now);
+ if (!timespec_valid_strict(&now)) {
+ pr_warn("WARNING: Persistent clock returned invalid value!\n"
+ " Check your CMOS/BIOS settings.\n");
+ now.tv_sec = 0;
+ now.tv_nsec = 0;
+ }
+
read_boot_clock(&boot);
+ if (!timespec_valid_strict(&boot)) {
+ pr_warn("WARNING: Boot clock returned invalid value!\n"
+ " Check your CMOS/BIOS settings.\n");
+ boot.tv_sec = 0;
+ boot.tv_nsec = 0;
+ }
- seqlock_init(&timekeeper.lock);
+ seqlock_init(&tk->lock);
ntp_init();
- write_seqlock_irqsave(&timekeeper.lock, flags);
+ write_seqlock_irqsave(&tk->lock, flags);
clock = clocksource_default_clock();
if (clock->enable)
clock->enable(clock);
- timekeeper_setup_internals(clock);
-
- 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 = timekeeper.xtime.tv_sec;
- boot.tv_nsec = timekeeper.xtime.tv_nsec;
- }
- 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);
+ tk_setup_internals(tk, clock);
+
+ tk_set_xtime(tk, &now);
+ tk->raw_time.tv_sec = 0;
+ tk->raw_time.tv_nsec = 0;
+ if (boot.tv_sec == 0 && boot.tv_nsec == 0)
+ boot = tk_xtime(tk);
+
+ set_normalized_timespec(&tmp, -boot.tv_sec, -boot.tv_nsec);
+ tk_set_wall_to_mono(tk, tmp);
+
+ tmp.tv_sec = 0;
+ tmp.tv_nsec = 0;
+ tk_set_sleep_time(tk, tmp);
+
+ write_sequnlock_irqrestore(&tk->lock, flags);
}
/* 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
@@ -641,21 +713,19 @@ static void update_sleep_time(struct timespec t)
* Takes a timespec offset measuring a suspend interval and properly
* adds the sleep offset to the timekeeping variables.
*/
-static void __timekeeping_inject_sleeptime(struct timespec *delta)
+static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
+ struct timespec *delta)
{
- if (!timespec_valid(delta)) {
+ if (!timespec_valid_strict(delta)) {
printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid "
"sleep delta value!\n");
return;
}
-
- timekeeper.xtime = timespec_add(timekeeper.xtime, *delta);
- timekeeper.wall_to_monotonic =
- timespec_sub(timekeeper.wall_to_monotonic, *delta);
- update_sleep_time(timespec_add(timekeeper.total_sleep_time, *delta));
+ tk_xtime_add(tk, delta);
+ tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *delta));
+ tk_set_sleep_time(tk, timespec_add(tk->total_sleep_time, *delta));
}
-
/**
* timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values
* @delta: pointer to a timespec delta value
@@ -668,6 +738,7 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
*/
void timekeeping_inject_sleeptime(struct timespec *delta)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long flags;
struct timespec ts;
@@ -676,21 +747,20 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
if (!(ts.tv_sec == 0 && ts.tv_nsec == 0))
return;
- write_seqlock_irqsave(&timekeeper.lock, flags);
+ write_seqlock_irqsave(&tk->lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(tk);
- __timekeeping_inject_sleeptime(delta);
+ __timekeeping_inject_sleeptime(tk, delta);
- timekeeping_update(true);
+ timekeeping_update(tk, true);
- write_sequnlock_irqrestore(&timekeeper.lock, flags);
+ write_sequnlock_irqrestore(&tk->lock, flags);
/* signal hrtimers about time change */
clock_was_set();
}
-
/**
* timekeeping_resume - Resumes the generic timekeeping subsystem.
*
@@ -700,6 +770,7 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
*/
static void timekeeping_resume(void)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long flags;
struct timespec ts;
@@ -707,18 +778,18 @@ static void timekeeping_resume(void)
clocksource_resume();
- write_seqlock_irqsave(&timekeeper.lock, flags);
+ write_seqlock_irqsave(&tk->lock, flags);
if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
ts = timespec_sub(ts, timekeeping_suspend_time);
- __timekeeping_inject_sleeptime(&ts);
+ __timekeeping_inject_sleeptime(tk, &ts);
}
/* re-base the last cycle value */
- timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
- timekeeper.ntp_error = 0;
+ tk->clock->cycle_last = tk->clock->read(tk->clock);
+ tk->ntp_error = 0;
timekeeping_suspended = 0;
- timekeeping_update(false);
- write_sequnlock_irqrestore(&timekeeper.lock, flags);
+ timekeeping_update(tk, false);
+ write_sequnlock_irqrestore(&tk->lock, flags);
touch_softlockup_watchdog();
@@ -730,14 +801,15 @@ static void timekeeping_resume(void)
static int timekeeping_suspend(void)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long flags;
struct timespec delta, delta_delta;
static struct timespec old_delta;
read_persistent_clock(&timekeeping_suspend_time);
- write_seqlock_irqsave(&timekeeper.lock, flags);
- timekeeping_forward_now();
+ write_seqlock_irqsave(&tk->lock, flags);
+ timekeeping_forward_now(tk);
timekeeping_suspended = 1;
/*
@@ -746,7 +818,7 @@ 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(timekeeper.xtime, timekeeping_suspend_time);
+ delta = timespec_sub(tk_xtime(tk), timekeeping_suspend_time);
delta_delta = timespec_sub(delta, old_delta);
if (abs(delta_delta.tv_sec) >= 2) {
/*
@@ -759,7 +831,7 @@ static int timekeeping_suspend(void)
timekeeping_suspend_time =
timespec_add(timekeeping_suspend_time, delta_delta);
}
- write_sequnlock_irqrestore(&timekeeper.lock, flags);
+ write_sequnlock_irqrestore(&tk->lock, flags);
clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
clocksource_suspend();
@@ -785,7 +857,8 @@ device_initcall(timekeeping_init_ops);
* If the error is already larger, we look ahead even further
* to compensate for late or lost adjustments.
*/
-static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
+static __always_inline int timekeeping_bigadjust(struct timekeeper *tk,
+ s64 error, s64 *interval,
s64 *offset)
{
s64 tick_error, i;
@@ -801,7 +874,7 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
* here. This is tuned so that an error of about 1 msec is adjusted
* within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks).
*/
- error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
+ error2 = tk->ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
error2 = abs(error2);
for (look_ahead = 0; error2 > 0; look_ahead++)
error2 >>= 2;
@@ -810,8 +883,8 @@ 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 = ntp_tick_length() >> (timekeeper.ntp_error_shift + 1);
- tick_error -= timekeeper.xtime_interval >> 1;
+ tick_error = ntp_tick_length() >> (tk->ntp_error_shift + 1);
+ tick_error -= tk->xtime_interval >> 1;
error = ((error - tick_error) >> look_ahead) + tick_error;
/* Finally calculate the adjustment shift value. */
@@ -836,9 +909,9 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
* this is optimized for the most common adjustments of -1,0,1,
* for other values we can do a bit more work.
*/
-static void timekeeping_adjust(s64 offset)
+static void timekeeping_adjust(struct timekeeper *tk, s64 offset)
{
- s64 error, interval = timekeeper.cycle_interval;
+ s64 error, interval = tk->cycle_interval;
int adj;
/*
@@ -854,7 +927,7 @@ static void timekeeping_adjust(s64 offset)
*
* Note: It does not "save" on aggravation when reading the code.
*/
- error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1);
+ error = tk->ntp_error >> (tk->ntp_error_shift - 1);
if (error > interval) {
/*
* We now divide error by 4(via shift), which checks if
@@ -869,34 +942,36 @@ static void timekeeping_adjust(s64 offset)
* the error. This causes the likely below to be unlikely.
*
* The proper fix is to avoid rounding up by using
- * the high precision timekeeper.xtime_nsec instead of
+ * the high precision tk->xtime_nsec instead of
* xtime.tv_nsec everywhere. Fixing this will take some
* time.
*/
if (likely(error <= interval))
adj = 1;
else
- adj = timekeeping_bigadjust(error, &interval, &offset);
- } else if (error < -interval) {
- /* See comment above, this is just switched for the negative */
- error >>= 2;
- if (likely(error >= -interval)) {
- adj = -1;
- interval = -interval;
- offset = -offset;
- } else
- adj = timekeeping_bigadjust(error, &interval, &offset);
- } else /* No adjustment needed */
- return;
+ adj = timekeeping_bigadjust(tk, error, &interval, &offset);
+ } else {
+ if (error < -interval) {
+ /* See comment above, this is just switched for the negative */
+ error >>= 2;
+ if (likely(error >= -interval)) {
+ adj = -1;
+ interval = -interval;
+ offset = -offset;
+ } else {
+ adj = timekeeping_bigadjust(tk, error, &interval, &offset);
+ }
+ } else {
+ goto out_adjust;
+ }
+ }
- if (unlikely(timekeeper.clock->maxadj &&
- (timekeeper.mult + adj >
- timekeeper.clock->mult + timekeeper.clock->maxadj))) {
+ if (unlikely(tk->clock->maxadj &&
+ (tk->mult + adj > tk->clock->mult + tk->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);
+ tk->clock->name, (long)tk->mult + adj,
+ (long)tk->clock->mult + tk->clock->maxadj);
}
/*
* So the following can be confusing.
@@ -947,13 +1022,68 @@ static void timekeeping_adjust(s64 offset)
*
* XXX - TODO: Doc ntp_error calculation.
*/
- timekeeper.mult += adj;
- timekeeper.xtime_interval += interval;
- timekeeper.xtime_nsec -= offset;
- timekeeper.ntp_error -= (interval - offset) <<
- timekeeper.ntp_error_shift;
+ tk->mult += adj;
+ tk->xtime_interval += interval;
+ tk->xtime_nsec -= offset;
+ tk->ntp_error -= (interval - offset) << tk->ntp_error_shift;
+
+out_adjust:
+ /*
+ * It may be possible that when we entered this function, xtime_nsec
+ * was very small. Further, if we're slightly speeding the clocksource
+ * in the code above, its possible the required corrective factor to
+ * xtime_nsec could cause it to underflow.
+ *
+ * Now, since we already accumulated the second, cannot simply roll
+ * the accumulated second back, since the NTP subsystem has been
+ * notified via second_overflow. So instead we push xtime_nsec forward
+ * by the amount we underflowed, and add that amount into the error.
+ *
+ * We'll correct this error next time through this function, when
+ * xtime_nsec is not as small.
+ */
+ if (unlikely((s64)tk->xtime_nsec < 0)) {
+ s64 neg = -(s64)tk->xtime_nsec;
+ tk->xtime_nsec = 0;
+ tk->ntp_error += neg << tk->ntp_error_shift;
+ }
+
}
+/**
+ * accumulate_nsecs_to_secs - Accumulates nsecs into secs
+ *
+ * Helper function that accumulates a the nsecs greater then a second
+ * from the xtime_nsec field to the xtime_secs field.
+ * It also calls into the NTP code to handle leapsecond processing.
+ *
+ */
+static inline void accumulate_nsecs_to_secs(struct timekeeper *tk)
+{
+ u64 nsecps = (u64)NSEC_PER_SEC << tk->shift;
+
+ while (tk->xtime_nsec >= nsecps) {
+ int leap;
+
+ tk->xtime_nsec -= nsecps;
+ tk->xtime_sec++;
+
+ /* Figure out if its a leap sec and apply if needed */
+ leap = second_overflow(tk->xtime_sec);
+ if (unlikely(leap)) {
+ struct timespec ts;
+
+ tk->xtime_sec += leap;
+
+ ts.tv_sec = leap;
+ ts.tv_nsec = 0;
+ tk_set_wall_to_mono(tk,
+ timespec_sub(tk->wall_to_monotonic, ts));
+
+ clock_was_set_delayed();
+ }
+ }
+}
/**
* logarithmic_accumulation - shifted accumulation of cycles
@@ -964,51 +1094,40 @@ static void timekeeping_adjust(s64 offset)
*
* Returns the unconsumed cycles.
*/
-static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
+static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,
+ u32 shift)
{
- u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
u64 raw_nsecs;
- /* If the offset is smaller than a shifted interval, do nothing */
- if (offset < timekeeper.cycle_interval<<shift)
+ /* If the offset is smaller then a shifted interval, do nothing */
+ if (offset < tk->cycle_interval<<shift)
return offset;
/* Accumulate one shifted interval */
- offset -= timekeeper.cycle_interval << shift;
- timekeeper.clock->cycle_last += timekeeper.cycle_interval << shift;
+ offset -= tk->cycle_interval << shift;
+ tk->clock->cycle_last += tk->cycle_interval << shift;
- timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;
- while (timekeeper.xtime_nsec >= nsecps) {
- int leap;
- timekeeper.xtime_nsec -= nsecps;
- timekeeper.xtime.tv_sec++;
- 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();
- }
+ tk->xtime_nsec += tk->xtime_interval << shift;
+ accumulate_nsecs_to_secs(tk);
/* Accumulate raw time */
- raw_nsecs = timekeeper.raw_interval << shift;
- raw_nsecs += timekeeper.raw_time.tv_nsec;
+ raw_nsecs = (u64)tk->raw_interval << shift;
+ raw_nsecs += tk->raw_time.tv_nsec;
if (raw_nsecs >= NSEC_PER_SEC) {
u64 raw_secs = raw_nsecs;
raw_nsecs = do_div(raw_secs, NSEC_PER_SEC);
- timekeeper.raw_time.tv_sec += raw_secs;
+ tk->raw_time.tv_sec += raw_secs;
}
- timekeeper.raw_time.tv_nsec = raw_nsecs;
+ tk->raw_time.tv_nsec = raw_nsecs;
/* Accumulate error between NTP and clock interval */
- timekeeper.ntp_error += ntp_tick_length() << shift;
- timekeeper.ntp_error -=
- (timekeeper.xtime_interval + timekeeper.xtime_remainder) <<
- (timekeeper.ntp_error_shift + shift);
+ tk->ntp_error += ntp_tick_length() << shift;
+ tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) <<
+ (tk->ntp_error_shift + shift);
return offset;
}
-
/**
* update_wall_time - Uses the current clocksource to increment the wall time
*
@@ -1016,25 +1135,29 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
static void update_wall_time(void)
{
struct clocksource *clock;
+ struct timekeeper *tk = &timekeeper;
cycle_t offset;
int shift = 0, maxshift;
unsigned long flags;
+ s64 remainder;
- write_seqlock_irqsave(&timekeeper.lock, flags);
+ write_seqlock_irqsave(&tk->lock, flags);
/* Make sure we're fully resumed: */
if (unlikely(timekeeping_suspended))
goto out;
- clock = timekeeper.clock;
+ clock = tk->clock;
#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
- offset = timekeeper.cycle_interval;
+ offset = tk->cycle_interval;
#else
offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
#endif
- timekeeper.xtime_nsec = (s64)timekeeper.xtime.tv_nsec <<
- timekeeper.shift;
+
+ /* Check if there's really nothing to do */
+ if (offset < tk->cycle_interval)
+ goto out;
/*
* With NO_HZ we may have to accumulate many cycle_intervals
@@ -1044,73 +1167,45 @@ static void update_wall_time(void)
* chunk in one go, and then try to consume the next smaller
* doubled multiple.
*/
- shift = ilog2(offset) - ilog2(timekeeper.cycle_interval);
+ shift = ilog2(offset) - ilog2(tk->cycle_interval);
shift = max(0, shift);
/* 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);
- if(offset < timekeeper.cycle_interval<<shift)
+ while (offset >= tk->cycle_interval) {
+ offset = logarithmic_accumulation(tk, offset, shift);
+ if (offset < tk->cycle_interval<<shift)
shift--;
}
/* correct the clock when NTP error is too big */
- timekeeping_adjust(offset);
-
- /*
- * Since in the loop above, we accumulate any amount of time
- * in xtime_nsec over a second into xtime.tv_sec, its possible for
- * xtime_nsec to be fairly small after the loop. Further, if we're
- * slightly speeding the clocksource up in timekeeping_adjust(),
- * its possible the required corrective factor to xtime_nsec could
- * cause it to underflow.
- *
- * Now, we cannot simply roll the accumulated second back, since
- * the NTP subsystem has been notified via second_overflow. So
- * instead we push xtime_nsec forward by the amount we underflowed,
- * and add that amount into the error.
- *
- * We'll correct this error next time through this function, when
- * xtime_nsec is not as small.
- */
- if (unlikely((s64)timekeeper.xtime_nsec < 0)) {
- s64 neg = -(s64)timekeeper.xtime_nsec;
- timekeeper.xtime_nsec = 0;
- timekeeper.ntp_error += neg << timekeeper.ntp_error_shift;
- }
+ timekeeping_adjust(tk, offset);
/*
- * Store full nanoseconds into xtime after rounding it up and
- * add the remainder to the error difference.
- */
- 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;
+ * Store only full nanoseconds into xtime_nsec after rounding
+ * it up and add the remainder to the error difference.
+ * XXX - This is necessary to avoid small 1ns inconsistnecies caused
+ * by truncating the remainder in vsyscalls. However, it causes
+ * additional work to be done in timekeeping_adjust(). Once
+ * the vsyscall implementations are converted to use xtime_nsec
+ * (shifted nanoseconds), this can be killed.
+ */
+ remainder = tk->xtime_nsec & ((1ULL << tk->shift) - 1);
+ tk->xtime_nsec -= remainder;
+ tk->xtime_nsec += 1ULL << tk->shift;
+ tk->ntp_error += remainder << tk->ntp_error_shift;
/*
* Finally, make sure that after the rounding
- * xtime.tv_nsec isn't larger than NSEC_PER_SEC
+ * xtime_nsec isn't larger than NSEC_PER_SEC
*/
- 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;
- timekeeper.wall_to_monotonic.tv_sec -= leap;
- if (leap)
- clock_was_set_delayed();
- }
+ accumulate_nsecs_to_secs(tk);
- timekeeping_update(false);
+ timekeeping_update(tk, false);
out:
- write_sequnlock_irqrestore(&timekeeper.lock, flags);
+ write_sequnlock_irqrestore(&tk->lock, flags);
}
@@ -1127,18 +1222,18 @@ out:
*/
void getboottime(struct timespec *ts)
{
+ struct timekeeper *tk = &timekeeper;
struct timespec boottime = {
- .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
+ .tv_sec = tk->wall_to_monotonic.tv_sec +
+ tk->total_sleep_time.tv_sec,
+ .tv_nsec = tk->wall_to_monotonic.tv_nsec +
+ tk->total_sleep_time.tv_nsec
};
set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec);
}
EXPORT_SYMBOL_GPL(getboottime);
-
/**
* get_monotonic_boottime - Returns monotonic time since boot
* @ts: pointer to the timespec to be set
@@ -1150,23 +1245,25 @@ EXPORT_SYMBOL_GPL(getboottime);
*/
void get_monotonic_boottime(struct timespec *ts)
{
+ struct timekeeper *tk = &timekeeper;
struct timespec tomono, sleep;
+ s64 nsec;
unsigned int seq;
- s64 nsecs;
WARN_ON(timekeeping_suspended);
do {
- seq = read_seqbegin(&timekeeper.lock);
- *ts = timekeeper.xtime;
- tomono = timekeeper.wall_to_monotonic;
- sleep = timekeeper.total_sleep_time;
- nsecs = timekeeping_get_ns();
+ seq = read_seqbegin(&tk->lock);
+ ts->tv_sec = tk->xtime_sec;
+ nsec = timekeeping_get_ns(tk);
+ tomono = tk->wall_to_monotonic;
+ sleep = tk->total_sleep_time;
- } while (read_seqretry(&timekeeper.lock, seq));
+ } while (read_seqretry(&tk->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);
+ ts->tv_sec += tomono.tv_sec + sleep.tv_sec;
+ ts->tv_nsec = 0;
+ timespec_add_ns(ts, nsec + tomono.tv_nsec + sleep.tv_nsec);
}
EXPORT_SYMBOL_GPL(get_monotonic_boottime);
@@ -1193,31 +1290,38 @@ EXPORT_SYMBOL_GPL(ktime_get_boottime);
*/
void monotonic_to_bootbased(struct timespec *ts)
{
- *ts = timespec_add(*ts, timekeeper.total_sleep_time);
+ struct timekeeper *tk = &timekeeper;
+
+ *ts = timespec_add(*ts, tk->total_sleep_time);
}
EXPORT_SYMBOL_GPL(monotonic_to_bootbased);
unsigned long get_seconds(void)
{
- return timekeeper.xtime.tv_sec;
+ struct timekeeper *tk = &timekeeper;
+
+ return tk->xtime_sec;
}
EXPORT_SYMBOL(get_seconds);
struct timespec __current_kernel_time(void)
{
- return timekeeper.xtime;
+ struct timekeeper *tk = &timekeeper;
+
+ return tk_xtime(tk);
}
struct timespec current_kernel_time(void)
{
+ struct timekeeper *tk = &timekeeper;
struct timespec now;
unsigned long seq;
do {
- seq = read_seqbegin(&timekeeper.lock);
+ seq = read_seqbegin(&tk->lock);
- now = timekeeper.xtime;
- } while (read_seqretry(&timekeeper.lock, seq));
+ now = tk_xtime(tk);
+ } while (read_seqretry(&tk->lock, seq));
return now;
}
@@ -1225,15 +1329,16 @@ EXPORT_SYMBOL(current_kernel_time);
struct timespec get_monotonic_coarse(void)
{
+ struct timekeeper *tk = &timekeeper;
struct timespec now, mono;
unsigned long seq;
do {
- seq = read_seqbegin(&timekeeper.lock);
+ seq = read_seqbegin(&tk->lock);
- now = timekeeper.xtime;
- mono = timekeeper.wall_to_monotonic;
- } while (read_seqretry(&timekeeper.lock, seq));
+ now = tk_xtime(tk);
+ mono = tk->wall_to_monotonic;
+ } while (read_seqretry(&tk->lock, seq));
set_normalized_timespec(&now, now.tv_sec + mono.tv_sec,
now.tv_nsec + mono.tv_nsec);
@@ -1262,14 +1367,15 @@ void do_timer(unsigned long ticks)
void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
struct timespec *wtom, struct timespec *sleep)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long seq;
do {
- seq = read_seqbegin(&timekeeper.lock);
- *xtim = timekeeper.xtime;
- *wtom = timekeeper.wall_to_monotonic;
- *sleep = timekeeper.total_sleep_time;
- } while (read_seqretry(&timekeeper.lock, seq));
+ seq = read_seqbegin(&tk->lock);
+ *xtim = tk_xtime(tk);
+ *wtom = tk->wall_to_monotonic;
+ *sleep = tk->total_sleep_time;
+ } while (read_seqretry(&tk->lock, seq));
}
#ifdef CONFIG_HIGH_RES_TIMERS
@@ -1283,22 +1389,20 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
*/
ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
{
+ struct timekeeper *tk = &timekeeper;
ktime_t now;
unsigned int seq;
u64 secs, nsecs;
do {
- seq = read_seqbegin(&timekeeper.lock);
+ seq = read_seqbegin(&tk->lock);
- secs = timekeeper.xtime.tv_sec;
- nsecs = timekeeper.xtime.tv_nsec;
- nsecs += timekeeping_get_ns();
- /* If arch requires, add in gettimeoffset() */
- nsecs += arch_gettimeoffset();
+ secs = tk->xtime_sec;
+ nsecs = timekeeping_get_ns(tk);
- *offs_real = timekeeper.offs_real;
- *offs_boot = timekeeper.offs_boot;
- } while (read_seqretry(&timekeeper.lock, seq));
+ *offs_real = tk->offs_real;
+ *offs_boot = tk->offs_boot;
+ } while (read_seqretry(&tk->lock, seq));
now = ktime_add_ns(ktime_set(secs, 0), nsecs);
now = ktime_sub(now, *offs_real);
@@ -1311,19 +1415,19 @@ ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
*/
ktime_t ktime_get_monotonic_offset(void)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long seq;
struct timespec wtom;
do {
- seq = read_seqbegin(&timekeeper.lock);
- wtom = timekeeper.wall_to_monotonic;
- } while (read_seqretry(&timekeeper.lock, seq));
+ seq = read_seqbegin(&tk->lock);
+ wtom = tk->wall_to_monotonic;
+ } while (read_seqretry(&tk->lock, seq));
return timespec_to_ktime(wtom);
}
EXPORT_SYMBOL_GPL(ktime_get_monotonic_offset);
-
/**
* xtime_update() - advances the timekeeping infrastructure
* @ticks: number of ticks, that have elapsed since the last call.
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index 3258455549f..af5a7e9f164 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -167,7 +167,7 @@ static void print_cpu(struct seq_file *m, int cpu, u64 now)
{
struct tick_sched *ts = tick_get_tick_sched(cpu);
P(nohz_mode);
- P_ns(idle_tick);
+ P_ns(last_tick);
P(tick_stopped);
P(idle_jiffies);
P(idle_calls);
@@ -259,7 +259,7 @@ 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: v0.6\n");
+ SEQ_printf(m, "Timer List Version: v0.7\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);