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Diffstat (limited to 'kernel/timer.c')
-rw-r--r--kernel/timer.c342
1 files changed, 138 insertions, 204 deletions
diff --git a/kernel/timer.c b/kernel/timer.c
index 6a2e5f8dc72..fd74268d866 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -46,6 +46,10 @@ static void time_interpolator_update(long delta_nsec);
#define time_interpolator_update(x)
#endif
+u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
/*
* per-CPU timer vector definitions:
*/
@@ -91,30 +95,6 @@ static inline void set_running_timer(tvec_base_t *base,
#endif
}
-static void check_timer_failed(struct timer_list *timer)
-{
- static int whine_count;
- if (whine_count < 16) {
- whine_count++;
- printk("Uninitialised timer!\n");
- printk("This is just a warning. Your computer is OK\n");
- printk("function=0x%p, data=0x%lx\n",
- timer->function, timer->data);
- dump_stack();
- }
- /*
- * Now fix it up
- */
- timer->magic = TIMER_MAGIC;
-}
-
-static inline void check_timer(struct timer_list *timer)
-{
- if (timer->magic != TIMER_MAGIC)
- check_timer_failed(timer);
-}
-
-
static void internal_add_timer(tvec_base_t *base, struct timer_list *timer)
{
unsigned long expires = timer->expires;
@@ -177,7 +157,6 @@ void fastcall init_timer(struct timer_list *timer)
{
timer->entry.next = NULL;
timer->base = &per_cpu(tvec_bases, raw_smp_processor_id()).t_base;
- timer->magic = TIMER_MAGIC;
}
EXPORT_SYMBOL(init_timer);
@@ -230,7 +209,6 @@ int __mod_timer(struct timer_list *timer, unsigned long expires)
int ret = 0;
BUG_ON(!timer->function);
- check_timer(timer);
base = lock_timer_base(timer, &flags);
@@ -283,9 +261,6 @@ void add_timer_on(struct timer_list *timer, int cpu)
unsigned long flags;
BUG_ON(timer_pending(timer) || !timer->function);
-
- check_timer(timer);
-
spin_lock_irqsave(&base->t_base.lock, flags);
timer->base = &base->t_base;
internal_add_timer(base, timer);
@@ -316,8 +291,6 @@ int mod_timer(struct timer_list *timer, unsigned long expires)
{
BUG_ON(!timer->function);
- check_timer(timer);
-
/*
* This is a common optimization triggered by the
* networking code - if the timer is re-modified
@@ -348,8 +321,6 @@ int del_timer(struct timer_list *timer)
unsigned long flags;
int ret = 0;
- check_timer(timer);
-
if (timer_pending(timer)) {
base = lock_timer_base(timer, &flags);
if (timer_pending(timer)) {
@@ -412,8 +383,6 @@ out:
*/
int del_timer_sync(struct timer_list *timer)
{
- check_timer(timer);
-
for (;;) {
int ret = try_to_del_timer_sync(timer);
if (ret >= 0)
@@ -632,143 +601,118 @@ long time_next_adjust;
*/
static void second_overflow(void)
{
- long ltemp;
-
- /* Bump the maxerror field */
- time_maxerror += time_tolerance >> SHIFT_USEC;
- if ( time_maxerror > NTP_PHASE_LIMIT ) {
- time_maxerror = NTP_PHASE_LIMIT;
- time_status |= STA_UNSYNC;
- }
-
- /*
- * 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. The microtime() routine or
- * external clock driver will insure that reported time
- * is always monotonic. The ugly divides should be
- * replaced.
- */
- 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:
- if (xtime.tv_sec % 86400 == 0) {
- xtime.tv_sec--;
- wall_to_monotonic.tv_sec++;
- /* The timer interpolator will make time change gradually instead
- * of an immediate jump by one second.
- */
- time_interpolator_update(-NSEC_PER_SEC);
- time_state = TIME_OOP;
- clock_was_set();
- printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n");
+ long ltemp;
+
+ /* Bump the maxerror field */
+ time_maxerror += time_tolerance >> SHIFT_USEC;
+ if (time_maxerror > NTP_PHASE_LIMIT) {
+ time_maxerror = NTP_PHASE_LIMIT;
+ time_status |= STA_UNSYNC;
}
- break;
-
- case TIME_DEL:
- if ((xtime.tv_sec + 1) % 86400 == 0) {
- xtime.tv_sec++;
- wall_to_monotonic.tv_sec--;
- /* Use of time interpolator for a gradual change of time */
- time_interpolator_update(NSEC_PER_SEC);
- time_state = TIME_WAIT;
- clock_was_set();
- printk(KERN_NOTICE "Clock: deleting leap second 23:59:59 UTC\n");
+
+ /*
+ * 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. The microtime()
+ * routine or external clock driver will insure that reported time is
+ * always monotonic. The ugly divides should be replaced.
+ */
+ 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:
+ if (xtime.tv_sec % 86400 == 0) {
+ xtime.tv_sec--;
+ wall_to_monotonic.tv_sec++;
+ /*
+ * The timer interpolator will make time change
+ * gradually instead of an immediate jump by one second
+ */
+ time_interpolator_update(-NSEC_PER_SEC);
+ time_state = TIME_OOP;
+ clock_was_set();
+ printk(KERN_NOTICE "Clock: inserting leap second "
+ "23:59:60 UTC\n");
+ }
+ break;
+ case TIME_DEL:
+ if ((xtime.tv_sec + 1) % 86400 == 0) {
+ xtime.tv_sec++;
+ wall_to_monotonic.tv_sec--;
+ /*
+ * Use of time interpolator for a gradual change of
+ * time
+ */
+ time_interpolator_update(NSEC_PER_SEC);
+ time_state = TIME_WAIT;
+ clock_was_set();
+ printk(KERN_NOTICE "Clock: deleting leap second "
+ "23:59:59 UTC\n");
+ }
+ break;
+ case TIME_OOP:
+ time_state = TIME_WAIT;
+ break;
+ case TIME_WAIT:
+ if (!(time_status & (STA_INS | STA_DEL)))
+ time_state = TIME_OK;
}
- break;
-
- case TIME_OOP:
- time_state = TIME_WAIT;
- break;
-
- case TIME_WAIT:
- if (!(time_status & (STA_INS | STA_DEL)))
- time_state = TIME_OK;
- }
-
- /*
- * Compute the phase adjustment for the next second. In
- * PLL mode, the offset is reduced by a fixed factor
- * times the time constant. In FLL mode the offset is
- * used directly. In either mode, the maximum phase
- * adjustment for each second is clamped so as to spread
- * the adjustment over not more than the number of
- * seconds between updates.
- */
- if (time_offset < 0) {
- ltemp = -time_offset;
- if (!(time_status & STA_FLL))
- ltemp >>= SHIFT_KG + time_constant;
- if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
- ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
- time_offset += ltemp;
- time_adj = -ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
- } else {
+
+ /*
+ * Compute the phase adjustment for the next second. In PLL mode, the
+ * offset is reduced by a fixed factor times the time constant. In FLL
+ * mode the offset is used directly. In either mode, the maximum phase
+ * adjustment for each second is clamped so as to spread the adjustment
+ * over not more than the number of seconds between updates.
+ */
ltemp = time_offset;
if (!(time_status & STA_FLL))
- ltemp >>= SHIFT_KG + time_constant;
- if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
- ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
+ ltemp = shift_right(ltemp, SHIFT_KG + time_constant);
+ ltemp = min(ltemp, (MAXPHASE / MINSEC) << SHIFT_UPDATE);
+ ltemp = max(ltemp, -(MAXPHASE / MINSEC) << SHIFT_UPDATE);
time_offset -= ltemp;
time_adj = ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
- }
-
- /*
- * Compute the frequency estimate and additional phase
- * adjustment due to frequency error for the next
- * second. When the PPS signal is engaged, gnaw on the
- * watchdog counter and update the frequency computed by
- * the pll and the PPS signal.
- */
- pps_valid++;
- if (pps_valid == PPS_VALID) { /* PPS signal lost */
- pps_jitter = MAXTIME;
- pps_stabil = MAXFREQ;
- time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER |
- STA_PPSWANDER | STA_PPSERROR);
- }
- ltemp = time_freq + pps_freq;
- if (ltemp < 0)
- time_adj -= -ltemp >>
- (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
- else
- time_adj += ltemp >>
- (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
+
+ /*
+ * Compute the frequency estimate and additional phase adjustment due
+ * to frequency error for the next second. When the PPS signal is
+ * engaged, gnaw on the watchdog counter and update the frequency
+ * computed by the pll and the PPS signal.
+ */
+ pps_valid++;
+ if (pps_valid == PPS_VALID) { /* PPS signal lost */
+ pps_jitter = MAXTIME;
+ pps_stabil = MAXFREQ;
+ time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER |
+ STA_PPSWANDER | STA_PPSERROR);
+ }
+ ltemp = time_freq + pps_freq;
+ time_adj += shift_right(ltemp,(SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE));
#if HZ == 100
- /* Compensate for (HZ==100) != (1 << SHIFT_HZ).
- * Add 25% and 3.125% to get 128.125; => only 0.125% error (p. 14)
- */
- if (time_adj < 0)
- time_adj -= (-time_adj >> 2) + (-time_adj >> 5);
- else
- time_adj += (time_adj >> 2) + (time_adj >> 5);
+ /*
+ * Compensate for (HZ==100) != (1 << SHIFT_HZ). Add 25% and 3.125% to
+ * get 128.125; => only 0.125% error (p. 14)
+ */
+ time_adj += shift_right(time_adj, 2) + shift_right(time_adj, 5);
#endif
#if HZ == 250
- /* Compensate for (HZ==250) != (1 << SHIFT_HZ).
- * Add 1.5625% and 0.78125% to get 255.85938; => only 0.05% error (p. 14)
- */
- if (time_adj < 0)
- time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
- else
- time_adj += (time_adj >> 6) + (time_adj >> 7);
+ /*
+ * Compensate for (HZ==250) != (1 << SHIFT_HZ). Add 1.5625% and
+ * 0.78125% to get 255.85938; => only 0.05% error (p. 14)
+ */
+ time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7);
#endif
#if HZ == 1000
- /* Compensate for (HZ==1000) != (1 << SHIFT_HZ).
- * Add 1.5625% and 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
- */
- if (time_adj < 0)
- time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
- else
- time_adj += (time_adj >> 6) + (time_adj >> 7);
+ /*
+ * Compensate for (HZ==1000) != (1 << SHIFT_HZ). Add 1.5625% and
+ * 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
+ */
+ time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7);
#endif
}
@@ -777,23 +721,20 @@ static void update_wall_time_one_tick(void)
{
long time_adjust_step, delta_nsec;
- if ( (time_adjust_step = time_adjust) != 0 ) {
- /* We are doing an adjtime thing.
- *
- * Prepare time_adjust_step to be within bounds.
- * Note that a positive time_adjust means we want the clock
- * to run faster.
- *
- * Limit the amount of the step to be in the range
- * -tickadj .. +tickadj
- */
- if (time_adjust > tickadj)
- time_adjust_step = tickadj;
- else if (time_adjust < -tickadj)
- time_adjust_step = -tickadj;
-
- /* Reduce by this step the amount of time left */
- time_adjust -= time_adjust_step;
+ if ((time_adjust_step = time_adjust) != 0 ) {
+ /*
+ * We are doing an adjtime thing. Prepare time_adjust_step to
+ * be within bounds. Note that a positive time_adjust means we
+ * want the clock to run faster.
+ *
+ * Limit the amount of the step to be in the range
+ * -tickadj .. +tickadj
+ */
+ time_adjust_step = min(time_adjust_step, (long)tickadj);
+ time_adjust_step = max(time_adjust_step, (long)-tickadj);
+
+ /* Reduce by this step the amount of time left */
+ time_adjust -= time_adjust_step;
}
delta_nsec = tick_nsec + time_adjust_step * 1000;
/*
@@ -801,13 +742,8 @@ static void update_wall_time_one_tick(void)
* advance the tick more.
*/
time_phase += time_adj;
- if (time_phase <= -FINENSEC) {
- long ltemp = -time_phase >> (SHIFT_SCALE - 10);
- time_phase += ltemp << (SHIFT_SCALE - 10);
- delta_nsec -= ltemp;
- }
- else if (time_phase >= FINENSEC) {
- long ltemp = time_phase >> (SHIFT_SCALE - 10);
+ if ((time_phase >= FINENSEC) || (time_phase <= -FINENSEC)) {
+ long ltemp = shift_right(time_phase, (SHIFT_SCALE - 10));
time_phase -= ltemp << (SHIFT_SCALE - 10);
delta_nsec += ltemp;
}
@@ -1137,8 +1073,8 @@ fastcall signed long __sched schedule_timeout(signed long timeout)
if (timeout < 0)
{
printk(KERN_ERR "schedule_timeout: wrong timeout "
- "value %lx from %p\n", timeout,
- __builtin_return_address(0));
+ "value %lx from %p\n", timeout,
+ __builtin_return_address(0));
current->state = TASK_RUNNING;
goto out;
}
@@ -1146,12 +1082,8 @@ fastcall signed long __sched schedule_timeout(signed long timeout)
expire = timeout + jiffies;
- init_timer(&timer);
- timer.expires = expire;
- timer.data = (unsigned long) current;
- timer.function = process_timeout;
-
- add_timer(&timer);
+ setup_timer(&timer, process_timeout, (unsigned long)current);
+ __mod_timer(&timer, expire);
schedule();
del_singleshot_timer_sync(&timer);
@@ -1168,15 +1100,15 @@ EXPORT_SYMBOL(schedule_timeout);
*/
signed long __sched schedule_timeout_interruptible(signed long timeout)
{
- __set_current_state(TASK_INTERRUPTIBLE);
- return schedule_timeout(timeout);
+ __set_current_state(TASK_INTERRUPTIBLE);
+ return schedule_timeout(timeout);
}
EXPORT_SYMBOL(schedule_timeout_interruptible);
signed long __sched schedule_timeout_uninterruptible(signed long timeout)
{
- __set_current_state(TASK_UNINTERRUPTIBLE);
- return schedule_timeout(timeout);
+ __set_current_state(TASK_UNINTERRUPTIBLE);
+ return schedule_timeout(timeout);
}
EXPORT_SYMBOL(schedule_timeout_uninterruptible);
@@ -1516,16 +1448,18 @@ static void time_interpolator_update(long delta_nsec)
if (!time_interpolator)
return;
- /* The interpolator compensates for late ticks by accumulating
- * the late time in time_interpolator->offset. A tick earlier than
- * expected will lead to a reset of the offset and a corresponding
- * jump of the clock forward. Again this only works if the
- * interpolator clock is running slightly slower than the regular clock
- * and the tuning logic insures that.
- */
+ /*
+ * The interpolator compensates for late ticks by accumulating the late
+ * time in time_interpolator->offset. A tick earlier than expected will
+ * lead to a reset of the offset and a corresponding jump of the clock
+ * forward. Again this only works if the interpolator clock is running
+ * slightly slower than the regular clock and the tuning logic insures
+ * that.
+ */
counter = time_interpolator_get_counter(1);
- offset = time_interpolator->offset + GET_TI_NSECS(counter, time_interpolator);
+ offset = time_interpolator->offset +
+ GET_TI_NSECS(counter, time_interpolator);
if (delta_nsec < 0 || (unsigned long) delta_nsec < offset)
time_interpolator->offset = offset - delta_nsec;