/*
* linux/kernel/timer.c
*
- * Kernel internal timers, kernel timekeeping, basic process system calls
+ * Kernel internal timers, basic process system calls
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
#include <linux/cpu.h>
#include <linux/syscalls.h>
#include <linux/delay.h>
+#include <linux/tick.h>
+#include <linux/kallsyms.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
tvec_t tv3;
tvec_t tv4;
tvec_t tv5;
-} ____cacheline_aligned_in_smp;
+} ____cacheline_aligned;
typedef struct tvec_t_base_s tvec_base_t;
EXPORT_SYMBOL(boot_tvec_bases);
static DEFINE_PER_CPU(tvec_base_t *, tvec_bases) = &boot_tvec_bases;
+/*
+ * Note that all tvec_bases is 2 byte aligned and lower bit of
+ * base in timer_list is guaranteed to be zero. Use the LSB for
+ * the new flag to indicate whether the timer is deferrable
+ */
+#define TBASE_DEFERRABLE_FLAG (0x1)
+
+/* Functions below help us manage 'deferrable' flag */
+static inline unsigned int tbase_get_deferrable(tvec_base_t *base)
+{
+ return ((unsigned int)(unsigned long)base & TBASE_DEFERRABLE_FLAG);
+}
+
+static inline tvec_base_t *tbase_get_base(tvec_base_t *base)
+{
+ return ((tvec_base_t *)((unsigned long)base & ~TBASE_DEFERRABLE_FLAG));
+}
+
+static inline void timer_set_deferrable(struct timer_list *timer)
+{
+ timer->base = ((tvec_base_t *)((unsigned long)(timer->base) |
+ TBASE_DEFERRABLE_FLAG));
+}
+
+static inline void
+timer_set_base(struct timer_list *timer, tvec_base_t *new_base)
+{
+ timer->base = (tvec_base_t *)((unsigned long)(new_base) |
+ tbase_get_deferrable(timer->base));
+}
+
/**
* __round_jiffies - function to round jiffies to a full second
* @j: the time in (absolute) jiffies that should be rounded
* @cpu: the processor number on which the timeout will happen
*
- * __round_jiffies rounds an absolute time in the future (in jiffies)
+ * __round_jiffies() rounds an absolute time in the future (in jiffies)
* up or down to (approximately) full seconds. This is useful for timers
* for which the exact time they fire does not matter too much, as long as
* they fire approximately every X seconds.
* processors firing at the exact same time, which could lead
* to lock contention or spurious cache line bouncing.
*
- * The return value is the rounded version of the "j" parameter.
+ * The return value is the rounded version of the @j parameter.
*/
unsigned long __round_jiffies(unsigned long j, int cpu)
{
* @j: the time in (relative) jiffies that should be rounded
* @cpu: the processor number on which the timeout will happen
*
- * __round_jiffies_relative rounds a time delta in the future (in jiffies)
+ * __round_jiffies_relative() rounds a time delta in the future (in jiffies)
* up or down to (approximately) full seconds. This is useful for timers
* for which the exact time they fire does not matter too much, as long as
* they fire approximately every X seconds.
* processors firing at the exact same time, which could lead
* to lock contention or spurious cache line bouncing.
*
- * The return value is the rounded version of the "j" parameter.
+ * The return value is the rounded version of the @j parameter.
*/
unsigned long __round_jiffies_relative(unsigned long j, int cpu)
{
* round_jiffies - function to round jiffies to a full second
* @j: the time in (absolute) jiffies that should be rounded
*
- * round_jiffies rounds an absolute time in the future (in jiffies)
+ * round_jiffies() rounds an absolute time in the future (in jiffies)
* up or down to (approximately) full seconds. This is useful for timers
* for which the exact time they fire does not matter too much, as long as
* they fire approximately every X seconds.
* at the same time, rather than at various times spread out. The goal
* of this is to have the CPU wake up less, which saves power.
*
- * The return value is the rounded version of the "j" parameter.
+ * The return value is the rounded version of the @j parameter.
*/
unsigned long round_jiffies(unsigned long j)
{
* round_jiffies_relative - function to round jiffies to a full second
* @j: the time in (relative) jiffies that should be rounded
*
- * round_jiffies_relative rounds a time delta in the future (in jiffies)
+ * round_jiffies_relative() rounds a time delta in the future (in jiffies)
* up or down to (approximately) full seconds. This is useful for timers
* for which the exact time they fire does not matter too much, as long as
* they fire approximately every X seconds.
* at the same time, rather than at various times spread out. The goal
* of this is to have the CPU wake up less, which saves power.
*
- * The return value is the rounded version of the "j" parameter.
+ * The return value is the rounded version of the @j parameter.
*/
unsigned long round_jiffies_relative(unsigned long j)
{
list_add_tail(&timer->entry, vec);
}
+#ifdef CONFIG_TIMER_STATS
+void __timer_stats_timer_set_start_info(struct timer_list *timer, void *addr)
+{
+ if (timer->start_site)
+ return;
+
+ timer->start_site = addr;
+ memcpy(timer->start_comm, current->comm, TASK_COMM_LEN);
+ timer->start_pid = current->pid;
+}
+#endif
+
/**
* init_timer - initialize a timer.
* @timer: the timer to be initialized
{
timer->entry.next = NULL;
timer->base = __raw_get_cpu_var(tvec_bases);
+#ifdef CONFIG_TIMER_STATS
+ timer->start_site = NULL;
+ timer->start_pid = -1;
+ memset(timer->start_comm, 0, TASK_COMM_LEN);
+#endif
}
EXPORT_SYMBOL(init_timer);
+void fastcall init_timer_deferrable(struct timer_list *timer)
+{
+ init_timer(timer);
+ timer_set_deferrable(timer);
+}
+EXPORT_SYMBOL(init_timer_deferrable);
+
static inline void detach_timer(struct timer_list *timer,
- int clear_pending)
+ int clear_pending)
{
struct list_head *entry = &timer->entry;
tvec_base_t *base;
for (;;) {
- base = timer->base;
+ tvec_base_t *prelock_base = timer->base;
+ base = tbase_get_base(prelock_base);
if (likely(base != NULL)) {
spin_lock_irqsave(&base->lock, *flags);
- if (likely(base == timer->base))
+ if (likely(prelock_base == timer->base))
return base;
/* The timer has migrated to another CPU */
spin_unlock_irqrestore(&base->lock, *flags);
unsigned long flags;
int ret = 0;
+ timer_stats_timer_set_start_info(timer);
BUG_ON(!timer->function);
base = lock_timer_base(timer, &flags);
*/
if (likely(base->running_timer != timer)) {
/* See the comment in lock_timer_base() */
- timer->base = NULL;
+ timer_set_base(timer, NULL);
spin_unlock(&base->lock);
base = new_base;
spin_lock(&base->lock);
- timer->base = base;
+ timer_set_base(timer, base);
}
}
tvec_base_t *base = per_cpu(tvec_bases, cpu);
unsigned long flags;
+ timer_stats_timer_set_start_info(timer);
BUG_ON(timer_pending(timer) || !timer->function);
spin_lock_irqsave(&base->lock, flags);
- timer->base = base;
+ timer_set_base(timer, base);
internal_add_timer(base, timer);
spin_unlock_irqrestore(&base->lock, flags);
}
* @timer: the timer to be modified
* @expires: new timeout in jiffies
*
- * mod_timer is a more efficient way to update the expire field of an
+ * mod_timer() is a more efficient way to update the expire field of an
* active timer (if the timer is inactive it will be activated)
*
* mod_timer(timer, expires) is equivalent to:
{
BUG_ON(!timer->function);
+ timer_stats_timer_set_start_info(timer);
/*
* This is a common optimization triggered by the
* networking code - if the timer is re-modified
unsigned long flags;
int ret = 0;
+ timer_stats_timer_clear_start_info(timer);
if (timer_pending(timer)) {
base = lock_timer_base(timer, &flags);
if (timer_pending(timer)) {
return ret;
}
+EXPORT_SYMBOL(try_to_del_timer_sync);
+
/**
* del_timer_sync - deactivate a timer and wait for the handler to finish.
* @timer: the timer to be deactivated
* the timer it also makes sure the handler has finished executing on other
* CPUs.
*
- * Synchronization rules: callers must prevent restarting of the timer,
+ * Synchronization rules: Callers must prevent restarting of the timer,
* otherwise this function is meaningless. It must not be called from
* interrupt contexts. The caller must not hold locks which would prevent
* completion of the timer's handler. The timer's handler must not call
* don't have to detach them individually.
*/
list_for_each_entry_safe(timer, tmp, &tv_list, entry) {
- BUG_ON(timer->base != base);
+ BUG_ON(tbase_get_base(timer->base) != base);
internal_add_timer(base, timer);
}
void (*fn)(unsigned long);
unsigned long data;
- timer = list_entry(head->next,struct timer_list,entry);
+ timer = list_first_entry(head, struct timer_list,entry);
fn = timer->function;
data = timer->data;
+ timer_stats_account_timer(timer);
+
set_running_timer(base, timer);
detach_timer(timer, 1);
spin_unlock_irq(&base->lock);
spin_unlock_irq(&base->lock);
}
-#ifdef CONFIG_NO_IDLE_HZ
+#if defined(CONFIG_NO_IDLE_HZ) || defined(CONFIG_NO_HZ)
/*
* Find out when the next timer event is due to happen. This
* is used on S/390 to stop all activity when a cpus is idle.
* This functions needs to be called disabled.
*/
-unsigned long next_timer_interrupt(void)
+static unsigned long __next_timer_interrupt(tvec_base_t *base)
{
- tvec_base_t *base;
- struct list_head *list;
+ unsigned long timer_jiffies = base->timer_jiffies;
+ unsigned long expires = timer_jiffies + NEXT_TIMER_MAX_DELTA;
+ int index, slot, array, found = 0;
struct timer_list *nte;
- unsigned long expires;
- unsigned long hr_expires = MAX_JIFFY_OFFSET;
- ktime_t hr_delta;
tvec_t *varray[4];
- int i, j;
-
- hr_delta = hrtimer_get_next_event();
- if (hr_delta.tv64 != KTIME_MAX) {
- struct timespec tsdelta;
- tsdelta = ktime_to_timespec(hr_delta);
- hr_expires = timespec_to_jiffies(&tsdelta);
- if (hr_expires < 3)
- return hr_expires + jiffies;
- }
- hr_expires += jiffies;
-
- base = __get_cpu_var(tvec_bases);
- spin_lock(&base->lock);
- expires = base->timer_jiffies + (LONG_MAX >> 1);
- list = NULL;
/* Look for timer events in tv1. */
- j = base->timer_jiffies & TVR_MASK;
+ index = slot = timer_jiffies & TVR_MASK;
do {
- list_for_each_entry(nte, base->tv1.vec + j, entry) {
+ list_for_each_entry(nte, base->tv1.vec + slot, entry) {
+ if (tbase_get_deferrable(nte->base))
+ continue;
+
+ found = 1;
expires = nte->expires;
- if (j < (base->timer_jiffies & TVR_MASK))
- list = base->tv2.vec + (INDEX(0));
- goto found;
+ /* Look at the cascade bucket(s)? */
+ if (!index || slot < index)
+ goto cascade;
+ return expires;
}
- j = (j + 1) & TVR_MASK;
- } while (j != (base->timer_jiffies & TVR_MASK));
+ slot = (slot + 1) & TVR_MASK;
+ } while (slot != index);
+
+cascade:
+ /* Calculate the next cascade event */
+ if (index)
+ timer_jiffies += TVR_SIZE - index;
+ timer_jiffies >>= TVR_BITS;
/* Check tv2-tv5. */
varray[0] = &base->tv2;
varray[1] = &base->tv3;
varray[2] = &base->tv4;
varray[3] = &base->tv5;
- for (i = 0; i < 4; i++) {
- j = INDEX(i);
+
+ for (array = 0; array < 4; array++) {
+ tvec_t *varp = varray[array];
+
+ index = slot = timer_jiffies & TVN_MASK;
do {
- if (list_empty(varray[i]->vec + j)) {
- j = (j + 1) & TVN_MASK;
- continue;
- }
- list_for_each_entry(nte, varray[i]->vec + j, entry)
+ list_for_each_entry(nte, varp->vec + slot, entry) {
+ found = 1;
if (time_before(nte->expires, expires))
expires = nte->expires;
- if (j < (INDEX(i)) && i < 3)
- list = varray[i + 1]->vec + (INDEX(i + 1));
- goto found;
- } while (j != (INDEX(i)));
- }
-found:
- if (list) {
- /*
- * The search wrapped. We need to look at the next list
- * from next tv element that would cascade into tv element
- * where we found the timer element.
- */
- list_for_each_entry(nte, list, entry) {
- if (time_before(nte->expires, expires))
- expires = nte->expires;
- }
- }
- spin_unlock(&base->lock);
-
- /*
- * It can happen that other CPUs service timer IRQs and increment
- * jiffies, but we have not yet got a local timer tick to process
- * the timer wheels. In that case, the expiry time can be before
- * jiffies, but since the high-resolution timer here is relative to
- * jiffies, the default expression when high-resolution timers are
- * not active,
- *
- * time_before(MAX_JIFFY_OFFSET + jiffies, expires)
- *
- * would falsely evaluate to true. If that is the case, just
- * return jiffies so that we can immediately fire the local timer
- */
- if (time_before(expires, jiffies))
- return jiffies;
-
- if (time_before(hr_expires, expires))
- return hr_expires;
-
- return expires;
-}
-#endif
-
-/******************************************************************/
-
-/*
- * 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.
- */
-struct timespec xtime __attribute__ ((aligned (16)));
-struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
-
-EXPORT_SYMBOL(xtime);
-
-
-/* XXX - all of this timekeeping code should be later moved to time.c */
-#include <linux/clocksource.h>
-static struct clocksource *clock; /* pointer to current clocksource */
-
-#ifdef CONFIG_GENERIC_TIME
-/**
- * __get_nsec_offset - Returns nanoseconds since last call to periodic_hook
- *
- * private function, must hold xtime_lock lock when being
- * called. Returns the number of nanoseconds since the
- * last call to update_wall_time() (adjusted by NTP scaling)
- */
-static inline s64 __get_nsec_offset(void)
-{
- cycle_t cycle_now, cycle_delta;
- s64 ns_offset;
-
- /* read clocksource: */
- cycle_now = clocksource_read(clock);
-
- /* calculate the delta since the last update_wall_time: */
- cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
-
- /* convert to nanoseconds: */
- ns_offset = cyc2ns(clock, cycle_delta);
-
- return ns_offset;
-}
-
-/**
- * __get_realtime_clock_ts - Returns the time of day in a timespec
- * @ts: pointer to the timespec to be set
- *
- * Returns the time of day in a timespec. Used by
- * do_gettimeofday() and get_realtime_clock_ts().
- */
-static inline void __get_realtime_clock_ts(struct timespec *ts)
-{
- unsigned long seq;
- s64 nsecs;
-
- do {
- seq = read_seqbegin(&xtime_lock);
-
- *ts = xtime;
- nsecs = __get_nsec_offset();
-
- } while (read_seqretry(&xtime_lock, seq));
-
- timespec_add_ns(ts, nsecs);
-}
-
-/**
- * getnstimeofday - Returns the time of day in a timespec
- * @ts: pointer to the timespec to be set
- *
- * Returns the time of day in a timespec.
- */
-void getnstimeofday(struct timespec *ts)
-{
- __get_realtime_clock_ts(ts);
-}
-
-EXPORT_SYMBOL(getnstimeofday);
-
-/**
- * do_gettimeofday - Returns the time of day in a timeval
- * @tv: pointer to the timeval to be set
- *
- * NOTE: Users should be converted to using get_realtime_clock_ts()
- */
-void do_gettimeofday(struct timeval *tv)
-{
- struct timespec now;
-
- __get_realtime_clock_ts(&now);
- tv->tv_sec = now.tv_sec;
- tv->tv_usec = now.tv_nsec/1000;
-}
-
-EXPORT_SYMBOL(do_gettimeofday);
-/**
- * do_settimeofday - Sets the time of day
- * @tv: pointer to the timespec variable containing the new time
- *
- * Sets the time of day to the new time and update NTP and notify hrtimers
- */
-int do_settimeofday(struct timespec *tv)
-{
- unsigned long flags;
- time_t wtm_sec, sec = tv->tv_sec;
- long wtm_nsec, nsec = tv->tv_nsec;
-
- if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
- return -EINVAL;
-
- write_seqlock_irqsave(&xtime_lock, flags);
-
- nsec -= __get_nsec_offset();
-
- wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
- wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
-
- set_normalized_timespec(&xtime, sec, nsec);
- set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
-
- clock->error = 0;
- ntp_clear();
-
- write_sequnlock_irqrestore(&xtime_lock, flags);
-
- /* signal hrtimers about time change */
- clock_was_set();
-
- return 0;
-}
-
-EXPORT_SYMBOL(do_settimeofday);
+ }
+ /*
+ * Do we still search for the first timer or are
+ * we looking up the cascade buckets ?
+ */
+ if (found) {
+ /* Look at the cascade bucket(s)? */
+ if (!index || slot < index)
+ break;
+ return expires;
+ }
+ slot = (slot + 1) & TVN_MASK;
+ } while (slot != index);
-/**
- * change_clocksource - Swaps clocksources if a new one is available
- *
- * Accumulates current time interval and initializes new clocksource
- */
-static int change_clocksource(void)
-{
- struct clocksource *new;
- cycle_t now;
- u64 nsec;
- new = clocksource_get_next();
- if (clock != new) {
- now = clocksource_read(new);
- nsec = __get_nsec_offset();
- timespec_add_ns(&xtime, nsec);
-
- clock = new;
- clock->cycle_last = now;
- printk(KERN_INFO "Time: %s clocksource has been installed.\n",
- clock->name);
- return 1;
- } else if (clock->update_callback) {
- return clock->update_callback();
+ if (index)
+ timer_jiffies += TVN_SIZE - index;
+ timer_jiffies >>= TVN_BITS;
}
- return 0;
-}
-#else
-static inline int change_clocksource(void)
-{
- return 0;
-}
-#endif
-
-/**
- * timeofday_is_continuous - check to see if timekeeping is free running
- */
-int timekeeping_is_continuous(void)
-{
- unsigned long seq;
- int ret;
-
- do {
- seq = read_seqbegin(&xtime_lock);
-
- ret = clock->is_continuous;
-
- } while (read_seqretry(&xtime_lock, seq));
-
- return ret;
+ return expires;
}
/*
- * timekeeping_init - Initializes the clocksource and common timekeeping values
+ * Check, if the next hrtimer event is before the next timer wheel
+ * event:
*/
-void __init timekeeping_init(void)
+static unsigned long cmp_next_hrtimer_event(unsigned long now,
+ unsigned long expires)
{
- unsigned long flags;
+ ktime_t hr_delta = hrtimer_get_next_event();
+ struct timespec tsdelta;
+ unsigned long delta;
- write_seqlock_irqsave(&xtime_lock, flags);
+ if (hr_delta.tv64 == KTIME_MAX)
+ return expires;
- ntp_clear();
-
- clock = clocksource_get_next();
- clocksource_calculate_interval(clock, tick_nsec);
- clock->cycle_last = clocksource_read(clock);
-
- write_sequnlock_irqrestore(&xtime_lock, flags);
-}
-
-
-static int timekeeping_suspended;
-/**
- * timekeeping_resume - Resumes the generic timekeeping subsystem.
- * @dev: unused
- *
- * This is for the generic clocksource timekeeping.
- * xtime/wall_to_monotonic/jiffies/etc are
- * still managed by arch specific suspend/resume code.
- */
-static int timekeeping_resume(struct sys_device *dev)
-{
- unsigned long flags;
-
- write_seqlock_irqsave(&xtime_lock, flags);
- /* restart the last cycle value */
- clock->cycle_last = clocksource_read(clock);
- clock->error = 0;
- timekeeping_suspended = 0;
- write_sequnlock_irqrestore(&xtime_lock, flags);
- return 0;
-}
-
-static int timekeeping_suspend(struct sys_device *dev, pm_message_t state)
-{
- unsigned long flags;
-
- write_seqlock_irqsave(&xtime_lock, flags);
- timekeeping_suspended = 1;
- write_sequnlock_irqrestore(&xtime_lock, flags);
- return 0;
-}
-
-/* sysfs resume/suspend bits for timekeeping */
-static struct sysdev_class timekeeping_sysclass = {
- .resume = timekeeping_resume,
- .suspend = timekeeping_suspend,
- set_kset_name("timekeeping"),
-};
-
-static struct sys_device device_timer = {
- .id = 0,
- .cls = &timekeeping_sysclass,
-};
-
-static int __init timekeeping_init_device(void)
-{
- int error = sysdev_class_register(&timekeeping_sysclass);
- if (!error)
- error = sysdev_register(&device_timer);
- return error;
-}
-
-device_initcall(timekeeping_init_device);
+ /*
+ * Expired timer available, let it expire in the next tick
+ */
+ if (hr_delta.tv64 <= 0)
+ return now + 1;
-/*
- * If the error is already larger, we look ahead even further
- * to compensate for late or lost adjustments.
- */
-static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
- s64 *offset)
-{
- s64 tick_error, i;
- u32 look_ahead, adj;
- s32 error2, mult;
+ tsdelta = ktime_to_timespec(hr_delta);
+ delta = timespec_to_jiffies(&tsdelta);
/*
- * Use the current error value to determine how much to look ahead.
- * The larger the error the slower we adjust for it to avoid problems
- * with losing too many ticks, otherwise we would overadjust and
- * produce an even larger error. The smaller the adjustment the
- * faster we try to adjust for it, as lost ticks can do less harm
- * here. This is tuned so that an error of about 1 msec is adusted
- * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks).
+ * Limit the delta to the max value, which is checked in
+ * tick_nohz_stop_sched_tick():
*/
- error2 = clock->error >> (TICK_LENGTH_SHIFT + 22 - 2 * SHIFT_HZ);
- error2 = abs(error2);
- for (look_ahead = 0; error2 > 0; look_ahead++)
- error2 >>= 2;
+ if (delta > NEXT_TIMER_MAX_DELTA)
+ delta = NEXT_TIMER_MAX_DELTA;
/*
- * Now calculate the error in (1 << look_ahead) ticks, but first
- * remove the single look ahead already included in the error.
+ * Take rounding errors in to account and make sure, that it
+ * expires in the next tick. Otherwise we go into an endless
+ * ping pong due to tick_nohz_stop_sched_tick() retriggering
+ * the timer softirq
*/
- tick_error = current_tick_length() >>
- (TICK_LENGTH_SHIFT - clock->shift + 1);
- tick_error -= clock->xtime_interval >> 1;
- error = ((error - tick_error) >> look_ahead) + tick_error;
-
- /* Finally calculate the adjustment shift value. */
- i = *interval;
- mult = 1;
- if (error < 0) {
- error = -error;
- *interval = -*interval;
- *offset = -*offset;
- mult = -1;
- }
- for (adj = 0; error > i; adj++)
- error >>= 1;
-
- *interval <<= adj;
- *offset <<= adj;
- return mult << adj;
-}
-
-/*
- * Adjust the multiplier to reduce the error value,
- * this is optimized for the most common adjustments of -1,0,1,
- * for other values we can do a bit more work.
- */
-static void clocksource_adjust(struct clocksource *clock, s64 offset)
-{
- s64 error, interval = clock->cycle_interval;
- int adj;
-
- error = clock->error >> (TICK_LENGTH_SHIFT - clock->shift - 1);
- if (error > interval) {
- error >>= 2;
- if (likely(error <= interval))
- adj = 1;
- else
- adj = clocksource_bigadjust(error, &interval, &offset);
- } else if (error < -interval) {
- error >>= 2;
- if (likely(error >= -interval)) {
- adj = -1;
- interval = -interval;
- offset = -offset;
- } else
- adj = clocksource_bigadjust(error, &interval, &offset);
- } else
- return;
-
- clock->mult += adj;
- clock->xtime_interval += interval;
- clock->xtime_nsec -= offset;
- clock->error -= (interval - offset) <<
- (TICK_LENGTH_SHIFT - clock->shift);
+ if (delta < 1)
+ delta = 1;
+ now += delta;
+ if (time_before(now, expires))
+ return now;
+ return expires;
}
/**
- * update_wall_time - Uses the current clocksource to increment the wall time
- *
- * Called from the timer interrupt, must hold a write on xtime_lock.
+ * next_timer_interrupt - return the jiffy of the next pending timer
+ * @now: current time (in jiffies)
*/
-static void update_wall_time(void)
+unsigned long get_next_timer_interrupt(unsigned long now)
{
- cycle_t offset;
-
- /* Make sure we're fully resumed: */
- if (unlikely(timekeeping_suspended))
- return;
-
-#ifdef CONFIG_GENERIC_TIME
- offset = (clocksource_read(clock) - clock->cycle_last) & clock->mask;
-#else
- offset = clock->cycle_interval;
-#endif
- clock->xtime_nsec += (s64)xtime.tv_nsec << clock->shift;
-
- /* normally this loop will run just once, however in the
- * case of lost or late ticks, it will accumulate correctly.
- */
- while (offset >= clock->cycle_interval) {
- /* accumulate one interval */
- clock->xtime_nsec += clock->xtime_interval;
- clock->cycle_last += clock->cycle_interval;
- offset -= clock->cycle_interval;
-
- if (clock->xtime_nsec >= (u64)NSEC_PER_SEC << clock->shift) {
- clock->xtime_nsec -= (u64)NSEC_PER_SEC << clock->shift;
- xtime.tv_sec++;
- second_overflow();
- }
-
- /* interpolator bits */
- time_interpolator_update(clock->xtime_interval
- >> clock->shift);
+ tvec_base_t *base = __get_cpu_var(tvec_bases);
+ unsigned long expires;
- /* accumulate error between NTP and clock interval */
- clock->error += current_tick_length();
- clock->error -= clock->xtime_interval << (TICK_LENGTH_SHIFT - clock->shift);
- }
+ spin_lock(&base->lock);
+ expires = __next_timer_interrupt(base);
+ spin_unlock(&base->lock);
- /* correct the clock when NTP error is too big */
- clocksource_adjust(clock, offset);
+ if (time_before_eq(expires, now))
+ return now;
- /* store full nanoseconds into xtime */
- xtime.tv_nsec = (s64)clock->xtime_nsec >> clock->shift;
- clock->xtime_nsec -= (s64)xtime.tv_nsec << clock->shift;
+ return cmp_next_hrtimer_event(now, expires);
+}
- /* check to see if there is a new clocksource to use */
- if (change_clocksource()) {
- clock->error = 0;
- clock->xtime_nsec = 0;
- clocksource_calculate_interval(clock, tick_nsec);
- }
+#ifdef CONFIG_NO_IDLE_HZ
+unsigned long next_timer_interrupt(void)
+{
+ return get_next_timer_interrupt(jiffies);
}
+#endif
+
+#endif
/*
* Called from the timer interrupt handler to charge one tick to the current
}
/*
- * This read-write spinlock protects us from races in SMP while
- * playing with xtime and avenrun.
- */
-#ifndef ARCH_HAVE_XTIME_LOCK
-__cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
-
-EXPORT_SYMBOL(xtime_lock);
-#endif
-
-/*
* This function runs timers and the timer-tq in bottom half context.
*/
static void run_timer_softirq(struct softirq_action *h)
{
tvec_base_t *base = __get_cpu_var(tvec_bases);
- hrtimer_run_queues();
+ hrtimer_run_queues();
+
if (time_after_eq(jiffies, base->timer_jiffies))
__run_timers(base);
}
* should never happens anyway). You just have the printk()
* that will tell you if something is gone wrong and where.
*/
- if (timeout < 0)
- {
+ if (timeout < 0) {
printk(KERN_ERR "schedule_timeout: wrong timeout "
- "value %lx from %p\n", timeout,
- __builtin_return_address(0));
+ "value %lx\n", timeout);
+ dump_stack();
current->state = TASK_RUNNING;
goto out;
}
}
/**
- * sys_sysinfo - fill in sysinfo struct
+ * do_sysinfo - fill in sysinfo struct
* @info: pointer to buffer to fill
*/
-asmlinkage long sys_sysinfo(struct sysinfo __user *info)
+int do_sysinfo(struct sysinfo *info)
{
- struct sysinfo val;
unsigned long mem_total, sav_total;
unsigned int mem_unit, bitcount;
unsigned long seq;
- memset((char *)&val, 0, sizeof(struct sysinfo));
+ memset(info, 0, sizeof(struct sysinfo));
do {
struct timespec tp;
tp.tv_nsec = tp.tv_nsec - NSEC_PER_SEC;
tp.tv_sec++;
}
- val.uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
+ info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
- val.loads[0] = avenrun[0] << (SI_LOAD_SHIFT - FSHIFT);
- val.loads[1] = avenrun[1] << (SI_LOAD_SHIFT - FSHIFT);
- val.loads[2] = avenrun[2] << (SI_LOAD_SHIFT - FSHIFT);
+ info->loads[0] = avenrun[0] << (SI_LOAD_SHIFT - FSHIFT);
+ info->loads[1] = avenrun[1] << (SI_LOAD_SHIFT - FSHIFT);
+ info->loads[2] = avenrun[2] << (SI_LOAD_SHIFT - FSHIFT);
- val.procs = nr_threads;
+ info->procs = nr_threads;
} while (read_seqretry(&xtime_lock, seq));
- si_meminfo(&val);
- si_swapinfo(&val);
+ si_meminfo(info);
+ si_swapinfo(info);
/*
* If the sum of all the available memory (i.e. ram + swap)
* -Erik Andersen <andersee@debian.org>
*/
- mem_total = val.totalram + val.totalswap;
- if (mem_total < val.totalram || mem_total < val.totalswap)
+ mem_total = info->totalram + info->totalswap;
+ if (mem_total < info->totalram || mem_total < info->totalswap)
goto out;
bitcount = 0;
- mem_unit = val.mem_unit;
+ mem_unit = info->mem_unit;
while (mem_unit > 1) {
bitcount++;
mem_unit >>= 1;
/*
* If mem_total did not overflow, multiply all memory values by
- * val.mem_unit and set it to 1. This leaves things compatible
+ * info->mem_unit and set it to 1. This leaves things compatible
* with 2.2.x, and also retains compatibility with earlier 2.4.x
* kernels...
*/
- val.mem_unit = 1;
- val.totalram <<= bitcount;
- val.freeram <<= bitcount;
- val.sharedram <<= bitcount;
- val.bufferram <<= bitcount;
- val.totalswap <<= bitcount;
- val.freeswap <<= bitcount;
- val.totalhigh <<= bitcount;
- val.freehigh <<= bitcount;
+ info->mem_unit = 1;
+ info->totalram <<= bitcount;
+ info->freeram <<= bitcount;
+ info->sharedram <<= bitcount;
+ info->bufferram <<= bitcount;
+ info->totalswap <<= bitcount;
+ info->freeswap <<= bitcount;
+ info->totalhigh <<= bitcount;
+ info->freehigh <<= bitcount;
+
+out:
+ return 0;
+}
+
+asmlinkage long sys_sysinfo(struct sysinfo __user *info)
+{
+ struct sysinfo val;
+
+ do_sysinfo(&val);
- out:
if (copy_to_user(info, &val, sizeof(struct sysinfo)))
return -EFAULT;
cpu_to_node(cpu));
if (!base)
return -ENOMEM;
+
+ /* Make sure that tvec_base is 2 byte aligned */
+ if (tbase_get_deferrable(base)) {
+ WARN_ON(1);
+ kfree(base);
+ return -ENOMEM;
+ }
memset(base, 0, sizeof(*base));
per_cpu(tvec_bases, cpu) = base;
} else {
struct timer_list *timer;
while (!list_empty(head)) {
- timer = list_entry(head->next, struct timer_list, entry);
+ timer = list_first_entry(head, struct timer_list, entry);
detach_timer(timer, 0);
- timer->base = new_base;
+ timer_set_base(timer, new_base);
internal_add_timer(new_base, timer);
}
}
new_base = get_cpu_var(tvec_bases);
local_irq_disable();
- spin_lock(&new_base->lock);
- spin_lock(&old_base->lock);
+ double_spin_lock(&new_base->lock, &old_base->lock,
+ smp_processor_id() < cpu);
BUG_ON(old_base->running_timer);
migrate_timer_list(new_base, old_base->tv5.vec + i);
}
- spin_unlock(&old_base->lock);
- spin_unlock(&new_base->lock);
+ double_spin_unlock(&new_base->lock, &old_base->lock,
+ smp_processor_id() < cpu);
local_irq_enable();
put_cpu_var(tvec_bases);
}
long cpu = (long)hcpu;
switch(action) {
case CPU_UP_PREPARE:
+ case CPU_UP_PREPARE_FROZEN:
if (init_timers_cpu(cpu) < 0)
return NOTIFY_BAD;
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
migrate_timers(cpu);
break;
#endif
int err = timer_cpu_notify(&timers_nb, (unsigned long)CPU_UP_PREPARE,
(void *)(long)smp_processor_id());
+ init_timer_stats();
+
BUG_ON(err == NOTIFY_BAD);
register_cpu_notifier(&timers_nb);
open_softirq(TIMER_SOFTIRQ, run_timer_softirq, NULL);
static struct time_interpolator *time_interpolator_list __read_mostly;
static DEFINE_SPINLOCK(time_interpolator_lock);
-static inline u64 time_interpolator_get_cycles(unsigned int src)
+static inline cycles_t time_interpolator_get_cycles(unsigned int src)
{
unsigned long (*x)(void);
if (time_interpolator->jitter)
{
- u64 lcycle;
- u64 now;
+ cycles_t lcycle;
+ cycles_t now;
do {
lcycle = time_interpolator->last_cycle;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff