* Credits:
* based on kernel/timer.c
*
+ * Help, testing, suggestions, bugfixes, improvements were
+ * provided by:
+ *
+ * George Anzinger, Andrew Morton, Steven Rostedt, Roman Zippel
+ * et. al.
+ *
* For licencing details see kernel-base/COPYING
*/
/*
* The timer bases:
+ *
+ * Note: If we want to add new timer bases, we have to skip the two
+ * clock ids captured by the cpu-timers. We do this by holding empty
+ * entries rather than doing math adjustment of the clock ids.
+ * This ensures that we capture erroneous accesses to these clock ids
+ * rather than moving them into the range of valid clock id's.
*/
#define MAX_HRTIMER_BASES 2
set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
ts->tv_nsec + tomono.tv_nsec);
}
+EXPORT_SYMBOL_GPL(ktime_get_ts);
/*
* Functions and macros which are different for UP/SMP systems are kept in a
* @interval: the interval to forward
*
* Forward the timer expiry so it will expire in the future.
- * The number of overruns is added to the overrun field.
+ * Returns the number of overruns.
*/
unsigned long
-hrtimer_forward(struct hrtimer *timer, const ktime_t interval)
+hrtimer_forward(struct hrtimer *timer, ktime_t interval)
{
unsigned long orun = 1;
ktime_t delta, now;
if (delta.tv64 < 0)
return 0;
+ if (interval.tv64 < timer->base->resolution.tv64)
+ interval.tv64 = timer->base->resolution.tv64;
+
if (unlikely(delta.tv64 >= interval.tv64)) {
nsec_t incr = ktime_to_ns(interval);
static void enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
{
struct rb_node **link = &base->active.rb_node;
- struct list_head *prev = &base->pending;
struct rb_node *parent = NULL;
struct hrtimer *entry;
*/
if (timer->expires.tv64 < entry->expires.tv64)
link = &(*link)->rb_left;
- else {
+ else
link = &(*link)->rb_right;
- prev = &entry->list;
- }
}
/*
- * Insert the timer to the rbtree and to the sorted list:
+ * Insert the timer to the rbtree and check whether it
+ * replaces the first pending timer
*/
rb_link_node(&timer->node, parent, link);
rb_insert_color(&timer->node, &base->active);
- list_add(&timer->list, prev);
timer->state = HRTIMER_PENDING;
-}
+ if (!base->first || timer->expires.tv64 <
+ rb_entry(base->first, struct hrtimer, node)->expires.tv64)
+ base->first = &timer->node;
+}
/*
* __remove_hrtimer - internal function to remove a timer
static void __remove_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
{
/*
- * Remove the timer from the sorted list and from the rbtree:
+ * Remove the timer from the rbtree and replace the
+ * first entry pointer if necessary.
*/
- list_del(&timer->list);
+ if (base->first == &timer->node)
+ base->first = rb_next(&timer->node);
rb_erase(&timer->node, &base->active);
}
/* Switch the timer base, if necessary: */
new_base = switch_hrtimer_base(timer, base);
- if (mode == HRTIMER_REL)
+ if (mode == HRTIMER_REL) {
tim = ktime_add(tim, new_base->get_time());
+ /*
+ * CONFIG_TIME_LOW_RES is a temporary way for architectures
+ * to signal that they simply return xtime in
+ * do_gettimeoffset(). In this case we want to round up by
+ * resolution when starting a relative timer, to avoid short
+ * timeouts. This will go away with the GTOD framework.
+ */
+#ifdef CONFIG_TIME_LOW_RES
+ tim = ktime_add(tim, base->resolution);
+#endif
+ }
timer->expires = tim;
enqueue_hrtimer(timer, new_base);
}
/**
- * hrtimer_rebase - rebase an initialized hrtimer to a different base
+ * hrtimer_init - initialize a timer to the given clock
*
- * @timer: the timer to be rebased
+ * @timer: the timer to be initialized
* @clock_id: the clock to be used
+ * @mode: timer mode abs/rel
*/
-void hrtimer_rebase(struct hrtimer *timer, const clockid_t clock_id)
+void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
+ enum hrtimer_mode mode)
{
struct hrtimer_base *bases;
+ memset(timer, 0, sizeof(struct hrtimer));
+
bases = per_cpu(hrtimer_bases, raw_smp_processor_id());
- timer->base = &bases[clock_id];
-}
-/**
- * hrtimer_init - initialize a timer to the given clock
- *
- * @timer: the timer to be initialized
- * @clock_id: the clock to be used
- */
-void hrtimer_init(struct hrtimer *timer, const clockid_t clock_id)
-{
- memset(timer, 0, sizeof(struct hrtimer));
- hrtimer_rebase(timer, clock_id);
+ if (clock_id == CLOCK_REALTIME && mode != HRTIMER_ABS)
+ clock_id = CLOCK_MONOTONIC;
+
+ timer->base = &bases[clock_id];
}
/**
{
struct hrtimer_base *bases;
- tp->tv_sec = 0;
bases = per_cpu(hrtimer_bases, raw_smp_processor_id());
- tp->tv_nsec = bases[which_clock].resolution;
+ *tp = ktime_to_timespec(bases[which_clock].resolution);
return 0;
}
static inline void run_hrtimer_queue(struct hrtimer_base *base)
{
ktime_t now = base->get_time();
+ struct rb_node *node;
spin_lock_irq(&base->lock);
- while (!list_empty(&base->pending)) {
+ while ((node = base->first)) {
struct hrtimer *timer;
int (*fn)(void *);
int restart;
void *data;
- timer = list_entry(base->pending.next, struct hrtimer, list);
+ timer = rb_entry(node, struct hrtimer, node);
if (now.tv64 <= timer->expires.tv64)
break;
fn = timer->function;
data = timer->data;
set_curr_timer(base, timer);
+ timer->state = HRTIMER_RUNNING;
__remove_hrtimer(timer, base);
spin_unlock_irq(&base->lock);
spin_lock_irq(&base->lock);
+ /* Another CPU has added back the timer */
+ if (timer->state != HRTIMER_RUNNING)
+ continue;
+
if (restart == HRTIMER_RESTART)
enqueue_hrtimer(timer, base);
else
return schedule_hrtimer(timer, mode);
}
-static long __sched
-nanosleep_restart(struct restart_block *restart, clockid_t clockid)
+static long __sched nanosleep_restart(struct restart_block *restart)
{
- struct timespec __user *rmtp, tu;
+ struct timespec __user *rmtp;
+ struct timespec tu;
void *rfn_save = restart->fn;
struct hrtimer timer;
ktime_t rem;
restart->fn = do_no_restart_syscall;
- hrtimer_init(&timer, clockid);
+ hrtimer_init(&timer, (clockid_t) restart->arg3, HRTIMER_ABS);
timer.expires.tv64 = ((u64)restart->arg1 << 32) | (u64) restart->arg0;
return -ERESTART_RESTARTBLOCK;
}
-static long __sched nanosleep_restart_mono(struct restart_block *restart)
-{
- return nanosleep_restart(restart, CLOCK_MONOTONIC);
-}
-
-static long __sched nanosleep_restart_real(struct restart_block *restart)
-{
- return nanosleep_restart(restart, CLOCK_REALTIME);
-}
-
long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
const enum hrtimer_mode mode, const clockid_t clockid)
{
struct timespec tu;
ktime_t rem;
- hrtimer_init(&timer, clockid);
+ hrtimer_init(&timer, clockid, mode);
timer.expires = timespec_to_ktime(*rqtp);
if (rem.tv64 <= 0)
return 0;
- /* Absolute timers do not update the rmtp value: */
+ /* Absolute timers do not update the rmtp value and restart: */
if (mode == HRTIMER_ABS)
return -ERESTARTNOHAND;
return -EFAULT;
restart = ¤t_thread_info()->restart_block;
- restart->fn = (clockid == CLOCK_MONOTONIC) ?
- nanosleep_restart_mono : nanosleep_restart_real;
+ restart->fn = nanosleep_restart;
restart->arg0 = timer.expires.tv64 & 0xFFFFFFFF;
restart->arg1 = timer.expires.tv64 >> 32;
restart->arg2 = (unsigned long) rmtp;
+ restart->arg3 = (unsigned long) timer.base->index;
return -ERESTART_RESTARTBLOCK;
}
struct hrtimer_base *base = per_cpu(hrtimer_bases, cpu);
int i;
- for (i = 0; i < MAX_HRTIMER_BASES; i++) {
+ for (i = 0; i < MAX_HRTIMER_BASES; i++, base++)
spin_lock_init(&base->lock);
- INIT_LIST_HEAD(&base->pending);
- base++;
- }
}
#ifdef CONFIG_HOTPLUG_CPU