--- /dev/null
+/*
+ * linux/kernel/hrtimer.c
+ *
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2005, Red Hat, Inc., Ingo Molnar
+ *
+ * High-resolution kernel timers
+ *
+ * In contrast to the low-resolution timeout API implemented in
+ * kernel/timer.c, hrtimers provide finer resolution and accuracy
+ * depending on system configuration and capabilities.
+ *
+ * These timers are currently used for:
+ * - itimers
+ * - POSIX timers
+ * - nanosleep
+ * - precise in-kernel timing
+ *
+ * Started by: Thomas Gleixner and Ingo Molnar
+ *
+ * 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
+ */
+
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/percpu.h>
+#include <linux/hrtimer.h>
+#include <linux/notifier.h>
+#include <linux/syscalls.h>
+#include <linux/interrupt.h>
+
+#include <asm/uaccess.h>
+
+/**
+ * ktime_get - get the monotonic time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+static ktime_t ktime_get(void)
+{
+ struct timespec now;
+
+ ktime_get_ts(&now);
+
+ return timespec_to_ktime(now);
+}
+
+/**
+ * ktime_get_real - get the real (wall-) time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+static ktime_t ktime_get_real(void)
+{
+ struct timespec now;
+
+ getnstimeofday(&now);
+
+ return timespec_to_ktime(now);
+}
+
+EXPORT_SYMBOL_GPL(ktime_get_real);
+
+/*
+ * 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
+
+static DEFINE_PER_CPU(struct hrtimer_base, hrtimer_bases[MAX_HRTIMER_BASES]) =
+{
+ {
+ .index = CLOCK_REALTIME,
+ .get_time = &ktime_get_real,
+ .resolution = KTIME_REALTIME_RES,
+ },
+ {
+ .index = CLOCK_MONOTONIC,
+ .get_time = &ktime_get,
+ .resolution = KTIME_MONOTONIC_RES,
+ },
+};
+
+/**
+ * ktime_get_ts - get the monotonic clock in timespec format
+ *
+ * @ts: pointer to timespec variable
+ *
+ * The function calculates the monotonic clock from the realtime
+ * clock and the wall_to_monotonic offset and stores the result
+ * in normalized timespec format in the variable pointed to by ts.
+ */
+void ktime_get_ts(struct timespec *ts)
+{
+ struct timespec tomono;
+ unsigned long seq;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+ getnstimeofday(ts);
+ tomono = wall_to_monotonic;
+
+ } while (read_seqretry(&xtime_lock, seq));
+
+ set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
+ ts->tv_nsec + tomono.tv_nsec);
+}
+EXPORT_SYMBOL_GPL(ktime_get_ts);
+
+/*
+ * Get the coarse grained time at the softirq based on xtime and
+ * wall_to_monotonic.
+ */
+static void hrtimer_get_softirq_time(struct hrtimer_base *base)
+{
+ ktime_t xtim, tomono;
+ unsigned long seq;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+ xtim = timespec_to_ktime(xtime);
+ tomono = timespec_to_ktime(wall_to_monotonic);
+
+ } while (read_seqretry(&xtime_lock, seq));
+
+ base[CLOCK_REALTIME].softirq_time = xtim;
+ base[CLOCK_MONOTONIC].softirq_time = ktime_add(xtim, tomono);
+}
+
+/*
+ * Functions and macros which are different for UP/SMP systems are kept in a
+ * single place
+ */
+#ifdef CONFIG_SMP
+
+#define set_curr_timer(b, t) do { (b)->curr_timer = (t); } while (0)
+
+/*
+ * We are using hashed locking: holding per_cpu(hrtimer_bases)[n].lock
+ * means that all timers which are tied to this base via timer->base are
+ * locked, and the base itself is locked too.
+ *
+ * So __run_timers/migrate_timers can safely modify all timers which could
+ * be found on the lists/queues.
+ *
+ * When the timer's base is locked, and the timer removed from list, it is
+ * possible to set timer->base = NULL and drop the lock: the timer remains
+ * locked.
+ */
+static struct hrtimer_base *lock_hrtimer_base(const struct hrtimer *timer,
+ unsigned long *flags)
+{
+ struct hrtimer_base *base;
+
+ for (;;) {
+ base = timer->base;
+ if (likely(base != NULL)) {
+ spin_lock_irqsave(&base->lock, *flags);
+ if (likely(base == timer->base))
+ return base;
+ /* The timer has migrated to another CPU: */
+ spin_unlock_irqrestore(&base->lock, *flags);
+ }
+ cpu_relax();
+ }
+}
+
+/*
+ * Switch the timer base to the current CPU when possible.
+ */
+static inline struct hrtimer_base *
+switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_base *base)
+{
+ struct hrtimer_base *new_base;
+
+ new_base = &__get_cpu_var(hrtimer_bases[base->index]);
+
+ if (base != new_base) {
+ /*
+ * We are trying to schedule the timer on the local CPU.
+ * However we can't change timer's base while it is running,
+ * so we keep it on the same CPU. No hassle vs. reprogramming
+ * the event source in the high resolution case. The softirq
+ * code will take care of this when the timer function has
+ * completed. There is no conflict as we hold the lock until
+ * the timer is enqueued.
+ */
+ if (unlikely(base->curr_timer == timer))
+ return base;
+
+ /* See the comment in lock_timer_base() */
+ timer->base = NULL;
+ spin_unlock(&base->lock);
+ spin_lock(&new_base->lock);
+ timer->base = new_base;
+ }
+ return new_base;
+}
+
+#else /* CONFIG_SMP */
+
+#define set_curr_timer(b, t) do { } while (0)
+
+static inline struct hrtimer_base *
+lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
+{
+ struct hrtimer_base *base = timer->base;
+
+ spin_lock_irqsave(&base->lock, *flags);
+
+ return base;
+}
+
+#define switch_hrtimer_base(t, b) (b)
+
+#endif /* !CONFIG_SMP */
+
+/*
+ * Functions for the union type storage format of ktime_t which are
+ * too large for inlining:
+ */
+#if BITS_PER_LONG < 64
+# ifndef CONFIG_KTIME_SCALAR
+/**
+ * ktime_add_ns - Add a scalar nanoseconds value to a ktime_t variable
+ *
+ * @kt: addend
+ * @nsec: the scalar nsec value to add
+ *
+ * Returns the sum of kt and nsec in ktime_t format
+ */
+ktime_t ktime_add_ns(const ktime_t kt, u64 nsec)
+{
+ ktime_t tmp;
+
+ if (likely(nsec < NSEC_PER_SEC)) {
+ tmp.tv64 = nsec;
+ } else {
+ unsigned long rem = do_div(nsec, NSEC_PER_SEC);
+
+ tmp = ktime_set((long)nsec, rem);
+ }
+
+ return ktime_add(kt, tmp);
+}
+
+#else /* CONFIG_KTIME_SCALAR */
+
+# endif /* !CONFIG_KTIME_SCALAR */
+
+/*
+ * Divide a ktime value by a nanosecond value
+ */
+static unsigned long ktime_divns(const ktime_t kt, s64 div)
+{
+ u64 dclc, inc, dns;
+ int sft = 0;
+
+ dclc = dns = ktime_to_ns(kt);
+ inc = div;
+ /* Make sure the divisor is less than 2^32: */
+ while (div >> 32) {
+ sft++;
+ div >>= 1;
+ }
+ dclc >>= sft;
+ do_div(dclc, (unsigned long) div);
+
+ return (unsigned long) dclc;
+}
+
+#else /* BITS_PER_LONG < 64 */
+# define ktime_divns(kt, div) (unsigned long)((kt).tv64 / (div))
+#endif /* BITS_PER_LONG >= 64 */
+
+/*
+ * Counterpart to lock_timer_base above:
+ */
+static inline
+void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
+{
+ spin_unlock_irqrestore(&timer->base->lock, *flags);
+}
+
+/**
+ * hrtimer_forward - forward the timer expiry
+ *
+ * @timer: hrtimer to forward
+ * @now: forward past this time
+ * @interval: the interval to forward
+ *
+ * Forward the timer expiry so it will expire in the future.
+ * Returns the number of overruns.
+ */
+unsigned long
+hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
+{
+ unsigned long orun = 1;
+ ktime_t delta;
+
+ delta = ktime_sub(now, timer->expires);
+
+ 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)) {
+ s64 incr = ktime_to_ns(interval);
+
+ orun = ktime_divns(delta, incr);
+ timer->expires = ktime_add_ns(timer->expires, incr * orun);
+ if (timer->expires.tv64 > now.tv64)
+ return orun;
+ /*
+ * This (and the ktime_add() below) is the
+ * correction for exact:
+ */
+ orun++;
+ }
+ timer->expires = ktime_add(timer->expires, interval);
+
+ return orun;
+}
+
+/*
+ * enqueue_hrtimer - internal function to (re)start a timer
+ *
+ * The timer is inserted in expiry order. Insertion into the
+ * red black tree is O(log(n)). Must hold the base lock.
+ */
+static void enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
+{
+ struct rb_node **link = &base->active.rb_node;
+ struct rb_node *parent = NULL;
+ struct hrtimer *entry;
+
+ /*
+ * Find the right place in the rbtree:
+ */
+ while (*link) {
+ parent = *link;
+ entry = rb_entry(parent, struct hrtimer, node);
+ /*
+ * We dont care about collisions. Nodes with
+ * the same expiry time stay together.
+ */
+ if (timer->expires.tv64 < entry->expires.tv64)
+ link = &(*link)->rb_left;
+ else
+ link = &(*link)->rb_right;
+ }
+
+ /*
+ * 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);
+
+ 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
+ *
+ * Caller must hold the base lock.
+ */
+static void __remove_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
+{
+ /*
+ * Remove the timer from the rbtree and replace the
+ * first entry pointer if necessary.
+ */
+ if (base->first == &timer->node)
+ base->first = rb_next(&timer->node);
+ rb_erase(&timer->node, &base->active);
+ timer->node.rb_parent = HRTIMER_INACTIVE;
+}
+
+/*
+ * remove hrtimer, called with base lock held
+ */
+static inline int
+remove_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
+{
+ if (hrtimer_active(timer)) {
+ __remove_hrtimer(timer, base);
+ return 1;
+ }
+ return 0;
+}
+
+/**
+ * hrtimer_start - (re)start an relative timer on the current CPU
+ *
+ * @timer: the timer to be added
+ * @tim: expiry time
+ * @mode: expiry mode: absolute (HRTIMER_ABS) or relative (HRTIMER_REL)
+ *
+ * Returns:
+ * 0 on success
+ * 1 when the timer was active
+ */
+int
+hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
+{
+ struct hrtimer_base *base, *new_base;
+ unsigned long flags;
+ int ret;
+
+ base = lock_hrtimer_base(timer, &flags);
+
+ /* Remove an active timer from the queue: */
+ ret = remove_hrtimer(timer, base);
+
+ /* Switch the timer base, if necessary: */
+ new_base = switch_hrtimer_base(timer, base);
+
+ 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);
+
+ unlock_hrtimer_base(timer, &flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(hrtimer_start);
+
+/**
+ * hrtimer_try_to_cancel - try to deactivate a timer
+ *
+ * @timer: hrtimer to stop
+ *
+ * Returns:
+ * 0 when the timer was not active
+ * 1 when the timer was active
+ * -1 when the timer is currently excuting the callback function and
+ * can not be stopped
+ */
+int hrtimer_try_to_cancel(struct hrtimer *timer)
+{
+ struct hrtimer_base *base;
+ unsigned long flags;
+ int ret = -1;
+
+ base = lock_hrtimer_base(timer, &flags);
+
+ if (base->curr_timer != timer)
+ ret = remove_hrtimer(timer, base);
+
+ unlock_hrtimer_base(timer, &flags);
+
+ return ret;
+
+}
+EXPORT_SYMBOL_GPL(hrtimer_try_to_cancel);
+
+/**
+ * hrtimer_cancel - cancel a timer and wait for the handler to finish.
+ *
+ * @timer: the timer to be cancelled
+ *
+ * Returns:
+ * 0 when the timer was not active
+ * 1 when the timer was active
+ */
+int hrtimer_cancel(struct hrtimer *timer)
+{
+ for (;;) {
+ int ret = hrtimer_try_to_cancel(timer);
+
+ if (ret >= 0)
+ return ret;
+ cpu_relax();
+ }
+}
+EXPORT_SYMBOL_GPL(hrtimer_cancel);
+
+/**
+ * hrtimer_get_remaining - get remaining time for the timer
+ *
+ * @timer: the timer to read
+ */
+ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
+{
+ struct hrtimer_base *base;
+ unsigned long flags;
+ ktime_t rem;
+
+ base = lock_hrtimer_base(timer, &flags);
+ rem = ktime_sub(timer->expires, timer->base->get_time());
+ unlock_hrtimer_base(timer, &flags);
+
+ return rem;
+}
+EXPORT_SYMBOL_GPL(hrtimer_get_remaining);
+
+#ifdef CONFIG_NO_IDLE_HZ
+/**
+ * hrtimer_get_next_event - get the time until next expiry event
+ *
+ * Returns the delta to the next expiry event or KTIME_MAX if no timer
+ * is pending.
+ */
+ktime_t hrtimer_get_next_event(void)
+{
+ struct hrtimer_base *base = __get_cpu_var(hrtimer_bases);
+ ktime_t delta, mindelta = { .tv64 = KTIME_MAX };
+ unsigned long flags;
+ int i;
+
+ for (i = 0; i < MAX_HRTIMER_BASES; i++, base++) {
+ struct hrtimer *timer;
+
+ spin_lock_irqsave(&base->lock, flags);
+ if (!base->first) {
+ spin_unlock_irqrestore(&base->lock, flags);
+ continue;
+ }
+ timer = rb_entry(base->first, struct hrtimer, node);
+ delta.tv64 = timer->expires.tv64;
+ spin_unlock_irqrestore(&base->lock, flags);
+ delta = ktime_sub(delta, base->get_time());
+ if (delta.tv64 < mindelta.tv64)
+ mindelta.tv64 = delta.tv64;
+ }
+ if (mindelta.tv64 < 0)
+ mindelta.tv64 = 0;
+ return mindelta;
+}
+#endif
+
+/**
+ * hrtimer_init - initialize a timer to the given clock
+ *
+ * @timer: the timer to be initialized
+ * @clock_id: the clock to be used
+ * @mode: timer mode abs/rel
+ */
+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());
+
+ if (clock_id == CLOCK_REALTIME && mode != HRTIMER_ABS)
+ clock_id = CLOCK_MONOTONIC;
+
+ timer->base = &bases[clock_id];
+ timer->node.rb_parent = HRTIMER_INACTIVE;
+}
+EXPORT_SYMBOL_GPL(hrtimer_init);
+
+/**
+ * hrtimer_get_res - get the timer resolution for a clock
+ *
+ * @which_clock: which clock to query
+ * @tp: pointer to timespec variable to store the resolution
+ *
+ * Store the resolution of the clock selected by which_clock in the
+ * variable pointed to by tp.
+ */
+int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp)
+{
+ struct hrtimer_base *bases;
+
+ bases = per_cpu(hrtimer_bases, raw_smp_processor_id());
+ *tp = ktime_to_timespec(bases[which_clock].resolution);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hrtimer_get_res);
+
+/*
+ * Expire the per base hrtimer-queue:
+ */
+static inline void run_hrtimer_queue(struct hrtimer_base *base)
+{
+ struct rb_node *node;
+
+ if (!base->first)
+ return;
+
+ if (base->get_softirq_time)
+ base->softirq_time = base->get_softirq_time();
+
+ spin_lock_irq(&base->lock);
+
+ while ((node = base->first)) {
+ struct hrtimer *timer;
+ int (*fn)(struct hrtimer *);
+ int restart;
+
+ timer = rb_entry(node, struct hrtimer, node);
+ if (base->softirq_time.tv64 <= timer->expires.tv64)
+ break;
+
+ fn = timer->function;
+ set_curr_timer(base, timer);
+ __remove_hrtimer(timer, base);
+ spin_unlock_irq(&base->lock);
+
+ restart = fn(timer);
+
+ spin_lock_irq(&base->lock);
+
+ if (restart != HRTIMER_NORESTART) {
+ BUG_ON(hrtimer_active(timer));
+ enqueue_hrtimer(timer, base);
+ }
+ }
+ set_curr_timer(base, NULL);
+ spin_unlock_irq(&base->lock);
+}
+
+/*
+ * Called from timer softirq every jiffy, expire hrtimers:
+ */
+void hrtimer_run_queues(void)
+{
+ struct hrtimer_base *base = __get_cpu_var(hrtimer_bases);
+ int i;
+
+ hrtimer_get_softirq_time(base);
+
+ for (i = 0; i < MAX_HRTIMER_BASES; i++)
+ run_hrtimer_queue(&base[i]);
+}
+
+/*
+ * Sleep related functions:
+ */
+static int hrtimer_wakeup(struct hrtimer *timer)
+{
+ struct hrtimer_sleeper *t =
+ container_of(timer, struct hrtimer_sleeper, timer);
+ struct task_struct *task = t->task;
+
+ t->task = NULL;
+ if (task)
+ wake_up_process(task);
+
+ return HRTIMER_NORESTART;
+}
+
+void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, task_t *task)
+{
+ sl->timer.function = hrtimer_wakeup;
+ sl->task = task;
+}
+
+static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
+{
+ hrtimer_init_sleeper(t, current);
+
+ do {
+ set_current_state(TASK_INTERRUPTIBLE);
+ hrtimer_start(&t->timer, t->timer.expires, mode);
+
+ schedule();
+
+ hrtimer_cancel(&t->timer);
+ mode = HRTIMER_ABS;
+
+ } while (t->task && !signal_pending(current));
+
+ return t->task == NULL;
+}
+
+static long __sched nanosleep_restart(struct restart_block *restart)
+{
+ struct hrtimer_sleeper t;
+ struct timespec __user *rmtp;
+ struct timespec tu;
+ ktime_t time;
+
+ restart->fn = do_no_restart_syscall;
+
+ hrtimer_init(&t.timer, restart->arg3, HRTIMER_ABS);
+ t.timer.expires.tv64 = ((u64)restart->arg1 << 32) | (u64) restart->arg0;
+
+ if (do_nanosleep(&t, HRTIMER_ABS))
+ return 0;
+
+ rmtp = (struct timespec __user *) restart->arg2;
+ if (rmtp) {
+ time = ktime_sub(t.timer.expires, t.timer.base->get_time());
+ if (time.tv64 <= 0)
+ return 0;
+ tu = ktime_to_timespec(time);
+ if (copy_to_user(rmtp, &tu, sizeof(tu)))
+ return -EFAULT;
+ }
+
+ restart->fn = nanosleep_restart;
+
+ /* The other values in restart are already filled in */
+ return -ERESTART_RESTARTBLOCK;
+}
+
+long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+ const enum hrtimer_mode mode, const clockid_t clockid)
+{
+ struct restart_block *restart;
+ struct hrtimer_sleeper t;
+ struct timespec tu;
+ ktime_t rem;
+
+ hrtimer_init(&t.timer, clockid, mode);
+ t.timer.expires = timespec_to_ktime(*rqtp);
+ if (do_nanosleep(&t, mode))
+ return 0;
+
+ /* Absolute timers do not update the rmtp value and restart: */
+ if (mode == HRTIMER_ABS)
+ return -ERESTARTNOHAND;
+
+ if (rmtp) {
+ rem = ktime_sub(t.timer.expires, t.timer.base->get_time());
+ if (rem.tv64 <= 0)
+ return 0;
+ tu = ktime_to_timespec(rem);
+ if (copy_to_user(rmtp, &tu, sizeof(tu)))
+ return -EFAULT;
+ }
+
+ restart = ¤t_thread_info()->restart_block;
+ restart->fn = nanosleep_restart;
+ restart->arg0 = t.timer.expires.tv64 & 0xFFFFFFFF;
+ restart->arg1 = t.timer.expires.tv64 >> 32;
+ restart->arg2 = (unsigned long) rmtp;
+ restart->arg3 = (unsigned long) t.timer.base->index;
+
+ return -ERESTART_RESTARTBLOCK;
+}
+
+asmlinkage long
+sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
+{
+ struct timespec tu;
+
+ if (copy_from_user(&tu, rqtp, sizeof(tu)))
+ return -EFAULT;
+
+ if (!timespec_valid(&tu))
+ return -EINVAL;
+
+ return hrtimer_nanosleep(&tu, rmtp, HRTIMER_REL, CLOCK_MONOTONIC);
+}
+
+/*
+ * Functions related to boot-time initialization:
+ */
+static void __devinit init_hrtimers_cpu(int cpu)
+{
+ struct hrtimer_base *base = per_cpu(hrtimer_bases, cpu);
+ int i;
+
+ for (i = 0; i < MAX_HRTIMER_BASES; i++, base++)
+ spin_lock_init(&base->lock);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static void migrate_hrtimer_list(struct hrtimer_base *old_base,
+ struct hrtimer_base *new_base)
+{
+ struct hrtimer *timer;
+ struct rb_node *node;
+
+ while ((node = rb_first(&old_base->active))) {
+ timer = rb_entry(node, struct hrtimer, node);
+ __remove_hrtimer(timer, old_base);
+ timer->base = new_base;
+ enqueue_hrtimer(timer, new_base);
+ }
+}
+
+static void migrate_hrtimers(int cpu)
+{
+ struct hrtimer_base *old_base, *new_base;
+ int i;
+
+ BUG_ON(cpu_online(cpu));
+ old_base = per_cpu(hrtimer_bases, cpu);
+ new_base = get_cpu_var(hrtimer_bases);
+
+ local_irq_disable();
+
+ for (i = 0; i < MAX_HRTIMER_BASES; i++) {
+
+ spin_lock(&new_base->lock);
+ spin_lock(&old_base->lock);
+
+ BUG_ON(old_base->curr_timer);
+
+ migrate_hrtimer_list(old_base, new_base);
+
+ spin_unlock(&old_base->lock);
+ spin_unlock(&new_base->lock);
+ old_base++;
+ new_base++;
+ }
+
+ local_irq_enable();
+ put_cpu_var(hrtimer_bases);
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+static int hrtimer_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ long cpu = (long)hcpu;
+
+ switch (action) {
+
+ case CPU_UP_PREPARE:
+ init_hrtimers_cpu(cpu);
+ break;
+
+#ifdef CONFIG_HOTPLUG_CPU
+ case CPU_DEAD:
+ migrate_hrtimers(cpu);
+ break;
+#endif
+
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block hrtimers_nb = {
+ .notifier_call = hrtimer_cpu_notify,
+};
+
+void __init hrtimers_init(void)
+{
+ hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE,
+ (void *)(long)smp_processor_id());
+ register_cpu_notifier(&hrtimers_nb);
+}
+
git://git.onelab.eu / linux-2.6.git / blobdiff