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authorThomas Gleixner <tglx@linutronix.de>2014-06-22 12:06:40 +0200
committerThomas Gleixner <tglx@linutronix.de>2014-06-23 11:22:35 +0200
commit5cee964597260237dd2cabb3ec22bba0da24b25d (patch)
treef548efb4181a4cffb026adf43178e65330533e87 /kernel/hrtimer.c
parent58394271c610e9c65dd0165a1c1f6dec75dc5f3e (diff)
downloadlinux-5cee964597260237dd2cabb3ec22bba0da24b25d.tar.bz2
time/timers: Move all time(r) related files into kernel/time
Except for Kconfig.HZ. That needs a separate treatment. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/hrtimer.c')
-rw-r--r--kernel/hrtimer.c1915
1 files changed, 0 insertions, 1915 deletions
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
deleted file mode 100644
index 3ab28993f6e0..000000000000
--- a/kernel/hrtimer.c
+++ /dev/null
@@ -1,1915 +0,0 @@
-/*
- * linux/kernel/hrtimer.c
- *
- * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
- * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
- * Copyright(C) 2006-2007 Timesys Corp., Thomas Gleixner
- *
- * 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/export.h>
-#include <linux/percpu.h>
-#include <linux/hrtimer.h>
-#include <linux/notifier.h>
-#include <linux/syscalls.h>
-#include <linux/kallsyms.h>
-#include <linux/interrupt.h>
-#include <linux/tick.h>
-#include <linux/seq_file.h>
-#include <linux/err.h>
-#include <linux/debugobjects.h>
-#include <linux/sched.h>
-#include <linux/sched/sysctl.h>
-#include <linux/sched/rt.h>
-#include <linux/sched/deadline.h>
-#include <linux/timer.h>
-#include <linux/freezer.h>
-
-#include <asm/uaccess.h>
-
-#include <trace/events/timer.h>
-
-/*
- * The timer bases:
- *
- * There are more clockids then hrtimer bases. Thus, we index
- * into the timer bases by the hrtimer_base_type enum. When trying
- * to reach a base using a clockid, hrtimer_clockid_to_base()
- * is used to convert from clockid to the proper hrtimer_base_type.
- */
-DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
-{
-
- .lock = __RAW_SPIN_LOCK_UNLOCKED(hrtimer_bases.lock),
- .clock_base =
- {
- {
- .index = HRTIMER_BASE_MONOTONIC,
- .clockid = CLOCK_MONOTONIC,
- .get_time = &ktime_get,
- .resolution = KTIME_LOW_RES,
- },
- {
- .index = HRTIMER_BASE_REALTIME,
- .clockid = CLOCK_REALTIME,
- .get_time = &ktime_get_real,
- .resolution = KTIME_LOW_RES,
- },
- {
- .index = HRTIMER_BASE_BOOTTIME,
- .clockid = CLOCK_BOOTTIME,
- .get_time = &ktime_get_boottime,
- .resolution = KTIME_LOW_RES,
- },
- {
- .index = HRTIMER_BASE_TAI,
- .clockid = CLOCK_TAI,
- .get_time = &ktime_get_clocktai,
- .resolution = KTIME_LOW_RES,
- },
- }
-};
-
-static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
- [CLOCK_REALTIME] = HRTIMER_BASE_REALTIME,
- [CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC,
- [CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME,
- [CLOCK_TAI] = HRTIMER_BASE_TAI,
-};
-
-static inline int hrtimer_clockid_to_base(clockid_t clock_id)
-{
- return hrtimer_clock_to_base_table[clock_id];
-}
-
-
-/*
- * Get the coarse grained time at the softirq based on xtime and
- * wall_to_monotonic.
- */
-static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
-{
- ktime_t xtim, mono, boot;
- struct timespec xts, tom, slp;
- s32 tai_offset;
-
- get_xtime_and_monotonic_and_sleep_offset(&xts, &tom, &slp);
- tai_offset = timekeeping_get_tai_offset();
-
- xtim = timespec_to_ktime(xts);
- mono = ktime_add(xtim, timespec_to_ktime(tom));
- boot = ktime_add(mono, timespec_to_ktime(slp));
- base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim;
- base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = mono;
- base->clock_base[HRTIMER_BASE_BOOTTIME].softirq_time = boot;
- base->clock_base[HRTIMER_BASE_TAI].softirq_time =
- ktime_add(xtim, ktime_set(tai_offset, 0));
-}
-
-/*
- * Functions and macros which are different for UP/SMP systems are kept in a
- * single place
- */
-#ifdef CONFIG_SMP
-
-/*
- * 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_clock_base *lock_hrtimer_base(const struct hrtimer *timer,
- unsigned long *flags)
-{
- struct hrtimer_clock_base *base;
-
- for (;;) {
- base = timer->base;
- if (likely(base != NULL)) {
- raw_spin_lock_irqsave(&base->cpu_base->lock, *flags);
- if (likely(base == timer->base))
- return base;
- /* The timer has migrated to another CPU: */
- raw_spin_unlock_irqrestore(&base->cpu_base->lock, *flags);
- }
- cpu_relax();
- }
-}
-
-/*
- * With HIGHRES=y we do not migrate the timer when it is expiring
- * before the next event on the target cpu because we cannot reprogram
- * the target cpu hardware and we would cause it to fire late.
- *
- * Called with cpu_base->lock of target cpu held.
- */
-static int
-hrtimer_check_target(struct hrtimer *timer, struct hrtimer_clock_base *new_base)
-{
-#ifdef CONFIG_HIGH_RES_TIMERS
- ktime_t expires;
-
- if (!new_base->cpu_base->hres_active)
- return 0;
-
- expires = ktime_sub(hrtimer_get_expires(timer), new_base->offset);
- return expires.tv64 <= new_base->cpu_base->expires_next.tv64;
-#else
- return 0;
-#endif
-}
-
-/*
- * Switch the timer base to the current CPU when possible.
- */
-static inline struct hrtimer_clock_base *
-switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base,
- int pinned)
-{
- struct hrtimer_clock_base *new_base;
- struct hrtimer_cpu_base *new_cpu_base;
- int this_cpu = smp_processor_id();
- int cpu = get_nohz_timer_target(pinned);
- int basenum = base->index;
-
-again:
- new_cpu_base = &per_cpu(hrtimer_bases, cpu);
- new_base = &new_cpu_base->clock_base[basenum];
-
- if (base != new_base) {
- /*
- * We are trying to move timer to new_base.
- * 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(hrtimer_callback_running(timer)))
- return base;
-
- /* See the comment in lock_timer_base() */
- timer->base = NULL;
- raw_spin_unlock(&base->cpu_base->lock);
- raw_spin_lock(&new_base->cpu_base->lock);
-
- if (cpu != this_cpu && hrtimer_check_target(timer, new_base)) {
- cpu = this_cpu;
- raw_spin_unlock(&new_base->cpu_base->lock);
- raw_spin_lock(&base->cpu_base->lock);
- timer->base = base;
- goto again;
- }
- timer->base = new_base;
- } else {
- if (cpu != this_cpu && hrtimer_check_target(timer, new_base)) {
- cpu = this_cpu;
- goto again;
- }
- }
- return new_base;
-}
-
-#else /* CONFIG_SMP */
-
-static inline struct hrtimer_clock_base *
-lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
-{
- struct hrtimer_clock_base *base = timer->base;
-
- raw_spin_lock_irqsave(&base->cpu_base->lock, *flags);
-
- return base;
-}
-
-# define switch_hrtimer_base(t, b, p) (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);
-
- /* Make sure nsec fits into long */
- if (unlikely(nsec > KTIME_SEC_MAX))
- return (ktime_t){ .tv64 = KTIME_MAX };
-
- tmp = ktime_set((long)nsec, rem);
- }
-
- return ktime_add(kt, tmp);
-}
-
-EXPORT_SYMBOL_GPL(ktime_add_ns);
-
-/**
- * ktime_sub_ns - Subtract a scalar nanoseconds value from a ktime_t variable
- * @kt: minuend
- * @nsec: the scalar nsec value to subtract
- *
- * Returns the subtraction of @nsec from @kt in ktime_t format
- */
-ktime_t ktime_sub_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_sub(kt, tmp);
-}
-
-EXPORT_SYMBOL_GPL(ktime_sub_ns);
-# endif /* !CONFIG_KTIME_SCALAR */
-
-/*
- * Divide a ktime value by a nanosecond value
- */
-u64 ktime_divns(const ktime_t kt, s64 div)
-{
- u64 dclc;
- int sft = 0;
-
- dclc = ktime_to_ns(kt);
- /* Make sure the divisor is less than 2^32: */
- while (div >> 32) {
- sft++;
- div >>= 1;
- }
- dclc >>= sft;
- do_div(dclc, (unsigned long) div);
-
- return dclc;
-}
-#endif /* BITS_PER_LONG >= 64 */
-
-/*
- * Add two ktime values and do a safety check for overflow:
- */
-ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs)
-{
- ktime_t res = ktime_add(lhs, rhs);
-
- /*
- * We use KTIME_SEC_MAX here, the maximum timeout which we can
- * return to user space in a timespec:
- */
- if (res.tv64 < 0 || res.tv64 < lhs.tv64 || res.tv64 < rhs.tv64)
- res = ktime_set(KTIME_SEC_MAX, 0);
-
- return res;
-}
-
-EXPORT_SYMBOL_GPL(ktime_add_safe);
-
-#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
-
-static struct debug_obj_descr hrtimer_debug_descr;
-
-static void *hrtimer_debug_hint(void *addr)
-{
- return ((struct hrtimer *) addr)->function;
-}
-
-/*
- * fixup_init is called when:
- * - an active object is initialized
- */
-static int hrtimer_fixup_init(void *addr, enum debug_obj_state state)
-{
- struct hrtimer *timer = addr;
-
- switch (state) {
- case ODEBUG_STATE_ACTIVE:
- hrtimer_cancel(timer);
- debug_object_init(timer, &hrtimer_debug_descr);
- return 1;
- default:
- return 0;
- }
-}
-
-/*
- * fixup_activate is called when:
- * - an active object is activated
- * - an unknown object is activated (might be a statically initialized object)
- */
-static int hrtimer_fixup_activate(void *addr, enum debug_obj_state state)
-{
- switch (state) {
-
- case ODEBUG_STATE_NOTAVAILABLE:
- WARN_ON_ONCE(1);
- return 0;
-
- case ODEBUG_STATE_ACTIVE:
- WARN_ON(1);
-
- default:
- return 0;
- }
-}
-
-/*
- * fixup_free is called when:
- * - an active object is freed
- */
-static int hrtimer_fixup_free(void *addr, enum debug_obj_state state)
-{
- struct hrtimer *timer = addr;
-
- switch (state) {
- case ODEBUG_STATE_ACTIVE:
- hrtimer_cancel(timer);
- debug_object_free(timer, &hrtimer_debug_descr);
- return 1;
- default:
- return 0;
- }
-}
-
-static struct debug_obj_descr hrtimer_debug_descr = {
- .name = "hrtimer",
- .debug_hint = hrtimer_debug_hint,
- .fixup_init = hrtimer_fixup_init,
- .fixup_activate = hrtimer_fixup_activate,
- .fixup_free = hrtimer_fixup_free,
-};
-
-static inline void debug_hrtimer_init(struct hrtimer *timer)
-{
- debug_object_init(timer, &hrtimer_debug_descr);
-}
-
-static inline void debug_hrtimer_activate(struct hrtimer *timer)
-{
- debug_object_activate(timer, &hrtimer_debug_descr);
-}
-
-static inline void debug_hrtimer_deactivate(struct hrtimer *timer)
-{
- debug_object_deactivate(timer, &hrtimer_debug_descr);
-}
-
-static inline void debug_hrtimer_free(struct hrtimer *timer)
-{
- debug_object_free(timer, &hrtimer_debug_descr);
-}
-
-static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
- enum hrtimer_mode mode);
-
-void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
- enum hrtimer_mode mode)
-{
- debug_object_init_on_stack(timer, &hrtimer_debug_descr);
- __hrtimer_init(timer, clock_id, mode);
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
-
-void destroy_hrtimer_on_stack(struct hrtimer *timer)
-{
- debug_object_free(timer, &hrtimer_debug_descr);
-}
-
-#else
-static inline void debug_hrtimer_init(struct hrtimer *timer) { }
-static inline void debug_hrtimer_activate(struct hrtimer *timer) { }
-static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }
-#endif
-
-static inline void
-debug_init(struct hrtimer *timer, clockid_t clockid,
- enum hrtimer_mode mode)
-{
- debug_hrtimer_init(timer);
- trace_hrtimer_init(timer, clockid, mode);
-}
-
-static inline void debug_activate(struct hrtimer *timer)
-{
- debug_hrtimer_activate(timer);
- trace_hrtimer_start(timer);
-}
-
-static inline void debug_deactivate(struct hrtimer *timer)
-{
- debug_hrtimer_deactivate(timer);
- trace_hrtimer_cancel(timer);
-}
-
-/* High resolution timer related functions */
-#ifdef CONFIG_HIGH_RES_TIMERS
-
-/*
- * High resolution timer enabled ?
- */
-static int hrtimer_hres_enabled __read_mostly = 1;
-
-/*
- * Enable / Disable high resolution mode
- */
-static int __init setup_hrtimer_hres(char *str)
-{
- if (!strcmp(str, "off"))
- hrtimer_hres_enabled = 0;
- else if (!strcmp(str, "on"))
- hrtimer_hres_enabled = 1;
- else
- return 0;
- return 1;
-}
-
-__setup("highres=", setup_hrtimer_hres);
-
-/*
- * hrtimer_high_res_enabled - query, if the highres mode is enabled
- */
-static inline int hrtimer_is_hres_enabled(void)
-{
- return hrtimer_hres_enabled;
-}
-
-/*
- * Is the high resolution mode active ?
- */
-static inline int hrtimer_hres_active(void)
-{
- return __this_cpu_read(hrtimer_bases.hres_active);
-}
-
-/*
- * Reprogram the event source with checking both queues for the
- * next event
- * Called with interrupts disabled and base->lock held
- */
-static void
-hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
-{
- int i;
- struct hrtimer_clock_base *base = cpu_base->clock_base;
- ktime_t expires, expires_next;
-
- expires_next.tv64 = KTIME_MAX;
-
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
- struct hrtimer *timer;
- struct timerqueue_node *next;
-
- next = timerqueue_getnext(&base->active);
- if (!next)
- continue;
- timer = container_of(next, struct hrtimer, node);
-
- expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
- /*
- * clock_was_set() has changed base->offset so the
- * result might be negative. Fix it up to prevent a
- * false positive in clockevents_program_event()
- */
- if (expires.tv64 < 0)
- expires.tv64 = 0;
- if (expires.tv64 < expires_next.tv64)
- expires_next = expires;
- }
-
- if (skip_equal && expires_next.tv64 == cpu_base->expires_next.tv64)
- return;
-
- cpu_base->expires_next.tv64 = expires_next.tv64;
-
- /*
- * If a hang was detected in the last timer interrupt then we
- * leave the hang delay active in the hardware. We want the
- * system to make progress. That also prevents the following
- * scenario:
- * T1 expires 50ms from now
- * T2 expires 5s from now
- *
- * T1 is removed, so this code is called and would reprogram
- * the hardware to 5s from now. Any hrtimer_start after that
- * will not reprogram the hardware due to hang_detected being
- * set. So we'd effectivly block all timers until the T2 event
- * fires.
- */
- if (cpu_base->hang_detected)
- return;
-
- if (cpu_base->expires_next.tv64 != KTIME_MAX)
- tick_program_event(cpu_base->expires_next, 1);
-}
-
-/*
- * Shared reprogramming for clock_realtime and clock_monotonic
- *
- * When a timer is enqueued and expires earlier than the already enqueued
- * timers, we have to check, whether it expires earlier than the timer for
- * which the clock event device was armed.
- *
- * Called with interrupts disabled and base->cpu_base.lock held
- */
-static int hrtimer_reprogram(struct hrtimer *timer,
- struct hrtimer_clock_base *base)
-{
- struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
- ktime_t expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
- int res;
-
- WARN_ON_ONCE(hrtimer_get_expires_tv64(timer) < 0);
-
- /*
- * When the callback is running, we do not reprogram the clock event
- * device. The timer callback is either running on a different CPU or
- * the callback is executed in the hrtimer_interrupt context. The
- * reprogramming is handled either by the softirq, which called the
- * callback or at the end of the hrtimer_interrupt.
- */
- if (hrtimer_callback_running(timer))
- return 0;
-
- /*
- * CLOCK_REALTIME timer might be requested with an absolute
- * expiry time which is less than base->offset. Nothing wrong
- * about that, just avoid to call into the tick code, which
- * has now objections against negative expiry values.
- */
- if (expires.tv64 < 0)
- return -ETIME;
-
- if (expires.tv64 >= cpu_base->expires_next.tv64)
- return 0;
-
- /*
- * If a hang was detected in the last timer interrupt then we
- * do not schedule a timer which is earlier than the expiry
- * which we enforced in the hang detection. We want the system
- * to make progress.
- */
- if (cpu_base->hang_detected)
- return 0;
-
- /*
- * Clockevents returns -ETIME, when the event was in the past.
- */
- res = tick_program_event(expires, 0);
- if (!IS_ERR_VALUE(res))
- cpu_base->expires_next = expires;
- return res;
-}
-
-/*
- * Initialize the high resolution related parts of cpu_base
- */
-static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
-{
- base->expires_next.tv64 = KTIME_MAX;
- base->hres_active = 0;
-}
-
-/*
- * When High resolution timers are active, try to reprogram. Note, that in case
- * the state has HRTIMER_STATE_CALLBACK set, no reprogramming and no expiry
- * check happens. The timer gets enqueued into the rbtree. The reprogramming
- * and expiry check is done in the hrtimer_interrupt or in the softirq.
- */
-static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
- struct hrtimer_clock_base *base)
-{
- return base->cpu_base->hres_active && hrtimer_reprogram(timer, base);
-}
-
-static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
-{
- ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset;
- ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
- ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset;
-
- return ktime_get_update_offsets(offs_real, offs_boot, offs_tai);
-}
-
-/*
- * Retrigger next event is called after clock was set
- *
- * Called with interrupts disabled via on_each_cpu()
- */
-static void retrigger_next_event(void *arg)
-{
- struct hrtimer_cpu_base *base = &__get_cpu_var(hrtimer_bases);
-
- if (!hrtimer_hres_active())
- return;
-
- raw_spin_lock(&base->lock);
- hrtimer_update_base(base);
- hrtimer_force_reprogram(base, 0);
- raw_spin_unlock(&base->lock);
-}
-
-/*
- * Switch to high resolution mode
- */
-static int hrtimer_switch_to_hres(void)
-{
- int i, cpu = smp_processor_id();
- struct hrtimer_cpu_base *base = &per_cpu(hrtimer_bases, cpu);
- unsigned long flags;
-
- if (base->hres_active)
- return 1;
-
- local_irq_save(flags);
-
- if (tick_init_highres()) {
- local_irq_restore(flags);
- printk(KERN_WARNING "Could not switch to high resolution "
- "mode on CPU %d\n", cpu);
- return 0;
- }
- base->hres_active = 1;
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++)
- base->clock_base[i].resolution = KTIME_HIGH_RES;
-
- tick_setup_sched_timer();
- /* "Retrigger" the interrupt to get things going */
- retrigger_next_event(NULL);
- local_irq_restore(flags);
- return 1;
-}
-
-static void clock_was_set_work(struct work_struct *work)
-{
- clock_was_set();
-}
-
-static DECLARE_WORK(hrtimer_work, clock_was_set_work);
-
-/*
- * Called from timekeeping and resume code to reprogramm the hrtimer
- * interrupt device on all cpus.
- */
-void clock_was_set_delayed(void)
-{
- schedule_work(&hrtimer_work);
-}
-
-#else
-
-static inline int hrtimer_hres_active(void) { return 0; }
-static inline int hrtimer_is_hres_enabled(void) { return 0; }
-static inline int hrtimer_switch_to_hres(void) { return 0; }
-static inline void
-hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
-static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
- struct hrtimer_clock_base *base)
-{
- return 0;
-}
-static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { }
-static inline void retrigger_next_event(void *arg) { }
-
-#endif /* CONFIG_HIGH_RES_TIMERS */
-
-/*
- * Clock realtime was set
- *
- * Change the offset of the realtime clock vs. the monotonic
- * clock.
- *
- * We might have to reprogram the high resolution timer interrupt. On
- * SMP we call the architecture specific code to retrigger _all_ high
- * resolution timer interrupts. On UP we just disable interrupts and
- * call the high resolution interrupt code.
- */
-void clock_was_set(void)
-{
-#ifdef CONFIG_HIGH_RES_TIMERS
- /* Retrigger the CPU local events everywhere */
- on_each_cpu(retrigger_next_event, NULL, 1);
-#endif
- timerfd_clock_was_set();
-}
-
-/*
- * During resume we might have to reprogram the high resolution timer
- * interrupt on all online CPUs. However, all other CPUs will be
- * stopped with IRQs interrupts disabled so the clock_was_set() call
- * must be deferred.
- */
-void hrtimers_resume(void)
-{
- WARN_ONCE(!irqs_disabled(),
- KERN_INFO "hrtimers_resume() called with IRQs enabled!");
-
- /* Retrigger on the local CPU */
- retrigger_next_event(NULL);
- /* And schedule a retrigger for all others */
- clock_was_set_delayed();
-}
-
-static inline void timer_stats_hrtimer_set_start_info(struct hrtimer *timer)
-{
-#ifdef CONFIG_TIMER_STATS
- if (timer->start_site)
- return;
- timer->start_site = __builtin_return_address(0);
- memcpy(timer->start_comm, current->comm, TASK_COMM_LEN);
- timer->start_pid = current->pid;
-#endif
-}
-
-static inline void timer_stats_hrtimer_clear_start_info(struct hrtimer *timer)
-{
-#ifdef CONFIG_TIMER_STATS
- timer->start_site = NULL;
-#endif
-}
-
-static inline void timer_stats_account_hrtimer(struct hrtimer *timer)
-{
-#ifdef CONFIG_TIMER_STATS
- if (likely(!timer_stats_active))
- return;
- timer_stats_update_stats(timer, timer->start_pid, timer->start_site,
- timer->function, timer->start_comm, 0);
-#endif
-}
-
-/*
- * Counterpart to lock_hrtimer_base above:
- */
-static inline
-void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
-{
- raw_spin_unlock_irqrestore(&timer->base->cpu_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.
- */
-u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
-{
- u64 orun = 1;
- ktime_t delta;
-
- delta = ktime_sub(now, hrtimer_get_expires(timer));
-
- 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);
- hrtimer_add_expires_ns(timer, incr * orun);
- if (hrtimer_get_expires_tv64(timer) > now.tv64)
- return orun;
- /*
- * This (and the ktime_add() below) is the
- * correction for exact:
- */
- orun++;
- }
- hrtimer_add_expires(timer, interval);
-
- return orun;
-}
-EXPORT_SYMBOL_GPL(hrtimer_forward);
-
-/*
- * 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.
- *
- * Returns 1 when the new timer is the leftmost timer in the tree.
- */
-static int enqueue_hrtimer(struct hrtimer *timer,
- struct hrtimer_clock_base *base)
-{
- debug_activate(timer);
-
- timerqueue_add(&base->active, &timer->node);
- base->cpu_base->active_bases |= 1 << base->index;
-
- /*
- * HRTIMER_STATE_ENQUEUED is or'ed to the current state to preserve the
- * state of a possibly running callback.
- */
- timer->state |= HRTIMER_STATE_ENQUEUED;
-
- return (&timer->node == base->active.next);
-}
-
-/*
- * __remove_hrtimer - internal function to remove a timer
- *
- * Caller must hold the base lock.
- *
- * High resolution timer mode reprograms the clock event device when the
- * timer is the one which expires next. The caller can disable this by setting
- * reprogram to zero. This is useful, when the context does a reprogramming
- * anyway (e.g. timer interrupt)
- */
-static void __remove_hrtimer(struct hrtimer *timer,
- struct hrtimer_clock_base *base,
- unsigned long newstate, int reprogram)
-{
- struct timerqueue_node *next_timer;
- if (!(timer->state & HRTIMER_STATE_ENQUEUED))
- goto out;
-
- next_timer = timerqueue_getnext(&base->active);
- timerqueue_del(&base->active, &timer->node);
- if (&timer->node == next_timer) {
-#ifdef CONFIG_HIGH_RES_TIMERS
- /* Reprogram the clock event device. if enabled */
- if (reprogram && hrtimer_hres_active()) {
- ktime_t expires;
-
- expires = ktime_sub(hrtimer_get_expires(timer),
- base->offset);
- if (base->cpu_base->expires_next.tv64 == expires.tv64)
- hrtimer_force_reprogram(base->cpu_base, 1);
- }
-#endif
- }
- if (!timerqueue_getnext(&base->active))
- base->cpu_base->active_bases &= ~(1 << base->index);
-out:
- timer->state = newstate;
-}
-
-/*
- * remove hrtimer, called with base lock held
- */
-static inline int
-remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base)
-{
- if (hrtimer_is_queued(timer)) {
- unsigned long state;
- int reprogram;
-
- /*
- * Remove the timer and force reprogramming when high
- * resolution mode is active and the timer is on the current
- * CPU. If we remove a timer on another CPU, reprogramming is
- * skipped. The interrupt event on this CPU is fired and
- * reprogramming happens in the interrupt handler. This is a
- * rare case and less expensive than a smp call.
- */
- debug_deactivate(timer);
- timer_stats_hrtimer_clear_start_info(timer);
- reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases);
- /*
- * We must preserve the CALLBACK state flag here,
- * otherwise we could move the timer base in
- * switch_hrtimer_base.
- */
- state = timer->state & HRTIMER_STATE_CALLBACK;
- __remove_hrtimer(timer, base, state, reprogram);
- return 1;
- }
- return 0;
-}
-
-int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
- unsigned long delta_ns, const enum hrtimer_mode mode,
- int wakeup)
-{
- struct hrtimer_clock_base *base, *new_base;
- unsigned long flags;
- int ret, leftmost;
-
- base = lock_hrtimer_base(timer, &flags);
-
- /* Remove an active timer from the queue: */
- ret = remove_hrtimer(timer, base);
-
- if (mode & HRTIMER_MODE_REL) {
- tim = ktime_add_safe(tim, 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_safe(tim, base->resolution);
-#endif
- }
-
- hrtimer_set_expires_range_ns(timer, tim, delta_ns);
-
- /* Switch the timer base, if necessary: */
- new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);
-
- timer_stats_hrtimer_set_start_info(timer);
-
- leftmost = enqueue_hrtimer(timer, new_base);
-
- /*
- * Only allow reprogramming if the new base is on this CPU.
- * (it might still be on another CPU if the timer was pending)
- *
- * XXX send_remote_softirq() ?
- */
- if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases)
- && hrtimer_enqueue_reprogram(timer, new_base)) {
- if (wakeup) {
- /*
- * We need to drop cpu_base->lock to avoid a
- * lock ordering issue vs. rq->lock.
- */
- raw_spin_unlock(&new_base->cpu_base->lock);
- raise_softirq_irqoff(HRTIMER_SOFTIRQ);
- local_irq_restore(flags);
- return ret;
- } else {
- __raise_softirq_irqoff(HRTIMER_SOFTIRQ);
- }
- }
-
- unlock_hrtimer_base(timer, &flags);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(__hrtimer_start_range_ns);
-
-/**
- * hrtimer_start_range_ns - (re)start an hrtimer on the current CPU
- * @timer: the timer to be added
- * @tim: expiry time
- * @delta_ns: "slack" range for the timer
- * @mode: expiry mode: absolute (HRTIMER_MODE_ABS) or
- * relative (HRTIMER_MODE_REL)
- *
- * Returns:
- * 0 on success
- * 1 when the timer was active
- */
-int hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
- unsigned long delta_ns, const enum hrtimer_mode mode)
-{
- return __hrtimer_start_range_ns(timer, tim, delta_ns, mode, 1);
-}
-EXPORT_SYMBOL_GPL(hrtimer_start_range_ns);
-
-/**
- * hrtimer_start - (re)start an hrtimer on the current CPU
- * @timer: the timer to be added
- * @tim: expiry time
- * @mode: expiry mode: absolute (HRTIMER_MODE_ABS) or
- * relative (HRTIMER_MODE_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)
-{
- return __hrtimer_start_range_ns(timer, tim, 0, mode, 1);
-}
-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
- * cannot be stopped
- */
-int hrtimer_try_to_cancel(struct hrtimer *timer)
-{
- struct hrtimer_clock_base *base;
- unsigned long flags;
- int ret = -1;
-
- base = lock_hrtimer_base(timer, &flags);
-
- if (!hrtimer_callback_running(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)
-{
- unsigned long flags;
- ktime_t rem;
-
- lock_hrtimer_base(timer, &flags);
- rem = hrtimer_expires_remaining(timer);
- unlock_hrtimer_base(timer, &flags);
-
- return rem;
-}
-EXPORT_SYMBOL_GPL(hrtimer_get_remaining);
-
-#ifdef CONFIG_NO_HZ_COMMON
-/**
- * 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_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
- struct hrtimer_clock_base *base = cpu_base->clock_base;
- ktime_t delta, mindelta = { .tv64 = KTIME_MAX };
- unsigned long flags;
- int i;
-
- raw_spin_lock_irqsave(&cpu_base->lock, flags);
-
- if (!hrtimer_hres_active()) {
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
- struct hrtimer *timer;
- struct timerqueue_node *next;
-
- next = timerqueue_getnext(&base->active);
- if (!next)
- continue;
-
- timer = container_of(next, struct hrtimer, node);
- delta.tv64 = hrtimer_get_expires_tv64(timer);
- delta = ktime_sub(delta, base->get_time());
- if (delta.tv64 < mindelta.tv64)
- mindelta.tv64 = delta.tv64;
- }
- }
-
- raw_spin_unlock_irqrestore(&cpu_base->lock, flags);
-
- if (mindelta.tv64 < 0)
- mindelta.tv64 = 0;
- return mindelta;
-}
-#endif
-
-static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
- enum hrtimer_mode mode)
-{
- struct hrtimer_cpu_base *cpu_base;
- int base;
-
- memset(timer, 0, sizeof(struct hrtimer));
-
- cpu_base = &__raw_get_cpu_var(hrtimer_bases);
-
- if (clock_id == CLOCK_REALTIME && mode != HRTIMER_MODE_ABS)
- clock_id = CLOCK_MONOTONIC;
-
- base = hrtimer_clockid_to_base(clock_id);
- timer->base = &cpu_base->clock_base[base];
- timerqueue_init(&timer->node);
-
-#ifdef CONFIG_TIMER_STATS
- timer->start_site = NULL;
- timer->start_pid = -1;
- memset(timer->start_comm, 0, TASK_COMM_LEN);
-#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)
-{
- debug_init(timer, clock_id, mode);
- __hrtimer_init(timer, clock_id, mode);
-}
-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_cpu_base *cpu_base;
- int base = hrtimer_clockid_to_base(which_clock);
-
- cpu_base = &__raw_get_cpu_var(hrtimer_bases);
- *tp = ktime_to_timespec(cpu_base->clock_base[base].resolution);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(hrtimer_get_res);
-
-static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
-{
- struct hrtimer_clock_base *base = timer->base;
- struct hrtimer_cpu_base *cpu_base = base->cpu_base;
- enum hrtimer_restart (*fn)(struct hrtimer *);
- int restart;
-
- WARN_ON(!irqs_disabled());
-
- debug_deactivate(timer);
- __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0);
- timer_stats_account_hrtimer(timer);
- fn = timer->function;
-
- /*
- * Because we run timers from hardirq context, there is no chance
- * they get migrated to another cpu, therefore its safe to unlock
- * the timer base.
- */
- raw_spin_unlock(&cpu_base->lock);
- trace_hrtimer_expire_entry(timer, now);
- restart = fn(timer);
- trace_hrtimer_expire_exit(timer);
- raw_spin_lock(&cpu_base->lock);
-
- /*
- * Note: We clear the CALLBACK bit after enqueue_hrtimer and
- * we do not reprogramm the event hardware. Happens either in
- * hrtimer_start_range_ns() or in hrtimer_interrupt()
- */
- if (restart != HRTIMER_NORESTART) {
- BUG_ON(timer->state != HRTIMER_STATE_CALLBACK);
- enqueue_hrtimer(timer, base);
- }
-
- WARN_ON_ONCE(!(timer->state & HRTIMER_STATE_CALLBACK));
-
- timer->state &= ~HRTIMER_STATE_CALLBACK;
-}
-
-#ifdef CONFIG_HIGH_RES_TIMERS
-
-/*
- * High resolution timer interrupt
- * Called with interrupts disabled
- */
-void hrtimer_interrupt(struct clock_event_device *dev)
-{
- struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
- ktime_t expires_next, now, entry_time, delta;
- int i, retries = 0;
-
- BUG_ON(!cpu_base->hres_active);
- cpu_base->nr_events++;
- dev->next_event.tv64 = KTIME_MAX;
-
- raw_spin_lock(&cpu_base->lock);
- entry_time = now = hrtimer_update_base(cpu_base);
-retry:
- expires_next.tv64 = KTIME_MAX;
- /*
- * We set expires_next to KTIME_MAX here with cpu_base->lock
- * held to prevent that a timer is enqueued in our queue via
- * the migration code. This does not affect enqueueing of
- * timers which run their callback and need to be requeued on
- * this CPU.
- */
- cpu_base->expires_next.tv64 = KTIME_MAX;
-
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
- struct hrtimer_clock_base *base;
- struct timerqueue_node *node;
- ktime_t basenow;
-
- if (!(cpu_base->active_bases & (1 << i)))
- continue;
-
- base = cpu_base->clock_base + i;
- basenow = ktime_add(now, base->offset);
-
- while ((node = timerqueue_getnext(&base->active))) {
- struct hrtimer *timer;
-
- timer = container_of(node, struct hrtimer, node);
-
- /*
- * The immediate goal for using the softexpires is
- * minimizing wakeups, not running timers at the
- * earliest interrupt after their soft expiration.
- * This allows us to avoid using a Priority Search
- * Tree, which can answer a stabbing querry for
- * overlapping intervals and instead use the simple
- * BST we already have.
- * We don't add extra wakeups by delaying timers that
- * are right-of a not yet expired timer, because that
- * timer will have to trigger a wakeup anyway.
- */
-
- if (basenow.tv64 < hrtimer_get_softexpires_tv64(timer)) {
- ktime_t expires;
-
- expires = ktime_sub(hrtimer_get_expires(timer),
- base->offset);
- if (expires.tv64 < 0)
- expires.tv64 = KTIME_MAX;
- if (expires.tv64 < expires_next.tv64)
- expires_next = expires;
- break;
- }
-
- __run_hrtimer(timer, &basenow);
- }
- }
-
- /*
- * Store the new expiry value so the migration code can verify
- * against it.
- */
- cpu_base->expires_next = expires_next;
- raw_spin_unlock(&cpu_base->lock);
-
- /* Reprogramming necessary ? */
- if (expires_next.tv64 == KTIME_MAX ||
- !tick_program_event(expires_next, 0)) {
- cpu_base->hang_detected = 0;
- return;
- }
-
- /*
- * The next timer was already expired due to:
- * - tracing
- * - long lasting callbacks
- * - being scheduled away when running in a VM
- *
- * We need to prevent that we loop forever in the hrtimer
- * interrupt routine. We give it 3 attempts to avoid
- * overreacting on some spurious event.
- *
- * Acquire base lock for updating the offsets and retrieving
- * the current time.
- */
- raw_spin_lock(&cpu_base->lock);
- now = hrtimer_update_base(cpu_base);
- cpu_base->nr_retries++;
- if (++retries < 3)
- goto retry;
- /*
- * Give the system a chance to do something else than looping
- * here. We stored the entry time, so we know exactly how long
- * we spent here. We schedule the next event this amount of
- * time away.
- */
- cpu_base->nr_hangs++;
- cpu_base->hang_detected = 1;
- raw_spin_unlock(&cpu_base->lock);
- delta = ktime_sub(now, entry_time);
- if (delta.tv64 > cpu_base->max_hang_time.tv64)
- cpu_base->max_hang_time = delta;
- /*
- * Limit it to a sensible value as we enforce a longer
- * delay. Give the CPU at least 100ms to catch up.
- */
- if (delta.tv64 > 100 * NSEC_PER_MSEC)
- expires_next = ktime_add_ns(now, 100 * NSEC_PER_MSEC);
- else
- expires_next = ktime_add(now, delta);
- tick_program_event(expires_next, 1);
- printk_once(KERN_WARNING "hrtimer: interrupt took %llu ns\n",
- ktime_to_ns(delta));
-}
-
-/*
- * local version of hrtimer_peek_ahead_timers() called with interrupts
- * disabled.
- */
-static void __hrtimer_peek_ahead_timers(void)
-{
- struct tick_device *td;
-
- if (!hrtimer_hres_active())
- return;
-
- td = &__get_cpu_var(tick_cpu_device);
- if (td && td->evtdev)
- hrtimer_interrupt(td->evtdev);
-}
-
-/**
- * hrtimer_peek_ahead_timers -- run soft-expired timers now
- *
- * hrtimer_peek_ahead_timers will peek at the timer queue of
- * the current cpu and check if there are any timers for which
- * the soft expires time has passed. If any such timers exist,
- * they are run immediately and then removed from the timer queue.
- *
- */
-void hrtimer_peek_ahead_timers(void)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- __hrtimer_peek_ahead_timers();
- local_irq_restore(flags);
-}
-
-static void run_hrtimer_softirq(struct softirq_action *h)
-{
- hrtimer_peek_ahead_timers();
-}
-
-#else /* CONFIG_HIGH_RES_TIMERS */
-
-static inline void __hrtimer_peek_ahead_timers(void) { }
-
-#endif /* !CONFIG_HIGH_RES_TIMERS */
-
-/*
- * Called from timer softirq every jiffy, expire hrtimers:
- *
- * For HRT its the fall back code to run the softirq in the timer
- * softirq context in case the hrtimer initialization failed or has
- * not been done yet.
- */
-void hrtimer_run_pending(void)
-{
- if (hrtimer_hres_active())
- return;
-
- /*
- * This _is_ ugly: We have to check in the softirq context,
- * whether we can switch to highres and / or nohz mode. The
- * clocksource switch happens in the timer interrupt with
- * xtime_lock held. Notification from there only sets the
- * check bit in the tick_oneshot code, otherwise we might
- * deadlock vs. xtime_lock.
- */
- if (tick_check_oneshot_change(!hrtimer_is_hres_enabled()))
- hrtimer_switch_to_hres();
-}
-
-/*
- * Called from hardirq context every jiffy
- */
-void hrtimer_run_queues(void)
-{
- struct timerqueue_node *node;
- struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
- struct hrtimer_clock_base *base;
- int index, gettime = 1;
-
- if (hrtimer_hres_active())
- return;
-
- for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
- base = &cpu_base->clock_base[index];
- if (!timerqueue_getnext(&base->active))
- continue;
-
- if (gettime) {
- hrtimer_get_softirq_time(cpu_base);
- gettime = 0;
- }
-
- raw_spin_lock(&cpu_base->lock);
-
- while ((node = timerqueue_getnext(&base->active))) {
- struct hrtimer *timer;
-
- timer = container_of(node, struct hrtimer, node);
- if (base->softirq_time.tv64 <=
- hrtimer_get_expires_tv64(timer))
- break;
-
- __run_hrtimer(timer, &base->softirq_time);
- }
- raw_spin_unlock(&cpu_base->lock);
- }
-}
-
-/*
- * Sleep related functions:
- */
-static enum hrtimer_restart 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, struct task_struct *task)
-{
- sl->timer.function = hrtimer_wakeup;
- sl->task = task;
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
-
-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_expires(&t->timer, mode);
- if (!hrtimer_active(&t->timer))
- t->task = NULL;
-
- if (likely(t->task))
- freezable_schedule();
-
- hrtimer_cancel(&t->timer);
- mode = HRTIMER_MODE_ABS;
-
- } while (t->task && !signal_pending(current));
-
- __set_current_state(TASK_RUNNING);
-
- return t->task == NULL;
-}
-
-static int update_rmtp(struct hrtimer *timer, struct timespec __user *rmtp)
-{
- struct timespec rmt;
- ktime_t rem;
-
- rem = hrtimer_expires_remaining(timer);
- if (rem.tv64 <= 0)
- return 0;
- rmt = ktime_to_timespec(rem);
-
- if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
- return -EFAULT;
-
- return 1;
-}
-
-long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
-{
- struct hrtimer_sleeper t;
- struct timespec __user *rmtp;
- int ret = 0;
-
- hrtimer_init_on_stack(&t.timer, restart->nanosleep.clockid,
- HRTIMER_MODE_ABS);
- hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
-
- if (do_nanosleep(&t, HRTIMER_MODE_ABS))
- goto out;
-
- rmtp = restart->nanosleep.rmtp;
- if (rmtp) {
- ret = update_rmtp(&t.timer, rmtp);
- if (ret <= 0)
- goto out;
- }
-
- /* The other values in restart are already filled in */
- ret = -ERESTART_RESTARTBLOCK;
-out:
- destroy_hrtimer_on_stack(&t.timer);
- return ret;
-}
-
-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;
- int ret = 0;
- unsigned long slack;
-
- slack = current->timer_slack_ns;
- if (dl_task(current) || rt_task(current))
- slack = 0;
-
- hrtimer_init_on_stack(&t.timer, clockid, mode);
- hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack);
- if (do_nanosleep(&t, mode))
- goto out;
-
- /* Absolute timers do not update the rmtp value and restart: */
- if (mode == HRTIMER_MODE_ABS) {
- ret = -ERESTARTNOHAND;
- goto out;
- }
-
- if (rmtp) {
- ret = update_rmtp(&t.timer, rmtp);
- if (ret <= 0)
- goto out;
- }
-
- restart = &current_thread_info()->restart_block;
- restart->fn = hrtimer_nanosleep_restart;
- restart->nanosleep.clockid = t.timer.base->clockid;
- restart->nanosleep.rmtp = rmtp;
- restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);
-
- ret = -ERESTART_RESTARTBLOCK;
-out:
- destroy_hrtimer_on_stack(&t.timer);
- return ret;
-}
-
-SYSCALL_DEFINE2(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_MODE_REL, CLOCK_MONOTONIC);
-}
-
-/*
- * Functions related to boot-time initialization:
- */
-static void init_hrtimers_cpu(int cpu)
-{
- struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
- int i;
-
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
- cpu_base->clock_base[i].cpu_base = cpu_base;
- timerqueue_init_head(&cpu_base->clock_base[i].active);
- }
-
- hrtimer_init_hres(cpu_base);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
- struct hrtimer_clock_base *new_base)
-{
- struct hrtimer *timer;
- struct timerqueue_node *node;
-
- while ((node = timerqueue_getnext(&old_base->active))) {
- timer = container_of(node, struct hrtimer, node);
- BUG_ON(hrtimer_callback_running(timer));
- debug_deactivate(timer);
-
- /*
- * Mark it as STATE_MIGRATE not INACTIVE otherwise the
- * timer could be seen as !active and just vanish away
- * under us on another CPU
- */
- __remove_hrtimer(timer, old_base, HRTIMER_STATE_MIGRATE, 0);
- timer->base = new_base;
- /*
- * Enqueue the timers on the new cpu. This does not
- * reprogram the event device in case the timer
- * expires before the earliest on this CPU, but we run
- * hrtimer_interrupt after we migrated everything to
- * sort out already expired timers and reprogram the
- * event device.
- */
- enqueue_hrtimer(timer, new_base);
-
- /* Clear the migration state bit */
- timer->state &= ~HRTIMER_STATE_MIGRATE;
- }
-}
-
-static void migrate_hrtimers(int scpu)
-{
- struct hrtimer_cpu_base *old_base, *new_base;
- int i;
-
- BUG_ON(cpu_online(scpu));
- tick_cancel_sched_timer(scpu);
-
- local_irq_disable();
- old_base = &per_cpu(hrtimer_bases, scpu);
- new_base = &__get_cpu_var(hrtimer_bases);
- /*
- * The caller is globally serialized and nobody else
- * takes two locks at once, deadlock is not possible.
- */
- raw_spin_lock(&new_base->lock);
- raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
-
- for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
- migrate_hrtimer_list(&old_base->clock_base[i],
- &new_base->clock_base[i]);
- }
-
- raw_spin_unlock(&old_base->lock);
- raw_spin_unlock(&new_base->lock);
-
- /* Check, if we got expired work to do */
- __hrtimer_peek_ahead_timers();
- local_irq_enable();
-}
-
-#endif /* CONFIG_HOTPLUG_CPU */
-
-static int hrtimer_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- int scpu = (long)hcpu;
-
- switch (action) {
-
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- init_hrtimers_cpu(scpu);
- break;
-
-#ifdef CONFIG_HOTPLUG_CPU
- case CPU_DYING:
- case CPU_DYING_FROZEN:
- clockevents_notify(CLOCK_EVT_NOTIFY_CPU_DYING, &scpu);
- break;
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- {
- clockevents_notify(CLOCK_EVT_NOTIFY_CPU_DEAD, &scpu);
- migrate_hrtimers(scpu);
- 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);
-#ifdef CONFIG_HIGH_RES_TIMERS
- open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq);
-#endif
-}
-
-/**
- * schedule_hrtimeout_range_clock - sleep until timeout
- * @expires: timeout value (ktime_t)
- * @delta: slack in expires timeout (ktime_t)
- * @mode: timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
- * @clock: timer clock, CLOCK_MONOTONIC or CLOCK_REALTIME
- */
-int __sched
-schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
- const enum hrtimer_mode mode, int clock)
-{
- struct hrtimer_sleeper t;
-
- /*
- * Optimize when a zero timeout value is given. It does not
- * matter whether this is an absolute or a relative time.
- */
- if (expires && !expires->tv64) {
- __set_current_state(TASK_RUNNING);
- return 0;
- }
-
- /*
- * A NULL parameter means "infinite"
- */
- if (!expires) {
- schedule();
- __set_current_state(TASK_RUNNING);
- return -EINTR;
- }
-
- hrtimer_init_on_stack(&t.timer, clock, mode);
- hrtimer_set_expires_range_ns(&t.timer, *expires, delta);
-
- hrtimer_init_sleeper(&t, current);
-
- hrtimer_start_expires(&t.timer, mode);
- if (!hrtimer_active(&t.timer))
- t.task = NULL;
-
- if (likely(t.task))
- schedule();
-
- hrtimer_cancel(&t.timer);
- destroy_hrtimer_on_stack(&t.timer);
-
- __set_current_state(TASK_RUNNING);
-
- return !t.task ? 0 : -EINTR;
-}
-
-/**
- * schedule_hrtimeout_range - sleep until timeout
- * @expires: timeout value (ktime_t)
- * @delta: slack in expires timeout (ktime_t)
- * @mode: timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
- *
- * Make the current task sleep until the given expiry time has
- * elapsed. The routine will return immediately unless
- * the current task state has been set (see set_current_state()).
- *
- * The @delta argument gives the kernel the freedom to schedule the
- * actual wakeup to a time that is both power and performance friendly.
- * The kernel give the normal best effort behavior for "@expires+@delta",
- * but may decide to fire the timer earlier, but no earlier than @expires.
- *
- * You can set the task state as follows -
- *
- * %TASK_UNINTERRUPTIBLE - at least @timeout time is guaranteed to
- * pass before the routine returns.
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task.
- *
- * The current task state is guaranteed to be TASK_RUNNING when this
- * routine returns.
- *
- * Returns 0 when the timer has expired otherwise -EINTR
- */
-int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
- const enum hrtimer_mode mode)
-{
- return schedule_hrtimeout_range_clock(expires, delta, mode,
- CLOCK_MONOTONIC);
-}
-EXPORT_SYMBOL_GPL(schedule_hrtimeout_range);
-
-/**
- * schedule_hrtimeout - sleep until timeout
- * @expires: timeout value (ktime_t)
- * @mode: timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
- *
- * Make the current task sleep until the given expiry time has
- * elapsed. The routine will return immediately unless
- * the current task state has been set (see set_current_state()).
- *
- * You can set the task state as follows -
- *
- * %TASK_UNINTERRUPTIBLE - at least @timeout time is guaranteed to
- * pass before the routine returns.
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task.
- *
- * The current task state is guaranteed to be TASK_RUNNING when this
- * routine returns.
- *
- * Returns 0 when the timer has expired otherwise -EINTR
- */
-int __sched schedule_hrtimeout(ktime_t *expires,
- const enum hrtimer_mode mode)
-{
- return schedule_hrtimeout_range(expires, 0, mode);
-}
-EXPORT_SYMBOL_GPL(schedule_hrtimeout);