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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/timer.c
parent58394271c610e9c65dd0165a1c1f6dec75dc5f3e (diff)
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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/timer.c')
-rw-r--r--kernel/timer.c1734
1 files changed, 0 insertions, 1734 deletions
diff --git a/kernel/timer.c b/kernel/timer.c
deleted file mode 100644
index 3bb01a323b2a..000000000000
--- a/kernel/timer.c
+++ /dev/null
@@ -1,1734 +0,0 @@
-/*
- * linux/kernel/timer.c
- *
- * Kernel internal timers
- *
- * Copyright (C) 1991, 1992 Linus Torvalds
- *
- * 1997-01-28 Modified by Finn Arne Gangstad to make timers scale better.
- *
- * 1997-09-10 Updated NTP code according to technical memorandum Jan '96
- * "A Kernel Model for Precision Timekeeping" by Dave Mills
- * 1998-12-24 Fixed a xtime SMP race (we need the xtime_lock rw spinlock to
- * serialize accesses to xtime/lost_ticks).
- * Copyright (C) 1998 Andrea Arcangeli
- * 1999-03-10 Improved NTP compatibility by Ulrich Windl
- * 2002-05-31 Move sys_sysinfo here and make its locking sane, Robert Love
- * 2000-10-05 Implemented scalable SMP per-CPU timer handling.
- * Copyright (C) 2000, 2001, 2002 Ingo Molnar
- * Designed by David S. Miller, Alexey Kuznetsov and Ingo Molnar
- */
-
-#include <linux/kernel_stat.h>
-#include <linux/export.h>
-#include <linux/interrupt.h>
-#include <linux/percpu.h>
-#include <linux/init.h>
-#include <linux/mm.h>
-#include <linux/swap.h>
-#include <linux/pid_namespace.h>
-#include <linux/notifier.h>
-#include <linux/thread_info.h>
-#include <linux/time.h>
-#include <linux/jiffies.h>
-#include <linux/posix-timers.h>
-#include <linux/cpu.h>
-#include <linux/syscalls.h>
-#include <linux/delay.h>
-#include <linux/tick.h>
-#include <linux/kallsyms.h>
-#include <linux/irq_work.h>
-#include <linux/sched.h>
-#include <linux/sched/sysctl.h>
-#include <linux/slab.h>
-#include <linux/compat.h>
-
-#include <asm/uaccess.h>
-#include <asm/unistd.h>
-#include <asm/div64.h>
-#include <asm/timex.h>
-#include <asm/io.h>
-
-#define CREATE_TRACE_POINTS
-#include <trace/events/timer.h>
-
-__visible u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
-
-EXPORT_SYMBOL(jiffies_64);
-
-/*
- * per-CPU timer vector definitions:
- */
-#define TVN_BITS (CONFIG_BASE_SMALL ? 4 : 6)
-#define TVR_BITS (CONFIG_BASE_SMALL ? 6 : 8)
-#define TVN_SIZE (1 << TVN_BITS)
-#define TVR_SIZE (1 << TVR_BITS)
-#define TVN_MASK (TVN_SIZE - 1)
-#define TVR_MASK (TVR_SIZE - 1)
-#define MAX_TVAL ((unsigned long)((1ULL << (TVR_BITS + 4*TVN_BITS)) - 1))
-
-struct tvec {
- struct list_head vec[TVN_SIZE];
-};
-
-struct tvec_root {
- struct list_head vec[TVR_SIZE];
-};
-
-struct tvec_base {
- spinlock_t lock;
- struct timer_list *running_timer;
- unsigned long timer_jiffies;
- unsigned long next_timer;
- unsigned long active_timers;
- unsigned long all_timers;
- struct tvec_root tv1;
- struct tvec tv2;
- struct tvec tv3;
- struct tvec tv4;
- struct tvec tv5;
-} ____cacheline_aligned;
-
-struct tvec_base boot_tvec_bases;
-EXPORT_SYMBOL(boot_tvec_bases);
-static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases;
-
-/* Functions below help us manage 'deferrable' flag */
-static inline unsigned int tbase_get_deferrable(struct tvec_base *base)
-{
- return ((unsigned int)(unsigned long)base & TIMER_DEFERRABLE);
-}
-
-static inline unsigned int tbase_get_irqsafe(struct tvec_base *base)
-{
- return ((unsigned int)(unsigned long)base & TIMER_IRQSAFE);
-}
-
-static inline struct tvec_base *tbase_get_base(struct tvec_base *base)
-{
- return ((struct tvec_base *)((unsigned long)base & ~TIMER_FLAG_MASK));
-}
-
-static inline void
-timer_set_base(struct timer_list *timer, struct tvec_base *new_base)
-{
- unsigned long flags = (unsigned long)timer->base & TIMER_FLAG_MASK;
-
- timer->base = (struct tvec_base *)((unsigned long)(new_base) | flags);
-}
-
-static unsigned long round_jiffies_common(unsigned long j, int cpu,
- bool force_up)
-{
- int rem;
- unsigned long original = j;
-
- /*
- * We don't want all cpus firing their timers at once hitting the
- * same lock or cachelines, so we skew each extra cpu with an extra
- * 3 jiffies. This 3 jiffies came originally from the mm/ code which
- * already did this.
- * The skew is done by adding 3*cpunr, then round, then subtract this
- * extra offset again.
- */
- j += cpu * 3;
-
- rem = j % HZ;
-
- /*
- * If the target jiffie is just after a whole second (which can happen
- * due to delays of the timer irq, long irq off times etc etc) then
- * we should round down to the whole second, not up. Use 1/4th second
- * as cutoff for this rounding as an extreme upper bound for this.
- * But never round down if @force_up is set.
- */
- if (rem < HZ/4 && !force_up) /* round down */
- j = j - rem;
- else /* round up */
- j = j - rem + HZ;
-
- /* now that we have rounded, subtract the extra skew again */
- j -= cpu * 3;
-
- /*
- * Make sure j is still in the future. Otherwise return the
- * unmodified value.
- */
- return time_is_after_jiffies(j) ? j : original;
-}
-
-/**
- * __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)
- * 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.
- *
- * By rounding these timers to whole seconds, all such timers will fire
- * 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 exact rounding is skewed for each processor to avoid all
- * 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.
- */
-unsigned long __round_jiffies(unsigned long j, int cpu)
-{
- return round_jiffies_common(j, cpu, false);
-}
-EXPORT_SYMBOL_GPL(__round_jiffies);
-
-/**
- * __round_jiffies_relative - function to round jiffies to a full second
- * @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)
- * 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.
- *
- * By rounding these timers to whole seconds, all such timers will fire
- * 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 exact rounding is skewed for each processor to avoid all
- * 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.
- */
-unsigned long __round_jiffies_relative(unsigned long j, int cpu)
-{
- unsigned long j0 = jiffies;
-
- /* Use j0 because jiffies might change while we run */
- return round_jiffies_common(j + j0, cpu, false) - j0;
-}
-EXPORT_SYMBOL_GPL(__round_jiffies_relative);
-
-/**
- * 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)
- * 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.
- *
- * By rounding these timers to whole seconds, all such timers will fire
- * 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.
- */
-unsigned long round_jiffies(unsigned long j)
-{
- return round_jiffies_common(j, raw_smp_processor_id(), false);
-}
-EXPORT_SYMBOL_GPL(round_jiffies);
-
-/**
- * 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)
- * 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.
- *
- * By rounding these timers to whole seconds, all such timers will fire
- * 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.
- */
-unsigned long round_jiffies_relative(unsigned long j)
-{
- return __round_jiffies_relative(j, raw_smp_processor_id());
-}
-EXPORT_SYMBOL_GPL(round_jiffies_relative);
-
-/**
- * __round_jiffies_up - function to round jiffies up to a full second
- * @j: the time in (absolute) jiffies that should be rounded
- * @cpu: the processor number on which the timeout will happen
- *
- * This is the same as __round_jiffies() except that it will never
- * round down. This is useful for timeouts for which the exact time
- * of firing does not matter too much, as long as they don't fire too
- * early.
- */
-unsigned long __round_jiffies_up(unsigned long j, int cpu)
-{
- return round_jiffies_common(j, cpu, true);
-}
-EXPORT_SYMBOL_GPL(__round_jiffies_up);
-
-/**
- * __round_jiffies_up_relative - function to round jiffies up to a full second
- * @j: the time in (relative) jiffies that should be rounded
- * @cpu: the processor number on which the timeout will happen
- *
- * This is the same as __round_jiffies_relative() except that it will never
- * round down. This is useful for timeouts for which the exact time
- * of firing does not matter too much, as long as they don't fire too
- * early.
- */
-unsigned long __round_jiffies_up_relative(unsigned long j, int cpu)
-{
- unsigned long j0 = jiffies;
-
- /* Use j0 because jiffies might change while we run */
- return round_jiffies_common(j + j0, cpu, true) - j0;
-}
-EXPORT_SYMBOL_GPL(__round_jiffies_up_relative);
-
-/**
- * round_jiffies_up - function to round jiffies up to a full second
- * @j: the time in (absolute) jiffies that should be rounded
- *
- * This is the same as round_jiffies() except that it will never
- * round down. This is useful for timeouts for which the exact time
- * of firing does not matter too much, as long as they don't fire too
- * early.
- */
-unsigned long round_jiffies_up(unsigned long j)
-{
- return round_jiffies_common(j, raw_smp_processor_id(), true);
-}
-EXPORT_SYMBOL_GPL(round_jiffies_up);
-
-/**
- * round_jiffies_up_relative - function to round jiffies up to a full second
- * @j: the time in (relative) jiffies that should be rounded
- *
- * This is the same as round_jiffies_relative() except that it will never
- * round down. This is useful for timeouts for which the exact time
- * of firing does not matter too much, as long as they don't fire too
- * early.
- */
-unsigned long round_jiffies_up_relative(unsigned long j)
-{
- return __round_jiffies_up_relative(j, raw_smp_processor_id());
-}
-EXPORT_SYMBOL_GPL(round_jiffies_up_relative);
-
-/**
- * set_timer_slack - set the allowed slack for a timer
- * @timer: the timer to be modified
- * @slack_hz: the amount of time (in jiffies) allowed for rounding
- *
- * Set the amount of time, in jiffies, that a certain timer has
- * in terms of slack. By setting this value, the timer subsystem
- * will schedule the actual timer somewhere between
- * the time mod_timer() asks for, and that time plus the slack.
- *
- * By setting the slack to -1, a percentage of the delay is used
- * instead.
- */
-void set_timer_slack(struct timer_list *timer, int slack_hz)
-{
- timer->slack = slack_hz;
-}
-EXPORT_SYMBOL_GPL(set_timer_slack);
-
-/*
- * If the list is empty, catch up ->timer_jiffies to the current time.
- * The caller must hold the tvec_base lock. Returns true if the list
- * was empty and therefore ->timer_jiffies was updated.
- */
-static bool catchup_timer_jiffies(struct tvec_base *base)
-{
- if (!base->all_timers) {
- base->timer_jiffies = jiffies;
- return true;
- }
- return false;
-}
-
-static void
-__internal_add_timer(struct tvec_base *base, struct timer_list *timer)
-{
- unsigned long expires = timer->expires;
- unsigned long idx = expires - base->timer_jiffies;
- struct list_head *vec;
-
- if (idx < TVR_SIZE) {
- int i = expires & TVR_MASK;
- vec = base->tv1.vec + i;
- } else if (idx < 1 << (TVR_BITS + TVN_BITS)) {
- int i = (expires >> TVR_BITS) & TVN_MASK;
- vec = base->tv2.vec + i;
- } else if (idx < 1 << (TVR_BITS + 2 * TVN_BITS)) {
- int i = (expires >> (TVR_BITS + TVN_BITS)) & TVN_MASK;
- vec = base->tv3.vec + i;
- } else if (idx < 1 << (TVR_BITS + 3 * TVN_BITS)) {
- int i = (expires >> (TVR_BITS + 2 * TVN_BITS)) & TVN_MASK;
- vec = base->tv4.vec + i;
- } else if ((signed long) idx < 0) {
- /*
- * Can happen if you add a timer with expires == jiffies,
- * or you set a timer to go off in the past
- */
- vec = base->tv1.vec + (base->timer_jiffies & TVR_MASK);
- } else {
- int i;
- /* If the timeout is larger than MAX_TVAL (on 64-bit
- * architectures or with CONFIG_BASE_SMALL=1) then we
- * use the maximum timeout.
- */
- if (idx > MAX_TVAL) {
- idx = MAX_TVAL;
- expires = idx + base->timer_jiffies;
- }
- i = (expires >> (TVR_BITS + 3 * TVN_BITS)) & TVN_MASK;
- vec = base->tv5.vec + i;
- }
- /*
- * Timers are FIFO:
- */
- list_add_tail(&timer->entry, vec);
-}
-
-static void internal_add_timer(struct tvec_base *base, struct timer_list *timer)
-{
- (void)catchup_timer_jiffies(base);
- __internal_add_timer(base, timer);
- /*
- * Update base->active_timers and base->next_timer
- */
- if (!tbase_get_deferrable(timer->base)) {
- if (!base->active_timers++ ||
- time_before(timer->expires, base->next_timer))
- base->next_timer = timer->expires;
- }
- base->all_timers++;
-}
-
-#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;
-}
-
-static void timer_stats_account_timer(struct timer_list *timer)
-{
- unsigned int flag = 0;
-
- if (likely(!timer->start_site))
- return;
- if (unlikely(tbase_get_deferrable(timer->base)))
- flag |= TIMER_STATS_FLAG_DEFERRABLE;
-
- timer_stats_update_stats(timer, timer->start_pid, timer->start_site,
- timer->function, timer->start_comm, flag);
-}
-
-#else
-static void timer_stats_account_timer(struct timer_list *timer) {}
-#endif
-
-#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
-
-static struct debug_obj_descr timer_debug_descr;
-
-static void *timer_debug_hint(void *addr)
-{
- return ((struct timer_list *) addr)->function;
-}
-
-/*
- * fixup_init is called when:
- * - an active object is initialized
- */
-static int timer_fixup_init(void *addr, enum debug_obj_state state)
-{
- struct timer_list *timer = addr;
-
- switch (state) {
- case ODEBUG_STATE_ACTIVE:
- del_timer_sync(timer);
- debug_object_init(timer, &timer_debug_descr);
- return 1;
- default:
- return 0;
- }
-}
-
-/* Stub timer callback for improperly used timers. */
-static void stub_timer(unsigned long data)
-{
- WARN_ON(1);
-}
-
-/*
- * fixup_activate is called when:
- * - an active object is activated
- * - an unknown object is activated (might be a statically initialized object)
- */
-static int timer_fixup_activate(void *addr, enum debug_obj_state state)
-{
- struct timer_list *timer = addr;
-
- switch (state) {
-
- case ODEBUG_STATE_NOTAVAILABLE:
- /*
- * This is not really a fixup. The timer was
- * statically initialized. We just make sure that it
- * is tracked in the object tracker.
- */
- if (timer->entry.next == NULL &&
- timer->entry.prev == TIMER_ENTRY_STATIC) {
- debug_object_init(timer, &timer_debug_descr);
- debug_object_activate(timer, &timer_debug_descr);
- return 0;
- } else {
- setup_timer(timer, stub_timer, 0);
- return 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 timer_fixup_free(void *addr, enum debug_obj_state state)
-{
- struct timer_list *timer = addr;
-
- switch (state) {
- case ODEBUG_STATE_ACTIVE:
- del_timer_sync(timer);
- debug_object_free(timer, &timer_debug_descr);
- return 1;
- default:
- return 0;
- }
-}
-
-/*
- * fixup_assert_init is called when:
- * - an untracked/uninit-ed object is found
- */
-static int timer_fixup_assert_init(void *addr, enum debug_obj_state state)
-{
- struct timer_list *timer = addr;
-
- switch (state) {
- case ODEBUG_STATE_NOTAVAILABLE:
- if (timer->entry.prev == TIMER_ENTRY_STATIC) {
- /*
- * This is not really a fixup. The timer was
- * statically initialized. We just make sure that it
- * is tracked in the object tracker.
- */
- debug_object_init(timer, &timer_debug_descr);
- return 0;
- } else {
- setup_timer(timer, stub_timer, 0);
- return 1;
- }
- default:
- return 0;
- }
-}
-
-static struct debug_obj_descr timer_debug_descr = {
- .name = "timer_list",
- .debug_hint = timer_debug_hint,
- .fixup_init = timer_fixup_init,
- .fixup_activate = timer_fixup_activate,
- .fixup_free = timer_fixup_free,
- .fixup_assert_init = timer_fixup_assert_init,
-};
-
-static inline void debug_timer_init(struct timer_list *timer)
-{
- debug_object_init(timer, &timer_debug_descr);
-}
-
-static inline void debug_timer_activate(struct timer_list *timer)
-{
- debug_object_activate(timer, &timer_debug_descr);
-}
-
-static inline void debug_timer_deactivate(struct timer_list *timer)
-{
- debug_object_deactivate(timer, &timer_debug_descr);
-}
-
-static inline void debug_timer_free(struct timer_list *timer)
-{
- debug_object_free(timer, &timer_debug_descr);
-}
-
-static inline void debug_timer_assert_init(struct timer_list *timer)
-{
- debug_object_assert_init(timer, &timer_debug_descr);
-}
-
-static void do_init_timer(struct timer_list *timer, unsigned int flags,
- const char *name, struct lock_class_key *key);
-
-void init_timer_on_stack_key(struct timer_list *timer, unsigned int flags,
- const char *name, struct lock_class_key *key)
-{
- debug_object_init_on_stack(timer, &timer_debug_descr);
- do_init_timer(timer, flags, name, key);
-}
-EXPORT_SYMBOL_GPL(init_timer_on_stack_key);
-
-void destroy_timer_on_stack(struct timer_list *timer)
-{
- debug_object_free(timer, &timer_debug_descr);
-}
-EXPORT_SYMBOL_GPL(destroy_timer_on_stack);
-
-#else
-static inline void debug_timer_init(struct timer_list *timer) { }
-static inline void debug_timer_activate(struct timer_list *timer) { }
-static inline void debug_timer_deactivate(struct timer_list *timer) { }
-static inline void debug_timer_assert_init(struct timer_list *timer) { }
-#endif
-
-static inline void debug_init(struct timer_list *timer)
-{
- debug_timer_init(timer);
- trace_timer_init(timer);
-}
-
-static inline void
-debug_activate(struct timer_list *timer, unsigned long expires)
-{
- debug_timer_activate(timer);
- trace_timer_start(timer, expires);
-}
-
-static inline void debug_deactivate(struct timer_list *timer)
-{
- debug_timer_deactivate(timer);
- trace_timer_cancel(timer);
-}
-
-static inline void debug_assert_init(struct timer_list *timer)
-{
- debug_timer_assert_init(timer);
-}
-
-static void do_init_timer(struct timer_list *timer, unsigned int flags,
- const char *name, struct lock_class_key *key)
-{
- struct tvec_base *base = __raw_get_cpu_var(tvec_bases);
-
- timer->entry.next = NULL;
- timer->base = (void *)((unsigned long)base | flags);
- timer->slack = -1;
-#ifdef CONFIG_TIMER_STATS
- timer->start_site = NULL;
- timer->start_pid = -1;
- memset(timer->start_comm, 0, TASK_COMM_LEN);
-#endif
- lockdep_init_map(&timer->lockdep_map, name, key, 0);
-}
-
-/**
- * init_timer_key - initialize a timer
- * @timer: the timer to be initialized
- * @flags: timer flags
- * @name: name of the timer
- * @key: lockdep class key of the fake lock used for tracking timer
- * sync lock dependencies
- *
- * init_timer_key() must be done to a timer prior calling *any* of the
- * other timer functions.
- */
-void init_timer_key(struct timer_list *timer, unsigned int flags,
- const char *name, struct lock_class_key *key)
-{
- debug_init(timer);
- do_init_timer(timer, flags, name, key);
-}
-EXPORT_SYMBOL(init_timer_key);
-
-static inline void detach_timer(struct timer_list *timer, bool clear_pending)
-{
- struct list_head *entry = &timer->entry;
-
- debug_deactivate(timer);
-
- __list_del(entry->prev, entry->next);
- if (clear_pending)
- entry->next = NULL;
- entry->prev = LIST_POISON2;
-}
-
-static inline void
-detach_expired_timer(struct timer_list *timer, struct tvec_base *base)
-{
- detach_timer(timer, true);
- if (!tbase_get_deferrable(timer->base))
- base->active_timers--;
- base->all_timers--;
- (void)catchup_timer_jiffies(base);
-}
-
-static int detach_if_pending(struct timer_list *timer, struct tvec_base *base,
- bool clear_pending)
-{
- if (!timer_pending(timer))
- return 0;
-
- detach_timer(timer, clear_pending);
- if (!tbase_get_deferrable(timer->base)) {
- base->active_timers--;
- if (timer->expires == base->next_timer)
- base->next_timer = base->timer_jiffies;
- }
- base->all_timers--;
- (void)catchup_timer_jiffies(base);
- return 1;
-}
-
-/*
- * We are using hashed locking: holding per_cpu(tvec_bases).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 ->tvX lists.
- *
- * 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 tvec_base *lock_timer_base(struct timer_list *timer,
- unsigned long *flags)
- __acquires(timer->base->lock)
-{
- struct tvec_base *base;
-
- for (;;) {
- struct tvec_base *prelock_base = timer->base;
- base = tbase_get_base(prelock_base);
- if (likely(base != NULL)) {
- spin_lock_irqsave(&base->lock, *flags);
- if (likely(prelock_base == timer->base))
- return base;
- /* The timer has migrated to another CPU */
- spin_unlock_irqrestore(&base->lock, *flags);
- }
- cpu_relax();
- }
-}
-
-static inline int
-__mod_timer(struct timer_list *timer, unsigned long expires,
- bool pending_only, int pinned)
-{
- struct tvec_base *base, *new_base;
- unsigned long flags;
- int ret = 0 , cpu;
-
- timer_stats_timer_set_start_info(timer);
- BUG_ON(!timer->function);
-
- base = lock_timer_base(timer, &flags);
-
- ret = detach_if_pending(timer, base, false);
- if (!ret && pending_only)
- goto out_unlock;
-
- debug_activate(timer, expires);
-
- cpu = get_nohz_timer_target(pinned);
- new_base = per_cpu(tvec_bases, cpu);
-
- 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,
- * otherwise del_timer_sync() can't detect that the timer's
- * handler yet has not finished. This also guarantees that
- * the timer is serialized wrt itself.
- */
- if (likely(base->running_timer != timer)) {
- /* See the comment in lock_timer_base() */
- timer_set_base(timer, NULL);
- spin_unlock(&base->lock);
- base = new_base;
- spin_lock(&base->lock);
- timer_set_base(timer, base);
- }
- }
-
- timer->expires = expires;
- internal_add_timer(base, timer);
-
-out_unlock:
- spin_unlock_irqrestore(&base->lock, flags);
-
- return ret;
-}
-
-/**
- * mod_timer_pending - modify a pending timer's timeout
- * @timer: the pending timer to be modified
- * @expires: new timeout in jiffies
- *
- * mod_timer_pending() is the same for pending timers as mod_timer(),
- * but will not re-activate and modify already deleted timers.
- *
- * It is useful for unserialized use of timers.
- */
-int mod_timer_pending(struct timer_list *timer, unsigned long expires)
-{
- return __mod_timer(timer, expires, true, TIMER_NOT_PINNED);
-}
-EXPORT_SYMBOL(mod_timer_pending);
-
-/*
- * Decide where to put the timer while taking the slack into account
- *
- * Algorithm:
- * 1) calculate the maximum (absolute) time
- * 2) calculate the highest bit where the expires and new max are different
- * 3) use this bit to make a mask
- * 4) use the bitmask to round down the maximum time, so that all last
- * bits are zeros
- */
-static inline
-unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
-{
- unsigned long expires_limit, mask;
- int bit;
-
- if (timer->slack >= 0) {
- expires_limit = expires + timer->slack;
- } else {
- long delta = expires - jiffies;
-
- if (delta < 256)
- return expires;
-
- expires_limit = expires + delta / 256;
- }
- mask = expires ^ expires_limit;
- if (mask == 0)
- return expires;
-
- bit = find_last_bit(&mask, BITS_PER_LONG);
-
- mask = (1UL << bit) - 1;
-
- expires_limit = expires_limit & ~(mask);
-
- return expires_limit;
-}
-
-/**
- * mod_timer - modify a timer's timeout
- * @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
- * active timer (if the timer is inactive it will be activated)
- *
- * mod_timer(timer, expires) is equivalent to:
- *
- * del_timer(timer); timer->expires = expires; add_timer(timer);
- *
- * Note that if there are multiple unserialized concurrent users of the
- * same timer, then mod_timer() is the only safe way to modify the timeout,
- * since add_timer() cannot modify an already running timer.
- *
- * The function returns whether it has modified a pending timer or not.
- * (ie. mod_timer() of an inactive timer returns 0, mod_timer() of an
- * active timer returns 1.)
- */
-int mod_timer(struct timer_list *timer, unsigned long expires)
-{
- expires = apply_slack(timer, expires);
-
- /*
- * This is a common optimization triggered by the
- * networking code - if the timer is re-modified
- * to be the same thing then just return:
- */
- if (timer_pending(timer) && timer->expires == expires)
- return 1;
-
- return __mod_timer(timer, expires, false, TIMER_NOT_PINNED);
-}
-EXPORT_SYMBOL(mod_timer);
-
-/**
- * mod_timer_pinned - modify a timer's timeout
- * @timer: the timer to be modified
- * @expires: new timeout in jiffies
- *
- * mod_timer_pinned() is a way to update the expire field of an
- * active timer (if the timer is inactive it will be activated)
- * and to ensure that the timer is scheduled on the current CPU.
- *
- * Note that this does not prevent the timer from being migrated
- * when the current CPU goes offline. If this is a problem for
- * you, use CPU-hotplug notifiers to handle it correctly, for
- * example, cancelling the timer when the corresponding CPU goes
- * offline.
- *
- * mod_timer_pinned(timer, expires) is equivalent to:
- *
- * del_timer(timer); timer->expires = expires; add_timer(timer);
- */
-int mod_timer_pinned(struct timer_list *timer, unsigned long expires)
-{
- if (timer->expires == expires && timer_pending(timer))
- return 1;
-
- return __mod_timer(timer, expires, false, TIMER_PINNED);
-}
-EXPORT_SYMBOL(mod_timer_pinned);
-
-/**
- * add_timer - start a timer
- * @timer: the timer to be added
- *
- * The kernel will do a ->function(->data) callback from the
- * timer interrupt at the ->expires point in the future. The
- * current time is 'jiffies'.
- *
- * The timer's ->expires, ->function (and if the handler uses it, ->data)
- * fields must be set prior calling this function.
- *
- * Timers with an ->expires field in the past will be executed in the next
- * timer tick.
- */
-void add_timer(struct timer_list *timer)
-{
- BUG_ON(timer_pending(timer));
- mod_timer(timer, timer->expires);
-}
-EXPORT_SYMBOL(add_timer);
-
-/**
- * add_timer_on - start a timer on a particular CPU
- * @timer: the timer to be added
- * @cpu: the CPU to start it on
- *
- * This is not very scalable on SMP. Double adds are not possible.
- */
-void add_timer_on(struct timer_list *timer, int cpu)
-{
- struct tvec_base *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_set_base(timer, base);
- debug_activate(timer, timer->expires);
- internal_add_timer(base, timer);
- /*
- * Check whether the other CPU is in dynticks mode and needs
- * to be triggered to reevaluate the timer wheel.
- * We are protected against the other CPU fiddling
- * with the timer by holding the timer base lock. This also
- * makes sure that a CPU on the way to stop its tick can not
- * evaluate the timer wheel.
- *
- * Spare the IPI for deferrable timers on idle targets though.
- * The next busy ticks will take care of it. Except full dynticks
- * require special care against races with idle_cpu(), lets deal
- * with that later.
- */
- if (!tbase_get_deferrable(timer->base) || tick_nohz_full_cpu(cpu))
- wake_up_nohz_cpu(cpu);
-
- spin_unlock_irqrestore(&base->lock, flags);
-}
-EXPORT_SYMBOL_GPL(add_timer_on);
-
-/**
- * del_timer - deactive a timer.
- * @timer: the timer to be deactivated
- *
- * del_timer() deactivates a timer - this works on both active and inactive
- * timers.
- *
- * The function returns whether it has deactivated a pending timer or not.
- * (ie. del_timer() of an inactive timer returns 0, del_timer() of an
- * active timer returns 1.)
- */
-int del_timer(struct timer_list *timer)
-{
- struct tvec_base *base;
- unsigned long flags;
- int ret = 0;
-
- debug_assert_init(timer);
-
- timer_stats_timer_clear_start_info(timer);
- if (timer_pending(timer)) {
- base = lock_timer_base(timer, &flags);
- ret = detach_if_pending(timer, base, true);
- spin_unlock_irqrestore(&base->lock, flags);
- }
-
- return ret;
-}
-EXPORT_SYMBOL(del_timer);
-
-/**
- * try_to_del_timer_sync - Try to deactivate a timer
- * @timer: timer do del
- *
- * This function tries to deactivate a timer. Upon successful (ret >= 0)
- * exit the timer is not queued and the handler is not running on any CPU.
- */
-int try_to_del_timer_sync(struct timer_list *timer)
-{
- struct tvec_base *base;
- unsigned long flags;
- int ret = -1;
-
- debug_assert_init(timer);
-
- base = lock_timer_base(timer, &flags);
-
- if (base->running_timer != timer) {
- timer_stats_timer_clear_start_info(timer);
- ret = detach_if_pending(timer, base, true);
- }
- spin_unlock_irqrestore(&base->lock, flags);
-
- return ret;
-}
-EXPORT_SYMBOL(try_to_del_timer_sync);
-
-#ifdef CONFIG_SMP
-/**
- * del_timer_sync - deactivate a timer and wait for the handler to finish.
- * @timer: the timer to be deactivated
- *
- * This function only differs from del_timer() on SMP: besides deactivating
- * the timer it also makes sure the handler has finished executing on other
- * CPUs.
- *
- * Synchronization rules: Callers must prevent restarting of the timer,
- * otherwise this function is meaningless. It must not be called from
- * interrupt contexts unless the timer is an irqsafe one. The caller must
- * not hold locks which would prevent completion of the timer's
- * handler. The timer's handler must not call add_timer_on(). Upon exit the
- * timer is not queued and the handler is not running on any CPU.
- *
- * Note: For !irqsafe timers, you must not hold locks that are held in
- * interrupt context while calling this function. Even if the lock has
- * nothing to do with the timer in question. Here's why:
- *
- * CPU0 CPU1
- * ---- ----
- * <SOFTIRQ>
- * call_timer_fn();
- * base->running_timer = mytimer;
- * spin_lock_irq(somelock);
- * <IRQ>
- * spin_lock(somelock);
- * del_timer_sync(mytimer);
- * while (base->running_timer == mytimer);
- *
- * Now del_timer_sync() will never return and never release somelock.
- * The interrupt on the other CPU is waiting to grab somelock but
- * it has interrupted the softirq that CPU0 is waiting to finish.
- *
- * The function returns whether it has deactivated a pending timer or not.
- */
-int del_timer_sync(struct timer_list *timer)
-{
-#ifdef CONFIG_LOCKDEP
- unsigned long flags;
-
- /*
- * If lockdep gives a backtrace here, please reference
- * the synchronization rules above.
- */
- local_irq_save(flags);
- lock_map_acquire(&timer->lockdep_map);
- lock_map_release(&timer->lockdep_map);
- local_irq_restore(flags);
-#endif
- /*
- * don't use it in hardirq context, because it
- * could lead to deadlock.
- */
- WARN_ON(in_irq() && !tbase_get_irqsafe(timer->base));
- for (;;) {
- int ret = try_to_del_timer_sync(timer);
- if (ret >= 0)
- return ret;
- cpu_relax();
- }
-}
-EXPORT_SYMBOL(del_timer_sync);
-#endif
-
-static int cascade(struct tvec_base *base, struct tvec *tv, int index)
-{
- /* cascade all the timers from tv up one level */
- struct timer_list *timer, *tmp;
- struct list_head tv_list;
-
- list_replace_init(tv->vec + index, &tv_list);
-
- /*
- * We are removing _all_ timers from the list, so we
- * don't have to detach them individually.
- */
- list_for_each_entry_safe(timer, tmp, &tv_list, entry) {
- BUG_ON(tbase_get_base(timer->base) != base);
- /* No accounting, while moving them */
- __internal_add_timer(base, timer);
- }
-
- return index;
-}
-
-static void call_timer_fn(struct timer_list *timer, void (*fn)(unsigned long),
- unsigned long data)
-{
- int count = preempt_count();
-
-#ifdef CONFIG_LOCKDEP
- /*
- * It is permissible to free the timer from inside the
- * function that is called from it, this we need to take into
- * account for lockdep too. To avoid bogus "held lock freed"
- * warnings as well as problems when looking into
- * timer->lockdep_map, make a copy and use that here.
- */
- struct lockdep_map lockdep_map;
-
- lockdep_copy_map(&lockdep_map, &timer->lockdep_map);
-#endif
- /*
- * Couple the lock chain with the lock chain at
- * del_timer_sync() by acquiring the lock_map around the fn()
- * call here and in del_timer_sync().
- */
- lock_map_acquire(&lockdep_map);
-
- trace_timer_expire_entry(timer);
- fn(data);
- trace_timer_expire_exit(timer);
-
- lock_map_release(&lockdep_map);
-
- if (count != preempt_count()) {
- WARN_ONCE(1, "timer: %pF preempt leak: %08x -> %08x\n",
- fn, count, preempt_count());
- /*
- * Restore the preempt count. That gives us a decent
- * chance to survive and extract information. If the
- * callback kept a lock held, bad luck, but not worse
- * than the BUG() we had.
- */
- preempt_count_set(count);
- }
-}
-
-#define INDEX(N) ((base->timer_jiffies >> (TVR_BITS + (N) * TVN_BITS)) & TVN_MASK)
-
-/**
- * __run_timers - run all expired timers (if any) on this CPU.
- * @base: the timer vector to be processed.
- *
- * This function cascades all vectors and executes all expired timer
- * vectors.
- */
-static inline void __run_timers(struct tvec_base *base)
-{
- struct timer_list *timer;
-
- spin_lock_irq(&base->lock);
- if (catchup_timer_jiffies(base)) {
- spin_unlock_irq(&base->lock);
- return;
- }
- while (time_after_eq(jiffies, base->timer_jiffies)) {
- struct list_head work_list;
- struct list_head *head = &work_list;
- int index = base->timer_jiffies & TVR_MASK;
-
- /*
- * Cascade timers:
- */
- if (!index &&
- (!cascade(base, &base->tv2, INDEX(0))) &&
- (!cascade(base, &base->tv3, INDEX(1))) &&
- !cascade(base, &base->tv4, INDEX(2)))
- cascade(base, &base->tv5, INDEX(3));
- ++base->timer_jiffies;
- list_replace_init(base->tv1.vec + index, head);
- while (!list_empty(head)) {
- void (*fn)(unsigned long);
- unsigned long data;
- bool irqsafe;
-
- timer = list_first_entry(head, struct timer_list,entry);
- fn = timer->function;
- data = timer->data;
- irqsafe = tbase_get_irqsafe(timer->base);
-
- timer_stats_account_timer(timer);
-
- base->running_timer = timer;
- detach_expired_timer(timer, base);
-
- if (irqsafe) {
- spin_unlock(&base->lock);
- call_timer_fn(timer, fn, data);
- spin_lock(&base->lock);
- } else {
- spin_unlock_irq(&base->lock);
- call_timer_fn(timer, fn, data);
- spin_lock_irq(&base->lock);
- }
- }
- }
- base->running_timer = NULL;
- spin_unlock_irq(&base->lock);
-}
-
-#ifdef CONFIG_NO_HZ_COMMON
-/*
- * Find out when the next timer event is due to happen. This
- * is used on S/390 to stop all activity when a CPU is idle.
- * This function needs to be called with interrupts disabled.
- */
-static unsigned long __next_timer_interrupt(struct tvec_base *base)
-{
- 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;
- struct tvec *varray[4];
-
- /* Look for timer events in tv1. */
- index = slot = timer_jiffies & TVR_MASK;
- do {
- list_for_each_entry(nte, base->tv1.vec + slot, entry) {
- if (tbase_get_deferrable(nte->base))
- continue;
-
- found = 1;
- expires = nte->expires;
- /* Look at the cascade bucket(s)? */
- if (!index || slot < index)
- goto cascade;
- return expires;
- }
- 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 (array = 0; array < 4; array++) {
- struct tvec *varp = varray[array];
-
- index = slot = timer_jiffies & TVN_MASK;
- do {
- list_for_each_entry(nte, varp->vec + slot, entry) {
- if (tbase_get_deferrable(nte->base))
- continue;
-
- found = 1;
- if (time_before(nte->expires, expires))
- expires = nte->expires;
- }
- /*
- * 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);
-
- if (index)
- timer_jiffies += TVN_SIZE - index;
- timer_jiffies >>= TVN_BITS;
- }
- return expires;
-}
-
-/*
- * Check, if the next hrtimer event is before the next timer wheel
- * event:
- */
-static unsigned long cmp_next_hrtimer_event(unsigned long now,
- unsigned long expires)
-{
- ktime_t hr_delta = hrtimer_get_next_event();
- struct timespec tsdelta;
- unsigned long delta;
-
- if (hr_delta.tv64 == KTIME_MAX)
- return expires;
-
- /*
- * Expired timer available, let it expire in the next tick
- */
- if (hr_delta.tv64 <= 0)
- return now + 1;
-
- tsdelta = ktime_to_timespec(hr_delta);
- delta = timespec_to_jiffies(&tsdelta);
-
- /*
- * Limit the delta to the max value, which is checked in
- * tick_nohz_stop_sched_tick():
- */
- if (delta > NEXT_TIMER_MAX_DELTA)
- delta = NEXT_TIMER_MAX_DELTA;
-
- /*
- * 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
- */
- if (delta < 1)
- delta = 1;
- now += delta;
- if (time_before(now, expires))
- return now;
- return expires;
-}
-
-/**
- * get_next_timer_interrupt - return the jiffy of the next pending timer
- * @now: current time (in jiffies)
- */
-unsigned long get_next_timer_interrupt(unsigned long now)
-{
- struct tvec_base *base = __this_cpu_read(tvec_bases);
- unsigned long expires = now + NEXT_TIMER_MAX_DELTA;
-
- /*
- * Pretend that there is no timer pending if the cpu is offline.
- * Possible pending timers will be migrated later to an active cpu.
- */
- if (cpu_is_offline(smp_processor_id()))
- return expires;
-
- spin_lock(&base->lock);
- if (base->active_timers) {
- if (time_before_eq(base->next_timer, base->timer_jiffies))
- base->next_timer = __next_timer_interrupt(base);
- expires = base->next_timer;
- }
- spin_unlock(&base->lock);
-
- if (time_before_eq(expires, now))
- return now;
-
- return cmp_next_hrtimer_event(now, expires);
-}
-#endif
-
-/*
- * Called from the timer interrupt handler to charge one tick to the current
- * process. user_tick is 1 if the tick is user time, 0 for system.
- */
-void update_process_times(int user_tick)
-{
- struct task_struct *p = current;
- int cpu = smp_processor_id();
-
- /* Note: this timer irq context must be accounted for as well. */
- account_process_tick(p, user_tick);
- run_local_timers();
- rcu_check_callbacks(cpu, user_tick);
-#ifdef CONFIG_IRQ_WORK
- if (in_irq())
- irq_work_run();
-#endif
- scheduler_tick();
- run_posix_cpu_timers(p);
-}
-
-/*
- * This function runs timers and the timer-tq in bottom half context.
- */
-static void run_timer_softirq(struct softirq_action *h)
-{
- struct tvec_base *base = __this_cpu_read(tvec_bases);
-
- hrtimer_run_pending();
-
- if (time_after_eq(jiffies, base->timer_jiffies))
- __run_timers(base);
-}
-
-/*
- * Called by the local, per-CPU timer interrupt on SMP.
- */
-void run_local_timers(void)
-{
- hrtimer_run_queues();
- raise_softirq(TIMER_SOFTIRQ);
-}
-
-#ifdef __ARCH_WANT_SYS_ALARM
-
-/*
- * For backwards compatibility? This can be done in libc so Alpha
- * and all newer ports shouldn't need it.
- */
-SYSCALL_DEFINE1(alarm, unsigned int, seconds)
-{
- return alarm_setitimer(seconds);
-}
-
-#endif
-
-static void process_timeout(unsigned long __data)
-{
- wake_up_process((struct task_struct *)__data);
-}
-
-/**
- * schedule_timeout - sleep until timeout
- * @timeout: timeout value in jiffies
- *
- * Make the current task sleep until @timeout jiffies have
- * 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 jiffies are guaranteed to
- * pass before the routine returns. The routine will return 0
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task. In this case the remaining time
- * in jiffies will be returned, or 0 if the timer expired in time
- *
- * The current task state is guaranteed to be TASK_RUNNING when this
- * routine returns.
- *
- * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule
- * the CPU away without a bound on the timeout. In this case the return
- * value will be %MAX_SCHEDULE_TIMEOUT.
- *
- * In all cases the return value is guaranteed to be non-negative.
- */
-signed long __sched schedule_timeout(signed long timeout)
-{
- struct timer_list timer;
- unsigned long expire;
-
- switch (timeout)
- {
- case MAX_SCHEDULE_TIMEOUT:
- /*
- * These two special cases are useful to be comfortable
- * in the caller. Nothing more. We could take
- * MAX_SCHEDULE_TIMEOUT from one of the negative value
- * but I' d like to return a valid offset (>=0) to allow
- * the caller to do everything it want with the retval.
- */
- schedule();
- goto out;
- default:
- /*
- * Another bit of PARANOID. Note that the retval will be
- * 0 since no piece of kernel is supposed to do a check
- * for a negative retval of schedule_timeout() (since it
- * should never happens anyway). You just have the printk()
- * that will tell you if something is gone wrong and where.
- */
- if (timeout < 0) {
- printk(KERN_ERR "schedule_timeout: wrong timeout "
- "value %lx\n", timeout);
- dump_stack();
- current->state = TASK_RUNNING;
- goto out;
- }
- }
-
- expire = timeout + jiffies;
-
- setup_timer_on_stack(&timer, process_timeout, (unsigned long)current);
- __mod_timer(&timer, expire, false, TIMER_NOT_PINNED);
- schedule();
- del_singleshot_timer_sync(&timer);
-
- /* Remove the timer from the object tracker */
- destroy_timer_on_stack(&timer);
-
- timeout = expire - jiffies;
-
- out:
- return timeout < 0 ? 0 : timeout;
-}
-EXPORT_SYMBOL(schedule_timeout);
-
-/*
- * We can use __set_current_state() here because schedule_timeout() calls
- * schedule() unconditionally.
- */
-signed long __sched schedule_timeout_interruptible(signed long timeout)
-{
- __set_current_state(TASK_INTERRUPTIBLE);
- return schedule_timeout(timeout);
-}
-EXPORT_SYMBOL(schedule_timeout_interruptible);
-
-signed long __sched schedule_timeout_killable(signed long timeout)
-{
- __set_current_state(TASK_KILLABLE);
- return schedule_timeout(timeout);
-}
-EXPORT_SYMBOL(schedule_timeout_killable);
-
-signed long __sched schedule_timeout_uninterruptible(signed long timeout)
-{
- __set_current_state(TASK_UNINTERRUPTIBLE);
- return schedule_timeout(timeout);
-}
-EXPORT_SYMBOL(schedule_timeout_uninterruptible);
-
-static int init_timers_cpu(int cpu)
-{
- int j;
- struct tvec_base *base;
- static char tvec_base_done[NR_CPUS];
-
- if (!tvec_base_done[cpu]) {
- static char boot_done;
-
- if (boot_done) {
- /*
- * The APs use this path later in boot
- */
- base = kzalloc_node(sizeof(*base), GFP_KERNEL,
- cpu_to_node(cpu));
- if (!base)
- return -ENOMEM;
-
- /* Make sure tvec_base has TIMER_FLAG_MASK bits free */
- if (WARN_ON(base != tbase_get_base(base))) {
- kfree(base);
- return -ENOMEM;
- }
- per_cpu(tvec_bases, cpu) = base;
- } else {
- /*
- * This is for the boot CPU - we use compile-time
- * static initialisation because per-cpu memory isn't
- * ready yet and because the memory allocators are not
- * initialised either.
- */
- boot_done = 1;
- base = &boot_tvec_bases;
- }
- spin_lock_init(&base->lock);
- tvec_base_done[cpu] = 1;
- } else {
- base = per_cpu(tvec_bases, cpu);
- }
-
-
- for (j = 0; j < TVN_SIZE; j++) {
- INIT_LIST_HEAD(base->tv5.vec + j);
- INIT_LIST_HEAD(base->tv4.vec + j);
- INIT_LIST_HEAD(base->tv3.vec + j);
- INIT_LIST_HEAD(base->tv2.vec + j);
- }
- for (j = 0; j < TVR_SIZE; j++)
- INIT_LIST_HEAD(base->tv1.vec + j);
-
- base->timer_jiffies = jiffies;
- base->next_timer = base->timer_jiffies;
- base->active_timers = 0;
- base->all_timers = 0;
- return 0;
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-static void migrate_timer_list(struct tvec_base *new_base, struct list_head *head)
-{
- struct timer_list *timer;
-
- while (!list_empty(head)) {
- timer = list_first_entry(head, struct timer_list, entry);
- /* We ignore the accounting on the dying cpu */
- detach_timer(timer, false);
- timer_set_base(timer, new_base);
- internal_add_timer(new_base, timer);
- }
-}
-
-static void migrate_timers(int cpu)
-{
- struct tvec_base *old_base;
- struct tvec_base *new_base;
- int i;
-
- BUG_ON(cpu_online(cpu));
- old_base = per_cpu(tvec_bases, cpu);
- new_base = get_cpu_var(tvec_bases);
- /*
- * The caller is globally serialized and nobody else
- * takes two locks at once, deadlock is not possible.
- */
- spin_lock_irq(&new_base->lock);
- spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
-
- BUG_ON(old_base->running_timer);
-
- for (i = 0; i < TVR_SIZE; i++)
- migrate_timer_list(new_base, old_base->tv1.vec + i);
- for (i = 0; i < TVN_SIZE; i++) {
- migrate_timer_list(new_base, old_base->tv2.vec + i);
- migrate_timer_list(new_base, old_base->tv3.vec + i);
- migrate_timer_list(new_base, old_base->tv4.vec + i);
- migrate_timer_list(new_base, old_base->tv5.vec + i);
- }
-
- spin_unlock(&old_base->lock);
- spin_unlock_irq(&new_base->lock);
- put_cpu_var(tvec_bases);
-}
-#endif /* CONFIG_HOTPLUG_CPU */
-
-static int timer_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- long cpu = (long)hcpu;
- int err;
-
- switch(action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- err = init_timers_cpu(cpu);
- if (err < 0)
- return notifier_from_errno(err);
- break;
-#ifdef CONFIG_HOTPLUG_CPU
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- migrate_timers(cpu);
- break;
-#endif
- default:
- break;
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block timers_nb = {
- .notifier_call = timer_cpu_notify,
-};
-
-
-void __init init_timers(void)
-{
- int err;
-
- /* ensure there are enough low bits for flags in timer->base pointer */
- BUILD_BUG_ON(__alignof__(struct tvec_base) & TIMER_FLAG_MASK);
-
- err = timer_cpu_notify(&timers_nb, (unsigned long)CPU_UP_PREPARE,
- (void *)(long)smp_processor_id());
- BUG_ON(err != NOTIFY_OK);
-
- init_timer_stats();
- register_cpu_notifier(&timers_nb);
- open_softirq(TIMER_SOFTIRQ, run_timer_softirq);
-}
-
-/**
- * msleep - sleep safely even with waitqueue interruptions
- * @msecs: Time in milliseconds to sleep for
- */
-void msleep(unsigned int msecs)
-{
- unsigned long timeout = msecs_to_jiffies(msecs) + 1;
-
- while (timeout)
- timeout = schedule_timeout_uninterruptible(timeout);
-}
-
-EXPORT_SYMBOL(msleep);
-
-/**
- * msleep_interruptible - sleep waiting for signals
- * @msecs: Time in milliseconds to sleep for
- */
-unsigned long msleep_interruptible(unsigned int msecs)
-{
- unsigned long timeout = msecs_to_jiffies(msecs) + 1;
-
- while (timeout && !signal_pending(current))
- timeout = schedule_timeout_interruptible(timeout);
- return jiffies_to_msecs(timeout);
-}
-
-EXPORT_SYMBOL(msleep_interruptible);
-
-static int __sched do_usleep_range(unsigned long min, unsigned long max)
-{
- ktime_t kmin;
- unsigned long delta;
-
- kmin = ktime_set(0, min * NSEC_PER_USEC);
- delta = (max - min) * NSEC_PER_USEC;
- return schedule_hrtimeout_range(&kmin, delta, HRTIMER_MODE_REL);
-}
-
-/**
- * usleep_range - Drop in replacement for udelay where wakeup is flexible
- * @min: Minimum time in usecs to sleep
- * @max: Maximum time in usecs to sleep
- */
-void usleep_range(unsigned long min, unsigned long max)
-{
- __set_current_state(TASK_UNINTERRUPTIBLE);
- do_usleep_range(min, max);
-}
-EXPORT_SYMBOL(usleep_range);