#include <linux/init.h>
#include <linux/list.h>
#include <linux/wait.h>
+#include <linux/percpu.h>
+#include <linux/timer.h>
+
+
+struct hrtimer_clock_base;
+struct hrtimer_cpu_base;
/*
* Mode arguments of xxx_hrtimer functions:
*/
enum hrtimer_mode {
- HRTIMER_ABS, /* Time value is absolute */
- HRTIMER_REL, /* Time value is relative to now */
+ HRTIMER_MODE_ABS = 0x0, /* Time value is absolute */
+ HRTIMER_MODE_REL = 0x1, /* Time value is relative to now */
+ HRTIMER_MODE_PINNED = 0x02, /* Timer is bound to CPU */
+ HRTIMER_MODE_ABS_PINNED = 0x02,
+ HRTIMER_MODE_REL_PINNED = 0x03,
};
+/*
+ * Return values for the callback function
+ */
enum hrtimer_restart {
- HRTIMER_NORESTART,
- HRTIMER_RESTART,
+ HRTIMER_NORESTART, /* Timer is not restarted */
+ HRTIMER_RESTART, /* Timer must be restarted */
};
-#define HRTIMER_INACTIVE ((void *)1UL)
-
-struct hrtimer_base;
+/*
+ * Values to track state of the timer
+ *
+ * Possible states:
+ *
+ * 0x00 inactive
+ * 0x01 enqueued into rbtree
+ * 0x02 callback function running
+ *
+ * Special cases:
+ * 0x03 callback function running and enqueued
+ * (was requeued on another CPU)
+ * 0x09 timer was migrated on CPU hotunplug
+ * The "callback function running and enqueued" status is only possible on
+ * SMP. It happens for example when a posix timer expired and the callback
+ * queued a signal. Between dropping the lock which protects the posix timer
+ * and reacquiring the base lock of the hrtimer, another CPU can deliver the
+ * signal and rearm the timer. We have to preserve the callback running state,
+ * as otherwise the timer could be removed before the softirq code finishes the
+ * the handling of the timer.
+ *
+ * The HRTIMER_STATE_ENQUEUED bit is always or'ed to the current state to
+ * preserve the HRTIMER_STATE_CALLBACK bit in the above scenario.
+ *
+ * All state transitions are protected by cpu_base->lock.
+ */
+#define HRTIMER_STATE_INACTIVE 0x00
+#define HRTIMER_STATE_ENQUEUED 0x01
+#define HRTIMER_STATE_CALLBACK 0x02
+#define HRTIMER_STATE_MIGRATE 0x04
/**
* struct hrtimer - the basic hrtimer structure
- *
* @node: red black tree node for time ordered insertion
- * @expires: the absolute expiry time in the hrtimers internal
+ * @_expires: the absolute expiry time in the hrtimers internal
* representation. The time is related to the clock on
- * which the timer is based.
+ * which the timer is based. Is setup by adding
+ * slack to the _softexpires value. For non range timers
+ * identical to _softexpires.
+ * @_softexpires: the absolute earliest expiry time of the hrtimer.
+ * The time which was given as expiry time when the timer
+ * was armed.
* @function: timer expiry callback function
* @base: pointer to the timer base (per cpu and per clock)
+ * @state: state information (See bit values above)
+ * @start_site: timer statistics field to store the site where the timer
+ * was started
+ * @start_comm: timer statistics field to store the name of the process which
+ * started the timer
+ * @start_pid: timer statistics field to store the pid of the task which
+ * started the timer
*
- * The hrtimer structure must be initialized by init_hrtimer_#CLOCKTYPE()
+ * The hrtimer structure must be initialized by hrtimer_init()
*/
struct hrtimer {
- struct rb_node node;
- ktime_t expires;
- int (*function)(struct hrtimer *);
- struct hrtimer_base *base;
+ struct rb_node node;
+ ktime_t _expires;
+ ktime_t _softexpires;
+ enum hrtimer_restart (*function)(struct hrtimer *);
+ struct hrtimer_clock_base *base;
+ unsigned long state;
+#ifdef CONFIG_TIMER_STATS
+ int start_pid;
+ void *start_site;
+ char start_comm[16];
+#endif
};
/**
* struct hrtimer_sleeper - simple sleeper structure
- *
* @timer: embedded timer structure
* @task: task to wake up
*
};
/**
- * struct hrtimer_base - the timer base for a specific clock
- *
- * @index: clock type index for per_cpu support when moving a timer
- * to a base on another cpu.
- * @lock: lock protecting the base and associated timers
+ * struct hrtimer_clock_base - the timer base for a specific clock
+ * @cpu_base: per cpu clock base
+ * @index: clock type index for per_cpu support when moving a
+ * timer to a base on another cpu.
* @active: red black tree root node for the active timers
* @first: pointer to the timer node which expires first
* @resolution: the resolution of the clock, in nanoseconds
* @get_time: function to retrieve the current time of the clock
- * @get_sofirq_time: function to retrieve the current time from the softirq
- * @curr_timer: the timer which is executing a callback right now
* @softirq_time: the time when running the hrtimer queue in the softirq
+ * @offset: offset of this clock to the monotonic base
*/
-struct hrtimer_base {
+struct hrtimer_clock_base {
+ struct hrtimer_cpu_base *cpu_base;
clockid_t index;
- spinlock_t lock;
struct rb_root active;
struct rb_node *first;
ktime_t resolution;
ktime_t (*get_time)(void);
- ktime_t (*get_softirq_time)(void);
- struct hrtimer *curr_timer;
ktime_t softirq_time;
+#ifdef CONFIG_HIGH_RES_TIMERS
+ ktime_t offset;
+#endif
};
+#define HRTIMER_MAX_CLOCK_BASES 2
+
+/*
+ * struct hrtimer_cpu_base - the per cpu clock bases
+ * @lock: lock protecting the base and associated clock bases
+ * and timers
+ * @clock_base: array of clock bases for this cpu
+ * @curr_timer: the timer which is executing a callback right now
+ * @expires_next: absolute time of the next event which was scheduled
+ * via clock_set_next_event()
+ * @hres_active: State of high resolution mode
+ * @hang_detected: The last hrtimer interrupt detected a hang
+ * @nr_events: Total number of hrtimer interrupt events
+ * @nr_retries: Total number of hrtimer interrupt retries
+ * @nr_hangs: Total number of hrtimer interrupt hangs
+ * @max_hang_time: Maximum time spent in hrtimer_interrupt
+ */
+struct hrtimer_cpu_base {
+ spinlock_t lock;
+ struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES];
+#ifdef CONFIG_HIGH_RES_TIMERS
+ ktime_t expires_next;
+ int hres_active;
+ int hang_detected;
+ unsigned long nr_events;
+ unsigned long nr_retries;
+ unsigned long nr_hangs;
+ ktime_t max_hang_time;
+#endif
+};
+
+static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time)
+{
+ timer->_expires = time;
+ timer->_softexpires = time;
+}
+
+static inline void hrtimer_set_expires_range(struct hrtimer *timer, ktime_t time, ktime_t delta)
+{
+ timer->_softexpires = time;
+ timer->_expires = ktime_add_safe(time, delta);
+}
+
+static inline void hrtimer_set_expires_range_ns(struct hrtimer *timer, ktime_t time, unsigned long delta)
+{
+ timer->_softexpires = time;
+ timer->_expires = ktime_add_safe(time, ns_to_ktime(delta));
+}
+
+static inline void hrtimer_set_expires_tv64(struct hrtimer *timer, s64 tv64)
+{
+ timer->_expires.tv64 = tv64;
+ timer->_softexpires.tv64 = tv64;
+}
+
+static inline void hrtimer_add_expires(struct hrtimer *timer, ktime_t time)
+{
+ timer->_expires = ktime_add_safe(timer->_expires, time);
+ timer->_softexpires = ktime_add_safe(timer->_softexpires, time);
+}
+
+static inline void hrtimer_add_expires_ns(struct hrtimer *timer, u64 ns)
+{
+ timer->_expires = ktime_add_ns(timer->_expires, ns);
+ timer->_softexpires = ktime_add_ns(timer->_softexpires, ns);
+}
+
+static inline ktime_t hrtimer_get_expires(const struct hrtimer *timer)
+{
+ return timer->_expires;
+}
+
+static inline ktime_t hrtimer_get_softexpires(const struct hrtimer *timer)
+{
+ return timer->_softexpires;
+}
+
+static inline s64 hrtimer_get_expires_tv64(const struct hrtimer *timer)
+{
+ return timer->_expires.tv64;
+}
+static inline s64 hrtimer_get_softexpires_tv64(const struct hrtimer *timer)
+{
+ return timer->_softexpires.tv64;
+}
+
+static inline s64 hrtimer_get_expires_ns(const struct hrtimer *timer)
+{
+ return ktime_to_ns(timer->_expires);
+}
+
+static inline ktime_t hrtimer_expires_remaining(const struct hrtimer *timer)
+{
+ return ktime_sub(timer->_expires, timer->base->get_time());
+}
+
+#ifdef CONFIG_HIGH_RES_TIMERS
+struct clock_event_device;
+
+extern void clock_was_set(void);
+extern void hres_timers_resume(void);
+extern void hrtimer_interrupt(struct clock_event_device *dev);
+
+/*
+ * In high resolution mode the time reference must be read accurate
+ */
+static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer)
+{
+ return timer->base->get_time();
+}
+
+static inline int hrtimer_is_hres_active(struct hrtimer *timer)
+{
+ return timer->base->cpu_base->hres_active;
+}
+
+extern void hrtimer_peek_ahead_timers(void);
+
+/*
+ * The resolution of the clocks. The resolution value is returned in
+ * the clock_getres() system call to give application programmers an
+ * idea of the (in)accuracy of timers. Timer values are rounded up to
+ * this resolution values.
+ */
+# define HIGH_RES_NSEC 1
+# define KTIME_HIGH_RES (ktime_t) { .tv64 = HIGH_RES_NSEC }
+# define MONOTONIC_RES_NSEC HIGH_RES_NSEC
+# define KTIME_MONOTONIC_RES KTIME_HIGH_RES
+
+#else
+
+# define MONOTONIC_RES_NSEC LOW_RES_NSEC
+# define KTIME_MONOTONIC_RES KTIME_LOW_RES
+
/*
* clock_was_set() is a NOP for non- high-resolution systems. The
* time-sorted order guarantees that a timer does not expire early and
* is expired in the next softirq when the clock was advanced.
*/
-#define clock_was_set() do { } while (0)
+static inline void clock_was_set(void) { }
+static inline void hrtimer_peek_ahead_timers(void) { }
+
+static inline void hres_timers_resume(void) { }
+
+/*
+ * In non high resolution mode the time reference is taken from
+ * the base softirq time variable.
+ */
+static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer)
+{
+ return timer->base->softirq_time;
+}
+
+static inline int hrtimer_is_hres_active(struct hrtimer *timer)
+{
+ return 0;
+}
+#endif
+
+extern ktime_t ktime_get(void);
+extern ktime_t ktime_get_real(void);
+
+
+DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
+
/* Exported timer functions: */
extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
enum hrtimer_mode mode);
+#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
+extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
+ enum hrtimer_mode mode);
+
+extern void destroy_hrtimer_on_stack(struct hrtimer *timer);
+#else
+static inline void hrtimer_init_on_stack(struct hrtimer *timer,
+ clockid_t which_clock,
+ enum hrtimer_mode mode)
+{
+ hrtimer_init(timer, which_clock, mode);
+}
+static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { }
+#endif
+
/* Basic timer operations: */
extern int hrtimer_start(struct hrtimer *timer, ktime_t tim,
const enum hrtimer_mode mode);
+extern int hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
+ unsigned long range_ns, const enum hrtimer_mode mode);
+extern int
+__hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
+ unsigned long delta_ns,
+ const enum hrtimer_mode mode, int wakeup);
+
extern int hrtimer_cancel(struct hrtimer *timer);
extern int hrtimer_try_to_cancel(struct hrtimer *timer);
-#define hrtimer_restart(timer) hrtimer_start((timer), (timer)->expires, HRTIMER_ABS)
+static inline int hrtimer_start_expires(struct hrtimer *timer,
+ enum hrtimer_mode mode)
+{
+ unsigned long delta;
+ ktime_t soft, hard;
+ soft = hrtimer_get_softexpires(timer);
+ hard = hrtimer_get_expires(timer);
+ delta = ktime_to_ns(ktime_sub(hard, soft));
+ return hrtimer_start_range_ns(timer, soft, delta, mode);
+}
+
+static inline int hrtimer_restart(struct hrtimer *timer)
+{
+ return hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
+}
/* Query timers: */
extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer);
extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp);
-#ifdef CONFIG_NO_IDLE_HZ
extern ktime_t hrtimer_get_next_event(void);
-#endif
+/*
+ * A timer is active, when it is enqueued into the rbtree or the callback
+ * function is running.
+ */
static inline int hrtimer_active(const struct hrtimer *timer)
{
- return timer->node.rb_parent != HRTIMER_INACTIVE;
+ return timer->state != HRTIMER_STATE_INACTIVE;
+}
+
+/*
+ * Helper function to check, whether the timer is on one of the queues
+ */
+static inline int hrtimer_is_queued(struct hrtimer *timer)
+{
+ return timer->state & HRTIMER_STATE_ENQUEUED;
+}
+
+/*
+ * Helper function to check, whether the timer is running the callback
+ * function
+ */
+static inline int hrtimer_callback_running(struct hrtimer *timer)
+{
+ return timer->state & HRTIMER_STATE_CALLBACK;
}
/* Forward a hrtimer so it expires after now: */
-extern unsigned long
+extern u64
hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval);
+/* Forward a hrtimer so it expires after the hrtimer's current now */
+static inline u64 hrtimer_forward_now(struct hrtimer *timer,
+ ktime_t interval)
+{
+ return hrtimer_forward(timer, timer->base->get_time(), interval);
+}
+
/* Precise sleep: */
extern long hrtimer_nanosleep(struct timespec *rqtp,
struct timespec __user *rmtp,
const enum hrtimer_mode mode,
const clockid_t clockid);
+extern long hrtimer_nanosleep_restart(struct restart_block *restart_block);
extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
struct task_struct *tsk);
+extern int schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
+ const enum hrtimer_mode mode);
+extern int schedule_hrtimeout(ktime_t *expires, const enum hrtimer_mode mode);
+
/* Soft interrupt function to run the hrtimer queues: */
extern void hrtimer_run_queues(void);
+extern void hrtimer_run_pending(void);
/* Bootup initialization: */
extern void __init hrtimers_init(void);
+#if BITS_PER_LONG < 64
+extern u64 ktime_divns(const ktime_t kt, s64 div);
+#else /* BITS_PER_LONG < 64 */
+# define ktime_divns(kt, div) (u64)((kt).tv64 / (div))
+#endif
+
+/* Show pending timers: */
+extern void sysrq_timer_list_show(void);
+
#endif
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