diff options
Diffstat (limited to 'include/linux/hrtimer.h')
-rw-r--r-- | include/linux/hrtimer.h | 171 |
1 files changed, 33 insertions, 138 deletions
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 641c4567cfa7..f7bfdcf0dda3 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -18,12 +18,8 @@ #include <linux/list.h> #include <linux/percpu-defs.h> #include <linux/rbtree.h> -#include <linux/seqlock.h> #include <linux/timer.h> -struct hrtimer_clock_base; -struct hrtimer_cpu_base; - /* * Mode arguments of xxx_hrtimer functions: * @@ -98,107 +94,6 @@ struct hrtimer_sleeper { struct task_struct *task; }; -#ifdef CONFIG_64BIT -# define __hrtimer_clock_base_align ____cacheline_aligned -#else -# define __hrtimer_clock_base_align -#endif - -/** - * 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. - * @clockid: clock id for per_cpu support - * @seq: seqcount around __run_hrtimer - * @running: pointer to the currently running hrtimer - * @active: red black tree root node for the active timers - * @get_time: function to retrieve the current time of the clock - * @offset: offset of this clock to the monotonic base - */ -struct hrtimer_clock_base { - struct hrtimer_cpu_base *cpu_base; - unsigned int index; - clockid_t clockid; - seqcount_raw_spinlock_t seq; - struct hrtimer *running; - struct timerqueue_head active; - ktime_t (*get_time)(void); - ktime_t offset; -} __hrtimer_clock_base_align; - -enum hrtimer_base_type { - HRTIMER_BASE_MONOTONIC, - HRTIMER_BASE_REALTIME, - HRTIMER_BASE_BOOTTIME, - HRTIMER_BASE_TAI, - HRTIMER_BASE_MONOTONIC_SOFT, - HRTIMER_BASE_REALTIME_SOFT, - HRTIMER_BASE_BOOTTIME_SOFT, - HRTIMER_BASE_TAI_SOFT, - HRTIMER_MAX_CLOCK_BASES, -}; - -/** - * struct hrtimer_cpu_base - the per cpu clock bases - * @lock: lock protecting the base and associated clock bases - * and timers - * @cpu: cpu number - * @active_bases: Bitfield to mark bases with active timers - * @clock_was_set_seq: Sequence counter of clock was set events - * @hres_active: State of high resolution mode - * @in_hrtirq: hrtimer_interrupt() is currently executing - * @hang_detected: The last hrtimer interrupt detected a hang - * @softirq_activated: displays, if the softirq is raised - update of softirq - * related settings is not required then. - * @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 - * @softirq_expiry_lock: Lock which is taken while softirq based hrtimer are - * expired - * @online: CPU is online from an hrtimers point of view - * @timer_waiters: A hrtimer_cancel() invocation waits for the timer - * callback to finish. - * @expires_next: absolute time of the next event, is required for remote - * hrtimer enqueue; it is the total first expiry time (hard - * and soft hrtimer are taken into account) - * @next_timer: Pointer to the first expiring timer - * @softirq_expires_next: Time to check, if soft queues needs also to be expired - * @softirq_next_timer: Pointer to the first expiring softirq based timer - * @clock_base: array of clock bases for this cpu - * - * Note: next_timer is just an optimization for __remove_hrtimer(). - * Do not dereference the pointer because it is not reliable on - * cross cpu removals. - */ -struct hrtimer_cpu_base { - raw_spinlock_t lock; - unsigned int cpu; - unsigned int active_bases; - unsigned int clock_was_set_seq; - unsigned int hres_active : 1, - in_hrtirq : 1, - hang_detected : 1, - softirq_activated : 1, - online : 1; -#ifdef CONFIG_HIGH_RES_TIMERS - unsigned int nr_events; - unsigned short nr_retries; - unsigned short nr_hangs; - unsigned int max_hang_time; -#endif -#ifdef CONFIG_PREEMPT_RT - spinlock_t softirq_expiry_lock; - atomic_t timer_waiters; -#endif - ktime_t expires_next; - struct hrtimer *next_timer; - ktime_t softirq_expires_next; - struct hrtimer *softirq_next_timer; - struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES]; -} ____cacheline_aligned; - static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time) { timer->node.expires = time; @@ -333,32 +228,17 @@ static inline void hrtimer_cancel_wait_running(struct hrtimer *timer) /* Initialize timers: */ extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock, enum hrtimer_mode mode); -extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, clockid_t clock_id, - enum hrtimer_mode mode); +extern void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function)(struct hrtimer *), + clockid_t clock_id, enum hrtimer_mode mode); +extern void hrtimer_setup_on_stack(struct hrtimer *timer, + enum hrtimer_restart (*function)(struct hrtimer *), + clockid_t clock_id, enum hrtimer_mode mode); +extern void hrtimer_setup_sleeper_on_stack(struct hrtimer_sleeper *sl, clockid_t clock_id, + 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 hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl, - clockid_t clock_id, - 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 hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl, - clockid_t clock_id, - enum hrtimer_mode mode) -{ - hrtimer_init_sleeper(sl, clock_id, mode); -} - static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { } #endif @@ -442,25 +322,39 @@ static inline int hrtimer_callback_running(struct hrtimer *timer) return timer->base->running == timer; } +/** + * hrtimer_update_function - Update the timer's callback function + * @timer: Timer to update + * @function: New callback function + * + * Only safe to call if the timer is not enqueued. Can be called in the callback function if the + * timer is not enqueued at the same time (see the comments above HRTIMER_STATE_ENQUEUED). + */ +static inline void hrtimer_update_function(struct hrtimer *timer, + enum hrtimer_restart (*function)(struct hrtimer *)) +{ + guard(raw_spinlock_irqsave)(&timer->base->cpu_base->lock); + + if (WARN_ON_ONCE(hrtimer_is_queued(timer))) + return; + + if (WARN_ON_ONCE(!function)) + return; + + timer->function = function; +} + /* Forward a hrtimer so it expires after now: */ extern u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval); /** - * hrtimer_forward_now - forward the timer expiry so it expires after now + * hrtimer_forward_now() - forward the timer expiry so it expires after now * @timer: hrtimer to forward * @interval: the interval to forward * - * Forward the timer expiry so it will expire after the current time - * of the hrtimer clock base. Returns the number of overruns. - * - * Can be safely called from the callback function of @timer. If - * called from other contexts @timer must neither be enqueued nor - * running the callback and the caller needs to take care of - * serialization. - * - * Note: This only updates the timer expiry value and does not requeue - * the timer. + * It is a variant of hrtimer_forward(). The timer will expire after the current + * time of the hrtimer clock base. See hrtimer_forward() for details. */ static inline u64 hrtimer_forward_now(struct hrtimer *timer, ktime_t interval) @@ -492,6 +386,7 @@ extern void __init hrtimers_init(void); extern void sysrq_timer_list_show(void); int hrtimers_prepare_cpu(unsigned int cpu); +int hrtimers_cpu_starting(unsigned int cpu); #ifdef CONFIG_HOTPLUG_CPU int hrtimers_cpu_dying(unsigned int cpu); #else |