diff options
Diffstat (limited to 'include/linux/tick.h')
| -rw-r--r-- | include/linux/tick.h | 409 |
1 files changed, 270 insertions, 139 deletions
diff --git a/include/linux/tick.h b/include/linux/tick.h index 9180f4b85e6d..ac76ae9fa36d 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -1,7 +1,6 @@ -/* linux/include/linux/tick.h - * - * This file contains the structure definitions for tick related functions - * +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Tick related global functions */ #ifndef _LINUX_TICK_H #define _LINUX_TICK_H @@ -9,175 +8,307 @@ #include <linux/clockchips.h> #include <linux/irqflags.h> #include <linux/percpu.h> -#include <linux/hrtimer.h> +#include <linux/context_tracking_state.h> +#include <linux/cpumask.h> +#include <linux/sched.h> +#include <linux/rcupdate.h> +#include <linux/static_key.h> #ifdef CONFIG_GENERIC_CLOCKEVENTS +extern void __init tick_init(void); +/* Should be core only, but ARM BL switcher requires it */ +extern void tick_suspend_local(void); +/* Should be core only, but XEN resume magic and ARM BL switcher require it */ +extern void tick_resume_local(void); +#else /* CONFIG_GENERIC_CLOCKEVENTS */ +static inline void tick_init(void) { } +static inline void tick_suspend_local(void) { } +static inline void tick_resume_local(void) { } +#endif /* !CONFIG_GENERIC_CLOCKEVENTS */ -enum tick_device_mode { - TICKDEV_MODE_PERIODIC, - TICKDEV_MODE_ONESHOT, -}; +#if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_HOTPLUG_CPU) +extern int tick_cpu_dying(unsigned int cpu); +extern void tick_assert_timekeeping_handover(void); +#else +#define tick_cpu_dying NULL +static inline void tick_assert_timekeeping_handover(void) { } +#endif + +#if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND) +extern void tick_freeze(void); +extern void tick_unfreeze(void); +#else +static inline void tick_freeze(void) { } +static inline void tick_unfreeze(void) { } +#endif + +#ifdef CONFIG_TICK_ONESHOT +extern void tick_irq_enter(void); +# ifndef arch_needs_cpu +# define arch_needs_cpu() (0) +# endif +# else +static inline void tick_irq_enter(void) { } +#endif + +#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) +extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu); +#else +static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { } +#endif -struct tick_device { - struct clock_event_device *evtdev; - enum tick_device_mode mode; +enum tick_broadcast_mode { + TICK_BROADCAST_OFF, + TICK_BROADCAST_ON, + TICK_BROADCAST_FORCE, }; -enum tick_nohz_mode { - NOHZ_MODE_INACTIVE, - NOHZ_MODE_LOWRES, - NOHZ_MODE_HIGHRES, +enum tick_broadcast_state { + TICK_BROADCAST_EXIT, + TICK_BROADCAST_ENTER, }; -/** - * struct tick_sched - sched tick emulation and no idle tick control/stats - * @sched_timer: hrtimer to schedule the periodic tick in high - * resolution mode - * @last_tick: Store the last tick expiry time when the tick - * timer is modified for nohz sleeps. This is necessary - * to resume the tick timer operation in the timeline - * when the CPU returns from nohz sleep. - * @tick_stopped: Indicator that the idle tick has been stopped - * @idle_jiffies: jiffies at the entry to idle for idle time accounting - * @idle_calls: Total number of idle calls - * @idle_sleeps: Number of idle calls, where the sched tick was stopped - * @idle_entrytime: Time when the idle call was entered - * @idle_waketime: Time when the idle was interrupted - * @idle_exittime: Time when the idle state was left - * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped - * @iowait_sleeptime: Sum of the time slept in idle with sched tick stopped, with IO outstanding - * @sleep_length: Duration of the current idle sleep - * @do_timer_lst: CPU was the last one doing do_timer before going idle - */ -struct tick_sched { - struct hrtimer sched_timer; - unsigned long check_clocks; - enum tick_nohz_mode nohz_mode; - ktime_t last_tick; - int inidle; - int tick_stopped; - unsigned long idle_jiffies; - unsigned long idle_calls; - unsigned long idle_sleeps; - int idle_active; - ktime_t idle_entrytime; - ktime_t idle_waketime; - ktime_t idle_exittime; - ktime_t idle_sleeptime; - ktime_t iowait_sleeptime; - ktime_t sleep_length; - unsigned long last_jiffies; - unsigned long next_jiffies; - ktime_t idle_expires; - int do_timer_last; +extern struct static_key_false arch_needs_tick_broadcast; + +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST +extern void tick_broadcast_control(enum tick_broadcast_mode mode); +#else +static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { } +#endif /* BROADCAST */ + +#ifdef CONFIG_GENERIC_CLOCKEVENTS +extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state); +#else +static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state) +{ + return 0; +} +#endif + +static inline void tick_broadcast_enable(void) +{ + tick_broadcast_control(TICK_BROADCAST_ON); +} +static inline void tick_broadcast_disable(void) +{ + tick_broadcast_control(TICK_BROADCAST_OFF); +} +static inline void tick_broadcast_force(void) +{ + tick_broadcast_control(TICK_BROADCAST_FORCE); +} +static inline int tick_broadcast_enter(void) +{ + return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER); +} +static inline void tick_broadcast_exit(void) +{ + tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT); +} + +enum tick_dep_bits { + TICK_DEP_BIT_POSIX_TIMER = 0, + TICK_DEP_BIT_PERF_EVENTS = 1, + TICK_DEP_BIT_SCHED = 2, + TICK_DEP_BIT_CLOCK_UNSTABLE = 3, + TICK_DEP_BIT_RCU = 4, + TICK_DEP_BIT_RCU_EXP = 5 }; +#define TICK_DEP_BIT_MAX TICK_DEP_BIT_RCU_EXP -extern void __init tick_init(void); -extern int tick_is_oneshot_available(void); -extern struct tick_device *tick_get_device(int cpu); +#define TICK_DEP_MASK_NONE 0 +#define TICK_DEP_MASK_POSIX_TIMER (1 << TICK_DEP_BIT_POSIX_TIMER) +#define TICK_DEP_MASK_PERF_EVENTS (1 << TICK_DEP_BIT_PERF_EVENTS) +#define TICK_DEP_MASK_SCHED (1 << TICK_DEP_BIT_SCHED) +#define TICK_DEP_MASK_CLOCK_UNSTABLE (1 << TICK_DEP_BIT_CLOCK_UNSTABLE) +#define TICK_DEP_MASK_RCU (1 << TICK_DEP_BIT_RCU) +#define TICK_DEP_MASK_RCU_EXP (1 << TICK_DEP_BIT_RCU_EXP) -# ifdef CONFIG_HIGH_RES_TIMERS -extern int tick_init_highres(void); -extern int tick_program_event(ktime_t expires, int force); -extern void tick_setup_sched_timer(void); -# endif +#ifdef CONFIG_NO_HZ_COMMON +extern bool tick_nohz_enabled; +extern bool tick_nohz_tick_stopped(void); +extern bool tick_nohz_tick_stopped_cpu(int cpu); +extern void tick_nohz_idle_stop_tick(void); +extern void tick_nohz_idle_retain_tick(void); +extern void tick_nohz_idle_restart_tick(void); +extern void tick_nohz_idle_enter(void); +extern void tick_nohz_idle_exit(void); +extern void tick_nohz_irq_exit(void); +extern bool tick_nohz_idle_got_tick(void); +extern ktime_t tick_nohz_get_next_hrtimer(void); +extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next); +extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu); +extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); +extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); +#else /* !CONFIG_NO_HZ_COMMON */ +#define tick_nohz_enabled (0) +static inline int tick_nohz_tick_stopped(void) { return 0; } +static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; } +static inline void tick_nohz_idle_stop_tick(void) { } +static inline void tick_nohz_idle_retain_tick(void) { } +static inline void tick_nohz_idle_restart_tick(void) { } +static inline void tick_nohz_idle_enter(void) { } +static inline void tick_nohz_idle_exit(void) { } +static inline bool tick_nohz_idle_got_tick(void) { return false; } +static inline ktime_t tick_nohz_get_next_hrtimer(void) +{ + /* Next wake up is the tick period, assume it starts now */ + return ktime_add(ktime_get(), TICK_NSEC); +} +static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next) +{ + *delta_next = TICK_NSEC; + return *delta_next; +} +static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } +static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } +#endif /* !CONFIG_NO_HZ_COMMON */ -# if defined CONFIG_NO_HZ_COMMON || defined CONFIG_HIGH_RES_TIMERS -extern void tick_cancel_sched_timer(int cpu); -# else -static inline void tick_cancel_sched_timer(int cpu) { } -# endif +/* + * Mask of CPUs that are nohz_full. + * + * Users should be guarded by CONFIG_NO_HZ_FULL or a tick_nohz_full_cpu() + * check. + */ +extern cpumask_var_t tick_nohz_full_mask; -# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST -extern struct tick_device *tick_get_broadcast_device(void); -extern struct cpumask *tick_get_broadcast_mask(void); +#ifdef CONFIG_NO_HZ_FULL +extern bool tick_nohz_full_running; -# ifdef CONFIG_TICK_ONESHOT -extern struct cpumask *tick_get_broadcast_oneshot_mask(void); -# endif +static inline bool tick_nohz_full_enabled(void) +{ + if (!context_tracking_enabled()) + return false; -# endif /* BROADCAST */ + return tick_nohz_full_running; +} -# ifdef CONFIG_TICK_ONESHOT -extern void tick_clock_notify(void); -extern int tick_check_oneshot_change(int allow_nohz); -extern struct tick_sched *tick_get_tick_sched(int cpu); -extern void tick_check_idle(int cpu); -extern int tick_oneshot_mode_active(void); -# ifndef arch_needs_cpu -# define arch_needs_cpu(cpu) (0) -# endif -# else -static inline void tick_clock_notify(void) { } -static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } -static inline void tick_check_idle(int cpu) { } -static inline int tick_oneshot_mode_active(void) { return 0; } -# endif +/* + * Check if a CPU is part of the nohz_full subset. Arrange for evaluating + * the cpu expression (typically smp_processor_id()) _after_ the static + * key. + */ +#define tick_nohz_full_cpu(_cpu) ({ \ + bool __ret = false; \ + if (tick_nohz_full_enabled()) \ + __ret = cpumask_test_cpu((_cpu), tick_nohz_full_mask); \ + __ret; \ +}) -#else /* CONFIG_GENERIC_CLOCKEVENTS */ -static inline void tick_init(void) { } -static inline void tick_cancel_sched_timer(int cpu) { } -static inline void tick_clock_notify(void) { } -static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } -static inline void tick_check_idle(int cpu) { } -static inline int tick_oneshot_mode_active(void) { return 0; } -#endif /* !CONFIG_GENERIC_CLOCKEVENTS */ +extern void tick_nohz_dep_set(enum tick_dep_bits bit); +extern void tick_nohz_dep_clear(enum tick_dep_bits bit); +extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit); +extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit); +extern void tick_nohz_dep_set_task(struct task_struct *tsk, + enum tick_dep_bits bit); +extern void tick_nohz_dep_clear_task(struct task_struct *tsk, + enum tick_dep_bits bit); +extern void tick_nohz_dep_set_signal(struct task_struct *tsk, + enum tick_dep_bits bit); +extern void tick_nohz_dep_clear_signal(struct signal_struct *signal, + enum tick_dep_bits bit); +extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu); -# ifdef CONFIG_NO_HZ_COMMON -DECLARE_PER_CPU(struct tick_sched, tick_cpu_sched); +/* + * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases + * on top of static keys. + */ +static inline void tick_dep_set(enum tick_dep_bits bit) +{ + if (tick_nohz_full_enabled()) + tick_nohz_dep_set(bit); +} -static inline int tick_nohz_tick_stopped(void) +static inline void tick_dep_clear(enum tick_dep_bits bit) { - return __this_cpu_read(tick_cpu_sched.tick_stopped); + if (tick_nohz_full_enabled()) + tick_nohz_dep_clear(bit); } -extern void tick_nohz_idle_enter(void); -extern void tick_nohz_idle_exit(void); -extern void tick_nohz_irq_exit(void); -extern ktime_t tick_nohz_get_sleep_length(void); -extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); -extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); +static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) +{ + if (tick_nohz_full_cpu(cpu)) + tick_nohz_dep_set_cpu(cpu, bit); +} -# else /* !CONFIG_NO_HZ_COMMON */ -static inline int tick_nohz_tick_stopped(void) +static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { - return 0; + if (tick_nohz_full_cpu(cpu)) + tick_nohz_dep_clear_cpu(cpu, bit); } -static inline void tick_nohz_idle_enter(void) { } -static inline void tick_nohz_idle_exit(void) { } +static inline void tick_dep_set_task(struct task_struct *tsk, + enum tick_dep_bits bit) +{ + if (tick_nohz_full_enabled()) + tick_nohz_dep_set_task(tsk, bit); +} -static inline ktime_t tick_nohz_get_sleep_length(void) +static inline void tick_dep_clear_task(struct task_struct *tsk, + enum tick_dep_bits bit) { - ktime_t len = { .tv64 = NSEC_PER_SEC/HZ }; + if (tick_nohz_full_enabled()) + tick_nohz_dep_clear_task(tsk, bit); +} - return len; +static inline void tick_dep_init_task(struct task_struct *tsk) +{ + atomic_set(&tsk->tick_dep_mask, 0); } -static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } -static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } -# endif /* !CONFIG_NO_HZ_COMMON */ -#ifdef CONFIG_NO_HZ_FULL -extern void tick_nohz_init(void); -extern int tick_nohz_full_cpu(int cpu); -extern void tick_nohz_full_check(void); -extern void tick_nohz_full_kick(void); -extern void tick_nohz_full_kick_all(void); -extern void tick_nohz_task_switch(struct task_struct *tsk); +static inline void tick_dep_set_signal(struct task_struct *tsk, + enum tick_dep_bits bit) +{ + if (tick_nohz_full_enabled()) + tick_nohz_dep_set_signal(tsk, bit); +} +static inline void tick_dep_clear_signal(struct signal_struct *signal, + enum tick_dep_bits bit) +{ + if (tick_nohz_full_enabled()) + tick_nohz_dep_clear_signal(signal, bit); +} + +extern void tick_nohz_full_kick_cpu(int cpu); +extern void __tick_nohz_task_switch(void); +extern void __init tick_nohz_full_setup(cpumask_var_t cpumask); #else -static inline void tick_nohz_init(void) { } -static inline int tick_nohz_full_cpu(int cpu) { return 0; } -static inline void tick_nohz_full_check(void) { } -static inline void tick_nohz_full_kick(void) { } -static inline void tick_nohz_full_kick_all(void) { } -static inline void tick_nohz_task_switch(struct task_struct *tsk) { } +static inline bool tick_nohz_full_enabled(void) { return false; } +static inline bool tick_nohz_full_cpu(int cpu) { return false; } + +static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } +static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } +static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; } + +static inline void tick_dep_set(enum tick_dep_bits bit) { } +static inline void tick_dep_clear(enum tick_dep_bits bit) { } +static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } +static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } +static inline void tick_dep_set_task(struct task_struct *tsk, + enum tick_dep_bits bit) { } +static inline void tick_dep_clear_task(struct task_struct *tsk, + enum tick_dep_bits bit) { } +static inline void tick_dep_init_task(struct task_struct *tsk) { } +static inline void tick_dep_set_signal(struct task_struct *tsk, + enum tick_dep_bits bit) { } +static inline void tick_dep_clear_signal(struct signal_struct *signal, + enum tick_dep_bits bit) { } + +static inline void tick_nohz_full_kick_cpu(int cpu) { } +static inline void __tick_nohz_task_switch(void) { } +static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { } #endif +static inline void tick_nohz_task_switch(void) +{ + if (tick_nohz_full_enabled()) + __tick_nohz_task_switch(); +} -# ifdef CONFIG_CPU_IDLE_GOV_MENU -extern void menu_hrtimer_cancel(void); -# else -static inline void menu_hrtimer_cancel(void) {} -# endif /* CONFIG_CPU_IDLE_GOV_MENU */ +static inline void tick_nohz_user_enter_prepare(void) +{ + if (tick_nohz_full_cpu(smp_processor_id())) + rcu_nocb_flush_deferred_wakeup(); +} #endif |