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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * tick internal variable and functions used by low/high res code
4 */
5#include <linux/hrtimer.h>
6#include <linux/tick.h>
7
8#include "timekeeping.h"
9#include "tick-sched.h"
10
11#ifdef CONFIG_GENERIC_CLOCKEVENTS
12
13# define TICK_DO_TIMER_NONE -1
14# define TICK_DO_TIMER_BOOT -2
15
16DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
17extern ktime_t tick_next_period;
18extern int tick_do_timer_cpu __read_mostly;
19
20extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
21extern void tick_handle_periodic(struct clock_event_device *dev);
22extern void tick_check_new_device(struct clock_event_device *dev);
23extern void tick_shutdown(unsigned int cpu);
24extern void tick_suspend(void);
25extern void tick_resume(void);
26extern bool tick_check_replacement(struct clock_event_device *curdev,
27 struct clock_event_device *newdev);
28extern void tick_install_replacement(struct clock_event_device *dev);
29extern int tick_is_oneshot_available(void);
30extern struct tick_device *tick_get_device(int cpu);
31
32extern int clockevents_tick_resume(struct clock_event_device *dev);
33/* Check, if the device is functional or a dummy for broadcast */
34static inline int tick_device_is_functional(struct clock_event_device *dev)
35{
36 return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
37}
38
39static inline enum clock_event_state clockevent_get_state(struct clock_event_device *dev)
40{
41 return dev->state_use_accessors;
42}
43
44static inline void clockevent_set_state(struct clock_event_device *dev,
45 enum clock_event_state state)
46{
47 dev->state_use_accessors = state;
48}
49
50extern void clockevents_shutdown(struct clock_event_device *dev);
51extern void clockevents_exchange_device(struct clock_event_device *old,
52 struct clock_event_device *new);
53extern void clockevents_switch_state(struct clock_event_device *dev,
54 enum clock_event_state state);
55extern int clockevents_program_event(struct clock_event_device *dev,
56 ktime_t expires, bool force);
57extern void clockevents_handle_noop(struct clock_event_device *dev);
58extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
59extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
60
61/* Broadcasting support */
62# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
63extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
64extern void tick_install_broadcast_device(struct clock_event_device *dev, int cpu);
65extern int tick_is_broadcast_device(struct clock_event_device *dev);
66extern void tick_suspend_broadcast(void);
67extern void tick_resume_broadcast(void);
68extern bool tick_resume_check_broadcast(void);
69extern void tick_broadcast_init(void);
70extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
71extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
72extern struct tick_device *tick_get_broadcast_device(void);
73extern struct cpumask *tick_get_broadcast_mask(void);
74extern const struct clock_event_device *tick_get_wakeup_device(int cpu);
75# else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
76static inline void tick_install_broadcast_device(struct clock_event_device *dev, int cpu) { }
77static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
78static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
79static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
80static inline void tick_suspend_broadcast(void) { }
81static inline void tick_resume_broadcast(void) { }
82static inline bool tick_resume_check_broadcast(void) { return false; }
83static inline void tick_broadcast_init(void) { }
84static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }
85
86/* Set the periodic handler in non broadcast mode */
87static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
88{
89 dev->event_handler = tick_handle_periodic;
90}
91# endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
92
93#else /* !GENERIC_CLOCKEVENTS: */
94static inline void tick_suspend(void) { }
95static inline void tick_resume(void) { }
96#endif /* !GENERIC_CLOCKEVENTS */
97
98/* Oneshot related functions */
99#ifdef CONFIG_TICK_ONESHOT
100extern void tick_setup_oneshot(struct clock_event_device *newdev,
101 void (*handler)(struct clock_event_device *),
102 ktime_t nextevt);
103extern int tick_program_event(ktime_t expires, int force);
104extern void tick_oneshot_notify(void);
105extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
106extern void tick_resume_oneshot(void);
107static inline bool tick_oneshot_possible(void) { return true; }
108extern int tick_oneshot_mode_active(void);
109extern void tick_clock_notify(void);
110extern int tick_check_oneshot_change(int allow_nohz);
111extern int tick_init_highres(void);
112#else /* !CONFIG_TICK_ONESHOT: */
113static inline
114void tick_setup_oneshot(struct clock_event_device *newdev,
115 void (*handler)(struct clock_event_device *),
116 ktime_t nextevt) { BUG(); }
117static inline void tick_resume_oneshot(void) { BUG(); }
118static inline int tick_program_event(ktime_t expires, int force) { return 0; }
119static inline void tick_oneshot_notify(void) { }
120static inline bool tick_oneshot_possible(void) { return false; }
121static inline int tick_oneshot_mode_active(void) { return 0; }
122static inline void tick_clock_notify(void) { }
123static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
124#endif /* !CONFIG_TICK_ONESHOT */
125
126/* Functions related to oneshot broadcasting */
127#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
128extern void tick_broadcast_switch_to_oneshot(void);
129extern int tick_broadcast_oneshot_active(void);
130extern void tick_check_oneshot_broadcast_this_cpu(void);
131bool tick_broadcast_oneshot_available(void);
132extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
133#else /* !(BROADCAST && ONESHOT): */
134static inline void tick_broadcast_switch_to_oneshot(void) { }
135static inline int tick_broadcast_oneshot_active(void) { return 0; }
136static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
137static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
138#endif /* !(BROADCAST && ONESHOT) */
139
140#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
141extern void tick_broadcast_offline(unsigned int cpu);
142#else
143static inline void tick_broadcast_offline(unsigned int cpu) { }
144#endif
145
146/* NO_HZ_FULL internal */
147#ifdef CONFIG_NO_HZ_FULL
148extern void tick_nohz_init(void);
149# else
150static inline void tick_nohz_init(void) { }
151#endif
152
153#ifdef CONFIG_NO_HZ_COMMON
154extern unsigned long tick_nohz_active;
155extern void timers_update_nohz(void);
156# ifdef CONFIG_SMP
157extern struct static_key_false timers_migration_enabled;
158# endif
159#else /* CONFIG_NO_HZ_COMMON */
160static inline void timers_update_nohz(void) { }
161#define tick_nohz_active (0)
162#endif
163
164DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
165
166extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem);
167void timer_clear_idle(void);
168
169#define CLOCK_SET_WALL \
170 (BIT(HRTIMER_BASE_REALTIME) | BIT(HRTIMER_BASE_REALTIME_SOFT) | \
171 BIT(HRTIMER_BASE_TAI) | BIT(HRTIMER_BASE_TAI_SOFT))
172
173#define CLOCK_SET_BOOT \
174 (BIT(HRTIMER_BASE_BOOTTIME) | BIT(HRTIMER_BASE_BOOTTIME_SOFT))
175
176void clock_was_set(unsigned int bases);
177void clock_was_set_delayed(void);
178
179void hrtimers_resume_local(void);
180
181/* Since jiffies uses a simple TICK_NSEC multiplier
182 * conversion, the .shift value could be zero. However
183 * this would make NTP adjustments impossible as they are
184 * in units of 1/2^.shift. Thus we use JIFFIES_SHIFT to
185 * shift both the nominator and denominator the same
186 * amount, and give ntp adjustments in units of 1/2^8
187 *
188 * The value 8 is somewhat carefully chosen, as anything
189 * larger can result in overflows. TICK_NSEC grows as HZ
190 * shrinks, so values greater than 8 overflow 32bits when
191 * HZ=100.
192 */
193#if HZ < 34
194#define JIFFIES_SHIFT 6
195#elif HZ < 67
196#define JIFFIES_SHIFT 7
197#else
198#define JIFFIES_SHIFT 8
199#endif
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * tick internal variable and functions used by low/high res code
4 */
5#include <linux/hrtimer.h>
6#include <linux/tick.h>
7
8#include "timekeeping.h"
9#include "tick-sched.h"
10
11struct timer_events {
12 u64 local;
13 u64 global;
14};
15
16#ifdef CONFIG_GENERIC_CLOCKEVENTS
17
18# define TICK_DO_TIMER_NONE -1
19# define TICK_DO_TIMER_BOOT -2
20
21DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
22extern ktime_t tick_next_period;
23extern int tick_do_timer_cpu __read_mostly;
24
25extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
26extern void tick_handle_periodic(struct clock_event_device *dev);
27extern void tick_check_new_device(struct clock_event_device *dev);
28extern void tick_shutdown(unsigned int cpu);
29extern void tick_suspend(void);
30extern void tick_resume(void);
31extern bool tick_check_replacement(struct clock_event_device *curdev,
32 struct clock_event_device *newdev);
33extern void tick_install_replacement(struct clock_event_device *dev);
34extern int tick_is_oneshot_available(void);
35extern struct tick_device *tick_get_device(int cpu);
36
37extern int clockevents_tick_resume(struct clock_event_device *dev);
38/* Check, if the device is functional or a dummy for broadcast */
39static inline int tick_device_is_functional(struct clock_event_device *dev)
40{
41 return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
42}
43
44static inline enum clock_event_state clockevent_get_state(struct clock_event_device *dev)
45{
46 return dev->state_use_accessors;
47}
48
49static inline void clockevent_set_state(struct clock_event_device *dev,
50 enum clock_event_state state)
51{
52 dev->state_use_accessors = state;
53}
54
55extern void clockevents_shutdown(struct clock_event_device *dev);
56extern void clockevents_exchange_device(struct clock_event_device *old,
57 struct clock_event_device *new);
58extern void clockevents_switch_state(struct clock_event_device *dev,
59 enum clock_event_state state);
60extern int clockevents_program_event(struct clock_event_device *dev,
61 ktime_t expires, bool force);
62extern void clockevents_handle_noop(struct clock_event_device *dev);
63extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
64
65/* Broadcasting support */
66# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
67extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
68extern void tick_install_broadcast_device(struct clock_event_device *dev, int cpu);
69extern int tick_is_broadcast_device(struct clock_event_device *dev);
70extern void tick_suspend_broadcast(void);
71extern void tick_resume_broadcast(void);
72extern bool tick_resume_check_broadcast(void);
73extern void tick_broadcast_init(void);
74extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
75extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
76extern struct tick_device *tick_get_broadcast_device(void);
77extern struct cpumask *tick_get_broadcast_mask(void);
78extern const struct clock_event_device *tick_get_wakeup_device(int cpu);
79# else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
80static inline void tick_install_broadcast_device(struct clock_event_device *dev, int cpu) { }
81static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
82static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
83static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
84static inline void tick_suspend_broadcast(void) { }
85static inline void tick_resume_broadcast(void) { }
86static inline bool tick_resume_check_broadcast(void) { return false; }
87static inline void tick_broadcast_init(void) { }
88static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }
89
90/* Set the periodic handler in non broadcast mode */
91static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
92{
93 dev->event_handler = tick_handle_periodic;
94}
95# endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
96
97#else /* !GENERIC_CLOCKEVENTS: */
98static inline void tick_suspend(void) { }
99static inline void tick_resume(void) { }
100#endif /* !GENERIC_CLOCKEVENTS */
101
102/* Oneshot related functions */
103#ifdef CONFIG_TICK_ONESHOT
104extern void tick_setup_oneshot(struct clock_event_device *newdev,
105 void (*handler)(struct clock_event_device *),
106 ktime_t nextevt);
107extern int tick_program_event(ktime_t expires, int force);
108extern void tick_oneshot_notify(void);
109extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
110extern void tick_resume_oneshot(void);
111static inline bool tick_oneshot_possible(void) { return true; }
112extern int tick_oneshot_mode_active(void);
113extern void tick_clock_notify(void);
114extern int tick_check_oneshot_change(int allow_nohz);
115extern int tick_init_highres(void);
116#else /* !CONFIG_TICK_ONESHOT: */
117static inline
118void tick_setup_oneshot(struct clock_event_device *newdev,
119 void (*handler)(struct clock_event_device *),
120 ktime_t nextevt) { BUG(); }
121static inline void tick_resume_oneshot(void) { BUG(); }
122static inline int tick_program_event(ktime_t expires, int force) { return 0; }
123static inline void tick_oneshot_notify(void) { }
124static inline bool tick_oneshot_possible(void) { return false; }
125static inline int tick_oneshot_mode_active(void) { return 0; }
126static inline void tick_clock_notify(void) { }
127static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
128#endif /* !CONFIG_TICK_ONESHOT */
129
130/* Functions related to oneshot broadcasting */
131#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
132extern void tick_broadcast_switch_to_oneshot(void);
133extern int tick_broadcast_oneshot_active(void);
134extern void tick_check_oneshot_broadcast_this_cpu(void);
135bool tick_broadcast_oneshot_available(void);
136extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
137#else /* !(BROADCAST && ONESHOT): */
138static inline void tick_broadcast_switch_to_oneshot(void) { }
139static inline int tick_broadcast_oneshot_active(void) { return 0; }
140static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
141static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
142#endif /* !(BROADCAST && ONESHOT) */
143
144#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
145extern void tick_offline_cpu(unsigned int cpu);
146extern void tick_broadcast_offline(unsigned int cpu);
147#else
148static inline void tick_offline_cpu(unsigned int cpu) { }
149static inline void tick_broadcast_offline(unsigned int cpu) { }
150#endif
151
152/* NO_HZ_FULL internal */
153#ifdef CONFIG_NO_HZ_FULL
154extern void tick_nohz_init(void);
155# else
156static inline void tick_nohz_init(void) { }
157#endif
158
159#ifdef CONFIG_NO_HZ_COMMON
160extern unsigned long tick_nohz_active;
161extern void timers_update_nohz(void);
162extern u64 get_jiffies_update(unsigned long *basej);
163# ifdef CONFIG_SMP
164extern struct static_key_false timers_migration_enabled;
165extern void fetch_next_timer_interrupt_remote(unsigned long basej, u64 basem,
166 struct timer_events *tevt,
167 unsigned int cpu);
168extern void timer_lock_remote_bases(unsigned int cpu);
169extern void timer_unlock_remote_bases(unsigned int cpu);
170extern bool timer_base_is_idle(void);
171extern void timer_expire_remote(unsigned int cpu);
172# endif
173#else /* CONFIG_NO_HZ_COMMON */
174static inline void timers_update_nohz(void) { }
175#define tick_nohz_active (0)
176#endif
177
178DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
179
180extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem);
181u64 timer_base_try_to_set_idle(unsigned long basej, u64 basem, bool *idle);
182void timer_clear_idle(void);
183
184#define CLOCK_SET_WALL \
185 (BIT(HRTIMER_BASE_REALTIME) | BIT(HRTIMER_BASE_REALTIME_SOFT) | \
186 BIT(HRTIMER_BASE_TAI) | BIT(HRTIMER_BASE_TAI_SOFT))
187
188#define CLOCK_SET_BOOT \
189 (BIT(HRTIMER_BASE_BOOTTIME) | BIT(HRTIMER_BASE_BOOTTIME_SOFT))
190
191void clock_was_set(unsigned int bases);
192void clock_was_set_delayed(void);
193
194void hrtimers_resume_local(void);
195
196/* Since jiffies uses a simple TICK_NSEC multiplier
197 * conversion, the .shift value could be zero. However
198 * this would make NTP adjustments impossible as they are
199 * in units of 1/2^.shift. Thus we use JIFFIES_SHIFT to
200 * shift both the nominator and denominator the same
201 * amount, and give ntp adjustments in units of 1/2^8
202 *
203 * The value 8 is somewhat carefully chosen, as anything
204 * larger can result in overflows. TICK_NSEC grows as HZ
205 * shrinks, so values greater than 8 overflow 32bits when
206 * HZ=100.
207 */
208#if HZ < 34
209#define JIFFIES_SHIFT 6
210#elif HZ < 67
211#define JIFFIES_SHIFT 7
212#else
213#define JIFFIES_SHIFT 8
214#endif
215
216extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);