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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
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);
59
60/* Broadcasting support */
61# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
62extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
63extern void tick_install_broadcast_device(struct clock_event_device *dev, int cpu);
64extern int tick_is_broadcast_device(struct clock_event_device *dev);
65extern void tick_suspend_broadcast(void);
66extern void tick_resume_broadcast(void);
67extern bool tick_resume_check_broadcast(void);
68extern void tick_broadcast_init(void);
69extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
70extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
71extern struct tick_device *tick_get_broadcast_device(void);
72extern struct cpumask *tick_get_broadcast_mask(void);
73extern const struct clock_event_device *tick_get_wakeup_device(int cpu);
74# else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
75static inline void tick_install_broadcast_device(struct clock_event_device *dev, int cpu) { }
76static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
77static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
78static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
79static inline void tick_suspend_broadcast(void) { }
80static inline void tick_resume_broadcast(void) { }
81static inline bool tick_resume_check_broadcast(void) { return false; }
82static inline void tick_broadcast_init(void) { }
83static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }
84
85/* Set the periodic handler in non broadcast mode */
86static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
87{
88 dev->event_handler = tick_handle_periodic;
89}
90# endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
91
92#else /* !GENERIC_CLOCKEVENTS: */
93static inline void tick_suspend(void) { }
94static inline void tick_resume(void) { }
95#endif /* !GENERIC_CLOCKEVENTS */
96
97/* Oneshot related functions */
98#ifdef CONFIG_TICK_ONESHOT
99extern void tick_setup_oneshot(struct clock_event_device *newdev,
100 void (*handler)(struct clock_event_device *),
101 ktime_t nextevt);
102extern int tick_program_event(ktime_t expires, int force);
103extern void tick_oneshot_notify(void);
104extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
105extern void tick_resume_oneshot(void);
106static inline bool tick_oneshot_possible(void) { return true; }
107extern int tick_oneshot_mode_active(void);
108extern void tick_clock_notify(void);
109extern int tick_check_oneshot_change(int allow_nohz);
110extern int tick_init_highres(void);
111#else /* !CONFIG_TICK_ONESHOT: */
112static inline
113void tick_setup_oneshot(struct clock_event_device *newdev,
114 void (*handler)(struct clock_event_device *),
115 ktime_t nextevt) { BUG(); }
116static inline void tick_resume_oneshot(void) { BUG(); }
117static inline int tick_program_event(ktime_t expires, int force) { return 0; }
118static inline void tick_oneshot_notify(void) { }
119static inline bool tick_oneshot_possible(void) { return false; }
120static inline int tick_oneshot_mode_active(void) { return 0; }
121static inline void tick_clock_notify(void) { }
122static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
123#endif /* !CONFIG_TICK_ONESHOT */
124
125/* Functions related to oneshot broadcasting */
126#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
127extern void tick_broadcast_switch_to_oneshot(void);
128extern int tick_broadcast_oneshot_active(void);
129extern void tick_check_oneshot_broadcast_this_cpu(void);
130bool tick_broadcast_oneshot_available(void);
131extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
132#else /* !(BROADCAST && ONESHOT): */
133static inline void tick_broadcast_switch_to_oneshot(void) { }
134static inline int tick_broadcast_oneshot_active(void) { return 0; }
135static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
136static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
137#endif /* !(BROADCAST && ONESHOT) */
138
139#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
140extern void tick_broadcast_offline(unsigned int cpu);
141#else
142static inline void tick_broadcast_offline(unsigned int cpu) { }
143#endif
144
145/* NO_HZ_FULL internal */
146#ifdef CONFIG_NO_HZ_FULL
147extern void tick_nohz_init(void);
148# else
149static inline void tick_nohz_init(void) { }
150#endif
151
152#ifdef CONFIG_NO_HZ_COMMON
153extern unsigned long tick_nohz_active;
154extern void timers_update_nohz(void);
155# ifdef CONFIG_SMP
156extern struct static_key_false timers_migration_enabled;
157# endif
158#else /* CONFIG_NO_HZ_COMMON */
159static inline void timers_update_nohz(void) { }
160#define tick_nohz_active (0)
161#endif
162
163DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
164
165extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem);
166void timer_clear_idle(void);
167
168#define CLOCK_SET_WALL \
169 (BIT(HRTIMER_BASE_REALTIME) | BIT(HRTIMER_BASE_REALTIME_SOFT) | \
170 BIT(HRTIMER_BASE_TAI) | BIT(HRTIMER_BASE_TAI_SOFT))
171
172#define CLOCK_SET_BOOT \
173 (BIT(HRTIMER_BASE_BOOTTIME) | BIT(HRTIMER_BASE_BOOTTIME_SOFT))
174
175void clock_was_set(unsigned int bases);
176void clock_was_set_delayed(void);
177
178void hrtimers_resume_local(void);
179
180/* Since jiffies uses a simple TICK_NSEC multiplier
181 * conversion, the .shift value could be zero. However
182 * this would make NTP adjustments impossible as they are
183 * in units of 1/2^.shift. Thus we use JIFFIES_SHIFT to
184 * shift both the nominator and denominator the same
185 * amount, and give ntp adjustments in units of 1/2^8
186 *
187 * The value 8 is somewhat carefully chosen, as anything
188 * larger can result in overflows. TICK_NSEC grows as HZ
189 * shrinks, so values greater than 8 overflow 32bits when
190 * HZ=100.
191 */
192#if HZ < 34
193#define JIFFIES_SHIFT 6
194#elif HZ < 67
195#define JIFFIES_SHIFT 7
196#else
197#define JIFFIES_SHIFT 8
198#endif
199
200extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);