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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);
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);
1/*
2 * tick internal variable and functions used by low/high res code
3 */
4#include <linux/hrtimer.h>
5#include <linux/tick.h>
6
7#ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD
8
9#define TICK_DO_TIMER_NONE -1
10#define TICK_DO_TIMER_BOOT -2
11
12DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
13extern ktime_t tick_next_period;
14extern ktime_t tick_period;
15extern int tick_do_timer_cpu __read_mostly;
16
17extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
18extern void tick_handle_periodic(struct clock_event_device *dev);
19
20extern void clockevents_shutdown(struct clock_event_device *dev);
21
22/*
23 * NO_HZ / high resolution timer shared code
24 */
25#ifdef CONFIG_TICK_ONESHOT
26extern void tick_setup_oneshot(struct clock_event_device *newdev,
27 void (*handler)(struct clock_event_device *),
28 ktime_t nextevt);
29extern int tick_dev_program_event(struct clock_event_device *dev,
30 ktime_t expires, int force);
31extern int tick_program_event(ktime_t expires, int force);
32extern void tick_oneshot_notify(void);
33extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
34extern void tick_resume_oneshot(void);
35# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
36extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
37extern void tick_broadcast_oneshot_control(unsigned long reason);
38extern void tick_broadcast_switch_to_oneshot(void);
39extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup);
40extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc);
41extern int tick_broadcast_oneshot_active(void);
42extern void tick_check_oneshot_broadcast(int cpu);
43bool tick_broadcast_oneshot_available(void);
44# else /* BROADCAST */
45static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
46{
47 BUG();
48}
49static inline void tick_broadcast_oneshot_control(unsigned long reason) { }
50static inline void tick_broadcast_switch_to_oneshot(void) { }
51static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
52static inline int tick_broadcast_oneshot_active(void) { return 0; }
53static inline void tick_check_oneshot_broadcast(int cpu) { }
54static inline bool tick_broadcast_oneshot_available(void) { return true; }
55# endif /* !BROADCAST */
56
57#else /* !ONESHOT */
58static inline
59void tick_setup_oneshot(struct clock_event_device *newdev,
60 void (*handler)(struct clock_event_device *),
61 ktime_t nextevt)
62{
63 BUG();
64}
65static inline void tick_resume_oneshot(void)
66{
67 BUG();
68}
69static inline int tick_program_event(ktime_t expires, int force)
70{
71 return 0;
72}
73static inline void tick_oneshot_notify(void) { }
74static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
75{
76 BUG();
77}
78static inline void tick_broadcast_oneshot_control(unsigned long reason) { }
79static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
80static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
81{
82 return 0;
83}
84static inline int tick_broadcast_oneshot_active(void) { return 0; }
85static inline bool tick_broadcast_oneshot_available(void) { return false; }
86#endif /* !TICK_ONESHOT */
87
88/*
89 * Broadcasting support
90 */
91#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
92extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
93extern int tick_check_broadcast_device(struct clock_event_device *dev);
94extern int tick_is_broadcast_device(struct clock_event_device *dev);
95extern void tick_broadcast_on_off(unsigned long reason, int *oncpu);
96extern void tick_shutdown_broadcast(unsigned int *cpup);
97extern void tick_suspend_broadcast(void);
98extern int tick_resume_broadcast(void);
99
100extern void
101tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
102
103#else /* !BROADCAST */
104
105static inline int tick_check_broadcast_device(struct clock_event_device *dev)
106{
107 return 0;
108}
109
110static inline int tick_is_broadcast_device(struct clock_event_device *dev)
111{
112 return 0;
113}
114static inline int tick_device_uses_broadcast(struct clock_event_device *dev,
115 int cpu)
116{
117 return 0;
118}
119static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
120static inline void tick_broadcast_on_off(unsigned long reason, int *oncpu) { }
121static inline void tick_shutdown_broadcast(unsigned int *cpup) { }
122static inline void tick_suspend_broadcast(void) { }
123static inline int tick_resume_broadcast(void) { return 0; }
124
125/*
126 * Set the periodic handler in non broadcast mode
127 */
128static inline void tick_set_periodic_handler(struct clock_event_device *dev,
129 int broadcast)
130{
131 dev->event_handler = tick_handle_periodic;
132}
133#endif /* !BROADCAST */
134
135/*
136 * Check, if the device is functional or a dummy for broadcast
137 */
138static inline int tick_device_is_functional(struct clock_event_device *dev)
139{
140 return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
141}
142
143#endif
144
145extern void do_timer(unsigned long ticks);
146extern seqlock_t xtime_lock;