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 | struct 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 | |
21 | DECLARE_PER_CPU(struct tick_device, tick_cpu_device); |
22 | extern ktime_t tick_next_period; |
23 | extern int tick_do_timer_cpu __read_mostly; |
24 | |
25 | extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast); |
26 | extern void tick_handle_periodic(struct clock_event_device *dev); |
27 | extern void tick_check_new_device(struct clock_event_device *dev); |
28 | extern void tick_shutdown(unsigned int cpu); |
29 | extern void tick_suspend(void); |
30 | extern void tick_resume(void); |
31 | extern bool tick_check_replacement(struct clock_event_device *curdev, |
32 | struct clock_event_device *newdev); |
33 | extern void tick_install_replacement(struct clock_event_device *dev); |
34 | extern int tick_is_oneshot_available(void); |
35 | extern struct tick_device *tick_get_device(int cpu); |
36 | |
37 | extern int clockevents_tick_resume(struct clock_event_device *dev); |
38 | /* Check, if the device is functional or a dummy for broadcast */ |
39 | static inline int tick_device_is_functional(struct clock_event_device *dev) |
40 | { |
41 | return !(dev->features & CLOCK_EVT_FEAT_DUMMY); |
42 | } |
43 | |
44 | static inline enum clock_event_state clockevent_get_state(struct clock_event_device *dev) |
45 | { |
46 | return dev->state_use_accessors; |
47 | } |
48 | |
49 | static 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 | |
55 | extern void clockevents_shutdown(struct clock_event_device *dev); |
56 | extern void clockevents_exchange_device(struct clock_event_device *old, |
57 | struct clock_event_device *new); |
58 | extern void clockevents_switch_state(struct clock_event_device *dev, |
59 | enum clock_event_state state); |
60 | extern int clockevents_program_event(struct clock_event_device *dev, |
61 | ktime_t expires, bool force); |
62 | extern void clockevents_handle_noop(struct clock_event_device *dev); |
63 | extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq); |
64 | |
65 | /* Broadcasting support */ |
66 | # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST |
67 | extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu); |
68 | extern void tick_install_broadcast_device(struct clock_event_device *dev, int cpu); |
69 | extern int tick_is_broadcast_device(struct clock_event_device *dev); |
70 | extern void tick_suspend_broadcast(void); |
71 | extern void tick_resume_broadcast(void); |
72 | extern bool tick_resume_check_broadcast(void); |
73 | extern void tick_broadcast_init(void); |
74 | extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast); |
75 | extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq); |
76 | extern struct tick_device *tick_get_broadcast_device(void); |
77 | extern struct cpumask *tick_get_broadcast_mask(void); |
78 | extern const struct clock_event_device *tick_get_wakeup_device(int cpu); |
79 | # else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */ |
80 | static inline void tick_install_broadcast_device(struct clock_event_device *dev, int cpu) { } |
81 | static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; } |
82 | static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; } |
83 | static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { } |
84 | static inline void tick_suspend_broadcast(void) { } |
85 | static inline void tick_resume_broadcast(void) { } |
86 | static inline bool tick_resume_check_broadcast(void) { return false; } |
87 | static inline void tick_broadcast_init(void) { } |
88 | static 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 */ |
91 | static 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: */ |
98 | static inline void tick_suspend(void) { } |
99 | static inline void tick_resume(void) { } |
100 | #endif /* !GENERIC_CLOCKEVENTS */ |
101 | |
102 | /* Oneshot related functions */ |
103 | #ifdef CONFIG_TICK_ONESHOT |
104 | extern void tick_setup_oneshot(struct clock_event_device *newdev, |
105 | void (*handler)(struct clock_event_device *), |
106 | ktime_t nextevt); |
107 | extern int tick_program_event(ktime_t expires, int force); |
108 | extern void tick_oneshot_notify(void); |
109 | extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *)); |
110 | extern void tick_resume_oneshot(void); |
111 | static inline bool tick_oneshot_possible(void) { return true; } |
112 | extern int tick_oneshot_mode_active(void); |
113 | extern void tick_clock_notify(void); |
114 | extern int tick_check_oneshot_change(int allow_nohz); |
115 | extern int tick_init_highres(void); |
116 | #else /* !CONFIG_TICK_ONESHOT: */ |
117 | static inline |
118 | void tick_setup_oneshot(struct clock_event_device *newdev, |
119 | void (*handler)(struct clock_event_device *), |
120 | ktime_t nextevt) { BUG(); } |
121 | static inline void tick_resume_oneshot(void) { BUG(); } |
122 | static inline int tick_program_event(ktime_t expires, int force) { return 0; } |
123 | static inline void tick_oneshot_notify(void) { } |
124 | static inline bool tick_oneshot_possible(void) { return false; } |
125 | static inline int tick_oneshot_mode_active(void) { return 0; } |
126 | static inline void tick_clock_notify(void) { } |
127 | static 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) |
132 | extern void tick_broadcast_switch_to_oneshot(void); |
133 | extern int tick_broadcast_oneshot_active(void); |
134 | extern void tick_check_oneshot_broadcast_this_cpu(void); |
135 | bool tick_broadcast_oneshot_available(void); |
136 | extern struct cpumask *tick_get_broadcast_oneshot_mask(void); |
137 | #else /* !(BROADCAST && ONESHOT): */ |
138 | static inline void tick_broadcast_switch_to_oneshot(void) { } |
139 | static inline int tick_broadcast_oneshot_active(void) { return 0; } |
140 | static inline void tick_check_oneshot_broadcast_this_cpu(void) { } |
141 | static 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) |
145 | extern void tick_offline_cpu(unsigned int cpu); |
146 | extern void tick_broadcast_offline(unsigned int cpu); |
147 | #else |
148 | static inline void tick_offline_cpu(unsigned int cpu) { } |
149 | static inline void tick_broadcast_offline(unsigned int cpu) { } |
150 | #endif |
151 | |
152 | /* NO_HZ_FULL internal */ |
153 | #ifdef CONFIG_NO_HZ_FULL |
154 | extern void tick_nohz_init(void); |
155 | # else |
156 | static inline void tick_nohz_init(void) { } |
157 | #endif |
158 | |
159 | #ifdef CONFIG_NO_HZ_COMMON |
160 | extern unsigned long tick_nohz_active; |
161 | extern void timers_update_nohz(void); |
162 | extern u64 get_jiffies_update(unsigned long *basej); |
163 | # ifdef CONFIG_SMP |
164 | extern struct static_key_false timers_migration_enabled; |
165 | extern void fetch_next_timer_interrupt_remote(unsigned long basej, u64 basem, |
166 | struct timer_events *tevt, |
167 | unsigned int cpu); |
168 | extern void timer_lock_remote_bases(unsigned int cpu); |
169 | extern void timer_unlock_remote_bases(unsigned int cpu); |
170 | extern bool timer_base_is_idle(void); |
171 | extern void timer_expire_remote(unsigned int cpu); |
172 | # endif |
173 | #else /* CONFIG_NO_HZ_COMMON */ |
174 | static inline void timers_update_nohz(void) { } |
175 | #define tick_nohz_active (0) |
176 | #endif |
177 | |
178 | DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases); |
179 | |
180 | extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem); |
181 | u64 timer_base_try_to_set_idle(unsigned long basej, u64 basem, bool *idle); |
182 | void 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 | |
191 | void clock_was_set(unsigned int bases); |
192 | void clock_was_set_delayed(void); |
193 | |
194 | void 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 | |
216 | extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt); |
217 | |