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/*
  2 * tick internal variable and functions used by low/high res code
  3 */
  4#include <linux/hrtimer.h>
  5#include <linux/tick.h>
  6
  7extern seqlock_t jiffies_lock;
 
  8
  9#define CS_NAME_LEN	32
 10
 11#ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD
 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 ktime_t tick_period;
 19extern int tick_do_timer_cpu __read_mostly;
 20
 21extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
 22extern void tick_handle_periodic(struct clock_event_device *dev);
 23extern void tick_check_new_device(struct clock_event_device *dev);
 24extern void tick_handover_do_timer(int *cpup);
 25extern void tick_shutdown(unsigned int *cpup);
 26extern void tick_suspend(void);
 27extern void tick_resume(void);
 28extern bool tick_check_replacement(struct clock_event_device *curdev,
 29				   struct clock_event_device *newdev);
 30extern void tick_install_replacement(struct clock_event_device *dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 31
 32extern void clockevents_shutdown(struct clock_event_device *dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 33
 34extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
 
 
 
 35
 36/*
 37 * NO_HZ / high resolution timer shared code
 38 */
 39#ifdef CONFIG_TICK_ONESHOT
 40extern void tick_setup_oneshot(struct clock_event_device *newdev,
 41			       void (*handler)(struct clock_event_device *),
 42			       ktime_t nextevt);
 43extern int tick_program_event(ktime_t expires, int force);
 44extern void tick_oneshot_notify(void);
 45extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
 46extern void tick_resume_oneshot(void);
 47# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
 48extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
 49extern int tick_broadcast_oneshot_control(unsigned long reason);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 50extern void tick_broadcast_switch_to_oneshot(void);
 51extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup);
 52extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc);
 53extern int tick_broadcast_oneshot_active(void);
 54extern void tick_check_oneshot_broadcast_this_cpu(void);
 55bool tick_broadcast_oneshot_available(void);
 56# else /* BROADCAST */
 57static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
 58{
 59	BUG();
 60}
 61static inline int tick_broadcast_oneshot_control(unsigned long reason) { return 0; }
 62static inline void tick_broadcast_switch_to_oneshot(void) { }
 63static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
 64static inline int tick_broadcast_oneshot_active(void) { return 0; }
 65static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
 66static inline bool tick_broadcast_oneshot_available(void) { return true; }
 67# endif /* !BROADCAST */
 68
 69#else /* !ONESHOT */
 70static inline
 71void tick_setup_oneshot(struct clock_event_device *newdev,
 72			void (*handler)(struct clock_event_device *),
 73			ktime_t nextevt)
 74{
 75	BUG();
 76}
 77static inline void tick_resume_oneshot(void)
 78{
 79	BUG();
 80}
 81static inline int tick_program_event(ktime_t expires, int force)
 82{
 83	return 0;
 84}
 85static inline void tick_oneshot_notify(void) { }
 86static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
 87{
 88	BUG();
 89}
 90static inline int tick_broadcast_oneshot_control(unsigned long reason) { return 0; }
 91static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
 92static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
 93{
 94	return 0;
 95}
 96static inline int tick_broadcast_oneshot_active(void) { return 0; }
 97static inline bool tick_broadcast_oneshot_available(void) { return false; }
 98#endif /* !TICK_ONESHOT */
 99
100/*
101 * Broadcasting support
102 */
103#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
104extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
105extern void tick_install_broadcast_device(struct clock_event_device *dev);
106extern int tick_is_broadcast_device(struct clock_event_device *dev);
107extern void tick_broadcast_on_off(unsigned long reason, int *oncpu);
108extern void tick_shutdown_broadcast(unsigned int *cpup);
109extern void tick_suspend_broadcast(void);
110extern int tick_resume_broadcast(void);
111extern void tick_broadcast_init(void);
112extern void
113tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
114int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
115
116#else /* !BROADCAST */
117
118static inline void tick_install_broadcast_device(struct clock_event_device *dev)
119{
120}
 
 
 
 
 
121
122static inline int tick_is_broadcast_device(struct clock_event_device *dev)
123{
124	return 0;
125}
126static inline int tick_device_uses_broadcast(struct clock_event_device *dev,
127					     int cpu)
128{
129	return 0;
130}
131static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
132static inline void tick_broadcast_on_off(unsigned long reason, int *oncpu) { }
133static inline void tick_shutdown_broadcast(unsigned int *cpup) { }
134static inline void tick_suspend_broadcast(void) { }
135static inline int tick_resume_broadcast(void) { return 0; }
136static inline void tick_broadcast_init(void) { }
137static inline int tick_broadcast_update_freq(struct clock_event_device *dev,
138					     u32 freq) { return -ENODEV; }
139
140/*
141 * Set the periodic handler in non broadcast mode
142 */
143static inline void tick_set_periodic_handler(struct clock_event_device *dev,
144					     int broadcast)
145{
146	dev->event_handler = tick_handle_periodic;
147}
148#endif /* !BROADCAST */
149
150/*
151 * Check, if the device is functional or a dummy for broadcast
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
152 */
153static inline int tick_device_is_functional(struct clock_event_device *dev)
154{
155	return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
156}
157
158int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
159
160#endif
161
162extern void do_timer(unsigned long ticks);
163extern void update_wall_time(void);