xref: /linux-6.15/include/linux/hrtimer_defs.h (revision 1a4729ec)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_HRTIMER_DEFS_H
3 #define _LINUX_HRTIMER_DEFS_H
4 
5 #include <linux/ktime.h>
6 #include <linux/timerqueue.h>
7 #include <linux/seqlock.h>
8 
9 #ifdef CONFIG_HIGH_RES_TIMERS
10 
11 /*
12  * The resolution of the clocks. The resolution value is returned in
13  * the clock_getres() system call to give application programmers an
14  * idea of the (in)accuracy of timers. Timer values are rounded up to
15  * this resolution values.
16  */
17 # define HIGH_RES_NSEC		1
18 # define KTIME_HIGH_RES		(HIGH_RES_NSEC)
19 # define MONOTONIC_RES_NSEC	HIGH_RES_NSEC
20 # define KTIME_MONOTONIC_RES	KTIME_HIGH_RES
21 
22 #else
23 
24 # define MONOTONIC_RES_NSEC	LOW_RES_NSEC
25 # define KTIME_MONOTONIC_RES	KTIME_LOW_RES
26 
27 #endif
28 
29 #ifdef CONFIG_64BIT
30 # define __hrtimer_clock_base_align	____cacheline_aligned
31 #else
32 # define __hrtimer_clock_base_align
33 #endif
34 
35 /**
36  * struct hrtimer_clock_base - the timer base for a specific clock
37  * @cpu_base:		per cpu clock base
38  * @index:		clock type index for per_cpu support when moving a
39  *			timer to a base on another cpu.
40  * @clockid:		clock id for per_cpu support
41  * @seq:		seqcount around __run_hrtimer
42  * @running:		pointer to the currently running hrtimer
43  * @active:		red black tree root node for the active timers
44  * @get_time:		function to retrieve the current time of the clock
45  * @offset:		offset of this clock to the monotonic base
46  */
47 struct hrtimer_clock_base {
48 	struct hrtimer_cpu_base	*cpu_base;
49 	unsigned int		index;
50 	clockid_t		clockid;
51 	seqcount_raw_spinlock_t	seq;
52 	struct hrtimer		*running;
53 	struct timerqueue_head	active;
54 	ktime_t			(*get_time)(void);
55 	ktime_t			offset;
56 } __hrtimer_clock_base_align;
57 
58 enum  hrtimer_base_type {
59 	HRTIMER_BASE_MONOTONIC,
60 	HRTIMER_BASE_REALTIME,
61 	HRTIMER_BASE_BOOTTIME,
62 	HRTIMER_BASE_TAI,
63 	HRTIMER_BASE_MONOTONIC_SOFT,
64 	HRTIMER_BASE_REALTIME_SOFT,
65 	HRTIMER_BASE_BOOTTIME_SOFT,
66 	HRTIMER_BASE_TAI_SOFT,
67 	HRTIMER_MAX_CLOCK_BASES,
68 };
69 
70 /**
71  * struct hrtimer_cpu_base - the per cpu clock bases
72  * @lock:		lock protecting the base and associated clock bases
73  *			and timers
74  * @cpu:		cpu number
75  * @active_bases:	Bitfield to mark bases with active timers
76  * @clock_was_set_seq:	Sequence counter of clock was set events
77  * @hres_active:	State of high resolution mode
78  * @in_hrtirq:		hrtimer_interrupt() is currently executing
79  * @hang_detected:	The last hrtimer interrupt detected a hang
80  * @softirq_activated:	displays, if the softirq is raised - update of softirq
81  *			related settings is not required then.
82  * @nr_events:		Total number of hrtimer interrupt events
83  * @nr_retries:		Total number of hrtimer interrupt retries
84  * @nr_hangs:		Total number of hrtimer interrupt hangs
85  * @max_hang_time:	Maximum time spent in hrtimer_interrupt
86  * @softirq_expiry_lock: Lock which is taken while softirq based hrtimer are
87  *			 expired
88  * @timer_waiters:	A hrtimer_cancel() invocation waits for the timer
89  *			callback to finish.
90  * @expires_next:	absolute time of the next event, is required for remote
91  *			hrtimer enqueue; it is the total first expiry time (hard
92  *			and soft hrtimer are taken into account)
93  * @next_timer:		Pointer to the first expiring timer
94  * @softirq_expires_next: Time to check, if soft queues needs also to be expired
95  * @softirq_next_timer: Pointer to the first expiring softirq based timer
96  * @clock_base:		array of clock bases for this cpu
97  *
98  * Note: next_timer is just an optimization for __remove_hrtimer().
99  *	 Do not dereference the pointer because it is not reliable on
100  *	 cross cpu removals.
101  */
102 struct hrtimer_cpu_base {
103 	raw_spinlock_t			lock;
104 	unsigned int			cpu;
105 	unsigned int			active_bases;
106 	unsigned int			clock_was_set_seq;
107 	unsigned int			hres_active		: 1,
108 					in_hrtirq		: 1,
109 					hang_detected		: 1,
110 					softirq_activated       : 1;
111 #ifdef CONFIG_HIGH_RES_TIMERS
112 	unsigned int			nr_events;
113 	unsigned short			nr_retries;
114 	unsigned short			nr_hangs;
115 	unsigned int			max_hang_time;
116 #endif
117 #ifdef CONFIG_PREEMPT_RT
118 	spinlock_t			softirq_expiry_lock;
119 	atomic_t			timer_waiters;
120 #endif
121 	ktime_t				expires_next;
122 	struct hrtimer			*next_timer;
123 	ktime_t				softirq_expires_next;
124 	struct hrtimer			*softirq_next_timer;
125 	struct hrtimer_clock_base	clock_base[HRTIMER_MAX_CLOCK_BASES];
126 } ____cacheline_aligned;
127 
128 
129 #endif
130