1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _TICK_SCHED_H |
3 | #define _TICK_SCHED_H |
4 | |
5 | #include <linux/hrtimer.h> |
6 | |
7 | enum tick_device_mode { |
8 | TICKDEV_MODE_PERIODIC, |
9 | TICKDEV_MODE_ONESHOT, |
10 | }; |
11 | |
12 | struct tick_device { |
13 | struct clock_event_device *evtdev; |
14 | enum tick_device_mode mode; |
15 | }; |
16 | |
17 | enum tick_nohz_mode { |
18 | NOHZ_MODE_INACTIVE, |
19 | NOHZ_MODE_LOWRES, |
20 | NOHZ_MODE_HIGHRES, |
21 | }; |
22 | |
23 | /** |
24 | * struct tick_sched - sched tick emulation and no idle tick control/stats |
25 | * |
26 | * @inidle: Indicator that the CPU is in the tick idle mode |
27 | * @tick_stopped: Indicator that the idle tick has been stopped |
28 | * @idle_active: Indicator that the CPU is actively in the tick idle mode; |
29 | * it is reset during irq handling phases. |
30 | * @do_timer_last: CPU was the last one doing do_timer before going idle |
31 | * @got_idle_tick: Tick timer function has run with @inidle set |
32 | * @stalled_jiffies: Number of stalled jiffies detected across ticks |
33 | * @last_tick_jiffies: Value of jiffies seen on last tick |
34 | * @sched_timer: hrtimer to schedule the periodic tick in high |
35 | * resolution mode |
36 | * @last_tick: Store the last tick expiry time when the tick |
37 | * timer is modified for nohz sleeps. This is necessary |
38 | * to resume the tick timer operation in the timeline |
39 | * when the CPU returns from nohz sleep. |
40 | * @next_tick: Next tick to be fired when in dynticks mode. |
41 | * @idle_jiffies: jiffies at the entry to idle for idle time accounting |
42 | * @idle_waketime: Time when the idle was interrupted |
43 | * @idle_entrytime: Time when the idle call was entered |
44 | * @nohz_mode: Mode - one state of tick_nohz_mode |
45 | * @last_jiffies: Base jiffies snapshot when next event was last computed |
46 | * @timer_expires_base: Base time clock monotonic for @timer_expires |
47 | * @timer_expires: Anticipated timer expiration time (in case sched tick is stopped) |
48 | * @next_timer: Expiry time of next expiring timer for debugging purpose only |
49 | * @idle_expires: Next tick in idle, for debugging purpose only |
50 | * @idle_calls: Total number of idle calls |
51 | * @idle_sleeps: Number of idle calls, where the sched tick was stopped |
52 | * @idle_exittime: Time when the idle state was left |
53 | * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped |
54 | * @iowait_sleeptime: Sum of the time slept in idle with sched tick stopped, with IO outstanding |
55 | * @tick_dep_mask: Tick dependency mask - is set, if someone needs the tick |
56 | * @check_clocks: Notification mechanism about clocksource changes |
57 | */ |
58 | struct tick_sched { |
59 | /* Common flags */ |
60 | unsigned int inidle : 1; |
61 | unsigned int tick_stopped : 1; |
62 | unsigned int idle_active : 1; |
63 | unsigned int do_timer_last : 1; |
64 | unsigned int got_idle_tick : 1; |
65 | |
66 | /* Tick handling: jiffies stall check */ |
67 | unsigned int stalled_jiffies; |
68 | unsigned long last_tick_jiffies; |
69 | |
70 | /* Tick handling */ |
71 | struct hrtimer sched_timer; |
72 | ktime_t last_tick; |
73 | ktime_t next_tick; |
74 | unsigned long idle_jiffies; |
75 | ktime_t idle_waketime; |
76 | |
77 | /* Idle entry */ |
78 | seqcount_t idle_sleeptime_seq; |
79 | ktime_t idle_entrytime; |
80 | |
81 | /* Tick stop */ |
82 | enum tick_nohz_mode nohz_mode; |
83 | unsigned long last_jiffies; |
84 | u64 timer_expires_base; |
85 | u64 timer_expires; |
86 | u64 next_timer; |
87 | ktime_t idle_expires; |
88 | unsigned long idle_calls; |
89 | unsigned long idle_sleeps; |
90 | |
91 | /* Idle exit */ |
92 | ktime_t idle_exittime; |
93 | ktime_t idle_sleeptime; |
94 | ktime_t iowait_sleeptime; |
95 | |
96 | /* Full dynticks handling */ |
97 | atomic_t tick_dep_mask; |
98 | |
99 | /* Clocksource changes */ |
100 | unsigned long check_clocks; |
101 | }; |
102 | |
103 | extern struct tick_sched *tick_get_tick_sched(int cpu); |
104 | |
105 | extern void tick_setup_sched_timer(void); |
106 | #if defined CONFIG_NO_HZ_COMMON || defined CONFIG_HIGH_RES_TIMERS |
107 | extern void tick_cancel_sched_timer(int cpu); |
108 | #else |
109 | static inline void tick_cancel_sched_timer(int cpu) { } |
110 | #endif |
111 | |
112 | #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST |
113 | extern int __tick_broadcast_oneshot_control(enum tick_broadcast_state state); |
114 | #else |
115 | static inline int |
116 | __tick_broadcast_oneshot_control(enum tick_broadcast_state state) |
117 | { |
118 | return -EBUSY; |
119 | } |
120 | #endif |
121 | |
122 | #endif |
123 | |