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 /* The CPU is in the tick idle mode */ 18 #define TS_FLAG_INIDLE BIT(0) 19 /* The idle tick has been stopped */ 20 #define TS_FLAG_STOPPED BIT(1) 21 /* 22 * Indicator that the CPU is actively in the tick idle mode; 23 * it is reset during irq handling phases. 24 */ 25 #define TS_FLAG_IDLE_ACTIVE BIT(2) 26 /* CPU was the last one doing do_timer before going idle */ 27 #define TS_FLAG_DO_TIMER_LAST BIT(3) 28 /* NO_HZ is enabled */ 29 #define TS_FLAG_NOHZ BIT(4) 30 /* High resolution tick mode */ 31 #define TS_FLAG_HIGHRES BIT(5) 32 33 /** 34 * struct tick_sched - sched tick emulation and no idle tick control/stats 35 * 36 * @flags: State flags gathering the TS_FLAG_* features 37 * @got_idle_tick: Tick timer function has run with @inidle set 38 * @stalled_jiffies: Number of stalled jiffies detected across ticks 39 * @last_tick_jiffies: Value of jiffies seen on last tick 40 * @sched_timer: hrtimer to schedule the periodic tick in high 41 * resolution mode 42 * @last_tick: Store the last tick expiry time when the tick 43 * timer is modified for nohz sleeps. This is necessary 44 * to resume the tick timer operation in the timeline 45 * when the CPU returns from nohz sleep. 46 * @next_tick: Next tick to be fired when in dynticks mode. 47 * @idle_jiffies: jiffies at the entry to idle for idle time accounting 48 * @idle_waketime: Time when the idle was interrupted 49 * @idle_sleeptime_seq: sequence counter for data consistency 50 * @idle_entrytime: Time when the idle call was entered 51 * @last_jiffies: Base jiffies snapshot when next event was last computed 52 * @timer_expires_base: Base time clock monotonic for @timer_expires 53 * @timer_expires: Anticipated timer expiration time (in case sched tick is stopped) 54 * @next_timer: Expiry time of next expiring timer for debugging purpose only 55 * @idle_expires: Next tick in idle, for debugging purpose only 56 * @idle_calls: Total number of idle calls 57 * @idle_sleeps: Number of idle calls, where the sched tick was stopped 58 * @idle_exittime: Time when the idle state was left 59 * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped 60 * @iowait_sleeptime: Sum of the time slept in idle with sched tick stopped, with IO outstanding 61 * @tick_dep_mask: Tick dependency mask - is set, if someone needs the tick 62 * @check_clocks: Notification mechanism about clocksource changes 63 */ 64 struct tick_sched { 65 /* Common flags */ 66 unsigned long flags; 67 68 /* Tick handling: jiffies stall check */ 69 unsigned int stalled_jiffies; 70 unsigned long last_tick_jiffies; 71 72 /* Tick handling */ 73 struct hrtimer sched_timer; 74 ktime_t last_tick; 75 ktime_t next_tick; 76 unsigned long idle_jiffies; 77 ktime_t idle_waketime; 78 unsigned int got_idle_tick; 79 80 /* Idle entry */ 81 seqcount_t idle_sleeptime_seq; 82 ktime_t idle_entrytime; 83 84 /* Tick stop */ 85 unsigned long last_jiffies; 86 u64 timer_expires_base; 87 u64 timer_expires; 88 u64 next_timer; 89 ktime_t idle_expires; 90 unsigned long idle_calls; 91 unsigned long idle_sleeps; 92 93 /* Idle exit */ 94 ktime_t idle_exittime; 95 ktime_t idle_sleeptime; 96 ktime_t iowait_sleeptime; 97 98 /* Full dynticks handling */ 99 atomic_t tick_dep_mask; 100 101 /* Clocksource changes */ 102 unsigned long check_clocks; 103 }; 104 105 extern struct tick_sched *tick_get_tick_sched(int cpu); 106 107 extern void tick_setup_sched_timer(bool hrtimer); 108 #if defined CONFIG_TICK_ONESHOT 109 extern void tick_sched_timer_dying(int cpu); 110 #else tick_sched_timer_dying(int cpu)111static inline void tick_sched_timer_dying(int cpu) { } 112 #endif 113 114 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 115 extern int __tick_broadcast_oneshot_control(enum tick_broadcast_state state); 116 #else 117 static inline int __tick_broadcast_oneshot_control(enum tick_broadcast_state state)118__tick_broadcast_oneshot_control(enum tick_broadcast_state state) 119 { 120 return -EBUSY; 121 } 122 #endif 123 124 #endif 125