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