/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _TICK_SCHED_H
#define _TICK_SCHED_H
#include <linux/hrtimer.h>
enum tick_device_mode {
TICKDEV_MODE_PERIODIC,
TICKDEV_MODE_ONESHOT,
};
struct tick_device {
struct clock_event_device *evtdev;
enum tick_device_mode mode;
};
/* The CPU is in the tick idle mode */
#define TS_FLAG_INIDLE BIT(0)
/* The idle tick has been stopped */
#define TS_FLAG_STOPPED BIT(1)
/*
* Indicator that the CPU is actively in the tick idle mode;
* it is reset during irq handling phases.
*/
#define TS_FLAG_IDLE_ACTIVE BIT(2)
/* CPU was the last one doing do_timer before going idle */
#define TS_FLAG_DO_TIMER_LAST BIT(3)
/* NO_HZ is enabled */
#define TS_FLAG_NOHZ BIT(4)
/* High resolution tick mode */
#define TS_FLAG_HIGHRES BIT(5)
/**
* struct tick_sched - sched tick emulation and no idle tick control/stats
*
* @flags: State flags gathering the TS_FLAG_* features
* @got_idle_tick: Tick timer function has run with @inidle set
* @stalled_jiffies: Number of stalled jiffies detected across ticks
* @last_tick_jiffies: Value of jiffies seen on last tick
* @sched_timer: hrtimer to schedule the periodic tick in high
* resolution mode
* @last_tick: Store the last tick expiry time when the tick
* timer is modified for nohz sleeps. This is necessary
* to resume the tick timer operation in the timeline
* when the CPU returns from nohz sleep.
* @next_tick: Next tick to be fired when in dynticks mode.
* @idle_jiffies: jiffies at the entry to idle for idle time accounting
* @idle_waketime: Time when the idle was interrupted
* @idle_sleeptime_seq: sequence counter for data consistency
* @idle_entrytime: Time when the idle call was entered
* @last_jiffies: Base jiffies snapshot when next event was last computed
* @timer_expires_base: Base time clock monotonic for @timer_expires
* @timer_expires: Anticipated timer expiration time (in case sched tick is stopped)
* @next_timer: Expiry time of next expiring timer for debugging purpose only
* @idle_expires: Next tick in idle, for debugging purpose only
* @idle_calls: Total number of idle calls
* @idle_sleeps: Number of idle calls, where the sched tick was stopped
* @idle_exittime: Time when the idle state was left
* @idle_sleeptime: Sum of the time slept in idle with sched tick stopped
* @iowait_sleeptime: Sum of the time slept in idle with sched tick stopped, with IO outstanding
* @tick_dep_mask: Tick dependency mask - is set, if someone needs the tick
* @check_clocks: Notification mechanism about clocksource changes
*/
struct tick_sched {
/* Common flags */
unsigned long flags;
/* Tick handling: jiffies stall check */
unsigned int stalled_jiffies;
unsigned long last_tick_jiffies;
/* Tick handling */
struct hrtimer sched_timer;
ktime_t last_tick;
ktime_t next_tick;
unsigned long idle_jiffies;
ktime_t idle_waketime;
unsigned int got_idle_tick;
/* Idle entry */
seqcount_t idle_sleeptime_seq;
ktime_t idle_entrytime;
/* Tick stop */
unsigned long last_jiffies;
u64 timer_expires_base;
u64 timer_expires;
u64 next_timer;
ktime_t idle_expires;
unsigned long idle_calls;
unsigned long idle_sleeps;
/* Idle exit */
ktime_t idle_exittime;
ktime_t idle_sleeptime;
ktime_t iowait_sleeptime;
/* Full dynticks handling */
atomic_t tick_dep_mask;
/* Clocksource changes */
unsigned long check_clocks;
};
extern struct tick_sched *tick_get_tick_sched(int cpu);
extern void tick_setup_sched_timer(bool hrtimer);
#if defined CONFIG_TICK_ONESHOT
extern void tick_sched_timer_dying(int cpu);
#else
static inline void tick_sched_timer_dying(int cpu) { }
#endif
#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
extern int __tick_broadcast_oneshot_control(enum tick_broadcast_state state);
#else
static inline int
__tick_broadcast_oneshot_control(enum tick_broadcast_state state)
{
return -EBUSY;
}
#endif
#endif
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