kernel-ark/include/linux/tick.h
Thomas Gleixner 5df7fa1c62 tick-sched: add more debug information
To allow better diagnosis of tick-sched related, especially NOHZ
related problems, we need to know when the last wakeup via an irq
happened and when the CPU left the idle state.

Add two fields (idle_waketime, idle_exittime) to the tick_sched
structure and add them to the timer_list output.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-01 17:45:14 +01:00

129 lines
3.9 KiB
C

/* linux/include/linux/tick.h
*
* This file contains the structure definitions for tick related functions
*
*/
#ifndef _LINUX_TICK_H
#define _LINUX_TICK_H
#include <linux/clockchips.h>
#ifdef CONFIG_GENERIC_CLOCKEVENTS
enum tick_device_mode {
TICKDEV_MODE_PERIODIC,
TICKDEV_MODE_ONESHOT,
};
struct tick_device {
struct clock_event_device *evtdev;
enum tick_device_mode mode;
};
enum tick_nohz_mode {
NOHZ_MODE_INACTIVE,
NOHZ_MODE_LOWRES,
NOHZ_MODE_HIGHRES,
};
/**
* struct tick_sched - sched tick emulation and no idle tick control/stats
* @sched_timer: hrtimer to schedule the periodic tick in high
* resolution mode
* @idle_tick: Store the last idle tick expiry time when the tick
* timer is modified for idle sleeps. This is necessary
* to resume the tick timer operation in the timeline
* when the CPU returns from idle
* @tick_stopped: Indicator that the idle tick has been stopped
* @idle_jiffies: jiffies at the entry to idle for idle time accounting
* @idle_calls: Total number of idle calls
* @idle_sleeps: Number of idle calls, where the sched tick was stopped
* @idle_entrytime: Time when the idle call was entered
* @idle_waketime: Time when the idle was interrupted
* @idle_exittime: Time when the idle state was left
* @idle_sleeptime: Sum of the time slept in idle with sched tick stopped
* @sleep_length: Duration of the current idle sleep
*/
struct tick_sched {
struct hrtimer sched_timer;
unsigned long check_clocks;
enum tick_nohz_mode nohz_mode;
ktime_t idle_tick;
int tick_stopped;
unsigned long idle_jiffies;
unsigned long idle_calls;
unsigned long idle_sleeps;
int idle_active;
ktime_t idle_entrytime;
ktime_t idle_waketime;
ktime_t idle_exittime;
ktime_t idle_sleeptime;
ktime_t idle_lastupdate;
ktime_t sleep_length;
unsigned long last_jiffies;
unsigned long next_jiffies;
ktime_t idle_expires;
};
extern void __init tick_init(void);
extern int tick_is_oneshot_available(void);
extern struct tick_device *tick_get_device(int cpu);
# ifdef CONFIG_HIGH_RES_TIMERS
extern int tick_init_highres(void);
extern int tick_program_event(ktime_t expires, int force);
extern void tick_setup_sched_timer(void);
extern void tick_cancel_sched_timer(int cpu);
# else
static inline void tick_cancel_sched_timer(int cpu) { }
# endif /* HIGHRES */
# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
extern struct tick_device *tick_get_broadcast_device(void);
extern cpumask_t *tick_get_broadcast_mask(void);
# ifdef CONFIG_TICK_ONESHOT
extern cpumask_t *tick_get_broadcast_oneshot_mask(void);
# endif
# endif /* BROADCAST */
# ifdef CONFIG_TICK_ONESHOT
extern void tick_clock_notify(void);
extern int tick_check_oneshot_change(int allow_nohz);
extern struct tick_sched *tick_get_tick_sched(int cpu);
# else
static inline void tick_clock_notify(void) { }
static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
# endif
#else /* CONFIG_GENERIC_CLOCKEVENTS */
static inline void tick_init(void) { }
static inline void tick_cancel_sched_timer(int cpu) { }
static inline void tick_clock_notify(void) { }
static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
# ifdef CONFIG_NO_HZ
extern void tick_nohz_stop_sched_tick(void);
extern void tick_nohz_restart_sched_tick(void);
extern void tick_nohz_update_jiffies(void);
extern ktime_t tick_nohz_get_sleep_length(void);
extern void tick_nohz_stop_idle(int cpu);
extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
# else
static inline void tick_nohz_stop_sched_tick(void) { }
static inline void tick_nohz_restart_sched_tick(void) { }
static inline void tick_nohz_update_jiffies(void) { }
static inline ktime_t tick_nohz_get_sleep_length(void)
{
ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
return len;
}
static inline void tick_nohz_stop_idle(int cpu) { }
static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return 0; }
# endif /* !NO_HZ */
#endif