timers/nohz: Restructure and reshuffle struct tick_sched

/**

 * struct tick_sched - sched tick emulation and no idle tick control/stats

 * @sched_timer:	hrtimer to schedule the periodic tick in high

 *			resolution mode

 * @check_clocks:	Notification mechanism about clocksource changes

 * @nohz_mode:		Mode - one state of tick_nohz_mode

 *

 * @inidle:		Indicator that the CPU is in the tick idle mode

 * @tick_stopped:	Indicator that the idle tick has been stopped

 * @idle_active:	Indicator that the CPU is actively in the tick idle mode;

 *			it is reset during irq handling phases.

 * @do_timer_lst:	CPU was the last one doing do_timer before going idle

 * @do_timer_last:	CPU was the last one doing do_timer before going idle

 * @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_entrytime:	Time when the idle call was entered

 * @nohz_mode:		Mode - one state of tick_nohz_mode

 * @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_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

 * @iowait_sleeptime:	Sum of the time slept in idle with sched tick stopped, with IO outstanding

 * @timer_expires:	Anticipated timer expiration time (in case sched tick is stopped)

 * @timer_expires_base:	Base time clock monotonic for @timer_expires

 * @next_timer:		Expiry time of next expiring timer for debugging purpose only

 * @tick_dep_mask:	Tick dependency mask - is set, if someone needs the tick

 * @last_tick_jiffies:	Value of jiffies seen on last tick

 * @stalled_jiffies:	Number of stalled jiffies detected across ticks

 * @check_clocks:	Notification mechanism about clocksource changes

 */

struct tick_sched {

	struct hrtimer			sched_timer;

	unsigned long			check_clocks;

	enum tick_nohz_mode		nohz_mode;

	/* Common flags */

	unsigned int			inidle		: 1;

	unsigned int			tick_stopped	: 1;

	unsigned int			idle_active	: 1;

	unsigned int			do_timer_last	: 1;

	unsigned int			got_idle_tick	: 1;

	/* 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;

	unsigned long			idle_calls;

	unsigned long			idle_sleeps;

	ktime_t				idle_entrytime;

	ktime_t				idle_waketime;

	ktime_t				idle_exittime;

	ktime_t				idle_sleeptime;

	ktime_t				iowait_sleeptime;

	/* Idle entry */

	ktime_t				idle_entrytime;

	/* Tick stop */

	enum tick_nohz_mode		nohz_mode;

	unsigned long			last_jiffies;

	u64				timer_expires;

	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;

	unsigned long			last_tick_jiffies;

	unsigned int			stalled_jiffies;

	/* Clocksource changes */

	unsigned long			check_clocks;

};

extern struct tick_sched *tick_get_tick_sched(int cpu);