sched.h

Axis 221 camera embedded programing interface

	 * - everyone except group_exit_task is stopped during signal delivery
	 *   of fatal signals, group_exit_task processes the signal.
	 */
	struct task_struct	*group_exit_task;
	int			notify_count;

	/* thread group stop support, overloads group_exit_code too */
	int			group_stop_count;
	unsigned int		flags; /* see SIGNAL_* flags below */

	/* POSIX.1b Interval Timers */
	struct list_head posix_timers;

	/* ITIMER_REAL timer for the process */
	struct hrtimer real_timer;
	struct task_struct *tsk;
	ktime_t it_real_incr;

	/* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
	cputime_t it_prof_expires, it_virt_expires;
	cputime_t it_prof_incr, it_virt_incr;

	/* job control IDs */
	pid_t pgrp;
	pid_t tty_old_pgrp;

	union {
		pid_t session __deprecated;
		pid_t __session;
	};

	/* boolean value for session group leader */
	int leader;

	struct tty_struct *tty; /* NULL if no tty */

	/*
	 * Cumulative resource counters for dead threads in the group,
	 * and for reaped dead child processes forked by this group.
	 * Live threads maintain their own counters and add to these
	 * in __exit_signal, except for the group leader.
	 */
	cputime_t utime, stime, cutime, cstime;
	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;

	/*
	 * Cumulative ns of scheduled CPU time for dead threads in the
	 * group, not including a zombie group leader.  (This only differs
	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
	 * other than jiffies.)
	 */
	unsigned long long sched_time;

	/*
	 * We don't bother to synchronize most readers of this at all,
	 * because there is no reader checking a limit that actually needs
	 * to get both rlim_cur and rlim_max atomically, and either one
	 * alone is a single word that can safely be read normally.
	 * getrlimit/setrlimit use task_lock(current->group_leader) to
	 * protect this instead of the siglock, because they really
	 * have no need to disable irqs.
	 */
	struct rlimit rlim[RLIM_NLIMITS];

	struct list_head cpu_timers[3];

	/* keep the process-shared keyrings here so that they do the right
	 * thing in threads created with CLONE_THREAD */
#ifdef CONFIG_KEYS
	struct key *session_keyring;	/* keyring inherited over fork */
	struct key *process_keyring;	/* keyring private to this process */
#endif
#ifdef CONFIG_BSD_PROCESS_ACCT
	struct pacct_struct pacct;	/* per-process accounting information */
#endif
#ifdef CONFIG_TASKSTATS
	struct taskstats *stats;
#endif
};

/* Context switch must be unlocked if interrupts are to be enabled */
#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
# define __ARCH_WANT_UNLOCKED_CTXSW
#endif

/*
 * Bits in flags field of signal_struct.
 */
#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
#define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
#define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
#define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */


/*
 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
 * values are inverted: lower p->prio value means higher priority.
 *
 * The MAX_USER_RT_PRIO value allows the actual maximum
 * RT priority to be separate from the value exported to
 * user-space.  This allows kernel threads to set their
 * priority to a value higher than any user task. Note:
 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
 */

#define MAX_USER_RT_PRIO	100
#define MAX_RT_PRIO		MAX_USER_RT_PRIO

#define MAX_PRIO		(MAX_RT_PRIO + 40)

#define rt_prio(prio)		unlikely((prio) < MAX_RT_PRIO)
#define rt_task(p)		rt_prio((p)->prio)
#define batch_task(p)		(unlikely((p)->policy == SCHED_BATCH))
#define is_rt_policy(p)		((p) != SCHED_NORMAL && (p) != SCHED_BATCH)
#define has_rt_policy(p)	unlikely(is_rt_policy((p)->policy))

/*
 * Some day this will be a full-fledged user tracking system..
 */
struct user_struct {
	atomic_t __count;	/* reference count */
	atomic_t processes;	/* How many processes does this user have? */
	atomic_t files;		/* How many open files does this user have? */
	atomic_t sigpending;	/* How many pending signals does this user have? */
#ifdef CONFIG_INOTIFY_USER
	atomic_t inotify_watches; /* How many inotify watches does this user have? */
	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
#endif
	/* protected by mq_lock	*/
	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
	unsigned long locked_shm; /* How many pages of mlocked shm ? */

#ifdef CONFIG_KEYS
	struct key *uid_keyring;	/* UID specific keyring */
	struct key *session_keyring;	/* UID's default session keyring */
#endif

	/* Hash table maintenance information */
	struct list_head uidhash_list;
	uid_t uid;
};

extern struct user_struct *find_user(uid_t);

extern struct user_struct root_user;
#define INIT_USER (&root_user)

struct backing_dev_info;
struct reclaim_state;

#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
struct sched_info {
	/* cumulative counters */
	unsigned long	cpu_time,	/* time spent on the cpu */
			run_delay,	/* time spent waiting on a runqueue */
			pcnt;		/* # of timeslices run on this cpu */

	/* timestamps */
	unsigned long	last_arrival,	/* when we last ran on a cpu */
			last_queued;	/* when we were last queued to run */
};
#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */

#ifdef CONFIG_SCHEDSTATS
extern const struct file_operations proc_schedstat_operations;
#endif /* CONFIG_SCHEDSTATS */

#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info {
	spinlock_t	lock;
	unsigned int	flags;	/* Private per-task flags */

	/* For each stat XXX, add following, aligned appropriately
	 *
	 * struct timespec XXX_start, XXX_end;
	 * u64 XXX_delay;
	 * u32 XXX_count;
	 *
	 * Atomicity of updates to XXX_delay, XXX_count protected by
	 * single lock above (split into XXX_lock if contention is an issue).
	 */

	/*
	 * XXX_count is incremented on every XXX operation, the delay
	 * associated with the operation is added to XXX_delay.
	 * XXX_delay contains the accumulated delay time in nanoseconds.
	 */
	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
	u64 blkio_delay;	/* wait for sync block io completion */
	u64 swapin_delay;	/* wait for swapin block io completion */
	u32 blkio_count;	/* total count of the number of sync block */
				/* io operations performed */
	u32 swapin_count;	/* total count of the number of swapin block */
				/* io operations performed */
};
#endif	/* CONFIG_TASK_DELAY_ACCT */

static inline int sched_info_on(void)
{
#ifdef CONFIG_SCHEDSTATS
	return 1;
#elif defined(CONFIG_TASK_DELAY_ACCT)
	extern int delayacct_on;
	return delayacct_on;
#else
	return 0;
#endif
}

enum idle_type
{
	SCHED_IDLE,
	NOT_IDLE,
	NEWLY_IDLE,
	MAX_IDLE_TYPES
};

/*
 * sched-domains (multiprocessor balancing) declarations:
 */
#define SCHED_LOAD_SCALE	128UL	/* increase resolution of load */

#ifdef CONFIG_SMP
#define SD_LOAD_BALANCE		1	/* Do load balancing on this domain. */
#define SD_BALANCE_NEWIDLE	2	/* Balance when about to become idle */
#define SD_BALANCE_EXEC		4	/* Balance on exec */
#define SD_BALANCE_FORK		8	/* Balance on fork, clone */
#define SD_WAKE_IDLE		16	/* Wake to idle CPU on task wakeup */
#define SD_WAKE_AFFINE		32	/* Wake task to waking CPU */
#define SD_WAKE_BALANCE		64	/* Perform balancing at task wakeup */
#define SD_SHARE_CPUPOWER	128	/* Domain members share cpu power */
#define SD_POWERSAVINGS_BALANCE	256	/* Balance for power savings */
#define SD_SHARE_PKG_RESOURCES	512	/* Domain members share cpu pkg resources */
#define SD_SERIALIZE		1024	/* Only a single load balancing instance */

#define BALANCE_FOR_MC_POWER	\
	(sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)

#define BALANCE_FOR_PKG_POWER	\
	((sched_mc_power_savings || sched_smt_power_savings) ?	\
	 SD_POWERSAVINGS_BALANCE : 0)

#define test_sd_parent(sd, flag)	((sd->parent &&		\
					 (sd->parent->flags & flag)) ? 1 : 0)


struct sched_group {
	struct sched_group *next;	/* Must be a circular list */
	cpumask_t cpumask;

	/*
	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
	 * single CPU. This is read only (except for setup, hotplug CPU).
	 */
	unsigned long cpu_power;
};

struct sched_domain {
	/* These fields must be setup */
	struct sched_domain *parent;	/* top domain must be null terminated */
	struct sched_domain *child;	/* bottom domain must be null terminated */
	struct sched_group *groups;	/* the balancing groups of the domain */
	cpumask_t span;			/* span of all CPUs in this domain */
	unsigned long min_interval;	/* Minimum balance interval ms */
	unsigned long max_interval;	/* Maximum balance interval ms */
	unsigned int busy_factor;	/* less balancing by factor if busy */
	unsigned int imbalance_pct;	/* No balance until over watermark */
	unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
	unsigned int per_cpu_gain;	/* CPU % gained by adding domain cpus */
	unsigned int busy_idx;
	unsigned int idle_idx;
	unsigned int newidle_idx;
	unsigned int wake_idx;
	unsigned int forkexec_idx;
	int flags;			/* See SD_* */

	/* Runtime fields. */
	unsigned long last_balance;	/* init to jiffies. units in jiffies */
	unsigned int balance_interval;	/* initialise to 1. units in ms. */
	unsigned int nr_balance_failed; /* initialise to 0 */

#ifdef CONFIG_SCHEDSTATS
	/* load_balance() stats */
	unsigned long lb_cnt[MAX_IDLE_TYPES];
	unsigned long lb_failed[MAX_IDLE_TYPES];
	unsigned long lb_balanced[MAX_IDLE_TYPES];
	unsigned long lb_imbalance[MAX_IDLE_TYPES];
	unsigned long lb_gained[MAX_IDLE_TYPES];
	unsigned long lb_hot_gained[MAX_IDLE_TYPES];
	unsigned long lb_nobusyg[MAX_IDLE_TYPES];
	unsigned long lb_nobusyq[MAX_IDLE_TYPES];

	/* Active load balancing */
	unsigned long alb_cnt;
	unsigned long alb_failed;
	unsigned long alb_pushed;

	/* SD_BALANCE_EXEC stats */
	unsigned long sbe_cnt;
	unsigned long sbe_balanced;
	unsigned long sbe_pushed;

	/* SD_BALANCE_FORK stats */
	unsigned long sbf_cnt;
	unsigned long sbf_balanced;
	unsigned long sbf_pushed;

	/* try_to_wake_up() stats */
	unsigned long ttwu_wake_remote;
	unsigned long ttwu_move_affine;
	unsigned long ttwu_move_balance;
#endif
};

extern int partition_sched_domains(cpumask_t *partition1,
				    cpumask_t *partition2);

/*
 * Maximum cache size the migration-costs auto-tuning code will
 * search from:
 */
extern unsigned int max_cache_size;

#endif	/* CONFIG_SMP */


struct io_context;			/* See blkdev.h */
struct cpuset;

#define NGROUPS_SMALL		32
#define NGROUPS_PER_BLOCK	((int)(PAGE_SIZE / sizeof(gid_t)))
struct group_info {
	int ngroups;
	atomic_t usage;
	gid_t small_block[NGROUPS_SMALL];
	int nblocks;
	gid_t *blocks[0];
};

/*
 * get_group_info() must be called with the owning task locked (via task_lock())
 * when task != current.  The reason being that the vast majority of callers are
 * looking at current->group_info, which can not be changed except by the
 * current task.  Changing current->group_info requires the task lock, too.
 */
#define get_group_info(group_info) do { \
	atomic_inc(&(group_info)->usage); \
} while (0)

#define put_group_info(group_info) do { \
	if (atomic_dec_and_test(&(group_info)->usage)) \
		groups_free(group_info); \
} while (0)

extern struct group_info *groups_alloc(int gidsetsize);
extern void groups_free(struct group_info *group_info);
extern int set_current_groups(struct group_info *group_info);
extern int groups_search(struct group_info *group_info, gid_t grp);
/* access the groups "array" with this macro */
#define GROUP_AT(gi, i) \
    ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])

#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
extern void prefetch_stack(struct task_struct *t);
#else
static inline void prefetch_stack(struct task_struct *t) { }
#endif

struct audit_context;		/* See audit.c */
struct mempolicy;
struct pipe_inode_info;
struct uts_namespace;

enum sleep_type {
	SLEEP_NORMAL,
	SLEEP_NONINTERACTIVE,
	SLEEP_INTERACTIVE,
	SLEEP_INTERRUPTED,
};

struct prio_array;

struct task_struct {
	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
	struct thread_info *thread_info;
	atomic_t usage;
	unsigned long flags;	/* per process flags, defined below */
	unsigned long ptrace;

	int lock_depth;		/* BKL lock depth */

#ifdef CONFIG_SMP
#ifdef __ARCH_WANT_UNLOCKED_CTXSW
	int oncpu;
#endif
#endif
	int load_weight;	/* for niceness load balancing purposes */
	int prio, static_prio, normal_prio;
	struct list_head run_list;
	struct prio_array *array;

	unsigned short ioprio;
#ifdef CONFIG_BLK_DEV_IO_TRACE
	unsigned int btrace_seq;
#endif
	unsigned long sleep_avg;
	unsigned long long timestamp, last_ran;
	unsigned long long sched_time; /* sched_clock time spent running */
	enum sleep_type sleep_type;