sched.h 73.6 KB
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#ifndef _LINUX_SCHED_H
#define _LINUX_SCHED_H

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/*
 * cloning flags:
 */
#define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
#define CLONE_VM	0x00000100	/* set if VM shared between processes */
#define CLONE_FS	0x00000200	/* set if fs info shared between processes */
#define CLONE_FILES	0x00000400	/* set if open files shared between processes */
#define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
#define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
#define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
#define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
#define CLONE_THREAD	0x00010000	/* Same thread group? */
#define CLONE_NEWNS	0x00020000	/* New namespace group? */
#define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
#define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
#define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
#define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
#define CLONE_DETACHED		0x00400000	/* Unused, ignored */
#define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
#define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
#define CLONE_STOPPED		0x02000000	/* Start in stopped state */
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#define CLONE_NEWUTS		0x04000000	/* New utsname group? */
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#define CLONE_NEWIPC		0x08000000	/* New ipcs */
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#define CLONE_NEWUSER		0x10000000	/* New user namespace */
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#define CLONE_NEWPID		0x20000000	/* New pid namespace */
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#define CLONE_NEWNET		0x40000000	/* New network namespace */
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#define CLONE_IO		0x80000000	/* Clone io context */
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/*
 * Scheduling policies
 */
#define SCHED_NORMAL		0
#define SCHED_FIFO		1
#define SCHED_RR		2
#define SCHED_BATCH		3
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/* SCHED_ISO: reserved but not implemented yet */
#define SCHED_IDLE		5
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/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
#define SCHED_RESET_ON_FORK     0x40000000
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#ifdef __KERNEL__
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struct sched_param {
	int sched_priority;
};

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#include <asm/param.h>	/* for HZ */

#include <linux/capability.h>
#include <linux/threads.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/timex.h>
#include <linux/jiffies.h>
#include <linux/rbtree.h>
#include <linux/thread_info.h>
#include <linux/cpumask.h>
#include <linux/errno.h>
#include <linux/nodemask.h>
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#include <linux/mm_types.h>
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#include <asm/system.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/cputime.h>

#include <linux/smp.h>
#include <linux/sem.h>
#include <linux/signal.h>
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#include <linux/path.h>
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#include <linux/compiler.h>
#include <linux/completion.h>
#include <linux/pid.h>
#include <linux/percpu.h>
#include <linux/topology.h>
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#include <linux/proportions.h>
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#include <linux/seccomp.h>
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#include <linux/rcupdate.h>
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#include <linux/rculist.h>
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#include <linux/rtmutex.h>
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#include <linux/time.h>
#include <linux/param.h>
#include <linux/resource.h>
#include <linux/timer.h>
#include <linux/hrtimer.h>
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#include <linux/task_io_accounting.h>
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#include <linux/kobject.h>
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#include <linux/latencytop.h>
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#include <linux/cred.h>
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#include <asm/processor.h>
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struct exec_domain;
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struct futex_pi_state;
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struct robust_list_head;
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struct bio_list;
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struct fs_struct;
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struct perf_event_context;
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/*
 * List of flags we want to share for kernel threads,
 * if only because they are not used by them anyway.
 */
#define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)

/*
 * These are the constant used to fake the fixed-point load-average
 * counting. Some notes:
 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 *    a load-average precision of 10 bits integer + 11 bits fractional
 *  - if you want to count load-averages more often, you need more
 *    precision, or rounding will get you. With 2-second counting freq,
 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 *    11 bit fractions.
 */
extern unsigned long avenrun[];		/* Load averages */
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extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
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#define FSHIFT		11		/* nr of bits of precision */
#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
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#define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
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#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
#define EXP_5		2014		/* 1/exp(5sec/5min) */
#define EXP_15		2037		/* 1/exp(5sec/15min) */

#define CALC_LOAD(load,exp,n) \
	load *= exp; \
	load += n*(FIXED_1-exp); \
	load >>= FSHIFT;

extern unsigned long total_forks;
extern int nr_threads;
DECLARE_PER_CPU(unsigned long, process_counts);
extern int nr_processes(void);
extern unsigned long nr_running(void);
extern unsigned long nr_uninterruptible(void);
extern unsigned long nr_iowait(void);
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extern unsigned long nr_iowait_cpu(void);
extern unsigned long this_cpu_load(void);


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extern void calc_global_load(void);
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extern unsigned long get_parent_ip(unsigned long addr);

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struct seq_file;
struct cfs_rq;
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struct task_group;
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#ifdef CONFIG_SCHED_DEBUG
extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
extern void proc_sched_set_task(struct task_struct *p);
extern void
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print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
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#else
static inline void
proc_sched_show_task(struct task_struct *p, struct seq_file *m)
{
}
static inline void proc_sched_set_task(struct task_struct *p)
{
}
static inline void
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print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
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{
}
#endif
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/*
 * Task state bitmask. NOTE! These bits are also
 * encoded in fs/proc/array.c: get_task_state().
 *
 * We have two separate sets of flags: task->state
 * is about runnability, while task->exit_state are
 * about the task exiting. Confusing, but this way
 * modifying one set can't modify the other one by
 * mistake.
 */
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#define TASK_RUNNING		0
#define TASK_INTERRUPTIBLE	1
#define TASK_UNINTERRUPTIBLE	2
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#define __TASK_STOPPED		4
#define __TASK_TRACED		8
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/* in tsk->exit_state */
#define EXIT_ZOMBIE		16
#define EXIT_DEAD		32
/* in tsk->state again */
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#define TASK_DEAD		64
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#define TASK_WAKEKILL		128
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#define TASK_WAKING		256
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#define TASK_STATE_MAX		512
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#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
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extern char ___assert_task_state[1 - 2*!!(
		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
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/* Convenience macros for the sake of set_task_state */
#define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
#define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
#define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
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/* Convenience macros for the sake of wake_up */
#define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
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#define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
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/* get_task_state() */
#define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
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				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
				 __TASK_TRACED)
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#define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
#define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
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#define task_is_stopped_or_traced(task)	\
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			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
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#define task_contributes_to_load(task)	\
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				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
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				 (task->flags & PF_FREEZING) == 0)
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#define __set_task_state(tsk, state_value)		\
	do { (tsk)->state = (state_value); } while (0)
#define set_task_state(tsk, state_value)		\
	set_mb((tsk)->state, (state_value))

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/*
 * set_current_state() includes a barrier so that the write of current->state
 * is correctly serialised wrt the caller's subsequent test of whether to
 * actually sleep:
 *
 *	set_current_state(TASK_UNINTERRUPTIBLE);
 *	if (do_i_need_to_sleep())
 *		schedule();
 *
 * If the caller does not need such serialisation then use __set_current_state()
 */
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#define __set_current_state(state_value)			\
	do { current->state = (state_value); } while (0)
#define set_current_state(state_value)		\
	set_mb(current->state, (state_value))

/* Task command name length */
#define TASK_COMM_LEN 16

#include <linux/spinlock.h>

/*
 * This serializes "schedule()" and also protects
 * the run-queue from deletions/modifications (but
 * _adding_ to the beginning of the run-queue has
 * a separate lock).
 */
extern rwlock_t tasklist_lock;
extern spinlock_t mmlist_lock;

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struct task_struct;
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#ifdef CONFIG_PROVE_RCU
extern int lockdep_tasklist_lock_is_held(void);
#endif /* #ifdef CONFIG_PROVE_RCU */

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extern void sched_init(void);
extern void sched_init_smp(void);
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extern asmlinkage void schedule_tail(struct task_struct *prev);
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extern void init_idle(struct task_struct *idle, int cpu);
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extern void init_idle_bootup_task(struct task_struct *idle);
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extern int runqueue_is_locked(int cpu);
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extern cpumask_var_t nohz_cpu_mask;
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#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
extern int select_nohz_load_balancer(int cpu);
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extern int get_nohz_load_balancer(void);
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extern int nohz_ratelimit(int cpu);
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#else
static inline int select_nohz_load_balancer(int cpu)
{
	return 0;
}
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static inline int nohz_ratelimit(int cpu)
{
	return 0;
}
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#endif
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/*
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 * Only dump TASK_* tasks. (0 for all tasks)
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 */
extern void show_state_filter(unsigned long state_filter);

static inline void show_state(void)
{
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	show_state_filter(0);
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}

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extern void show_regs(struct pt_regs *);

/*
 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 * task), SP is the stack pointer of the first frame that should be shown in the back
 * trace (or NULL if the entire call-chain of the task should be shown).
 */
extern void show_stack(struct task_struct *task, unsigned long *sp);

void io_schedule(void);
long io_schedule_timeout(long timeout);

extern void cpu_init (void);
extern void trap_init(void);
extern void update_process_times(int user);
extern void scheduler_tick(void);

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extern void sched_show_task(struct task_struct *p);

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#ifdef CONFIG_DETECT_SOFTLOCKUP
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extern void softlockup_tick(void);
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extern void touch_softlockup_watchdog(void);
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extern void touch_softlockup_watchdog_sync(void);
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extern void touch_all_softlockup_watchdogs(void);
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extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
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				    void __user *buffer,
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				    size_t *lenp, loff_t *ppos);
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extern unsigned int  softlockup_panic;
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extern int softlockup_thresh;
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#else
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static inline void softlockup_tick(void)
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{
}
static inline void touch_softlockup_watchdog(void)
{
}
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static inline void touch_softlockup_watchdog_sync(void)
{
}
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static inline void touch_all_softlockup_watchdogs(void)
{
}
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#endif

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#ifdef CONFIG_DETECT_HUNG_TASK
extern unsigned int  sysctl_hung_task_panic;
extern unsigned long sysctl_hung_task_check_count;
extern unsigned long sysctl_hung_task_timeout_secs;
extern unsigned long sysctl_hung_task_warnings;
extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
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					 void __user *buffer,
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					 size_t *lenp, loff_t *ppos);
#endif
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/* Attach to any functions which should be ignored in wchan output. */
#define __sched		__attribute__((__section__(".sched.text")))
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/* Linker adds these: start and end of __sched functions */
extern char __sched_text_start[], __sched_text_end[];

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/* Is this address in the __sched functions? */
extern int in_sched_functions(unsigned long addr);

#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
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extern signed long schedule_timeout(signed long timeout);
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extern signed long schedule_timeout_interruptible(signed long timeout);
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extern signed long schedule_timeout_killable(signed long timeout);
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extern signed long schedule_timeout_uninterruptible(signed long timeout);
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asmlinkage void schedule(void);
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extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
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struct nsproxy;
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struct user_namespace;
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/*
 * Default maximum number of active map areas, this limits the number of vmas
 * per mm struct. Users can overwrite this number by sysctl but there is a
 * problem.
 *
 * When a program's coredump is generated as ELF format, a section is created
 * per a vma. In ELF, the number of sections is represented in unsigned short.
 * This means the number of sections should be smaller than 65535 at coredump.
 * Because the kernel adds some informative sections to a image of program at
 * generating coredump, we need some margin. The number of extra sections is
 * 1-3 now and depends on arch. We use "5" as safe margin, here.
 */
#define MAPCOUNT_ELF_CORE_MARGIN	(5)
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#define DEFAULT_MAX_MAP_COUNT	(USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
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extern int sysctl_max_map_count;

#include <linux/aio.h>

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#ifdef CONFIG_MMU
extern void arch_pick_mmap_layout(struct mm_struct *mm);
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extern unsigned long
arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
		       unsigned long, unsigned long);
extern unsigned long
arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
			  unsigned long len, unsigned long pgoff,
			  unsigned long flags);
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extern void arch_unmap_area(struct mm_struct *, unsigned long);
extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
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#else
static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
#endif
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extern void set_dumpable(struct mm_struct *mm, int value);
extern int get_dumpable(struct mm_struct *mm);

/* mm flags */
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/* dumpable bits */
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#define MMF_DUMPABLE      0  /* core dump is permitted */
#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
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#define MMF_DUMPABLE_BITS 2
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#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
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/* coredump filter bits */
#define MMF_DUMP_ANON_PRIVATE	2
#define MMF_DUMP_ANON_SHARED	3
#define MMF_DUMP_MAPPED_PRIVATE	4
#define MMF_DUMP_MAPPED_SHARED	5
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#define MMF_DUMP_ELF_HEADERS	6
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#define MMF_DUMP_HUGETLB_PRIVATE 7
#define MMF_DUMP_HUGETLB_SHARED  8
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#define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
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#define MMF_DUMP_FILTER_BITS	7
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#define MMF_DUMP_FILTER_MASK \
	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
#define MMF_DUMP_FILTER_DEFAULT \
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	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
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	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)

#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
# define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
#else
# define MMF_DUMP_MASK_DEFAULT_ELF	0
#endif
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					/* leave room for more dump flags */
#define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */

#define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
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struct sighand_struct {
	atomic_t		count;
	struct k_sigaction	action[_NSIG];
	spinlock_t		siglock;
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	wait_queue_head_t	signalfd_wqh;
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};

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struct pacct_struct {
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	int			ac_flag;
	long			ac_exitcode;
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	unsigned long		ac_mem;
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	cputime_t		ac_utime, ac_stime;
	unsigned long		ac_minflt, ac_majflt;
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};

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struct cpu_itimer {
	cputime_t expires;
	cputime_t incr;
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	u32 error;
	u32 incr_error;
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};

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/**
 * struct task_cputime - collected CPU time counts
 * @utime:		time spent in user mode, in &cputime_t units
 * @stime:		time spent in kernel mode, in &cputime_t units
 * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
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 *
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 * This structure groups together three kinds of CPU time that are
 * tracked for threads and thread groups.  Most things considering
 * CPU time want to group these counts together and treat all three
 * of them in parallel.
 */
struct task_cputime {
	cputime_t utime;
	cputime_t stime;
	unsigned long long sum_exec_runtime;
};
/* Alternate field names when used to cache expirations. */
#define prof_exp	stime
#define virt_exp	utime
#define sched_exp	sum_exec_runtime

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#define INIT_CPUTIME	\
	(struct task_cputime) {					\
		.utime = cputime_zero,				\
		.stime = cputime_zero,				\
		.sum_exec_runtime = 0,				\
	}

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/*
 * Disable preemption until the scheduler is running.
 * Reset by start_kernel()->sched_init()->init_idle().
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 *
 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
 * before the scheduler is active -- see should_resched().
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 */
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#define INIT_PREEMPT_COUNT	(1 + PREEMPT_ACTIVE)
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/**
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 * struct thread_group_cputimer - thread group interval timer counts
 * @cputime:		thread group interval timers.
 * @running:		non-zero when there are timers running and
 * 			@cputime receives updates.
 * @lock:		lock for fields in this struct.
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 *
 * This structure contains the version of task_cputime, above, that is
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 * used for thread group CPU timer calculations.
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 */
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struct thread_group_cputimer {
	struct task_cputime cputime;
	int running;
	spinlock_t lock;
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};

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/*
 * NOTE! "signal_struct" does not have it's own
 * locking, because a shared signal_struct always
 * implies a shared sighand_struct, so locking
 * sighand_struct is always a proper superset of
 * the locking of signal_struct.
 */
struct signal_struct {
529
	atomic_t		sigcnt;
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	atomic_t		live;
531
	int			nr_threads;
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	wait_queue_head_t	wait_chldexit;	/* for wait4() */

	/* current thread group signal load-balancing target: */
536
	struct task_struct	*curr_target;
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	/* shared signal handling: */
	struct sigpending	shared_pending;

	/* thread group exit support */
	int			group_exit_code;
	/* overloaded:
	 * - notify group_exit_task when ->count is equal to notify_count
	 * - everyone except group_exit_task is stopped during signal delivery
	 *   of fatal signals, group_exit_task processes the signal.
	 */
	int			notify_count;
549
	struct task_struct	*group_exit_task;
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	/* 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 */
559
	struct hrtimer real_timer;
560
	struct pid *leader_pid;
561
	ktime_t it_real_incr;
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	/*
	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
	 * values are defined to 0 and 1 respectively
	 */
	struct cpu_itimer it[2];
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570
	/*
571 572
	 * Thread group totals for process CPU timers.
	 * See thread_group_cputimer(), et al, for details.
573
	 */
574
	struct thread_group_cputimer cputimer;
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	/* Earliest-expiration cache. */
	struct task_cputime cputime_expires;

	struct list_head cpu_timers[3];

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	struct pid *tty_old_pgrp;
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	/* 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.
	 */
594
	cputime_t utime, stime, cutime, cstime;
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	cputime_t gtime;
	cputime_t cgtime;
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#ifndef CONFIG_VIRT_CPU_ACCOUNTING
	cputime_t prev_utime, prev_stime;
#endif
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	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
602
	unsigned long inblock, oublock, cinblock, coublock;
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	unsigned long maxrss, cmaxrss;
604
	struct task_io_accounting ioac;
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	/*
	 * Cumulative ns of schedule CPU time fo 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 sum_sched_runtime;

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	/*
	 * 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];

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#ifdef CONFIG_BSD_PROCESS_ACCT
	struct pacct_struct pacct;	/* per-process accounting information */
#endif
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#ifdef CONFIG_TASKSTATS
	struct taskstats *stats;
#endif
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#ifdef CONFIG_AUDIT
	unsigned audit_tty;
	struct tty_audit_buf *tty_audit_buf;
#endif
635 636

	int oom_adj;	/* OOM kill score adjustment (bit shift) */
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};

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

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/*
 * 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 */
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/*
 * Pending notifications to parent.
 */
#define SIGNAL_CLD_STOPPED	0x00000010
#define SIGNAL_CLD_CONTINUED	0x00000020
#define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
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658 659
#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */

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/* If true, all threads except ->group_exit_task have pending SIGKILL */
static inline int signal_group_exit(const struct signal_struct *sig)
{
	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
		(sig->group_exit_task != NULL);
}

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/*
 * 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? */
675
#ifdef CONFIG_INOTIFY_USER
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	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
679 680 681
#ifdef CONFIG_EPOLL
	atomic_t epoll_watches;	/* The number of file descriptors currently watched */
#endif
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#ifdef CONFIG_POSIX_MQUEUE
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	/* protected by mq_lock	*/
	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
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#endif
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	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 */
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	struct hlist_node uidhash_node;
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	uid_t uid;
696
	struct user_namespace *user_ns;
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698
#ifdef CONFIG_PERF_EVENTS
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	atomic_long_t locked_vm;
#endif
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};

703
extern int uids_sysfs_init(void);
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extern struct user_struct *find_user(uid_t);

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

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struct backing_dev_info;
struct reclaim_state;

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#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
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struct sched_info {
	/* cumulative counters */
717
	unsigned long pcount;	      /* # of times run on this cpu */
718
	unsigned long long run_delay; /* time spent waiting on a runqueue */
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	/* timestamps */
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	unsigned long long last_arrival,/* when we last ran on a cpu */
			   last_queued;	/* when we were last queued to run */
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#ifdef CONFIG_SCHEDSTATS
	/* BKL stats */
725
	unsigned int bkl_count;
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#endif
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};
728
#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
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#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).
	 */
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	/*
	 * 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 */
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	struct timespec freepages_start, freepages_end;
	u64 freepages_delay;	/* wait for memory reclaim */
	u32 freepages_count;	/* total count of memory reclaim */
761
};
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#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;
773
#endif
774
}
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enum cpu_idle_type {
	CPU_IDLE,
	CPU_NOT_IDLE,
	CPU_NEWLY_IDLE,
	CPU_MAX_IDLE_TYPES
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};

/*
 * sched-domains (multiprocessor balancing) declarations:
 */
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/*
 * Increase resolution of nice-level calculations:
 */
#define SCHED_LOAD_SHIFT	10
#define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)

793
#define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
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795
#ifdef CONFIG_SMP
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#define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
#define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
#define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
#define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
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#define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
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#define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
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#define SD_PREFER_LOCAL		0x0040  /* Prefer to keep tasks local to this domain */
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#define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
#define SD_POWERSAVINGS_BALANCE	0x0100	/* Balance for power savings */
#define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
#define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
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#define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
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enum powersavings_balance_level {
	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
					 * first for long running threads
					 */
	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
					 * cpu package for power savings
					 */
	MAX_POWERSAVINGS_BALANCE_LEVELS
};
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821
extern int sched_mc_power_savings, sched_smt_power_savings;
822

823 824 825 826
static inline int sd_balance_for_mc_power(void)
{
	if (sched_smt_power_savings)
		return SD_POWERSAVINGS_BALANCE;
827

828 829 830 831
	if (!sched_mc_power_savings)
		return SD_PREFER_SIBLING;

	return 0;
832
}
833

834 835 836 837 838
static inline int sd_balance_for_package_power(void)
{
	if (sched_mc_power_savings | sched_smt_power_savings)
		return SD_POWERSAVINGS_BALANCE;

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	return SD_PREFER_SIBLING;
840
}
841

842 843 844 845 846 847 848 849 850 851 852 853 854
/*
 * Optimise SD flags for power savings:
 * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
 * Keep default SD flags if sched_{smt,mc}_power_saving=0
 */

static inline int sd_power_saving_flags(void)
{
	if (sched_mc_power_savings | sched_smt_power_savings)
		return SD_BALANCE_NEWIDLE;

	return 0;
}
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struct sched_group {
	struct sched_group *next;	/* Must be a circular list */

	/*
	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
861
	 * single CPU.
862
	 */
863
	unsigned int cpu_power;
864

865 866 867 868 869 870 871 872 873 874 875
	/*
	 * The CPUs this group covers.
	 *
	 * NOTE: this field is variable length. (Allocated dynamically
	 * by attaching extra space to the end of the structure,
	 * depending on how many CPUs the kernel has booted up with)
	 *
	 * It is also be embedded into static data structures at build
	 * time. (See 'struct static_sched_group' in kernel/sched.c)
	 */
	unsigned long cpumask[0];
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};

878 879
static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
{
880
	return to_cpumask(sg->cpumask);
881 882
}

883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900
enum sched_domain_level {
	SD_LV_NONE = 0,
	SD_LV_SIBLING,
	SD_LV_MC,
	SD_LV_CPU,
	SD_LV_NODE,
	SD_LV_ALLNODES,
	SD_LV_MAX
};

struct sched_domain_attr {
	int relax_domain_level;
};

#define SD_ATTR_INIT	(struct sched_domain_attr) {	\
	.relax_domain_level = -1,			\
}

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struct sched_domain {
	/* These fields must be setup */
	struct sched_domain *parent;	/* top domain must be null terminated */
904
	struct sched_domain *child;	/* bottom domain must be null terminated */
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	struct sched_group *groups;	/* the balancing groups of the 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 int cache_nice_tries;	/* Leave cache hot tasks for # tries */
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	unsigned int busy_idx;
	unsigned int idle_idx;
	unsigned int newidle_idx;
	unsigned int wake_idx;
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	unsigned int forkexec_idx;
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	unsigned int smt_gain;
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	int flags;			/* See SD_* */
918
	enum sched_domain_level level;
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	/* 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 */

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	u64 last_update;

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#ifdef CONFIG_SCHEDSTATS
	/* load_balance() stats */
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	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
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	/* Active load balancing */
939 940 941
	unsigned int alb_count;
	unsigned int alb_failed;
	unsigned int alb_pushed;
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943
	/* SD_BALANCE_EXEC stats */
944 945 946
	unsigned int sbe_count;
	unsigned int sbe_balanced;
	unsigned int sbe_pushed;
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948
	/* SD_BALANCE_FORK stats */
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	unsigned int sbf_count;
	unsigned int sbf_balanced;
	unsigned int sbf_pushed;
952

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	/* try_to_wake_up() stats */
954 955 956
	unsigned int ttwu_wake_remote;
	unsigned int ttwu_move_affine;
	unsigned int ttwu_move_balance;
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#endif
958 959 960
#ifdef CONFIG_SCHED_DEBUG
	char *name;
#endif
961

962
	unsigned int span_weight;
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	/*
	 * Span of all CPUs in this domain.
	 *
	 * NOTE: this field is variable length. (Allocated dynamically
	 * by attaching extra space to the end of the structure,
	 * depending on how many CPUs the kernel has booted up with)
	 *
	 * It is also be embedded into static data structures at build
	 * time. (See 'struct static_sched_domain' in kernel/sched.c)
	 */
	unsigned long span[0];
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};

976 977
static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
{
978
	return to_cpumask(sd->span);
979 980
}

981
extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
982
				    struct sched_domain_attr *dattr_new);
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984 985 986 987
/* Allocate an array of sched domains, for partition_sched_domains(). */
cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);

988 989 990 991 992 993 994 995
/* Test a flag in parent sched domain */
static inline int test_sd_parent(struct sched_domain *sd, int flag)
{
	if (sd->parent && (sd->parent->flags & flag))
		return 1;

	return 0;
}
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997 998 999
unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);

1000
#else /* CONFIG_SMP */
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1002
struct sched_domain_attr;
1003

1004
static inline void
1005
partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1006 1007
			struct sched_domain_attr *dattr_new)
{
1008
}
1009
#endif	/* !CONFIG_SMP */
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struct io_context;			/* See blkdev.h */


1015
#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1016
extern void prefetch_stack(struct task_struct *t);
1017 1018 1019
#else
static inline void prefetch_stack(struct task_struct *t) { }
#endif
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struct audit_context;		/* See audit.c */
struct mempolicy;
1023
struct pipe_inode_info;
1024
struct uts_namespace;
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struct rq;
struct sched_domain;

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/*
 * wake flags
 */
#define WF_SYNC		0x01		/* waker goes to sleep after wakup */
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#define WF_FORK		0x02		/* child wakeup after fork */
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1035 1036 1037 1038 1039 1040
#define ENQUEUE_WAKEUP		1
#define ENQUEUE_WAKING		2
#define ENQUEUE_HEAD		4

#define DEQUEUE_SLEEP		1

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struct sched_class {
1042
	const struct sched_class *next;
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1044 1045
	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1046
	void (*yield_task) (struct rq *rq);
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	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
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1050
	struct task_struct * (*pick_next_task) (struct rq *rq);
1051
	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
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1053
#ifdef CONFIG_SMP
1054 1055
	int  (*select_task_rq)(struct rq *rq, struct task_struct *p,
			       int sd_flag, int flags);
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1057 1058
	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
	void (*post_schedule) (struct rq *this_rq);
1059 1060
	void (*task_waking) (struct rq *this_rq, struct task_struct *task);
	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1061

1062
	void (*set_cpus_allowed)(struct task_struct *p,
1063
				 const struct cpumask *newmask);
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1065 1066
	void (*rq_online)(struct rq *rq);
	void (*rq_offline)(struct rq *rq);
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#endif

	void (*set_curr_task) (struct rq *rq);
	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
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	void (*task_fork) (struct task_struct *p);
1072 1073 1074 1075 1076 1077 1078

	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
			       int running);
	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
			     int running);
	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
			     int oldprio, int running);
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1080 1081
	unsigned int (*get_rr_interval) (struct rq *rq,
					 struct task_struct *task);
1082

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#ifdef CONFIG_FAIR_GROUP_SCHED
1084
	void (*moved_group) (struct task_struct *p, int on_rq);
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#endif
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};

struct load_weight {
	unsigned long weight, inv_weight;
};

1092
#ifdef CONFIG_SCHEDSTATS
1093
struct sched_statistics {
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	u64			wait_start;
1095
	u64			wait_max;
1096 1097
	u64			wait_count;
	u64			wait_sum;
1098 1099
	u64			iowait_count;
	u64			iowait_sum;
1100

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	u64			sleep_start;
	u64			sleep_max;
1103 1104 1105
	s64			sum_sleep_runtime;

	u64			block_start;
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	u64			block_max;
	u64			exec_max;
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	u64			slice_max;
1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124

	u64			nr_migrations_cold;
	u64			nr_failed_migrations_affine;
	u64			nr_failed_migrations_running;
	u64			nr_failed_migrations_hot;
	u64			nr_forced_migrations;

	u64			nr_wakeups;
	u64			nr_wakeups_sync;
	u64			nr_wakeups_migrate;
	u64			nr_wakeups_local;
	u64			nr_wakeups_remote;
	u64			nr_wakeups_affine;
	u64			nr_wakeups_affine_attempts;
	u64			nr_wakeups_passive;
	u64			nr_wakeups_idle;
1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142
};
#endif

struct sched_entity {
	struct load_weight	load;		/* for load-balancing */
	struct rb_node		run_node;
	struct list_head	group_node;
	unsigned int		on_rq;

	u64			exec_start;
	u64			sum_exec_runtime;
	u64			vruntime;
	u64			prev_sum_exec_runtime;

	u64			nr_migrations;

#ifdef CONFIG_SCHEDSTATS
	struct sched_statistics statistics;
1143 1144
#endif

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#ifdef CONFIG_FAIR_GROUP_SCHED
	struct sched_entity	*parent;
	/* rq on which this entity is (to be) queued: */
	struct cfs_rq		*cfs_rq;
	/* rq "owned" by this entity/group: */
	struct cfs_rq		*my_q;
#endif
};
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struct sched_rt_entity {
	struct list_head run_list;
1156
	unsigned long timeout;
1157
	unsigned int time_slice;
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	int nr_cpus_allowed;

1160
	struct sched_rt_entity *back;
1161
#ifdef CONFIG_RT_GROUP_SCHED
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	struct sched_rt_entity	*parent;
	/* rq on which this entity is (to be) queued: */
	struct rt_rq		*rt_rq;
	/* rq "owned" by this entity/group: */
	struct rt_rq		*my_q;
#endif
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};

1170 1171
struct rcu_node;

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struct task_struct {
	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
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	void *stack;
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	atomic_t usage;
1176 1177
	unsigned int flags;	/* per process flags, defined below */
	unsigned int ptrace;
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1179
	int lock_depth;		/* BKL lock depth */
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1181 1182
#ifdef CONFIG_SMP
#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1183 1184
	int oncpu;
#endif
1185
#endif
1186

1187
	int prio, static_prio, normal_prio;
1188
	unsigned int rt_priority;
1189
	const struct sched_class *sched_class;
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	struct sched_entity se;
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	struct sched_rt_entity rt;
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1193 1194 1195 1196 1197
#ifdef CONFIG_PREEMPT_NOTIFIERS
	/* list of struct preempt_notifier: */
	struct hlist_head preempt_notifiers;
#endif

1198 1199 1200 1201 1202 1203 1204 1205 1206
	/*
	 * fpu_counter contains the number of consecutive context switches
	 * that the FPU is used. If this is over a threshold, the lazy fpu
	 * saving becomes unlazy to save the trap. This is an unsigned char
	 * so that after 256 times the counter wraps and the behavior turns
	 * lazy again; this to deal with bursty apps that only use FPU for
	 * a short time
	 */
	unsigned char fpu_counter;
1207
#ifdef CONFIG_BLK_DEV_IO_TRACE
1208
	unsigned int btrace_seq;
1209
#endif
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1211
	unsigned int policy;
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	cpumask_t cpus_allowed;

1214
#ifdef CONFIG_TREE_PREEMPT_RCU
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	int rcu_read_lock_nesting;
1216
	char rcu_read_unlock_special;
1217
	struct rcu_node *rcu_blocked_node;
1218 1219
	struct list_head rcu_node_entry;
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
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1221
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
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	struct sched_info sched_info;
#endif

	struct list_head tasks;
1226
	struct plist_node pushable_tasks;
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	struct mm_struct *mm, *active_mm;
1229 1230 1231
#if defined(SPLIT_RSS_COUNTING)
	struct task_rss_stat	rss_stat;
#endif
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/* task state */
1233
	int exit_state;
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	int exit_code, exit_signal;
	int pdeath_signal;  /*  The signal sent when the parent dies  */
	/* ??? */
1237
	unsigned int personality;
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	unsigned did_exec:1;
1239 1240
	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
				 * execve */
1241 1242
	unsigned in_iowait:1;

1243 1244 1245 1246

	/* Revert to default priority/policy when forking */
	unsigned sched_reset_on_fork:1;

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	pid_t pid;
	pid_t tgid;
1249

1250
#ifdef CONFIG_CC_STACKPROTECTOR
1251 1252
	/* Canary value for the -fstack-protector gcc feature */
	unsigned long stack_canary;
1253
#endif
1254

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	/* 
	 * pointers to (original) parent process, youngest child, younger sibling,
	 * older sibling, respectively.  (p->father can be replaced with 
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	 * p->real_parent->pid)
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	 */
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	struct task_struct *real_parent; /* real parent process */
	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
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	/*
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	 * children/sibling forms the list of my natural children
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	 */
	struct list_head children;	/* list of my children */
	struct list_head sibling;	/* linkage in my parent's children list */
	struct task_struct *group_leader;	/* threadgroup leader */

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	/*
	 * ptraced is the list of tasks this task is using ptrace on.
	 * This includes both natural children and PTRACE_ATTACH targets.
	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
	 */
	struct list_head ptraced;
	struct list_head ptrace_entry;

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	/* PID/PID hash table linkage. */
1278
	struct pid_link pids[PIDTYPE_MAX];
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	struct list_head thread_group;
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	struct completion *vfork_done;		/* for vfork() */
	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */

1285
	cputime_t utime, stime, utimescaled, stimescaled;
1286
	cputime_t gtime;
1287
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
1288
	cputime_t prev_utime, prev_stime;
1289
#endif
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	unsigned long nvcsw, nivcsw; /* context switch counts */
1291 1292
	struct timespec start_time; 		/* monotonic time */
	struct timespec real_start_time;	/* boot based time */
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/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
	unsigned long min_flt, maj_flt;

1296
	struct task_cputime cputime_expires;
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	struct list_head cpu_timers[3];

/* process credentials */
1300 1301 1302 1303
	const struct cred *real_cred;	/* objective and real subjective task
					 * credentials (COW) */
	const struct cred *cred;	/* effective (overridable) subjective task
					 * credentials (COW) */
1304 1305 1306
	struct mutex cred_guard_mutex;	/* guard against foreign influences on
					 * credential calculations
					 * (notably. ptrace) */
1307
	struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1308

1309 1310 1311
	char comm[TASK_COMM_LEN]; /* executable name excluding path
				     - access with [gs]et_task_comm (which lock
				       it with task_lock())
1312
				     - initialized normally by setup_new_exec */
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/* file system info */
	int link_count, total_link_count;
1315
#ifdef CONFIG_SYSVIPC
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/* ipc stuff */
	struct sysv_sem sysvsem;
1318
#endif
1319
#ifdef CONFIG_DETECT_HUNG_TASK
1320 1321 1322
/* hung task detection */
	unsigned long last_switch_count;
#endif
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/* CPU-specific state of this task */
	struct thread_struct thread;
/* filesystem information */
	struct fs_struct *fs;
/* open file information */
	struct files_struct *files;
1329
/* namespaces */
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	struct nsproxy *nsproxy;
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/* signal handlers */
	struct signal_struct *signal;
	struct sighand_struct *sighand;

	sigset_t blocked, real_blocked;
1336
	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
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	struct sigpending pending;

	unsigned long sas_ss_sp;
	size_t sas_ss_size;
	int (*notifier)(void *priv);
	void *notifier_data;
	sigset_t *notifier_mask;
	struct audit_context *audit_context;
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#ifdef CONFIG_AUDITSYSCALL
	uid_t loginuid;
1347
	unsigned int sessionid;
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#endif
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	seccomp_t seccomp;

/* Thread group tracking */
   	u32 parent_exec_id;
   	u32 self_exec_id;
1354 1355
/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
 * mempolicy */
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	spinlock_t alloc_lock;

1358 1359 1360 1361 1362
#ifdef CONFIG_GENERIC_HARDIRQS
	/* IRQ handler threads */
	struct irqaction *irqaction;
#endif

1363
	/* Protection of the PI data structures: */
1364
	raw_spinlock_t pi_lock;
1365

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#ifdef CONFIG_RT_MUTEXES
	/* PI waiters blocked on a rt_mutex held by this task */
	struct plist_head pi_waiters;
	/* Deadlock detection and priority inheritance handling */
	struct rt_mutex_waiter *pi_blocked_on;
#endif

1373 1374 1375 1376
#ifdef CONFIG_DEBUG_MUTEXES
	/* mutex deadlock detection */
	struct mutex_waiter *blocked_on;
#endif
1377 1378 1379 1380
#ifdef CONFIG_TRACE_IRQFLAGS
	unsigned int irq_events;
	unsigned long hardirq_enable_ip;
	unsigned long hardirq_disable_ip;
1381
	unsigned int hardirq_enable_event;
1382
	unsigned int hardirq_disable_event;
1383 1384
	int hardirqs_enabled;
	int hardirq_context;
1385 1386
	unsigned long softirq_disable_ip;
	unsigned long softirq_enable_ip;
1387
	unsigned int softirq_disable_event;
1388
	unsigned int softirq_enable_event;
1389
	int softirqs_enabled;
1390 1391
	int softirq_context;
#endif
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#ifdef CONFIG_LOCKDEP
1393
# define MAX_LOCK_DEPTH 48UL
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	u64 curr_chain_key;
	int lockdep_depth;
	unsigned int lockdep_recursion;
1397
	struct held_lock held_locks[MAX_LOCK_DEPTH];
1398
	gfp_t lockdep_reclaim_gfp;
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#endif
1400

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/* journalling filesystem info */
	void *journal_info;

1404
/* stacked block device info */
1405
	struct bio_list *bio_list;
1406

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/* VM state */
	struct reclaim_state *reclaim_state;

	struct backing_dev_info *backing_dev_info;

	struct io_context *io_context;

	unsigned long ptrace_message;
	siginfo_t *last_siginfo; /* For ptrace use.  */
1416
	struct task_io_accounting ioac;
1417
#if defined(CONFIG_TASK_XACCT)
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	u64 acct_rss_mem1;	/* accumulated rss usage */
	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1420
	cputime_t acct_timexpd;	/* stime + utime since last update */
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#endif
#ifdef CONFIG_CPUSETS
1423
	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1424
	int mems_allowed_change_disable;
1425
	int cpuset_mem_spread_rotor;
1426
	int cpuset_slab_spread_rotor;
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#endif
1428
#ifdef CONFIG_CGROUPS
1429 1430 1431 1432
	/* Control Group info protected by css_set_lock */
	struct css_set *cgroups;
	/* cg_list protected by css_set_lock and tsk->alloc_lock */
	struct list_head cg_list;
1433
#endif
1434
#ifdef CONFIG_FUTEX
1435
	struct robust_list_head __user *robust_list;
1436 1437 1438
#ifdef CONFIG_COMPAT
	struct compat_robust_list_head __user *compat_robust_list;
#endif
1439 1440
	struct list_head pi_state_list;
	struct futex_pi_state *pi_state_cache;
1441
#endif
1442 1443 1444 1445
#ifdef CONFIG_PERF_EVENTS
	struct perf_event_context *perf_event_ctxp;
	struct mutex perf_event_mutex;
	struct list_head perf_event_list;
1446
#endif
1447
#ifdef CONFIG_NUMA
1448
	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1449
	short il_next;
1450
#endif
1451
	atomic_t fs_excl;	/* holding fs exclusive resources */
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	struct rcu_head rcu;
1453 1454 1455 1456 1457

	/*
	 * cache last used pipe for splice
	 */
	struct pipe_inode_info *splice_pipe;
1458 1459
#ifdef	CONFIG_TASK_DELAY_ACCT
	struct task_delay_info *delays;
1460 1461 1462
#endif
#ifdef CONFIG_FAULT_INJECTION
	int make_it_fail;
1463
#endif
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	struct prop_local_single dirties;
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#ifdef CONFIG_LATENCYTOP
	int latency_record_count;
	struct latency_record latency_record[LT_SAVECOUNT];
#endif
1469 1470 1471 1472 1473 1474
	/*
	 * time slack values; these are used to round up poll() and
	 * select() etc timeout values. These are in nanoseconds.
	 */
	unsigned long timer_slack_ns;
	unsigned long default_timer_slack_ns;
1475 1476

	struct list_head	*scm_work_list;
1477
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
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	/* Index of current stored address in ret_stack */
1479 1480 1481
	int curr_ret_stack;
	/* Stack of return addresses for return function tracing */
	struct ftrace_ret_stack	*ret_stack;
1482 1483
	/* time stamp for last schedule */
	unsigned long long ftrace_timestamp;
1484 1485 1486 1487 1488
	/*
	 * Number of functions that haven't been traced
	 * because of depth overrun.
	 */
	atomic_t trace_overrun;
1489 1490
	/* Pause for the tracing */
	atomic_t tracing_graph_pause;
1491
#endif
1492 1493 1494
#ifdef CONFIG_TRACING
	/* state flags for use by tracers */
	unsigned long trace;
1495 1496 1497
	/* bitmask of trace recursion */
	unsigned long trace_recursion;
#endif /* CONFIG_TRACING */
1498 1499 1500 1501 1502 1503 1504 1505
#ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
	struct memcg_batch_info {
		int do_batch;	/* incremented when batch uncharge started */
		struct mem_cgroup *memcg; /* target memcg of uncharge */
		unsigned long bytes; 		/* uncharged usage */
		unsigned long memsw_bytes; /* uncharged mem+swap usage */
	} memcg_batch;
#endif
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};

1508
/* Future-safe accessor for struct task_struct's cpus_allowed. */
1509
#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1510

1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536
/*
 * 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 DEFAULT_PRIO		(MAX_RT_PRIO + 20)

static inline int rt_prio(int prio)
{
	if (unlikely(prio < MAX_RT_PRIO))
		return 1;
	return 0;
}

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static inline int rt_task(struct task_struct *p)
1538 1539 1540 1541
{
	return rt_prio(p->prio);
}

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static inline struct pid *task_pid(struct task_struct *task)
1543 1544 1545 1546
{
	return task->pids[PIDTYPE_PID].pid;
}

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static inline struct pid *task_tgid(struct task_struct *task)
1548 1549 1550 1551
{
	return task->group_leader->pids[PIDTYPE_PID].pid;
}

1552 1553 1554 1555 1556
/*
 * Without tasklist or rcu lock it is not safe to dereference
 * the result of task_pgrp/task_session even if task == current,
 * we can race with another thread doing sys_setsid/sys_setpgid.
 */
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1557
static inline struct pid *task_pgrp(struct task_struct *task)
1558 1559 1560 1561
{
	return task->group_leader->pids[PIDTYPE_PGID].pid;
}

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1562
static inline struct pid *task_session(struct task_struct *task)
1563 1564 1565 1566
{
	return task->group_leader->pids[PIDTYPE_SID].pid;
}

1567 1568 1569 1570 1571 1572 1573
struct pid_namespace;

/*
 * the helpers to get the task's different pids as they are seen
 * from various namespaces
 *
 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
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 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
 *                     current.
1576 1577 1578 1579 1580 1581
 * task_xid_nr_ns()  : id seen from the ns specified;
 *
 * set_task_vxid()   : assigns a virtual id to a task;
 *
 * see also pid_nr() etc in include/linux/pid.h
 */
1582 1583
pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
			struct pid_namespace *ns);
1584

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static inline pid_t task_pid_nr(struct task_struct *tsk)
1586 1587 1588 1589
{
	return tsk->pid;
}

1590 1591 1592 1593 1594
static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
{
	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
}
1595 1596 1597

static inline pid_t task_pid_vnr(struct task_struct *tsk)
{
1598
	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1599 1600 1601
}


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Alexey Dobriyan 已提交
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static inline pid_t task_tgid_nr(struct task_struct *tsk)
1603 1604 1605 1606
{
	return tsk->tgid;
}

1607
pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1608 1609 1610 1611 1612 1613 1614

static inline pid_t task_tgid_vnr(struct task_struct *tsk)
{
	return pid_vnr(task_tgid(tsk));
}


1615 1616
static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
1617
{
1618
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1619 1620 1621 1622
}

static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
{
1623
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1624 1625 1626
}


1627 1628
static inline pid_t task_session_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
1629
{
1630
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1631 1632 1633 1634
}

static inline pid_t task_session_vnr(struct task_struct *tsk)
{
1635
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1636 1637
}

1638 1639 1640 1641 1642
/* obsolete, do not use */
static inline pid_t task_pgrp_nr(struct task_struct *tsk)
{
	return task_pgrp_nr_ns(tsk, &init_pid_ns);
}
1643

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Linus Torvalds 已提交
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/**
 * pid_alive - check that a task structure is not stale
 * @p: Task structure to be checked.
 *
 * Test if a process is not yet dead (at most zombie state)
 * If pid_alive fails, then pointers within the task structure
 * can be stale and must not be dereferenced.
 */
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Alexey Dobriyan 已提交
1652
static inline int pid_alive(struct task_struct *p)
L
Linus Torvalds 已提交
1653
{
1654
	return p->pids[PIDTYPE_PID].pid != NULL;
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Linus Torvalds 已提交
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}

1657
/**
1658
 * is_global_init - check if a task structure is init
1659 1660 1661
 * @tsk: Task structure to be checked.
 *
 * Check if a task structure is the first user space task the kernel created.
1662
 */
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Alexey Dobriyan 已提交
1663
static inline int is_global_init(struct task_struct *tsk)
1664 1665 1666
{
	return tsk->pid == 1;
}
1667 1668 1669 1670

/*
 * is_container_init:
 * check whether in the task is init in its own pid namespace.
1671
 */
1672
extern int is_container_init(struct task_struct *tsk);
1673

1674 1675
extern struct pid *cad_pid;

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extern void free_task(struct task_struct *tsk);
#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
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Ingo Molnar 已提交
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1679
extern void __put_task_struct(struct task_struct *t);
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Ingo Molnar 已提交
1680 1681 1682 1683

static inline void put_task_struct(struct task_struct *t)
{
	if (atomic_dec_and_test(&t->usage))
1684
		__put_task_struct(t);
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Ingo Molnar 已提交
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}
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Linus Torvalds 已提交
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1687
extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1688
extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1689

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/*
 * Per process flags
 */
#define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
					/* Not implemented yet, only for 486*/
#define PF_STARTING	0x00000002	/* being created */
#define PF_EXITING	0x00000004	/* getting shut down */
1697
#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1698
#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
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#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1700
#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
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#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
#define PF_DUMPCORE	0x00000200	/* dumped core */
#define PF_SIGNALED	0x00000400	/* killed by a signal */
#define PF_MEMALLOC	0x00000800	/* Allocating memory */
#define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1707
#define PF_FREEZING	0x00004000	/* freeze in progress. do not account to load */
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#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
#define PF_FROZEN	0x00010000	/* frozen for system suspend */
#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
#define PF_KSWAPD	0x00040000	/* I am kswapd */
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Hugh Dickins 已提交
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#define PF_OOM_ORIGIN	0x00080000	/* Allocating much memory to others */
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#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1714
#define PF_KTHREAD	0x00200000	/* I am a kernel thread */
J
Jens Axboe 已提交
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#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
#define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
#define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1719
#define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1720
#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1721
#define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1722
#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
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Rafael J. Wysocki 已提交
1723
#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1724
#define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
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Linus Torvalds 已提交
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/*
 * Only the _current_ task can read/write to tsk->flags, but other
 * tasks can access tsk->flags in readonly mode for example
 * with tsk_used_math (like during threaded core dumping).
 * There is however an exception to this rule during ptrace
 * or during fork: the ptracer task is allowed to write to the
 * child->flags of its traced child (same goes for fork, the parent
 * can write to the child->flags), because we're guaranteed the
 * child is not running and in turn not changing child->flags
 * at the same time the parent does it.
 */
#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
#define clear_used_math() clear_stopped_child_used_math(current)
#define set_used_math() set_stopped_child_used_math(current)
#define conditional_stopped_child_used_math(condition, child) \
	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
#define conditional_used_math(condition) \
	conditional_stopped_child_used_math(condition, current)
#define copy_to_stopped_child_used_math(child) \
	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
#define used_math() tsk_used_math(current)

1751 1752 1753 1754 1755 1756 1757 1758 1759
#ifdef CONFIG_TREE_PREEMPT_RCU

#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
#define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */

static inline void rcu_copy_process(struct task_struct *p)
{
	p->rcu_read_lock_nesting = 0;
	p->rcu_read_unlock_special = 0;
1760
	p->rcu_blocked_node = NULL;
1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771
	INIT_LIST_HEAD(&p->rcu_node_entry);
}

#else

static inline void rcu_copy_process(struct task_struct *p)
{
}

#endif

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#ifdef CONFIG_SMP
1773
extern int set_cpus_allowed_ptr(struct task_struct *p,
1774
				const struct cpumask *new_mask);
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#else
1776
static inline int set_cpus_allowed_ptr(struct task_struct *p,
1777
				       const struct cpumask *new_mask)
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{
1779
	if (!cpumask_test_cpu(0, new_mask))
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		return -EINVAL;
	return 0;
}
#endif
1784 1785

#ifndef CONFIG_CPUMASK_OFFSTACK
1786 1787 1788 1789
static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
{
	return set_cpus_allowed_ptr(p, &new_mask);
}
1790
#endif
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Linus Torvalds 已提交
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1792 1793 1794 1795 1796 1797 1798 1799 1800 1801
/*
 * Architectures can set this to 1 if they have specified
 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
 * but then during bootup it turns out that sched_clock()
 * is reliable after all:
 */
#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
extern int sched_clock_stable;
#endif

1802 1803
/* ftrace calls sched_clock() directly */
extern unsigned long long notrace sched_clock(void);
1804

1805 1806
extern void sched_clock_init(void);
extern u64 sched_clock_cpu(int cpu);
1807

1808
#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825
static inline void sched_clock_tick(void)
{
}

static inline void sched_clock_idle_sleep_event(void)
{
}

static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
{
}
#else
extern void sched_clock_tick(void);
extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
#endif

1826 1827 1828 1829 1830 1831
/*
 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
 * clock constructed from sched_clock():
 */
extern unsigned long long cpu_clock(int cpu);

1832
extern unsigned long long
1833
task_sched_runtime(struct task_struct *task);
1834
extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
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Linus Torvalds 已提交
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/* sched_exec is called by processes performing an exec */
#ifdef CONFIG_SMP
extern void sched_exec(void);
#else
#define sched_exec()   {}
#endif

1843 1844
extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1845

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1846
#ifdef CONFIG_HOTPLUG_CPU
1847
extern void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p);
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extern void idle_task_exit(void);
#else
static inline void idle_task_exit(void) {}
#endif

extern void sched_idle_next(void);
1854

1855 1856 1857 1858 1859 1860
#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
extern void wake_up_idle_cpu(int cpu);
#else
static inline void wake_up_idle_cpu(int cpu) { }
#endif

1861
extern unsigned int sysctl_sched_latency;
1862
extern unsigned int sysctl_sched_min_granularity;
1863
extern unsigned int sysctl_sched_wakeup_granularity;
1864 1865
extern unsigned int sysctl_sched_shares_ratelimit;
extern unsigned int sysctl_sched_shares_thresh;
1866
extern unsigned int sysctl_sched_child_runs_first;
1867 1868 1869 1870 1871 1872 1873 1874 1875

enum sched_tunable_scaling {
	SCHED_TUNABLESCALING_NONE,
	SCHED_TUNABLESCALING_LOG,
	SCHED_TUNABLESCALING_LINEAR,
	SCHED_TUNABLESCALING_END,
};
extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;

1876
#ifdef CONFIG_SCHED_DEBUG
1877
extern unsigned int sysctl_sched_migration_cost;
1878
extern unsigned int sysctl_sched_nr_migrate;
1879
extern unsigned int sysctl_sched_time_avg;
1880
extern unsigned int sysctl_timer_migration;
1881

1882
int sched_proc_update_handler(struct ctl_table *table, int write,
1883
		void __user *buffer, size_t *length,
1884
		loff_t *ppos);
1885
#endif
1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896
#ifdef CONFIG_SCHED_DEBUG
static inline unsigned int get_sysctl_timer_migration(void)
{
	return sysctl_timer_migration;
}
#else
static inline unsigned int get_sysctl_timer_migration(void)
{
	return 1;
}
#endif
P
Peter Zijlstra 已提交
1897 1898
extern unsigned int sysctl_sched_rt_period;
extern int sysctl_sched_rt_runtime;
1899

1900
int sched_rt_handler(struct ctl_table *table, int write,
1901
		void __user *buffer, size_t *lenp,
1902 1903
		loff_t *ppos);

1904
extern unsigned int sysctl_sched_compat_yield;
1905

1906
#ifdef CONFIG_RT_MUTEXES
1907 1908 1909
extern int rt_mutex_getprio(struct task_struct *p);
extern void rt_mutex_setprio(struct task_struct *p, int prio);
extern void rt_mutex_adjust_pi(struct task_struct *p);
1910
#else
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Alexey Dobriyan 已提交
1911
static inline int rt_mutex_getprio(struct task_struct *p)
1912 1913 1914
{
	return p->normal_prio;
}
1915
# define rt_mutex_adjust_pi(p)		do { } while (0)
1916 1917
#endif

1918 1919 1920 1921 1922
extern void set_user_nice(struct task_struct *p, long nice);
extern int task_prio(const struct task_struct *p);
extern int task_nice(const struct task_struct *p);
extern int can_nice(const struct task_struct *p, const int nice);
extern int task_curr(const struct task_struct *p);
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extern int idle_cpu(int cpu);
extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1925 1926
extern int sched_setscheduler_nocheck(struct task_struct *, int,
				      struct sched_param *);
1927 1928 1929
extern struct task_struct *idle_task(int cpu);
extern struct task_struct *curr_task(int cpu);
extern void set_curr_task(int cpu, struct task_struct *p);
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void yield(void);

/*
 * The default (Linux) execution domain.
 */
extern struct exec_domain	default_exec_domain;

union thread_union {
	struct thread_info thread_info;
	unsigned long stack[THREAD_SIZE/sizeof(long)];
};

#ifndef __HAVE_ARCH_KSTACK_END
static inline int kstack_end(void *addr)
{
	/* Reliable end of stack detection:
	 * Some APM bios versions misalign the stack
	 */
	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
}
#endif

extern union thread_union init_thread_union;
extern struct task_struct init_task;

extern struct   mm_struct init_mm;

1958 1959 1960 1961 1962 1963 1964
extern struct pid_namespace init_pid_ns;

/*
 * find a task by one of its numerical ids
 *
 * find_task_by_pid_ns():
 *      finds a task by its pid in the specified namespace
1965 1966
 * find_task_by_vpid():
 *      finds a task by its virtual pid
1967
 *
1968
 * see also find_vpid() etc in include/linux/pid.h
1969 1970
 */

1971 1972 1973
extern struct task_struct *find_task_by_vpid(pid_t nr);
extern struct task_struct *find_task_by_pid_ns(pid_t nr,
		struct pid_namespace *ns);
1974

1975
extern void __set_special_pids(struct pid *pid);
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/* per-UID process charging. */
1978
extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
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static inline struct user_struct *get_uid(struct user_struct *u)
{
	atomic_inc(&u->__count);
	return u;
}
extern void free_uid(struct user_struct *);
1985
extern void release_uids(struct user_namespace *ns);
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#include <asm/current.h>

1989
extern void do_timer(unsigned long ticks);
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Linus Torvalds 已提交
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1991 1992 1993 1994
extern int wake_up_state(struct task_struct *tsk, unsigned int state);
extern int wake_up_process(struct task_struct *tsk);
extern void wake_up_new_task(struct task_struct *tsk,
				unsigned long clone_flags);
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#ifdef CONFIG_SMP
 extern void kick_process(struct task_struct *tsk);
#else
 static inline void kick_process(struct task_struct *tsk) { }
#endif
2000 2001
extern void sched_fork(struct task_struct *p, int clone_flags);
extern void sched_dead(struct task_struct *p);
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extern void proc_caches_init(void);
extern void flush_signals(struct task_struct *);
2005
extern void __flush_signals(struct task_struct *);
2006
extern void ignore_signals(struct task_struct *);
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extern void flush_signal_handlers(struct task_struct *, int force_default);
extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);

static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
{
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&tsk->sighand->siglock, flags);
	ret = dequeue_signal(tsk, mask, info);
	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);

	return ret;
}	

extern void block_all_signals(int (*notifier)(void *priv), void *priv,
			      sigset_t *mask);
extern void unblock_all_signals(void);
extern void release_task(struct task_struct * p);
extern int send_sig_info(int, struct siginfo *, struct task_struct *);
extern int force_sigsegv(int, struct task_struct *);
extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2029 2030
extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2031
extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2032 2033
extern int kill_pgrp(struct pid *pid, int sig, int priv);
extern int kill_pid(struct pid *pid, int sig, int priv);
2034
extern int kill_proc_info(int, struct siginfo *, pid_t);
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Roland McGrath 已提交
2035
extern int do_notify_parent(struct task_struct *, int);
2036
extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
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extern void force_sig(int, struct task_struct *);
extern int send_sig(int, struct task_struct *, int);
2039
extern int zap_other_threads(struct task_struct *p);
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2040 2041
extern struct sigqueue *sigqueue_alloc(void);
extern void sigqueue_free(struct sigqueue *);
2042
extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2043
extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
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2044 2045
extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);

2046 2047 2048 2049 2050
static inline int kill_cad_pid(int sig, int priv)
{
	return kill_pid(cad_pid, sig, priv);
}

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/* These can be the second arg to send_sig_info/send_group_sig_info.  */
#define SEND_SIG_NOINFO ((struct siginfo *) 0)
#define SEND_SIG_PRIV	((struct siginfo *) 1)
#define SEND_SIG_FORCED	((struct siginfo *) 2)

2056 2057 2058
/*
 * True if we are on the alternate signal stack.
 */
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2059 2060
static inline int on_sig_stack(unsigned long sp)
{
2061 2062 2063 2064 2065 2066 2067
#ifdef CONFIG_STACK_GROWSUP
	return sp >= current->sas_ss_sp &&
		sp - current->sas_ss_sp < current->sas_ss_size;
#else
	return sp > current->sas_ss_sp &&
		sp - current->sas_ss_sp <= current->sas_ss_size;
#endif
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}

static inline int sas_ss_flags(unsigned long sp)
{
	return (current->sas_ss_size == 0 ? SS_DISABLE
		: on_sig_stack(sp) ? SS_ONSTACK : 0);
}

/*
 * Routines for handling mm_structs
 */
extern struct mm_struct * mm_alloc(void);

/* mmdrop drops the mm and the page tables */
2082
extern void __mmdrop(struct mm_struct *);
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Linus Torvalds 已提交
2083 2084
static inline void mmdrop(struct mm_struct * mm)
{
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Ingo Molnar 已提交
2085
	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
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		__mmdrop(mm);
}

/* mmput gets rid of the mappings and all user-space */
extern void mmput(struct mm_struct *);
/* Grab a reference to a task's mm, if it is not already going away */
extern struct mm_struct *get_task_mm(struct task_struct *task);
/* Remove the current tasks stale references to the old mm_struct */
extern void mm_release(struct task_struct *, struct mm_struct *);
2095 2096
/* Allocate a new mm structure and copy contents from tsk->mm */
extern struct mm_struct *dup_mm(struct task_struct *tsk);
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2098 2099
extern int copy_thread(unsigned long, unsigned long, unsigned long,
			struct task_struct *, struct pt_regs *);
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2100 2101 2102 2103
extern void flush_thread(void);
extern void exit_thread(void);

extern void exit_files(struct task_struct *);
2104
extern void __cleanup_sighand(struct sighand_struct *);
2105

L
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extern void exit_itimers(struct signal_struct *);
2107
extern void flush_itimer_signals(void);
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extern NORET_TYPE void do_group_exit(int);

extern void daemonize(const char *, ...);
extern int allow_signal(int);
extern int disallow_signal(int);

extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2117
struct task_struct *fork_idle(int);
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extern void set_task_comm(struct task_struct *tsk, char *from);
2120
extern char *get_task_comm(char *to, struct task_struct *tsk);
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#ifdef CONFIG_SMP
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extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
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#else
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static inline unsigned long wait_task_inactive(struct task_struct *p,
					       long match_state)
{
	return 1;
}
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#endif

2132 2133
#define next_task(p) \
	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
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#define for_each_process(p) \
	for (p = &init_task ; (p = next_task(p)) != &init_task ; )

2138
extern bool current_is_single_threaded(void);
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/*
 * Careful: do_each_thread/while_each_thread is a double loop so
 *          'break' will not work as expected - use goto instead.
 */
#define do_each_thread(g, t) \
	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do

#define while_each_thread(g, t) \
	while ((t = next_thread(t)) != g)

2150 2151
static inline int get_nr_threads(struct task_struct *tsk)
{
2152
	return tsk->signal->nr_threads;
2153 2154
}

2155 2156
/* de_thread depends on thread_group_leader not being a pid based check */
#define thread_group_leader(p)	(p == p->group_leader)
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2158 2159 2160 2161 2162 2163
/* Do to the insanities of de_thread it is possible for a process
 * to have the pid of the thread group leader without actually being
 * the thread group leader.  For iteration through the pids in proc
 * all we care about is that we have a task with the appropriate
 * pid, we don't actually care if we have the right task.
 */
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static inline int has_group_leader_pid(struct task_struct *p)
2165 2166 2167 2168
{
	return p->pid == p->tgid;
}

2169 2170 2171 2172 2173 2174
static inline
int same_thread_group(struct task_struct *p1, struct task_struct *p2)
{
	return p1->tgid == p2->tgid;
}

2175
static inline struct task_struct *next_thread(const struct task_struct *p)
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{
2177 2178
	return list_entry_rcu(p->thread_group.next,
			      struct task_struct, thread_group);
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}

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static inline int thread_group_empty(struct task_struct *p)
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{
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	return list_empty(&p->thread_group);
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}

#define delay_group_leader(p) \
		(thread_group_leader(p) && !thread_group_empty(p))

2189 2190 2191 2192 2193
static inline int task_detached(struct task_struct *p)
{
	return p->exit_signal == -1;
}

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/*
2195
 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2196
 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2197 2198
 * pins the final release of task.io_context.  Also protects ->cpuset and
 * ->cgroup.subsys[].
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 *
 * Nests both inside and outside of read_lock(&tasklist_lock).
 * It must not be nested with write_lock_irq(&tasklist_lock),
 * neither inside nor outside.
 */
static inline void task_lock(struct task_struct *p)
{
	spin_lock(&p->alloc_lock);
}

static inline void task_unlock(struct task_struct *p)
{
	spin_unlock(&p->alloc_lock);
}

2214 2215 2216 2217 2218 2219 2220 2221 2222
extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
							unsigned long *flags);

static inline void unlock_task_sighand(struct task_struct *tsk,
						unsigned long *flags)
{
	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
}

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#ifndef __HAVE_THREAD_FUNCTIONS

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#define task_thread_info(task)	((struct thread_info *)(task)->stack)
#define task_stack_page(task)	((task)->stack)
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2228 2229 2230 2231 2232 2233 2234 2235
static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
{
	*task_thread_info(p) = *task_thread_info(org);
	task_thread_info(p)->task = p;
}

static inline unsigned long *end_of_stack(struct task_struct *p)
{
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	return (unsigned long *)(task_thread_info(p) + 1);
2237 2238
}

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#endif

2241 2242 2243 2244 2245 2246 2247
static inline int object_is_on_stack(void *obj)
{
	void *stack = task_stack_page(current);

	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
}

2248 2249
extern void thread_info_cache_init(void);

2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262
#ifdef CONFIG_DEBUG_STACK_USAGE
static inline unsigned long stack_not_used(struct task_struct *p)
{
	unsigned long *n = end_of_stack(p);

	do { 	/* Skip over canary */
		n++;
	} while (!*n);

	return (unsigned long)n - (unsigned long)end_of_stack(p);
}
#endif

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/* set thread flags in other task's structures
 * - see asm/thread_info.h for TIF_xxxx flags available
 */
static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
{
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	set_ti_thread_flag(task_thread_info(tsk), flag);
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}

static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
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	clear_ti_thread_flag(task_thread_info(tsk), flag);
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}

static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
{
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	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
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}

static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
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	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
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}

static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
{
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	return test_ti_thread_flag(task_thread_info(tsk), flag);
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}

static inline void set_tsk_need_resched(struct task_struct *tsk)
{
	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
}

static inline void clear_tsk_need_resched(struct task_struct *tsk)
{
	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
}

2301 2302 2303 2304 2305
static inline int test_tsk_need_resched(struct task_struct *tsk)
{
	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
}

2306 2307 2308 2309 2310 2311
static inline int restart_syscall(void)
{
	set_tsk_thread_flag(current, TIF_SIGPENDING);
	return -ERESTARTNOINTR;
}

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static inline int signal_pending(struct task_struct *p)
{
	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
}
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2317 2318 2319 2320
static inline int __fatal_signal_pending(struct task_struct *p)
{
	return unlikely(sigismember(&p->pending.signal, SIGKILL));
}
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static inline int fatal_signal_pending(struct task_struct *p)
{
	return signal_pending(p) && __fatal_signal_pending(p);
}

2327 2328 2329 2330 2331 2332 2333 2334 2335 2336
static inline int signal_pending_state(long state, struct task_struct *p)
{
	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
		return 0;
	if (!signal_pending(p))
		return 0;

	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
}

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static inline int need_resched(void)
{
2339
	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
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}

/*
 * cond_resched() and cond_resched_lock(): latency reduction via
 * explicit rescheduling in places that are safe. The return
 * value indicates whether a reschedule was done in fact.
 * cond_resched_lock() will drop the spinlock before scheduling,
 * cond_resched_softirq() will enable bhs before scheduling.
 */
2349
extern int _cond_resched(void);
2350

2351 2352 2353 2354
#define cond_resched() ({			\
	__might_sleep(__FILE__, __LINE__, 0);	\
	_cond_resched();			\
})
2355

2356 2357
extern int __cond_resched_lock(spinlock_t *lock);

2358 2359
#ifdef CONFIG_PREEMPT
#define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2360
#else
2361
#define PREEMPT_LOCK_OFFSET	0
2362
#endif
2363

2364
#define cond_resched_lock(lock) ({				\
2365
	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2366 2367 2368 2369 2370 2371 2372 2373 2374
	__cond_resched_lock(lock);				\
})

extern int __cond_resched_softirq(void);

#define cond_resched_softirq() ({				\
	__might_sleep(__FILE__, __LINE__, SOFTIRQ_OFFSET);	\
	__cond_resched_softirq();				\
})
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/*
 * Does a critical section need to be broken due to another
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 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
 * but a general need for low latency)
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 */
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static inline int spin_needbreak(spinlock_t *lock)
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{
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2383 2384 2385
#ifdef CONFIG_PREEMPT
	return spin_is_contended(lock);
#else
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	return 0;
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2387
#endif
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}

2390 2391 2392
/*
 * Thread group CPU time accounting.
 */
2393
void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2394
void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2395

2396
static inline void thread_group_cputime_init(struct signal_struct *sig)
2397
{
2398
	spin_lock_init(&sig->cputimer.lock);
2399 2400
}

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/*
 * Reevaluate whether the task has signals pending delivery.
 * Wake the task if so.
 * This is required every time the blocked sigset_t changes.
 * callers must hold sighand->siglock.
 */
extern void recalc_sigpending_and_wake(struct task_struct *t);
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extern void recalc_sigpending(void);

extern void signal_wake_up(struct task_struct *t, int resume_stopped);

/*
 * Wrappers for p->thread_info->cpu access. No-op on UP.
 */
#ifdef CONFIG_SMP

static inline unsigned int task_cpu(const struct task_struct *p)
{
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	return task_thread_info(p)->cpu;
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}

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extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
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#else

static inline unsigned int task_cpu(const struct task_struct *p)
{
	return 0;
}

static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
{
}

#endif /* CONFIG_SMP */

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#ifdef CONFIG_TRACING
extern void
__trace_special(void *__tr, void *__data,
		unsigned long arg1, unsigned long arg2, unsigned long arg3);
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#else
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static inline void
__trace_special(void *__tr, void *__data,
		unsigned long arg1, unsigned long arg2, unsigned long arg3)
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{
}
#endif

2449 2450
extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2451

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extern void normalize_rt_tasks(void);

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#ifdef CONFIG_CGROUP_SCHED
2455

2456
extern struct task_group init_task_group;
2457

2458
extern struct task_group *sched_create_group(struct task_group *parent);
2459
extern void sched_destroy_group(struct task_group *tg);
2460
extern void sched_move_task(struct task_struct *tsk);
2461
#ifdef CONFIG_FAIR_GROUP_SCHED
2462
extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2463
extern unsigned long sched_group_shares(struct task_group *tg);
2464 2465
#endif
#ifdef CONFIG_RT_GROUP_SCHED
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Peter Zijlstra 已提交
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extern int sched_group_set_rt_runtime(struct task_group *tg,
				      long rt_runtime_us);
extern long sched_group_rt_runtime(struct task_group *tg);
2469 2470 2471
extern int sched_group_set_rt_period(struct task_group *tg,
				      long rt_period_us);
extern long sched_group_rt_period(struct task_group *tg);
2472
extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2473
#endif
2474 2475
#endif

2476 2477 2478
extern int task_can_switch_user(struct user_struct *up,
					struct task_struct *tsk);

2479 2480 2481
#ifdef CONFIG_TASK_XACCT
static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
{
2482
	tsk->ioac.rchar += amt;
2483 2484 2485 2486
}

static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
{
2487
	tsk->ioac.wchar += amt;
2488 2489 2490 2491
}

static inline void inc_syscr(struct task_struct *tsk)
{
2492
	tsk->ioac.syscr++;
2493 2494 2495 2496
}

static inline void inc_syscw(struct task_struct *tsk)
{
2497
	tsk->ioac.syscw++;
2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516
}
#else
static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
{
}

static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
{
}

static inline void inc_syscr(struct task_struct *tsk)
{
}

static inline void inc_syscw(struct task_struct *tsk)
{
}
#endif

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#ifndef TASK_SIZE_OF
#define TASK_SIZE_OF(tsk)	TASK_SIZE
#endif

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/*
 * Call the function if the target task is executing on a CPU right now:
 */
extern void task_oncpu_function_call(struct task_struct *p,
				     void (*func) (void *info), void *info);


2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540
#ifdef CONFIG_MM_OWNER
extern void mm_update_next_owner(struct mm_struct *mm);
extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
#else
static inline void mm_update_next_owner(struct mm_struct *mm)
{
}

static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
{
}
#endif /* CONFIG_MM_OWNER */

2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562
static inline unsigned long task_rlimit(const struct task_struct *tsk,
		unsigned int limit)
{
	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
}

static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
		unsigned int limit)
{
	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
}

static inline unsigned long rlimit(unsigned int limit)
{
	return task_rlimit(current, limit);
}

static inline unsigned long rlimit_max(unsigned int limit)
{
	return task_rlimit_max(current, limit);
}

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#endif /* __KERNEL__ */

#endif