sched.h 91.0 KB
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#ifndef _LINUX_SCHED_H
#define _LINUX_SCHED_H

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#include <uapi/linux/sched.h>
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#include <linux/sched/prio.h>

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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>
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#include <linux/plist.h>
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#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 <linux/preempt.h>
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#include <asm/page.h>
#include <asm/ptrace.h>
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#include <linux/cputime.h>
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#include <linux/smp.h>
#include <linux/sem.h>
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#include <linux/shm.h>
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#include <linux/signal.h>
#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/latencytop.h>
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#include <linux/cred.h>
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#include <linux/llist.h>
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#include <linux/uidgid.h>
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#include <linux/gfp.h>
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#include <linux/magic.h>
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#include <linux/cgroup-defs.h>
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#include <asm/processor.h>
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#define SCHED_ATTR_SIZE_VER0	48	/* sizeof first published struct */

/*
 * Extended scheduling parameters data structure.
 *
 * This is needed because the original struct sched_param can not be
 * altered without introducing ABI issues with legacy applications
 * (e.g., in sched_getparam()).
 *
 * However, the possibility of specifying more than just a priority for
 * the tasks may be useful for a wide variety of application fields, e.g.,
 * multimedia, streaming, automation and control, and many others.
 *
 * This variant (sched_attr) is meant at describing a so-called
 * sporadic time-constrained task. In such model a task is specified by:
 *  - the activation period or minimum instance inter-arrival time;
 *  - the maximum (or average, depending on the actual scheduling
 *    discipline) computation time of all instances, a.k.a. runtime;
 *  - the deadline (relative to the actual activation time) of each
 *    instance.
 * Very briefly, a periodic (sporadic) task asks for the execution of
 * some specific computation --which is typically called an instance--
 * (at most) every period. Moreover, each instance typically lasts no more
 * than the runtime and must be completed by time instant t equal to
 * the instance activation time + the deadline.
 *
 * This is reflected by the actual fields of the sched_attr structure:
 *
 *  @size		size of the structure, for fwd/bwd compat.
 *
 *  @sched_policy	task's scheduling policy
 *  @sched_flags	for customizing the scheduler behaviour
 *  @sched_nice		task's nice value      (SCHED_NORMAL/BATCH)
 *  @sched_priority	task's static priority (SCHED_FIFO/RR)
 *  @sched_deadline	representative of the task's deadline
 *  @sched_runtime	representative of the task's runtime
 *  @sched_period	representative of the task's period
 *
 * Given this task model, there are a multiplicity of scheduling algorithms
 * and policies, that can be used to ensure all the tasks will make their
 * timing constraints.
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 *
 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
 * only user of this new interface. More information about the algorithm
 * available in the scheduling class file or in Documentation/.
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 */
struct sched_attr {
	u32 size;

	u32 sched_policy;
	u64 sched_flags;

	/* SCHED_NORMAL, SCHED_BATCH */
	s32 sched_nice;

	/* SCHED_FIFO, SCHED_RR */
	u32 sched_priority;

	/* SCHED_DEADLINE */
	u64 sched_runtime;
	u64 sched_deadline;
	u64 sched_period;
};

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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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struct blk_plug;
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struct filename;
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struct nameidata;
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#define VMACACHE_BITS 2
#define VMACACHE_SIZE (1U << VMACACHE_BITS)
#define VMACACHE_MASK (VMACACHE_SIZE - 1)

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/*
 * 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);
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extern bool single_task_running(void);
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extern unsigned long nr_iowait(void);
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extern unsigned long nr_iowait_cpu(int cpu);
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extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
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extern void calc_global_load(unsigned long ticks);
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#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
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extern void update_cpu_load_nohz(void);
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#else
static inline void update_cpu_load_nohz(void) { }
#endif
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extern unsigned long get_parent_ip(unsigned long addr);

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extern void dump_cpu_task(int cpu);

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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);
#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 */
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#define EXIT_DEAD		16
#define EXIT_ZOMBIE		32
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#define EXIT_TRACE		(EXIT_ZOMBIE | EXIT_DEAD)
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/* 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_PARKED		512
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#define TASK_NOLOAD		1024
#define TASK_STATE_MAX		2048
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#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN"
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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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#define TASK_IDLE		(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)

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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 | \
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				 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
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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_FROZEN) == 0 && \
				 (task->state & TASK_NOLOAD) == 0)
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#ifdef CONFIG_DEBUG_ATOMIC_SLEEP

#define __set_task_state(tsk, state_value)			\
	do {							\
		(tsk)->task_state_change = _THIS_IP_;		\
		(tsk)->state = (state_value);			\
	} while (0)
#define set_task_state(tsk, state_value)			\
	do {							\
		(tsk)->task_state_change = _THIS_IP_;		\
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		smp_store_mb((tsk)->state, (state_value));		\
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	} while (0)

/*
 * 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()
 */
#define __set_current_state(state_value)			\
	do {							\
		current->task_state_change = _THIS_IP_;		\
		current->state = (state_value);			\
	} while (0)
#define set_current_state(state_value)				\
	do {							\
		current->task_state_change = _THIS_IP_;		\
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		smp_store_mb(current->state, (state_value));		\
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	} while (0)

#else

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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)		\
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	smp_store_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)		\
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	do { current->state = (state_value); } while (0)
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#define set_current_state(state_value)			\
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	smp_store_mb(current->state, (state_value))
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#endif

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/* 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 cpumask_var_t cpu_isolated_map;

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extern int runqueue_is_locked(int cpu);
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#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
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extern void nohz_balance_enter_idle(int cpu);
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extern void set_cpu_sd_state_idle(void);
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extern int get_nohz_timer_target(void);
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#else
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static inline void nohz_balance_enter_idle(int cpu) { }
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static inline void set_cpu_sd_state_idle(void) { }
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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);

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_LOCKUP_DETECTOR
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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_dowatchdog_thresh(struct ctl_table *table, int write,
				  void __user *buffer,
				  size_t *lenp, loff_t *ppos);
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extern unsigned int  softlockup_panic;
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extern unsigned int  hardlockup_panic;
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void lockup_detector_init(void);
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#else
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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static inline void lockup_detector_init(void)
{
}
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#endif

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#ifdef CONFIG_DETECT_HUNG_TASK
void reset_hung_task_detector(void);
#else
static inline void reset_hung_task_detector(void)
{
}
#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 void schedule_preempt_disabled(void);
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extern long io_schedule_timeout(long timeout);

static inline void io_schedule(void)
{
	io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
}

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struct nsproxy;
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struct user_namespace;
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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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#else
static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
#endif
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#define SUID_DUMP_DISABLE	0	/* No setuid dumping */
#define SUID_DUMP_USER		1	/* Dump as user of process */
#define SUID_DUMP_ROOT		2	/* Dump as root */

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/* mm flags */
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/* for SUID_DUMP_* above */
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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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extern void set_dumpable(struct mm_struct *mm, int value);
/*
 * This returns the actual value of the suid_dumpable flag. For things
 * that are using this for checking for privilege transitions, it must
 * test against SUID_DUMP_USER rather than treating it as a boolean
 * value.
 */
static inline int __get_dumpable(unsigned long mm_flags)
{
	return mm_flags & MMF_DUMPABLE_MASK;
}

static inline int get_dumpable(struct mm_struct *mm)
{
	return __get_dumpable(mm->flags);
}

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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_DAX_PRIVATE	9
#define MMF_DUMP_DAX_SHARED	10
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#define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
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#define MMF_DUMP_FILTER_BITS	9
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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 */
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#define MMF_VM_HUGEPAGE		17	/* set when VM_HUGEPAGE is set on vma */
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#define MMF_EXE_FILE_CHANGED	18	/* see prctl_set_mm_exe_file() */
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#define MMF_HAS_UPROBES		19	/* has uprobes */
#define MMF_RECALC_UPROBES	20	/* MMF_HAS_UPROBES can be wrong */
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#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;
526 527
};

528 529 530
struct cpu_itimer {
	cputime_t expires;
	cputime_t incr;
531 532
	u32 error;
	u32 incr_error;
533 534
};

535
/**
536
 * struct prev_cputime - snaphsot of system and user cputime
537 538
 * @utime: time spent in user mode
 * @stime: time spent in system mode
539
 * @lock: protects the above two fields
540
 *
541 542
 * Stores previous user/system time values such that we can guarantee
 * monotonicity.
543
 */
544 545
struct prev_cputime {
#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
546 547
	cputime_t utime;
	cputime_t stime;
548 549
	raw_spinlock_t lock;
#endif
550 551
};

552 553 554 555 556 557 558 559
static inline void prev_cputime_init(struct prev_cputime *prev)
{
#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
	prev->utime = prev->stime = 0;
	raw_spin_lock_init(&prev->lock);
#endif
}

560 561 562 563 564
/**
 * 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
565
 *
566 567 568
 * 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.
569 570 571 572 573 574
 */
struct task_cputime {
	cputime_t utime;
	cputime_t stime;
	unsigned long long sum_exec_runtime;
};
575

576 577
/* Alternate field names when used to cache expirations. */
#define virt_exp	utime
578
#define prof_exp	stime
579 580
#define sched_exp	sum_exec_runtime

581 582
#define INIT_CPUTIME	\
	(struct task_cputime) {					\
583 584
		.utime = 0,					\
		.stime = 0,					\
585 586 587
		.sum_exec_runtime = 0,				\
	}

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/*
 * This is the atomic variant of task_cputime, which can be used for
 * storing and updating task_cputime statistics without locking.
 */
struct task_cputime_atomic {
	atomic64_t utime;
	atomic64_t stime;
	atomic64_t sum_exec_runtime;
};

#define INIT_CPUTIME_ATOMIC \
	(struct task_cputime_atomic) {				\
		.utime = ATOMIC64_INIT(0),			\
		.stime = ATOMIC64_INIT(0),			\
		.sum_exec_runtime = ATOMIC64_INIT(0),		\
	}

605
#define PREEMPT_DISABLED	(PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
606

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/*
608 609
 * Disable preemption until the scheduler is running -- use an unconditional
 * value so that it also works on !PREEMPT_COUNT kernels.
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 *
611
 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
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 */
613
#define INIT_PREEMPT_COUNT	PREEMPT_OFFSET
614

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/*
616 617
 * Initial preempt_count value; reflects the preempt_count schedule invariant
 * which states that during context switches:
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 *
619 620 621 622
 *    preempt_count() == 2*PREEMPT_DISABLE_OFFSET
 *
 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
 * Note: See finish_task_switch().
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 */
624
#define FORK_PREEMPT_COUNT	(2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
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626
/**
627
 * struct thread_group_cputimer - thread group interval timer counts
628
 * @cputime_atomic:	atomic thread group interval timers.
629 630
 * @running:		true when there are timers running and
 *			@cputime_atomic receives updates.
631 632
 * @checking_timer:	true when a thread in the group is in the
 *			process of checking for thread group timers.
633 634
 *
 * This structure contains the version of task_cputime, above, that is
635
 * used for thread group CPU timer calculations.
636
 */
637
struct thread_group_cputimer {
638
	struct task_cputime_atomic cputime_atomic;
639
	bool running;
640
	bool checking_timer;
641 642
};

643
#include <linux/rwsem.h>
644 645
struct autogroup;

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/*
647
 * NOTE! "signal_struct" does not have its own
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 * 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 {
654
	atomic_t		sigcnt;
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	atomic_t		live;
656
	int			nr_threads;
657
	struct list_head	thread_head;
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	wait_queue_head_t	wait_chldexit;	/* for wait4() */

	/* current thread group signal load-balancing target: */
662
	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;
675
	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 */

681 682 683 684 685 686 687 688 689 690 691 692
	/*
	 * PR_SET_CHILD_SUBREAPER marks a process, like a service
	 * manager, to re-parent orphan (double-forking) child processes
	 * to this process instead of 'init'. The service manager is
	 * able to receive SIGCHLD signals and is able to investigate
	 * the process until it calls wait(). All children of this
	 * process will inherit a flag if they should look for a
	 * child_subreaper process at exit.
	 */
	unsigned int		is_child_subreaper:1;
	unsigned int		has_child_subreaper:1;

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	/* POSIX.1b Interval Timers */
694 695
	int			posix_timer_id;
	struct list_head	posix_timers;
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	/* ITIMER_REAL timer for the process */
698
	struct hrtimer real_timer;
699
	struct pid *leader_pid;
700
	ktime_t it_real_incr;
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702 703 704 705 706 707
	/*
	 * 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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709
	/*
710 711
	 * Thread group totals for process CPU timers.
	 * See thread_group_cputimer(), et al, for details.
712
	 */
713
	struct thread_group_cputimer cputimer;
714 715 716 717 718 719

	/* Earliest-expiration cache. */
	struct task_cputime cputime_expires;

	struct list_head cpu_timers[3];

720
	struct pid *tty_old_pgrp;
721

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

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

727 728 729
#ifdef CONFIG_SCHED_AUTOGROUP
	struct autogroup *autogroup;
#endif
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	/*
	 * 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.
	 */
736
	seqlock_t stats_lock;
737
	cputime_t utime, stime, cutime, cstime;
738 739
	cputime_t gtime;
	cputime_t cgtime;
740
	struct prev_cputime prev_cputime;
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	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
743
	unsigned long inblock, oublock, cinblock, coublock;
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	unsigned long maxrss, cmaxrss;
745
	struct task_io_accounting ioac;
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747 748 749 750 751 752 753 754
	/*
	 * 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];

766 767 768
#ifdef CONFIG_BSD_PROCESS_ACCT
	struct pacct_struct pacct;	/* per-process accounting information */
#endif
769 770 771
#ifdef CONFIG_TASKSTATS
	struct taskstats *stats;
#endif
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#ifdef CONFIG_AUDIT
	unsigned audit_tty;
774
	unsigned audit_tty_log_passwd;
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	struct tty_audit_buf *tty_audit_buf;
#endif
777

778
	oom_flags_t oom_flags;
779 780 781
	short oom_score_adj;		/* OOM kill score adjustment */
	short oom_score_adj_min;	/* OOM kill score adjustment min value.
					 * Only settable by CAP_SYS_RESOURCE. */
782 783 784 785

	struct mutex cred_guard_mutex;	/* guard against foreign influences on
					 * credential calculations
					 * (notably. ptrace) */
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};

/*
 * Bits in flags field of signal_struct.
 */
#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
792 793
#define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */
#define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */
794
#define SIGNAL_GROUP_COREDUMP	0x00000008 /* coredump in progress */
795 796 797 798 799 800
/*
 * 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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802 803
#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */

804 805 806 807 808 809 810
/* 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 sigpending;	/* How many pending signals does this user have? */
818
#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
822 823 824
#ifdef CONFIG_FANOTIFY
	atomic_t fanotify_listeners;
#endif
825
#ifdef CONFIG_EPOLL
826
	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
827
#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;
841
	kuid_t uid;
842

843
#if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
844 845
	atomic_long_t locked_vm;
#endif
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};

848
extern int uids_sysfs_init(void);
849

850
extern struct user_struct *find_user(kuid_t);
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extern struct user_struct root_user;
#define INIT_USER (&root_user)

855

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struct backing_dev_info;
struct reclaim_state;

859
#ifdef CONFIG_SCHED_INFO
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struct sched_info {
	/* cumulative counters */
862
	unsigned long pcount;	      /* # of times run on this cpu */
863
	unsigned long long run_delay; /* time spent waiting on a runqueue */
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	/* timestamps */
866 867
	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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868
};
869
#endif /* CONFIG_SCHED_INFO */
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871 872 873 874 875 876 877 878 879 880 881 882 883 884
#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).
	 */
885 886 887 888 889 890

	/*
	 * 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.
	 */
891
	u64 blkio_start;	/* Shared by blkio, swapin */
892 893 894 895 896 897
	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 */
898

899
	u64 freepages_start;
900 901
	u64 freepages_delay;	/* wait for memory reclaim */
	u32 freepages_count;	/* total count of memory reclaim */
902
};
903 904 905 906 907 908 909 910 911 912 913
#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;
914
#endif
915
}
916

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enum cpu_idle_type {
	CPU_IDLE,
	CPU_NOT_IDLE,
	CPU_NEWLY_IDLE,
	CPU_MAX_IDLE_TYPES
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922 923
};

924
/*
925
 * Increase resolution of cpu_capacity calculations
926
 */
927 928
#define SCHED_CAPACITY_SHIFT	10
#define SCHED_CAPACITY_SCALE	(1L << SCHED_CAPACITY_SHIFT)
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930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973
/*
 * Wake-queues are lists of tasks with a pending wakeup, whose
 * callers have already marked the task as woken internally,
 * and can thus carry on. A common use case is being able to
 * do the wakeups once the corresponding user lock as been
 * released.
 *
 * We hold reference to each task in the list across the wakeup,
 * thus guaranteeing that the memory is still valid by the time
 * the actual wakeups are performed in wake_up_q().
 *
 * One per task suffices, because there's never a need for a task to be
 * in two wake queues simultaneously; it is forbidden to abandon a task
 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
 * already in a wake queue, the wakeup will happen soon and the second
 * waker can just skip it.
 *
 * The WAKE_Q macro declares and initializes the list head.
 * wake_up_q() does NOT reinitialize the list; it's expected to be
 * called near the end of a function, where the fact that the queue is
 * not used again will be easy to see by inspection.
 *
 * Note that this can cause spurious wakeups. schedule() callers
 * must ensure the call is done inside a loop, confirming that the
 * wakeup condition has in fact occurred.
 */
struct wake_q_node {
	struct wake_q_node *next;
};

struct wake_q_head {
	struct wake_q_node *first;
	struct wake_q_node **lastp;
};

#define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)

#define WAKE_Q(name)					\
	struct wake_q_head name = { WAKE_Q_TAIL, &name.first }

extern void wake_q_add(struct wake_q_head *head,
		       struct task_struct *task);
extern void wake_up_q(struct wake_q_head *head);

974 975 976
/*
 * sched-domains (multiprocessor balancing) declarations:
 */
977
#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 */
982
#define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
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#define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
984
#define SD_SHARE_CPUCAPACITY	0x0080	/* Domain members share cpu power */
985
#define SD_SHARE_POWERDOMAIN	0x0100	/* Domain members share power domain */
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#define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
#define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
988
#define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
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#define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
990
#define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
991
#define SD_NUMA			0x4000	/* cross-node balancing */
992

993
#ifdef CONFIG_SCHED_SMT
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static inline int cpu_smt_flags(void)
995
{
996
	return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
997 998 999 1000
}
#endif

#ifdef CONFIG_SCHED_MC
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static inline int cpu_core_flags(void)
1002 1003 1004 1005 1006 1007
{
	return SD_SHARE_PKG_RESOURCES;
}
#endif

#ifdef CONFIG_NUMA
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static inline int cpu_numa_flags(void)
1009 1010 1011 1012
{
	return SD_NUMA;
}
#endif
1013

1014 1015 1016 1017 1018 1019 1020 1021
struct sched_domain_attr {
	int relax_domain_level;
};

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

1022 1023
extern int sched_domain_level_max;

1024 1025
struct sched_group;

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struct sched_domain {
	/* These fields must be setup */
	struct sched_domain *parent;	/* top domain must be null terminated */
1029
	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 nohz_idle;			/* NOHZ IDLE status */
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	int flags;			/* See SD_* */
1045
	int 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 */

1052
	/* idle_balance() stats */
1053
	u64 max_newidle_lb_cost;
1054
	unsigned long next_decay_max_lb_cost;
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#ifdef CONFIG_SCHEDSTATS
	/* load_balance() stats */
1058 1059 1060 1061 1062 1063 1064 1065
	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 */
1068 1069 1070
	unsigned int alb_count;
	unsigned int alb_failed;
	unsigned int alb_pushed;
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1072
	/* SD_BALANCE_EXEC stats */
1073 1074 1075
	unsigned int sbe_count;
	unsigned int sbe_balanced;
	unsigned int sbe_pushed;
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1077
	/* SD_BALANCE_FORK stats */
1078 1079 1080
	unsigned int sbf_count;
	unsigned int sbf_balanced;
	unsigned int sbf_pushed;
1081

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	/* try_to_wake_up() stats */
1083 1084 1085
	unsigned int ttwu_wake_remote;
	unsigned int ttwu_move_affine;
	unsigned int ttwu_move_balance;
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#endif
1087 1088 1089
#ifdef CONFIG_SCHED_DEBUG
	char *name;
#endif
1090 1091 1092 1093
	union {
		void *private;		/* used during construction */
		struct rcu_head rcu;	/* used during destruction */
	};
1094

1095
	unsigned int span_weight;
1096 1097 1098 1099 1100 1101 1102 1103
	/*
	 * 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)
	 */
	unsigned long span[0];
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};

1106 1107
static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
{
1108
	return to_cpumask(sd->span);
1109 1110
}

1111
extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1112
				    struct sched_domain_attr *dattr_new);
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1114 1115 1116 1117
/* 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);

1118 1119
bool cpus_share_cache(int this_cpu, int that_cpu);

1120
typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
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typedef int (*sched_domain_flags_f)(void);
1122 1123 1124 1125 1126 1127

#define SDTL_OVERLAP	0x01

struct sd_data {
	struct sched_domain **__percpu sd;
	struct sched_group **__percpu sg;
1128
	struct sched_group_capacity **__percpu sgc;
1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142
};

struct sched_domain_topology_level {
	sched_domain_mask_f mask;
	sched_domain_flags_f sd_flags;
	int		    flags;
	int		    numa_level;
	struct sd_data      data;
#ifdef CONFIG_SCHED_DEBUG
	char                *name;
#endif
};

extern void set_sched_topology(struct sched_domain_topology_level *tl);
1143
extern void wake_up_if_idle(int cpu);
1144 1145 1146 1147 1148 1149 1150

#ifdef CONFIG_SCHED_DEBUG
# define SD_INIT_NAME(type)		.name = #type
#else
# define SD_INIT_NAME(type)
#endif

1151
#else /* CONFIG_SMP */
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1153
struct sched_domain_attr;
1154

1155
static inline void
1156
partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1157 1158
			struct sched_domain_attr *dattr_new)
{
1159
}
1160 1161 1162 1163 1164 1165

static inline bool cpus_share_cache(int this_cpu, int that_cpu)
{
	return true;
}

1166
#endif	/* !CONFIG_SMP */
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1168

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struct io_context;			/* See blkdev.h */


1172
#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1173
extern void prefetch_stack(struct task_struct *t);
1174 1175 1176
#else
static inline void prefetch_stack(struct task_struct *t) { }
#endif
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struct audit_context;		/* See audit.c */
struct mempolicy;
1180
struct pipe_inode_info;
1181
struct uts_namespace;
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1183
struct load_weight {
1184 1185
	unsigned long weight;
	u32 inv_weight;
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1186 1187
};

1188 1189
/*
 * The load_avg/util_avg accumulates an infinite geometric series.
1190 1191 1192
 * 1) load_avg factors frequency scaling into the amount of time that a
 * sched_entity is runnable on a rq into its weight. For cfs_rq, it is the
 * aggregated such weights of all runnable and blocked sched_entities.
1193
 * 2) util_avg factors frequency and cpu scaling into the amount of time
1194 1195 1196 1197 1198 1199 1200 1201
 * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE].
 * For cfs_rq, it is the aggregated such times of all runnable and
 * blocked sched_entities.
 * The 64 bit load_sum can:
 * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with
 * the highest weight (=88761) always runnable, we should not overflow
 * 2) for entity, support any load.weight always runnable
 */
1202
struct sched_avg {
1203 1204 1205
	u64 last_update_time, load_sum;
	u32 util_sum, period_contrib;
	unsigned long load_avg, util_avg;
1206 1207
};

1208
#ifdef CONFIG_SCHEDSTATS
1209
struct sched_statistics {
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1210
	u64			wait_start;
1211
	u64			wait_max;
1212 1213
	u64			wait_count;
	u64			wait_sum;
1214 1215
	u64			iowait_count;
	u64			iowait_sum;
1216

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1217 1218
	u64			sleep_start;
	u64			sleep_max;
1219 1220 1221
	s64			sum_sleep_runtime;

	u64			block_start;
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1222 1223
	u64			block_max;
	u64			exec_max;
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1224
	u64			slice_max;
1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240

	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;
1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258
};
#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;
1259 1260
#endif

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#ifdef CONFIG_FAIR_GROUP_SCHED
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1262
	int			depth;
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1263 1264 1265 1266 1267 1268
	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
1269

1270
#ifdef CONFIG_SMP
1271
	/* Per entity load average tracking */
1272 1273
	struct sched_avg	avg;
#endif
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1274
};
1275

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1276 1277
struct sched_rt_entity {
	struct list_head run_list;
1278
	unsigned long timeout;
1279
	unsigned long watchdog_stamp;
1280
	unsigned int time_slice;
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1281

1282
	struct sched_rt_entity *back;
1283
#ifdef CONFIG_RT_GROUP_SCHED
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1284 1285 1286 1287 1288 1289
	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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1290 1291
};

1292 1293 1294 1295 1296
struct sched_dl_entity {
	struct rb_node	rb_node;

	/*
	 * Original scheduling parameters. Copied here from sched_attr
1297 1298
	 * during sched_setattr(), they will remain the same until
	 * the next sched_setattr().
1299 1300 1301
	 */
	u64 dl_runtime;		/* maximum runtime for each instance	*/
	u64 dl_deadline;	/* relative deadline of each instance	*/
1302
	u64 dl_period;		/* separation of two instances (period) */
1303
	u64 dl_bw;		/* dl_runtime / dl_deadline		*/
1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323

	/*
	 * Actual scheduling parameters. Initialized with the values above,
	 * they are continously updated during task execution. Note that
	 * the remaining runtime could be < 0 in case we are in overrun.
	 */
	s64 runtime;		/* remaining runtime for this instance	*/
	u64 deadline;		/* absolute deadline for this instance	*/
	unsigned int flags;	/* specifying the scheduler behaviour	*/

	/*
	 * Some bool flags:
	 *
	 * @dl_throttled tells if we exhausted the runtime. If so, the
	 * task has to wait for a replenishment to be performed at the
	 * next firing of dl_timer.
	 *
	 * @dl_new tells if a new instance arrived. If so we must
	 * start executing it with full runtime and reset its absolute
	 * deadline;
1324 1325 1326
	 *
	 * @dl_boosted tells if we are boosted due to DI. If so we are
	 * outside bandwidth enforcement mechanism (but only until we
1327 1328 1329 1330
	 * exit the critical section);
	 *
	 * @dl_yielded tells if task gave up the cpu before consuming
	 * all its available runtime during the last job.
1331
	 */
1332
	int dl_throttled, dl_new, dl_boosted, dl_yielded;
1333 1334 1335 1336 1337 1338 1339

	/*
	 * Bandwidth enforcement timer. Each -deadline task has its
	 * own bandwidth to be enforced, thus we need one timer per task.
	 */
	struct hrtimer dl_timer;
};
1340

1341 1342
union rcu_special {
	struct {
1343 1344 1345 1346 1347 1348
		u8 blocked;
		u8 need_qs;
		u8 exp_need_qs;
		u8 pad;	/* Otherwise the compiler can store garbage here. */
	} b; /* Bits. */
	u32 s; /* Set of bits. */
1349
};
1350 1351
struct rcu_node;

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1352 1353 1354
enum perf_event_task_context {
	perf_invalid_context = -1,
	perf_hw_context = 0,
1355
	perf_sw_context,
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1356 1357 1358
	perf_nr_task_contexts,
};

1359 1360 1361 1362 1363 1364 1365 1366 1367 1368
/* Track pages that require TLB flushes */
struct tlbflush_unmap_batch {
	/*
	 * Each bit set is a CPU that potentially has a TLB entry for one of
	 * the PFNs being flushed. See set_tlb_ubc_flush_pending().
	 */
	struct cpumask cpumask;

	/* True if any bit in cpumask is set */
	bool flush_required;
1369 1370 1371 1372 1373 1374 1375

	/*
	 * If true then the PTE was dirty when unmapped. The entry must be
	 * flushed before IO is initiated or a stale TLB entry potentially
	 * allows an update without redirtying the page.
	 */
	bool writable;
1376 1377
};

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struct task_struct {
	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
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1380
	void *stack;
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1381
	atomic_t usage;
1382 1383
	unsigned int flags;	/* per process flags, defined below */
	unsigned int ptrace;
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1384

1385
#ifdef CONFIG_SMP
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1386
	struct llist_node wake_entry;
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1387
	int on_cpu;
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1388
	unsigned int wakee_flips;
1389
	unsigned long wakee_flip_decay_ts;
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1390
	struct task_struct *last_wakee;
1391 1392

	int wake_cpu;
1393
#endif
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1394
	int on_rq;
1395

1396
	int prio, static_prio, normal_prio;
1397
	unsigned int rt_priority;
1398
	const struct sched_class *sched_class;
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	struct sched_entity se;
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1400
	struct sched_rt_entity rt;
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1401 1402 1403
#ifdef CONFIG_CGROUP_SCHED
	struct task_group *sched_task_group;
#endif
1404
	struct sched_dl_entity dl;
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1406 1407 1408 1409 1410
#ifdef CONFIG_PREEMPT_NOTIFIERS
	/* list of struct preempt_notifier: */
	struct hlist_head preempt_notifiers;
#endif

1411
#ifdef CONFIG_BLK_DEV_IO_TRACE
1412
	unsigned int btrace_seq;
1413
#endif
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1414

1415
	unsigned int policy;
1416
	int nr_cpus_allowed;
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1417 1418
	cpumask_t cpus_allowed;

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1419
#ifdef CONFIG_PREEMPT_RCU
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1420
	int rcu_read_lock_nesting;
1421
	union rcu_special rcu_read_unlock_special;
1422
	struct list_head rcu_node_entry;
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1423
	struct rcu_node *rcu_blocked_node;
1424
#endif /* #ifdef CONFIG_PREEMPT_RCU */
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1425 1426 1427 1428
#ifdef CONFIG_TASKS_RCU
	unsigned long rcu_tasks_nvcsw;
	bool rcu_tasks_holdout;
	struct list_head rcu_tasks_holdout_list;
1429
	int rcu_tasks_idle_cpu;
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1430
#endif /* #ifdef CONFIG_TASKS_RCU */
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1431

1432
#ifdef CONFIG_SCHED_INFO
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1433 1434 1435 1436
	struct sched_info sched_info;
#endif

	struct list_head tasks;
1437
#ifdef CONFIG_SMP
1438
	struct plist_node pushable_tasks;
1439
	struct rb_node pushable_dl_tasks;
1440
#endif
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1441 1442

	struct mm_struct *mm, *active_mm;
D
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1443 1444 1445
	/* per-thread vma caching */
	u32 vmacache_seqnum;
	struct vm_area_struct *vmacache[VMACACHE_SIZE];
1446 1447 1448
#if defined(SPLIT_RSS_COUNTING)
	struct task_rss_stat	rss_stat;
#endif
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1449
/* task state */
1450
	int exit_state;
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1451 1452
	int exit_code, exit_signal;
	int pdeath_signal;  /*  The signal sent when the parent dies  */
1453
	unsigned long jobctl;	/* JOBCTL_*, siglock protected */
1454 1455

	/* Used for emulating ABI behavior of previous Linux versions */
1456
	unsigned int personality;
1457

1458 1459
	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
				 * execve */
1460 1461
	unsigned in_iowait:1;

1462 1463
	/* Revert to default priority/policy when forking */
	unsigned sched_reset_on_fork:1;
1464
	unsigned sched_contributes_to_load:1;
1465
	unsigned sched_migrated:1;
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1466 1467 1468
#ifdef CONFIG_MEMCG
	unsigned memcg_may_oom:1;
#endif
1469 1470 1471
#ifdef CONFIG_MEMCG_KMEM
	unsigned memcg_kmem_skip_account:1;
#endif
1472 1473 1474
#ifdef CONFIG_COMPAT_BRK
	unsigned brk_randomized:1;
#endif
1475

1476 1477
	unsigned long atomic_flags; /* Flags needing atomic access. */

1478 1479
	struct restart_block restart_block;

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1480 1481
	pid_t pid;
	pid_t tgid;
1482

1483
#ifdef CONFIG_CC_STACKPROTECTOR
1484 1485
	/* Canary value for the -fstack-protector gcc feature */
	unsigned long stack_canary;
1486
#endif
1487
	/*
L
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1488
	 * pointers to (original) parent process, youngest child, younger sibling,
1489
	 * older sibling, respectively.  (p->father can be replaced with
R
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1490
	 * p->real_parent->pid)
L
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1491
	 */
1492 1493
	struct task_struct __rcu *real_parent; /* real parent process */
	struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
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1494
	/*
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1495
	 * children/sibling forms the list of my natural children
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1496 1497 1498 1499 1500
	 */
	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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1501 1502 1503 1504 1505 1506 1507 1508
	/*
	 * 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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1509
	/* PID/PID hash table linkage. */
1510
	struct pid_link pids[PIDTYPE_MAX];
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1511
	struct list_head thread_group;
1512
	struct list_head thread_node;
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1513 1514 1515 1516 1517

	struct completion *vfork_done;		/* for vfork() */
	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */

1518
	cputime_t utime, stime, utimescaled, stimescaled;
1519
	cputime_t gtime;
1520
	struct prev_cputime prev_cputime;
1521 1522 1523 1524 1525 1526 1527 1528
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
	seqlock_t vtime_seqlock;
	unsigned long long vtime_snap;
	enum {
		VTIME_SLEEPING = 0,
		VTIME_USER,
		VTIME_SYS,
	} vtime_snap_whence;
1529
#endif
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1530
	unsigned long nvcsw, nivcsw; /* context switch counts */
1531
	u64 start_time;		/* monotonic time in nsec */
1532
	u64 real_start_time;	/* boot based time in nsec */
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1533 1534 1535
/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
	unsigned long min_flt, maj_flt;

1536
	struct task_cputime cputime_expires;
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1537 1538 1539
	struct list_head cpu_timers[3];

/* process credentials */
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1540
	const struct cred __rcu *real_cred; /* objective and real subjective task
1541
					 * credentials (COW) */
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1542
	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1543
					 * credentials (COW) */
1544 1545 1546
	char comm[TASK_COMM_LEN]; /* executable name excluding path
				     - access with [gs]et_task_comm (which lock
				       it with task_lock())
1547
				     - initialized normally by setup_new_exec */
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1548
/* file system info */
1549
	struct nameidata *nameidata;
1550
#ifdef CONFIG_SYSVIPC
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1551 1552
/* ipc stuff */
	struct sysv_sem sysvsem;
1553
	struct sysv_shm sysvshm;
1554
#endif
1555
#ifdef CONFIG_DETECT_HUNG_TASK
1556 1557 1558
/* hung task detection */
	unsigned long last_switch_count;
#endif
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1559 1560 1561 1562
/* filesystem information */
	struct fs_struct *fs;
/* open file information */
	struct files_struct *files;
1563
/* namespaces */
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1564
	struct nsproxy *nsproxy;
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1565 1566 1567 1568 1569
/* signal handlers */
	struct signal_struct *signal;
	struct sighand_struct *sighand;

	sigset_t blocked, real_blocked;
1570
	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;
1575

1576
	struct callback_head *task_works;
1577

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1578
	struct audit_context *audit_context;
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1579
#ifdef CONFIG_AUDITSYSCALL
1580
	kuid_t loginuid;
1581
	unsigned int sessionid;
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1582
#endif
1583
	struct seccomp seccomp;
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1584 1585 1586 1587

/* Thread group tracking */
   	u32 parent_exec_id;
   	u32 self_exec_id;
1588 1589
/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
 * mempolicy */
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1590 1591
	spinlock_t alloc_lock;

1592
	/* Protection of the PI data structures: */
1593
	raw_spinlock_t pi_lock;
1594

1595 1596
	struct wake_q_node wake_q;

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#ifdef CONFIG_RT_MUTEXES
	/* PI waiters blocked on a rt_mutex held by this task */
1599 1600
	struct rb_root pi_waiters;
	struct rb_node *pi_waiters_leftmost;
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1601 1602 1603 1604
	/* Deadlock detection and priority inheritance handling */
	struct rt_mutex_waiter *pi_blocked_on;
#endif

1605 1606 1607 1608
#ifdef CONFIG_DEBUG_MUTEXES
	/* mutex deadlock detection */
	struct mutex_waiter *blocked_on;
#endif
1609 1610 1611 1612
#ifdef CONFIG_TRACE_IRQFLAGS
	unsigned int irq_events;
	unsigned long hardirq_enable_ip;
	unsigned long hardirq_disable_ip;
1613
	unsigned int hardirq_enable_event;
1614
	unsigned int hardirq_disable_event;
1615 1616
	int hardirqs_enabled;
	int hardirq_context;
1617 1618
	unsigned long softirq_disable_ip;
	unsigned long softirq_enable_ip;
1619
	unsigned int softirq_disable_event;
1620
	unsigned int softirq_enable_event;
1621
	int softirqs_enabled;
1622 1623
	int softirq_context;
#endif
I
Ingo Molnar 已提交
1624
#ifdef CONFIG_LOCKDEP
1625
# define MAX_LOCK_DEPTH 48UL
I
Ingo Molnar 已提交
1626 1627 1628
	u64 curr_chain_key;
	int lockdep_depth;
	unsigned int lockdep_recursion;
1629
	struct held_lock held_locks[MAX_LOCK_DEPTH];
1630
	gfp_t lockdep_reclaim_gfp;
I
Ingo Molnar 已提交
1631
#endif
1632

L
Linus Torvalds 已提交
1633 1634 1635
/* journalling filesystem info */
	void *journal_info;

1636
/* stacked block device info */
1637
	struct bio_list *bio_list;
1638

1639 1640 1641 1642 1643
#ifdef CONFIG_BLOCK
/* stack plugging */
	struct blk_plug *plug;
#endif

L
Linus Torvalds 已提交
1644 1645 1646 1647 1648 1649 1650 1651 1652
/* 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.  */
1653
	struct task_io_accounting ioac;
1654
#if defined(CONFIG_TASK_XACCT)
L
Linus Torvalds 已提交
1655 1656
	u64 acct_rss_mem1;	/* accumulated rss usage */
	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1657
	cputime_t acct_timexpd;	/* stime + utime since last update */
L
Linus Torvalds 已提交
1658 1659
#endif
#ifdef CONFIG_CPUSETS
1660
	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1661
	seqcount_t mems_allowed_seq;	/* Seqence no to catch updates */
1662
	int cpuset_mem_spread_rotor;
1663
	int cpuset_slab_spread_rotor;
L
Linus Torvalds 已提交
1664
#endif
1665
#ifdef CONFIG_CGROUPS
1666
	/* Control Group info protected by css_set_lock */
A
Arnd Bergmann 已提交
1667
	struct css_set __rcu *cgroups;
1668 1669
	/* cg_list protected by css_set_lock and tsk->alloc_lock */
	struct list_head cg_list;
1670
#endif
1671
#ifdef CONFIG_FUTEX
1672
	struct robust_list_head __user *robust_list;
1673 1674 1675
#ifdef CONFIG_COMPAT
	struct compat_robust_list_head __user *compat_robust_list;
#endif
1676 1677
	struct list_head pi_state_list;
	struct futex_pi_state *pi_state_cache;
1678
#endif
1679
#ifdef CONFIG_PERF_EVENTS
P
Peter Zijlstra 已提交
1680
	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1681 1682
	struct mutex perf_event_mutex;
	struct list_head perf_event_list;
1683
#endif
1684 1685 1686
#ifdef CONFIG_DEBUG_PREEMPT
	unsigned long preempt_disable_ip;
#endif
1687
#ifdef CONFIG_NUMA
1688
	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1689
	short il_next;
1690
	short pref_node_fork;
1691
#endif
1692 1693 1694
#ifdef CONFIG_NUMA_BALANCING
	int numa_scan_seq;
	unsigned int numa_scan_period;
1695
	unsigned int numa_scan_period_max;
1696
	int numa_preferred_nid;
1697
	unsigned long numa_migrate_retry;
1698
	u64 node_stamp;			/* migration stamp  */
1699 1700
	u64 last_task_numa_placement;
	u64 last_sum_exec_runtime;
1701
	struct callback_head numa_work;
1702

1703 1704 1705
	struct list_head numa_entry;
	struct numa_group *numa_group;

1706
	/*
1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718
	 * numa_faults is an array split into four regions:
	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
	 * in this precise order.
	 *
	 * faults_memory: Exponential decaying average of faults on a per-node
	 * basis. Scheduling placement decisions are made based on these
	 * counts. The values remain static for the duration of a PTE scan.
	 * faults_cpu: Track the nodes the process was running on when a NUMA
	 * hinting fault was incurred.
	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
	 * during the current scan window. When the scan completes, the counts
	 * in faults_memory and faults_cpu decay and these values are copied.
1719
	 */
1720
	unsigned long *numa_faults;
1721
	unsigned long total_numa_faults;
1722

1723 1724
	/*
	 * numa_faults_locality tracks if faults recorded during the last
1725 1726 1727
	 * scan window were remote/local or failed to migrate. The task scan
	 * period is adapted based on the locality of the faults with different
	 * weights depending on whether they were shared or private faults
1728
	 */
1729
	unsigned long numa_faults_locality[3];
1730

I
Ingo Molnar 已提交
1731
	unsigned long numa_pages_migrated;
1732 1733
#endif /* CONFIG_NUMA_BALANCING */

1734 1735 1736 1737
#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
	struct tlbflush_unmap_batch tlb_ubc;
#endif

I
Ingo Molnar 已提交
1738
	struct rcu_head rcu;
1739 1740 1741 1742 1743

	/*
	 * cache last used pipe for splice
	 */
	struct pipe_inode_info *splice_pipe;
1744 1745 1746

	struct page_frag task_frag;

1747 1748
#ifdef	CONFIG_TASK_DELAY_ACCT
	struct task_delay_info *delays;
1749 1750 1751
#endif
#ifdef CONFIG_FAULT_INJECTION
	int make_it_fail;
1752
#endif
1753 1754 1755 1756 1757 1758
	/*
	 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
	 * balance_dirty_pages() for some dirty throttling pause
	 */
	int nr_dirtied;
	int nr_dirtied_pause;
1759
	unsigned long dirty_paused_when; /* start of a write-and-pause period */
1760

A
Arjan van de Ven 已提交
1761 1762 1763 1764
#ifdef CONFIG_LATENCYTOP
	int latency_record_count;
	struct latency_record latency_record[LT_SAVECOUNT];
#endif
1765 1766 1767 1768 1769 1770
	/*
	 * 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;
1771

1772 1773 1774
#ifdef CONFIG_KASAN
	unsigned int kasan_depth;
#endif
1775
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
D
Daniel Mack 已提交
1776
	/* Index of current stored address in ret_stack */
1777 1778 1779
	int curr_ret_stack;
	/* Stack of return addresses for return function tracing */
	struct ftrace_ret_stack	*ret_stack;
1780 1781
	/* time stamp for last schedule */
	unsigned long long ftrace_timestamp;
1782 1783 1784 1785 1786
	/*
	 * Number of functions that haven't been traced
	 * because of depth overrun.
	 */
	atomic_t trace_overrun;
1787 1788
	/* Pause for the tracing */
	atomic_t tracing_graph_pause;
1789
#endif
1790 1791 1792
#ifdef CONFIG_TRACING
	/* state flags for use by tracers */
	unsigned long trace;
1793
	/* bitmask and counter of trace recursion */
1794 1795
	unsigned long trace_recursion;
#endif /* CONFIG_TRACING */
1796
#ifdef CONFIG_MEMCG
T
Tejun Heo 已提交
1797 1798 1799
	struct mem_cgroup *memcg_in_oom;
	gfp_t memcg_oom_gfp_mask;
	int memcg_oom_order;
1800 1801 1802

	/* number of pages to reclaim on returning to userland */
	unsigned int memcg_nr_pages_over_high;
1803
#endif
1804 1805 1806
#ifdef CONFIG_UPROBES
	struct uprobe_task *utask;
#endif
K
Kent Overstreet 已提交
1807 1808 1809 1810
#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
	unsigned int	sequential_io;
	unsigned int	sequential_io_avg;
#endif
P
Peter Zijlstra 已提交
1811 1812 1813
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
	unsigned long	task_state_change;
#endif
1814
	int pagefault_disabled;
1815 1816 1817 1818 1819 1820 1821 1822
/* CPU-specific state of this task */
	struct thread_struct thread;
/*
 * WARNING: on x86, 'thread_struct' contains a variable-sized
 * structure.  It *MUST* be at the end of 'task_struct'.
 *
 * Do not put anything below here!
 */
L
Linus Torvalds 已提交
1823 1824
};

1825 1826 1827 1828 1829
#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
extern int arch_task_struct_size __read_mostly;
#else
# define arch_task_struct_size (sizeof(struct task_struct))
#endif
1830

1831
/* Future-safe accessor for struct task_struct's cpus_allowed. */
1832
#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1833

1834 1835
#define TNF_MIGRATED	0x01
#define TNF_NO_GROUP	0x02
1836
#define TNF_SHARED	0x04
1837
#define TNF_FAULT_LOCAL	0x08
1838
#define TNF_MIGRATE_FAIL 0x10
1839

1840
#ifdef CONFIG_NUMA_BALANCING
1841
extern void task_numa_fault(int last_node, int node, int pages, int flags);
1842
extern pid_t task_numa_group_id(struct task_struct *p);
1843
extern void set_numabalancing_state(bool enabled);
1844
extern void task_numa_free(struct task_struct *p);
1845 1846
extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
					int src_nid, int dst_cpu);
1847
#else
1848
static inline void task_numa_fault(int last_node, int node, int pages,
1849
				   int flags)
1850 1851
{
}
1852 1853 1854 1855
static inline pid_t task_numa_group_id(struct task_struct *p)
{
	return 0;
}
1856 1857 1858
static inline void set_numabalancing_state(bool enabled)
{
}
1859 1860 1861
static inline void task_numa_free(struct task_struct *p)
{
}
1862 1863 1864 1865 1866
static inline bool should_numa_migrate_memory(struct task_struct *p,
				struct page *page, int src_nid, int dst_cpu)
{
	return true;
}
1867 1868
#endif

A
Alexey Dobriyan 已提交
1869
static inline struct pid *task_pid(struct task_struct *task)
1870 1871 1872 1873
{
	return task->pids[PIDTYPE_PID].pid;
}

A
Alexey Dobriyan 已提交
1874
static inline struct pid *task_tgid(struct task_struct *task)
1875 1876 1877 1878
{
	return task->group_leader->pids[PIDTYPE_PID].pid;
}

1879 1880 1881 1882 1883
/*
 * 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.
 */
A
Alexey Dobriyan 已提交
1884
static inline struct pid *task_pgrp(struct task_struct *task)
1885 1886 1887 1888
{
	return task->group_leader->pids[PIDTYPE_PGID].pid;
}

A
Alexey Dobriyan 已提交
1889
static inline struct pid *task_session(struct task_struct *task)
1890 1891 1892 1893
{
	return task->group_leader->pids[PIDTYPE_SID].pid;
}

1894 1895 1896 1897 1898 1899 1900
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;
E
Eric W. Biederman 已提交
1901 1902
 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
 *                     current.
1903 1904 1905 1906 1907 1908
 * 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
 */
1909 1910
pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
			struct pid_namespace *ns);
1911

A
Alexey Dobriyan 已提交
1912
static inline pid_t task_pid_nr(struct task_struct *tsk)
1913 1914 1915 1916
{
	return tsk->pid;
}

1917 1918 1919 1920 1921
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);
}
1922 1923 1924

static inline pid_t task_pid_vnr(struct task_struct *tsk)
{
1925
	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1926 1927 1928
}


A
Alexey Dobriyan 已提交
1929
static inline pid_t task_tgid_nr(struct task_struct *tsk)
1930 1931 1932 1933
{
	return tsk->tgid;
}

1934
pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1935 1936 1937 1938 1939 1940 1941

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


1942
static inline int pid_alive(const struct task_struct *p);
1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959
static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
{
	pid_t pid = 0;

	rcu_read_lock();
	if (pid_alive(tsk))
		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
	rcu_read_unlock();

	return pid;
}

static inline pid_t task_ppid_nr(const struct task_struct *tsk)
{
	return task_ppid_nr_ns(tsk, &init_pid_ns);
}

1960 1961
static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
1962
{
1963
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1964 1965 1966 1967
}

static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
{
1968
	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1969 1970 1971
}


1972 1973
static inline pid_t task_session_nr_ns(struct task_struct *tsk,
					struct pid_namespace *ns)
1974
{
1975
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1976 1977 1978 1979
}

static inline pid_t task_session_vnr(struct task_struct *tsk)
{
1980
	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1981 1982
}

1983 1984 1985 1986 1987
/* obsolete, do not use */
static inline pid_t task_pgrp_nr(struct task_struct *tsk)
{
	return task_pgrp_nr_ns(tsk, &init_pid_ns);
}
1988

L
Linus Torvalds 已提交
1989 1990 1991 1992 1993 1994 1995
/**
 * 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.
1996 1997
 *
 * Return: 1 if the process is alive. 0 otherwise.
L
Linus Torvalds 已提交
1998
 */
1999
static inline int pid_alive(const struct task_struct *p)
L
Linus Torvalds 已提交
2000
{
2001
	return p->pids[PIDTYPE_PID].pid != NULL;
L
Linus Torvalds 已提交
2002 2003
}

2004
/**
2005 2006
 * is_global_init - check if a task structure is init. Since init
 * is free to have sub-threads we need to check tgid.
2007 2008 2009
 * @tsk: Task structure to be checked.
 *
 * Check if a task structure is the first user space task the kernel created.
2010 2011
 *
 * Return: 1 if the task structure is init. 0 otherwise.
2012
 */
A
Alexey Dobriyan 已提交
2013
static inline int is_global_init(struct task_struct *tsk)
2014
{
2015
	return task_tgid_nr(tsk) == 1;
2016
}
2017

2018 2019
extern struct pid *cad_pid;

L
Linus Torvalds 已提交
2020 2021
extern void free_task(struct task_struct *tsk);
#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
I
Ingo Molnar 已提交
2022

2023
extern void __put_task_struct(struct task_struct *t);
I
Ingo Molnar 已提交
2024 2025 2026 2027

static inline void put_task_struct(struct task_struct *t)
{
	if (atomic_dec_and_test(&t->usage))
2028
		__put_task_struct(t);
I
Ingo Molnar 已提交
2029
}
L
Linus Torvalds 已提交
2030

2031 2032 2033 2034 2035 2036 2037
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
extern void task_cputime(struct task_struct *t,
			 cputime_t *utime, cputime_t *stime);
extern void task_cputime_scaled(struct task_struct *t,
				cputime_t *utimescaled, cputime_t *stimescaled);
extern cputime_t task_gtime(struct task_struct *t);
#else
2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055
static inline void task_cputime(struct task_struct *t,
				cputime_t *utime, cputime_t *stime)
{
	if (utime)
		*utime = t->utime;
	if (stime)
		*stime = t->stime;
}

static inline void task_cputime_scaled(struct task_struct *t,
				       cputime_t *utimescaled,
				       cputime_t *stimescaled)
{
	if (utimescaled)
		*utimescaled = t->utimescaled;
	if (stimescaled)
		*stimescaled = t->stimescaled;
}
2056 2057 2058 2059 2060 2061

static inline cputime_t task_gtime(struct task_struct *t)
{
	return t->gtime;
}
#endif
2062 2063
extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2064

L
Linus Torvalds 已提交
2065 2066 2067 2068
/*
 * Per process flags
 */
#define PF_EXITING	0x00000004	/* getting shut down */
2069
#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
2070
#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
T
Tejun Heo 已提交
2071
#define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
L
Linus Torvalds 已提交
2072
#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
2073
#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
L
Linus Torvalds 已提交
2074 2075 2076 2077
#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 */
2078
#define PF_NPROC_EXCEEDED 0x00001000	/* set_user noticed that RLIMIT_NPROC was exceeded */
L
Linus Torvalds 已提交
2079
#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
2080
#define PF_USED_ASYNC	0x00004000	/* used async_schedule*(), used by module init */
L
Linus Torvalds 已提交
2081 2082 2083 2084
#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 */
2085
#define PF_MEMALLOC_NOIO 0x00080000	/* Allocating memory without IO involved */
L
Linus Torvalds 已提交
2086
#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
2087
#define PF_KTHREAD	0x00200000	/* I am a kernel thread */
J
Jens Axboe 已提交
2088 2089
#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
2090
#define PF_NO_SETAFFINITY 0x04000000	/* Userland is not allowed to meddle with cpus_allowed */
2091
#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
2092
#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
2093
#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
2094
#define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
L
Linus Torvalds 已提交
2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120

/*
 * 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)

2121 2122 2123
/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
 * __GFP_FS is also cleared as it implies __GFP_IO.
 */
2124 2125 2126
static inline gfp_t memalloc_noio_flags(gfp_t flags)
{
	if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2127
		flags &= ~(__GFP_IO | __GFP_FS);
2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142
	return flags;
}

static inline unsigned int memalloc_noio_save(void)
{
	unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
	current->flags |= PF_MEMALLOC_NOIO;
	return flags;
}

static inline void memalloc_noio_restore(unsigned int flags)
{
	current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
}

2143
/* Per-process atomic flags. */
2144
#define PFA_NO_NEW_PRIVS 0	/* May not gain new privileges. */
2145 2146 2147
#define PFA_SPREAD_PAGE  1      /* Spread page cache over cpuset */
#define PFA_SPREAD_SLAB  2      /* Spread some slab caches over cpuset */

2148

2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160
#define TASK_PFA_TEST(name, func)					\
	static inline bool task_##func(struct task_struct *p)		\
	{ return test_bit(PFA_##name, &p->atomic_flags); }
#define TASK_PFA_SET(name, func)					\
	static inline void task_set_##func(struct task_struct *p)	\
	{ set_bit(PFA_##name, &p->atomic_flags); }
#define TASK_PFA_CLEAR(name, func)					\
	static inline void task_clear_##func(struct task_struct *p)	\
	{ clear_bit(PFA_##name, &p->atomic_flags); }

TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2161

2162 2163 2164 2165 2166 2167 2168
TASK_PFA_TEST(SPREAD_PAGE, spread_page)
TASK_PFA_SET(SPREAD_PAGE, spread_page)
TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)

TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
TASK_PFA_SET(SPREAD_SLAB, spread_slab)
TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2169

2170
/*
2171
 * task->jobctl flags
2172
 */
2173
#define JOBCTL_STOP_SIGMASK	0xffff	/* signr of the last group stop */
2174

2175 2176 2177
#define JOBCTL_STOP_DEQUEUED_BIT 16	/* stop signal dequeued */
#define JOBCTL_STOP_PENDING_BIT	17	/* task should stop for group stop */
#define JOBCTL_STOP_CONSUME_BIT	18	/* consume group stop count */
2178
#define JOBCTL_TRAP_STOP_BIT	19	/* trap for STOP */
2179
#define JOBCTL_TRAP_NOTIFY_BIT	20	/* trap for NOTIFY */
2180
#define JOBCTL_TRAPPING_BIT	21	/* switching to TRACED */
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Tejun Heo 已提交
2181
#define JOBCTL_LISTENING_BIT	22	/* ptracer is listening for events */
2182

2183 2184 2185 2186 2187 2188 2189
#define JOBCTL_STOP_DEQUEUED	(1UL << JOBCTL_STOP_DEQUEUED_BIT)
#define JOBCTL_STOP_PENDING	(1UL << JOBCTL_STOP_PENDING_BIT)
#define JOBCTL_STOP_CONSUME	(1UL << JOBCTL_STOP_CONSUME_BIT)
#define JOBCTL_TRAP_STOP	(1UL << JOBCTL_TRAP_STOP_BIT)
#define JOBCTL_TRAP_NOTIFY	(1UL << JOBCTL_TRAP_NOTIFY_BIT)
#define JOBCTL_TRAPPING		(1UL << JOBCTL_TRAPPING_BIT)
#define JOBCTL_LISTENING	(1UL << JOBCTL_LISTENING_BIT)
2190

2191
#define JOBCTL_TRAP_MASK	(JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2192
#define JOBCTL_PENDING_MASK	(JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2193

2194
extern bool task_set_jobctl_pending(struct task_struct *task,
2195
				    unsigned long mask);
2196
extern void task_clear_jobctl_trapping(struct task_struct *task);
2197
extern void task_clear_jobctl_pending(struct task_struct *task,
2198
				      unsigned long mask);
2199

2200 2201
static inline void rcu_copy_process(struct task_struct *p)
{
P
Paul E. McKenney 已提交
2202
#ifdef CONFIG_PREEMPT_RCU
2203
	p->rcu_read_lock_nesting = 0;
2204
	p->rcu_read_unlock_special.s = 0;
2205
	p->rcu_blocked_node = NULL;
2206
	INIT_LIST_HEAD(&p->rcu_node_entry);
P
Paul E. McKenney 已提交
2207 2208 2209 2210
#endif /* #ifdef CONFIG_PREEMPT_RCU */
#ifdef CONFIG_TASKS_RCU
	p->rcu_tasks_holdout = false;
	INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2211
	p->rcu_tasks_idle_cpu = -1;
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Paul E. McKenney 已提交
2212
#endif /* #ifdef CONFIG_TASKS_RCU */
2213 2214
}

2215 2216 2217 2218 2219 2220 2221
static inline void tsk_restore_flags(struct task_struct *task,
				unsigned long orig_flags, unsigned long flags)
{
	task->flags &= ~flags;
	task->flags |= orig_flags & flags;
}

2222 2223
extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
				     const struct cpumask *trial);
2224 2225
extern int task_can_attach(struct task_struct *p,
			   const struct cpumask *cs_cpus_allowed);
L
Linus Torvalds 已提交
2226
#ifdef CONFIG_SMP
2227 2228 2229
extern void do_set_cpus_allowed(struct task_struct *p,
			       const struct cpumask *new_mask);

2230
extern int set_cpus_allowed_ptr(struct task_struct *p,
2231
				const struct cpumask *new_mask);
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2232
#else
2233 2234 2235 2236
static inline void do_set_cpus_allowed(struct task_struct *p,
				      const struct cpumask *new_mask)
{
}
2237
static inline int set_cpus_allowed_ptr(struct task_struct *p,
2238
				       const struct cpumask *new_mask)
L
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2239
{
2240
	if (!cpumask_test_cpu(0, new_mask))
L
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2241 2242 2243 2244
		return -EINVAL;
	return 0;
}
#endif
2245

2246
#ifdef CONFIG_NO_HZ_COMMON
2247 2248 2249 2250 2251
void calc_load_enter_idle(void);
void calc_load_exit_idle(void);
#else
static inline void calc_load_enter_idle(void) { }
static inline void calc_load_exit_idle(void) { }
2252
#endif /* CONFIG_NO_HZ_COMMON */
2253

2254
/*
2255 2256 2257 2258 2259 2260
 * Do not use outside of architecture code which knows its limitations.
 *
 * sched_clock() has no promise of monotonicity or bounded drift between
 * CPUs, use (which you should not) requires disabling IRQs.
 *
 * Please use one of the three interfaces below.
2261
 */
2262
extern unsigned long long notrace sched_clock(void);
2263
/*
2264
 * See the comment in kernel/sched/clock.c
2265 2266 2267
 */
extern u64 cpu_clock(int cpu);
extern u64 local_clock(void);
2268
extern u64 running_clock(void);
2269 2270
extern u64 sched_clock_cpu(int cpu);

2271

2272
extern void sched_clock_init(void);
2273

2274
#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286
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
2287 2288 2289 2290 2291 2292
/*
 * 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:
 */
2293 2294 2295
extern int sched_clock_stable(void);
extern void set_sched_clock_stable(void);
extern void clear_sched_clock_stable(void);
2296

2297 2298 2299 2300 2301
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

2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
/*
 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
 * The reason for this explicit opt-in is not to have perf penalty with
 * slow sched_clocks.
 */
extern void enable_sched_clock_irqtime(void);
extern void disable_sched_clock_irqtime(void);
#else
static inline void enable_sched_clock_irqtime(void) {}
static inline void disable_sched_clock_irqtime(void) {}
#endif

2315
extern unsigned long long
2316
task_sched_runtime(struct task_struct *task);
L
Linus Torvalds 已提交
2317 2318 2319 2320 2321 2322 2323 2324

/* sched_exec is called by processes performing an exec */
#ifdef CONFIG_SMP
extern void sched_exec(void);
#else
#define sched_exec()   {}
#endif

2325 2326
extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2327

L
Linus Torvalds 已提交
2328 2329 2330 2331 2332 2333
#ifdef CONFIG_HOTPLUG_CPU
extern void idle_task_exit(void);
#else
static inline void idle_task_exit(void) {}
#endif

2334
#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2335
extern void wake_up_nohz_cpu(int cpu);
2336
#else
2337
static inline void wake_up_nohz_cpu(int cpu) { }
2338 2339
#endif

2340 2341
#ifdef CONFIG_NO_HZ_FULL
extern bool sched_can_stop_tick(void);
2342
extern u64 scheduler_tick_max_deferment(void);
2343 2344
#else
static inline bool sched_can_stop_tick(void) { return false; }
2345 2346
#endif

2347 2348 2349 2350 2351 2352 2353
#ifdef CONFIG_SCHED_AUTOGROUP
extern void sched_autogroup_create_attach(struct task_struct *p);
extern void sched_autogroup_detach(struct task_struct *p);
extern void sched_autogroup_fork(struct signal_struct *sig);
extern void sched_autogroup_exit(struct signal_struct *sig);
#ifdef CONFIG_PROC_FS
extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2354
extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2355 2356 2357 2358 2359 2360 2361 2362
#endif
#else
static inline void sched_autogroup_create_attach(struct task_struct *p) { }
static inline void sched_autogroup_detach(struct task_struct *p) { }
static inline void sched_autogroup_fork(struct signal_struct *sig) { }
static inline void sched_autogroup_exit(struct signal_struct *sig) { }
#endif

2363
extern int yield_to(struct task_struct *p, bool preempt);
2364 2365
extern void set_user_nice(struct task_struct *p, long nice);
extern int task_prio(const struct task_struct *p);
2366 2367 2368 2369 2370 2371 2372 2373 2374 2375
/**
 * task_nice - return the nice value of a given task.
 * @p: the task in question.
 *
 * Return: The nice value [ -20 ... 0 ... 19 ].
 */
static inline int task_nice(const struct task_struct *p)
{
	return PRIO_TO_NICE((p)->static_prio);
}
2376 2377
extern int can_nice(const struct task_struct *p, const int nice);
extern int task_curr(const struct task_struct *p);
L
Linus Torvalds 已提交
2378
extern int idle_cpu(int cpu);
2379 2380
extern int sched_setscheduler(struct task_struct *, int,
			      const struct sched_param *);
2381
extern int sched_setscheduler_nocheck(struct task_struct *, int,
2382
				      const struct sched_param *);
2383 2384
extern int sched_setattr(struct task_struct *,
			 const struct sched_attr *);
2385
extern struct task_struct *idle_task(int cpu);
2386 2387
/**
 * is_idle_task - is the specified task an idle task?
2388
 * @p: the task in question.
2389 2390
 *
 * Return: 1 if @p is an idle task. 0 otherwise.
2391
 */
2392
static inline bool is_idle_task(const struct task_struct *p)
2393 2394 2395
{
	return p->pid == 0;
}
2396 2397
extern struct task_struct *curr_task(int cpu);
extern void set_curr_task(int cpu, struct task_struct *p);
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2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420

void yield(void);

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;

2421 2422 2423 2424 2425 2426 2427
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
2428 2429
 * find_task_by_vpid():
 *      finds a task by its virtual pid
2430
 *
2431
 * see also find_vpid() etc in include/linux/pid.h
2432 2433
 */

2434 2435 2436
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);
2437

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2438
/* per-UID process charging. */
2439
extern struct user_struct * alloc_uid(kuid_t);
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2440 2441 2442 2443 2444 2445 2446 2447 2448
static inline struct user_struct *get_uid(struct user_struct *u)
{
	atomic_inc(&u->__count);
	return u;
}
extern void free_uid(struct user_struct *);

#include <asm/current.h>

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Torben Hohn 已提交
2449
extern void xtime_update(unsigned long ticks);
L
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2450

2451 2452
extern int wake_up_state(struct task_struct *tsk, unsigned int state);
extern int wake_up_process(struct task_struct *tsk);
2453
extern void wake_up_new_task(struct task_struct *tsk);
L
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2454 2455 2456 2457 2458
#ifdef CONFIG_SMP
 extern void kick_process(struct task_struct *tsk);
#else
 static inline void kick_process(struct task_struct *tsk) { }
#endif
2459
extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2460
extern void sched_dead(struct task_struct *p);
L
Linus Torvalds 已提交
2461 2462 2463

extern void proc_caches_init(void);
extern void flush_signals(struct task_struct *);
2464
extern void ignore_signals(struct task_struct *);
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2465 2466 2467
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);

2468
static inline int kernel_dequeue_signal(siginfo_t *info)
L
Linus Torvalds 已提交
2469
{
2470 2471
	struct task_struct *tsk = current;
	siginfo_t __info;
L
Linus Torvalds 已提交
2472 2473
	int ret;

2474 2475 2476
	spin_lock_irq(&tsk->sighand->siglock);
	ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info);
	spin_unlock_irq(&tsk->sighand->siglock);
L
Linus Torvalds 已提交
2477 2478

	return ret;
2479
}
L
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2480

2481 2482 2483 2484 2485 2486 2487 2488 2489 2490
static inline void kernel_signal_stop(void)
{
	spin_lock_irq(&current->sighand->siglock);
	if (current->jobctl & JOBCTL_STOP_DEQUEUED)
		__set_current_state(TASK_STOPPED);
	spin_unlock_irq(&current->sighand->siglock);

	schedule();
}

L
Linus Torvalds 已提交
2491 2492 2493 2494
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 *);
2495 2496
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);
2497 2498
extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
				const struct cred *, u32);
2499 2500
extern int kill_pgrp(struct pid *pid, int sig, int priv);
extern int kill_pid(struct pid *pid, int sig, int priv);
2501
extern int kill_proc_info(int, struct siginfo *, pid_t);
2502
extern __must_check bool do_notify_parent(struct task_struct *, int);
2503
extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
L
Linus Torvalds 已提交
2504 2505
extern void force_sig(int, struct task_struct *);
extern int send_sig(int, struct task_struct *, int);
2506
extern int zap_other_threads(struct task_struct *p);
L
Linus Torvalds 已提交
2507 2508
extern struct sigqueue *sigqueue_alloc(void);
extern void sigqueue_free(struct sigqueue *);
2509
extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2510
extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
L
Linus Torvalds 已提交
2511

A
Al Viro 已提交
2512 2513 2514
static inline void restore_saved_sigmask(void)
{
	if (test_and_clear_restore_sigmask())
2515
		__set_current_blocked(&current->saved_sigmask);
A
Al Viro 已提交
2516 2517
}

A
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2518 2519 2520 2521 2522 2523 2524 2525
static inline sigset_t *sigmask_to_save(void)
{
	sigset_t *res = &current->blocked;
	if (unlikely(test_restore_sigmask()))
		res = &current->saved_sigmask;
	return res;
}

2526 2527 2528 2529 2530
static inline int kill_cad_pid(int sig, int priv)
{
	return kill_pid(cad_pid, sig, priv);
}

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2531 2532 2533 2534 2535
/* 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)

2536 2537 2538
/*
 * True if we are on the alternate signal stack.
 */
L
Linus Torvalds 已提交
2539 2540
static inline int on_sig_stack(unsigned long sp)
{
2541 2542 2543 2544 2545 2546 2547
#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
L
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2548 2549 2550 2551
}

static inline int sas_ss_flags(unsigned long sp)
{
2552 2553 2554 2555
	if (!current->sas_ss_size)
		return SS_DISABLE;

	return on_sig_stack(sp) ? SS_ONSTACK : 0;
L
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2556 2557
}

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2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568
static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
{
	if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
#ifdef CONFIG_STACK_GROWSUP
		return current->sas_ss_sp;
#else
		return current->sas_ss_sp + current->sas_ss_size;
#endif
	return sp;
}

L
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2569 2570 2571 2572 2573 2574
/*
 * Routines for handling mm_structs
 */
extern struct mm_struct * mm_alloc(void);

/* mmdrop drops the mm and the page tables */
2575
extern void __mmdrop(struct mm_struct *);
L
Linus Torvalds 已提交
2576 2577
static inline void mmdrop(struct mm_struct * mm)
{
I
Ingo Molnar 已提交
2578
	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
L
Linus Torvalds 已提交
2579 2580 2581 2582 2583 2584 2585
		__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);
2586 2587 2588 2589 2590 2591
/*
 * Grab a reference to a task's mm, if it is not already going away
 * and ptrace_may_access with the mode parameter passed to it
 * succeeds.
 */
extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
L
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2592 2593 2594
/* Remove the current tasks stale references to the old mm_struct */
extern void mm_release(struct task_struct *, struct mm_struct *);

2595 2596 2597 2598
#ifdef CONFIG_HAVE_COPY_THREAD_TLS
extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
			struct task_struct *, unsigned long);
#else
A
Alexey Dobriyan 已提交
2599
extern int copy_thread(unsigned long, unsigned long, unsigned long,
2600
			struct task_struct *);
2601 2602 2603 2604 2605 2606 2607 2608 2609 2610

/* Architectures that haven't opted into copy_thread_tls get the tls argument
 * via pt_regs, so ignore the tls argument passed via C. */
static inline int copy_thread_tls(
		unsigned long clone_flags, unsigned long sp, unsigned long arg,
		struct task_struct *p, unsigned long tls)
{
	return copy_thread(clone_flags, sp, arg, p);
}
#endif
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2611 2612 2613 2614
extern void flush_thread(void);
extern void exit_thread(void);

extern void exit_files(struct task_struct *);
2615
extern void __cleanup_sighand(struct sighand_struct *);
2616

L
Linus Torvalds 已提交
2617
extern void exit_itimers(struct signal_struct *);
2618
extern void flush_itimer_signals(void);
L
Linus Torvalds 已提交
2619

2620
extern void do_group_exit(int);
L
Linus Torvalds 已提交
2621

2622
extern int do_execve(struct filename *,
2623
		     const char __user * const __user *,
2624
		     const char __user * const __user *);
2625 2626 2627 2628
extern int do_execveat(int, struct filename *,
		       const char __user * const __user *,
		       const char __user * const __user *,
		       int);
2629
extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2630
extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2631
struct task_struct *fork_idle(int);
2632
extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
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2633

2634 2635 2636 2637 2638
extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
static inline void set_task_comm(struct task_struct *tsk, const char *from)
{
	__set_task_comm(tsk, from, false);
}
2639
extern char *get_task_comm(char *to, struct task_struct *tsk);
L
Linus Torvalds 已提交
2640 2641

#ifdef CONFIG_SMP
2642
void scheduler_ipi(void);
R
Roland McGrath 已提交
2643
extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
L
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2644
#else
2645
static inline void scheduler_ipi(void) { }
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Roland McGrath 已提交
2646 2647 2648 2649 2650
static inline unsigned long wait_task_inactive(struct task_struct *p,
					       long match_state)
{
	return 1;
}
L
Linus Torvalds 已提交
2651 2652
#endif

2653 2654 2655
#define tasklist_empty() \
	list_empty(&init_task.tasks)

2656 2657
#define next_task(p) \
	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
L
Linus Torvalds 已提交
2658 2659 2660 2661

#define for_each_process(p) \
	for (p = &init_task ; (p = next_task(p)) != &init_task ; )

2662
extern bool current_is_single_threaded(void);
D
David Howells 已提交
2663

L
Linus Torvalds 已提交
2664 2665 2666 2667 2668 2669 2670 2671 2672 2673
/*
 * 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)

2674 2675 2676 2677 2678 2679 2680 2681 2682 2683
#define __for_each_thread(signal, t)	\
	list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)

#define for_each_thread(p, t)		\
	__for_each_thread((p)->signal, t)

/* Careful: this is a double loop, 'break' won't work as expected. */
#define for_each_process_thread(p, t)	\
	for_each_process(p) for_each_thread(p, t)

2684 2685
static inline int get_nr_threads(struct task_struct *tsk)
{
2686
	return tsk->signal->nr_threads;
2687 2688
}

2689 2690 2691 2692
static inline bool thread_group_leader(struct task_struct *p)
{
	return p->exit_signal >= 0;
}
L
Linus Torvalds 已提交
2693

2694 2695 2696 2697 2698 2699
/* 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.
 */
2700
static inline bool has_group_leader_pid(struct task_struct *p)
2701
{
2702
	return task_pid(p) == p->signal->leader_pid;
2703 2704
}

2705
static inline
2706
bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2707
{
2708
	return p1->signal == p2->signal;
2709 2710
}

2711
static inline struct task_struct *next_thread(const struct task_struct *p)
O
Oleg Nesterov 已提交
2712
{
2713 2714
	return list_entry_rcu(p->thread_group.next,
			      struct task_struct, thread_group);
O
Oleg Nesterov 已提交
2715 2716
}

A
Alexey Dobriyan 已提交
2717
static inline int thread_group_empty(struct task_struct *p)
L
Linus Torvalds 已提交
2718
{
O
Oleg Nesterov 已提交
2719
	return list_empty(&p->thread_group);
L
Linus Torvalds 已提交
2720 2721 2722 2723 2724 2725
}

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

/*
2726
 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2727
 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2728
 * pins the final release of task.io_context.  Also protects ->cpuset and
O
Oleg Nesterov 已提交
2729
 * ->cgroup.subsys[]. And ->vfork_done.
L
Linus Torvalds 已提交
2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744
 *
 * 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);
}

2745
extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2746 2747
							unsigned long *flags);

2748 2749 2750 2751 2752 2753 2754 2755 2756
static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
						       unsigned long *flags)
{
	struct sighand_struct *ret;

	ret = __lock_task_sighand(tsk, flags);
	(void)__cond_lock(&tsk->sighand->siglock, ret);
	return ret;
}
2757

2758 2759 2760 2761 2762 2763
static inline void unlock_task_sighand(struct task_struct *tsk,
						unsigned long *flags)
{
	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
}

2764
/**
2765 2766
 * threadgroup_change_begin - mark the beginning of changes to a threadgroup
 * @tsk: task causing the changes
2767
 *
2768 2769 2770 2771 2772 2773
 * All operations which modify a threadgroup - a new thread joining the
 * group, death of a member thread (the assertion of PF_EXITING) and
 * exec(2) dethreading the process and replacing the leader - are wrapped
 * by threadgroup_change_{begin|end}().  This is to provide a place which
 * subsystems needing threadgroup stability can hook into for
 * synchronization.
2774
 */
2775
static inline void threadgroup_change_begin(struct task_struct *tsk)
2776
{
2777 2778
	might_sleep();
	cgroup_threadgroup_change_begin(tsk);
2779
}
2780 2781

/**
2782 2783
 * threadgroup_change_end - mark the end of changes to a threadgroup
 * @tsk: task causing the changes
2784
 *
2785
 * See threadgroup_change_begin().
2786
 */
2787
static inline void threadgroup_change_end(struct task_struct *tsk)
2788
{
2789
	cgroup_threadgroup_change_end(tsk);
2790 2791
}

A
Al Viro 已提交
2792 2793
#ifndef __HAVE_THREAD_FUNCTIONS

R
Roman Zippel 已提交
2794 2795
#define task_thread_info(task)	((struct thread_info *)(task)->stack)
#define task_stack_page(task)	((task)->stack)
A
Al Viro 已提交
2796

2797 2798 2799 2800 2801 2802
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;
}

2803 2804 2805 2806 2807 2808 2809 2810 2811
/*
 * Return the address of the last usable long on the stack.
 *
 * When the stack grows down, this is just above the thread
 * info struct. Going any lower will corrupt the threadinfo.
 *
 * When the stack grows up, this is the highest address.
 * Beyond that position, we corrupt data on the next page.
 */
2812 2813
static inline unsigned long *end_of_stack(struct task_struct *p)
{
2814 2815 2816
#ifdef CONFIG_STACK_GROWSUP
	return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
#else
R
Roman Zippel 已提交
2817
	return (unsigned long *)(task_thread_info(p) + 1);
2818
#endif
2819 2820
}

A
Al Viro 已提交
2821
#endif
2822 2823
#define task_stack_end_corrupted(task) \
		(*(end_of_stack(task)) != STACK_END_MAGIC)
A
Al Viro 已提交
2824

2825 2826 2827 2828 2829 2830 2831
static inline int object_is_on_stack(void *obj)
{
	void *stack = task_stack_page(current);

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

2832 2833
extern void thread_info_cache_init(void);

2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845
#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
2846
extern void set_task_stack_end_magic(struct task_struct *tsk);
2847

L
Linus Torvalds 已提交
2848 2849 2850 2851 2852
/* 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)
{
A
Al Viro 已提交
2853
	set_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2854 2855 2856 2857
}

static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2858
	clear_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2859 2860 2861 2862
}

static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2863
	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2864 2865 2866 2867
}

static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2868
	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2869 2870 2871 2872
}

static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
{
A
Al Viro 已提交
2873
	return test_ti_thread_flag(task_thread_info(tsk), flag);
L
Linus Torvalds 已提交
2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885
}

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);
}

2886 2887 2888 2889 2890
static inline int test_tsk_need_resched(struct task_struct *tsk)
{
	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
}

2891 2892 2893 2894 2895 2896
static inline int restart_syscall(void)
{
	set_tsk_thread_flag(current, TIF_SIGPENDING);
	return -ERESTARTNOINTR;
}

L
Linus Torvalds 已提交
2897 2898 2899 2900
static inline int signal_pending(struct task_struct *p)
{
	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
}
M
Matthew Wilcox 已提交
2901

2902 2903 2904 2905
static inline int __fatal_signal_pending(struct task_struct *p)
{
	return unlikely(sigismember(&p->pending.signal, SIGKILL));
}
M
Matthew Wilcox 已提交
2906 2907 2908 2909 2910 2911

static inline int fatal_signal_pending(struct task_struct *p)
{
	return signal_pending(p) && __fatal_signal_pending(p);
}

2912 2913 2914 2915 2916 2917 2918 2919 2920 2921
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);
}

L
Linus Torvalds 已提交
2922 2923 2924 2925 2926 2927 2928
/*
 * 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.
 */
2929
extern int _cond_resched(void);
2930

2931
#define cond_resched() ({			\
2932
	___might_sleep(__FILE__, __LINE__, 0);	\
2933 2934
	_cond_resched();			\
})
2935

2936 2937 2938
extern int __cond_resched_lock(spinlock_t *lock);

#define cond_resched_lock(lock) ({				\
2939
	___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2940 2941 2942 2943 2944
	__cond_resched_lock(lock);				\
})

extern int __cond_resched_softirq(void);

2945
#define cond_resched_softirq() ({					\
2946
	___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2947
	__cond_resched_softirq();					\
2948
})
L
Linus Torvalds 已提交
2949

2950 2951 2952 2953 2954 2955 2956 2957 2958
static inline void cond_resched_rcu(void)
{
#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
	rcu_read_unlock();
	cond_resched();
	rcu_read_lock();
#endif
}

L
Linus Torvalds 已提交
2959 2960
/*
 * Does a critical section need to be broken due to another
N
Nick Piggin 已提交
2961 2962
 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
 * but a general need for low latency)
L
Linus Torvalds 已提交
2963
 */
N
Nick Piggin 已提交
2964
static inline int spin_needbreak(spinlock_t *lock)
L
Linus Torvalds 已提交
2965
{
N
Nick Piggin 已提交
2966 2967 2968
#ifdef CONFIG_PREEMPT
	return spin_is_contended(lock);
#else
L
Linus Torvalds 已提交
2969
	return 0;
N
Nick Piggin 已提交
2970
#endif
L
Linus Torvalds 已提交
2971 2972
}

2973 2974
/*
 * Idle thread specific functions to determine the need_resched
2975
 * polling state.
2976
 */
2977
#ifdef TIF_POLLING_NRFLAG
2978 2979 2980 2981
static inline int tsk_is_polling(struct task_struct *p)
{
	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
}
2982 2983

static inline void __current_set_polling(void)
2984 2985 2986 2987
{
	set_thread_flag(TIF_POLLING_NRFLAG);
}

2988 2989 2990 2991 2992 2993
static inline bool __must_check current_set_polling_and_test(void)
{
	__current_set_polling();

	/*
	 * Polling state must be visible before we test NEED_RESCHED,
2994
	 * paired by resched_curr()
2995
	 */
2996
	smp_mb__after_atomic();
2997 2998 2999 3000 3001

	return unlikely(tif_need_resched());
}

static inline void __current_clr_polling(void)
3002 3003 3004
{
	clear_thread_flag(TIF_POLLING_NRFLAG);
}
3005 3006 3007 3008 3009 3010 3011

static inline bool __must_check current_clr_polling_and_test(void)
{
	__current_clr_polling();

	/*
	 * Polling state must be visible before we test NEED_RESCHED,
3012
	 * paired by resched_curr()
3013
	 */
3014
	smp_mb__after_atomic();
3015 3016 3017 3018

	return unlikely(tif_need_resched());
}

3019 3020
#else
static inline int tsk_is_polling(struct task_struct *p) { return 0; }
3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031
static inline void __current_set_polling(void) { }
static inline void __current_clr_polling(void) { }

static inline bool __must_check current_set_polling_and_test(void)
{
	return unlikely(tif_need_resched());
}
static inline bool __must_check current_clr_polling_and_test(void)
{
	return unlikely(tif_need_resched());
}
3032 3033
#endif

3034 3035 3036 3037 3038 3039 3040 3041 3042 3043
static inline void current_clr_polling(void)
{
	__current_clr_polling();

	/*
	 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
	 * Once the bit is cleared, we'll get IPIs with every new
	 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
	 * fold.
	 */
3044
	smp_mb(); /* paired with resched_curr() */
3045 3046 3047 3048

	preempt_fold_need_resched();
}

3049 3050 3051 3052 3053
static __always_inline bool need_resched(void)
{
	return unlikely(tif_need_resched());
}

3054 3055 3056
/*
 * Thread group CPU time accounting.
 */
3057
void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
3058
void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
3059

R
Roland McGrath 已提交
3060 3061 3062 3063 3064 3065 3066
/*
 * 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);
L
Linus Torvalds 已提交
3067 3068
extern void recalc_sigpending(void);

3069 3070 3071 3072 3073 3074 3075 3076 3077 3078
extern void signal_wake_up_state(struct task_struct *t, unsigned int state);

static inline void signal_wake_up(struct task_struct *t, bool resume)
{
	signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
}
static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
{
	signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
}
L
Linus Torvalds 已提交
3079 3080 3081 3082 3083 3084 3085 3086

/*
 * 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)
{
A
Al Viro 已提交
3087
	return task_thread_info(p)->cpu;
L
Linus Torvalds 已提交
3088 3089
}

I
Ingo Molnar 已提交
3090 3091 3092 3093 3094
static inline int task_node(const struct task_struct *p)
{
	return cpu_to_node(task_cpu(p));
}

I
Ingo Molnar 已提交
3095
extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
L
Linus Torvalds 已提交
3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109

#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 */

3110 3111
extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3112

D
Dhaval Giani 已提交
3113
#ifdef CONFIG_CGROUP_SCHED
3114
extern struct task_group root_task_group;
P
Peter Zijlstra 已提交
3115
#endif /* CONFIG_CGROUP_SCHED */
3116

3117 3118 3119
extern int task_can_switch_user(struct user_struct *up,
					struct task_struct *tsk);

3120 3121 3122
#ifdef CONFIG_TASK_XACCT
static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
{
3123
	tsk->ioac.rchar += amt;
3124 3125 3126 3127
}

static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
{
3128
	tsk->ioac.wchar += amt;
3129 3130 3131 3132
}

static inline void inc_syscr(struct task_struct *tsk)
{
3133
	tsk->ioac.syscr++;
3134 3135 3136 3137
}

static inline void inc_syscw(struct task_struct *tsk)
{
3138
	tsk->ioac.syscw++;
3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157
}
#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

D
Dave Hansen 已提交
3158 3159 3160 3161
#ifndef TASK_SIZE_OF
#define TASK_SIZE_OF(tsk)	TASK_SIZE
#endif

O
Oleg Nesterov 已提交
3162
#ifdef CONFIG_MEMCG
3163 3164 3165 3166 3167
extern void mm_update_next_owner(struct mm_struct *mm);
#else
static inline void mm_update_next_owner(struct mm_struct *mm)
{
}
O
Oleg Nesterov 已提交
3168
#endif /* CONFIG_MEMCG */
3169

3170 3171 3172
static inline unsigned long task_rlimit(const struct task_struct *tsk,
		unsigned int limit)
{
3173
	return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3174 3175 3176 3177 3178
}

static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
		unsigned int limit)
{
3179
	return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191
}

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);
}

L
Linus Torvalds 已提交
3192
#endif