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v3.15
 
   1#ifndef _LINUX_SCHED_H
   2#define _LINUX_SCHED_H
   3
   4#include <uapi/linux/sched.h>
   5
   6#include <linux/sched/prio.h>
   7
   8
   9struct sched_param {
  10	int sched_priority;
  11};
  12
  13#include <asm/param.h>	/* for HZ */
  14
  15#include <linux/capability.h>
  16#include <linux/threads.h>
  17#include <linux/kernel.h>
  18#include <linux/types.h>
  19#include <linux/timex.h>
  20#include <linux/jiffies.h>
  21#include <linux/plist.h>
  22#include <linux/rbtree.h>
  23#include <linux/thread_info.h>
 
  24#include <linux/cpumask.h>
  25#include <linux/errno.h>
  26#include <linux/nodemask.h>
  27#include <linux/mm_types.h>
  28#include <linux/preempt_mask.h>
  29
  30#include <asm/page.h>
  31#include <asm/ptrace.h>
  32#include <linux/cputime.h>
  33
  34#include <linux/smp.h>
  35#include <linux/sem.h>
  36#include <linux/signal.h>
  37#include <linux/compiler.h>
  38#include <linux/completion.h>
  39#include <linux/pid.h>
  40#include <linux/percpu.h>
  41#include <linux/topology.h>
  42#include <linux/proportions.h>
  43#include <linux/seccomp.h>
  44#include <linux/rcupdate.h>
  45#include <linux/rculist.h>
  46#include <linux/rtmutex.h>
  47
  48#include <linux/time.h>
  49#include <linux/param.h>
 
 
 
 
 
 
 
 
 
 
 
 
  50#include <linux/resource.h>
  51#include <linux/timer.h>
  52#include <linux/hrtimer.h>
  53#include <linux/task_io_accounting.h>
  54#include <linux/latencytop.h>
  55#include <linux/cred.h>
  56#include <linux/llist.h>
  57#include <linux/uidgid.h>
  58#include <linux/gfp.h>
  59
  60#include <asm/processor.h>
  61
  62#define SCHED_ATTR_SIZE_VER0	48	/* sizeof first published struct */
  63
  64/*
  65 * Extended scheduling parameters data structure.
  66 *
  67 * This is needed because the original struct sched_param can not be
  68 * altered without introducing ABI issues with legacy applications
  69 * (e.g., in sched_getparam()).
  70 *
  71 * However, the possibility of specifying more than just a priority for
  72 * the tasks may be useful for a wide variety of application fields, e.g.,
  73 * multimedia, streaming, automation and control, and many others.
  74 *
  75 * This variant (sched_attr) is meant at describing a so-called
  76 * sporadic time-constrained task. In such model a task is specified by:
  77 *  - the activation period or minimum instance inter-arrival time;
  78 *  - the maximum (or average, depending on the actual scheduling
  79 *    discipline) computation time of all instances, a.k.a. runtime;
  80 *  - the deadline (relative to the actual activation time) of each
  81 *    instance.
  82 * Very briefly, a periodic (sporadic) task asks for the execution of
  83 * some specific computation --which is typically called an instance--
  84 * (at most) every period. Moreover, each instance typically lasts no more
  85 * than the runtime and must be completed by time instant t equal to
  86 * the instance activation time + the deadline.
  87 *
  88 * This is reflected by the actual fields of the sched_attr structure:
  89 *
  90 *  @size		size of the structure, for fwd/bwd compat.
  91 *
  92 *  @sched_policy	task's scheduling policy
  93 *  @sched_flags	for customizing the scheduler behaviour
  94 *  @sched_nice		task's nice value      (SCHED_NORMAL/BATCH)
  95 *  @sched_priority	task's static priority (SCHED_FIFO/RR)
  96 *  @sched_deadline	representative of the task's deadline
  97 *  @sched_runtime	representative of the task's runtime
  98 *  @sched_period	representative of the task's period
  99 *
 100 * Given this task model, there are a multiplicity of scheduling algorithms
 101 * and policies, that can be used to ensure all the tasks will make their
 102 * timing constraints.
 103 *
 104 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
 105 * only user of this new interface. More information about the algorithm
 106 * available in the scheduling class file or in Documentation/.
 107 */
 108struct sched_attr {
 109	u32 size;
 110
 111	u32 sched_policy;
 112	u64 sched_flags;
 113
 114	/* SCHED_NORMAL, SCHED_BATCH */
 115	s32 sched_nice;
 116
 117	/* SCHED_FIFO, SCHED_RR */
 118	u32 sched_priority;
 119
 120	/* SCHED_DEADLINE */
 121	u64 sched_runtime;
 122	u64 sched_deadline;
 123	u64 sched_period;
 124};
 125
 126struct exec_domain;
 127struct futex_pi_state;
 128struct robust_list_head;
 129struct bio_list;
 
 
 
 
 
 130struct fs_struct;
 
 
 
 
 
 
 131struct perf_event_context;
 132struct blk_plug;
 133struct filename;
 134
 135#define VMACACHE_BITS 2
 136#define VMACACHE_SIZE (1U << VMACACHE_BITS)
 137#define VMACACHE_MASK (VMACACHE_SIZE - 1)
 138
 139/*
 140 * List of flags we want to share for kernel threads,
 141 * if only because they are not used by them anyway.
 142 */
 143#define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
 144
 145/*
 146 * These are the constant used to fake the fixed-point load-average
 147 * counting. Some notes:
 148 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 149 *    a load-average precision of 10 bits integer + 11 bits fractional
 150 *  - if you want to count load-averages more often, you need more
 151 *    precision, or rounding will get you. With 2-second counting freq,
 152 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 153 *    11 bit fractions.
 154 */
 155extern unsigned long avenrun[];		/* Load averages */
 156extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
 157
 158#define FSHIFT		11		/* nr of bits of precision */
 159#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
 160#define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
 161#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
 162#define EXP_5		2014		/* 1/exp(5sec/5min) */
 163#define EXP_15		2037		/* 1/exp(5sec/15min) */
 164
 165#define CALC_LOAD(load,exp,n) \
 166	load *= exp; \
 167	load += n*(FIXED_1-exp); \
 168	load >>= FSHIFT;
 169
 170extern unsigned long total_forks;
 171extern int nr_threads;
 172DECLARE_PER_CPU(unsigned long, process_counts);
 173extern int nr_processes(void);
 174extern unsigned long nr_running(void);
 175extern unsigned long nr_iowait(void);
 176extern unsigned long nr_iowait_cpu(int cpu);
 177extern unsigned long this_cpu_load(void);
 178
 179
 180extern void calc_global_load(unsigned long ticks);
 181extern void update_cpu_load_nohz(void);
 182
 183extern unsigned long get_parent_ip(unsigned long addr);
 184
 185extern void dump_cpu_task(int cpu);
 186
 187struct seq_file;
 188struct cfs_rq;
 
 
 189struct task_group;
 190#ifdef CONFIG_SCHED_DEBUG
 191extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
 192extern void proc_sched_set_task(struct task_struct *p);
 193extern void
 194print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
 195#endif
 196
 197/*
 198 * Task state bitmask. NOTE! These bits are also
 199 * encoded in fs/proc/array.c: get_task_state().
 200 *
 201 * We have two separate sets of flags: task->state
 202 * is about runnability, while task->exit_state are
 203 * about the task exiting. Confusing, but this way
 204 * modifying one set can't modify the other one by
 205 * mistake.
 206 */
 207#define TASK_RUNNING		0
 208#define TASK_INTERRUPTIBLE	1
 209#define TASK_UNINTERRUPTIBLE	2
 210#define __TASK_STOPPED		4
 211#define __TASK_TRACED		8
 212/* in tsk->exit_state */
 213#define EXIT_DEAD		16
 214#define EXIT_ZOMBIE		32
 215#define EXIT_TRACE		(EXIT_ZOMBIE | EXIT_DEAD)
 216/* in tsk->state again */
 217#define TASK_DEAD		64
 218#define TASK_WAKEKILL		128
 219#define TASK_WAKING		256
 220#define TASK_PARKED		512
 221#define TASK_STATE_MAX		1024
 222
 223#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWP"
 224
 225extern char ___assert_task_state[1 - 2*!!(
 226		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
 227
 228/* Convenience macros for the sake of set_task_state */
 229#define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
 230#define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
 231#define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
 232
 233/* Convenience macros for the sake of wake_up */
 234#define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
 235#define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
 236
 237/* get_task_state() */
 238#define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
 239				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
 240				 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
 241
 242#define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
 243#define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
 244#define task_is_stopped_or_traced(task)	\
 245			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
 246#define task_contributes_to_load(task)	\
 247				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
 248				 (task->flags & PF_FROZEN) == 0)
 249
 250#define __set_task_state(tsk, state_value)		\
 251	do { (tsk)->state = (state_value); } while (0)
 252#define set_task_state(tsk, state_value)		\
 253	set_mb((tsk)->state, (state_value))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 254
 255/*
 256 * set_current_state() includes a barrier so that the write of current->state
 257 * is correctly serialised wrt the caller's subsequent test of whether to
 258 * actually sleep:
 259 *
 
 260 *	set_current_state(TASK_UNINTERRUPTIBLE);
 261 *	if (do_i_need_to_sleep())
 262 *		schedule();
 263 *
 264 * If the caller does not need such serialisation then use __set_current_state()
 265 */
 266#define __set_current_state(state_value)			\
 267	do { current->state = (state_value); } while (0)
 268#define set_current_state(state_value)		\
 269	set_mb(current->state, (state_value))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 270
 271/* Task command name length */
 272#define TASK_COMM_LEN 16
 273
 274#include <linux/spinlock.h>
 275
 276/*
 277 * This serializes "schedule()" and also protects
 278 * the run-queue from deletions/modifications (but
 279 * _adding_ to the beginning of the run-queue has
 280 * a separate lock).
 281 */
 282extern rwlock_t tasklist_lock;
 283extern spinlock_t mmlist_lock;
 284
 285struct task_struct;
 286
 287#ifdef CONFIG_PROVE_RCU
 288extern int lockdep_tasklist_lock_is_held(void);
 289#endif /* #ifdef CONFIG_PROVE_RCU */
 290
 291extern void sched_init(void);
 292extern void sched_init_smp(void);
 293extern asmlinkage void schedule_tail(struct task_struct *prev);
 294extern void init_idle(struct task_struct *idle, int cpu);
 295extern void init_idle_bootup_task(struct task_struct *idle);
 296
 297extern int runqueue_is_locked(int cpu);
 298
 299#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
 300extern void nohz_balance_enter_idle(int cpu);
 301extern void set_cpu_sd_state_idle(void);
 302extern int get_nohz_timer_target(int pinned);
 303#else
 304static inline void nohz_balance_enter_idle(int cpu) { }
 305static inline void set_cpu_sd_state_idle(void) { }
 306static inline int get_nohz_timer_target(int pinned)
 307{
 308	return smp_processor_id();
 309}
 310#endif
 311
 312/*
 313 * Only dump TASK_* tasks. (0 for all tasks)
 314 */
 315extern void show_state_filter(unsigned long state_filter);
 316
 317static inline void show_state(void)
 318{
 319	show_state_filter(0);
 320}
 321
 322extern void show_regs(struct pt_regs *);
 323
 324/*
 325 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 326 * task), SP is the stack pointer of the first frame that should be shown in the back
 327 * trace (or NULL if the entire call-chain of the task should be shown).
 328 */
 329extern void show_stack(struct task_struct *task, unsigned long *sp);
 330
 331void io_schedule(void);
 332long io_schedule_timeout(long timeout);
 333
 334extern void cpu_init (void);
 335extern void trap_init(void);
 336extern void update_process_times(int user);
 337extern void scheduler_tick(void);
 338
 339extern void sched_show_task(struct task_struct *p);
 340
 341#ifdef CONFIG_LOCKUP_DETECTOR
 342extern void touch_softlockup_watchdog(void);
 343extern void touch_softlockup_watchdog_sync(void);
 344extern void touch_all_softlockup_watchdogs(void);
 345extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
 346				  void __user *buffer,
 347				  size_t *lenp, loff_t *ppos);
 348extern unsigned int  softlockup_panic;
 349void lockup_detector_init(void);
 350#else
 351static inline void touch_softlockup_watchdog(void)
 352{
 353}
 354static inline void touch_softlockup_watchdog_sync(void)
 355{
 356}
 357static inline void touch_all_softlockup_watchdogs(void)
 358{
 359}
 360static inline void lockup_detector_init(void)
 361{
 362}
 363#endif
 364
 365#ifdef CONFIG_DETECT_HUNG_TASK
 366void reset_hung_task_detector(void);
 367#else
 368static inline void reset_hung_task_detector(void)
 369{
 370}
 371#endif
 372
 373/* Attach to any functions which should be ignored in wchan output. */
 374#define __sched		__attribute__((__section__(".sched.text")))
 375
 376/* Linker adds these: start and end of __sched functions */
 377extern char __sched_text_start[], __sched_text_end[];
 378
 379/* Is this address in the __sched functions? */
 380extern int in_sched_functions(unsigned long addr);
 381
 382#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
 383extern signed long schedule_timeout(signed long timeout);
 384extern signed long schedule_timeout_interruptible(signed long timeout);
 385extern signed long schedule_timeout_killable(signed long timeout);
 386extern signed long schedule_timeout_uninterruptible(signed long timeout);
 387asmlinkage void schedule(void);
 388extern void schedule_preempt_disabled(void);
 389
 390struct nsproxy;
 391struct user_namespace;
 392
 393#ifdef CONFIG_MMU
 394extern void arch_pick_mmap_layout(struct mm_struct *mm);
 395extern unsigned long
 396arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
 397		       unsigned long, unsigned long);
 398extern unsigned long
 399arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 400			  unsigned long len, unsigned long pgoff,
 401			  unsigned long flags);
 402#else
 403static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
 404#endif
 405
 406#define SUID_DUMP_DISABLE	0	/* No setuid dumping */
 407#define SUID_DUMP_USER		1	/* Dump as user of process */
 408#define SUID_DUMP_ROOT		2	/* Dump as root */
 409
 410/* mm flags */
 411
 412/* for SUID_DUMP_* above */
 413#define MMF_DUMPABLE_BITS 2
 414#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
 415
 416extern void set_dumpable(struct mm_struct *mm, int value);
 417/*
 418 * This returns the actual value of the suid_dumpable flag. For things
 419 * that are using this for checking for privilege transitions, it must
 420 * test against SUID_DUMP_USER rather than treating it as a boolean
 421 * value.
 422 */
 423static inline int __get_dumpable(unsigned long mm_flags)
 424{
 425	return mm_flags & MMF_DUMPABLE_MASK;
 426}
 427
 428static inline int get_dumpable(struct mm_struct *mm)
 429{
 430	return __get_dumpable(mm->flags);
 431}
 432
 433/* coredump filter bits */
 434#define MMF_DUMP_ANON_PRIVATE	2
 435#define MMF_DUMP_ANON_SHARED	3
 436#define MMF_DUMP_MAPPED_PRIVATE	4
 437#define MMF_DUMP_MAPPED_SHARED	5
 438#define MMF_DUMP_ELF_HEADERS	6
 439#define MMF_DUMP_HUGETLB_PRIVATE 7
 440#define MMF_DUMP_HUGETLB_SHARED  8
 441
 442#define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
 443#define MMF_DUMP_FILTER_BITS	7
 444#define MMF_DUMP_FILTER_MASK \
 445	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
 446#define MMF_DUMP_FILTER_DEFAULT \
 447	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
 448	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
 449
 450#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
 451# define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
 452#else
 453# define MMF_DUMP_MASK_DEFAULT_ELF	0
 454#endif
 455					/* leave room for more dump flags */
 456#define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
 457#define MMF_VM_HUGEPAGE		17	/* set when VM_HUGEPAGE is set on vma */
 458#define MMF_EXE_FILE_CHANGED	18	/* see prctl_set_mm_exe_file() */
 459
 460#define MMF_HAS_UPROBES		19	/* has uprobes */
 461#define MMF_RECALC_UPROBES	20	/* MMF_HAS_UPROBES can be wrong */
 462
 463#define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
 464
 465struct sighand_struct {
 466	atomic_t		count;
 467	struct k_sigaction	action[_NSIG];
 468	spinlock_t		siglock;
 469	wait_queue_head_t	signalfd_wqh;
 470};
 471
 472struct pacct_struct {
 473	int			ac_flag;
 474	long			ac_exitcode;
 475	unsigned long		ac_mem;
 476	cputime_t		ac_utime, ac_stime;
 477	unsigned long		ac_minflt, ac_majflt;
 478};
 479
 480struct cpu_itimer {
 481	cputime_t expires;
 482	cputime_t incr;
 483	u32 error;
 484	u32 incr_error;
 485};
 486
 487/**
 488 * struct cputime - snaphsot of system and user cputime
 489 * @utime: time spent in user mode
 490 * @stime: time spent in system mode
 
 491 *
 492 * Gathers a generic snapshot of user and system time.
 493 */
 494struct cputime {
 495	cputime_t utime;
 496	cputime_t stime;
 497};
 498
 499/**
 500 * struct task_cputime - collected CPU time counts
 501 * @utime:		time spent in user mode, in &cputime_t units
 502 * @stime:		time spent in kernel mode, in &cputime_t units
 503 * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
 504 *
 505 * This is an extension of struct cputime that includes the total runtime
 506 * spent by the task from the scheduler point of view.
 507 *
 508 * As a result, this structure groups together three kinds of CPU time
 509 * that are tracked for threads and thread groups.  Most things considering
 510 * CPU time want to group these counts together and treat all three
 511 * of them in parallel.
 512 */
 513struct task_cputime {
 514	cputime_t utime;
 515	cputime_t stime;
 516	unsigned long long sum_exec_runtime;
 517};
 518/* Alternate field names when used to cache expirations. */
 519#define prof_exp	stime
 520#define virt_exp	utime
 521#define sched_exp	sum_exec_runtime
 522
 523#define INIT_CPUTIME	\
 524	(struct task_cputime) {					\
 525		.utime = 0,					\
 526		.stime = 0,					\
 527		.sum_exec_runtime = 0,				\
 528	}
 529
 530#ifdef CONFIG_PREEMPT_COUNT
 531#define PREEMPT_DISABLED	(1 + PREEMPT_ENABLED)
 532#else
 533#define PREEMPT_DISABLED	PREEMPT_ENABLED
 534#endif
 535
 536/*
 537 * Disable preemption until the scheduler is running.
 538 * Reset by start_kernel()->sched_init()->init_idle().
 539 *
 540 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
 541 * before the scheduler is active -- see should_resched().
 542 */
 543#define INIT_PREEMPT_COUNT	(PREEMPT_DISABLED + PREEMPT_ACTIVE)
 544
 545/**
 546 * struct thread_group_cputimer - thread group interval timer counts
 547 * @cputime:		thread group interval timers.
 548 * @running:		non-zero when there are timers running and
 549 * 			@cputime receives updates.
 550 * @lock:		lock for fields in this struct.
 551 *
 552 * This structure contains the version of task_cputime, above, that is
 553 * used for thread group CPU timer calculations.
 554 */
 555struct thread_group_cputimer {
 556	struct task_cputime cputime;
 557	int running;
 558	raw_spinlock_t lock;
 559};
 560
 561#include <linux/rwsem.h>
 562struct autogroup;
 563
 564/*
 565 * NOTE! "signal_struct" does not have its own
 566 * locking, because a shared signal_struct always
 567 * implies a shared sighand_struct, so locking
 568 * sighand_struct is always a proper superset of
 569 * the locking of signal_struct.
 570 */
 571struct signal_struct {
 572	atomic_t		sigcnt;
 573	atomic_t		live;
 574	int			nr_threads;
 575	struct list_head	thread_head;
 576
 577	wait_queue_head_t	wait_chldexit;	/* for wait4() */
 578
 579	/* current thread group signal load-balancing target: */
 580	struct task_struct	*curr_target;
 581
 582	/* shared signal handling: */
 583	struct sigpending	shared_pending;
 584
 585	/* thread group exit support */
 586	int			group_exit_code;
 587	/* overloaded:
 588	 * - notify group_exit_task when ->count is equal to notify_count
 589	 * - everyone except group_exit_task is stopped during signal delivery
 590	 *   of fatal signals, group_exit_task processes the signal.
 591	 */
 592	int			notify_count;
 593	struct task_struct	*group_exit_task;
 594
 595	/* thread group stop support, overloads group_exit_code too */
 596	int			group_stop_count;
 597	unsigned int		flags; /* see SIGNAL_* flags below */
 598
 599	/*
 600	 * PR_SET_CHILD_SUBREAPER marks a process, like a service
 601	 * manager, to re-parent orphan (double-forking) child processes
 602	 * to this process instead of 'init'. The service manager is
 603	 * able to receive SIGCHLD signals and is able to investigate
 604	 * the process until it calls wait(). All children of this
 605	 * process will inherit a flag if they should look for a
 606	 * child_subreaper process at exit.
 607	 */
 608	unsigned int		is_child_subreaper:1;
 609	unsigned int		has_child_subreaper:1;
 610
 611	/* POSIX.1b Interval Timers */
 612	int			posix_timer_id;
 613	struct list_head	posix_timers;
 614
 615	/* ITIMER_REAL timer for the process */
 616	struct hrtimer real_timer;
 617	struct pid *leader_pid;
 618	ktime_t it_real_incr;
 619
 620	/*
 621	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
 622	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
 623	 * values are defined to 0 and 1 respectively
 624	 */
 625	struct cpu_itimer it[2];
 626
 627	/*
 628	 * Thread group totals for process CPU timers.
 629	 * See thread_group_cputimer(), et al, for details.
 630	 */
 631	struct thread_group_cputimer cputimer;
 632
 633	/* Earliest-expiration cache. */
 634	struct task_cputime cputime_expires;
 635
 636	struct list_head cpu_timers[3];
 637
 638	struct pid *tty_old_pgrp;
 639
 640	/* boolean value for session group leader */
 641	int leader;
 642
 643	struct tty_struct *tty; /* NULL if no tty */
 644
 645#ifdef CONFIG_SCHED_AUTOGROUP
 646	struct autogroup *autogroup;
 647#endif
 648	/*
 649	 * Cumulative resource counters for dead threads in the group,
 650	 * and for reaped dead child processes forked by this group.
 651	 * Live threads maintain their own counters and add to these
 652	 * in __exit_signal, except for the group leader.
 653	 */
 654	cputime_t utime, stime, cutime, cstime;
 655	cputime_t gtime;
 656	cputime_t cgtime;
 657#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 658	struct cputime prev_cputime;
 
 
 659#endif
 660	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 661	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 662	unsigned long inblock, oublock, cinblock, coublock;
 663	unsigned long maxrss, cmaxrss;
 664	struct task_io_accounting ioac;
 665
 666	/*
 667	 * Cumulative ns of schedule CPU time fo dead threads in the
 668	 * group, not including a zombie group leader, (This only differs
 669	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
 670	 * other than jiffies.)
 671	 */
 672	unsigned long long sum_sched_runtime;
 673
 674	/*
 675	 * We don't bother to synchronize most readers of this at all,
 676	 * because there is no reader checking a limit that actually needs
 677	 * to get both rlim_cur and rlim_max atomically, and either one
 678	 * alone is a single word that can safely be read normally.
 679	 * getrlimit/setrlimit use task_lock(current->group_leader) to
 680	 * protect this instead of the siglock, because they really
 681	 * have no need to disable irqs.
 682	 */
 683	struct rlimit rlim[RLIM_NLIMITS];
 684
 685#ifdef CONFIG_BSD_PROCESS_ACCT
 686	struct pacct_struct pacct;	/* per-process accounting information */
 687#endif
 688#ifdef CONFIG_TASKSTATS
 689	struct taskstats *stats;
 690#endif
 691#ifdef CONFIG_AUDIT
 692	unsigned audit_tty;
 693	unsigned audit_tty_log_passwd;
 694	struct tty_audit_buf *tty_audit_buf;
 695#endif
 696#ifdef CONFIG_CGROUPS
 697	/*
 698	 * group_rwsem prevents new tasks from entering the threadgroup and
 699	 * member tasks from exiting,a more specifically, setting of
 700	 * PF_EXITING.  fork and exit paths are protected with this rwsem
 701	 * using threadgroup_change_begin/end().  Users which require
 702	 * threadgroup to remain stable should use threadgroup_[un]lock()
 703	 * which also takes care of exec path.  Currently, cgroup is the
 704	 * only user.
 705	 */
 706	struct rw_semaphore group_rwsem;
 707#endif
 708
 709	oom_flags_t oom_flags;
 710	short oom_score_adj;		/* OOM kill score adjustment */
 711	short oom_score_adj_min;	/* OOM kill score adjustment min value.
 712					 * Only settable by CAP_SYS_RESOURCE. */
 713
 714	struct mutex cred_guard_mutex;	/* guard against foreign influences on
 715					 * credential calculations
 716					 * (notably. ptrace) */
 717};
 718
 719/*
 720 * Bits in flags field of signal_struct.
 721 */
 722#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
 723#define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */
 724#define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */
 725#define SIGNAL_GROUP_COREDUMP	0x00000008 /* coredump in progress */
 726/*
 727 * Pending notifications to parent.
 728 */
 729#define SIGNAL_CLD_STOPPED	0x00000010
 730#define SIGNAL_CLD_CONTINUED	0x00000020
 731#define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
 732
 733#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
 734
 735/* If true, all threads except ->group_exit_task have pending SIGKILL */
 736static inline int signal_group_exit(const struct signal_struct *sig)
 737{
 738	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
 739		(sig->group_exit_task != NULL);
 740}
 741
 742/*
 743 * Some day this will be a full-fledged user tracking system..
 744 */
 745struct user_struct {
 746	atomic_t __count;	/* reference count */
 747	atomic_t processes;	/* How many processes does this user have? */
 748	atomic_t files;		/* How many open files does this user have? */
 749	atomic_t sigpending;	/* How many pending signals does this user have? */
 750#ifdef CONFIG_INOTIFY_USER
 751	atomic_t inotify_watches; /* How many inotify watches does this user have? */
 752	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
 753#endif
 754#ifdef CONFIG_FANOTIFY
 755	atomic_t fanotify_listeners;
 756#endif
 757#ifdef CONFIG_EPOLL
 758	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
 759#endif
 760#ifdef CONFIG_POSIX_MQUEUE
 761	/* protected by mq_lock	*/
 762	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
 763#endif
 764	unsigned long locked_shm; /* How many pages of mlocked shm ? */
 765
 766#ifdef CONFIG_KEYS
 767	struct key *uid_keyring;	/* UID specific keyring */
 768	struct key *session_keyring;	/* UID's default session keyring */
 769#endif
 770
 771	/* Hash table maintenance information */
 772	struct hlist_node uidhash_node;
 773	kuid_t uid;
 774
 775#ifdef CONFIG_PERF_EVENTS
 776	atomic_long_t locked_vm;
 777#endif
 778};
 779
 780extern int uids_sysfs_init(void);
 781
 782extern struct user_struct *find_user(kuid_t);
 783
 784extern struct user_struct root_user;
 785#define INIT_USER (&root_user)
 786
 787
 788struct backing_dev_info;
 789struct reclaim_state;
 790
 791#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 792struct sched_info {
 793	/* cumulative counters */
 794	unsigned long pcount;	      /* # of times run on this cpu */
 795	unsigned long long run_delay; /* time spent waiting on a runqueue */
 796
 797	/* timestamps */
 798	unsigned long long last_arrival,/* when we last ran on a cpu */
 799			   last_queued;	/* when we were last queued to run */
 800};
 801#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
 802
 803#ifdef CONFIG_TASK_DELAY_ACCT
 804struct task_delay_info {
 805	spinlock_t	lock;
 806	unsigned int	flags;	/* Private per-task flags */
 807
 808	/* For each stat XXX, add following, aligned appropriately
 809	 *
 810	 * struct timespec XXX_start, XXX_end;
 811	 * u64 XXX_delay;
 812	 * u32 XXX_count;
 813	 *
 814	 * Atomicity of updates to XXX_delay, XXX_count protected by
 815	 * single lock above (split into XXX_lock if contention is an issue).
 816	 */
 817
 818	/*
 819	 * XXX_count is incremented on every XXX operation, the delay
 820	 * associated with the operation is added to XXX_delay.
 821	 * XXX_delay contains the accumulated delay time in nanoseconds.
 822	 */
 823	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
 824	u64 blkio_delay;	/* wait for sync block io completion */
 825	u64 swapin_delay;	/* wait for swapin block io completion */
 826	u32 blkio_count;	/* total count of the number of sync block */
 827				/* io operations performed */
 828	u32 swapin_count;	/* total count of the number of swapin block */
 829				/* io operations performed */
 830
 831	struct timespec freepages_start, freepages_end;
 832	u64 freepages_delay;	/* wait for memory reclaim */
 833	u32 freepages_count;	/* total count of memory reclaim */
 834};
 835#endif	/* CONFIG_TASK_DELAY_ACCT */
 836
 837static inline int sched_info_on(void)
 838{
 839#ifdef CONFIG_SCHEDSTATS
 840	return 1;
 841#elif defined(CONFIG_TASK_DELAY_ACCT)
 842	extern int delayacct_on;
 843	return delayacct_on;
 844#else
 845	return 0;
 846#endif
 847}
 848
 849enum cpu_idle_type {
 850	CPU_IDLE,
 851	CPU_NOT_IDLE,
 852	CPU_NEWLY_IDLE,
 853	CPU_MAX_IDLE_TYPES
 854};
 855
 856/*
 857 * Increase resolution of cpu_power calculations
 858 */
 859#define SCHED_POWER_SHIFT	10
 860#define SCHED_POWER_SCALE	(1L << SCHED_POWER_SHIFT)
 861
 862/*
 863 * sched-domains (multiprocessor balancing) declarations:
 
 
 
 
 864 */
 865#ifdef CONFIG_SMP
 866#define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
 867#define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
 868#define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
 869#define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
 870#define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
 871#define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
 872#define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
 873#define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
 874#define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
 875#define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
 876#define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
 877#define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
 878#define SD_NUMA			0x4000	/* cross-node balancing */
 879
 880extern int __weak arch_sd_sibiling_asym_packing(void);
 881
 882struct sched_domain_attr {
 883	int relax_domain_level;
 884};
 885
 886#define SD_ATTR_INIT	(struct sched_domain_attr) {	\
 887	.relax_domain_level = -1,			\
 888}
 889
 890extern int sched_domain_level_max;
 891
 892struct sched_group;
 893
 894struct sched_domain {
 895	/* These fields must be setup */
 896	struct sched_domain *parent;	/* top domain must be null terminated */
 897	struct sched_domain *child;	/* bottom domain must be null terminated */
 898	struct sched_group *groups;	/* the balancing groups of the domain */
 899	unsigned long min_interval;	/* Minimum balance interval ms */
 900	unsigned long max_interval;	/* Maximum balance interval ms */
 901	unsigned int busy_factor;	/* less balancing by factor if busy */
 902	unsigned int imbalance_pct;	/* No balance until over watermark */
 903	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
 904	unsigned int busy_idx;
 905	unsigned int idle_idx;
 906	unsigned int newidle_idx;
 907	unsigned int wake_idx;
 908	unsigned int forkexec_idx;
 909	unsigned int smt_gain;
 910
 911	int nohz_idle;			/* NOHZ IDLE status */
 912	int flags;			/* See SD_* */
 913	int level;
 914
 915	/* Runtime fields. */
 916	unsigned long last_balance;	/* init to jiffies. units in jiffies */
 917	unsigned int balance_interval;	/* initialise to 1. units in ms. */
 918	unsigned int nr_balance_failed; /* initialise to 0 */
 919
 920	/* idle_balance() stats */
 921	u64 max_newidle_lb_cost;
 922	unsigned long next_decay_max_lb_cost;
 923
 924#ifdef CONFIG_SCHEDSTATS
 925	/* load_balance() stats */
 926	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
 927	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
 928	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
 929	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
 930	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
 931	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
 932	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
 933	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
 934
 935	/* Active load balancing */
 936	unsigned int alb_count;
 937	unsigned int alb_failed;
 938	unsigned int alb_pushed;
 939
 940	/* SD_BALANCE_EXEC stats */
 941	unsigned int sbe_count;
 942	unsigned int sbe_balanced;
 943	unsigned int sbe_pushed;
 944
 945	/* SD_BALANCE_FORK stats */
 946	unsigned int sbf_count;
 947	unsigned int sbf_balanced;
 948	unsigned int sbf_pushed;
 949
 950	/* try_to_wake_up() stats */
 951	unsigned int ttwu_wake_remote;
 952	unsigned int ttwu_move_affine;
 953	unsigned int ttwu_move_balance;
 954#endif
 955#ifdef CONFIG_SCHED_DEBUG
 956	char *name;
 957#endif
 958	union {
 959		void *private;		/* used during construction */
 960		struct rcu_head rcu;	/* used during destruction */
 961	};
 962
 963	unsigned int span_weight;
 964	/*
 965	 * Span of all CPUs in this domain.
 966	 *
 967	 * NOTE: this field is variable length. (Allocated dynamically
 968	 * by attaching extra space to the end of the structure,
 969	 * depending on how many CPUs the kernel has booted up with)
 970	 */
 971	unsigned long span[0];
 972};
 973
 974static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
 975{
 976	return to_cpumask(sd->span);
 977}
 978
 979extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
 980				    struct sched_domain_attr *dattr_new);
 981
 982/* Allocate an array of sched domains, for partition_sched_domains(). */
 983cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
 984void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
 985
 986bool cpus_share_cache(int this_cpu, int that_cpu);
 987
 988#else /* CONFIG_SMP */
 989
 990struct sched_domain_attr;
 991
 992static inline void
 993partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
 994			struct sched_domain_attr *dattr_new)
 995{
 996}
 997
 998static inline bool cpus_share_cache(int this_cpu, int that_cpu)
 999{
1000	return true;
1001}
1002
1003#endif	/* !CONFIG_SMP */
1004
1005
1006struct io_context;			/* See blkdev.h */
1007
1008
1009#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1010extern void prefetch_stack(struct task_struct *t);
1011#else
1012static inline void prefetch_stack(struct task_struct *t) { }
1013#endif
1014
1015struct audit_context;		/* See audit.c */
1016struct mempolicy;
1017struct pipe_inode_info;
1018struct uts_namespace;
1019
1020struct load_weight {
1021	unsigned long weight;
1022	u32 inv_weight;
1023};
1024
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1025struct sched_avg {
1026	/*
1027	 * These sums represent an infinite geometric series and so are bound
1028	 * above by 1024/(1-y).  Thus we only need a u32 to store them for all
1029	 * choices of y < 1-2^(-32)*1024.
1030	 */
1031	u32 runnable_avg_sum, runnable_avg_period;
1032	u64 last_runnable_update;
1033	s64 decay_count;
1034	unsigned long load_avg_contrib;
1035};
 
 
 
 
 
 
 
 
 
 
 
1036
1037#ifdef CONFIG_SCHEDSTATS
1038struct sched_statistics {
1039	u64			wait_start;
1040	u64			wait_max;
1041	u64			wait_count;
1042	u64			wait_sum;
1043	u64			iowait_count;
1044	u64			iowait_sum;
1045
1046	u64			sleep_start;
1047	u64			sleep_max;
1048	s64			sum_sleep_runtime;
1049
1050	u64			block_start;
1051	u64			block_max;
1052	u64			exec_max;
1053	u64			slice_max;
1054
1055	u64			nr_migrations_cold;
1056	u64			nr_failed_migrations_affine;
1057	u64			nr_failed_migrations_running;
1058	u64			nr_failed_migrations_hot;
1059	u64			nr_forced_migrations;
1060
1061	u64			nr_wakeups;
1062	u64			nr_wakeups_sync;
1063	u64			nr_wakeups_migrate;
1064	u64			nr_wakeups_local;
1065	u64			nr_wakeups_remote;
1066	u64			nr_wakeups_affine;
1067	u64			nr_wakeups_affine_attempts;
1068	u64			nr_wakeups_passive;
1069	u64			nr_wakeups_idle;
1070};
 
 
 
 
 
1071#endif
 
 
1072
1073struct sched_entity {
1074	struct load_weight	load;		/* for load-balancing */
1075	struct rb_node		run_node;
1076	struct list_head	group_node;
1077	unsigned int		on_rq;
1078
1079	u64			exec_start;
1080	u64			sum_exec_runtime;
1081	u64			vruntime;
1082	u64			prev_sum_exec_runtime;
1083
1084	u64			nr_migrations;
 
 
 
 
1085
1086#ifdef CONFIG_SCHEDSTATS
1087	struct sched_statistics statistics;
1088#endif
1089
1090#ifdef CONFIG_FAIR_GROUP_SCHED
1091	int			depth;
1092	struct sched_entity	*parent;
1093	/* rq on which this entity is (to be) queued: */
1094	struct cfs_rq		*cfs_rq;
1095	/* rq "owned" by this entity/group: */
1096	struct cfs_rq		*my_q;
 
 
1097#endif
1098
1099#ifdef CONFIG_SMP
1100	/* Per-entity load-tracking */
1101	struct sched_avg	avg;
 
 
 
 
 
1102#endif
1103};
1104
1105struct sched_rt_entity {
1106	struct list_head run_list;
1107	unsigned long timeout;
1108	unsigned long watchdog_stamp;
1109	unsigned int time_slice;
 
 
1110
1111	struct sched_rt_entity *back;
1112#ifdef CONFIG_RT_GROUP_SCHED
1113	struct sched_rt_entity	*parent;
1114	/* rq on which this entity is (to be) queued: */
1115	struct rt_rq		*rt_rq;
1116	/* rq "owned" by this entity/group: */
1117	struct rt_rq		*my_q;
1118#endif
1119};
 
 
 
1120
1121struct sched_dl_entity {
1122	struct rb_node	rb_node;
1123
1124	/*
1125	 * Original scheduling parameters. Copied here from sched_attr
1126	 * during sched_setscheduler2(), they will remain the same until
1127	 * the next sched_setscheduler2().
1128	 */
1129	u64 dl_runtime;		/* maximum runtime for each instance	*/
1130	u64 dl_deadline;	/* relative deadline of each instance	*/
1131	u64 dl_period;		/* separation of two instances (period) */
1132	u64 dl_bw;		/* dl_runtime / dl_deadline		*/
 
1133
1134	/*
1135	 * Actual scheduling parameters. Initialized with the values above,
1136	 * they are continously updated during task execution. Note that
1137	 * the remaining runtime could be < 0 in case we are in overrun.
1138	 */
1139	s64 runtime;		/* remaining runtime for this instance	*/
1140	u64 deadline;		/* absolute deadline for this instance	*/
1141	unsigned int flags;	/* specifying the scheduler behaviour	*/
1142
1143	/*
1144	 * Some bool flags:
1145	 *
1146	 * @dl_throttled tells if we exhausted the runtime. If so, the
1147	 * task has to wait for a replenishment to be performed at the
1148	 * next firing of dl_timer.
1149	 *
1150	 * @dl_new tells if a new instance arrived. If so we must
1151	 * start executing it with full runtime and reset its absolute
1152	 * deadline;
1153	 *
1154	 * @dl_boosted tells if we are boosted due to DI. If so we are
1155	 * outside bandwidth enforcement mechanism (but only until we
1156	 * exit the critical section);
 
 
 
1157	 *
1158	 * @dl_yielded tells if task gave up the cpu before consuming
1159	 * all its available runtime during the last job.
1160	 */
1161	int dl_throttled, dl_new, dl_boosted, dl_yielded;
 
 
 
 
1162
1163	/*
1164	 * Bandwidth enforcement timer. Each -deadline task has its
1165	 * own bandwidth to be enforced, thus we need one timer per task.
1166	 */
1167	struct hrtimer dl_timer;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1168};
1169
1170struct rcu_node;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1171
1172enum perf_event_task_context {
1173	perf_invalid_context = -1,
1174	perf_hw_context = 0,
1175	perf_sw_context,
1176	perf_nr_task_contexts,
1177};
1178
 
 
 
 
 
 
 
 
 
 
 
1179struct task_struct {
1180	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1181	void *stack;
1182	atomic_t usage;
1183	unsigned int flags;	/* per process flags, defined below */
1184	unsigned int ptrace;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1185
1186#ifdef CONFIG_SMP
1187	struct llist_node wake_entry;
1188	int on_cpu;
1189	struct task_struct *last_wakee;
1190	unsigned long wakee_flips;
1191	unsigned long wakee_flip_decay_ts;
1192
1193	int wake_cpu;
1194#endif
1195	int on_rq;
1196
1197	int prio, static_prio, normal_prio;
1198	unsigned int rt_priority;
1199	const struct sched_class *sched_class;
1200	struct sched_entity se;
1201	struct sched_rt_entity rt;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1202#ifdef CONFIG_CGROUP_SCHED
1203	struct task_group *sched_task_group;
 
 
 
 
 
 
 
 
 
 
 
 
 
1204#endif
1205	struct sched_dl_entity dl;
 
1206
1207#ifdef CONFIG_PREEMPT_NOTIFIERS
1208	/* list of struct preempt_notifier: */
1209	struct hlist_head preempt_notifiers;
1210#endif
1211
1212#ifdef CONFIG_BLK_DEV_IO_TRACE
1213	unsigned int btrace_seq;
1214#endif
1215
1216	unsigned int policy;
1217	int nr_cpus_allowed;
1218	cpumask_t cpus_allowed;
 
 
 
 
 
 
 
1219
1220#ifdef CONFIG_PREEMPT_RCU
1221	int rcu_read_lock_nesting;
1222	char rcu_read_unlock_special;
1223	struct list_head rcu_node_entry;
 
1224#endif /* #ifdef CONFIG_PREEMPT_RCU */
1225#ifdef CONFIG_TREE_PREEMPT_RCU
1226	struct rcu_node *rcu_blocked_node;
1227#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1228#ifdef CONFIG_RCU_BOOST
1229	struct rt_mutex *rcu_boost_mutex;
1230#endif /* #ifdef CONFIG_RCU_BOOST */
1231
1232#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1233	struct sched_info sched_info;
1234#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1235
1236	struct list_head tasks;
1237#ifdef CONFIG_SMP
1238	struct plist_node pushable_tasks;
1239	struct rb_node pushable_dl_tasks;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1240#endif
1241
1242	struct mm_struct *mm, *active_mm;
 
 
 
 
 
 
 
 
 
 
 
 
1243#ifdef CONFIG_COMPAT_BRK
1244	unsigned brk_randomized:1;
1245#endif
1246	/* per-thread vma caching */
1247	u32 vmacache_seqnum;
1248	struct vm_area_struct *vmacache[VMACACHE_SIZE];
1249#if defined(SPLIT_RSS_COUNTING)
1250	struct task_rss_stat	rss_stat;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1251#endif
1252/* task state */
1253	int exit_state;
1254	int exit_code, exit_signal;
1255	int pdeath_signal;  /*  The signal sent when the parent dies  */
1256	unsigned int jobctl;	/* JOBCTL_*, siglock protected */
1257
1258	/* Used for emulating ABI behavior of previous Linux versions */
1259	unsigned int personality;
1260
1261	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1262				 * execve */
1263	unsigned in_iowait:1;
1264
1265	/* task may not gain privileges */
1266	unsigned no_new_privs:1;
1267
1268	/* Revert to default priority/policy when forking */
1269	unsigned sched_reset_on_fork:1;
1270	unsigned sched_contributes_to_load:1;
1271
1272	pid_t pid;
1273	pid_t tgid;
1274
1275#ifdef CONFIG_CC_STACKPROTECTOR
1276	/* Canary value for the -fstack-protector gcc feature */
1277	unsigned long stack_canary;
1278#endif
1279	/*
1280	 * pointers to (original) parent process, youngest child, younger sibling,
1281	 * older sibling, respectively.  (p->father can be replaced with
1282	 * p->real_parent->pid)
1283	 */
1284	struct task_struct __rcu *real_parent; /* real parent process */
1285	struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
 
 
 
 
 
1286	/*
1287	 * children/sibling forms the list of my natural children
1288	 */
1289	struct list_head children;	/* list of my children */
1290	struct list_head sibling;	/* linkage in my parent's children list */
1291	struct task_struct *group_leader;	/* threadgroup leader */
1292
1293	/*
1294	 * ptraced is the list of tasks this task is using ptrace on.
 
1295	 * This includes both natural children and PTRACE_ATTACH targets.
1296	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1297	 */
1298	struct list_head ptraced;
1299	struct list_head ptrace_entry;
1300
1301	/* PID/PID hash table linkage. */
1302	struct pid_link pids[PIDTYPE_MAX];
1303	struct list_head thread_group;
1304	struct list_head thread_node;
1305
1306	struct completion *vfork_done;		/* for vfork() */
1307	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1308	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1309
1310	cputime_t utime, stime, utimescaled, stimescaled;
1311	cputime_t gtime;
1312#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
1313	struct cputime prev_cputime;
 
 
 
 
 
 
 
 
 
 
 
 
1314#endif
 
 
1315#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1316	seqlock_t vtime_seqlock;
1317	unsigned long long vtime_snap;
1318	enum {
1319		VTIME_SLEEPING = 0,
1320		VTIME_USER,
1321		VTIME_SYS,
1322	} vtime_snap_whence;
1323#endif
1324	unsigned long nvcsw, nivcsw; /* context switch counts */
1325	struct timespec start_time; 		/* monotonic time */
1326	struct timespec real_start_time;	/* boot based time */
1327/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1328	unsigned long min_flt, maj_flt;
1329
1330	struct task_cputime cputime_expires;
1331	struct list_head cpu_timers[3];
1332
1333/* process credentials */
1334	const struct cred __rcu *real_cred; /* objective and real subjective task
1335					 * credentials (COW) */
1336	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1337					 * credentials (COW) */
1338	char comm[TASK_COMM_LEN]; /* executable name excluding path
1339				     - access with [gs]et_task_comm (which lock
1340				       it with task_lock())
1341				     - initialized normally by setup_new_exec */
1342/* file system info */
1343	int link_count, total_link_count;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1344#ifdef CONFIG_SYSVIPC
1345/* ipc stuff */
1346	struct sysv_sem sysvsem;
1347#endif
1348#ifdef CONFIG_DETECT_HUNG_TASK
1349/* hung task detection */
1350	unsigned long last_switch_count;
1351#endif
1352/* CPU-specific state of this task */
1353	struct thread_struct thread;
1354/* filesystem information */
1355	struct fs_struct *fs;
1356/* open file information */
1357	struct files_struct *files;
1358/* namespaces */
1359	struct nsproxy *nsproxy;
1360/* signal handlers */
1361	struct signal_struct *signal;
1362	struct sighand_struct *sighand;
1363
1364	sigset_t blocked, real_blocked;
1365	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1366	struct sigpending pending;
1367
1368	unsigned long sas_ss_sp;
1369	size_t sas_ss_size;
1370	int (*notifier)(void *priv);
1371	void *notifier_data;
1372	sigset_t *notifier_mask;
1373	struct callback_head *task_works;
 
 
1374
1375	struct audit_context *audit_context;
 
 
1376#ifdef CONFIG_AUDITSYSCALL
1377	kuid_t loginuid;
1378	unsigned int sessionid;
1379#endif
1380	struct seccomp seccomp;
 
 
 
 
 
 
 
 
1381
1382/* Thread group tracking */
1383   	u32 parent_exec_id;
1384   	u32 self_exec_id;
1385/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1386 * mempolicy */
1387	spinlock_t alloc_lock;
1388
1389	/* Protection of the PI data structures: */
1390	raw_spinlock_t pi_lock;
 
 
1391
1392#ifdef CONFIG_RT_MUTEXES
1393	/* PI waiters blocked on a rt_mutex held by this task */
1394	struct rb_root pi_waiters;
1395	struct rb_node *pi_waiters_leftmost;
1396	/* Deadlock detection and priority inheritance handling */
1397	struct rt_mutex_waiter *pi_blocked_on;
1398	/* Top pi_waiters task */
1399	struct task_struct *pi_top_task;
1400#endif
1401
1402#ifdef CONFIG_DEBUG_MUTEXES
1403	/* mutex deadlock detection */
1404	struct mutex_waiter *blocked_on;
 
 
 
 
1405#endif
 
1406#ifdef CONFIG_TRACE_IRQFLAGS
1407	unsigned int irq_events;
1408	unsigned long hardirq_enable_ip;
1409	unsigned long hardirq_disable_ip;
1410	unsigned int hardirq_enable_event;
1411	unsigned int hardirq_disable_event;
1412	int hardirqs_enabled;
1413	int hardirq_context;
1414	unsigned long softirq_disable_ip;
1415	unsigned long softirq_enable_ip;
1416	unsigned int softirq_disable_event;
1417	unsigned int softirq_enable_event;
1418	int softirqs_enabled;
1419	int softirq_context;
1420#endif
 
 
 
 
1421#ifdef CONFIG_LOCKDEP
1422# define MAX_LOCK_DEPTH 48UL
1423	u64 curr_chain_key;
1424	int lockdep_depth;
1425	unsigned int lockdep_recursion;
1426	struct held_lock held_locks[MAX_LOCK_DEPTH];
1427	gfp_t lockdep_reclaim_gfp;
 
 
 
1428#endif
1429
1430/* journalling filesystem info */
1431	void *journal_info;
1432
1433/* stacked block device info */
1434	struct bio_list *bio_list;
1435
1436#ifdef CONFIG_BLOCK
1437/* stack plugging */
1438	struct blk_plug *plug;
1439#endif
1440
1441/* VM state */
1442	struct reclaim_state *reclaim_state;
1443
1444	struct backing_dev_info *backing_dev_info;
1445
1446	struct io_context *io_context;
 
 
 
 
 
1447
1448	unsigned long ptrace_message;
1449	siginfo_t *last_siginfo; /* For ptrace use.  */
1450	struct task_io_accounting ioac;
1451#if defined(CONFIG_TASK_XACCT)
1452	u64 acct_rss_mem1;	/* accumulated rss usage */
1453	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1454	cputime_t acct_timexpd;	/* stime + utime since last update */
 
 
 
 
 
1455#endif
1456#ifdef CONFIG_CPUSETS
1457	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1458	seqcount_t mems_allowed_seq;	/* Seqence no to catch updates */
1459	int cpuset_mem_spread_rotor;
1460	int cpuset_slab_spread_rotor;
 
 
1461#endif
1462#ifdef CONFIG_CGROUPS
1463	/* Control Group info protected by css_set_lock */
1464	struct css_set __rcu *cgroups;
1465	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1466	struct list_head cg_list;
 
 
 
 
1467#endif
1468#ifdef CONFIG_FUTEX
1469	struct robust_list_head __user *robust_list;
1470#ifdef CONFIG_COMPAT
1471	struct compat_robust_list_head __user *compat_robust_list;
1472#endif
1473	struct list_head pi_state_list;
1474	struct futex_pi_state *pi_state_cache;
 
 
1475#endif
1476#ifdef CONFIG_PERF_EVENTS
1477	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1478	struct mutex perf_event_mutex;
1479	struct list_head perf_event_list;
1480#endif
1481#ifdef CONFIG_DEBUG_PREEMPT
1482	unsigned long preempt_disable_ip;
1483#endif
1484#ifdef CONFIG_NUMA
1485	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1486	short il_next;
1487	short pref_node_fork;
 
1488#endif
1489#ifdef CONFIG_NUMA_BALANCING
1490	int numa_scan_seq;
1491	unsigned int numa_scan_period;
1492	unsigned int numa_scan_period_max;
1493	int numa_preferred_nid;
1494	unsigned long numa_migrate_retry;
1495	u64 node_stamp;			/* migration stamp  */
1496	u64 last_task_numa_placement;
1497	u64 last_sum_exec_runtime;
1498	struct callback_head numa_work;
1499
1500	struct list_head numa_entry;
1501	struct numa_group *numa_group;
1502
1503	/*
1504	 * Exponential decaying average of faults on a per-node basis.
1505	 * Scheduling placement decisions are made based on the these counts.
1506	 * The values remain static for the duration of a PTE scan
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1507	 */
1508	unsigned long *numa_faults_memory;
1509	unsigned long total_numa_faults;
1510
1511	/*
1512	 * numa_faults_buffer records faults per node during the current
1513	 * scan window. When the scan completes, the counts in
1514	 * numa_faults_memory decay and these values are copied.
 
1515	 */
1516	unsigned long *numa_faults_buffer_memory;
1517
1518	/*
1519	 * Track the nodes the process was running on when a NUMA hinting
1520	 * fault was incurred.
1521	 */
1522	unsigned long *numa_faults_cpu;
1523	unsigned long *numa_faults_buffer_cpu;
1524
 
 
 
 
1525	/*
1526	 * numa_faults_locality tracks if faults recorded during the last
1527	 * scan window were remote/local. The task scan period is adapted
1528	 * based on the locality of the faults with different weights
1529	 * depending on whether they were shared or private faults
1530	 */
1531	unsigned long numa_faults_locality[2];
 
1532
1533	unsigned long numa_pages_migrated;
1534#endif /* CONFIG_NUMA_BALANCING */
 
 
 
 
 
1535
1536	struct rcu_head rcu;
1537
1538	/*
1539	 * cache last used pipe for splice
1540	 */
1541	struct pipe_inode_info *splice_pipe;
1542
1543	struct page_frag task_frag;
1544
1545#ifdef	CONFIG_TASK_DELAY_ACCT
1546	struct task_delay_info *delays;
1547#endif
 
1548#ifdef CONFIG_FAULT_INJECTION
1549	int make_it_fail;
 
1550#endif
1551	/*
1552	 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1553	 * balance_dirty_pages() for some dirty throttling pause
1554	 */
1555	int nr_dirtied;
1556	int nr_dirtied_pause;
1557	unsigned long dirty_paused_when; /* start of a write-and-pause period */
 
1558
1559#ifdef CONFIG_LATENCYTOP
1560	int latency_record_count;
1561	struct latency_record latency_record[LT_SAVECOUNT];
1562#endif
1563	/*
1564	 * time slack values; these are used to round up poll() and
1565	 * select() etc timeout values. These are in nanoseconds.
1566	 */
1567	unsigned long timer_slack_ns;
1568	unsigned long default_timer_slack_ns;
1569
1570#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1571	/* Index of current stored address in ret_stack */
1572	int curr_ret_stack;
1573	/* Stack of return addresses for return function tracing */
1574	struct ftrace_ret_stack	*ret_stack;
1575	/* time stamp for last schedule */
1576	unsigned long long ftrace_timestamp;
1577	/*
1578	 * Number of functions that haven't been traced
1579	 * because of depth overrun.
1580	 */
1581	atomic_t trace_overrun;
1582	/* Pause for the tracing */
1583	atomic_t tracing_graph_pause;
1584#endif
1585#ifdef CONFIG_TRACING
1586	/* state flags for use by tracers */
1587	unsigned long trace;
1588	/* bitmask and counter of trace recursion */
1589	unsigned long trace_recursion;
1590#endif /* CONFIG_TRACING */
1591#ifdef CONFIG_MEMCG /* memcg uses this to do batch job */
1592	struct memcg_batch_info {
1593		int do_batch;	/* incremented when batch uncharge started */
1594		struct mem_cgroup *memcg; /* target memcg of uncharge */
1595		unsigned long nr_pages;	/* uncharged usage */
1596		unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
1597	} memcg_batch;
1598	unsigned int memcg_kmem_skip_account;
1599	struct memcg_oom_info {
1600		struct mem_cgroup *memcg;
1601		gfp_t gfp_mask;
1602		int order;
1603		unsigned int may_oom:1;
1604	} memcg_oom;
1605#endif
1606#ifdef CONFIG_UPROBES
1607	struct uprobe_task *utask;
1608#endif
1609#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1610	unsigned int	sequential_io;
1611	unsigned int	sequential_io_avg;
1612#endif
1613};
1614
1615/* Future-safe accessor for struct task_struct's cpus_allowed. */
1616#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
 
1617
1618#define TNF_MIGRATED	0x01
1619#define TNF_NO_GROUP	0x02
1620#define TNF_SHARED	0x04
1621#define TNF_FAULT_LOCAL	0x08
1622
1623#ifdef CONFIG_NUMA_BALANCING
1624extern void task_numa_fault(int last_node, int node, int pages, int flags);
1625extern pid_t task_numa_group_id(struct task_struct *p);
1626extern void set_numabalancing_state(bool enabled);
1627extern void task_numa_free(struct task_struct *p);
1628extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1629					int src_nid, int dst_cpu);
1630#else
1631static inline void task_numa_fault(int last_node, int node, int pages,
1632				   int flags)
1633{
1634}
1635static inline pid_t task_numa_group_id(struct task_struct *p)
1636{
1637	return 0;
1638}
1639static inline void set_numabalancing_state(bool enabled)
1640{
1641}
1642static inline void task_numa_free(struct task_struct *p)
1643{
1644}
1645static inline bool should_numa_migrate_memory(struct task_struct *p,
1646				struct page *page, int src_nid, int dst_cpu)
1647{
1648	return true;
1649}
1650#endif
1651
1652static inline struct pid *task_pid(struct task_struct *task)
1653{
1654	return task->pids[PIDTYPE_PID].pid;
1655}
1656
1657static inline struct pid *task_tgid(struct task_struct *task)
1658{
1659	return task->group_leader->pids[PIDTYPE_PID].pid;
1660}
1661
1662/*
1663 * Without tasklist or rcu lock it is not safe to dereference
1664 * the result of task_pgrp/task_session even if task == current,
1665 * we can race with another thread doing sys_setsid/sys_setpgid.
1666 */
1667static inline struct pid *task_pgrp(struct task_struct *task)
1668{
1669	return task->group_leader->pids[PIDTYPE_PGID].pid;
1670}
1671
1672static inline struct pid *task_session(struct task_struct *task)
1673{
1674	return task->group_leader->pids[PIDTYPE_SID].pid;
1675}
1676
1677struct pid_namespace;
 
1678
1679/*
1680 * the helpers to get the task's different pids as they are seen
1681 * from various namespaces
1682 *
1683 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1684 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1685 *                     current.
1686 * task_xid_nr_ns()  : id seen from the ns specified;
1687 *
1688 * set_task_vxid()   : assigns a virtual id to a task;
1689 *
1690 * see also pid_nr() etc in include/linux/pid.h
1691 */
1692pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1693			struct pid_namespace *ns);
1694
1695static inline pid_t task_pid_nr(struct task_struct *tsk)
1696{
1697	return tsk->pid;
1698}
1699
1700static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1701					struct pid_namespace *ns)
1702{
1703	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1704}
1705
1706static inline pid_t task_pid_vnr(struct task_struct *tsk)
1707{
1708	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1709}
1710
 
 
 
 
1711
1712static inline pid_t task_tgid_nr(struct task_struct *tsk)
1713{
1714	return tsk->tgid;
1715}
1716
1717pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
 
 
1718
1719static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1720{
1721	return pid_vnr(task_tgid(tsk));
1722}
1723
 
 
 
1724
1725static inline int pid_alive(const struct task_struct *p);
1726static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1727{
1728	pid_t pid = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1729
1730	rcu_read_lock();
1731	if (pid_alive(tsk))
1732		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1733	rcu_read_unlock();
1734
1735	return pid;
1736}
 
 
 
 
 
 
 
 
1737
1738static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1739{
1740	return task_ppid_nr_ns(tsk, &init_pid_ns);
1741}
 
 
1742
1743static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1744					struct pid_namespace *ns)
1745{
1746	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1747}
 
 
 
 
1748
1749static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1750{
1751	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1752}
 
 
 
 
 
1753
 
 
 
1754
1755static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1756					struct pid_namespace *ns)
1757{
1758	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1759}
1760
1761static inline pid_t task_session_vnr(struct task_struct *tsk)
1762{
1763	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1764}
1765
1766/* obsolete, do not use */
1767static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1768{
1769	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1770}
 
 
1771
1772/**
1773 * pid_alive - check that a task structure is not stale
1774 * @p: Task structure to be checked.
1775 *
1776 * Test if a process is not yet dead (at most zombie state)
1777 * If pid_alive fails, then pointers within the task structure
1778 * can be stale and must not be dereferenced.
1779 *
1780 * Return: 1 if the process is alive. 0 otherwise.
1781 */
1782static inline int pid_alive(const struct task_struct *p)
1783{
1784	return p->pids[PIDTYPE_PID].pid != NULL;
1785}
1786
1787/**
1788 * is_global_init - check if a task structure is init
1789 * @tsk: Task structure to be checked.
1790 *
1791 * Check if a task structure is the first user space task the kernel created.
1792 *
1793 * Return: 1 if the task structure is init. 0 otherwise.
1794 */
1795static inline int is_global_init(struct task_struct *tsk)
1796{
1797	return tsk->pid == 1;
1798}
1799
1800extern struct pid *cad_pid;
1801
1802extern void free_task(struct task_struct *tsk);
1803#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1804
1805extern void __put_task_struct(struct task_struct *t);
 
 
 
 
 
 
1806
1807static inline void put_task_struct(struct task_struct *t)
1808{
1809	if (atomic_dec_and_test(&t->usage))
1810		__put_task_struct(t);
1811}
1812
1813#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1814extern void task_cputime(struct task_struct *t,
1815			 cputime_t *utime, cputime_t *stime);
1816extern void task_cputime_scaled(struct task_struct *t,
1817				cputime_t *utimescaled, cputime_t *stimescaled);
1818extern cputime_t task_gtime(struct task_struct *t);
1819#else
1820static inline void task_cputime(struct task_struct *t,
1821				cputime_t *utime, cputime_t *stime)
1822{
1823	if (utime)
1824		*utime = t->utime;
1825	if (stime)
1826		*stime = t->stime;
1827}
1828
1829static inline void task_cputime_scaled(struct task_struct *t,
1830				       cputime_t *utimescaled,
1831				       cputime_t *stimescaled)
1832{
1833	if (utimescaled)
1834		*utimescaled = t->utimescaled;
1835	if (stimescaled)
1836		*stimescaled = t->stimescaled;
 
1837}
1838
1839static inline cputime_t task_gtime(struct task_struct *t)
1840{
1841	return t->gtime;
1842}
1843#endif
1844extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
1845extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
1846
1847/*
1848 * Per process flags
1849 */
1850#define PF_EXITING	0x00000004	/* getting shut down */
1851#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1852#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1853#define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
1854#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1855#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1856#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1857#define PF_DUMPCORE	0x00000200	/* dumped core */
1858#define PF_SIGNALED	0x00000400	/* killed by a signal */
1859#define PF_MEMALLOC	0x00000800	/* Allocating memory */
1860#define PF_NPROC_EXCEEDED 0x00001000	/* set_user noticed that RLIMIT_NPROC was exceeded */
1861#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1862#define PF_USED_ASYNC	0x00004000	/* used async_schedule*(), used by module init */
1863#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1864#define PF_FROZEN	0x00010000	/* frozen for system suspend */
1865#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1866#define PF_KSWAPD	0x00040000	/* I am kswapd */
1867#define PF_MEMALLOC_NOIO 0x00080000	/* Allocating memory without IO involved */
1868#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1869#define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1870#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1871#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1872#define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1873#define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1874#define PF_NO_SETAFFINITY 0x04000000	/* Userland is not allowed to meddle with cpus_allowed */
1875#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1876#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1877#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
1878#define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
 
 
 
 
1879
1880/*
1881 * Only the _current_ task can read/write to tsk->flags, but other
1882 * tasks can access tsk->flags in readonly mode for example
1883 * with tsk_used_math (like during threaded core dumping).
1884 * There is however an exception to this rule during ptrace
1885 * or during fork: the ptracer task is allowed to write to the
1886 * child->flags of its traced child (same goes for fork, the parent
1887 * can write to the child->flags), because we're guaranteed the
1888 * child is not running and in turn not changing child->flags
1889 * at the same time the parent does it.
1890 */
1891#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1892#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1893#define clear_used_math() clear_stopped_child_used_math(current)
1894#define set_used_math() set_stopped_child_used_math(current)
 
1895#define conditional_stopped_child_used_math(condition, child) \
1896	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1897#define conditional_used_math(condition) \
1898	conditional_stopped_child_used_math(condition, current)
1899#define copy_to_stopped_child_used_math(child) \
1900	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1901/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1902#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1903#define used_math() tsk_used_math(current)
1904
1905/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags */
1906static inline gfp_t memalloc_noio_flags(gfp_t flags)
1907{
1908	if (unlikely(current->flags & PF_MEMALLOC_NOIO))
1909		flags &= ~__GFP_IO;
1910	return flags;
1911}
1912
1913static inline unsigned int memalloc_noio_save(void)
1914{
1915	unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
1916	current->flags |= PF_MEMALLOC_NOIO;
1917	return flags;
1918}
1919
1920static inline void memalloc_noio_restore(unsigned int flags)
1921{
1922	current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
1923}
1924
1925/*
1926 * task->jobctl flags
1927 */
1928#define JOBCTL_STOP_SIGMASK	0xffff	/* signr of the last group stop */
1929
1930#define JOBCTL_STOP_DEQUEUED_BIT 16	/* stop signal dequeued */
1931#define JOBCTL_STOP_PENDING_BIT	17	/* task should stop for group stop */
1932#define JOBCTL_STOP_CONSUME_BIT	18	/* consume group stop count */
1933#define JOBCTL_TRAP_STOP_BIT	19	/* trap for STOP */
1934#define JOBCTL_TRAP_NOTIFY_BIT	20	/* trap for NOTIFY */
1935#define JOBCTL_TRAPPING_BIT	21	/* switching to TRACED */
1936#define JOBCTL_LISTENING_BIT	22	/* ptracer is listening for events */
1937
1938#define JOBCTL_STOP_DEQUEUED	(1 << JOBCTL_STOP_DEQUEUED_BIT)
1939#define JOBCTL_STOP_PENDING	(1 << JOBCTL_STOP_PENDING_BIT)
1940#define JOBCTL_STOP_CONSUME	(1 << JOBCTL_STOP_CONSUME_BIT)
1941#define JOBCTL_TRAP_STOP	(1 << JOBCTL_TRAP_STOP_BIT)
1942#define JOBCTL_TRAP_NOTIFY	(1 << JOBCTL_TRAP_NOTIFY_BIT)
1943#define JOBCTL_TRAPPING		(1 << JOBCTL_TRAPPING_BIT)
1944#define JOBCTL_LISTENING	(1 << JOBCTL_LISTENING_BIT)
1945
1946#define JOBCTL_TRAP_MASK	(JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
1947#define JOBCTL_PENDING_MASK	(JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
1948
1949extern bool task_set_jobctl_pending(struct task_struct *task,
1950				    unsigned int mask);
1951extern void task_clear_jobctl_trapping(struct task_struct *task);
1952extern void task_clear_jobctl_pending(struct task_struct *task,
1953				      unsigned int mask);
1954
1955#ifdef CONFIG_PREEMPT_RCU
1956
1957#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1958#define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */
 
1959
1960static inline void rcu_copy_process(struct task_struct *p)
1961{
1962	p->rcu_read_lock_nesting = 0;
1963	p->rcu_read_unlock_special = 0;
1964#ifdef CONFIG_TREE_PREEMPT_RCU
1965	p->rcu_blocked_node = NULL;
1966#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1967#ifdef CONFIG_RCU_BOOST
1968	p->rcu_boost_mutex = NULL;
1969#endif /* #ifdef CONFIG_RCU_BOOST */
1970	INIT_LIST_HEAD(&p->rcu_node_entry);
1971}
1972
1973#else
1974
1975static inline void rcu_copy_process(struct task_struct *p)
1976{
1977}
1978
1979#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1980
1981static inline void tsk_restore_flags(struct task_struct *task,
1982				unsigned long orig_flags, unsigned long flags)
 
 
 
1983{
1984	task->flags &= ~flags;
1985	task->flags |= orig_flags & flags;
1986}
1987
 
 
 
 
1988#ifdef CONFIG_SMP
1989extern void do_set_cpus_allowed(struct task_struct *p,
1990			       const struct cpumask *new_mask);
1991
1992extern int set_cpus_allowed_ptr(struct task_struct *p,
1993				const struct cpumask *new_mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1994#else
1995static inline void do_set_cpus_allowed(struct task_struct *p,
1996				      const struct cpumask *new_mask)
1997{
1998}
1999static inline int set_cpus_allowed_ptr(struct task_struct *p,
2000				       const struct cpumask *new_mask)
2001{
2002	if (!cpumask_test_cpu(0, new_mask))
2003		return -EINVAL;
2004	return 0;
2005}
2006#endif
2007
2008#ifdef CONFIG_NO_HZ_COMMON
2009void calc_load_enter_idle(void);
2010void calc_load_exit_idle(void);
2011#else
2012static inline void calc_load_enter_idle(void) { }
2013static inline void calc_load_exit_idle(void) { }
2014#endif /* CONFIG_NO_HZ_COMMON */
2015
2016#ifndef CONFIG_CPUMASK_OFFSTACK
2017static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
2018{
2019	return set_cpus_allowed_ptr(p, &new_mask);
2020}
2021#endif
2022
2023/*
2024 * Do not use outside of architecture code which knows its limitations.
2025 *
2026 * sched_clock() has no promise of monotonicity or bounded drift between
2027 * CPUs, use (which you should not) requires disabling IRQs.
2028 *
2029 * Please use one of the three interfaces below.
2030 */
2031extern unsigned long long notrace sched_clock(void);
2032/*
2033 * See the comment in kernel/sched/clock.c
2034 */
2035extern u64 cpu_clock(int cpu);
2036extern u64 local_clock(void);
2037extern u64 sched_clock_cpu(int cpu);
2038
2039
2040extern void sched_clock_init(void);
2041
2042#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2043static inline void sched_clock_tick(void)
2044{
 
 
 
2045}
2046
2047static inline void sched_clock_idle_sleep_event(void)
2048{
 
2049}
2050
2051static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2052{
 
2053}
2054#else
2055/*
2056 * Architectures can set this to 1 if they have specified
2057 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2058 * but then during bootup it turns out that sched_clock()
2059 * is reliable after all:
2060 */
2061extern int sched_clock_stable(void);
2062extern void set_sched_clock_stable(void);
2063extern void clear_sched_clock_stable(void);
2064
2065extern void sched_clock_tick(void);
2066extern void sched_clock_idle_sleep_event(void);
2067extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2068#endif
2069
2070#ifdef CONFIG_IRQ_TIME_ACCOUNTING
2071/*
2072 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2073 * The reason for this explicit opt-in is not to have perf penalty with
2074 * slow sched_clocks.
2075 */
2076extern void enable_sched_clock_irqtime(void);
2077extern void disable_sched_clock_irqtime(void);
2078#else
2079static inline void enable_sched_clock_irqtime(void) {}
2080static inline void disable_sched_clock_irqtime(void) {}
2081#endif
2082
2083extern unsigned long long
2084task_sched_runtime(struct task_struct *task);
2085
2086/* sched_exec is called by processes performing an exec */
2087#ifdef CONFIG_SMP
2088extern void sched_exec(void);
2089#else
2090#define sched_exec()   {}
2091#endif
2092
2093extern void sched_clock_idle_sleep_event(void);
2094extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2095
2096#ifdef CONFIG_HOTPLUG_CPU
2097extern void idle_task_exit(void);
2098#else
2099static inline void idle_task_exit(void) {}
2100#endif
2101
2102#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2103extern void wake_up_nohz_cpu(int cpu);
2104#else
2105static inline void wake_up_nohz_cpu(int cpu) { }
2106#endif
2107
2108#ifdef CONFIG_NO_HZ_FULL
2109extern bool sched_can_stop_tick(void);
2110extern u64 scheduler_tick_max_deferment(void);
2111#else
2112static inline bool sched_can_stop_tick(void) { return false; }
2113#endif
2114
2115#ifdef CONFIG_SCHED_AUTOGROUP
2116extern void sched_autogroup_create_attach(struct task_struct *p);
2117extern void sched_autogroup_detach(struct task_struct *p);
2118extern void sched_autogroup_fork(struct signal_struct *sig);
2119extern void sched_autogroup_exit(struct signal_struct *sig);
2120#ifdef CONFIG_PROC_FS
2121extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2122extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2123#endif
2124#else
2125static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2126static inline void sched_autogroup_detach(struct task_struct *p) { }
2127static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2128static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2129#endif
2130
2131extern bool yield_to(struct task_struct *p, bool preempt);
2132extern void set_user_nice(struct task_struct *p, long nice);
2133extern int task_prio(const struct task_struct *p);
 
2134/**
2135 * task_nice - return the nice value of a given task.
2136 * @p: the task in question.
2137 *
2138 * Return: The nice value [ -20 ... 0 ... 19 ].
2139 */
2140static inline int task_nice(const struct task_struct *p)
2141{
2142	return PRIO_TO_NICE((p)->static_prio);
2143}
 
2144extern int can_nice(const struct task_struct *p, const int nice);
2145extern int task_curr(const struct task_struct *p);
2146extern int idle_cpu(int cpu);
2147extern int sched_setscheduler(struct task_struct *, int,
2148			      const struct sched_param *);
2149extern int sched_setscheduler_nocheck(struct task_struct *, int,
2150				      const struct sched_param *);
2151extern int sched_setattr(struct task_struct *,
2152			 const struct sched_attr *);
 
 
2153extern struct task_struct *idle_task(int cpu);
 
2154/**
2155 * is_idle_task - is the specified task an idle task?
2156 * @p: the task in question.
2157 *
2158 * Return: 1 if @p is an idle task. 0 otherwise.
2159 */
2160static inline bool is_idle_task(const struct task_struct *p)
2161{
2162	return p->pid == 0;
2163}
 
2164extern struct task_struct *curr_task(int cpu);
2165extern void set_curr_task(int cpu, struct task_struct *p);
2166
2167void yield(void);
2168
2169/*
2170 * The default (Linux) execution domain.
2171 */
2172extern struct exec_domain	default_exec_domain;
2173
2174union thread_union {
 
 
2175	struct thread_info thread_info;
 
2176	unsigned long stack[THREAD_SIZE/sizeof(long)];
2177};
2178
2179#ifndef __HAVE_ARCH_KSTACK_END
2180static inline int kstack_end(void *addr)
2181{
2182	/* Reliable end of stack detection:
2183	 * Some APM bios versions misalign the stack
2184	 */
2185	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2186}
2187#endif
2188
2189extern union thread_union init_thread_union;
2190extern struct task_struct init_task;
2191
2192extern struct   mm_struct init_mm;
2193
2194extern struct pid_namespace init_pid_ns;
 
 
2195
2196/*
2197 * find a task by one of its numerical ids
2198 *
2199 * find_task_by_pid_ns():
2200 *      finds a task by its pid in the specified namespace
2201 * find_task_by_vpid():
2202 *      finds a task by its virtual pid
2203 *
2204 * see also find_vpid() etc in include/linux/pid.h
2205 */
2206
2207extern struct task_struct *find_task_by_vpid(pid_t nr);
2208extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2209		struct pid_namespace *ns);
2210
2211/* per-UID process charging. */
2212extern struct user_struct * alloc_uid(kuid_t);
2213static inline struct user_struct *get_uid(struct user_struct *u)
2214{
2215	atomic_inc(&u->__count);
2216	return u;
2217}
2218extern void free_uid(struct user_struct *);
2219
2220#include <asm/current.h>
2221
2222extern void xtime_update(unsigned long ticks);
 
 
 
2223
2224extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2225extern int wake_up_process(struct task_struct *tsk);
2226extern void wake_up_new_task(struct task_struct *tsk);
2227#ifdef CONFIG_SMP
2228 extern void kick_process(struct task_struct *tsk);
2229#else
2230 static inline void kick_process(struct task_struct *tsk) { }
2231#endif
2232extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2233extern void sched_dead(struct task_struct *p);
2234
2235extern void proc_caches_init(void);
2236extern void flush_signals(struct task_struct *);
2237extern void __flush_signals(struct task_struct *);
2238extern void ignore_signals(struct task_struct *);
2239extern void flush_signal_handlers(struct task_struct *, int force_default);
2240extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2241
2242static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2243{
2244	unsigned long flags;
2245	int ret;
2246
2247	spin_lock_irqsave(&tsk->sighand->siglock, flags);
2248	ret = dequeue_signal(tsk, mask, info);
2249	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2250
2251	return ret;
2252}
2253
2254extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2255			      sigset_t *mask);
2256extern void unblock_all_signals(void);
2257extern void release_task(struct task_struct * p);
2258extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2259extern int force_sigsegv(int, struct task_struct *);
2260extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2261extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2262extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2263extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2264				const struct cred *, u32);
2265extern int kill_pgrp(struct pid *pid, int sig, int priv);
2266extern int kill_pid(struct pid *pid, int sig, int priv);
2267extern int kill_proc_info(int, struct siginfo *, pid_t);
2268extern __must_check bool do_notify_parent(struct task_struct *, int);
2269extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2270extern void force_sig(int, struct task_struct *);
2271extern int send_sig(int, struct task_struct *, int);
2272extern int zap_other_threads(struct task_struct *p);
2273extern struct sigqueue *sigqueue_alloc(void);
2274extern void sigqueue_free(struct sigqueue *);
2275extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2276extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2277
2278static inline void restore_saved_sigmask(void)
2279{
2280	if (test_and_clear_restore_sigmask())
2281		__set_current_blocked(&current->saved_sigmask);
2282}
2283
2284static inline sigset_t *sigmask_to_save(void)
2285{
2286	sigset_t *res = &current->blocked;
2287	if (unlikely(test_restore_sigmask()))
2288		res = &current->saved_sigmask;
2289	return res;
2290}
2291
2292static inline int kill_cad_pid(int sig, int priv)
2293{
2294	return kill_pid(cad_pid, sig, priv);
2295}
2296
2297/* These can be the second arg to send_sig_info/send_group_sig_info.  */
2298#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2299#define SEND_SIG_PRIV	((struct siginfo *) 1)
2300#define SEND_SIG_FORCED	((struct siginfo *) 2)
2301
2302/*
2303 * True if we are on the alternate signal stack.
2304 */
2305static inline int on_sig_stack(unsigned long sp)
2306{
2307#ifdef CONFIG_STACK_GROWSUP
2308	return sp >= current->sas_ss_sp &&
2309		sp - current->sas_ss_sp < current->sas_ss_size;
2310#else
2311	return sp > current->sas_ss_sp &&
2312		sp - current->sas_ss_sp <= current->sas_ss_size;
2313#endif
2314}
2315
2316static inline int sas_ss_flags(unsigned long sp)
2317{
2318	return (current->sas_ss_size == 0 ? SS_DISABLE
2319		: on_sig_stack(sp) ? SS_ONSTACK : 0);
2320}
2321
2322static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2323{
2324	if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2325#ifdef CONFIG_STACK_GROWSUP
2326		return current->sas_ss_sp;
2327#else
2328		return current->sas_ss_sp + current->sas_ss_size;
2329#endif
2330	return sp;
2331}
2332
2333/*
2334 * Routines for handling mm_structs
2335 */
2336extern struct mm_struct * mm_alloc(void);
 
2337
2338/* mmdrop drops the mm and the page tables */
2339extern void __mmdrop(struct mm_struct *);
2340static inline void mmdrop(struct mm_struct * mm)
2341{
2342	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2343		__mmdrop(mm);
 
 
 
 
2344}
2345
2346/* mmput gets rid of the mappings and all user-space */
2347extern void mmput(struct mm_struct *);
2348/* Grab a reference to a task's mm, if it is not already going away */
2349extern struct mm_struct *get_task_mm(struct task_struct *task);
2350/*
2351 * Grab a reference to a task's mm, if it is not already going away
2352 * and ptrace_may_access with the mode parameter passed to it
2353 * succeeds.
2354 */
2355extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2356/* Remove the current tasks stale references to the old mm_struct */
2357extern void mm_release(struct task_struct *, struct mm_struct *);
2358
2359extern int copy_thread(unsigned long, unsigned long, unsigned long,
2360			struct task_struct *);
2361extern void flush_thread(void);
2362extern void exit_thread(void);
2363
2364extern void exit_files(struct task_struct *);
2365extern void __cleanup_sighand(struct sighand_struct *);
2366
2367extern void exit_itimers(struct signal_struct *);
2368extern void flush_itimer_signals(void);
2369
2370extern void do_group_exit(int);
2371
2372extern int allow_signal(int);
2373extern int disallow_signal(int);
2374
2375extern int do_execve(struct filename *,
2376		     const char __user * const __user *,
2377		     const char __user * const __user *);
2378extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2379struct task_struct *fork_idle(int);
2380extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2381
2382extern void set_task_comm(struct task_struct *tsk, const char *from);
2383extern char *get_task_comm(char *to, struct task_struct *tsk);
2384
2385#ifdef CONFIG_SMP
2386void scheduler_ipi(void);
2387extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2388#else
2389static inline void scheduler_ipi(void) { }
2390static inline unsigned long wait_task_inactive(struct task_struct *p,
2391					       long match_state)
2392{
2393	return 1;
2394}
2395#endif
2396
2397#define next_task(p) \
2398	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2399
2400#define for_each_process(p) \
2401	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2402
2403extern bool current_is_single_threaded(void);
2404
2405/*
2406 * Careful: do_each_thread/while_each_thread is a double loop so
2407 *          'break' will not work as expected - use goto instead.
2408 */
2409#define do_each_thread(g, t) \
2410	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2411
2412#define while_each_thread(g, t) \
2413	while ((t = next_thread(t)) != g)
2414
2415#define __for_each_thread(signal, t)	\
2416	list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2417
2418#define for_each_thread(p, t)		\
2419	__for_each_thread((p)->signal, t)
2420
2421/* Careful: this is a double loop, 'break' won't work as expected. */
2422#define for_each_process_thread(p, t)	\
2423	for_each_process(p) for_each_thread(p, t)
2424
2425static inline int get_nr_threads(struct task_struct *tsk)
2426{
2427	return tsk->signal->nr_threads;
2428}
2429
2430static inline bool thread_group_leader(struct task_struct *p)
2431{
2432	return p->exit_signal >= 0;
2433}
2434
2435/* Do to the insanities of de_thread it is possible for a process
2436 * to have the pid of the thread group leader without actually being
2437 * the thread group leader.  For iteration through the pids in proc
2438 * all we care about is that we have a task with the appropriate
2439 * pid, we don't actually care if we have the right task.
2440 */
2441static inline bool has_group_leader_pid(struct task_struct *p)
2442{
2443	return task_pid(p) == p->signal->leader_pid;
2444}
2445
2446static inline
2447bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2448{
2449	return p1->signal == p2->signal;
2450}
2451
2452static inline struct task_struct *next_thread(const struct task_struct *p)
2453{
2454	return list_entry_rcu(p->thread_group.next,
2455			      struct task_struct, thread_group);
2456}
2457
2458static inline int thread_group_empty(struct task_struct *p)
2459{
2460	return list_empty(&p->thread_group);
2461}
2462
2463#define delay_group_leader(p) \
2464		(thread_group_leader(p) && !thread_group_empty(p))
2465
2466/*
2467 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2468 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2469 * pins the final release of task.io_context.  Also protects ->cpuset and
2470 * ->cgroup.subsys[]. And ->vfork_done.
2471 *
2472 * Nests both inside and outside of read_lock(&tasklist_lock).
2473 * It must not be nested with write_lock_irq(&tasklist_lock),
2474 * neither inside nor outside.
2475 */
2476static inline void task_lock(struct task_struct *p)
2477{
2478	spin_lock(&p->alloc_lock);
2479}
2480
2481static inline void task_unlock(struct task_struct *p)
2482{
2483	spin_unlock(&p->alloc_lock);
2484}
2485
2486extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2487							unsigned long *flags);
2488
2489static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2490						       unsigned long *flags)
2491{
2492	struct sighand_struct *ret;
2493
2494	ret = __lock_task_sighand(tsk, flags);
2495	(void)__cond_lock(&tsk->sighand->siglock, ret);
2496	return ret;
2497}
2498
2499static inline void unlock_task_sighand(struct task_struct *tsk,
2500						unsigned long *flags)
2501{
2502	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2503}
2504
2505#ifdef CONFIG_CGROUPS
2506static inline void threadgroup_change_begin(struct task_struct *tsk)
2507{
2508	down_read(&tsk->signal->group_rwsem);
2509}
2510static inline void threadgroup_change_end(struct task_struct *tsk)
2511{
2512	up_read(&tsk->signal->group_rwsem);
2513}
2514
2515/**
2516 * threadgroup_lock - lock threadgroup
2517 * @tsk: member task of the threadgroup to lock
2518 *
2519 * Lock the threadgroup @tsk belongs to.  No new task is allowed to enter
2520 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or
2521 * change ->group_leader/pid.  This is useful for cases where the threadgroup
2522 * needs to stay stable across blockable operations.
2523 *
2524 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for
2525 * synchronization.  While held, no new task will be added to threadgroup
2526 * and no existing live task will have its PF_EXITING set.
2527 *
2528 * de_thread() does threadgroup_change_{begin|end}() when a non-leader
2529 * sub-thread becomes a new leader.
2530 */
2531static inline void threadgroup_lock(struct task_struct *tsk)
2532{
2533	down_write(&tsk->signal->group_rwsem);
2534}
2535
2536/**
2537 * threadgroup_unlock - unlock threadgroup
2538 * @tsk: member task of the threadgroup to unlock
2539 *
2540 * Reverse threadgroup_lock().
2541 */
2542static inline void threadgroup_unlock(struct task_struct *tsk)
2543{
2544	up_write(&tsk->signal->group_rwsem);
2545}
2546#else
2547static inline void threadgroup_change_begin(struct task_struct *tsk) {}
2548static inline void threadgroup_change_end(struct task_struct *tsk) {}
2549static inline void threadgroup_lock(struct task_struct *tsk) {}
2550static inline void threadgroup_unlock(struct task_struct *tsk) {}
2551#endif
2552
2553#ifndef __HAVE_THREAD_FUNCTIONS
2554
2555#define task_thread_info(task)	((struct thread_info *)(task)->stack)
2556#define task_stack_page(task)	((task)->stack)
2557
2558static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2559{
2560	*task_thread_info(p) = *task_thread_info(org);
2561	task_thread_info(p)->task = p;
2562}
2563
2564static inline unsigned long *end_of_stack(struct task_struct *p)
2565{
2566	return (unsigned long *)(task_thread_info(p) + 1);
2567}
2568
2569#endif
2570
2571static inline int object_is_on_stack(void *obj)
2572{
2573	void *stack = task_stack_page(current);
2574
2575	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2576}
2577
2578extern void thread_info_cache_init(void);
2579
2580#ifdef CONFIG_DEBUG_STACK_USAGE
2581static inline unsigned long stack_not_used(struct task_struct *p)
2582{
2583	unsigned long *n = end_of_stack(p);
2584
2585	do { 	/* Skip over canary */
2586		n++;
2587	} while (!*n);
2588
2589	return (unsigned long)n - (unsigned long)end_of_stack(p);
2590}
2591#endif
2592
2593/* set thread flags in other task's structures
2594 * - see asm/thread_info.h for TIF_xxxx flags available
2595 */
2596static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2597{
2598	set_ti_thread_flag(task_thread_info(tsk), flag);
2599}
2600
2601static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2602{
2603	clear_ti_thread_flag(task_thread_info(tsk), flag);
2604}
2605
 
 
 
 
 
 
2606static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2607{
2608	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2609}
2610
2611static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2612{
2613	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2614}
2615
2616static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2617{
2618	return test_ti_thread_flag(task_thread_info(tsk), flag);
2619}
2620
2621static inline void set_tsk_need_resched(struct task_struct *tsk)
2622{
2623	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2624}
2625
2626static inline void clear_tsk_need_resched(struct task_struct *tsk)
2627{
2628	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2629}
2630
2631static inline int test_tsk_need_resched(struct task_struct *tsk)
2632{
2633	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2634}
2635
2636static inline int restart_syscall(void)
2637{
2638	set_tsk_thread_flag(current, TIF_SIGPENDING);
2639	return -ERESTARTNOINTR;
2640}
2641
2642static inline int signal_pending(struct task_struct *p)
2643{
2644	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2645}
2646
2647static inline int __fatal_signal_pending(struct task_struct *p)
2648{
2649	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2650}
2651
2652static inline int fatal_signal_pending(struct task_struct *p)
2653{
2654	return signal_pending(p) && __fatal_signal_pending(p);
2655}
2656
2657static inline int signal_pending_state(long state, struct task_struct *p)
2658{
2659	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2660		return 0;
2661	if (!signal_pending(p))
2662		return 0;
2663
2664	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2665}
2666
2667/*
2668 * cond_resched() and cond_resched_lock(): latency reduction via
2669 * explicit rescheduling in places that are safe. The return
2670 * value indicates whether a reschedule was done in fact.
2671 * cond_resched_lock() will drop the spinlock before scheduling,
2672 * cond_resched_softirq() will enable bhs before scheduling.
2673 */
2674extern int _cond_resched(void);
 
2675
2676#define cond_resched() ({			\
2677	__might_sleep(__FILE__, __LINE__, 0);	\
2678	_cond_resched();			\
2679})
2680
2681extern int __cond_resched_lock(spinlock_t *lock);
 
2682
2683#ifdef CONFIG_PREEMPT_COUNT
2684#define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2685#else
2686#define PREEMPT_LOCK_OFFSET	0
2687#endif
2688
2689#define cond_resched_lock(lock) ({				\
2690	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2691	__cond_resched_lock(lock);				\
2692})
2693
2694extern int __cond_resched_softirq(void);
2695
2696#define cond_resched_softirq() ({					\
2697	__might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2698	__cond_resched_softirq();					\
2699})
2700
2701static inline void cond_resched_rcu(void)
2702{
2703#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2704	rcu_read_unlock();
2705	cond_resched();
2706	rcu_read_lock();
2707#endif
2708}
2709
2710/*
2711 * Does a critical section need to be broken due to another
2712 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2713 * but a general need for low latency)
2714 */
2715static inline int spin_needbreak(spinlock_t *lock)
2716{
2717#ifdef CONFIG_PREEMPT
2718	return spin_is_contended(lock);
2719#else
2720	return 0;
2721#endif
2722}
2723
2724/*
2725 * Idle thread specific functions to determine the need_resched
2726 * polling state. We have two versions, one based on TS_POLLING in
2727 * thread_info.status and one based on TIF_POLLING_NRFLAG in
2728 * thread_info.flags
2729 */
2730#ifdef TS_POLLING
2731static inline int tsk_is_polling(struct task_struct *p)
2732{
2733	return task_thread_info(p)->status & TS_POLLING;
2734}
2735static inline void __current_set_polling(void)
2736{
2737	current_thread_info()->status |= TS_POLLING;
 
2738}
2739
2740static inline bool __must_check current_set_polling_and_test(void)
2741{
2742	__current_set_polling();
2743
2744	/*
2745	 * Polling state must be visible before we test NEED_RESCHED,
2746	 * paired by resched_task()
2747	 */
2748	smp_mb();
2749
2750	return unlikely(tif_need_resched());
2751}
2752
2753static inline void __current_clr_polling(void)
2754{
2755	current_thread_info()->status &= ~TS_POLLING;
 
2756}
2757
2758static inline bool __must_check current_clr_polling_and_test(void)
2759{
2760	__current_clr_polling();
2761
2762	/*
2763	 * Polling state must be visible before we test NEED_RESCHED,
2764	 * paired by resched_task()
2765	 */
2766	smp_mb();
2767
2768	return unlikely(tif_need_resched());
2769}
2770#elif defined(TIF_POLLING_NRFLAG)
2771static inline int tsk_is_polling(struct task_struct *p)
2772{
2773	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2774}
2775
2776static inline void __current_set_polling(void)
2777{
2778	set_thread_flag(TIF_POLLING_NRFLAG);
2779}
2780
2781static inline bool __must_check current_set_polling_and_test(void)
2782{
2783	__current_set_polling();
2784
2785	/*
2786	 * Polling state must be visible before we test NEED_RESCHED,
2787	 * paired by resched_task()
2788	 *
2789	 * XXX: assumes set/clear bit are identical barrier wise.
2790	 */
2791	smp_mb__after_clear_bit();
 
 
 
 
 
 
 
 
2792
2793	return unlikely(tif_need_resched());
2794}
 
 
2795
2796static inline void __current_clr_polling(void)
2797{
2798	clear_thread_flag(TIF_POLLING_NRFLAG);
2799}
2800
2801static inline bool __must_check current_clr_polling_and_test(void)
2802{
2803	__current_clr_polling();
 
2804
2805	/*
2806	 * Polling state must be visible before we test NEED_RESCHED,
2807	 * paired by resched_task()
2808	 */
2809	smp_mb__after_clear_bit();
2810
2811	return unlikely(tif_need_resched());
2812}
 
2813
2814#else
2815static inline int tsk_is_polling(struct task_struct *p) { return 0; }
2816static inline void __current_set_polling(void) { }
2817static inline void __current_clr_polling(void) { }
2818
2819static inline bool __must_check current_set_polling_and_test(void)
2820{
2821	return unlikely(tif_need_resched());
2822}
2823static inline bool __must_check current_clr_polling_and_test(void)
2824{
2825	return unlikely(tif_need_resched());
2826}
2827#endif
2828
2829static inline void current_clr_polling(void)
2830{
2831	__current_clr_polling();
2832
2833	/*
2834	 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
2835	 * Once the bit is cleared, we'll get IPIs with every new
2836	 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
2837	 * fold.
2838	 */
2839	smp_mb(); /* paired with resched_task() */
2840
2841	preempt_fold_need_resched();
2842}
2843
2844static __always_inline bool need_resched(void)
2845{
2846	return unlikely(tif_need_resched());
2847}
2848
2849/*
2850 * Thread group CPU time accounting.
2851 */
2852void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2853void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2854
2855static inline void thread_group_cputime_init(struct signal_struct *sig)
2856{
2857	raw_spin_lock_init(&sig->cputimer.lock);
2858}
2859
2860/*
2861 * Reevaluate whether the task has signals pending delivery.
2862 * Wake the task if so.
2863 * This is required every time the blocked sigset_t changes.
2864 * callers must hold sighand->siglock.
 
 
2865 */
2866extern void recalc_sigpending_and_wake(struct task_struct *t);
2867extern void recalc_sigpending(void);
2868
2869extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
2870
2871static inline void signal_wake_up(struct task_struct *t, bool resume)
2872{
2873	signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
2874}
2875static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
 
2876{
2877	signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
2878}
2879
2880/*
2881 * Wrappers for p->thread_info->cpu access. No-op on UP.
2882 */
2883#ifdef CONFIG_SMP
2884
2885static inline unsigned int task_cpu(const struct task_struct *p)
2886{
2887	return task_thread_info(p)->cpu;
2888}
2889
2890static inline int task_node(const struct task_struct *p)
2891{
2892	return cpu_to_node(task_cpu(p));
2893}
2894
2895extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2896
2897#else
2898
2899static inline unsigned int task_cpu(const struct task_struct *p)
2900{
2901	return 0;
2902}
2903
2904static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2905{
2906}
2907
2908#endif /* CONFIG_SMP */
2909
2910extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2911extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2912
2913#ifdef CONFIG_CGROUP_SCHED
2914extern struct task_group root_task_group;
2915#endif /* CONFIG_CGROUP_SCHED */
2916
2917extern int task_can_switch_user(struct user_struct *up,
2918					struct task_struct *tsk);
2919
2920#ifdef CONFIG_TASK_XACCT
2921static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2922{
2923	tsk->ioac.rchar += amt;
2924}
2925
2926static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2927{
2928	tsk->ioac.wchar += amt;
2929}
2930
2931static inline void inc_syscr(struct task_struct *tsk)
2932{
2933	tsk->ioac.syscr++;
2934}
2935
2936static inline void inc_syscw(struct task_struct *tsk)
2937{
2938	tsk->ioac.syscw++;
2939}
2940#else
2941static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2942{
2943}
2944
2945static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2946{
2947}
2948
2949static inline void inc_syscr(struct task_struct *tsk)
2950{
2951}
2952
2953static inline void inc_syscw(struct task_struct *tsk)
 
 
 
 
 
 
 
 
 
2954{
 
2955}
2956#endif
2957
 
 
 
2958#ifndef TASK_SIZE_OF
2959#define TASK_SIZE_OF(tsk)	TASK_SIZE
2960#endif
2961
2962#ifdef CONFIG_MM_OWNER
2963extern void mm_update_next_owner(struct mm_struct *mm);
2964extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2965#else
2966static inline void mm_update_next_owner(struct mm_struct *mm)
2967{
2968}
2969
2970static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2971{
2972}
2973#endif /* CONFIG_MM_OWNER */
2974
2975static inline unsigned long task_rlimit(const struct task_struct *tsk,
2976		unsigned int limit)
2977{
2978	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
 
 
 
 
2979}
2980
2981static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2982		unsigned int limit)
2983{
2984	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2985}
2986
2987static inline unsigned long rlimit(unsigned int limit)
2988{
2989	return task_rlimit(current, limit);
2990}
 
 
 
 
 
 
 
2991
2992static inline unsigned long rlimit_max(unsigned int limit)
2993{
2994	return task_rlimit_max(current, limit);
2995}
2996
2997#endif
v6.8
   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_SCHED_H
   3#define _LINUX_SCHED_H
   4
   5/*
   6 * Define 'struct task_struct' and provide the main scheduler
   7 * APIs (schedule(), wakeup variants, etc.)
   8 */
 
 
 
 
   9
  10#include <uapi/linux/sched.h>
  11
  12#include <asm/current.h>
  13#include <asm/processor.h>
 
 
 
 
 
 
  14#include <linux/thread_info.h>
  15#include <linux/preempt.h>
  16#include <linux/cpumask.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  17
  18#include <linux/cache.h>
  19#include <linux/irqflags_types.h>
  20#include <linux/smp_types.h>
  21#include <linux/pid_types.h>
  22#include <linux/sem_types.h>
  23#include <linux/shm.h>
  24#include <linux/kmsan_types.h>
  25#include <linux/mutex_types.h>
  26#include <linux/plist_types.h>
  27#include <linux/hrtimer_types.h>
  28#include <linux/timer_types.h>
  29#include <linux/seccomp_types.h>
  30#include <linux/nodemask_types.h>
  31#include <linux/refcount_types.h>
  32#include <linux/resource.h>
 
 
 
  33#include <linux/latencytop.h>
  34#include <linux/sched/prio.h>
  35#include <linux/sched/types.h>
  36#include <linux/signal_types.h>
  37#include <linux/syscall_user_dispatch_types.h>
  38#include <linux/mm_types_task.h>
  39#include <linux/task_io_accounting.h>
  40#include <linux/posix-timers_types.h>
  41#include <linux/restart_block.h>
  42#include <uapi/linux/rseq.h>
  43#include <linux/seqlock_types.h>
  44#include <linux/kcsan.h>
  45#include <linux/rv.h>
  46#include <linux/livepatch_sched.h>
  47#include <linux/uidgid_types.h>
  48#include <asm/kmap_size.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  49
  50/* task_struct member predeclarations (sorted alphabetically): */
  51struct audit_context;
 
  52struct bio_list;
  53struct blk_plug;
  54struct bpf_local_storage;
  55struct bpf_run_ctx;
  56struct capture_control;
  57struct cfs_rq;
  58struct fs_struct;
  59struct futex_pi_state;
  60struct io_context;
  61struct io_uring_task;
  62struct mempolicy;
  63struct nameidata;
  64struct nsproxy;
  65struct perf_event_context;
  66struct pid_namespace;
  67struct pipe_inode_info;
  68struct rcu_node;
  69struct reclaim_state;
  70struct robust_list_head;
  71struct root_domain;
  72struct rq;
  73struct sched_attr;
  74struct sched_dl_entity;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  75struct seq_file;
  76struct sighand_struct;
  77struct signal_struct;
  78struct task_delay_info;
  79struct task_group;
  80struct task_struct;
  81struct user_event_mm;
 
 
 
 
  82
  83/*
  84 * Task state bitmask. NOTE! These bits are also
  85 * encoded in fs/proc/array.c: get_task_state().
  86 *
  87 * We have two separate sets of flags: task->__state
  88 * is about runnability, while task->exit_state are
  89 * about the task exiting. Confusing, but this way
  90 * modifying one set can't modify the other one by
  91 * mistake.
  92 */
  93
  94/* Used in tsk->__state: */
  95#define TASK_RUNNING			0x00000000
  96#define TASK_INTERRUPTIBLE		0x00000001
  97#define TASK_UNINTERRUPTIBLE		0x00000002
  98#define __TASK_STOPPED			0x00000004
  99#define __TASK_TRACED			0x00000008
 100/* Used in tsk->exit_state: */
 101#define EXIT_DEAD			0x00000010
 102#define EXIT_ZOMBIE			0x00000020
 103#define EXIT_TRACE			(EXIT_ZOMBIE | EXIT_DEAD)
 104/* Used in tsk->__state again: */
 105#define TASK_PARKED			0x00000040
 106#define TASK_DEAD			0x00000080
 107#define TASK_WAKEKILL			0x00000100
 108#define TASK_WAKING			0x00000200
 109#define TASK_NOLOAD			0x00000400
 110#define TASK_NEW			0x00000800
 111#define TASK_RTLOCK_WAIT		0x00001000
 112#define TASK_FREEZABLE			0x00002000
 113#define __TASK_FREEZABLE_UNSAFE	       (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP))
 114#define TASK_FROZEN			0x00008000
 115#define TASK_STATE_MAX			0x00010000
 116
 117#define TASK_ANY			(TASK_STATE_MAX-1)
 118
 119/*
 120 * DO NOT ADD ANY NEW USERS !
 121 */
 122#define TASK_FREEZABLE_UNSAFE		(TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE)
 123
 124/* Convenience macros for the sake of set_current_state: */
 125#define TASK_KILLABLE			(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
 126#define TASK_STOPPED			(TASK_WAKEKILL | __TASK_STOPPED)
 127#define TASK_TRACED			__TASK_TRACED
 128
 129#define TASK_IDLE			(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
 130
 131/* Convenience macros for the sake of wake_up(): */
 132#define TASK_NORMAL			(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
 133
 134/* get_task_state(): */
 135#define TASK_REPORT			(TASK_RUNNING | TASK_INTERRUPTIBLE | \
 136					 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
 137					 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
 138					 TASK_PARKED)
 139
 140#define task_is_running(task)		(READ_ONCE((task)->__state) == TASK_RUNNING)
 141
 142#define task_is_traced(task)		((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0)
 143#define task_is_stopped(task)		((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0)
 144#define task_is_stopped_or_traced(task)	((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0)
 145
 146/*
 147 * Special states are those that do not use the normal wait-loop pattern. See
 148 * the comment with set_special_state().
 149 */
 150#define is_special_task_state(state)				\
 151	((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
 152
 153#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 154# define debug_normal_state_change(state_value)				\
 155	do {								\
 156		WARN_ON_ONCE(is_special_task_state(state_value));	\
 157		current->task_state_change = _THIS_IP_;			\
 158	} while (0)
 159
 160# define debug_special_state_change(state_value)			\
 161	do {								\
 162		WARN_ON_ONCE(!is_special_task_state(state_value));	\
 163		current->task_state_change = _THIS_IP_;			\
 164	} while (0)
 165
 166# define debug_rtlock_wait_set_state()					\
 167	do {								 \
 168		current->saved_state_change = current->task_state_change;\
 169		current->task_state_change = _THIS_IP_;			 \
 170	} while (0)
 171
 172# define debug_rtlock_wait_restore_state()				\
 173	do {								 \
 174		current->task_state_change = current->saved_state_change;\
 175	} while (0)
 176
 177#else
 178# define debug_normal_state_change(cond)	do { } while (0)
 179# define debug_special_state_change(cond)	do { } while (0)
 180# define debug_rtlock_wait_set_state()		do { } while (0)
 181# define debug_rtlock_wait_restore_state()	do { } while (0)
 182#endif
 183
 184/*
 185 * set_current_state() includes a barrier so that the write of current->__state
 186 * is correctly serialised wrt the caller's subsequent test of whether to
 187 * actually sleep:
 188 *
 189 *   for (;;) {
 190 *	set_current_state(TASK_UNINTERRUPTIBLE);
 191 *	if (CONDITION)
 192 *	   break;
 193 *
 194 *	schedule();
 195 *   }
 196 *   __set_current_state(TASK_RUNNING);
 197 *
 198 * If the caller does not need such serialisation (because, for instance, the
 199 * CONDITION test and condition change and wakeup are under the same lock) then
 200 * use __set_current_state().
 201 *
 202 * The above is typically ordered against the wakeup, which does:
 203 *
 204 *   CONDITION = 1;
 205 *   wake_up_state(p, TASK_UNINTERRUPTIBLE);
 206 *
 207 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
 208 * accessing p->__state.
 209 *
 210 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is,
 211 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
 212 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
 213 *
 214 * However, with slightly different timing the wakeup TASK_RUNNING store can
 215 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
 216 * a problem either because that will result in one extra go around the loop
 217 * and our @cond test will save the day.
 218 *
 219 * Also see the comments of try_to_wake_up().
 220 */
 221#define __set_current_state(state_value)				\
 222	do {								\
 223		debug_normal_state_change((state_value));		\
 224		WRITE_ONCE(current->__state, (state_value));		\
 225	} while (0)
 226
 227#define set_current_state(state_value)					\
 228	do {								\
 229		debug_normal_state_change((state_value));		\
 230		smp_store_mb(current->__state, (state_value));		\
 231	} while (0)
 232
 233/*
 234 * set_special_state() should be used for those states when the blocking task
 235 * can not use the regular condition based wait-loop. In that case we must
 236 * serialize against wakeups such that any possible in-flight TASK_RUNNING
 237 * stores will not collide with our state change.
 238 */
 239#define set_special_state(state_value)					\
 240	do {								\
 241		unsigned long flags; /* may shadow */			\
 242									\
 243		raw_spin_lock_irqsave(&current->pi_lock, flags);	\
 244		debug_special_state_change((state_value));		\
 245		WRITE_ONCE(current->__state, (state_value));		\
 246		raw_spin_unlock_irqrestore(&current->pi_lock, flags);	\
 247	} while (0)
 248
 249/*
 250 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
 251 *
 252 * RT's spin/rwlock substitutions are state preserving. The state of the
 253 * task when blocking on the lock is saved in task_struct::saved_state and
 254 * restored after the lock has been acquired.  These operations are
 255 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
 256 * lock related wakeups while the task is blocked on the lock are
 257 * redirected to operate on task_struct::saved_state to ensure that these
 258 * are not dropped. On restore task_struct::saved_state is set to
 259 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
 260 *
 261 * The lock operation looks like this:
 262 *
 263 *	current_save_and_set_rtlock_wait_state();
 264 *	for (;;) {
 265 *		if (try_lock())
 266 *			break;
 267 *		raw_spin_unlock_irq(&lock->wait_lock);
 268 *		schedule_rtlock();
 269 *		raw_spin_lock_irq(&lock->wait_lock);
 270 *		set_current_state(TASK_RTLOCK_WAIT);
 271 *	}
 272 *	current_restore_rtlock_saved_state();
 273 */
 274#define current_save_and_set_rtlock_wait_state()			\
 275	do {								\
 276		lockdep_assert_irqs_disabled();				\
 277		raw_spin_lock(&current->pi_lock);			\
 278		current->saved_state = current->__state;		\
 279		debug_rtlock_wait_set_state();				\
 280		WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT);		\
 281		raw_spin_unlock(&current->pi_lock);			\
 282	} while (0);
 283
 284#define current_restore_rtlock_saved_state()				\
 285	do {								\
 286		lockdep_assert_irqs_disabled();				\
 287		raw_spin_lock(&current->pi_lock);			\
 288		debug_rtlock_wait_restore_state();			\
 289		WRITE_ONCE(current->__state, current->saved_state);	\
 290		current->saved_state = TASK_RUNNING;			\
 291		raw_spin_unlock(&current->pi_lock);			\
 292	} while (0);
 293
 294#define get_current_state()	READ_ONCE(current->__state)
 
 
 
 295
 296/*
 297 * Define the task command name length as enum, then it can be visible to
 298 * BPF programs.
 
 
 299 */
 300enum {
 301	TASK_COMM_LEN = 16,
 302};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 303
 
 
 
 304extern void scheduler_tick(void);
 305
 306#define	MAX_SCHEDULE_TIMEOUT		LONG_MAX
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 307
 308extern long schedule_timeout(long timeout);
 309extern long schedule_timeout_interruptible(long timeout);
 310extern long schedule_timeout_killable(long timeout);
 311extern long schedule_timeout_uninterruptible(long timeout);
 312extern long schedule_timeout_idle(long timeout);
 
 
 
 313asmlinkage void schedule(void);
 314extern void schedule_preempt_disabled(void);
 315asmlinkage void preempt_schedule_irq(void);
 316#ifdef CONFIG_PREEMPT_RT
 317 extern void schedule_rtlock(void);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 318#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 319
 320extern int __must_check io_schedule_prepare(void);
 321extern void io_schedule_finish(int token);
 322extern long io_schedule_timeout(long timeout);
 323extern void io_schedule(void);
 
 
 324
 325/**
 326 * struct prev_cputime - snapshot of system and user cputime
 327 * @utime: time spent in user mode
 328 * @stime: time spent in system mode
 329 * @lock: protects the above two fields
 330 *
 331 * Stores previous user/system time values such that we can guarantee
 332 * monotonicity.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 333 */
 334struct prev_cputime {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 335#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 336	u64				utime;
 337	u64				stime;
 338	raw_spinlock_t			lock;
 339#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 340};
 341
 342enum vtime_state {
 343	/* Task is sleeping or running in a CPU with VTIME inactive: */
 344	VTIME_INACTIVE = 0,
 345	/* Task is idle */
 346	VTIME_IDLE,
 347	/* Task runs in kernelspace in a CPU with VTIME active: */
 348	VTIME_SYS,
 349	/* Task runs in userspace in a CPU with VTIME active: */
 350	VTIME_USER,
 351	/* Task runs as guests in a CPU with VTIME active: */
 352	VTIME_GUEST,
 353};
 354
 355struct vtime {
 356	seqcount_t		seqcount;
 357	unsigned long long	starttime;
 358	enum vtime_state	state;
 359	unsigned int		cpu;
 360	u64			utime;
 361	u64			stime;
 362	u64			gtime;
 363};
 364
 365/*
 366 * Utilization clamp constraints.
 367 * @UCLAMP_MIN:	Minimum utilization
 368 * @UCLAMP_MAX:	Maximum utilization
 369 * @UCLAMP_CNT:	Utilization clamp constraints count
 370 */
 371enum uclamp_id {
 372	UCLAMP_MIN = 0,
 373	UCLAMP_MAX,
 374	UCLAMP_CNT
 375};
 
 
 
 
 
 
 
 
 
 
 
 
 376
 377#ifdef CONFIG_SMP
 378extern struct root_domain def_root_domain;
 379extern struct mutex sched_domains_mutex;
 380#endif
 381
 382struct sched_param {
 383	int sched_priority;
 
 
 
 
 
 384};
 385
 
 
 
 
 
 
 
 
 
 
 
 
 386struct sched_info {
 387#ifdef CONFIG_SCHED_INFO
 388	/* Cumulative counters: */
 
 
 
 
 
 
 
 389
 390	/* # of times we have run on this CPU: */
 391	unsigned long			pcount;
 
 
 392
 393	/* Time spent waiting on a runqueue: */
 394	unsigned long long		run_delay;
 
 
 
 
 
 
 
 395
 396	/* Timestamps: */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 397
 398	/* When did we last run on a CPU? */
 399	unsigned long long		last_arrival;
 
 
 
 
 
 
 
 
 
 400
 401	/* When were we last queued to run? */
 402	unsigned long long		last_queued;
 
 
 
 
 403
 404#endif /* CONFIG_SCHED_INFO */
 405};
 
 
 
 406
 407/*
 408 * Integer metrics need fixed point arithmetic, e.g., sched/fair
 409 * has a few: load, load_avg, util_avg, freq, and capacity.
 410 *
 411 * We define a basic fixed point arithmetic range, and then formalize
 412 * all these metrics based on that basic range.
 413 */
 414# define SCHED_FIXEDPOINT_SHIFT		10
 415# define SCHED_FIXEDPOINT_SCALE		(1L << SCHED_FIXEDPOINT_SHIFT)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 416
 417/* Increase resolution of cpu_capacity calculations */
 418# define SCHED_CAPACITY_SHIFT		SCHED_FIXEDPOINT_SHIFT
 419# define SCHED_CAPACITY_SCALE		(1L << SCHED_CAPACITY_SHIFT)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 420
 421struct load_weight {
 422	unsigned long			weight;
 423	u32				inv_weight;
 424};
 425
 426/*
 427 * The load/runnable/util_avg accumulates an infinite geometric series
 428 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
 429 *
 430 * [load_avg definition]
 431 *
 432 *   load_avg = runnable% * scale_load_down(load)
 433 *
 434 * [runnable_avg definition]
 435 *
 436 *   runnable_avg = runnable% * SCHED_CAPACITY_SCALE
 437 *
 438 * [util_avg definition]
 439 *
 440 *   util_avg = running% * SCHED_CAPACITY_SCALE
 441 *
 442 * where runnable% is the time ratio that a sched_entity is runnable and
 443 * running% the time ratio that a sched_entity is running.
 444 *
 445 * For cfs_rq, they are the aggregated values of all runnable and blocked
 446 * sched_entities.
 447 *
 448 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
 449 * capacity scaling. The scaling is done through the rq_clock_pelt that is used
 450 * for computing those signals (see update_rq_clock_pelt())
 451 *
 452 * N.B., the above ratios (runnable% and running%) themselves are in the
 453 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
 454 * to as large a range as necessary. This is for example reflected by
 455 * util_avg's SCHED_CAPACITY_SCALE.
 456 *
 457 * [Overflow issue]
 458 *
 459 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
 460 * with the highest load (=88761), always runnable on a single cfs_rq,
 461 * and should not overflow as the number already hits PID_MAX_LIMIT.
 462 *
 463 * For all other cases (including 32-bit kernels), struct load_weight's
 464 * weight will overflow first before we do, because:
 465 *
 466 *    Max(load_avg) <= Max(load.weight)
 467 *
 468 * Then it is the load_weight's responsibility to consider overflow
 469 * issues.
 470 */
 471struct sched_avg {
 472	u64				last_update_time;
 473	u64				load_sum;
 474	u64				runnable_sum;
 475	u32				util_sum;
 476	u32				period_contrib;
 477	unsigned long			load_avg;
 478	unsigned long			runnable_avg;
 479	unsigned long			util_avg;
 480	unsigned int			util_est;
 481} ____cacheline_aligned;
 482
 483/*
 484 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
 485 * updates. When a task is dequeued, its util_est should not be updated if its
 486 * util_avg has not been updated in the meantime.
 487 * This information is mapped into the MSB bit of util_est at dequeue time.
 488 * Since max value of util_est for a task is 1024 (PELT util_avg for a task)
 489 * it is safe to use MSB.
 490 */
 491#define UTIL_EST_WEIGHT_SHIFT		2
 492#define UTIL_AVG_UNCHANGED		0x80000000
 493
 
 494struct sched_statistics {
 495#ifdef CONFIG_SCHEDSTATS
 496	u64				wait_start;
 497	u64				wait_max;
 498	u64				wait_count;
 499	u64				wait_sum;
 500	u64				iowait_count;
 501	u64				iowait_sum;
 502
 503	u64				sleep_start;
 504	u64				sleep_max;
 505	s64				sum_sleep_runtime;
 506
 507	u64				block_start;
 508	u64				block_max;
 509	s64				sum_block_runtime;
 510
 511	s64				exec_max;
 512	u64				slice_max;
 513
 514	u64				nr_migrations_cold;
 515	u64				nr_failed_migrations_affine;
 516	u64				nr_failed_migrations_running;
 517	u64				nr_failed_migrations_hot;
 518	u64				nr_forced_migrations;
 519
 520	u64				nr_wakeups;
 521	u64				nr_wakeups_sync;
 522	u64				nr_wakeups_migrate;
 523	u64				nr_wakeups_local;
 524	u64				nr_wakeups_remote;
 525	u64				nr_wakeups_affine;
 526	u64				nr_wakeups_affine_attempts;
 527	u64				nr_wakeups_passive;
 528	u64				nr_wakeups_idle;
 529
 530#ifdef CONFIG_SCHED_CORE
 531	u64				core_forceidle_sum;
 532#endif
 533#endif /* CONFIG_SCHEDSTATS */
 534} ____cacheline_aligned;
 535
 536struct sched_entity {
 537	/* For load-balancing: */
 538	struct load_weight		load;
 539	struct rb_node			run_node;
 540	u64				deadline;
 541	u64				min_vruntime;
 542
 543	struct list_head		group_node;
 544	unsigned int			on_rq;
 545
 546	u64				exec_start;
 547	u64				sum_exec_runtime;
 548	u64				prev_sum_exec_runtime;
 549	u64				vruntime;
 550	s64				vlag;
 551	u64				slice;
 552
 553	u64				nr_migrations;
 
 
 554
 555#ifdef CONFIG_FAIR_GROUP_SCHED
 556	int				depth;
 557	struct sched_entity		*parent;
 558	/* rq on which this entity is (to be) queued: */
 559	struct cfs_rq			*cfs_rq;
 560	/* rq "owned" by this entity/group: */
 561	struct cfs_rq			*my_q;
 562	/* cached value of my_q->h_nr_running */
 563	unsigned long			runnable_weight;
 564#endif
 565
 566#ifdef CONFIG_SMP
 567	/*
 568	 * Per entity load average tracking.
 569	 *
 570	 * Put into separate cache line so it does not
 571	 * collide with read-mostly values above.
 572	 */
 573	struct sched_avg		avg;
 574#endif
 575};
 576
 577struct sched_rt_entity {
 578	struct list_head		run_list;
 579	unsigned long			timeout;
 580	unsigned long			watchdog_stamp;
 581	unsigned int			time_slice;
 582	unsigned short			on_rq;
 583	unsigned short			on_list;
 584
 585	struct sched_rt_entity		*back;
 586#ifdef CONFIG_RT_GROUP_SCHED
 587	struct sched_rt_entity		*parent;
 588	/* rq on which this entity is (to be) queued: */
 589	struct rt_rq			*rt_rq;
 590	/* rq "owned" by this entity/group: */
 591	struct rt_rq			*my_q;
 592#endif
 593} __randomize_layout;
 594
 595typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *);
 596typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *);
 597
 598struct sched_dl_entity {
 599	struct rb_node			rb_node;
 600
 601	/*
 602	 * Original scheduling parameters. Copied here from sched_attr
 603	 * during sched_setattr(), they will remain the same until
 604	 * the next sched_setattr().
 605	 */
 606	u64				dl_runtime;	/* Maximum runtime for each instance	*/
 607	u64				dl_deadline;	/* Relative deadline of each instance	*/
 608	u64				dl_period;	/* Separation of two instances (period) */
 609	u64				dl_bw;		/* dl_runtime / dl_period		*/
 610	u64				dl_density;	/* dl_runtime / dl_deadline		*/
 611
 612	/*
 613	 * Actual scheduling parameters. Initialized with the values above,
 614	 * they are continuously updated during task execution. Note that
 615	 * the remaining runtime could be < 0 in case we are in overrun.
 616	 */
 617	s64				runtime;	/* Remaining runtime for this instance	*/
 618	u64				deadline;	/* Absolute deadline for this instance	*/
 619	unsigned int			flags;		/* Specifying the scheduler behaviour	*/
 620
 621	/*
 622	 * Some bool flags:
 623	 *
 624	 * @dl_throttled tells if we exhausted the runtime. If so, the
 625	 * task has to wait for a replenishment to be performed at the
 626	 * next firing of dl_timer.
 627	 *
 628	 * @dl_yielded tells if task gave up the CPU before consuming
 629	 * all its available runtime during the last job.
 
 630	 *
 631	 * @dl_non_contending tells if the task is inactive while still
 632	 * contributing to the active utilization. In other words, it
 633	 * indicates if the inactive timer has been armed and its handler
 634	 * has not been executed yet. This flag is useful to avoid race
 635	 * conditions between the inactive timer handler and the wakeup
 636	 * code.
 637	 *
 638	 * @dl_overrun tells if the task asked to be informed about runtime
 639	 * overruns.
 640	 */
 641	unsigned int			dl_throttled      : 1;
 642	unsigned int			dl_yielded        : 1;
 643	unsigned int			dl_non_contending : 1;
 644	unsigned int			dl_overrun	  : 1;
 645	unsigned int			dl_server         : 1;
 646
 647	/*
 648	 * Bandwidth enforcement timer. Each -deadline task has its
 649	 * own bandwidth to be enforced, thus we need one timer per task.
 650	 */
 651	struct hrtimer			dl_timer;
 652
 653	/*
 654	 * Inactive timer, responsible for decreasing the active utilization
 655	 * at the "0-lag time". When a -deadline task blocks, it contributes
 656	 * to GRUB's active utilization until the "0-lag time", hence a
 657	 * timer is needed to decrease the active utilization at the correct
 658	 * time.
 659	 */
 660	struct hrtimer			inactive_timer;
 661
 662	/*
 663	 * Bits for DL-server functionality. Also see the comment near
 664	 * dl_server_update().
 665	 *
 666	 * @rq the runqueue this server is for
 667	 *
 668	 * @server_has_tasks() returns true if @server_pick return a
 669	 * runnable task.
 670	 */
 671	struct rq			*rq;
 672	dl_server_has_tasks_f		server_has_tasks;
 673	dl_server_pick_f		server_pick;
 674
 675#ifdef CONFIG_RT_MUTEXES
 676	/*
 677	 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
 678	 * pi_se points to the donor, otherwise points to the dl_se it belongs
 679	 * to (the original one/itself).
 680	 */
 681	struct sched_dl_entity *pi_se;
 682#endif
 683};
 684
 685#ifdef CONFIG_UCLAMP_TASK
 686/* Number of utilization clamp buckets (shorter alias) */
 687#define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
 688
 689/*
 690 * Utilization clamp for a scheduling entity
 691 * @value:		clamp value "assigned" to a se
 692 * @bucket_id:		bucket index corresponding to the "assigned" value
 693 * @active:		the se is currently refcounted in a rq's bucket
 694 * @user_defined:	the requested clamp value comes from user-space
 695 *
 696 * The bucket_id is the index of the clamp bucket matching the clamp value
 697 * which is pre-computed and stored to avoid expensive integer divisions from
 698 * the fast path.
 699 *
 700 * The active bit is set whenever a task has got an "effective" value assigned,
 701 * which can be different from the clamp value "requested" from user-space.
 702 * This allows to know a task is refcounted in the rq's bucket corresponding
 703 * to the "effective" bucket_id.
 704 *
 705 * The user_defined bit is set whenever a task has got a task-specific clamp
 706 * value requested from userspace, i.e. the system defaults apply to this task
 707 * just as a restriction. This allows to relax default clamps when a less
 708 * restrictive task-specific value has been requested, thus allowing to
 709 * implement a "nice" semantic. For example, a task running with a 20%
 710 * default boost can still drop its own boosting to 0%.
 711 */
 712struct uclamp_se {
 713	unsigned int value		: bits_per(SCHED_CAPACITY_SCALE);
 714	unsigned int bucket_id		: bits_per(UCLAMP_BUCKETS);
 715	unsigned int active		: 1;
 716	unsigned int user_defined	: 1;
 717};
 718#endif /* CONFIG_UCLAMP_TASK */
 719
 720union rcu_special {
 721	struct {
 722		u8			blocked;
 723		u8			need_qs;
 724		u8			exp_hint; /* Hint for performance. */
 725		u8			need_mb; /* Readers need smp_mb(). */
 726	} b; /* Bits. */
 727	u32 s; /* Set of bits. */
 728};
 729
 730enum perf_event_task_context {
 731	perf_invalid_context = -1,
 732	perf_hw_context = 0,
 733	perf_sw_context,
 734	perf_nr_task_contexts,
 735};
 736
 737struct wake_q_node {
 738	struct wake_q_node *next;
 739};
 740
 741struct kmap_ctrl {
 742#ifdef CONFIG_KMAP_LOCAL
 743	int				idx;
 744	pte_t				pteval[KM_MAX_IDX];
 745#endif
 746};
 747
 748struct task_struct {
 749#ifdef CONFIG_THREAD_INFO_IN_TASK
 750	/*
 751	 * For reasons of header soup (see current_thread_info()), this
 752	 * must be the first element of task_struct.
 753	 */
 754	struct thread_info		thread_info;
 755#endif
 756	unsigned int			__state;
 757
 758	/* saved state for "spinlock sleepers" */
 759	unsigned int			saved_state;
 760
 761	/*
 762	 * This begins the randomizable portion of task_struct. Only
 763	 * scheduling-critical items should be added above here.
 764	 */
 765	randomized_struct_fields_start
 766
 767	void				*stack;
 768	refcount_t			usage;
 769	/* Per task flags (PF_*), defined further below: */
 770	unsigned int			flags;
 771	unsigned int			ptrace;
 772
 773#ifdef CONFIG_SMP
 774	int				on_cpu;
 775	struct __call_single_node	wake_entry;
 776	unsigned int			wakee_flips;
 777	unsigned long			wakee_flip_decay_ts;
 778	struct task_struct		*last_wakee;
 779
 780	/*
 781	 * recent_used_cpu is initially set as the last CPU used by a task
 782	 * that wakes affine another task. Waker/wakee relationships can
 783	 * push tasks around a CPU where each wakeup moves to the next one.
 784	 * Tracking a recently used CPU allows a quick search for a recently
 785	 * used CPU that may be idle.
 786	 */
 787	int				recent_used_cpu;
 788	int				wake_cpu;
 789#endif
 790	int				on_rq;
 791
 792	int				prio;
 793	int				static_prio;
 794	int				normal_prio;
 795	unsigned int			rt_priority;
 796
 797	struct sched_entity		se;
 798	struct sched_rt_entity		rt;
 799	struct sched_dl_entity		dl;
 800	struct sched_dl_entity		*dl_server;
 801	const struct sched_class	*sched_class;
 802
 803#ifdef CONFIG_SCHED_CORE
 804	struct rb_node			core_node;
 805	unsigned long			core_cookie;
 806	unsigned int			core_occupation;
 807#endif
 808
 809#ifdef CONFIG_CGROUP_SCHED
 810	struct task_group		*sched_task_group;
 811#endif
 812
 813#ifdef CONFIG_UCLAMP_TASK
 814	/*
 815	 * Clamp values requested for a scheduling entity.
 816	 * Must be updated with task_rq_lock() held.
 817	 */
 818	struct uclamp_se		uclamp_req[UCLAMP_CNT];
 819	/*
 820	 * Effective clamp values used for a scheduling entity.
 821	 * Must be updated with task_rq_lock() held.
 822	 */
 823	struct uclamp_se		uclamp[UCLAMP_CNT];
 824#endif
 825
 826	struct sched_statistics         stats;
 827
 828#ifdef CONFIG_PREEMPT_NOTIFIERS
 829	/* List of struct preempt_notifier: */
 830	struct hlist_head		preempt_notifiers;
 831#endif
 832
 833#ifdef CONFIG_BLK_DEV_IO_TRACE
 834	unsigned int			btrace_seq;
 835#endif
 836
 837	unsigned int			policy;
 838	int				nr_cpus_allowed;
 839	const cpumask_t			*cpus_ptr;
 840	cpumask_t			*user_cpus_ptr;
 841	cpumask_t			cpus_mask;
 842	void				*migration_pending;
 843#ifdef CONFIG_SMP
 844	unsigned short			migration_disabled;
 845#endif
 846	unsigned short			migration_flags;
 847
 848#ifdef CONFIG_PREEMPT_RCU
 849	int				rcu_read_lock_nesting;
 850	union rcu_special		rcu_read_unlock_special;
 851	struct list_head		rcu_node_entry;
 852	struct rcu_node			*rcu_blocked_node;
 853#endif /* #ifdef CONFIG_PREEMPT_RCU */
 
 
 
 
 
 
 854
 855#ifdef CONFIG_TASKS_RCU
 856	unsigned long			rcu_tasks_nvcsw;
 857	u8				rcu_tasks_holdout;
 858	u8				rcu_tasks_idx;
 859	int				rcu_tasks_idle_cpu;
 860	struct list_head		rcu_tasks_holdout_list;
 861#endif /* #ifdef CONFIG_TASKS_RCU */
 862
 863#ifdef CONFIG_TASKS_TRACE_RCU
 864	int				trc_reader_nesting;
 865	int				trc_ipi_to_cpu;
 866	union rcu_special		trc_reader_special;
 867	struct list_head		trc_holdout_list;
 868	struct list_head		trc_blkd_node;
 869	int				trc_blkd_cpu;
 870#endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
 871
 872	struct sched_info		sched_info;
 873
 874	struct list_head		tasks;
 875#ifdef CONFIG_SMP
 876	struct plist_node		pushable_tasks;
 877	struct rb_node			pushable_dl_tasks;
 878#endif
 879
 880	struct mm_struct		*mm;
 881	struct mm_struct		*active_mm;
 882	struct address_space		*faults_disabled_mapping;
 883
 884	int				exit_state;
 885	int				exit_code;
 886	int				exit_signal;
 887	/* The signal sent when the parent dies: */
 888	int				pdeath_signal;
 889	/* JOBCTL_*, siglock protected: */
 890	unsigned long			jobctl;
 891
 892	/* Used for emulating ABI behavior of previous Linux versions: */
 893	unsigned int			personality;
 894
 895	/* Scheduler bits, serialized by scheduler locks: */
 896	unsigned			sched_reset_on_fork:1;
 897	unsigned			sched_contributes_to_load:1;
 898	unsigned			sched_migrated:1;
 899
 900	/* Force alignment to the next boundary: */
 901	unsigned			:0;
 902
 903	/* Unserialized, strictly 'current' */
 904
 905	/*
 906	 * This field must not be in the scheduler word above due to wakelist
 907	 * queueing no longer being serialized by p->on_cpu. However:
 908	 *
 909	 * p->XXX = X;			ttwu()
 910	 * schedule()			  if (p->on_rq && ..) // false
 911	 *   smp_mb__after_spinlock();	  if (smp_load_acquire(&p->on_cpu) && //true
 912	 *   deactivate_task()		      ttwu_queue_wakelist())
 913	 *     p->on_rq = 0;			p->sched_remote_wakeup = Y;
 914	 *
 915	 * guarantees all stores of 'current' are visible before
 916	 * ->sched_remote_wakeup gets used, so it can be in this word.
 917	 */
 918	unsigned			sched_remote_wakeup:1;
 919#ifdef CONFIG_RT_MUTEXES
 920	unsigned			sched_rt_mutex:1;
 921#endif
 922
 923	/* Bit to tell TOMOYO we're in execve(): */
 924	unsigned			in_execve:1;
 925	unsigned			in_iowait:1;
 926#ifndef TIF_RESTORE_SIGMASK
 927	unsigned			restore_sigmask:1;
 928#endif
 929#ifdef CONFIG_MEMCG
 930	unsigned			in_user_fault:1;
 931#endif
 932#ifdef CONFIG_LRU_GEN
 933	/* whether the LRU algorithm may apply to this access */
 934	unsigned			in_lru_fault:1;
 935#endif
 936#ifdef CONFIG_COMPAT_BRK
 937	unsigned			brk_randomized:1;
 938#endif
 939#ifdef CONFIG_CGROUPS
 940	/* disallow userland-initiated cgroup migration */
 941	unsigned			no_cgroup_migration:1;
 942	/* task is frozen/stopped (used by the cgroup freezer) */
 943	unsigned			frozen:1;
 944#endif
 945#ifdef CONFIG_BLK_CGROUP
 946	unsigned			use_memdelay:1;
 947#endif
 948#ifdef CONFIG_PSI
 949	/* Stalled due to lack of memory */
 950	unsigned			in_memstall:1;
 951#endif
 952#ifdef CONFIG_PAGE_OWNER
 953	/* Used by page_owner=on to detect recursion in page tracking. */
 954	unsigned			in_page_owner:1;
 955#endif
 956#ifdef CONFIG_EVENTFD
 957	/* Recursion prevention for eventfd_signal() */
 958	unsigned			in_eventfd:1;
 959#endif
 960#ifdef CONFIG_ARCH_HAS_CPU_PASID
 961	unsigned			pasid_activated:1;
 962#endif
 963#ifdef	CONFIG_CPU_SUP_INTEL
 964	unsigned			reported_split_lock:1;
 965#endif
 966#ifdef CONFIG_TASK_DELAY_ACCT
 967	/* delay due to memory thrashing */
 968	unsigned                        in_thrashing:1;
 969#endif
 
 
 
 
 
 
 
 
 
 
 
 
 970
 971	unsigned long			atomic_flags; /* Flags requiring atomic access. */
 
 972
 973	struct restart_block		restart_block;
 
 
 974
 975	pid_t				pid;
 976	pid_t				tgid;
 977
 978#ifdef CONFIG_STACKPROTECTOR
 979	/* Canary value for the -fstack-protector GCC feature: */
 980	unsigned long			stack_canary;
 981#endif
 982	/*
 983	 * Pointers to the (original) parent process, youngest child, younger sibling,
 984	 * older sibling, respectively.  (p->father can be replaced with
 985	 * p->real_parent->pid)
 986	 */
 987
 988	/* Real parent process: */
 989	struct task_struct __rcu	*real_parent;
 990
 991	/* Recipient of SIGCHLD, wait4() reports: */
 992	struct task_struct __rcu	*parent;
 993
 994	/*
 995	 * Children/sibling form the list of natural children:
 996	 */
 997	struct list_head		children;
 998	struct list_head		sibling;
 999	struct task_struct		*group_leader;
1000
1001	/*
1002	 * 'ptraced' is the list of tasks this task is using ptrace() on.
1003	 *
1004	 * This includes both natural children and PTRACE_ATTACH targets.
1005	 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
1006	 */
1007	struct list_head		ptraced;
1008	struct list_head		ptrace_entry;
1009
1010	/* PID/PID hash table linkage. */
1011	struct pid			*thread_pid;
1012	struct hlist_node		pid_links[PIDTYPE_MAX];
1013	struct list_head		thread_node;
 
 
 
 
1014
1015	struct completion		*vfork_done;
1016
1017	/* CLONE_CHILD_SETTID: */
1018	int __user			*set_child_tid;
1019
1020	/* CLONE_CHILD_CLEARTID: */
1021	int __user			*clear_child_tid;
1022
1023	/* PF_KTHREAD | PF_IO_WORKER */
1024	void				*worker_private;
1025
1026	u64				utime;
1027	u64				stime;
1028#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1029	u64				utimescaled;
1030	u64				stimescaled;
1031#endif
1032	u64				gtime;
1033	struct prev_cputime		prev_cputime;
1034#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1035	struct vtime			vtime;
1036#endif
1037
1038#ifdef CONFIG_NO_HZ_FULL
1039	atomic_t			tick_dep_mask;
1040#endif
1041	/* Context switch counts: */
1042	unsigned long			nvcsw;
1043	unsigned long			nivcsw;
1044
1045	/* Monotonic time in nsecs: */
1046	u64				start_time;
1047
1048	/* Boot based time in nsecs: */
1049	u64				start_boottime;
1050
1051	/* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1052	unsigned long			min_flt;
1053	unsigned long			maj_flt;
1054
1055	/* Empty if CONFIG_POSIX_CPUTIMERS=n */
1056	struct posix_cputimers		posix_cputimers;
1057
1058#ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1059	struct posix_cputimers_work	posix_cputimers_work;
1060#endif
1061
1062	/* Process credentials: */
1063
1064	/* Tracer's credentials at attach: */
1065	const struct cred __rcu		*ptracer_cred;
1066
1067	/* Objective and real subjective task credentials (COW): */
1068	const struct cred __rcu		*real_cred;
1069
1070	/* Effective (overridable) subjective task credentials (COW): */
1071	const struct cred __rcu		*cred;
1072
1073#ifdef CONFIG_KEYS
1074	/* Cached requested key. */
1075	struct key			*cached_requested_key;
1076#endif
1077
1078	/*
1079	 * executable name, excluding path.
1080	 *
1081	 * - normally initialized setup_new_exec()
1082	 * - access it with [gs]et_task_comm()
1083	 * - lock it with task_lock()
1084	 */
1085	char				comm[TASK_COMM_LEN];
1086
1087	struct nameidata		*nameidata;
1088
1089#ifdef CONFIG_SYSVIPC
1090	struct sysv_sem			sysvsem;
1091	struct sysv_shm			sysvshm;
1092#endif
1093#ifdef CONFIG_DETECT_HUNG_TASK
1094	unsigned long			last_switch_count;
1095	unsigned long			last_switch_time;
1096#endif
1097	/* Filesystem information: */
1098	struct fs_struct		*fs;
1099
1100	/* Open file information: */
1101	struct files_struct		*files;
1102
1103#ifdef CONFIG_IO_URING
1104	struct io_uring_task		*io_uring;
1105#endif
1106
1107	/* Namespaces: */
1108	struct nsproxy			*nsproxy;
1109
1110	/* Signal handlers: */
1111	struct signal_struct		*signal;
1112	struct sighand_struct __rcu		*sighand;
1113	sigset_t			blocked;
1114	sigset_t			real_blocked;
1115	/* Restored if set_restore_sigmask() was used: */
1116	sigset_t			saved_sigmask;
1117	struct sigpending		pending;
1118	unsigned long			sas_ss_sp;
1119	size_t				sas_ss_size;
1120	unsigned int			sas_ss_flags;
1121
1122	struct callback_head		*task_works;
1123
1124#ifdef CONFIG_AUDIT
1125#ifdef CONFIG_AUDITSYSCALL
1126	struct audit_context		*audit_context;
 
1127#endif
1128	kuid_t				loginuid;
1129	unsigned int			sessionid;
1130#endif
1131	struct seccomp			seccomp;
1132	struct syscall_user_dispatch	syscall_dispatch;
1133
1134	/* Thread group tracking: */
1135	u64				parent_exec_id;
1136	u64				self_exec_id;
1137
1138	/* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1139	spinlock_t			alloc_lock;
 
 
 
 
1140
1141	/* Protection of the PI data structures: */
1142	raw_spinlock_t			pi_lock;
1143
1144	struct wake_q_node		wake_q;
1145
1146#ifdef CONFIG_RT_MUTEXES
1147	/* PI waiters blocked on a rt_mutex held by this task: */
1148	struct rb_root_cached		pi_waiters;
1149	/* Updated under owner's pi_lock and rq lock */
1150	struct task_struct		*pi_top_task;
1151	/* Deadlock detection and priority inheritance handling: */
1152	struct rt_mutex_waiter		*pi_blocked_on;
 
1153#endif
1154
1155#ifdef CONFIG_DEBUG_MUTEXES
1156	/* Mutex deadlock detection: */
1157	struct mutex_waiter		*blocked_on;
1158#endif
1159
1160#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1161	int				non_block_count;
1162#endif
1163
1164#ifdef CONFIG_TRACE_IRQFLAGS
1165	struct irqtrace_events		irqtrace;
1166	unsigned int			hardirq_threaded;
1167	u64				hardirq_chain_key;
1168	int				softirqs_enabled;
1169	int				softirq_context;
1170	int				irq_config;
 
 
 
 
 
 
 
1171#endif
1172#ifdef CONFIG_PREEMPT_RT
1173	int				softirq_disable_cnt;
1174#endif
1175
1176#ifdef CONFIG_LOCKDEP
1177# define MAX_LOCK_DEPTH			48UL
1178	u64				curr_chain_key;
1179	int				lockdep_depth;
1180	unsigned int			lockdep_recursion;
1181	struct held_lock		held_locks[MAX_LOCK_DEPTH];
1182#endif
1183
1184#if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1185	unsigned int			in_ubsan;
1186#endif
1187
1188	/* Journalling filesystem info: */
1189	void				*journal_info;
1190
1191	/* Stacked block device info: */
1192	struct bio_list			*bio_list;
1193
1194	/* Stack plugging: */
1195	struct blk_plug			*plug;
 
 
1196
1197	/* VM state: */
1198	struct reclaim_state		*reclaim_state;
1199
1200	struct io_context		*io_context;
1201
1202#ifdef CONFIG_COMPACTION
1203	struct capture_control		*capture_control;
1204#endif
1205	/* Ptrace state: */
1206	unsigned long			ptrace_message;
1207	kernel_siginfo_t		*last_siginfo;
1208
1209	struct task_io_accounting	ioac;
1210#ifdef CONFIG_PSI
1211	/* Pressure stall state */
1212	unsigned int			psi_flags;
1213#endif
1214#ifdef CONFIG_TASK_XACCT
1215	/* Accumulated RSS usage: */
1216	u64				acct_rss_mem1;
1217	/* Accumulated virtual memory usage: */
1218	u64				acct_vm_mem1;
1219	/* stime + utime since last update: */
1220	u64				acct_timexpd;
1221#endif
1222#ifdef CONFIG_CPUSETS
1223	/* Protected by ->alloc_lock: */
1224	nodemask_t			mems_allowed;
1225	/* Sequence number to catch updates: */
1226	seqcount_spinlock_t		mems_allowed_seq;
1227	int				cpuset_mem_spread_rotor;
1228	int				cpuset_slab_spread_rotor;
1229#endif
1230#ifdef CONFIG_CGROUPS
1231	/* Control Group info protected by css_set_lock: */
1232	struct css_set __rcu		*cgroups;
1233	/* cg_list protected by css_set_lock and tsk->alloc_lock: */
1234	struct list_head		cg_list;
1235#endif
1236#ifdef CONFIG_X86_CPU_RESCTRL
1237	u32				closid;
1238	u32				rmid;
1239#endif
1240#ifdef CONFIG_FUTEX
1241	struct robust_list_head __user	*robust_list;
1242#ifdef CONFIG_COMPAT
1243	struct compat_robust_list_head __user *compat_robust_list;
1244#endif
1245	struct list_head		pi_state_list;
1246	struct futex_pi_state		*pi_state_cache;
1247	struct mutex			futex_exit_mutex;
1248	unsigned int			futex_state;
1249#endif
1250#ifdef CONFIG_PERF_EVENTS
1251	struct perf_event_context	*perf_event_ctxp;
1252	struct mutex			perf_event_mutex;
1253	struct list_head		perf_event_list;
1254#endif
1255#ifdef CONFIG_DEBUG_PREEMPT
1256	unsigned long			preempt_disable_ip;
1257#endif
1258#ifdef CONFIG_NUMA
1259	/* Protected by alloc_lock: */
1260	struct mempolicy		*mempolicy;
1261	short				il_prev;
1262	short				pref_node_fork;
1263#endif
1264#ifdef CONFIG_NUMA_BALANCING
1265	int				numa_scan_seq;
1266	unsigned int			numa_scan_period;
1267	unsigned int			numa_scan_period_max;
1268	int				numa_preferred_nid;
1269	unsigned long			numa_migrate_retry;
1270	/* Migration stamp: */
1271	u64				node_stamp;
1272	u64				last_task_numa_placement;
1273	u64				last_sum_exec_runtime;
1274	struct callback_head		numa_work;
1275
1276	/*
1277	 * This pointer is only modified for current in syscall and
1278	 * pagefault context (and for tasks being destroyed), so it can be read
1279	 * from any of the following contexts:
1280	 *  - RCU read-side critical section
1281	 *  - current->numa_group from everywhere
1282	 *  - task's runqueue locked, task not running
1283	 */
1284	struct numa_group __rcu		*numa_group;
1285
1286	/*
1287	 * numa_faults is an array split into four regions:
1288	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1289	 * in this precise order.
1290	 *
1291	 * faults_memory: Exponential decaying average of faults on a per-node
1292	 * basis. Scheduling placement decisions are made based on these
1293	 * counts. The values remain static for the duration of a PTE scan.
1294	 * faults_cpu: Track the nodes the process was running on when a NUMA
1295	 * hinting fault was incurred.
1296	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1297	 * during the current scan window. When the scan completes, the counts
1298	 * in faults_memory and faults_cpu decay and these values are copied.
1299	 */
1300	unsigned long			*numa_faults;
1301	unsigned long			total_numa_faults;
1302
1303	/*
1304	 * numa_faults_locality tracks if faults recorded during the last
1305	 * scan window were remote/local or failed to migrate. The task scan
1306	 * period is adapted based on the locality of the faults with different
1307	 * weights depending on whether they were shared or private faults
1308	 */
1309	unsigned long			numa_faults_locality[3];
1310
1311	unsigned long			numa_pages_migrated;
1312#endif /* CONFIG_NUMA_BALANCING */
 
 
 
 
1313
1314#ifdef CONFIG_RSEQ
1315	struct rseq __user *rseq;
1316	u32 rseq_len;
1317	u32 rseq_sig;
1318	/*
1319	 * RmW on rseq_event_mask must be performed atomically
1320	 * with respect to preemption.
 
 
1321	 */
1322	unsigned long rseq_event_mask;
1323#endif
1324
1325#ifdef CONFIG_SCHED_MM_CID
1326	int				mm_cid;		/* Current cid in mm */
1327	int				last_mm_cid;	/* Most recent cid in mm */
1328	int				migrate_from_cpu;
1329	int				mm_cid_active;	/* Whether cid bitmap is active */
1330	struct callback_head		cid_work;
1331#endif
1332
1333	struct tlbflush_unmap_batch	tlb_ubc;
1334
1335	/* Cache last used pipe for splice(): */
1336	struct pipe_inode_info		*splice_pipe;
 
 
1337
1338	struct page_frag		task_frag;
1339
1340#ifdef CONFIG_TASK_DELAY_ACCT
1341	struct task_delay_info		*delays;
1342#endif
1343
1344#ifdef CONFIG_FAULT_INJECTION
1345	int				make_it_fail;
1346	unsigned int			fail_nth;
1347#endif
1348	/*
1349	 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1350	 * balance_dirty_pages() for a dirty throttling pause:
1351	 */
1352	int				nr_dirtied;
1353	int				nr_dirtied_pause;
1354	/* Start of a write-and-pause period: */
1355	unsigned long			dirty_paused_when;
1356
1357#ifdef CONFIG_LATENCYTOP
1358	int				latency_record_count;
1359	struct latency_record		latency_record[LT_SAVECOUNT];
1360#endif
1361	/*
1362	 * Time slack values; these are used to round up poll() and
1363	 * select() etc timeout values. These are in nanoseconds.
1364	 */
1365	u64				timer_slack_ns;
1366	u64				default_timer_slack_ns;
1367
1368#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1369	unsigned int			kasan_depth;
 
 
 
 
 
 
 
 
 
 
 
 
1370#endif
1371
1372#ifdef CONFIG_KCSAN
1373	struct kcsan_ctx		kcsan_ctx;
1374#ifdef CONFIG_TRACE_IRQFLAGS
1375	struct irqtrace_events		kcsan_save_irqtrace;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1376#endif
1377#ifdef CONFIG_KCSAN_WEAK_MEMORY
1378	int				kcsan_stack_depth;
1379#endif
 
 
 
1380#endif
 
1381
1382#ifdef CONFIG_KMSAN
1383	struct kmsan_ctx		kmsan_ctx;
1384#endif
1385
1386#if IS_ENABLED(CONFIG_KUNIT)
1387	struct kunit			*kunit_test;
1388#endif
 
1389
1390#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1391	/* Index of current stored address in ret_stack: */
1392	int				curr_ret_stack;
1393	int				curr_ret_depth;
1394
1395	/* Stack of return addresses for return function tracing: */
1396	struct ftrace_ret_stack		*ret_stack;
1397
1398	/* Timestamp for last schedule: */
1399	unsigned long long		ftrace_timestamp;
1400
1401	/*
1402	 * Number of functions that haven't been traced
1403	 * because of depth overrun:
1404	 */
1405	atomic_t			trace_overrun;
1406
1407	/* Pause tracing: */
1408	atomic_t			tracing_graph_pause;
 
 
 
 
 
 
 
 
1409#endif
1410
1411#ifdef CONFIG_TRACING
1412	/* Bitmask and counter of trace recursion: */
1413	unsigned long			trace_recursion;
1414#endif /* CONFIG_TRACING */
1415
1416#ifdef CONFIG_KCOV
1417	/* See kernel/kcov.c for more details. */
 
 
1418
1419	/* Coverage collection mode enabled for this task (0 if disabled): */
1420	unsigned int			kcov_mode;
 
 
 
 
 
 
 
1421
1422	/* Size of the kcov_area: */
1423	unsigned int			kcov_size;
 
 
1424
1425	/* Buffer for coverage collection: */
1426	void				*kcov_area;
1427
1428	/* KCOV descriptor wired with this task or NULL: */
1429	struct kcov			*kcov;
 
 
 
 
 
 
 
 
 
 
 
 
 
1430
1431	/* KCOV common handle for remote coverage collection: */
1432	u64				kcov_handle;
 
 
1433
1434	/* KCOV sequence number: */
1435	int				kcov_sequence;
 
 
 
1436
1437	/* Collect coverage from softirq context: */
1438	unsigned int			kcov_softirq;
1439#endif
 
1440
1441#ifdef CONFIG_MEMCG
1442	struct mem_cgroup		*memcg_in_oom;
1443	gfp_t				memcg_oom_gfp_mask;
1444	int				memcg_oom_order;
1445
1446	/* Number of pages to reclaim on returning to userland: */
1447	unsigned int			memcg_nr_pages_over_high;
 
 
1448
1449	/* Used by memcontrol for targeted memcg charge: */
1450	struct mem_cgroup		*active_memcg;
1451#endif
1452
1453#ifdef CONFIG_MEMCG_KMEM
1454	struct obj_cgroup		*objcg;
1455#endif
 
1456
1457#ifdef CONFIG_BLK_CGROUP
1458	struct gendisk			*throttle_disk;
1459#endif
1460
1461#ifdef CONFIG_UPROBES
1462	struct uprobe_task		*utask;
1463#endif
1464#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1465	unsigned int			sequential_io;
1466	unsigned int			sequential_io_avg;
1467#endif
1468	struct kmap_ctrl		kmap_ctrl;
1469#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1470	unsigned long			task_state_change;
1471# ifdef CONFIG_PREEMPT_RT
1472	unsigned long			saved_state_change;
1473# endif
1474#endif
1475	struct rcu_head			rcu;
1476	refcount_t			rcu_users;
1477	int				pagefault_disabled;
1478#ifdef CONFIG_MMU
1479	struct task_struct		*oom_reaper_list;
1480	struct timer_list		oom_reaper_timer;
1481#endif
1482#ifdef CONFIG_VMAP_STACK
1483	struct vm_struct		*stack_vm_area;
1484#endif
1485#ifdef CONFIG_THREAD_INFO_IN_TASK
1486	/* A live task holds one reference: */
1487	refcount_t			stack_refcount;
1488#endif
1489#ifdef CONFIG_LIVEPATCH
1490	int patch_state;
1491#endif
1492#ifdef CONFIG_SECURITY
1493	/* Used by LSM modules for access restriction: */
1494	void				*security;
1495#endif
1496#ifdef CONFIG_BPF_SYSCALL
1497	/* Used by BPF task local storage */
1498	struct bpf_local_storage __rcu	*bpf_storage;
1499	/* Used for BPF run context */
1500	struct bpf_run_ctx		*bpf_ctx;
1501#endif
1502
1503#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1504	unsigned long			lowest_stack;
1505	unsigned long			prev_lowest_stack;
1506#endif
1507
1508#ifdef CONFIG_X86_MCE
1509	void __user			*mce_vaddr;
1510	__u64				mce_kflags;
1511	u64				mce_addr;
1512	__u64				mce_ripv : 1,
1513					mce_whole_page : 1,
1514					__mce_reserved : 62;
1515	struct callback_head		mce_kill_me;
1516	int				mce_count;
1517#endif
1518
1519#ifdef CONFIG_KRETPROBES
1520	struct llist_head               kretprobe_instances;
1521#endif
1522#ifdef CONFIG_RETHOOK
1523	struct llist_head               rethooks;
1524#endif
1525
1526#ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1527	/*
1528	 * If L1D flush is supported on mm context switch
1529	 * then we use this callback head to queue kill work
1530	 * to kill tasks that are not running on SMT disabled
1531	 * cores
1532	 */
1533	struct callback_head		l1d_flush_kill;
1534#endif
1535
1536#ifdef CONFIG_RV
1537	/*
1538	 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS.
1539	 * If we find justification for more monitors, we can think
1540	 * about adding more or developing a dynamic method. So far,
1541	 * none of these are justified.
1542	 */
1543	union rv_task_monitor		rv[RV_PER_TASK_MONITORS];
1544#endif
1545
1546#ifdef CONFIG_USER_EVENTS
1547	struct user_event_mm		*user_event_mm;
1548#endif
1549
1550	/*
1551	 * New fields for task_struct should be added above here, so that
1552	 * they are included in the randomized portion of task_struct.
1553	 */
1554	randomized_struct_fields_end
1555
1556	/* CPU-specific state of this task: */
1557	struct thread_struct		thread;
 
 
1558
1559	/*
1560	 * WARNING: on x86, 'thread_struct' contains a variable-sized
1561	 * structure.  It *MUST* be at the end of 'task_struct'.
1562	 *
1563	 * Do not put anything below here!
1564	 */
1565};
1566
1567#define TASK_REPORT_IDLE	(TASK_REPORT + 1)
1568#define TASK_REPORT_MAX		(TASK_REPORT_IDLE << 1)
 
 
 
 
 
 
 
 
 
 
 
 
1569
1570static inline unsigned int __task_state_index(unsigned int tsk_state,
1571					      unsigned int tsk_exit_state)
 
 
 
 
 
 
 
1572{
1573	unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT;
 
1574
1575	BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1576
1577	if ((tsk_state & TASK_IDLE) == TASK_IDLE)
1578		state = TASK_REPORT_IDLE;
1579
1580	/*
1581	 * We're lying here, but rather than expose a completely new task state
1582	 * to userspace, we can make this appear as if the task has gone through
1583	 * a regular rt_mutex_lock() call.
1584	 */
1585	if (tsk_state & TASK_RTLOCK_WAIT)
1586		state = TASK_UNINTERRUPTIBLE;
1587
1588	return fls(state);
 
 
 
1589}
1590
1591static inline unsigned int task_state_index(struct task_struct *tsk)
 
 
 
 
 
 
 
 
1592{
1593	return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state);
 
 
 
1594}
1595
1596static inline char task_index_to_char(unsigned int state)
 
 
1597{
1598	static const char state_char[] = "RSDTtXZPI";
1599
1600	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1601
1602	return state_char[state];
1603}
1604
1605static inline char task_state_to_char(struct task_struct *tsk)
1606{
1607	return task_index_to_char(task_state_index(tsk));
1608}
1609
1610extern struct pid *cad_pid;
 
1611
1612/*
1613 * Per process flags
1614 */
1615#define PF_VCPU			0x00000001	/* I'm a virtual CPU */
1616#define PF_IDLE			0x00000002	/* I am an IDLE thread */
1617#define PF_EXITING		0x00000004	/* Getting shut down */
1618#define PF_POSTCOREDUMP		0x00000008	/* Coredumps should ignore this task */
1619#define PF_IO_WORKER		0x00000010	/* Task is an IO worker */
1620#define PF_WQ_WORKER		0x00000020	/* I'm a workqueue worker */
1621#define PF_FORKNOEXEC		0x00000040	/* Forked but didn't exec */
1622#define PF_MCE_PROCESS		0x00000080      /* Process policy on mce errors */
1623#define PF_SUPERPRIV		0x00000100	/* Used super-user privileges */
1624#define PF_DUMPCORE		0x00000200	/* Dumped core */
1625#define PF_SIGNALED		0x00000400	/* Killed by a signal */
1626#define PF_MEMALLOC		0x00000800	/* Allocating memory */
1627#define PF_NPROC_EXCEEDED	0x00001000	/* set_user() noticed that RLIMIT_NPROC was exceeded */
1628#define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
1629#define PF_USER_WORKER		0x00004000	/* Kernel thread cloned from userspace thread */
1630#define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
1631#define PF__HOLE__00010000	0x00010000
1632#define PF_KSWAPD		0x00020000	/* I am kswapd */
1633#define PF_MEMALLOC_NOFS	0x00040000	/* All allocation requests will inherit GFP_NOFS */
1634#define PF_MEMALLOC_NOIO	0x00080000	/* All allocation requests will inherit GFP_NOIO */
1635#define PF_LOCAL_THROTTLE	0x00100000	/* Throttle writes only against the bdi I write to,
1636						 * I am cleaning dirty pages from some other bdi. */
1637#define PF_KTHREAD		0x00200000	/* I am a kernel thread */
1638#define PF_RANDOMIZE		0x00400000	/* Randomize virtual address space */
1639#define PF__HOLE__00800000	0x00800000
1640#define PF__HOLE__01000000	0x01000000
1641#define PF__HOLE__02000000	0x02000000
1642#define PF_NO_SETAFFINITY	0x04000000	/* Userland is not allowed to meddle with cpus_mask */
1643#define PF_MCE_EARLY		0x08000000      /* Early kill for mce process policy */
1644#define PF_MEMALLOC_PIN		0x10000000	/* Allocation context constrained to zones which allow long term pinning. */
1645#define PF__HOLE__20000000	0x20000000
1646#define PF__HOLE__40000000	0x40000000
1647#define PF_SUSPEND_TASK		0x80000000      /* This thread called freeze_processes() and should not be frozen */
1648
1649/*
1650 * Only the _current_ task can read/write to tsk->flags, but other
1651 * tasks can access tsk->flags in readonly mode for example
1652 * with tsk_used_math (like during threaded core dumping).
1653 * There is however an exception to this rule during ptrace
1654 * or during fork: the ptracer task is allowed to write to the
1655 * child->flags of its traced child (same goes for fork, the parent
1656 * can write to the child->flags), because we're guaranteed the
1657 * child is not running and in turn not changing child->flags
1658 * at the same time the parent does it.
1659 */
1660#define clear_stopped_child_used_math(child)	do { (child)->flags &= ~PF_USED_MATH; } while (0)
1661#define set_stopped_child_used_math(child)	do { (child)->flags |= PF_USED_MATH; } while (0)
1662#define clear_used_math()			clear_stopped_child_used_math(current)
1663#define set_used_math()				set_stopped_child_used_math(current)
1664
1665#define conditional_stopped_child_used_math(condition, child) \
1666	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1667
1668#define conditional_used_math(condition)	conditional_stopped_child_used_math(condition, current)
 
1669
1670#define copy_to_stopped_child_used_math(child) \
1671	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
 
 
 
 
 
1672
1673/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1674#define tsk_used_math(p)			((p)->flags & PF_USED_MATH)
1675#define used_math()				tsk_used_math(current)
1676
1677static __always_inline bool is_percpu_thread(void)
1678{
1679#ifdef CONFIG_SMP
1680	return (current->flags & PF_NO_SETAFFINITY) &&
1681		(current->nr_cpus_allowed  == 1);
 
 
 
 
 
 
 
 
1682#else
1683	return true;
1684#endif
 
1685}
1686
1687/* Per-process atomic flags. */
1688#define PFA_NO_NEW_PRIVS		0	/* May not gain new privileges. */
1689#define PFA_SPREAD_PAGE			1	/* Spread page cache over cpuset */
1690#define PFA_SPREAD_SLAB			2	/* Spread some slab caches over cpuset */
1691#define PFA_SPEC_SSB_DISABLE		3	/* Speculative Store Bypass disabled */
1692#define PFA_SPEC_SSB_FORCE_DISABLE	4	/* Speculative Store Bypass force disabled*/
1693#define PFA_SPEC_IB_DISABLE		5	/* Indirect branch speculation restricted */
1694#define PFA_SPEC_IB_FORCE_DISABLE	6	/* Indirect branch speculation permanently restricted */
1695#define PFA_SPEC_SSB_NOEXEC		7	/* Speculative Store Bypass clear on execve() */
1696
1697#define TASK_PFA_TEST(name, func)					\
1698	static inline bool task_##func(struct task_struct *p)		\
1699	{ return test_bit(PFA_##name, &p->atomic_flags); }
1700
1701#define TASK_PFA_SET(name, func)					\
1702	static inline void task_set_##func(struct task_struct *p)	\
1703	{ set_bit(PFA_##name, &p->atomic_flags); }
1704
1705#define TASK_PFA_CLEAR(name, func)					\
1706	static inline void task_clear_##func(struct task_struct *p)	\
1707	{ clear_bit(PFA_##name, &p->atomic_flags); }
1708
1709TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1710TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1711
1712TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1713TASK_PFA_SET(SPREAD_PAGE, spread_page)
1714TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1715
1716TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1717TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1718TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1719
1720TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1721TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1722TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1723
1724TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1725TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1726TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1727
1728TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1729TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1730
1731TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1732TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1733TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1734
1735TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1736TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1737
1738static inline void
1739current_restore_flags(unsigned long orig_flags, unsigned long flags)
1740{
1741	current->flags &= ~flags;
1742	current->flags |= orig_flags & flags;
1743}
1744
1745extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1746extern int task_can_attach(struct task_struct *p);
1747extern int dl_bw_alloc(int cpu, u64 dl_bw);
1748extern void dl_bw_free(int cpu, u64 dl_bw);
1749#ifdef CONFIG_SMP
 
 
1750
1751/* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */
1752extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1753
1754/**
1755 * set_cpus_allowed_ptr - set CPU affinity mask of a task
1756 * @p: the task
1757 * @new_mask: CPU affinity mask
1758 *
1759 * Return: zero if successful, or a negative error code
1760 */
1761extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1762extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1763extern void release_user_cpus_ptr(struct task_struct *p);
1764extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1765extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1766extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1767#else
1768static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
 
1769{
1770}
1771static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
 
1772{
1773	if (!cpumask_test_cpu(0, new_mask))
1774		return -EINVAL;
1775	return 0;
1776}
1777static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1778{
1779	if (src->user_cpus_ptr)
1780		return -EINVAL;
1781	return 0;
1782}
1783static inline void release_user_cpus_ptr(struct task_struct *p)
 
1784{
1785	WARN_ON(p->user_cpus_ptr);
1786}
1787
1788static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1789{
1790	return 0;
1791}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1792#endif
1793
1794extern int yield_to(struct task_struct *p, bool preempt);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1795extern void set_user_nice(struct task_struct *p, long nice);
1796extern int task_prio(const struct task_struct *p);
1797
1798/**
1799 * task_nice - return the nice value of a given task.
1800 * @p: the task in question.
1801 *
1802 * Return: The nice value [ -20 ... 0 ... 19 ].
1803 */
1804static inline int task_nice(const struct task_struct *p)
1805{
1806	return PRIO_TO_NICE((p)->static_prio);
1807}
1808
1809extern int can_nice(const struct task_struct *p, const int nice);
1810extern int task_curr(const struct task_struct *p);
1811extern int idle_cpu(int cpu);
1812extern int available_idle_cpu(int cpu);
1813extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1814extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1815extern void sched_set_fifo(struct task_struct *p);
1816extern void sched_set_fifo_low(struct task_struct *p);
1817extern void sched_set_normal(struct task_struct *p, int nice);
1818extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1819extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1820extern struct task_struct *idle_task(int cpu);
1821
1822/**
1823 * is_idle_task - is the specified task an idle task?
1824 * @p: the task in question.
1825 *
1826 * Return: 1 if @p is an idle task. 0 otherwise.
1827 */
1828static __always_inline bool is_idle_task(const struct task_struct *p)
1829{
1830	return !!(p->flags & PF_IDLE);
1831}
1832
1833extern struct task_struct *curr_task(int cpu);
1834extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1835
1836void yield(void);
1837
 
 
 
 
 
1838union thread_union {
1839	struct task_struct task;
1840#ifndef CONFIG_THREAD_INFO_IN_TASK
1841	struct thread_info thread_info;
1842#endif
1843	unsigned long stack[THREAD_SIZE/sizeof(long)];
1844};
1845
1846#ifndef CONFIG_THREAD_INFO_IN_TASK
1847extern struct thread_info init_thread_info;
 
 
 
 
 
 
1848#endif
1849
1850extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
 
1851
1852#ifdef CONFIG_THREAD_INFO_IN_TASK
1853# define task_thread_info(task)	(&(task)->thread_info)
1854#elif !defined(__HAVE_THREAD_FUNCTIONS)
1855# define task_thread_info(task)	((struct thread_info *)(task)->stack)
1856#endif
1857
1858/*
1859 * find a task by one of its numerical ids
1860 *
1861 * find_task_by_pid_ns():
1862 *      finds a task by its pid in the specified namespace
1863 * find_task_by_vpid():
1864 *      finds a task by its virtual pid
1865 *
1866 * see also find_vpid() etc in include/linux/pid.h
1867 */
1868
1869extern struct task_struct *find_task_by_vpid(pid_t nr);
1870extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
 
 
 
 
 
 
 
 
 
 
 
 
1871
1872/*
1873 * find a task by its virtual pid and get the task struct
1874 */
1875extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1876
1877extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1878extern int wake_up_process(struct task_struct *tsk);
1879extern void wake_up_new_task(struct task_struct *tsk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1880
1881#ifdef CONFIG_SMP
1882extern void kick_process(struct task_struct *tsk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1883#else
1884static inline void kick_process(struct task_struct *tsk) { }
 
1885#endif
 
1886
1887extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
 
 
 
 
1888
1889static inline void set_task_comm(struct task_struct *tsk, const char *from)
1890{
1891	__set_task_comm(tsk, from, false);
 
 
 
 
 
 
1892}
1893
1894extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1895#define get_task_comm(buf, tsk) ({			\
1896	BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN);	\
1897	__get_task_comm(buf, sizeof(buf), tsk);		\
1898})
1899
1900#ifdef CONFIG_SMP
1901static __always_inline void scheduler_ipi(void)
 
1902{
1903	/*
1904	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1905	 * TIF_NEED_RESCHED remotely (for the first time) will also send
1906	 * this IPI.
1907	 */
1908	preempt_fold_need_resched();
1909}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1910#else
1911static inline void scheduler_ipi(void) { }
 
 
 
 
 
1912#endif
1913
1914extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
 
 
 
 
 
 
1915
1916/*
1917 * Set thread flags in other task's structures.
1918 * See asm/thread_info.h for TIF_xxxx flags available:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1919 */
1920static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1921{
1922	set_ti_thread_flag(task_thread_info(tsk), flag);
1923}
1924
1925static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1926{
1927	clear_ti_thread_flag(task_thread_info(tsk), flag);
1928}
1929
1930static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
1931					  bool value)
1932{
1933	update_ti_thread_flag(task_thread_info(tsk), flag, value);
1934}
1935
1936static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1937{
1938	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1939}
1940
1941static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1942{
1943	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1944}
1945
1946static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1947{
1948	return test_ti_thread_flag(task_thread_info(tsk), flag);
1949}
1950
1951static inline void set_tsk_need_resched(struct task_struct *tsk)
1952{
1953	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1954}
1955
1956static inline void clear_tsk_need_resched(struct task_struct *tsk)
1957{
1958	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1959}
1960
1961static inline int test_tsk_need_resched(struct task_struct *tsk)
1962{
1963	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1964}
1965
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1966/*
1967 * cond_resched() and cond_resched_lock(): latency reduction via
1968 * explicit rescheduling in places that are safe. The return
1969 * value indicates whether a reschedule was done in fact.
1970 * cond_resched_lock() will drop the spinlock before scheduling,
 
1971 */
1972#if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
1973extern int __cond_resched(void);
1974
1975#if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
 
 
 
1976
1977void sched_dynamic_klp_enable(void);
1978void sched_dynamic_klp_disable(void);
1979
1980DECLARE_STATIC_CALL(cond_resched, __cond_resched);
 
 
 
 
1981
1982static __always_inline int _cond_resched(void)
1983{
1984	return static_call_mod(cond_resched)();
1985}
1986
1987#elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
1988
1989extern int dynamic_cond_resched(void);
 
 
 
1990
1991static __always_inline int _cond_resched(void)
1992{
1993	return dynamic_cond_resched();
 
 
 
 
1994}
1995
1996#else /* !CONFIG_PREEMPTION */
 
 
 
 
 
 
 
 
 
 
 
 
1997
1998static inline int _cond_resched(void)
 
 
 
 
 
 
 
 
 
 
 
1999{
2000	klp_sched_try_switch();
2001	return __cond_resched();
2002}
2003
2004#endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */
 
 
 
 
 
 
 
 
2005
2006#else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */
 
2007
2008static inline int _cond_resched(void)
2009{
2010	klp_sched_try_switch();
2011	return 0;
2012}
2013
2014#endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */
 
 
2015
2016#define cond_resched() ({			\
2017	__might_resched(__FILE__, __LINE__, 0);	\
2018	_cond_resched();			\
2019})
 
 
 
 
 
 
 
 
 
2020
2021extern int __cond_resched_lock(spinlock_t *lock);
2022extern int __cond_resched_rwlock_read(rwlock_t *lock);
2023extern int __cond_resched_rwlock_write(rwlock_t *lock);
 
2024
2025#define MIGHT_RESCHED_RCU_SHIFT		8
2026#define MIGHT_RESCHED_PREEMPT_MASK	((1U << MIGHT_RESCHED_RCU_SHIFT) - 1)
 
2027
2028#ifndef CONFIG_PREEMPT_RT
2029/*
2030 * Non RT kernels have an elevated preempt count due to the held lock,
2031 * but are not allowed to be inside a RCU read side critical section
2032 */
2033# define PREEMPT_LOCK_RESCHED_OFFSETS	PREEMPT_LOCK_OFFSET
2034#else
2035/*
2036 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in
2037 * cond_resched*lock() has to take that into account because it checks for
2038 * preempt_count() and rcu_preempt_depth().
2039 */
2040# define PREEMPT_LOCK_RESCHED_OFFSETS	\
2041	(PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT))
2042#endif
2043
2044#define cond_resched_lock(lock) ({						\
2045	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2046	__cond_resched_lock(lock);						\
2047})
2048
2049#define cond_resched_rwlock_read(lock) ({					\
2050	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2051	__cond_resched_rwlock_read(lock);					\
2052})
2053
2054#define cond_resched_rwlock_write(lock) ({					\
2055	__might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS);	\
2056	__cond_resched_rwlock_write(lock);					\
2057})
2058
2059#ifdef CONFIG_PREEMPT_DYNAMIC
 
 
 
 
2060
2061extern bool preempt_model_none(void);
2062extern bool preempt_model_voluntary(void);
2063extern bool preempt_model_full(void);
2064
2065#else
 
 
 
2066
2067static inline bool preempt_model_none(void)
 
 
 
 
2068{
2069	return IS_ENABLED(CONFIG_PREEMPT_NONE);
2070}
2071static inline bool preempt_model_voluntary(void)
 
 
2072{
2073	return IS_ENABLED(CONFIG_PREEMPT_VOLUNTARY);
 
 
 
 
 
 
 
 
 
 
2074}
2075static inline bool preempt_model_full(void)
 
2076{
2077	return IS_ENABLED(CONFIG_PREEMPT);
2078}
2079
2080#endif
 
 
 
 
2081
2082static inline bool preempt_model_rt(void)
2083{
2084	return IS_ENABLED(CONFIG_PREEMPT_RT);
2085}
2086
2087/*
2088 * Does the preemption model allow non-cooperative preemption?
2089 *
2090 * For !CONFIG_PREEMPT_DYNAMIC kernels this is an exact match with
2091 * CONFIG_PREEMPTION; for CONFIG_PREEMPT_DYNAMIC this doesn't work as the
2092 * kernel is *built* with CONFIG_PREEMPTION=y but may run with e.g. the
2093 * PREEMPT_NONE model.
2094 */
2095static inline bool preempt_model_preemptible(void)
 
 
 
 
 
2096{
2097	return preempt_model_full() || preempt_model_rt();
2098}
2099
2100static __always_inline bool need_resched(void)
2101{
2102	return unlikely(tif_need_resched());
2103}
2104
2105/*
2106 * Wrappers for p->thread_info->cpu access. No-op on UP.
2107 */
2108#ifdef CONFIG_SMP
2109
2110static inline unsigned int task_cpu(const struct task_struct *p)
2111{
2112	return READ_ONCE(task_thread_info(p)->cpu);
 
 
 
 
 
2113}
2114
2115extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2116
2117#else
2118
2119static inline unsigned int task_cpu(const struct task_struct *p)
2120{
2121	return 0;
2122}
2123
2124static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2125{
2126}
2127
2128#endif /* CONFIG_SMP */
2129
2130extern bool sched_task_on_rq(struct task_struct *p);
2131extern unsigned long get_wchan(struct task_struct *p);
2132extern struct task_struct *cpu_curr_snapshot(int cpu);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2133
2134#include <linux/spinlock.h>
 
 
2135
2136/*
2137 * In order to reduce various lock holder preemption latencies provide an
2138 * interface to see if a vCPU is currently running or not.
2139 *
2140 * This allows us to terminate optimistic spin loops and block, analogous to
2141 * the native optimistic spin heuristic of testing if the lock owner task is
2142 * running or not.
2143 */
2144#ifndef vcpu_is_preempted
2145static inline bool vcpu_is_preempted(int cpu)
2146{
2147	return false;
2148}
2149#endif
2150
2151extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2152extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2153
2154#ifndef TASK_SIZE_OF
2155#define TASK_SIZE_OF(tsk)	TASK_SIZE
2156#endif
2157
2158#ifdef CONFIG_SMP
2159static inline bool owner_on_cpu(struct task_struct *owner)
 
 
 
 
 
 
 
 
 
 
 
 
 
2160{
2161	/*
2162	 * As lock holder preemption issue, we both skip spinning if
2163	 * task is not on cpu or its cpu is preempted
2164	 */
2165	return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner));
2166}
2167
2168/* Returns effective CPU energy utilization, as seen by the scheduler */
2169unsigned long sched_cpu_util(int cpu);
2170#endif /* CONFIG_SMP */
 
 
2171
2172#ifdef CONFIG_SCHED_CORE
2173extern void sched_core_free(struct task_struct *tsk);
2174extern void sched_core_fork(struct task_struct *p);
2175extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2176				unsigned long uaddr);
2177extern int sched_core_idle_cpu(int cpu);
2178#else
2179static inline void sched_core_free(struct task_struct *tsk) { }
2180static inline void sched_core_fork(struct task_struct *p) { }
2181static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
2182#endif
2183
2184extern void sched_set_stop_task(int cpu, struct task_struct *stop);
 
 
 
2185
2186#endif