linux/include/linux/sched.h
<<
>>
Prefs
   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.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/shm.h>
  37#include <linux/signal.h>
  38#include <linux/compiler.h>
  39#include <linux/completion.h>
  40#include <linux/pid.h>
  41#include <linux/percpu.h>
  42#include <linux/topology.h>
  43#include <linux/proportions.h>
  44#include <linux/seccomp.h>
  45#include <linux/rcupdate.h>
  46#include <linux/rculist.h>
  47#include <linux/rtmutex.h>
  48
  49#include <linux/time.h>
  50#include <linux/param.h>
  51#include <linux/resource.h>
  52#include <linux/timer.h>
  53#include <linux/hrtimer.h>
  54#include <linux/task_io_accounting.h>
  55#include <linux/latencytop.h>
  56#include <linux/cred.h>
  57#include <linux/llist.h>
  58#include <linux/uidgid.h>
  59#include <linux/gfp.h>
  60#include <linux/magic.h>
  61#include <linux/cgroup-defs.h>
  62
  63#include <asm/processor.h>
  64
  65#define SCHED_ATTR_SIZE_VER0    48      /* sizeof first published struct */
  66
  67/*
  68 * Extended scheduling parameters data structure.
  69 *
  70 * This is needed because the original struct sched_param can not be
  71 * altered without introducing ABI issues with legacy applications
  72 * (e.g., in sched_getparam()).
  73 *
  74 * However, the possibility of specifying more than just a priority for
  75 * the tasks may be useful for a wide variety of application fields, e.g.,
  76 * multimedia, streaming, automation and control, and many others.
  77 *
  78 * This variant (sched_attr) is meant at describing a so-called
  79 * sporadic time-constrained task. In such model a task is specified by:
  80 *  - the activation period or minimum instance inter-arrival time;
  81 *  - the maximum (or average, depending on the actual scheduling
  82 *    discipline) computation time of all instances, a.k.a. runtime;
  83 *  - the deadline (relative to the actual activation time) of each
  84 *    instance.
  85 * Very briefly, a periodic (sporadic) task asks for the execution of
  86 * some specific computation --which is typically called an instance--
  87 * (at most) every period. Moreover, each instance typically lasts no more
  88 * than the runtime and must be completed by time instant t equal to
  89 * the instance activation time + the deadline.
  90 *
  91 * This is reflected by the actual fields of the sched_attr structure:
  92 *
  93 *  @size               size of the structure, for fwd/bwd compat.
  94 *
  95 *  @sched_policy       task's scheduling policy
  96 *  @sched_flags        for customizing the scheduler behaviour
  97 *  @sched_nice         task's nice value      (SCHED_NORMAL/BATCH)
  98 *  @sched_priority     task's static priority (SCHED_FIFO/RR)
  99 *  @sched_deadline     representative of the task's deadline
 100 *  @sched_runtime      representative of the task's runtime
 101 *  @sched_period       representative of the task's period
 102 *
 103 * Given this task model, there are a multiplicity of scheduling algorithms
 104 * and policies, that can be used to ensure all the tasks will make their
 105 * timing constraints.
 106 *
 107 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
 108 * only user of this new interface. More information about the algorithm
 109 * available in the scheduling class file or in Documentation/.
 110 */
 111struct sched_attr {
 112        u32 size;
 113
 114        u32 sched_policy;
 115        u64 sched_flags;
 116
 117        /* SCHED_NORMAL, SCHED_BATCH */
 118        s32 sched_nice;
 119
 120        /* SCHED_FIFO, SCHED_RR */
 121        u32 sched_priority;
 122
 123        /* SCHED_DEADLINE */
 124        u64 sched_runtime;
 125        u64 sched_deadline;
 126        u64 sched_period;
 127};
 128
 129struct futex_pi_state;
 130struct robust_list_head;
 131struct bio_list;
 132struct fs_struct;
 133struct perf_event_context;
 134struct blk_plug;
 135struct filename;
 136struct nameidata;
 137
 138#define VMACACHE_BITS 2
 139#define VMACACHE_SIZE (1U << VMACACHE_BITS)
 140#define VMACACHE_MASK (VMACACHE_SIZE - 1)
 141
 142/*
 143 * These are the constant used to fake the fixed-point load-average
 144 * counting. Some notes:
 145 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 146 *    a load-average precision of 10 bits integer + 11 bits fractional
 147 *  - if you want to count load-averages more often, you need more
 148 *    precision, or rounding will get you. With 2-second counting freq,
 149 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 150 *    11 bit fractions.
 151 */
 152extern unsigned long avenrun[];         /* Load averages */
 153extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
 154
 155#define FSHIFT          11              /* nr of bits of precision */
 156#define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
 157#define LOAD_FREQ       (5*HZ+1)        /* 5 sec intervals */
 158#define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
 159#define EXP_5           2014            /* 1/exp(5sec/5min) */
 160#define EXP_15          2037            /* 1/exp(5sec/15min) */
 161
 162#define CALC_LOAD(load,exp,n) \
 163        load *= exp; \
 164        load += n*(FIXED_1-exp); \
 165        load >>= FSHIFT;
 166
 167extern unsigned long total_forks;
 168extern int nr_threads;
 169DECLARE_PER_CPU(unsigned long, process_counts);
 170extern int nr_processes(void);
 171extern unsigned long nr_running(void);
 172extern bool single_task_running(void);
 173extern unsigned long nr_iowait(void);
 174extern unsigned long nr_iowait_cpu(int cpu);
 175extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
 176
 177extern void calc_global_load(unsigned long ticks);
 178
 179#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
 180extern void update_cpu_load_nohz(void);
 181#else
 182static inline void update_cpu_load_nohz(void) { }
 183#endif
 184
 185extern unsigned long get_parent_ip(unsigned long addr);
 186
 187extern void dump_cpu_task(int cpu);
 188
 189struct seq_file;
 190struct cfs_rq;
 191struct task_group;
 192#ifdef CONFIG_SCHED_DEBUG
 193extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
 194extern void proc_sched_set_task(struct task_struct *p);
 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_NOLOAD             1024
 222#define TASK_STATE_MAX          2048
 223
 224#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN"
 225
 226extern char ___assert_task_state[1 - 2*!!(
 227                sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
 228
 229/* Convenience macros for the sake of set_task_state */
 230#define TASK_KILLABLE           (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
 231#define TASK_STOPPED            (TASK_WAKEKILL | __TASK_STOPPED)
 232#define TASK_TRACED             (TASK_WAKEKILL | __TASK_TRACED)
 233
 234#define TASK_IDLE               (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
 235
 236/* Convenience macros for the sake of wake_up */
 237#define TASK_NORMAL             (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
 238#define TASK_ALL                (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
 239
 240/* get_task_state() */
 241#define TASK_REPORT             (TASK_RUNNING | TASK_INTERRUPTIBLE | \
 242                                 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
 243                                 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
 244
 245#define task_is_traced(task)    ((task->state & __TASK_TRACED) != 0)
 246#define task_is_stopped(task)   ((task->state & __TASK_STOPPED) != 0)
 247#define task_is_stopped_or_traced(task) \
 248                        ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
 249#define task_contributes_to_load(task)  \
 250                                ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
 251                                 (task->flags & PF_FROZEN) == 0 && \
 252                                 (task->state & TASK_NOLOAD) == 0)
 253
 254#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 255
 256#define __set_task_state(tsk, state_value)                      \
 257        do {                                                    \
 258                (tsk)->task_state_change = _THIS_IP_;           \
 259                (tsk)->state = (state_value);                   \
 260        } while (0)
 261#define set_task_state(tsk, state_value)                        \
 262        do {                                                    \
 263                (tsk)->task_state_change = _THIS_IP_;           \
 264                smp_store_mb((tsk)->state, (state_value));              \
 265        } while (0)
 266
 267/*
 268 * set_current_state() includes a barrier so that the write of current->state
 269 * is correctly serialised wrt the caller's subsequent test of whether to
 270 * actually sleep:
 271 *
 272 *      set_current_state(TASK_UNINTERRUPTIBLE);
 273 *      if (do_i_need_to_sleep())
 274 *              schedule();
 275 *
 276 * If the caller does not need such serialisation then use __set_current_state()
 277 */
 278#define __set_current_state(state_value)                        \
 279        do {                                                    \
 280                current->task_state_change = _THIS_IP_;         \
 281                current->state = (state_value);                 \
 282        } while (0)
 283#define set_current_state(state_value)                          \
 284        do {                                                    \
 285                current->task_state_change = _THIS_IP_;         \
 286                smp_store_mb(current->state, (state_value));            \
 287        } while (0)
 288
 289#else
 290
 291#define __set_task_state(tsk, state_value)              \
 292        do { (tsk)->state = (state_value); } while (0)
 293#define set_task_state(tsk, state_value)                \
 294        smp_store_mb((tsk)->state, (state_value))
 295
 296/*
 297 * set_current_state() includes a barrier so that the write of current->state
 298 * is correctly serialised wrt the caller's subsequent test of whether to
 299 * actually sleep:
 300 *
 301 *      set_current_state(TASK_UNINTERRUPTIBLE);
 302 *      if (do_i_need_to_sleep())
 303 *              schedule();
 304 *
 305 * If the caller does not need such serialisation then use __set_current_state()
 306 */
 307#define __set_current_state(state_value)                \
 308        do { current->state = (state_value); } while (0)
 309#define set_current_state(state_value)                  \
 310        smp_store_mb(current->state, (state_value))
 311
 312#endif
 313
 314/* Task command name length */
 315#define TASK_COMM_LEN 16
 316
 317#include <linux/spinlock.h>
 318
 319/*
 320 * This serializes "schedule()" and also protects
 321 * the run-queue from deletions/modifications (but
 322 * _adding_ to the beginning of the run-queue has
 323 * a separate lock).
 324 */
 325extern rwlock_t tasklist_lock;
 326extern spinlock_t mmlist_lock;
 327
 328struct task_struct;
 329
 330#ifdef CONFIG_PROVE_RCU
 331extern int lockdep_tasklist_lock_is_held(void);
 332#endif /* #ifdef CONFIG_PROVE_RCU */
 333
 334extern void sched_init(void);
 335extern void sched_init_smp(void);
 336extern asmlinkage void schedule_tail(struct task_struct *prev);
 337extern void init_idle(struct task_struct *idle, int cpu);
 338extern void init_idle_bootup_task(struct task_struct *idle);
 339
 340extern cpumask_var_t cpu_isolated_map;
 341
 342extern int runqueue_is_locked(int cpu);
 343
 344#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
 345extern void nohz_balance_enter_idle(int cpu);
 346extern void set_cpu_sd_state_idle(void);
 347extern int get_nohz_timer_target(void);
 348#else
 349static inline void nohz_balance_enter_idle(int cpu) { }
 350static inline void set_cpu_sd_state_idle(void) { }
 351#endif
 352
 353/*
 354 * Only dump TASK_* tasks. (0 for all tasks)
 355 */
 356extern void show_state_filter(unsigned long state_filter);
 357
 358static inline void show_state(void)
 359{
 360        show_state_filter(0);
 361}
 362
 363extern void show_regs(struct pt_regs *);
 364
 365/*
 366 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 367 * task), SP is the stack pointer of the first frame that should be shown in the back
 368 * trace (or NULL if the entire call-chain of the task should be shown).
 369 */
 370extern void show_stack(struct task_struct *task, unsigned long *sp);
 371
 372extern void cpu_init (void);
 373extern void trap_init(void);
 374extern void update_process_times(int user);
 375extern void scheduler_tick(void);
 376
 377extern void sched_show_task(struct task_struct *p);
 378
 379#ifdef CONFIG_LOCKUP_DETECTOR
 380extern void touch_softlockup_watchdog(void);
 381extern void touch_softlockup_watchdog_sync(void);
 382extern void touch_all_softlockup_watchdogs(void);
 383extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
 384                                  void __user *buffer,
 385                                  size_t *lenp, loff_t *ppos);
 386extern unsigned int  softlockup_panic;
 387extern unsigned int  hardlockup_panic;
 388void lockup_detector_init(void);
 389#else
 390static inline void touch_softlockup_watchdog(void)
 391{
 392}
 393static inline void touch_softlockup_watchdog_sync(void)
 394{
 395}
 396static inline void touch_all_softlockup_watchdogs(void)
 397{
 398}
 399static inline void lockup_detector_init(void)
 400{
 401}
 402#endif
 403
 404#ifdef CONFIG_DETECT_HUNG_TASK
 405void reset_hung_task_detector(void);
 406#else
 407static inline void reset_hung_task_detector(void)
 408{
 409}
 410#endif
 411
 412/* Attach to any functions which should be ignored in wchan output. */
 413#define __sched         __attribute__((__section__(".sched.text")))
 414
 415/* Linker adds these: start and end of __sched functions */
 416extern char __sched_text_start[], __sched_text_end[];
 417
 418/* Is this address in the __sched functions? */
 419extern int in_sched_functions(unsigned long addr);
 420
 421#define MAX_SCHEDULE_TIMEOUT    LONG_MAX
 422extern signed long schedule_timeout(signed long timeout);
 423extern signed long schedule_timeout_interruptible(signed long timeout);
 424extern signed long schedule_timeout_killable(signed long timeout);
 425extern signed long schedule_timeout_uninterruptible(signed long timeout);
 426asmlinkage void schedule(void);
 427extern void schedule_preempt_disabled(void);
 428
 429extern long io_schedule_timeout(long timeout);
 430
 431static inline void io_schedule(void)
 432{
 433        io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
 434}
 435
 436struct nsproxy;
 437struct user_namespace;
 438
 439#ifdef CONFIG_MMU
 440extern void arch_pick_mmap_layout(struct mm_struct *mm);
 441extern unsigned long
 442arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
 443                       unsigned long, unsigned long);
 444extern unsigned long
 445arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 446                          unsigned long len, unsigned long pgoff,
 447                          unsigned long flags);
 448#else
 449static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
 450#endif
 451
 452#define SUID_DUMP_DISABLE       0       /* No setuid dumping */
 453#define SUID_DUMP_USER          1       /* Dump as user of process */
 454#define SUID_DUMP_ROOT          2       /* Dump as root */
 455
 456/* mm flags */
 457
 458/* for SUID_DUMP_* above */
 459#define MMF_DUMPABLE_BITS 2
 460#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
 461
 462extern void set_dumpable(struct mm_struct *mm, int value);
 463/*
 464 * This returns the actual value of the suid_dumpable flag. For things
 465 * that are using this for checking for privilege transitions, it must
 466 * test against SUID_DUMP_USER rather than treating it as a boolean
 467 * value.
 468 */
 469static inline int __get_dumpable(unsigned long mm_flags)
 470{
 471        return mm_flags & MMF_DUMPABLE_MASK;
 472}
 473
 474static inline int get_dumpable(struct mm_struct *mm)
 475{
 476        return __get_dumpable(mm->flags);
 477}
 478
 479/* coredump filter bits */
 480#define MMF_DUMP_ANON_PRIVATE   2
 481#define MMF_DUMP_ANON_SHARED    3
 482#define MMF_DUMP_MAPPED_PRIVATE 4
 483#define MMF_DUMP_MAPPED_SHARED  5
 484#define MMF_DUMP_ELF_HEADERS    6
 485#define MMF_DUMP_HUGETLB_PRIVATE 7
 486#define MMF_DUMP_HUGETLB_SHARED  8
 487#define MMF_DUMP_DAX_PRIVATE    9
 488#define MMF_DUMP_DAX_SHARED     10
 489
 490#define MMF_DUMP_FILTER_SHIFT   MMF_DUMPABLE_BITS
 491#define MMF_DUMP_FILTER_BITS    9
 492#define MMF_DUMP_FILTER_MASK \
 493        (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
 494#define MMF_DUMP_FILTER_DEFAULT \
 495        ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
 496         (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
 497
 498#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
 499# define MMF_DUMP_MASK_DEFAULT_ELF      (1 << MMF_DUMP_ELF_HEADERS)
 500#else
 501# define MMF_DUMP_MASK_DEFAULT_ELF      0
 502#endif
 503                                        /* leave room for more dump flags */
 504#define MMF_VM_MERGEABLE        16      /* KSM may merge identical pages */
 505#define MMF_VM_HUGEPAGE         17      /* set when VM_HUGEPAGE is set on vma */
 506#define MMF_EXE_FILE_CHANGED    18      /* see prctl_set_mm_exe_file() */
 507
 508#define MMF_HAS_UPROBES         19      /* has uprobes */
 509#define MMF_RECALC_UPROBES      20      /* MMF_HAS_UPROBES can be wrong */
 510
 511#define MMF_INIT_MASK           (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
 512
 513struct sighand_struct {
 514        atomic_t                count;
 515        struct k_sigaction      action[_NSIG];
 516        spinlock_t              siglock;
 517        wait_queue_head_t       signalfd_wqh;
 518};
 519
 520struct pacct_struct {
 521        int                     ac_flag;
 522        long                    ac_exitcode;
 523        unsigned long           ac_mem;
 524        cputime_t               ac_utime, ac_stime;
 525        unsigned long           ac_minflt, ac_majflt;
 526};
 527
 528struct cpu_itimer {
 529        cputime_t expires;
 530        cputime_t incr;
 531        u32 error;
 532        u32 incr_error;
 533};
 534
 535/**
 536 * struct prev_cputime - snaphsot of system and user cputime
 537 * @utime: time spent in user mode
 538 * @stime: time spent in system mode
 539 * @lock: protects the above two fields
 540 *
 541 * Stores previous user/system time values such that we can guarantee
 542 * monotonicity.
 543 */
 544struct prev_cputime {
 545#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 546        cputime_t utime;
 547        cputime_t stime;
 548        raw_spinlock_t lock;
 549#endif
 550};
 551
 552static inline void prev_cputime_init(struct prev_cputime *prev)
 553{
 554#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 555        prev->utime = prev->stime = 0;
 556        raw_spin_lock_init(&prev->lock);
 557#endif
 558}
 559
 560/**
 561 * struct task_cputime - collected CPU time counts
 562 * @utime:              time spent in user mode, in &cputime_t units
 563 * @stime:              time spent in kernel mode, in &cputime_t units
 564 * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
 565 *
 566 * This structure groups together three kinds of CPU time that are tracked for
 567 * threads and thread groups.  Most things considering CPU time want to group
 568 * these counts together and treat all three of them in parallel.
 569 */
 570struct task_cputime {
 571        cputime_t utime;
 572        cputime_t stime;
 573        unsigned long long sum_exec_runtime;
 574};
 575
 576/* Alternate field names when used to cache expirations. */
 577#define virt_exp        utime
 578#define prof_exp        stime
 579#define sched_exp       sum_exec_runtime
 580
 581#define INIT_CPUTIME    \
 582        (struct task_cputime) {                                 \
 583                .utime = 0,                                     \
 584                .stime = 0,                                     \
 585                .sum_exec_runtime = 0,                          \
 586        }
 587
 588/*
 589 * This is the atomic variant of task_cputime, which can be used for
 590 * storing and updating task_cputime statistics without locking.
 591 */
 592struct task_cputime_atomic {
 593        atomic64_t utime;
 594        atomic64_t stime;
 595        atomic64_t sum_exec_runtime;
 596};
 597
 598#define INIT_CPUTIME_ATOMIC \
 599        (struct task_cputime_atomic) {                          \
 600                .utime = ATOMIC64_INIT(0),                      \
 601                .stime = ATOMIC64_INIT(0),                      \
 602                .sum_exec_runtime = ATOMIC64_INIT(0),           \
 603        }
 604
 605#define PREEMPT_DISABLED        (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
 606
 607/*
 608 * Disable preemption until the scheduler is running -- use an unconditional
 609 * value so that it also works on !PREEMPT_COUNT kernels.
 610 *
 611 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
 612 */
 613#define INIT_PREEMPT_COUNT      PREEMPT_OFFSET
 614
 615/*
 616 * Initial preempt_count value; reflects the preempt_count schedule invariant
 617 * which states that during context switches:
 618 *
 619 *    preempt_count() == 2*PREEMPT_DISABLE_OFFSET
 620 *
 621 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
 622 * Note: See finish_task_switch().
 623 */
 624#define FORK_PREEMPT_COUNT      (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
 625
 626/**
 627 * struct thread_group_cputimer - thread group interval timer counts
 628 * @cputime_atomic:     atomic thread group interval timers.
 629 * @running:            true when there are timers running and
 630 *                      @cputime_atomic receives updates.
 631 * @checking_timer:     true when a thread in the group is in the
 632 *                      process of checking for thread group timers.
 633 *
 634 * This structure contains the version of task_cputime, above, that is
 635 * used for thread group CPU timer calculations.
 636 */
 637struct thread_group_cputimer {
 638        struct task_cputime_atomic cputime_atomic;
 639        bool running;
 640        bool checking_timer;
 641};
 642
 643#include <linux/rwsem.h>
 644struct autogroup;
 645
 646/*
 647 * NOTE! "signal_struct" does not have its own
 648 * locking, because a shared signal_struct always
 649 * implies a shared sighand_struct, so locking
 650 * sighand_struct is always a proper superset of
 651 * the locking of signal_struct.
 652 */
 653struct signal_struct {
 654        atomic_t                sigcnt;
 655        atomic_t                live;
 656        int                     nr_threads;
 657        struct list_head        thread_head;
 658
 659        wait_queue_head_t       wait_chldexit;  /* for wait4() */
 660
 661        /* current thread group signal load-balancing target: */
 662        struct task_struct      *curr_target;
 663
 664        /* shared signal handling: */
 665        struct sigpending       shared_pending;
 666
 667        /* thread group exit support */
 668        int                     group_exit_code;
 669        /* overloaded:
 670         * - notify group_exit_task when ->count is equal to notify_count
 671         * - everyone except group_exit_task is stopped during signal delivery
 672         *   of fatal signals, group_exit_task processes the signal.
 673         */
 674        int                     notify_count;
 675        struct task_struct      *group_exit_task;
 676
 677        /* thread group stop support, overloads group_exit_code too */
 678        int                     group_stop_count;
 679        unsigned int            flags; /* see SIGNAL_* flags below */
 680
 681        /*
 682         * PR_SET_CHILD_SUBREAPER marks a process, like a service
 683         * manager, to re-parent orphan (double-forking) child processes
 684         * to this process instead of 'init'. The service manager is
 685         * able to receive SIGCHLD signals and is able to investigate
 686         * the process until it calls wait(). All children of this
 687         * process will inherit a flag if they should look for a
 688         * child_subreaper process at exit.
 689         */
 690        unsigned int            is_child_subreaper:1;
 691        unsigned int            has_child_subreaper:1;
 692
 693        /* POSIX.1b Interval Timers */
 694        int                     posix_timer_id;
 695        struct list_head        posix_timers;
 696
 697        /* ITIMER_REAL timer for the process */
 698        struct hrtimer real_timer;
 699        struct pid *leader_pid;
 700        ktime_t it_real_incr;
 701
 702        /*
 703         * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
 704         * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
 705         * values are defined to 0 and 1 respectively
 706         */
 707        struct cpu_itimer it[2];
 708
 709        /*
 710         * Thread group totals for process CPU timers.
 711         * See thread_group_cputimer(), et al, for details.
 712         */
 713        struct thread_group_cputimer cputimer;
 714
 715        /* Earliest-expiration cache. */
 716        struct task_cputime cputime_expires;
 717
 718        struct list_head cpu_timers[3];
 719
 720        struct pid *tty_old_pgrp;
 721
 722        /* boolean value for session group leader */
 723        int leader;
 724
 725        struct tty_struct *tty; /* NULL if no tty */
 726
 727#ifdef CONFIG_SCHED_AUTOGROUP
 728        struct autogroup *autogroup;
 729#endif
 730        /*
 731         * Cumulative resource counters for dead threads in the group,
 732         * and for reaped dead child processes forked by this group.
 733         * Live threads maintain their own counters and add to these
 734         * in __exit_signal, except for the group leader.
 735         */
 736        seqlock_t stats_lock;
 737        cputime_t utime, stime, cutime, cstime;
 738        cputime_t gtime;
 739        cputime_t cgtime;
 740        struct prev_cputime prev_cputime;
 741        unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 742        unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 743        unsigned long inblock, oublock, cinblock, coublock;
 744        unsigned long maxrss, cmaxrss;
 745        struct task_io_accounting ioac;
 746
 747        /*
 748         * Cumulative ns of schedule CPU time fo dead threads in the
 749         * group, not including a zombie group leader, (This only differs
 750         * from jiffies_to_ns(utime + stime) if sched_clock uses something
 751         * other than jiffies.)
 752         */
 753        unsigned long long sum_sched_runtime;
 754
 755        /*
 756         * We don't bother to synchronize most readers of this at all,
 757         * because there is no reader checking a limit that actually needs
 758         * to get both rlim_cur and rlim_max atomically, and either one
 759         * alone is a single word that can safely be read normally.
 760         * getrlimit/setrlimit use task_lock(current->group_leader) to
 761         * protect this instead of the siglock, because they really
 762         * have no need to disable irqs.
 763         */
 764        struct rlimit rlim[RLIM_NLIMITS];
 765
 766#ifdef CONFIG_BSD_PROCESS_ACCT
 767        struct pacct_struct pacct;      /* per-process accounting information */
 768#endif
 769#ifdef CONFIG_TASKSTATS
 770        struct taskstats *stats;
 771#endif
 772#ifdef CONFIG_AUDIT
 773        unsigned audit_tty;
 774        unsigned audit_tty_log_passwd;
 775        struct tty_audit_buf *tty_audit_buf;
 776#endif
 777
 778        oom_flags_t oom_flags;
 779        short oom_score_adj;            /* OOM kill score adjustment */
 780        short oom_score_adj_min;        /* OOM kill score adjustment min value.
 781                                         * Only settable by CAP_SYS_RESOURCE. */
 782
 783        struct mutex cred_guard_mutex;  /* guard against foreign influences on
 784                                         * credential calculations
 785                                         * (notably. ptrace) */
 786};
 787
 788/*
 789 * Bits in flags field of signal_struct.
 790 */
 791#define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
 792#define SIGNAL_STOP_CONTINUED   0x00000002 /* SIGCONT since WCONTINUED reap */
 793#define SIGNAL_GROUP_EXIT       0x00000004 /* group exit in progress */
 794#define SIGNAL_GROUP_COREDUMP   0x00000008 /* coredump in progress */
 795/*
 796 * Pending notifications to parent.
 797 */
 798#define SIGNAL_CLD_STOPPED      0x00000010
 799#define SIGNAL_CLD_CONTINUED    0x00000020
 800#define SIGNAL_CLD_MASK         (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
 801
 802#define SIGNAL_UNKILLABLE       0x00000040 /* for init: ignore fatal signals */
 803
 804/* If true, all threads except ->group_exit_task have pending SIGKILL */
 805static inline int signal_group_exit(const struct signal_struct *sig)
 806{
 807        return  (sig->flags & SIGNAL_GROUP_EXIT) ||
 808                (sig->group_exit_task != NULL);
 809}
 810
 811/*
 812 * Some day this will be a full-fledged user tracking system..
 813 */
 814struct user_struct {
 815        atomic_t __count;       /* reference count */
 816        atomic_t processes;     /* How many processes does this user have? */
 817        atomic_t sigpending;    /* How many pending signals does this user have? */
 818#ifdef CONFIG_INOTIFY_USER
 819        atomic_t inotify_watches; /* How many inotify watches does this user have? */
 820        atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
 821#endif
 822#ifdef CONFIG_FANOTIFY
 823        atomic_t fanotify_listeners;
 824#endif
 825#ifdef CONFIG_EPOLL
 826        atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
 827#endif
 828#ifdef CONFIG_POSIX_MQUEUE
 829        /* protected by mq_lock */
 830        unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
 831#endif
 832        unsigned long locked_shm; /* How many pages of mlocked shm ? */
 833
 834#ifdef CONFIG_KEYS
 835        struct key *uid_keyring;        /* UID specific keyring */
 836        struct key *session_keyring;    /* UID's default session keyring */
 837#endif
 838
 839        /* Hash table maintenance information */
 840        struct hlist_node uidhash_node;
 841        kuid_t uid;
 842
 843#if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
 844        atomic_long_t locked_vm;
 845#endif
 846};
 847
 848extern int uids_sysfs_init(void);
 849
 850extern struct user_struct *find_user(kuid_t);
 851
 852extern struct user_struct root_user;
 853#define INIT_USER (&root_user)
 854
 855
 856struct backing_dev_info;
 857struct reclaim_state;
 858
 859#ifdef CONFIG_SCHED_INFO
 860struct sched_info {
 861        /* cumulative counters */
 862        unsigned long pcount;         /* # of times run on this cpu */
 863        unsigned long long run_delay; /* time spent waiting on a runqueue */
 864
 865        /* timestamps */
 866        unsigned long long last_arrival,/* when we last ran on a cpu */
 867                           last_queued; /* when we were last queued to run */
 868};
 869#endif /* CONFIG_SCHED_INFO */
 870
 871#ifdef CONFIG_TASK_DELAY_ACCT
 872struct task_delay_info {
 873        spinlock_t      lock;
 874        unsigned int    flags;  /* Private per-task flags */
 875
 876        /* For each stat XXX, add following, aligned appropriately
 877         *
 878         * struct timespec XXX_start, XXX_end;
 879         * u64 XXX_delay;
 880         * u32 XXX_count;
 881         *
 882         * Atomicity of updates to XXX_delay, XXX_count protected by
 883         * single lock above (split into XXX_lock if contention is an issue).
 884         */
 885
 886        /*
 887         * XXX_count is incremented on every XXX operation, the delay
 888         * associated with the operation is added to XXX_delay.
 889         * XXX_delay contains the accumulated delay time in nanoseconds.
 890         */
 891        u64 blkio_start;        /* Shared by blkio, swapin */
 892        u64 blkio_delay;        /* wait for sync block io completion */
 893        u64 swapin_delay;       /* wait for swapin block io completion */
 894        u32 blkio_count;        /* total count of the number of sync block */
 895                                /* io operations performed */
 896        u32 swapin_count;       /* total count of the number of swapin block */
 897                                /* io operations performed */
 898
 899        u64 freepages_start;
 900        u64 freepages_delay;    /* wait for memory reclaim */
 901        u32 freepages_count;    /* total count of memory reclaim */
 902};
 903#endif  /* CONFIG_TASK_DELAY_ACCT */
 904
 905static inline int sched_info_on(void)
 906{
 907#ifdef CONFIG_SCHEDSTATS
 908        return 1;
 909#elif defined(CONFIG_TASK_DELAY_ACCT)
 910        extern int delayacct_on;
 911        return delayacct_on;
 912#else
 913        return 0;
 914#endif
 915}
 916
 917enum cpu_idle_type {
 918        CPU_IDLE,
 919        CPU_NOT_IDLE,
 920        CPU_NEWLY_IDLE,
 921        CPU_MAX_IDLE_TYPES
 922};
 923
 924/*
 925 * Increase resolution of cpu_capacity calculations
 926 */
 927#define SCHED_CAPACITY_SHIFT    10
 928#define SCHED_CAPACITY_SCALE    (1L << SCHED_CAPACITY_SHIFT)
 929
 930/*
 931 * Wake-queues are lists of tasks with a pending wakeup, whose
 932 * callers have already marked the task as woken internally,
 933 * and can thus carry on. A common use case is being able to
 934 * do the wakeups once the corresponding user lock as been
 935 * released.
 936 *
 937 * We hold reference to each task in the list across the wakeup,
 938 * thus guaranteeing that the memory is still valid by the time
 939 * the actual wakeups are performed in wake_up_q().
 940 *
 941 * One per task suffices, because there's never a need for a task to be
 942 * in two wake queues simultaneously; it is forbidden to abandon a task
 943 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
 944 * already in a wake queue, the wakeup will happen soon and the second
 945 * waker can just skip it.
 946 *
 947 * The WAKE_Q macro declares and initializes the list head.
 948 * wake_up_q() does NOT reinitialize the list; it's expected to be
 949 * called near the end of a function, where the fact that the queue is
 950 * not used again will be easy to see by inspection.
 951 *
 952 * Note that this can cause spurious wakeups. schedule() callers
 953 * must ensure the call is done inside a loop, confirming that the
 954 * wakeup condition has in fact occurred.
 955 */
 956struct wake_q_node {
 957        struct wake_q_node *next;
 958};
 959
 960struct wake_q_head {
 961        struct wake_q_node *first;
 962        struct wake_q_node **lastp;
 963};
 964
 965#define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
 966
 967#define WAKE_Q(name)                                    \
 968        struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
 969
 970extern void wake_q_add(struct wake_q_head *head,
 971                       struct task_struct *task);
 972extern void wake_up_q(struct wake_q_head *head);
 973
 974/*
 975 * sched-domains (multiprocessor balancing) declarations:
 976 */
 977#ifdef CONFIG_SMP
 978#define SD_LOAD_BALANCE         0x0001  /* Do load balancing on this domain. */
 979#define SD_BALANCE_NEWIDLE      0x0002  /* Balance when about to become idle */
 980#define SD_BALANCE_EXEC         0x0004  /* Balance on exec */
 981#define SD_BALANCE_FORK         0x0008  /* Balance on fork, clone */
 982#define SD_BALANCE_WAKE         0x0010  /* Balance on wakeup */
 983#define SD_WAKE_AFFINE          0x0020  /* Wake task to waking CPU */
 984#define SD_SHARE_CPUCAPACITY    0x0080  /* Domain members share cpu power */
 985#define SD_SHARE_POWERDOMAIN    0x0100  /* Domain members share power domain */
 986#define SD_SHARE_PKG_RESOURCES  0x0200  /* Domain members share cpu pkg resources */
 987#define SD_SERIALIZE            0x0400  /* Only a single load balancing instance */
 988#define SD_ASYM_PACKING         0x0800  /* Place busy groups earlier in the domain */
 989#define SD_PREFER_SIBLING       0x1000  /* Prefer to place tasks in a sibling domain */
 990#define SD_OVERLAP              0x2000  /* sched_domains of this level overlap */
 991#define SD_NUMA                 0x4000  /* cross-node balancing */
 992
 993#ifdef CONFIG_SCHED_SMT
 994static inline int cpu_smt_flags(void)
 995{
 996        return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
 997}
 998#endif
 999
1000#ifdef CONFIG_SCHED_MC
1001static inline int cpu_core_flags(void)
1002{
1003        return SD_SHARE_PKG_RESOURCES;
1004}
1005#endif
1006
1007#ifdef CONFIG_NUMA
1008static inline int cpu_numa_flags(void)
1009{
1010        return SD_NUMA;
1011}
1012#endif
1013
1014struct sched_domain_attr {
1015        int relax_domain_level;
1016};
1017
1018#define SD_ATTR_INIT    (struct sched_domain_attr) {    \
1019        .relax_domain_level = -1,                       \
1020}
1021
1022extern int sched_domain_level_max;
1023
1024struct sched_group;
1025
1026struct sched_domain {
1027        /* These fields must be setup */
1028        struct sched_domain *parent;    /* top domain must be null terminated */
1029        struct sched_domain *child;     /* bottom domain must be null terminated */
1030        struct sched_group *groups;     /* the balancing groups of the domain */
1031        unsigned long min_interval;     /* Minimum balance interval ms */
1032        unsigned long max_interval;     /* Maximum balance interval ms */
1033        unsigned int busy_factor;       /* less balancing by factor if busy */
1034        unsigned int imbalance_pct;     /* No balance until over watermark */
1035        unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
1036        unsigned int busy_idx;
1037        unsigned int idle_idx;
1038        unsigned int newidle_idx;
1039        unsigned int wake_idx;
1040        unsigned int forkexec_idx;
1041        unsigned int smt_gain;
1042
1043        int nohz_idle;                  /* NOHZ IDLE status */
1044        int flags;                      /* See SD_* */
1045        int level;
1046
1047        /* Runtime fields. */
1048        unsigned long last_balance;     /* init to jiffies. units in jiffies */
1049        unsigned int balance_interval;  /* initialise to 1. units in ms. */
1050        unsigned int nr_balance_failed; /* initialise to 0 */
1051
1052        /* idle_balance() stats */
1053        u64 max_newidle_lb_cost;
1054        unsigned long next_decay_max_lb_cost;
1055
1056#ifdef CONFIG_SCHEDSTATS
1057        /* load_balance() stats */
1058        unsigned int lb_count[CPU_MAX_IDLE_TYPES];
1059        unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
1060        unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
1061        unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
1062        unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
1063        unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
1064        unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
1065        unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
1066
1067        /* Active load balancing */
1068        unsigned int alb_count;
1069        unsigned int alb_failed;
1070        unsigned int alb_pushed;
1071
1072        /* SD_BALANCE_EXEC stats */
1073        unsigned int sbe_count;
1074        unsigned int sbe_balanced;
1075        unsigned int sbe_pushed;
1076
1077        /* SD_BALANCE_FORK stats */
1078        unsigned int sbf_count;
1079        unsigned int sbf_balanced;
1080        unsigned int sbf_pushed;
1081
1082        /* try_to_wake_up() stats */
1083        unsigned int ttwu_wake_remote;
1084        unsigned int ttwu_move_affine;
1085        unsigned int ttwu_move_balance;
1086#endif
1087#ifdef CONFIG_SCHED_DEBUG
1088        char *name;
1089#endif
1090        union {
1091                void *private;          /* used during construction */
1092                struct rcu_head rcu;    /* used during destruction */
1093        };
1094
1095        unsigned int span_weight;
1096        /*
1097         * Span of all CPUs in this domain.
1098         *
1099         * NOTE: this field is variable length. (Allocated dynamically
1100         * by attaching extra space to the end of the structure,
1101         * depending on how many CPUs the kernel has booted up with)
1102         */
1103        unsigned long span[0];
1104};
1105
1106static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1107{
1108        return to_cpumask(sd->span);
1109}
1110
1111extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1112                                    struct sched_domain_attr *dattr_new);
1113
1114/* Allocate an array of sched domains, for partition_sched_domains(). */
1115cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1116void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1117
1118bool cpus_share_cache(int this_cpu, int that_cpu);
1119
1120typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
1121typedef int (*sched_domain_flags_f)(void);
1122
1123#define SDTL_OVERLAP    0x01
1124
1125struct sd_data {
1126        struct sched_domain **__percpu sd;
1127        struct sched_group **__percpu sg;
1128        struct sched_group_capacity **__percpu sgc;
1129};
1130
1131struct sched_domain_topology_level {
1132        sched_domain_mask_f mask;
1133        sched_domain_flags_f sd_flags;
1134        int                 flags;
1135        int                 numa_level;
1136        struct sd_data      data;
1137#ifdef CONFIG_SCHED_DEBUG
1138        char                *name;
1139#endif
1140};
1141
1142extern void set_sched_topology(struct sched_domain_topology_level *tl);
1143extern void wake_up_if_idle(int cpu);
1144
1145#ifdef CONFIG_SCHED_DEBUG
1146# define SD_INIT_NAME(type)             .name = #type
1147#else
1148# define SD_INIT_NAME(type)
1149#endif
1150
1151#else /* CONFIG_SMP */
1152
1153struct sched_domain_attr;
1154
1155static inline void
1156partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1157                        struct sched_domain_attr *dattr_new)
1158{
1159}
1160
1161static inline bool cpus_share_cache(int this_cpu, int that_cpu)
1162{
1163        return true;
1164}
1165
1166#endif  /* !CONFIG_SMP */
1167
1168
1169struct io_context;                      /* See blkdev.h */
1170
1171
1172#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1173extern void prefetch_stack(struct task_struct *t);
1174#else
1175static inline void prefetch_stack(struct task_struct *t) { }
1176#endif
1177
1178struct audit_context;           /* See audit.c */
1179struct mempolicy;
1180struct pipe_inode_info;
1181struct uts_namespace;
1182
1183struct load_weight {
1184        unsigned long weight;
1185        u32 inv_weight;
1186};
1187
1188/*
1189 * The load_avg/util_avg accumulates an infinite geometric series.
1190 * 1) load_avg factors frequency scaling into the amount of time that a
1191 * sched_entity is runnable on a rq into its weight. For cfs_rq, it is the
1192 * aggregated such weights of all runnable and blocked sched_entities.
1193 * 2) util_avg factors frequency and cpu scaling into the amount of time
1194 * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE].
1195 * For cfs_rq, it is the aggregated such times of all runnable and
1196 * blocked sched_entities.
1197 * The 64 bit load_sum can:
1198 * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with
1199 * the highest weight (=88761) always runnable, we should not overflow
1200 * 2) for entity, support any load.weight always runnable
1201 */
1202struct sched_avg {
1203        u64 last_update_time, load_sum;
1204        u32 util_sum, period_contrib;
1205        unsigned long load_avg, util_avg;
1206};
1207
1208#ifdef CONFIG_SCHEDSTATS
1209struct sched_statistics {
1210        u64                     wait_start;
1211        u64                     wait_max;
1212        u64                     wait_count;
1213        u64                     wait_sum;
1214        u64                     iowait_count;
1215        u64                     iowait_sum;
1216
1217        u64                     sleep_start;
1218        u64                     sleep_max;
1219        s64                     sum_sleep_runtime;
1220
1221        u64                     block_start;
1222        u64                     block_max;
1223        u64                     exec_max;
1224        u64                     slice_max;
1225
1226        u64                     nr_migrations_cold;
1227        u64                     nr_failed_migrations_affine;
1228        u64                     nr_failed_migrations_running;
1229        u64                     nr_failed_migrations_hot;
1230        u64                     nr_forced_migrations;
1231
1232        u64                     nr_wakeups;
1233        u64                     nr_wakeups_sync;
1234        u64                     nr_wakeups_migrate;
1235        u64                     nr_wakeups_local;
1236        u64                     nr_wakeups_remote;
1237        u64                     nr_wakeups_affine;
1238        u64                     nr_wakeups_affine_attempts;
1239        u64                     nr_wakeups_passive;
1240        u64                     nr_wakeups_idle;
1241};
1242#endif
1243
1244struct sched_entity {
1245        struct load_weight      load;           /* for load-balancing */
1246        struct rb_node          run_node;
1247        struct list_head        group_node;
1248        unsigned int            on_rq;
1249
1250        u64                     exec_start;
1251        u64                     sum_exec_runtime;
1252        u64                     vruntime;
1253        u64                     prev_sum_exec_runtime;
1254
1255        u64                     nr_migrations;
1256
1257#ifdef CONFIG_SCHEDSTATS
1258        struct sched_statistics statistics;
1259#endif
1260
1261#ifdef CONFIG_FAIR_GROUP_SCHED
1262        int                     depth;
1263        struct sched_entity     *parent;
1264        /* rq on which this entity is (to be) queued: */
1265        struct cfs_rq           *cfs_rq;
1266        /* rq "owned" by this entity/group: */
1267        struct cfs_rq           *my_q;
1268#endif
1269
1270#ifdef CONFIG_SMP
1271        /* Per entity load average tracking */
1272        struct sched_avg        avg;
1273#endif
1274};
1275
1276struct sched_rt_entity {
1277        struct list_head run_list;
1278        unsigned long timeout;
1279        unsigned long watchdog_stamp;
1280        unsigned int time_slice;
1281
1282        struct sched_rt_entity *back;
1283#ifdef CONFIG_RT_GROUP_SCHED
1284        struct sched_rt_entity  *parent;
1285        /* rq on which this entity is (to be) queued: */
1286        struct rt_rq            *rt_rq;
1287        /* rq "owned" by this entity/group: */
1288        struct rt_rq            *my_q;
1289#endif
1290};
1291
1292struct sched_dl_entity {
1293        struct rb_node  rb_node;
1294
1295        /*
1296         * Original scheduling parameters. Copied here from sched_attr
1297         * during sched_setattr(), they will remain the same until
1298         * the next sched_setattr().
1299         */
1300        u64 dl_runtime;         /* maximum runtime for each instance    */
1301        u64 dl_deadline;        /* relative deadline of each instance   */
1302        u64 dl_period;          /* separation of two instances (period) */
1303        u64 dl_bw;              /* dl_runtime / dl_deadline             */
1304
1305        /*
1306         * Actual scheduling parameters. Initialized with the values above,
1307         * they are continously updated during task execution. Note that
1308         * the remaining runtime could be < 0 in case we are in overrun.
1309         */
1310        s64 runtime;            /* remaining runtime for this instance  */
1311        u64 deadline;           /* absolute deadline for this instance  */
1312        unsigned int flags;     /* specifying the scheduler behaviour   */
1313
1314        /*
1315         * Some bool flags:
1316         *
1317         * @dl_throttled tells if we exhausted the runtime. If so, the
1318         * task has to wait for a replenishment to be performed at the
1319         * next firing of dl_timer.
1320         *
1321         * @dl_new tells if a new instance arrived. If so we must
1322         * start executing it with full runtime and reset its absolute
1323         * deadline;
1324         *
1325         * @dl_boosted tells if we are boosted due to DI. If so we are
1326         * outside bandwidth enforcement mechanism (but only until we
1327         * exit the critical section);
1328         *
1329         * @dl_yielded tells if task gave up the cpu before consuming
1330         * all its available runtime during the last job.
1331         */
1332        int dl_throttled, dl_new, dl_boosted, dl_yielded;
1333
1334        /*
1335         * Bandwidth enforcement timer. Each -deadline task has its
1336         * own bandwidth to be enforced, thus we need one timer per task.
1337         */
1338        struct hrtimer dl_timer;
1339};
1340
1341union rcu_special {
1342        struct {
1343                u8 blocked;
1344                u8 need_qs;
1345                u8 exp_need_qs;
1346                u8 pad; /* Otherwise the compiler can store garbage here. */
1347        } b; /* Bits. */
1348        u32 s; /* Set of bits. */
1349};
1350struct rcu_node;
1351
1352enum perf_event_task_context {
1353        perf_invalid_context = -1,
1354        perf_hw_context = 0,
1355        perf_sw_context,
1356        perf_nr_task_contexts,
1357};
1358
1359/* Track pages that require TLB flushes */
1360struct tlbflush_unmap_batch {
1361        /*
1362         * Each bit set is a CPU that potentially has a TLB entry for one of
1363         * the PFNs being flushed. See set_tlb_ubc_flush_pending().
1364         */
1365        struct cpumask cpumask;
1366
1367        /* True if any bit in cpumask is set */
1368        bool flush_required;
1369
1370        /*
1371         * If true then the PTE was dirty when unmapped. The entry must be
1372         * flushed before IO is initiated or a stale TLB entry potentially
1373         * allows an update without redirtying the page.
1374         */
1375        bool writable;
1376};
1377
1378struct task_struct {
1379        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
1380        void *stack;
1381        atomic_t usage;
1382        unsigned int flags;     /* per process flags, defined below */
1383        unsigned int ptrace;
1384
1385#ifdef CONFIG_SMP
1386        struct llist_node wake_entry;
1387        int on_cpu;
1388        unsigned int wakee_flips;
1389        unsigned long wakee_flip_decay_ts;
1390        struct task_struct *last_wakee;
1391
1392        int wake_cpu;
1393#endif
1394        int on_rq;
1395
1396        int prio, static_prio, normal_prio;
1397        unsigned int rt_priority;
1398        const struct sched_class *sched_class;
1399        struct sched_entity se;
1400        struct sched_rt_entity rt;
1401#ifdef CONFIG_CGROUP_SCHED
1402        struct task_group *sched_task_group;
1403#endif
1404        struct sched_dl_entity dl;
1405
1406#ifdef CONFIG_PREEMPT_NOTIFIERS
1407        /* list of struct preempt_notifier: */
1408        struct hlist_head preempt_notifiers;
1409#endif
1410
1411#ifdef CONFIG_BLK_DEV_IO_TRACE
1412        unsigned int btrace_seq;
1413#endif
1414
1415        unsigned int policy;
1416        int nr_cpus_allowed;
1417        cpumask_t cpus_allowed;
1418
1419#ifdef CONFIG_PREEMPT_RCU
1420        int rcu_read_lock_nesting;
1421        union rcu_special rcu_read_unlock_special;
1422        struct list_head rcu_node_entry;
1423        struct rcu_node *rcu_blocked_node;
1424#endif /* #ifdef CONFIG_PREEMPT_RCU */
1425#ifdef CONFIG_TASKS_RCU
1426        unsigned long rcu_tasks_nvcsw;
1427        bool rcu_tasks_holdout;
1428        struct list_head rcu_tasks_holdout_list;
1429        int rcu_tasks_idle_cpu;
1430#endif /* #ifdef CONFIG_TASKS_RCU */
1431
1432#ifdef CONFIG_SCHED_INFO
1433        struct sched_info sched_info;
1434#endif
1435
1436        struct list_head tasks;
1437#ifdef CONFIG_SMP
1438        struct plist_node pushable_tasks;
1439        struct rb_node pushable_dl_tasks;
1440#endif
1441
1442        struct mm_struct *mm, *active_mm;
1443        /* per-thread vma caching */
1444        u32 vmacache_seqnum;
1445        struct vm_area_struct *vmacache[VMACACHE_SIZE];
1446#if defined(SPLIT_RSS_COUNTING)
1447        struct task_rss_stat    rss_stat;
1448#endif
1449/* task state */
1450        int exit_state;
1451        int exit_code, exit_signal;
1452        int pdeath_signal;  /*  The signal sent when the parent dies  */
1453        unsigned long jobctl;   /* JOBCTL_*, siglock protected */
1454
1455        /* Used for emulating ABI behavior of previous Linux versions */
1456        unsigned int personality;
1457
1458        /* scheduler bits, serialized by scheduler locks */
1459        unsigned sched_reset_on_fork:1;
1460        unsigned sched_contributes_to_load:1;
1461        unsigned sched_migrated:1;
1462        unsigned :0; /* force alignment to the next boundary */
1463
1464        /* unserialized, strictly 'current' */
1465        unsigned in_execve:1; /* bit to tell LSMs we're in execve */
1466        unsigned in_iowait:1;
1467#ifdef CONFIG_MEMCG
1468        unsigned memcg_may_oom:1;
1469#endif
1470#ifdef CONFIG_MEMCG_KMEM
1471        unsigned memcg_kmem_skip_account:1;
1472#endif
1473#ifdef CONFIG_COMPAT_BRK
1474        unsigned brk_randomized:1;
1475#endif
1476
1477        unsigned long atomic_flags; /* Flags needing atomic access. */
1478
1479        struct restart_block restart_block;
1480
1481        pid_t pid;
1482        pid_t tgid;
1483
1484#ifdef CONFIG_CC_STACKPROTECTOR
1485        /* Canary value for the -fstack-protector gcc feature */
1486        unsigned long stack_canary;
1487#endif
1488        /*
1489         * pointers to (original) parent process, youngest child, younger sibling,
1490         * older sibling, respectively.  (p->father can be replaced with
1491         * p->real_parent->pid)
1492         */
1493        struct task_struct __rcu *real_parent; /* real parent process */
1494        struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1495        /*
1496         * children/sibling forms the list of my natural children
1497         */
1498        struct list_head children;      /* list of my children */
1499        struct list_head sibling;       /* linkage in my parent's children list */
1500        struct task_struct *group_leader;       /* threadgroup leader */
1501
1502        /*
1503         * ptraced is the list of tasks this task is using ptrace on.
1504         * This includes both natural children and PTRACE_ATTACH targets.
1505         * p->ptrace_entry is p's link on the p->parent->ptraced list.
1506         */
1507        struct list_head ptraced;
1508        struct list_head ptrace_entry;
1509
1510        /* PID/PID hash table linkage. */
1511        struct pid_link pids[PIDTYPE_MAX];
1512        struct list_head thread_group;
1513        struct list_head thread_node;
1514
1515        struct completion *vfork_done;          /* for vfork() */
1516        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
1517        int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
1518
1519        cputime_t utime, stime, utimescaled, stimescaled;
1520        cputime_t gtime;
1521        struct prev_cputime prev_cputime;
1522#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1523        seqlock_t vtime_seqlock;
1524        unsigned long long vtime_snap;
1525        enum {
1526                VTIME_SLEEPING = 0,
1527                VTIME_USER,
1528                VTIME_SYS,
1529        } vtime_snap_whence;
1530#endif
1531        unsigned long nvcsw, nivcsw; /* context switch counts */
1532        u64 start_time;         /* monotonic time in nsec */
1533        u64 real_start_time;    /* boot based time in nsec */
1534/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1535        unsigned long min_flt, maj_flt;
1536
1537        struct task_cputime cputime_expires;
1538        struct list_head cpu_timers[3];
1539
1540/* process credentials */
1541        const struct cred __rcu *real_cred; /* objective and real subjective task
1542                                         * credentials (COW) */
1543        const struct cred __rcu *cred;  /* effective (overridable) subjective task
1544                                         * credentials (COW) */
1545        char comm[TASK_COMM_LEN]; /* executable name excluding path
1546                                     - access with [gs]et_task_comm (which lock
1547                                       it with task_lock())
1548                                     - initialized normally by setup_new_exec */
1549/* file system info */
1550        struct nameidata *nameidata;
1551#ifdef CONFIG_SYSVIPC
1552/* ipc stuff */
1553        struct sysv_sem sysvsem;
1554        struct sysv_shm sysvshm;
1555#endif
1556#ifdef CONFIG_DETECT_HUNG_TASK
1557/* hung task detection */
1558        unsigned long last_switch_count;
1559#endif
1560/* filesystem information */
1561        struct fs_struct *fs;
1562/* open file information */
1563        struct files_struct *files;
1564/* namespaces */
1565        struct nsproxy *nsproxy;
1566/* signal handlers */
1567        struct signal_struct *signal;
1568        struct sighand_struct *sighand;
1569
1570        sigset_t blocked, real_blocked;
1571        sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1572        struct sigpending pending;
1573
1574        unsigned long sas_ss_sp;
1575        size_t sas_ss_size;
1576
1577        struct callback_head *task_works;
1578
1579        struct audit_context *audit_context;
1580#ifdef CONFIG_AUDITSYSCALL
1581        kuid_t loginuid;
1582        unsigned int sessionid;
1583#endif
1584        struct seccomp seccomp;
1585
1586/* Thread group tracking */
1587        u32 parent_exec_id;
1588        u32 self_exec_id;
1589/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1590 * mempolicy */
1591        spinlock_t alloc_lock;
1592
1593        /* Protection of the PI data structures: */
1594        raw_spinlock_t pi_lock;
1595
1596        struct wake_q_node wake_q;
1597
1598#ifdef CONFIG_RT_MUTEXES
1599        /* PI waiters blocked on a rt_mutex held by this task */
1600        struct rb_root pi_waiters;
1601        struct rb_node *pi_waiters_leftmost;
1602        /* Deadlock detection and priority inheritance handling */
1603        struct rt_mutex_waiter *pi_blocked_on;
1604#endif
1605
1606#ifdef CONFIG_DEBUG_MUTEXES
1607        /* mutex deadlock detection */
1608        struct mutex_waiter *blocked_on;
1609#endif
1610#ifdef CONFIG_TRACE_IRQFLAGS
1611        unsigned int irq_events;
1612        unsigned long hardirq_enable_ip;
1613        unsigned long hardirq_disable_ip;
1614        unsigned int hardirq_enable_event;
1615        unsigned int hardirq_disable_event;
1616        int hardirqs_enabled;
1617        int hardirq_context;
1618        unsigned long softirq_disable_ip;
1619        unsigned long softirq_enable_ip;
1620        unsigned int softirq_disable_event;
1621        unsigned int softirq_enable_event;
1622        int softirqs_enabled;
1623        int softirq_context;
1624#endif
1625#ifdef CONFIG_LOCKDEP
1626# define MAX_LOCK_DEPTH 48UL
1627        u64 curr_chain_key;
1628        int lockdep_depth;
1629        unsigned int lockdep_recursion;
1630        struct held_lock held_locks[MAX_LOCK_DEPTH];
1631        gfp_t lockdep_reclaim_gfp;
1632#endif
1633
1634/* journalling filesystem info */
1635        void *journal_info;
1636
1637/* stacked block device info */
1638        struct bio_list *bio_list;
1639
1640#ifdef CONFIG_BLOCK
1641/* stack plugging */
1642        struct blk_plug *plug;
1643#endif
1644
1645/* VM state */
1646        struct reclaim_state *reclaim_state;
1647
1648        struct backing_dev_info *backing_dev_info;
1649
1650        struct io_context *io_context;
1651
1652        unsigned long ptrace_message;
1653        siginfo_t *last_siginfo; /* For ptrace use.  */
1654        struct task_io_accounting ioac;
1655#if defined(CONFIG_TASK_XACCT)
1656        u64 acct_rss_mem1;      /* accumulated rss usage */
1657        u64 acct_vm_mem1;       /* accumulated virtual memory usage */
1658        cputime_t acct_timexpd; /* stime + utime since last update */
1659#endif
1660#ifdef CONFIG_CPUSETS
1661        nodemask_t mems_allowed;        /* Protected by alloc_lock */
1662        seqcount_t mems_allowed_seq;    /* Seqence no to catch updates */
1663        int cpuset_mem_spread_rotor;
1664        int cpuset_slab_spread_rotor;
1665#endif
1666#ifdef CONFIG_CGROUPS
1667        /* Control Group info protected by css_set_lock */
1668        struct css_set __rcu *cgroups;
1669        /* cg_list protected by css_set_lock and tsk->alloc_lock */
1670        struct list_head cg_list;
1671#endif
1672#ifdef CONFIG_FUTEX
1673        struct robust_list_head __user *robust_list;
1674#ifdef CONFIG_COMPAT
1675        struct compat_robust_list_head __user *compat_robust_list;
1676#endif
1677        struct list_head pi_state_list;
1678        struct futex_pi_state *pi_state_cache;
1679#endif
1680#ifdef CONFIG_PERF_EVENTS
1681        struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1682        struct mutex perf_event_mutex;
1683        struct list_head perf_event_list;
1684#endif
1685#ifdef CONFIG_DEBUG_PREEMPT
1686        unsigned long preempt_disable_ip;
1687#endif
1688#ifdef CONFIG_NUMA
1689        struct mempolicy *mempolicy;    /* Protected by alloc_lock */
1690        short il_next;
1691        short pref_node_fork;
1692#endif
1693#ifdef CONFIG_NUMA_BALANCING
1694        int numa_scan_seq;
1695        unsigned int numa_scan_period;
1696        unsigned int numa_scan_period_max;
1697        int numa_preferred_nid;
1698        unsigned long numa_migrate_retry;
1699        u64 node_stamp;                 /* migration stamp  */
1700        u64 last_task_numa_placement;
1701        u64 last_sum_exec_runtime;
1702        struct callback_head numa_work;
1703
1704        struct list_head numa_entry;
1705        struct numa_group *numa_group;
1706
1707        /*
1708         * numa_faults is an array split into four regions:
1709         * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1710         * in this precise order.
1711         *
1712         * faults_memory: Exponential decaying average of faults on a per-node
1713         * basis. Scheduling placement decisions are made based on these
1714         * counts. The values remain static for the duration of a PTE scan.
1715         * faults_cpu: Track the nodes the process was running on when a NUMA
1716         * hinting fault was incurred.
1717         * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1718         * during the current scan window. When the scan completes, the counts
1719         * in faults_memory and faults_cpu decay and these values are copied.
1720         */
1721        unsigned long *numa_faults;
1722        unsigned long total_numa_faults;
1723
1724        /*
1725         * numa_faults_locality tracks if faults recorded during the last
1726         * scan window were remote/local or failed to migrate. The task scan
1727         * period is adapted based on the locality of the faults with different
1728         * weights depending on whether they were shared or private faults
1729         */
1730        unsigned long numa_faults_locality[3];
1731
1732        unsigned long numa_pages_migrated;
1733#endif /* CONFIG_NUMA_BALANCING */
1734
1735#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
1736        struct tlbflush_unmap_batch tlb_ubc;
1737#endif
1738
1739        struct rcu_head rcu;
1740
1741        /*
1742         * cache last used pipe for splice
1743         */
1744        struct pipe_inode_info *splice_pipe;
1745
1746        struct page_frag task_frag;
1747
1748#ifdef  CONFIG_TASK_DELAY_ACCT
1749        struct task_delay_info *delays;
1750#endif
1751#ifdef CONFIG_FAULT_INJECTION
1752        int make_it_fail;
1753#endif
1754        /*
1755         * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1756         * balance_dirty_pages() for some dirty throttling pause
1757         */
1758        int nr_dirtied;
1759        int nr_dirtied_pause;
1760        unsigned long dirty_paused_when; /* start of a write-and-pause period */
1761
1762#ifdef CONFIG_LATENCYTOP
1763        int latency_record_count;
1764        struct latency_record latency_record[LT_SAVECOUNT];
1765#endif
1766        /*
1767         * time slack values; these are used to round up poll() and
1768         * select() etc timeout values. These are in nanoseconds.
1769         */
1770        unsigned long timer_slack_ns;
1771        unsigned long default_timer_slack_ns;
1772
1773#ifdef CONFIG_KASAN
1774        unsigned int kasan_depth;
1775#endif
1776#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1777        /* Index of current stored address in ret_stack */
1778        int curr_ret_stack;
1779        /* Stack of return addresses for return function tracing */
1780        struct ftrace_ret_stack *ret_stack;
1781        /* time stamp for last schedule */
1782        unsigned long long ftrace_timestamp;
1783        /*
1784         * Number of functions that haven't been traced
1785         * because of depth overrun.
1786         */
1787        atomic_t trace_overrun;
1788        /* Pause for the tracing */
1789        atomic_t tracing_graph_pause;
1790#endif
1791#ifdef CONFIG_TRACING
1792        /* state flags for use by tracers */
1793        unsigned long trace;
1794        /* bitmask and counter of trace recursion */
1795        unsigned long trace_recursion;
1796#endif /* CONFIG_TRACING */
1797#ifdef CONFIG_MEMCG
1798        struct mem_cgroup *memcg_in_oom;
1799        gfp_t memcg_oom_gfp_mask;
1800        int memcg_oom_order;
1801
1802        /* number of pages to reclaim on returning to userland */
1803        unsigned int memcg_nr_pages_over_high;
1804#endif
1805#ifdef CONFIG_UPROBES
1806        struct uprobe_task *utask;
1807#endif
1808#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1809        unsigned int    sequential_io;
1810        unsigned int    sequential_io_avg;
1811#endif
1812#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1813        unsigned long   task_state_change;
1814#endif
1815        int pagefault_disabled;
1816/* CPU-specific state of this task */
1817        struct thread_struct thread;
1818/*
1819 * WARNING: on x86, 'thread_struct' contains a variable-sized
1820 * structure.  It *MUST* be at the end of 'task_struct'.
1821 *
1822 * Do not put anything below here!
1823 */
1824};
1825
1826#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
1827extern int arch_task_struct_size __read_mostly;
1828#else
1829# define arch_task_struct_size (sizeof(struct task_struct))
1830#endif
1831
1832/* Future-safe accessor for struct task_struct's cpus_allowed. */
1833#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1834
1835#define TNF_MIGRATED    0x01
1836#define TNF_NO_GROUP    0x02
1837#define TNF_SHARED      0x04
1838#define TNF_FAULT_LOCAL 0x08
1839#define TNF_MIGRATE_FAIL 0x10
1840
1841#ifdef CONFIG_NUMA_BALANCING
1842extern void task_numa_fault(int last_node, int node, int pages, int flags);
1843extern pid_t task_numa_group_id(struct task_struct *p);
1844extern void set_numabalancing_state(bool enabled);
1845extern void task_numa_free(struct task_struct *p);
1846extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1847                                        int src_nid, int dst_cpu);
1848#else
1849static inline void task_numa_fault(int last_node, int node, int pages,
1850                                   int flags)
1851{
1852}
1853static inline pid_t task_numa_group_id(struct task_struct *p)
1854{
1855        return 0;
1856}
1857static inline void set_numabalancing_state(bool enabled)
1858{
1859}
1860static inline void task_numa_free(struct task_struct *p)
1861{
1862}
1863static inline bool should_numa_migrate_memory(struct task_struct *p,
1864                                struct page *page, int src_nid, int dst_cpu)
1865{
1866        return true;
1867}
1868#endif
1869
1870static inline struct pid *task_pid(struct task_struct *task)
1871{
1872        return task->pids[PIDTYPE_PID].pid;
1873}
1874
1875static inline struct pid *task_tgid(struct task_struct *task)
1876{
1877        return task->group_leader->pids[PIDTYPE_PID].pid;
1878}
1879
1880/*
1881 * Without tasklist or rcu lock it is not safe to dereference
1882 * the result of task_pgrp/task_session even if task == current,
1883 * we can race with another thread doing sys_setsid/sys_setpgid.
1884 */
1885static inline struct pid *task_pgrp(struct task_struct *task)
1886{
1887        return task->group_leader->pids[PIDTYPE_PGID].pid;
1888}
1889
1890static inline struct pid *task_session(struct task_struct *task)
1891{
1892        return task->group_leader->pids[PIDTYPE_SID].pid;
1893}
1894
1895struct pid_namespace;
1896
1897/*
1898 * the helpers to get the task's different pids as they are seen
1899 * from various namespaces
1900 *
1901 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1902 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1903 *                     current.
1904 * task_xid_nr_ns()  : id seen from the ns specified;
1905 *
1906 * set_task_vxid()   : assigns a virtual id to a task;
1907 *
1908 * see also pid_nr() etc in include/linux/pid.h
1909 */
1910pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1911                        struct pid_namespace *ns);
1912
1913static inline pid_t task_pid_nr(struct task_struct *tsk)
1914{
1915        return tsk->pid;
1916}
1917
1918static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1919                                        struct pid_namespace *ns)
1920{
1921        return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1922}
1923
1924static inline pid_t task_pid_vnr(struct task_struct *tsk)
1925{
1926        return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1927}
1928
1929
1930static inline pid_t task_tgid_nr(struct task_struct *tsk)
1931{
1932        return tsk->tgid;
1933}
1934
1935pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1936
1937static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1938{
1939        return pid_vnr(task_tgid(tsk));
1940}
1941
1942
1943static inline int pid_alive(const struct task_struct *p);
1944static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1945{
1946        pid_t pid = 0;
1947
1948        rcu_read_lock();
1949        if (pid_alive(tsk))
1950                pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1951        rcu_read_unlock();
1952
1953        return pid;
1954}
1955
1956static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1957{
1958        return task_ppid_nr_ns(tsk, &init_pid_ns);
1959}
1960
1961static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1962                                        struct pid_namespace *ns)
1963{
1964        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1965}
1966
1967static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1968{
1969        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1970}
1971
1972
1973static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1974                                        struct pid_namespace *ns)
1975{
1976        return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1977}
1978
1979static inline pid_t task_session_vnr(struct task_struct *tsk)
1980{
1981        return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1982}
1983
1984/* obsolete, do not use */
1985static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1986{
1987        return task_pgrp_nr_ns(tsk, &init_pid_ns);
1988}
1989
1990/**
1991 * pid_alive - check that a task structure is not stale
1992 * @p: Task structure to be checked.
1993 *
1994 * Test if a process is not yet dead (at most zombie state)
1995 * If pid_alive fails, then pointers within the task structure
1996 * can be stale and must not be dereferenced.
1997 *
1998 * Return: 1 if the process is alive. 0 otherwise.
1999 */
2000static inline int pid_alive(const struct task_struct *p)
2001{
2002        return p->pids[PIDTYPE_PID].pid != NULL;
2003}
2004
2005/**
2006 * is_global_init - check if a task structure is init. Since init
2007 * is free to have sub-threads we need to check tgid.
2008 * @tsk: Task structure to be checked.
2009 *
2010 * Check if a task structure is the first user space task the kernel created.
2011 *
2012 * Return: 1 if the task structure is init. 0 otherwise.
2013 */
2014static inline int is_global_init(struct task_struct *tsk)
2015{
2016        return task_tgid_nr(tsk) == 1;
2017}
2018
2019extern struct pid *cad_pid;
2020
2021extern void free_task(struct task_struct *tsk);
2022#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
2023
2024extern void __put_task_struct(struct task_struct *t);
2025
2026static inline void put_task_struct(struct task_struct *t)
2027{
2028        if (atomic_dec_and_test(&t->usage))
2029                __put_task_struct(t);
2030}
2031
2032#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
2033extern void task_cputime(struct task_struct *t,
2034                         cputime_t *utime, cputime_t *stime);
2035extern void task_cputime_scaled(struct task_struct *t,
2036                                cputime_t *utimescaled, cputime_t *stimescaled);
2037extern cputime_t task_gtime(struct task_struct *t);
2038#else
2039static inline void task_cputime(struct task_struct *t,
2040                                cputime_t *utime, cputime_t *stime)
2041{
2042        if (utime)
2043                *utime = t->utime;
2044        if (stime)
2045                *stime = t->stime;
2046}
2047
2048static inline void task_cputime_scaled(struct task_struct *t,
2049                                       cputime_t *utimescaled,
2050                                       cputime_t *stimescaled)
2051{
2052        if (utimescaled)
2053                *utimescaled = t->utimescaled;
2054        if (stimescaled)
2055                *stimescaled = t->stimescaled;
2056}
2057
2058static inline cputime_t task_gtime(struct task_struct *t)
2059{
2060        return t->gtime;
2061}
2062#endif
2063extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2064extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2065
2066/*
2067 * Per process flags
2068 */
2069#define PF_EXITING      0x00000004      /* getting shut down */
2070#define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
2071#define PF_VCPU         0x00000010      /* I'm a virtual CPU */
2072#define PF_WQ_WORKER    0x00000020      /* I'm a workqueue worker */
2073#define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
2074#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
2075#define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
2076#define PF_DUMPCORE     0x00000200      /* dumped core */
2077#define PF_SIGNALED     0x00000400      /* killed by a signal */
2078#define PF_MEMALLOC     0x00000800      /* Allocating memory */
2079#define PF_NPROC_EXCEEDED 0x00001000    /* set_user noticed that RLIMIT_NPROC was exceeded */
2080#define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
2081#define PF_USED_ASYNC   0x00004000      /* used async_schedule*(), used by module init */
2082#define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
2083#define PF_FROZEN       0x00010000      /* frozen for system suspend */
2084#define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
2085#define PF_KSWAPD       0x00040000      /* I am kswapd */
2086#define PF_MEMALLOC_NOIO 0x00080000     /* Allocating memory without IO involved */
2087#define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
2088#define PF_KTHREAD      0x00200000      /* I am a kernel thread */
2089#define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
2090#define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
2091#define PF_NO_SETAFFINITY 0x04000000    /* Userland is not allowed to meddle with cpus_allowed */
2092#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
2093#define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
2094#define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezable */
2095#define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
2096
2097/*
2098 * Only the _current_ task can read/write to tsk->flags, but other
2099 * tasks can access tsk->flags in readonly mode for example
2100 * with tsk_used_math (like during threaded core dumping).
2101 * There is however an exception to this rule during ptrace
2102 * or during fork: the ptracer task is allowed to write to the
2103 * child->flags of its traced child (same goes for fork, the parent
2104 * can write to the child->flags), because we're guaranteed the
2105 * child is not running and in turn not changing child->flags
2106 * at the same time the parent does it.
2107 */
2108#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
2109#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
2110#define clear_used_math() clear_stopped_child_used_math(current)
2111#define set_used_math() set_stopped_child_used_math(current)
2112#define conditional_stopped_child_used_math(condition, child) \
2113        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
2114#define conditional_used_math(condition) \
2115        conditional_stopped_child_used_math(condition, current)
2116#define copy_to_stopped_child_used_math(child) \
2117        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
2118/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
2119#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
2120#define used_math() tsk_used_math(current)
2121
2122/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
2123 * __GFP_FS is also cleared as it implies __GFP_IO.
2124 */
2125static inline gfp_t memalloc_noio_flags(gfp_t flags)
2126{
2127        if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2128                flags &= ~(__GFP_IO | __GFP_FS);
2129        return flags;
2130}
2131
2132static inline unsigned int memalloc_noio_save(void)
2133{
2134        unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
2135        current->flags |= PF_MEMALLOC_NOIO;
2136        return flags;
2137}
2138
2139static inline void memalloc_noio_restore(unsigned int flags)
2140{
2141        current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
2142}
2143
2144/* Per-process atomic flags. */
2145#define PFA_NO_NEW_PRIVS 0      /* May not gain new privileges. */
2146#define PFA_SPREAD_PAGE  1      /* Spread page cache over cpuset */
2147#define PFA_SPREAD_SLAB  2      /* Spread some slab caches over cpuset */
2148
2149
2150#define TASK_PFA_TEST(name, func)                                       \
2151        static inline bool task_##func(struct task_struct *p)           \
2152        { return test_bit(PFA_##name, &p->atomic_flags); }
2153#define TASK_PFA_SET(name, func)                                        \
2154        static inline void task_set_##func(struct task_struct *p)       \
2155        { set_bit(PFA_##name, &p->atomic_flags); }
2156#define TASK_PFA_CLEAR(name, func)                                      \
2157        static inline void task_clear_##func(struct task_struct *p)     \
2158        { clear_bit(PFA_##name, &p->atomic_flags); }
2159
2160TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
2161TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2162
2163TASK_PFA_TEST(SPREAD_PAGE, spread_page)
2164TASK_PFA_SET(SPREAD_PAGE, spread_page)
2165TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2166
2167TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2168TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2169TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2170
2171/*
2172 * task->jobctl flags
2173 */
2174#define JOBCTL_STOP_SIGMASK     0xffff  /* signr of the last group stop */
2175
2176#define JOBCTL_STOP_DEQUEUED_BIT 16     /* stop signal dequeued */
2177#define JOBCTL_STOP_PENDING_BIT 17      /* task should stop for group stop */
2178#define JOBCTL_STOP_CONSUME_BIT 18      /* consume group stop count */
2179#define JOBCTL_TRAP_STOP_BIT    19      /* trap for STOP */
2180#define JOBCTL_TRAP_NOTIFY_BIT  20      /* trap for NOTIFY */
2181#define JOBCTL_TRAPPING_BIT     21      /* switching to TRACED */
2182#define JOBCTL_LISTENING_BIT    22      /* ptracer is listening for events */
2183
2184#define JOBCTL_STOP_DEQUEUED    (1UL << JOBCTL_STOP_DEQUEUED_BIT)
2185#define JOBCTL_STOP_PENDING     (1UL << JOBCTL_STOP_PENDING_BIT)
2186#define JOBCTL_STOP_CONSUME     (1UL << JOBCTL_STOP_CONSUME_BIT)
2187#define JOBCTL_TRAP_STOP        (1UL << JOBCTL_TRAP_STOP_BIT)
2188#define JOBCTL_TRAP_NOTIFY      (1UL << JOBCTL_TRAP_NOTIFY_BIT)
2189#define JOBCTL_TRAPPING         (1UL << JOBCTL_TRAPPING_BIT)
2190#define JOBCTL_LISTENING        (1UL << JOBCTL_LISTENING_BIT)
2191
2192#define JOBCTL_TRAP_MASK        (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2193#define JOBCTL_PENDING_MASK     (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2194
2195extern bool task_set_jobctl_pending(struct task_struct *task,
2196                                    unsigned long mask);
2197extern void task_clear_jobctl_trapping(struct task_struct *task);
2198extern void task_clear_jobctl_pending(struct task_struct *task,
2199                                      unsigned long mask);
2200
2201static inline void rcu_copy_process(struct task_struct *p)
2202{
2203#ifdef CONFIG_PREEMPT_RCU
2204        p->rcu_read_lock_nesting = 0;
2205        p->rcu_read_unlock_special.s = 0;
2206        p->rcu_blocked_node = NULL;
2207        INIT_LIST_HEAD(&p->rcu_node_entry);
2208#endif /* #ifdef CONFIG_PREEMPT_RCU */
2209#ifdef CONFIG_TASKS_RCU
2210        p->rcu_tasks_holdout = false;
2211        INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2212        p->rcu_tasks_idle_cpu = -1;
2213#endif /* #ifdef CONFIG_TASKS_RCU */
2214}
2215
2216static inline void tsk_restore_flags(struct task_struct *task,
2217                                unsigned long orig_flags, unsigned long flags)
2218{
2219        task->flags &= ~flags;
2220        task->flags |= orig_flags & flags;
2221}
2222
2223extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2224                                     const struct cpumask *trial);
2225extern int task_can_attach(struct task_struct *p,
2226                           const struct cpumask *cs_cpus_allowed);
2227#ifdef CONFIG_SMP
2228extern void do_set_cpus_allowed(struct task_struct *p,
2229                               const struct cpumask *new_mask);
2230
2231extern int set_cpus_allowed_ptr(struct task_struct *p,
2232                                const struct cpumask *new_mask);
2233#else
2234static inline void do_set_cpus_allowed(struct task_struct *p,
2235                                      const struct cpumask *new_mask)
2236{
2237}
2238static inline int set_cpus_allowed_ptr(struct task_struct *p,
2239                                       const struct cpumask *new_mask)
2240{
2241        if (!cpumask_test_cpu(0, new_mask))
2242                return -EINVAL;
2243        return 0;
2244}
2245#endif
2246
2247#ifdef CONFIG_NO_HZ_COMMON
2248void calc_load_enter_idle(void);
2249void calc_load_exit_idle(void);
2250#else
2251static inline void calc_load_enter_idle(void) { }
2252static inline void calc_load_exit_idle(void) { }
2253#endif /* CONFIG_NO_HZ_COMMON */
2254
2255/*
2256 * Do not use outside of architecture code which knows its limitations.
2257 *
2258 * sched_clock() has no promise of monotonicity or bounded drift between
2259 * CPUs, use (which you should not) requires disabling IRQs.
2260 *
2261 * Please use one of the three interfaces below.
2262 */
2263extern unsigned long long notrace sched_clock(void);
2264/*
2265 * See the comment in kernel/sched/clock.c
2266 */
2267extern u64 cpu_clock(int cpu);
2268extern u64 local_clock(void);
2269extern u64 running_clock(void);
2270extern u64 sched_clock_cpu(int cpu);
2271
2272
2273extern void sched_clock_init(void);
2274
2275#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2276static inline void sched_clock_tick(void)
2277{
2278}
2279
2280static inline void sched_clock_idle_sleep_event(void)
2281{
2282}
2283
2284static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2285{
2286}
2287#else
2288/*
2289 * Architectures can set this to 1 if they have specified
2290 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2291 * but then during bootup it turns out that sched_clock()
2292 * is reliable after all:
2293 */
2294extern int sched_clock_stable(void);
2295extern void set_sched_clock_stable(void);
2296extern void clear_sched_clock_stable(void);
2297
2298extern void sched_clock_tick(void);
2299extern void sched_clock_idle_sleep_event(void);
2300extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2301#endif
2302
2303#ifdef CONFIG_IRQ_TIME_ACCOUNTING
2304/*
2305 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2306 * The reason for this explicit opt-in is not to have perf penalty with
2307 * slow sched_clocks.
2308 */
2309extern void enable_sched_clock_irqtime(void);
2310extern void disable_sched_clock_irqtime(void);
2311#else
2312static inline void enable_sched_clock_irqtime(void) {}
2313static inline void disable_sched_clock_irqtime(void) {}
2314#endif
2315
2316extern unsigned long long
2317task_sched_runtime(struct task_struct *task);
2318
2319/* sched_exec is called by processes performing an exec */
2320#ifdef CONFIG_SMP
2321extern void sched_exec(void);
2322#else
2323#define sched_exec()   {}
2324#endif
2325
2326extern void sched_clock_idle_sleep_event(void);
2327extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2328
2329#ifdef CONFIG_HOTPLUG_CPU
2330extern void idle_task_exit(void);
2331#else
2332static inline void idle_task_exit(void) {}
2333#endif
2334
2335#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2336extern void wake_up_nohz_cpu(int cpu);
2337#else
2338static inline void wake_up_nohz_cpu(int cpu) { }
2339#endif
2340
2341#ifdef CONFIG_NO_HZ_FULL
2342extern bool sched_can_stop_tick(void);
2343extern u64 scheduler_tick_max_deferment(void);
2344#else
2345static inline bool sched_can_stop_tick(void) { return false; }
2346#endif
2347
2348#ifdef CONFIG_SCHED_AUTOGROUP
2349extern void sched_autogroup_create_attach(struct task_struct *p);
2350extern void sched_autogroup_detach(struct task_struct *p);
2351extern void sched_autogroup_fork(struct signal_struct *sig);
2352extern void sched_autogroup_exit(struct signal_struct *sig);
2353#ifdef CONFIG_PROC_FS
2354extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2355extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2356#endif
2357#else
2358static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2359static inline void sched_autogroup_detach(struct task_struct *p) { }
2360static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2361static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2362#endif
2363
2364extern int yield_to(struct task_struct *p, bool preempt);
2365extern void set_user_nice(struct task_struct *p, long nice);
2366extern int task_prio(const struct task_struct *p);
2367/**
2368 * task_nice - return the nice value of a given task.
2369 * @p: the task in question.
2370 *
2371 * Return: The nice value [ -20 ... 0 ... 19 ].
2372 */
2373static inline int task_nice(const struct task_struct *p)
2374{
2375        return PRIO_TO_NICE((p)->static_prio);
2376}
2377extern int can_nice(const struct task_struct *p, const int nice);
2378extern int task_curr(const struct task_struct *p);
2379extern int idle_cpu(int cpu);
2380extern int sched_setscheduler(struct task_struct *, int,
2381                              const struct sched_param *);
2382extern int sched_setscheduler_nocheck(struct task_struct *, int,
2383                                      const struct sched_param *);
2384extern int sched_setattr(struct task_struct *,
2385                         const struct sched_attr *);
2386extern struct task_struct *idle_task(int cpu);
2387/**
2388 * is_idle_task - is the specified task an idle task?
2389 * @p: the task in question.
2390 *
2391 * Return: 1 if @p is an idle task. 0 otherwise.
2392 */
2393static inline bool is_idle_task(const struct task_struct *p)
2394{
2395        return p->pid == 0;
2396}
2397extern struct task_struct *curr_task(int cpu);
2398extern void set_curr_task(int cpu, struct task_struct *p);
2399
2400void yield(void);
2401
2402union thread_union {
2403        struct thread_info thread_info;
2404        unsigned long stack[THREAD_SIZE/sizeof(long)];
2405};
2406
2407#ifndef __HAVE_ARCH_KSTACK_END
2408static inline int kstack_end(void *addr)
2409{
2410        /* Reliable end of stack detection:
2411         * Some APM bios versions misalign the stack
2412         */
2413        return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2414}
2415#endif
2416
2417extern union thread_union init_thread_union;
2418extern struct task_struct init_task;
2419
2420extern struct   mm_struct init_mm;
2421
2422extern struct pid_namespace init_pid_ns;
2423
2424/*
2425 * find a task by one of its numerical ids
2426 *
2427 * find_task_by_pid_ns():
2428 *      finds a task by its pid in the specified namespace
2429 * find_task_by_vpid():
2430 *      finds a task by its virtual pid
2431 *
2432 * see also find_vpid() etc in include/linux/pid.h
2433 */
2434
2435extern struct task_struct *find_task_by_vpid(pid_t nr);
2436extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2437                struct pid_namespace *ns);
2438
2439/* per-UID process charging. */
2440extern struct user_struct * alloc_uid(kuid_t);
2441static inline struct user_struct *get_uid(struct user_struct *u)
2442{
2443        atomic_inc(&u->__count);
2444        return u;
2445}
2446extern void free_uid(struct user_struct *);
2447
2448#include <asm/current.h>
2449
2450extern void xtime_update(unsigned long ticks);
2451
2452extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2453extern int wake_up_process(struct task_struct *tsk);
2454extern void wake_up_new_task(struct task_struct *tsk);
2455#ifdef CONFIG_SMP
2456 extern void kick_process(struct task_struct *tsk);
2457#else
2458 static inline void kick_process(struct task_struct *tsk) { }
2459#endif
2460extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2461extern void sched_dead(struct task_struct *p);
2462
2463extern void proc_caches_init(void);
2464extern void flush_signals(struct task_struct *);
2465extern void ignore_signals(struct task_struct *);
2466extern void flush_signal_handlers(struct task_struct *, int force_default);
2467extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2468
2469static inline int kernel_dequeue_signal(siginfo_t *info)
2470{
2471        struct task_struct *tsk = current;
2472        siginfo_t __info;
2473        int ret;
2474
2475        spin_lock_irq(&tsk->sighand->siglock);
2476        ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info);
2477        spin_unlock_irq(&tsk->sighand->siglock);
2478
2479        return ret;
2480}
2481
2482static inline void kernel_signal_stop(void)
2483{
2484        spin_lock_irq(&current->sighand->siglock);
2485        if (current->jobctl & JOBCTL_STOP_DEQUEUED)
2486                __set_current_state(TASK_STOPPED);
2487        spin_unlock_irq(&current->sighand->siglock);
2488
2489        schedule();
2490}
2491
2492extern void release_task(struct task_struct * p);
2493extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2494extern int force_sigsegv(int, struct task_struct *);
2495extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2496extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2497extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2498extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2499                                const struct cred *, u32);
2500extern int kill_pgrp(struct pid *pid, int sig, int priv);
2501extern int kill_pid(struct pid *pid, int sig, int priv);
2502extern int kill_proc_info(int, struct siginfo *, pid_t);
2503extern __must_check bool do_notify_parent(struct task_struct *, int);
2504extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2505extern void force_sig(int, struct task_struct *);
2506extern int send_sig(int, struct task_struct *, int);
2507extern int zap_other_threads(struct task_struct *p);
2508extern struct sigqueue *sigqueue_alloc(void);
2509extern void sigqueue_free(struct sigqueue *);
2510extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2511extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2512
2513static inline void restore_saved_sigmask(void)
2514{
2515        if (test_and_clear_restore_sigmask())
2516                __set_current_blocked(&current->saved_sigmask);
2517}
2518
2519static inline sigset_t *sigmask_to_save(void)
2520{
2521        sigset_t *res = &current->blocked;
2522        if (unlikely(test_restore_sigmask()))
2523                res = &current->saved_sigmask;
2524        return res;
2525}
2526
2527static inline int kill_cad_pid(int sig, int priv)
2528{
2529        return kill_pid(cad_pid, sig, priv);
2530}
2531
2532/* These can be the second arg to send_sig_info/send_group_sig_info.  */
2533#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2534#define SEND_SIG_PRIV   ((struct siginfo *) 1)
2535#define SEND_SIG_FORCED ((struct siginfo *) 2)
2536
2537/*
2538 * True if we are on the alternate signal stack.
2539 */
2540static inline int on_sig_stack(unsigned long sp)
2541{
2542#ifdef CONFIG_STACK_GROWSUP
2543        return sp >= current->sas_ss_sp &&
2544                sp - current->sas_ss_sp < current->sas_ss_size;
2545#else
2546        return sp > current->sas_ss_sp &&
2547                sp - current->sas_ss_sp <= current->sas_ss_size;
2548#endif
2549}
2550
2551static inline int sas_ss_flags(unsigned long sp)
2552{
2553        if (!current->sas_ss_size)
2554                return SS_DISABLE;
2555
2556        return on_sig_stack(sp) ? SS_ONSTACK : 0;
2557}
2558
2559static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2560{
2561        if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2562#ifdef CONFIG_STACK_GROWSUP
2563                return current->sas_ss_sp;
2564#else
2565                return current->sas_ss_sp + current->sas_ss_size;
2566#endif
2567        return sp;
2568}
2569
2570/*
2571 * Routines for handling mm_structs
2572 */
2573extern struct mm_struct * mm_alloc(void);
2574
2575/* mmdrop drops the mm and the page tables */
2576extern void __mmdrop(struct mm_struct *);
2577static inline void mmdrop(struct mm_struct * mm)
2578{
2579        if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2580                __mmdrop(mm);
2581}
2582
2583/* mmput gets rid of the mappings and all user-space */
2584extern void mmput(struct mm_struct *);
2585/* Grab a reference to a task's mm, if it is not already going away */
2586extern struct mm_struct *get_task_mm(struct task_struct *task);
2587/*
2588 * Grab a reference to a task's mm, if it is not already going away
2589 * and ptrace_may_access with the mode parameter passed to it
2590 * succeeds.
2591 */
2592extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2593/* Remove the current tasks stale references to the old mm_struct */
2594extern void mm_release(struct task_struct *, struct mm_struct *);
2595
2596#ifdef CONFIG_HAVE_COPY_THREAD_TLS
2597extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
2598                        struct task_struct *, unsigned long);
2599#else
2600extern int copy_thread(unsigned long, unsigned long, unsigned long,
2601                        struct task_struct *);
2602
2603/* Architectures that haven't opted into copy_thread_tls get the tls argument
2604 * via pt_regs, so ignore the tls argument passed via C. */
2605static inline int copy_thread_tls(
2606                unsigned long clone_flags, unsigned long sp, unsigned long arg,
2607                struct task_struct *p, unsigned long tls)
2608{
2609        return copy_thread(clone_flags, sp, arg, p);
2610}
2611#endif
2612extern void flush_thread(void);
2613extern void exit_thread(void);
2614
2615extern void exit_files(struct task_struct *);
2616extern void __cleanup_sighand(struct sighand_struct *);
2617
2618extern void exit_itimers(struct signal_struct *);
2619extern void flush_itimer_signals(void);
2620
2621extern void do_group_exit(int);
2622
2623extern int do_execve(struct filename *,
2624                     const char __user * const __user *,
2625                     const char __user * const __user *);
2626extern int do_execveat(int, struct filename *,
2627                       const char __user * const __user *,
2628                       const char __user * const __user *,
2629                       int);
2630extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2631extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2632struct task_struct *fork_idle(int);
2633extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2634
2635extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2636static inline void set_task_comm(struct task_struct *tsk, const char *from)
2637{
2638        __set_task_comm(tsk, from, false);
2639}
2640extern char *get_task_comm(char *to, struct task_struct *tsk);
2641
2642#ifdef CONFIG_SMP
2643void scheduler_ipi(void);
2644extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2645#else
2646static inline void scheduler_ipi(void) { }
2647static inline unsigned long wait_task_inactive(struct task_struct *p,
2648                                               long match_state)
2649{
2650        return 1;
2651}
2652#endif
2653
2654#define tasklist_empty() \
2655        list_empty(&init_task.tasks)
2656
2657#define next_task(p) \
2658        list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2659
2660#define for_each_process(p) \
2661        for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2662
2663extern bool current_is_single_threaded(void);
2664
2665/*
2666 * Careful: do_each_thread/while_each_thread is a double loop so
2667 *          'break' will not work as expected - use goto instead.
2668 */
2669#define do_each_thread(g, t) \
2670        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2671
2672#define while_each_thread(g, t) \
2673        while ((t = next_thread(t)) != g)
2674
2675#define __for_each_thread(signal, t)    \
2676        list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2677
2678#define for_each_thread(p, t)           \
2679        __for_each_thread((p)->signal, t)
2680
2681/* Careful: this is a double loop, 'break' won't work as expected. */
2682#define for_each_process_thread(p, t)   \
2683        for_each_process(p) for_each_thread(p, t)
2684
2685static inline int get_nr_threads(struct task_struct *tsk)
2686{
2687        return tsk->signal->nr_threads;
2688}
2689
2690static inline bool thread_group_leader(struct task_struct *p)
2691{
2692        return p->exit_signal >= 0;
2693}
2694
2695/* Do to the insanities of de_thread it is possible for a process
2696 * to have the pid of the thread group leader without actually being
2697 * the thread group leader.  For iteration through the pids in proc
2698 * all we care about is that we have a task with the appropriate
2699 * pid, we don't actually care if we have the right task.
2700 */
2701static inline bool has_group_leader_pid(struct task_struct *p)
2702{
2703        return task_pid(p) == p->signal->leader_pid;
2704}
2705
2706static inline
2707bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2708{
2709        return p1->signal == p2->signal;
2710}
2711
2712static inline struct task_struct *next_thread(const struct task_struct *p)
2713{
2714        return list_entry_rcu(p->thread_group.next,
2715                              struct task_struct, thread_group);
2716}
2717
2718static inline int thread_group_empty(struct task_struct *p)
2719{
2720        return list_empty(&p->thread_group);
2721}
2722
2723#define delay_group_leader(p) \
2724                (thread_group_leader(p) && !thread_group_empty(p))
2725
2726/*
2727 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2728 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2729 * pins the final release of task.io_context.  Also protects ->cpuset and
2730 * ->cgroup.subsys[]. And ->vfork_done.
2731 *
2732 * Nests both inside and outside of read_lock(&tasklist_lock).
2733 * It must not be nested with write_lock_irq(&tasklist_lock),
2734 * neither inside nor outside.
2735 */
2736static inline void task_lock(struct task_struct *p)
2737{
2738        spin_lock(&p->alloc_lock);
2739}
2740
2741static inline void task_unlock(struct task_struct *p)
2742{
2743        spin_unlock(&p->alloc_lock);
2744}
2745
2746extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2747                                                        unsigned long *flags);
2748
2749static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2750                                                       unsigned long *flags)
2751{
2752        struct sighand_struct *ret;
2753
2754        ret = __lock_task_sighand(tsk, flags);
2755        (void)__cond_lock(&tsk->sighand->siglock, ret);
2756        return ret;
2757}
2758
2759static inline void unlock_task_sighand(struct task_struct *tsk,
2760                                                unsigned long *flags)
2761{
2762        spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2763}
2764
2765/**
2766 * threadgroup_change_begin - mark the beginning of changes to a threadgroup
2767 * @tsk: task causing the changes
2768 *
2769 * All operations which modify a threadgroup - a new thread joining the
2770 * group, death of a member thread (the assertion of PF_EXITING) and
2771 * exec(2) dethreading the process and replacing the leader - are wrapped
2772 * by threadgroup_change_{begin|end}().  This is to provide a place which
2773 * subsystems needing threadgroup stability can hook into for
2774 * synchronization.
2775 */
2776static inline void threadgroup_change_begin(struct task_struct *tsk)
2777{
2778        might_sleep();
2779        cgroup_threadgroup_change_begin(tsk);
2780}
2781
2782/**
2783 * threadgroup_change_end - mark the end of changes to a threadgroup
2784 * @tsk: task causing the changes
2785 *
2786 * See threadgroup_change_begin().
2787 */
2788static inline void threadgroup_change_end(struct task_struct *tsk)
2789{
2790        cgroup_threadgroup_change_end(tsk);
2791}
2792
2793#ifndef __HAVE_THREAD_FUNCTIONS
2794
2795#define task_thread_info(task)  ((struct thread_info *)(task)->stack)
2796#define task_stack_page(task)   ((task)->stack)
2797
2798static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2799{
2800        *task_thread_info(p) = *task_thread_info(org);
2801        task_thread_info(p)->task = p;
2802}
2803
2804/*
2805 * Return the address of the last usable long on the stack.
2806 *
2807 * When the stack grows down, this is just above the thread
2808 * info struct. Going any lower will corrupt the threadinfo.
2809 *
2810 * When the stack grows up, this is the highest address.
2811 * Beyond that position, we corrupt data on the next page.
2812 */
2813static inline unsigned long *end_of_stack(struct task_struct *p)
2814{
2815#ifdef CONFIG_STACK_GROWSUP
2816        return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
2817#else
2818        return (unsigned long *)(task_thread_info(p) + 1);
2819#endif
2820}
2821
2822#endif
2823#define task_stack_end_corrupted(task) \
2824                (*(end_of_stack(task)) != STACK_END_MAGIC)
2825
2826static inline int object_is_on_stack(void *obj)
2827{
2828        void *stack = task_stack_page(current);
2829
2830        return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2831}
2832
2833extern void thread_info_cache_init(void);
2834
2835#ifdef CONFIG_DEBUG_STACK_USAGE
2836static inline unsigned long stack_not_used(struct task_struct *p)
2837{
2838        unsigned long *n = end_of_stack(p);
2839
2840        do {    /* Skip over canary */
2841                n++;
2842        } while (!*n);
2843
2844        return (unsigned long)n - (unsigned long)end_of_stack(p);
2845}
2846#endif
2847extern void set_task_stack_end_magic(struct task_struct *tsk);
2848
2849/* set thread flags in other task's structures
2850 * - see asm/thread_info.h for TIF_xxxx flags available
2851 */
2852static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2853{
2854        set_ti_thread_flag(task_thread_info(tsk), flag);
2855}
2856
2857static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2858{
2859        clear_ti_thread_flag(task_thread_info(tsk), flag);
2860}
2861
2862static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2863{
2864        return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2865}
2866
2867static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2868{
2869        return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2870}
2871
2872static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2873{
2874        return test_ti_thread_flag(task_thread_info(tsk), flag);
2875}
2876
2877static inline void set_tsk_need_resched(struct task_struct *tsk)
2878{
2879        set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2880}
2881
2882static inline void clear_tsk_need_resched(struct task_struct *tsk)
2883{
2884        clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2885}
2886
2887static inline int test_tsk_need_resched(struct task_struct *tsk)
2888{
2889        return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2890}
2891
2892static inline int restart_syscall(void)
2893{
2894        set_tsk_thread_flag(current, TIF_SIGPENDING);
2895        return -ERESTARTNOINTR;
2896}
2897
2898static inline int signal_pending(struct task_struct *p)
2899{
2900        return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2901}
2902
2903static inline int __fatal_signal_pending(struct task_struct *p)
2904{
2905        return unlikely(sigismember(&p->pending.signal, SIGKILL));
2906}
2907
2908static inline int fatal_signal_pending(struct task_struct *p)
2909{
2910        return signal_pending(p) && __fatal_signal_pending(p);
2911}
2912
2913static inline int signal_pending_state(long state, struct task_struct *p)
2914{
2915        if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2916                return 0;
2917        if (!signal_pending(p))
2918                return 0;
2919
2920        return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2921}
2922
2923/*
2924 * cond_resched() and cond_resched_lock(): latency reduction via
2925 * explicit rescheduling in places that are safe. The return
2926 * value indicates whether a reschedule was done in fact.
2927 * cond_resched_lock() will drop the spinlock before scheduling,
2928 * cond_resched_softirq() will enable bhs before scheduling.
2929 */
2930extern int _cond_resched(void);
2931
2932#define cond_resched() ({                       \
2933        ___might_sleep(__FILE__, __LINE__, 0);  \
2934        _cond_resched();                        \
2935})
2936
2937extern int __cond_resched_lock(spinlock_t *lock);
2938
2939#define cond_resched_lock(lock) ({                              \
2940        ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2941        __cond_resched_lock(lock);                              \
2942})
2943
2944extern int __cond_resched_softirq(void);
2945
2946#define cond_resched_softirq() ({                                       \
2947        ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);     \
2948        __cond_resched_softirq();                                       \
2949})
2950
2951static inline void cond_resched_rcu(void)
2952{
2953#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2954        rcu_read_unlock();
2955        cond_resched();
2956        rcu_read_lock();
2957#endif
2958}
2959
2960/*
2961 * Does a critical section need to be broken due to another
2962 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2963 * but a general need for low latency)
2964 */
2965static inline int spin_needbreak(spinlock_t *lock)
2966{
2967#ifdef CONFIG_PREEMPT
2968        return spin_is_contended(lock);
2969#else
2970        return 0;
2971#endif
2972}
2973
2974/*
2975 * Idle thread specific functions to determine the need_resched
2976 * polling state.
2977 */
2978#ifdef TIF_POLLING_NRFLAG
2979static inline int tsk_is_polling(struct task_struct *p)
2980{
2981        return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2982}
2983
2984static inline void __current_set_polling(void)
2985{
2986        set_thread_flag(TIF_POLLING_NRFLAG);
2987}
2988
2989static inline bool __must_check current_set_polling_and_test(void)
2990{
2991        __current_set_polling();
2992
2993        /*
2994         * Polling state must be visible before we test NEED_RESCHED,
2995         * paired by resched_curr()
2996         */
2997        smp_mb__after_atomic();
2998
2999        return unlikely(tif_need_resched());
3000}
3001
3002static inline void __current_clr_polling(void)
3003{
3004        clear_thread_flag(TIF_POLLING_NRFLAG);
3005}
3006
3007static inline bool __must_check current_clr_polling_and_test(void)
3008{
3009        __current_clr_polling();
3010
3011        /*
3012         * Polling state must be visible before we test NEED_RESCHED,
3013         * paired by resched_curr()
3014         */
3015        smp_mb__after_atomic();
3016
3017        return unlikely(tif_need_resched());
3018}
3019
3020#else
3021static inline int tsk_is_polling(struct task_struct *p) { return 0; }
3022static inline void __current_set_polling(void) { }
3023static inline void __current_clr_polling(void) { }
3024
3025static inline bool __must_check current_set_polling_and_test(void)
3026{
3027        return unlikely(tif_need_resched());
3028}
3029static inline bool __must_check current_clr_polling_and_test(void)
3030{
3031        return unlikely(tif_need_resched());
3032}
3033#endif
3034
3035static inline void current_clr_polling(void)
3036{
3037        __current_clr_polling();
3038
3039        /*
3040         * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
3041         * Once the bit is cleared, we'll get IPIs with every new
3042         * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
3043         * fold.
3044         */
3045        smp_mb(); /* paired with resched_curr() */
3046
3047        preempt_fold_need_resched();
3048}
3049
3050static __always_inline bool need_resched(void)
3051{
3052        return unlikely(tif_need_resched());
3053}
3054
3055/*
3056 * Thread group CPU time accounting.
3057 */
3058void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
3059void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
3060
3061/*
3062 * Reevaluate whether the task has signals pending delivery.
3063 * Wake the task if so.
3064 * This is required every time the blocked sigset_t changes.
3065 * callers must hold sighand->siglock.
3066 */
3067extern void recalc_sigpending_and_wake(struct task_struct *t);
3068extern void recalc_sigpending(void);
3069
3070extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
3071
3072static inline void signal_wake_up(struct task_struct *t, bool resume)
3073{
3074        signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
3075}
3076static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
3077{
3078        signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
3079}
3080
3081/*
3082 * Wrappers for p->thread_info->cpu access. No-op on UP.
3083 */
3084#ifdef CONFIG_SMP
3085
3086static inline unsigned int task_cpu(const struct task_struct *p)
3087{
3088        return task_thread_info(p)->cpu;
3089}
3090
3091static inline int task_node(const struct task_struct *p)
3092{
3093        return cpu_to_node(task_cpu(p));
3094}
3095
3096extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
3097
3098#else
3099
3100static inline unsigned int task_cpu(const struct task_struct *p)
3101{
3102        return 0;
3103}
3104
3105static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
3106{
3107}
3108
3109#endif /* CONFIG_SMP */
3110
3111extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3112extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3113
3114#ifdef CONFIG_CGROUP_SCHED
3115extern struct task_group root_task_group;
3116#endif /* CONFIG_CGROUP_SCHED */
3117
3118extern int task_can_switch_user(struct user_struct *up,
3119                                        struct task_struct *tsk);
3120
3121#ifdef CONFIG_TASK_XACCT
3122static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3123{
3124        tsk->ioac.rchar += amt;
3125}
3126
3127static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3128{
3129        tsk->ioac.wchar += amt;
3130}
3131
3132static inline void inc_syscr(struct task_struct *tsk)
3133{
3134        tsk->ioac.syscr++;
3135}
3136
3137static inline void inc_syscw(struct task_struct *tsk)
3138{
3139        tsk->ioac.syscw++;
3140}
3141#else
3142static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3143{
3144}
3145
3146static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3147{
3148}
3149
3150static inline void inc_syscr(struct task_struct *tsk)
3151{
3152}
3153
3154static inline void inc_syscw(struct task_struct *tsk)
3155{
3156}
3157#endif
3158
3159#ifndef TASK_SIZE_OF
3160#define TASK_SIZE_OF(tsk)       TASK_SIZE
3161#endif
3162
3163#ifdef CONFIG_MEMCG
3164extern void mm_update_next_owner(struct mm_struct *mm);
3165#else
3166static inline void mm_update_next_owner(struct mm_struct *mm)
3167{
3168}
3169#endif /* CONFIG_MEMCG */
3170
3171static inline unsigned long task_rlimit(const struct task_struct *tsk,
3172                unsigned int limit)
3173{
3174        return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3175}
3176
3177static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3178                unsigned int limit)
3179{
3180        return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3181}
3182
3183static inline unsigned long rlimit(unsigned int limit)
3184{
3185        return task_rlimit(current, limit);
3186}
3187
3188static inline unsigned long rlimit_max(unsigned int limit)
3189{
3190        return task_rlimit_max(current, limit);
3191}
3192
3193#endif
3194