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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; 387void lockup_detector_init(void); 388#else 389static inline void touch_softlockup_watchdog(void) 390{ 391} 392static inline void touch_softlockup_watchdog_sync(void) 393{ 394} 395static inline void touch_all_softlockup_watchdogs(void) 396{ 397} 398static inline void lockup_detector_init(void) 399{ 400} 401#endif 402 403#ifdef CONFIG_DETECT_HUNG_TASK 404void reset_hung_task_detector(void); 405#else 406static inline void reset_hung_task_detector(void) 407{ 408} 409#endif 410 411/* Attach to any functions which should be ignored in wchan output. */ 412#define __sched __attribute__((__section__(".sched.text"))) 413 414/* Linker adds these: start and end of __sched functions */ 415extern char __sched_text_start[], __sched_text_end[]; 416 417/* Is this address in the __sched functions? */ 418extern int in_sched_functions(unsigned long addr); 419 420#define MAX_SCHEDULE_TIMEOUT LONG_MAX 421extern signed long schedule_timeout(signed long timeout); 422extern signed long schedule_timeout_interruptible(signed long timeout); 423extern signed long schedule_timeout_killable(signed long timeout); 424extern signed long schedule_timeout_uninterruptible(signed long timeout); 425asmlinkage void schedule(void); 426extern void schedule_preempt_disabled(void); 427 428extern long io_schedule_timeout(long timeout); 429 430static inline void io_schedule(void) 431{ 432 io_schedule_timeout(MAX_SCHEDULE_TIMEOUT); 433} 434 435struct nsproxy; 436struct user_namespace; 437 438#ifdef CONFIG_MMU 439extern void arch_pick_mmap_layout(struct mm_struct *mm); 440extern unsigned long 441arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 442 unsigned long, unsigned long); 443extern unsigned long 444arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 445 unsigned long len, unsigned long pgoff, 446 unsigned long flags); 447#else 448static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 449#endif 450 451#define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 452#define SUID_DUMP_USER 1 /* Dump as user of process */ 453#define SUID_DUMP_ROOT 2 /* Dump as root */ 454 455/* mm flags */ 456 457/* for SUID_DUMP_* above */ 458#define MMF_DUMPABLE_BITS 2 459#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 460 461extern void set_dumpable(struct mm_struct *mm, int value); 462/* 463 * This returns the actual value of the suid_dumpable flag. For things 464 * that are using this for checking for privilege transitions, it must 465 * test against SUID_DUMP_USER rather than treating it as a boolean 466 * value. 467 */ 468static inline int __get_dumpable(unsigned long mm_flags) 469{ 470 return mm_flags & MMF_DUMPABLE_MASK; 471} 472 473static inline int get_dumpable(struct mm_struct *mm) 474{ 475 return __get_dumpable(mm->flags); 476} 477 478/* coredump filter bits */ 479#define MMF_DUMP_ANON_PRIVATE 2 480#define MMF_DUMP_ANON_SHARED 3 481#define MMF_DUMP_MAPPED_PRIVATE 4 482#define MMF_DUMP_MAPPED_SHARED 5 483#define MMF_DUMP_ELF_HEADERS 6 484#define MMF_DUMP_HUGETLB_PRIVATE 7 485#define MMF_DUMP_HUGETLB_SHARED 8 486 487#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 488#define MMF_DUMP_FILTER_BITS 7 489#define MMF_DUMP_FILTER_MASK \ 490 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 491#define MMF_DUMP_FILTER_DEFAULT \ 492 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 493 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 494 495#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 496# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 497#else 498# define MMF_DUMP_MASK_DEFAULT_ELF 0 499#endif 500 /* leave room for more dump flags */ 501#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 502#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 503#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 504 505#define MMF_HAS_UPROBES 19 /* has uprobes */ 506#define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 507 508#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 509 510struct sighand_struct { 511 atomic_t count; 512 struct k_sigaction action[_NSIG]; 513 spinlock_t siglock; 514 wait_queue_head_t signalfd_wqh; 515}; 516 517struct pacct_struct { 518 int ac_flag; 519 long ac_exitcode; 520 unsigned long ac_mem; 521 cputime_t ac_utime, ac_stime; 522 unsigned long ac_minflt, ac_majflt; 523}; 524 525struct cpu_itimer { 526 cputime_t expires; 527 cputime_t incr; 528 u32 error; 529 u32 incr_error; 530}; 531 532/** 533 * struct prev_cputime - snaphsot of system and user cputime 534 * @utime: time spent in user mode 535 * @stime: time spent in system mode 536 * @lock: protects the above two fields 537 * 538 * Stores previous user/system time values such that we can guarantee 539 * monotonicity. 540 */ 541struct prev_cputime { 542#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 543 cputime_t utime; 544 cputime_t stime; 545 raw_spinlock_t lock; 546#endif 547}; 548 549static inline void prev_cputime_init(struct prev_cputime *prev) 550{ 551#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 552 prev->utime = prev->stime = 0; 553 raw_spin_lock_init(&prev->lock); 554#endif 555} 556 557/** 558 * struct task_cputime - collected CPU time counts 559 * @utime: time spent in user mode, in &cputime_t units 560 * @stime: time spent in kernel mode, in &cputime_t units 561 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 562 * 563 * This structure groups together three kinds of CPU time that are tracked for 564 * threads and thread groups. Most things considering CPU time want to group 565 * these counts together and treat all three of them in parallel. 566 */ 567struct task_cputime { 568 cputime_t utime; 569 cputime_t stime; 570 unsigned long long sum_exec_runtime; 571}; 572 573/* Alternate field names when used to cache expirations. */ 574#define virt_exp utime 575#define prof_exp stime 576#define sched_exp sum_exec_runtime 577 578#define INIT_CPUTIME \ 579 (struct task_cputime) { \ 580 .utime = 0, \ 581 .stime = 0, \ 582 .sum_exec_runtime = 0, \ 583 } 584 585/* 586 * This is the atomic variant of task_cputime, which can be used for 587 * storing and updating task_cputime statistics without locking. 588 */ 589struct task_cputime_atomic { 590 atomic64_t utime; 591 atomic64_t stime; 592 atomic64_t sum_exec_runtime; 593}; 594 595#define INIT_CPUTIME_ATOMIC \ 596 (struct task_cputime_atomic) { \ 597 .utime = ATOMIC64_INIT(0), \ 598 .stime = ATOMIC64_INIT(0), \ 599 .sum_exec_runtime = ATOMIC64_INIT(0), \ 600 } 601 602#ifdef CONFIG_PREEMPT_COUNT 603#define PREEMPT_DISABLED (1 + PREEMPT_ENABLED) 604#else 605#define PREEMPT_DISABLED PREEMPT_ENABLED 606#endif 607 608/* 609 * Disable preemption until the scheduler is running. 610 * Reset by start_kernel()->sched_init()->init_idle(). 611 * 612 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 613 * before the scheduler is active -- see should_resched(). 614 */ 615#define INIT_PREEMPT_COUNT (PREEMPT_DISABLED + PREEMPT_ACTIVE) 616 617/** 618 * struct thread_group_cputimer - thread group interval timer counts 619 * @cputime_atomic: atomic thread group interval timers. 620 * @running: non-zero when there are timers running and 621 * @cputime receives updates. 622 * 623 * This structure contains the version of task_cputime, above, that is 624 * used for thread group CPU timer calculations. 625 */ 626struct thread_group_cputimer { 627 struct task_cputime_atomic cputime_atomic; 628 int running; 629}; 630 631#include <linux/rwsem.h> 632struct autogroup; 633 634/* 635 * NOTE! "signal_struct" does not have its own 636 * locking, because a shared signal_struct always 637 * implies a shared sighand_struct, so locking 638 * sighand_struct is always a proper superset of 639 * the locking of signal_struct. 640 */ 641struct signal_struct { 642 atomic_t sigcnt; 643 atomic_t live; 644 int nr_threads; 645 struct list_head thread_head; 646 647 wait_queue_head_t wait_chldexit; /* for wait4() */ 648 649 /* current thread group signal load-balancing target: */ 650 struct task_struct *curr_target; 651 652 /* shared signal handling: */ 653 struct sigpending shared_pending; 654 655 /* thread group exit support */ 656 int group_exit_code; 657 /* overloaded: 658 * - notify group_exit_task when ->count is equal to notify_count 659 * - everyone except group_exit_task is stopped during signal delivery 660 * of fatal signals, group_exit_task processes the signal. 661 */ 662 int notify_count; 663 struct task_struct *group_exit_task; 664 665 /* thread group stop support, overloads group_exit_code too */ 666 int group_stop_count; 667 unsigned int flags; /* see SIGNAL_* flags below */ 668 669 /* 670 * PR_SET_CHILD_SUBREAPER marks a process, like a service 671 * manager, to re-parent orphan (double-forking) child processes 672 * to this process instead of 'init'. The service manager is 673 * able to receive SIGCHLD signals and is able to investigate 674 * the process until it calls wait(). All children of this 675 * process will inherit a flag if they should look for a 676 * child_subreaper process at exit. 677 */ 678 unsigned int is_child_subreaper:1; 679 unsigned int has_child_subreaper:1; 680 681 /* POSIX.1b Interval Timers */ 682 int posix_timer_id; 683 struct list_head posix_timers; 684 685 /* ITIMER_REAL timer for the process */ 686 struct hrtimer real_timer; 687 struct pid *leader_pid; 688 ktime_t it_real_incr; 689 690 /* 691 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 692 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 693 * values are defined to 0 and 1 respectively 694 */ 695 struct cpu_itimer it[2]; 696 697 /* 698 * Thread group totals for process CPU timers. 699 * See thread_group_cputimer(), et al, for details. 700 */ 701 struct thread_group_cputimer cputimer; 702 703 /* Earliest-expiration cache. */ 704 struct task_cputime cputime_expires; 705 706 struct list_head cpu_timers[3]; 707 708 struct pid *tty_old_pgrp; 709 710 /* boolean value for session group leader */ 711 int leader; 712 713 struct tty_struct *tty; /* NULL if no tty */ 714 715#ifdef CONFIG_SCHED_AUTOGROUP 716 struct autogroup *autogroup; 717#endif 718 /* 719 * Cumulative resource counters for dead threads in the group, 720 * and for reaped dead child processes forked by this group. 721 * Live threads maintain their own counters and add to these 722 * in __exit_signal, except for the group leader. 723 */ 724 seqlock_t stats_lock; 725 cputime_t utime, stime, cutime, cstime; 726 cputime_t gtime; 727 cputime_t cgtime; 728 struct prev_cputime prev_cputime; 729 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 730 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 731 unsigned long inblock, oublock, cinblock, coublock; 732 unsigned long maxrss, cmaxrss; 733 struct task_io_accounting ioac; 734 735 /* 736 * Cumulative ns of schedule CPU time fo dead threads in the 737 * group, not including a zombie group leader, (This only differs 738 * from jiffies_to_ns(utime + stime) if sched_clock uses something 739 * other than jiffies.) 740 */ 741 unsigned long long sum_sched_runtime; 742 743 /* 744 * We don't bother to synchronize most readers of this at all, 745 * because there is no reader checking a limit that actually needs 746 * to get both rlim_cur and rlim_max atomically, and either one 747 * alone is a single word that can safely be read normally. 748 * getrlimit/setrlimit use task_lock(current->group_leader) to 749 * protect this instead of the siglock, because they really 750 * have no need to disable irqs. 751 */ 752 struct rlimit rlim[RLIM_NLIMITS]; 753 754#ifdef CONFIG_BSD_PROCESS_ACCT 755 struct pacct_struct pacct; /* per-process accounting information */ 756#endif 757#ifdef CONFIG_TASKSTATS 758 struct taskstats *stats; 759#endif 760#ifdef CONFIG_AUDIT 761 unsigned audit_tty; 762 unsigned audit_tty_log_passwd; 763 struct tty_audit_buf *tty_audit_buf; 764#endif 765#ifdef CONFIG_CGROUPS 766 /* 767 * group_rwsem prevents new tasks from entering the threadgroup and 768 * member tasks from exiting,a more specifically, setting of 769 * PF_EXITING. fork and exit paths are protected with this rwsem 770 * using threadgroup_change_begin/end(). Users which require 771 * threadgroup to remain stable should use threadgroup_[un]lock() 772 * which also takes care of exec path. Currently, cgroup is the 773 * only user. 774 */ 775 struct rw_semaphore group_rwsem; 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#ifdef CONFIG_PERF_EVENTS 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 struct sched_domain_topology_level *sched_domain_topology; 1143 1144extern void set_sched_topology(struct sched_domain_topology_level *tl); 1145extern void wake_up_if_idle(int cpu); 1146 1147#ifdef CONFIG_SCHED_DEBUG 1148# define SD_INIT_NAME(type) .name = #type 1149#else 1150# define SD_INIT_NAME(type) 1151#endif 1152 1153#else /* CONFIG_SMP */ 1154 1155struct sched_domain_attr; 1156 1157static inline void 1158partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1159 struct sched_domain_attr *dattr_new) 1160{ 1161} 1162 1163static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1164{ 1165 return true; 1166} 1167 1168#endif /* !CONFIG_SMP */ 1169 1170 1171struct io_context; /* See blkdev.h */ 1172 1173 1174#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1175extern void prefetch_stack(struct task_struct *t); 1176#else 1177static inline void prefetch_stack(struct task_struct *t) { } 1178#endif 1179 1180struct audit_context; /* See audit.c */ 1181struct mempolicy; 1182struct pipe_inode_info; 1183struct uts_namespace; 1184 1185struct load_weight { 1186 unsigned long weight; 1187 u32 inv_weight; 1188}; 1189 1190/* 1191 * The load_avg/util_avg accumulates an infinite geometric series. 1192 * 1) load_avg factors the amount of time that a sched_entity is 1193 * runnable on a rq into its weight. For cfs_rq, it is the aggregated 1194 * such weights of all runnable and blocked sched_entities. 1195 * 2) util_avg factors frequency scaling into the amount of time 1196 * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE]. 1197 * For cfs_rq, it is the aggregated such times of all runnable and 1198 * blocked sched_entities. 1199 * The 64 bit load_sum can: 1200 * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with 1201 * the highest weight (=88761) always runnable, we should not overflow 1202 * 2) for entity, support any load.weight always runnable 1203 */ 1204struct sched_avg { 1205 u64 last_update_time, load_sum; 1206 u32 util_sum, period_contrib; 1207 unsigned long load_avg, util_avg; 1208}; 1209 1210#ifdef CONFIG_SCHEDSTATS 1211struct sched_statistics { 1212 u64 wait_start; 1213 u64 wait_max; 1214 u64 wait_count; 1215 u64 wait_sum; 1216 u64 iowait_count; 1217 u64 iowait_sum; 1218 1219 u64 sleep_start; 1220 u64 sleep_max; 1221 s64 sum_sleep_runtime; 1222 1223 u64 block_start; 1224 u64 block_max; 1225 u64 exec_max; 1226 u64 slice_max; 1227 1228 u64 nr_migrations_cold; 1229 u64 nr_failed_migrations_affine; 1230 u64 nr_failed_migrations_running; 1231 u64 nr_failed_migrations_hot; 1232 u64 nr_forced_migrations; 1233 1234 u64 nr_wakeups; 1235 u64 nr_wakeups_sync; 1236 u64 nr_wakeups_migrate; 1237 u64 nr_wakeups_local; 1238 u64 nr_wakeups_remote; 1239 u64 nr_wakeups_affine; 1240 u64 nr_wakeups_affine_attempts; 1241 u64 nr_wakeups_passive; 1242 u64 nr_wakeups_idle; 1243}; 1244#endif 1245 1246struct sched_entity { 1247 struct load_weight load; /* for load-balancing */ 1248 struct rb_node run_node; 1249 struct list_head group_node; 1250 unsigned int on_rq; 1251 1252 u64 exec_start; 1253 u64 sum_exec_runtime; 1254 u64 vruntime; 1255 u64 prev_sum_exec_runtime; 1256 1257 u64 nr_migrations; 1258 1259#ifdef CONFIG_SCHEDSTATS 1260 struct sched_statistics statistics; 1261#endif 1262 1263#ifdef CONFIG_FAIR_GROUP_SCHED 1264 int depth; 1265 struct sched_entity *parent; 1266 /* rq on which this entity is (to be) queued: */ 1267 struct cfs_rq *cfs_rq; 1268 /* rq "owned" by this entity/group: */ 1269 struct cfs_rq *my_q; 1270#endif 1271 1272#ifdef CONFIG_SMP 1273 /* Per entity load average tracking */ 1274 struct sched_avg avg; 1275#endif 1276}; 1277 1278struct sched_rt_entity { 1279 struct list_head run_list; 1280 unsigned long timeout; 1281 unsigned long watchdog_stamp; 1282 unsigned int time_slice; 1283 1284 struct sched_rt_entity *back; 1285#ifdef CONFIG_RT_GROUP_SCHED 1286 struct sched_rt_entity *parent; 1287 /* rq on which this entity is (to be) queued: */ 1288 struct rt_rq *rt_rq; 1289 /* rq "owned" by this entity/group: */ 1290 struct rt_rq *my_q; 1291#endif 1292}; 1293 1294struct sched_dl_entity { 1295 struct rb_node rb_node; 1296 1297 /* 1298 * Original scheduling parameters. Copied here from sched_attr 1299 * during sched_setattr(), they will remain the same until 1300 * the next sched_setattr(). 1301 */ 1302 u64 dl_runtime; /* maximum runtime for each instance */ 1303 u64 dl_deadline; /* relative deadline of each instance */ 1304 u64 dl_period; /* separation of two instances (period) */ 1305 u64 dl_bw; /* dl_runtime / dl_deadline */ 1306 1307 /* 1308 * Actual scheduling parameters. Initialized with the values above, 1309 * they are continously updated during task execution. Note that 1310 * the remaining runtime could be < 0 in case we are in overrun. 1311 */ 1312 s64 runtime; /* remaining runtime for this instance */ 1313 u64 deadline; /* absolute deadline for this instance */ 1314 unsigned int flags; /* specifying the scheduler behaviour */ 1315 1316 /* 1317 * Some bool flags: 1318 * 1319 * @dl_throttled tells if we exhausted the runtime. If so, the 1320 * task has to wait for a replenishment to be performed at the 1321 * next firing of dl_timer. 1322 * 1323 * @dl_new tells if a new instance arrived. If so we must 1324 * start executing it with full runtime and reset its absolute 1325 * deadline; 1326 * 1327 * @dl_boosted tells if we are boosted due to DI. If so we are 1328 * outside bandwidth enforcement mechanism (but only until we 1329 * exit the critical section); 1330 * 1331 * @dl_yielded tells if task gave up the cpu before consuming 1332 * all its available runtime during the last job. 1333 */ 1334 int dl_throttled, dl_new, dl_boosted, dl_yielded; 1335 1336 /* 1337 * Bandwidth enforcement timer. Each -deadline task has its 1338 * own bandwidth to be enforced, thus we need one timer per task. 1339 */ 1340 struct hrtimer dl_timer; 1341}; 1342 1343union rcu_special { 1344 struct { 1345 bool blocked; 1346 bool need_qs; 1347 } b; 1348 short s; 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 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1459 * execve */ 1460 unsigned in_iowait:1; 1461 1462 /* Revert to default priority/policy when forking */ 1463 unsigned sched_reset_on_fork:1; 1464 unsigned sched_contributes_to_load:1; 1465 unsigned sched_migrated:1; 1466 1467#ifdef CONFIG_MEMCG_KMEM 1468 unsigned memcg_kmem_skip_account:1; 1469#endif 1470#ifdef CONFIG_COMPAT_BRK 1471 unsigned brk_randomized:1; 1472#endif 1473 1474 unsigned long atomic_flags; /* Flags needing atomic access. */ 1475 1476 struct restart_block restart_block; 1477 1478 pid_t pid; 1479 pid_t tgid; 1480 1481#ifdef CONFIG_CC_STACKPROTECTOR 1482 /* Canary value for the -fstack-protector gcc feature */ 1483 unsigned long stack_canary; 1484#endif 1485 /* 1486 * pointers to (original) parent process, youngest child, younger sibling, 1487 * older sibling, respectively. (p->father can be replaced with 1488 * p->real_parent->pid) 1489 */ 1490 struct task_struct __rcu *real_parent; /* real parent process */ 1491 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1492 /* 1493 * children/sibling forms the list of my natural children 1494 */ 1495 struct list_head children; /* list of my children */ 1496 struct list_head sibling; /* linkage in my parent's children list */ 1497 struct task_struct *group_leader; /* threadgroup leader */ 1498 1499 /* 1500 * ptraced is the list of tasks this task is using ptrace on. 1501 * This includes both natural children and PTRACE_ATTACH targets. 1502 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1503 */ 1504 struct list_head ptraced; 1505 struct list_head ptrace_entry; 1506 1507 /* PID/PID hash table linkage. */ 1508 struct pid_link pids[PIDTYPE_MAX]; 1509 struct list_head thread_group; 1510 struct list_head thread_node; 1511 1512 struct completion *vfork_done; /* for vfork() */ 1513 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1514 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1515 1516 cputime_t utime, stime, utimescaled, stimescaled; 1517 cputime_t gtime; 1518 struct prev_cputime prev_cputime; 1519#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1520 seqlock_t vtime_seqlock; 1521 unsigned long long vtime_snap; 1522 enum { 1523 VTIME_SLEEPING = 0, 1524 VTIME_USER, 1525 VTIME_SYS, 1526 } vtime_snap_whence; 1527#endif 1528 unsigned long nvcsw, nivcsw; /* context switch counts */ 1529 u64 start_time; /* monotonic time in nsec */ 1530 u64 real_start_time; /* boot based time in nsec */ 1531/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1532 unsigned long min_flt, maj_flt; 1533 1534 struct task_cputime cputime_expires; 1535 struct list_head cpu_timers[3]; 1536 1537/* process credentials */ 1538 const struct cred __rcu *real_cred; /* objective and real subjective task 1539 * credentials (COW) */ 1540 const struct cred __rcu *cred; /* effective (overridable) subjective task 1541 * credentials (COW) */ 1542 char comm[TASK_COMM_LEN]; /* executable name excluding path 1543 - access with [gs]et_task_comm (which lock 1544 it with task_lock()) 1545 - initialized normally by setup_new_exec */ 1546/* file system info */ 1547 struct nameidata *nameidata; 1548#ifdef CONFIG_SYSVIPC 1549/* ipc stuff */ 1550 struct sysv_sem sysvsem; 1551 struct sysv_shm sysvshm; 1552#endif 1553#ifdef CONFIG_DETECT_HUNG_TASK 1554/* hung task detection */ 1555 unsigned long last_switch_count; 1556#endif 1557/* filesystem information */ 1558 struct fs_struct *fs; 1559/* open file information */ 1560 struct files_struct *files; 1561/* namespaces */ 1562 struct nsproxy *nsproxy; 1563/* signal handlers */ 1564 struct signal_struct *signal; 1565 struct sighand_struct *sighand; 1566 1567 sigset_t blocked, real_blocked; 1568 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1569 struct sigpending pending; 1570 1571 unsigned long sas_ss_sp; 1572 size_t sas_ss_size; 1573 int (*notifier)(void *priv); 1574 void *notifier_data; 1575 sigset_t *notifier_mask; 1576 struct callback_head *task_works; 1577 1578 struct audit_context *audit_context; 1579#ifdef CONFIG_AUDITSYSCALL 1580 kuid_t loginuid; 1581 unsigned int sessionid; 1582#endif 1583 struct seccomp seccomp; 1584 1585/* Thread group tracking */ 1586 u32 parent_exec_id; 1587 u32 self_exec_id; 1588/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1589 * mempolicy */ 1590 spinlock_t alloc_lock; 1591 1592 /* Protection of the PI data structures: */ 1593 raw_spinlock_t pi_lock; 1594 1595 struct wake_q_node wake_q; 1596 1597#ifdef CONFIG_RT_MUTEXES 1598 /* PI waiters blocked on a rt_mutex held by this task */ 1599 struct rb_root pi_waiters; 1600 struct rb_node *pi_waiters_leftmost; 1601 /* Deadlock detection and priority inheritance handling */ 1602 struct rt_mutex_waiter *pi_blocked_on; 1603#endif 1604 1605#ifdef CONFIG_DEBUG_MUTEXES 1606 /* mutex deadlock detection */ 1607 struct mutex_waiter *blocked_on; 1608#endif 1609#ifdef CONFIG_TRACE_IRQFLAGS 1610 unsigned int irq_events; 1611 unsigned long hardirq_enable_ip; 1612 unsigned long hardirq_disable_ip; 1613 unsigned int hardirq_enable_event; 1614 unsigned int hardirq_disable_event; 1615 int hardirqs_enabled; 1616 int hardirq_context; 1617 unsigned long softirq_disable_ip; 1618 unsigned long softirq_enable_ip; 1619 unsigned int softirq_disable_event; 1620 unsigned int softirq_enable_event; 1621 int softirqs_enabled; 1622 int softirq_context; 1623#endif 1624#ifdef CONFIG_LOCKDEP 1625# define MAX_LOCK_DEPTH 48UL 1626 u64 curr_chain_key; 1627 int lockdep_depth; 1628 unsigned int lockdep_recursion; 1629 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1630 gfp_t lockdep_reclaim_gfp; 1631#endif 1632 1633/* journalling filesystem info */ 1634 void *journal_info; 1635 1636/* stacked block device info */ 1637 struct bio_list *bio_list; 1638 1639#ifdef CONFIG_BLOCK 1640/* stack plugging */ 1641 struct blk_plug *plug; 1642#endif 1643 1644/* VM state */ 1645 struct reclaim_state *reclaim_state; 1646 1647 struct backing_dev_info *backing_dev_info; 1648 1649 struct io_context *io_context; 1650 1651 unsigned long ptrace_message; 1652 siginfo_t *last_siginfo; /* For ptrace use. */ 1653 struct task_io_accounting ioac; 1654#if defined(CONFIG_TASK_XACCT) 1655 u64 acct_rss_mem1; /* accumulated rss usage */ 1656 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1657 cputime_t acct_timexpd; /* stime + utime since last update */ 1658#endif 1659#ifdef CONFIG_CPUSETS 1660 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1661 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1662 int cpuset_mem_spread_rotor; 1663 int cpuset_slab_spread_rotor; 1664#endif 1665#ifdef CONFIG_CGROUPS 1666 /* Control Group info protected by css_set_lock */ 1667 struct css_set __rcu *cgroups; 1668 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1669 struct list_head cg_list; 1670#endif 1671#ifdef CONFIG_FUTEX 1672 struct robust_list_head __user *robust_list; 1673#ifdef CONFIG_COMPAT 1674 struct compat_robust_list_head __user *compat_robust_list; 1675#endif 1676 struct list_head pi_state_list; 1677 struct futex_pi_state *pi_state_cache; 1678#endif 1679#ifdef CONFIG_PERF_EVENTS 1680 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1681 struct mutex perf_event_mutex; 1682 struct list_head perf_event_list; 1683#endif 1684#ifdef CONFIG_DEBUG_PREEMPT 1685 unsigned long preempt_disable_ip; 1686#endif 1687#ifdef CONFIG_NUMA 1688 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1689 short il_next; 1690 short pref_node_fork; 1691#endif 1692#ifdef CONFIG_NUMA_BALANCING 1693 int numa_scan_seq; 1694 unsigned int numa_scan_period; 1695 unsigned int numa_scan_period_max; 1696 int numa_preferred_nid; 1697 unsigned long numa_migrate_retry; 1698 u64 node_stamp; /* migration stamp */ 1699 u64 last_task_numa_placement; 1700 u64 last_sum_exec_runtime; 1701 struct callback_head numa_work; 1702 1703 struct list_head numa_entry; 1704 struct numa_group *numa_group; 1705 1706 /* 1707 * numa_faults is an array split into four regions: 1708 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1709 * in this precise order. 1710 * 1711 * faults_memory: Exponential decaying average of faults on a per-node 1712 * basis. Scheduling placement decisions are made based on these 1713 * counts. The values remain static for the duration of a PTE scan. 1714 * faults_cpu: Track the nodes the process was running on when a NUMA 1715 * hinting fault was incurred. 1716 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1717 * during the current scan window. When the scan completes, the counts 1718 * in faults_memory and faults_cpu decay and these values are copied. 1719 */ 1720 unsigned long *numa_faults; 1721 unsigned long total_numa_faults; 1722 1723 /* 1724 * numa_faults_locality tracks if faults recorded during the last 1725 * scan window were remote/local or failed to migrate. The task scan 1726 * period is adapted based on the locality of the faults with different 1727 * weights depending on whether they were shared or private faults 1728 */ 1729 unsigned long numa_faults_locality[3]; 1730 1731 unsigned long numa_pages_migrated; 1732#endif /* CONFIG_NUMA_BALANCING */ 1733 1734#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 1735 struct tlbflush_unmap_batch tlb_ubc; 1736#endif 1737 1738 struct rcu_head rcu; 1739 1740 /* 1741 * cache last used pipe for splice 1742 */ 1743 struct pipe_inode_info *splice_pipe; 1744 1745 struct page_frag task_frag; 1746 1747#ifdef CONFIG_TASK_DELAY_ACCT 1748 struct task_delay_info *delays; 1749#endif 1750#ifdef CONFIG_FAULT_INJECTION 1751 int make_it_fail; 1752#endif 1753 /* 1754 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1755 * balance_dirty_pages() for some dirty throttling pause 1756 */ 1757 int nr_dirtied; 1758 int nr_dirtied_pause; 1759 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1760 1761#ifdef CONFIG_LATENCYTOP 1762 int latency_record_count; 1763 struct latency_record latency_record[LT_SAVECOUNT]; 1764#endif 1765 /* 1766 * time slack values; these are used to round up poll() and 1767 * select() etc timeout values. These are in nanoseconds. 1768 */ 1769 unsigned long timer_slack_ns; 1770 unsigned long default_timer_slack_ns; 1771 1772#ifdef CONFIG_KASAN 1773 unsigned int kasan_depth; 1774#endif 1775#ifdef CONFIG_FUNCTION_GRAPH_TRACER 1776 /* Index of current stored address in ret_stack */ 1777 int curr_ret_stack; 1778 /* Stack of return addresses for return function tracing */ 1779 struct ftrace_ret_stack *ret_stack; 1780 /* time stamp for last schedule */ 1781 unsigned long long ftrace_timestamp; 1782 /* 1783 * Number of functions that haven't been traced 1784 * because of depth overrun. 1785 */ 1786 atomic_t trace_overrun; 1787 /* Pause for the tracing */ 1788 atomic_t tracing_graph_pause; 1789#endif 1790#ifdef CONFIG_TRACING 1791 /* state flags for use by tracers */ 1792 unsigned long trace; 1793 /* bitmask and counter of trace recursion */ 1794 unsigned long trace_recursion; 1795#endif /* CONFIG_TRACING */ 1796#ifdef CONFIG_MEMCG 1797 struct memcg_oom_info { 1798 struct mem_cgroup *memcg; 1799 gfp_t gfp_mask; 1800 int order; 1801 unsigned int may_oom:1; 1802 } memcg_oom; 1803#endif 1804#ifdef CONFIG_UPROBES 1805 struct uprobe_task *utask; 1806#endif 1807#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1808 unsigned int sequential_io; 1809 unsigned int sequential_io_avg; 1810#endif 1811#ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1812 unsigned long task_state_change; 1813#endif 1814 int pagefault_disabled; 1815/* CPU-specific state of this task */ 1816 struct thread_struct thread; 1817/* 1818 * WARNING: on x86, 'thread_struct' contains a variable-sized 1819 * structure. It *MUST* be at the end of 'task_struct'. 1820 * 1821 * Do not put anything below here! 1822 */ 1823}; 1824 1825#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT 1826extern int arch_task_struct_size __read_mostly; 1827#else 1828# define arch_task_struct_size (sizeof(struct task_struct)) 1829#endif 1830 1831/* Future-safe accessor for struct task_struct's cpus_allowed. */ 1832#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1833 1834#define TNF_MIGRATED 0x01 1835#define TNF_NO_GROUP 0x02 1836#define TNF_SHARED 0x04 1837#define TNF_FAULT_LOCAL 0x08 1838#define TNF_MIGRATE_FAIL 0x10 1839 1840#ifdef CONFIG_NUMA_BALANCING 1841extern void task_numa_fault(int last_node, int node, int pages, int flags); 1842extern pid_t task_numa_group_id(struct task_struct *p); 1843extern void set_numabalancing_state(bool enabled); 1844extern void task_numa_free(struct task_struct *p); 1845extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page, 1846 int src_nid, int dst_cpu); 1847#else 1848static inline void task_numa_fault(int last_node, int node, int pages, 1849 int flags) 1850{ 1851} 1852static inline pid_t task_numa_group_id(struct task_struct *p) 1853{ 1854 return 0; 1855} 1856static inline void set_numabalancing_state(bool enabled) 1857{ 1858} 1859static inline void task_numa_free(struct task_struct *p) 1860{ 1861} 1862static inline bool should_numa_migrate_memory(struct task_struct *p, 1863 struct page *page, int src_nid, int dst_cpu) 1864{ 1865 return true; 1866} 1867#endif 1868 1869static inline struct pid *task_pid(struct task_struct *task) 1870{ 1871 return task->pids[PIDTYPE_PID].pid; 1872} 1873 1874static inline struct pid *task_tgid(struct task_struct *task) 1875{ 1876 return task->group_leader->pids[PIDTYPE_PID].pid; 1877} 1878 1879/* 1880 * Without tasklist or rcu lock it is not safe to dereference 1881 * the result of task_pgrp/task_session even if task == current, 1882 * we can race with another thread doing sys_setsid/sys_setpgid. 1883 */ 1884static inline struct pid *task_pgrp(struct task_struct *task) 1885{ 1886 return task->group_leader->pids[PIDTYPE_PGID].pid; 1887} 1888 1889static inline struct pid *task_session(struct task_struct *task) 1890{ 1891 return task->group_leader->pids[PIDTYPE_SID].pid; 1892} 1893 1894struct pid_namespace; 1895 1896/* 1897 * the helpers to get the task's different pids as they are seen 1898 * from various namespaces 1899 * 1900 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1901 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1902 * current. 1903 * task_xid_nr_ns() : id seen from the ns specified; 1904 * 1905 * set_task_vxid() : assigns a virtual id to a task; 1906 * 1907 * see also pid_nr() etc in include/linux/pid.h 1908 */ 1909pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1910 struct pid_namespace *ns); 1911 1912static inline pid_t task_pid_nr(struct task_struct *tsk) 1913{ 1914 return tsk->pid; 1915} 1916 1917static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1918 struct pid_namespace *ns) 1919{ 1920 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1921} 1922 1923static inline pid_t task_pid_vnr(struct task_struct *tsk) 1924{ 1925 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1926} 1927 1928 1929static inline pid_t task_tgid_nr(struct task_struct *tsk) 1930{ 1931 return tsk->tgid; 1932} 1933 1934pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1935 1936static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1937{ 1938 return pid_vnr(task_tgid(tsk)); 1939} 1940 1941 1942static inline int pid_alive(const struct task_struct *p); 1943static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 1944{ 1945 pid_t pid = 0; 1946 1947 rcu_read_lock(); 1948 if (pid_alive(tsk)) 1949 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 1950 rcu_read_unlock(); 1951 1952 return pid; 1953} 1954 1955static inline pid_t task_ppid_nr(const struct task_struct *tsk) 1956{ 1957 return task_ppid_nr_ns(tsk, &init_pid_ns); 1958} 1959 1960static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1961 struct pid_namespace *ns) 1962{ 1963 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1964} 1965 1966static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1967{ 1968 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1969} 1970 1971 1972static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1973 struct pid_namespace *ns) 1974{ 1975 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1976} 1977 1978static inline pid_t task_session_vnr(struct task_struct *tsk) 1979{ 1980 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1981} 1982 1983/* obsolete, do not use */ 1984static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1985{ 1986 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1987} 1988 1989/** 1990 * pid_alive - check that a task structure is not stale 1991 * @p: Task structure to be checked. 1992 * 1993 * Test if a process is not yet dead (at most zombie state) 1994 * If pid_alive fails, then pointers within the task structure 1995 * can be stale and must not be dereferenced. 1996 * 1997 * Return: 1 if the process is alive. 0 otherwise. 1998 */ 1999static inline int pid_alive(const struct task_struct *p) 2000{ 2001 return p->pids[PIDTYPE_PID].pid != NULL; 2002} 2003 2004/** 2005 * is_global_init - check if a task structure is init 2006 * @tsk: Task structure to be checked. 2007 * 2008 * Check if a task structure is the first user space task the kernel created. 2009 * 2010 * Return: 1 if the task structure is init. 0 otherwise. 2011 */ 2012static inline int is_global_init(struct task_struct *tsk) 2013{ 2014 return tsk->pid == 1; 2015} 2016 2017extern struct pid *cad_pid; 2018 2019extern void free_task(struct task_struct *tsk); 2020#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 2021 2022extern void __put_task_struct(struct task_struct *t); 2023 2024static inline void put_task_struct(struct task_struct *t) 2025{ 2026 if (atomic_dec_and_test(&t->usage)) 2027 __put_task_struct(t); 2028} 2029 2030#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 2031extern void task_cputime(struct task_struct *t, 2032 cputime_t *utime, cputime_t *stime); 2033extern void task_cputime_scaled(struct task_struct *t, 2034 cputime_t *utimescaled, cputime_t *stimescaled); 2035extern cputime_t task_gtime(struct task_struct *t); 2036#else 2037static inline void task_cputime(struct task_struct *t, 2038 cputime_t *utime, cputime_t *stime) 2039{ 2040 if (utime) 2041 *utime = t->utime; 2042 if (stime) 2043 *stime = t->stime; 2044} 2045 2046static inline void task_cputime_scaled(struct task_struct *t, 2047 cputime_t *utimescaled, 2048 cputime_t *stimescaled) 2049{ 2050 if (utimescaled) 2051 *utimescaled = t->utimescaled; 2052 if (stimescaled) 2053 *stimescaled = t->stimescaled; 2054} 2055 2056static inline cputime_t task_gtime(struct task_struct *t) 2057{ 2058 return t->gtime; 2059} 2060#endif 2061extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2062extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2063 2064/* 2065 * Per process flags 2066 */ 2067#define PF_EXITING 0x00000004 /* getting shut down */ 2068#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 2069#define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 2070#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 2071#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 2072#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 2073#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 2074#define PF_DUMPCORE 0x00000200 /* dumped core */ 2075#define PF_SIGNALED 0x00000400 /* killed by a signal */ 2076#define PF_MEMALLOC 0x00000800 /* Allocating memory */ 2077#define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 2078#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 2079#define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 2080#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 2081#define PF_FROZEN 0x00010000 /* frozen for system suspend */ 2082#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 2083#define PF_KSWAPD 0x00040000 /* I am kswapd */ 2084#define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 2085#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 2086#define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 2087#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 2088#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 2089#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 2090#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 2091#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 2092#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 2093#define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 2094 2095/* 2096 * Only the _current_ task can read/write to tsk->flags, but other 2097 * tasks can access tsk->flags in readonly mode for example 2098 * with tsk_used_math (like during threaded core dumping). 2099 * There is however an exception to this rule during ptrace 2100 * or during fork: the ptracer task is allowed to write to the 2101 * child->flags of its traced child (same goes for fork, the parent 2102 * can write to the child->flags), because we're guaranteed the 2103 * child is not running and in turn not changing child->flags 2104 * at the same time the parent does it. 2105 */ 2106#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 2107#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 2108#define clear_used_math() clear_stopped_child_used_math(current) 2109#define set_used_math() set_stopped_child_used_math(current) 2110#define conditional_stopped_child_used_math(condition, child) \ 2111 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 2112#define conditional_used_math(condition) \ 2113 conditional_stopped_child_used_math(condition, current) 2114#define copy_to_stopped_child_used_math(child) \ 2115 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 2116/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 2117#define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 2118#define used_math() tsk_used_math(current) 2119 2120/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags 2121 * __GFP_FS is also cleared as it implies __GFP_IO. 2122 */ 2123static inline gfp_t memalloc_noio_flags(gfp_t flags) 2124{ 2125 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 2126 flags &= ~(__GFP_IO | __GFP_FS); 2127 return flags; 2128} 2129 2130static inline unsigned int memalloc_noio_save(void) 2131{ 2132 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 2133 current->flags |= PF_MEMALLOC_NOIO; 2134 return flags; 2135} 2136 2137static inline void memalloc_noio_restore(unsigned int flags) 2138{ 2139 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 2140} 2141 2142/* Per-process atomic flags. */ 2143#define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 2144#define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 2145#define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 2146 2147 2148#define TASK_PFA_TEST(name, func) \ 2149 static inline bool task_##func(struct task_struct *p) \ 2150 { return test_bit(PFA_##name, &p->atomic_flags); } 2151#define TASK_PFA_SET(name, func) \ 2152 static inline void task_set_##func(struct task_struct *p) \ 2153 { set_bit(PFA_##name, &p->atomic_flags); } 2154#define TASK_PFA_CLEAR(name, func) \ 2155 static inline void task_clear_##func(struct task_struct *p) \ 2156 { clear_bit(PFA_##name, &p->atomic_flags); } 2157 2158TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 2159TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 2160 2161TASK_PFA_TEST(SPREAD_PAGE, spread_page) 2162TASK_PFA_SET(SPREAD_PAGE, spread_page) 2163TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 2164 2165TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 2166TASK_PFA_SET(SPREAD_SLAB, spread_slab) 2167TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 2168 2169/* 2170 * task->jobctl flags 2171 */ 2172#define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 2173 2174#define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 2175#define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 2176#define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 2177#define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 2178#define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 2179#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 2180#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 2181 2182#define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT) 2183#define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT) 2184#define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT) 2185#define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT) 2186#define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT) 2187#define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT) 2188#define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT) 2189 2190#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 2191#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 2192 2193extern bool task_set_jobctl_pending(struct task_struct *task, 2194 unsigned long mask); 2195extern void task_clear_jobctl_trapping(struct task_struct *task); 2196extern void task_clear_jobctl_pending(struct task_struct *task, 2197 unsigned long mask); 2198 2199static inline void rcu_copy_process(struct task_struct *p) 2200{ 2201#ifdef CONFIG_PREEMPT_RCU 2202 p->rcu_read_lock_nesting = 0; 2203 p->rcu_read_unlock_special.s = 0; 2204 p->rcu_blocked_node = NULL; 2205 INIT_LIST_HEAD(&p->rcu_node_entry); 2206#endif /* #ifdef CONFIG_PREEMPT_RCU */ 2207#ifdef CONFIG_TASKS_RCU 2208 p->rcu_tasks_holdout = false; 2209 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); 2210 p->rcu_tasks_idle_cpu = -1; 2211#endif /* #ifdef CONFIG_TASKS_RCU */ 2212} 2213 2214static inline void tsk_restore_flags(struct task_struct *task, 2215 unsigned long orig_flags, unsigned long flags) 2216{ 2217 task->flags &= ~flags; 2218 task->flags |= orig_flags & flags; 2219} 2220 2221extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, 2222 const struct cpumask *trial); 2223extern int task_can_attach(struct task_struct *p, 2224 const struct cpumask *cs_cpus_allowed); 2225#ifdef CONFIG_SMP 2226extern void do_set_cpus_allowed(struct task_struct *p, 2227 const struct cpumask *new_mask); 2228 2229extern int set_cpus_allowed_ptr(struct task_struct *p, 2230 const struct cpumask *new_mask); 2231#else 2232static inline void do_set_cpus_allowed(struct task_struct *p, 2233 const struct cpumask *new_mask) 2234{ 2235} 2236static inline int set_cpus_allowed_ptr(struct task_struct *p, 2237 const struct cpumask *new_mask) 2238{ 2239 if (!cpumask_test_cpu(0, new_mask)) 2240 return -EINVAL; 2241 return 0; 2242} 2243#endif 2244 2245#ifdef CONFIG_NO_HZ_COMMON 2246void calc_load_enter_idle(void); 2247void calc_load_exit_idle(void); 2248#else 2249static inline void calc_load_enter_idle(void) { } 2250static inline void calc_load_exit_idle(void) { } 2251#endif /* CONFIG_NO_HZ_COMMON */ 2252 2253/* 2254 * Do not use outside of architecture code which knows its limitations. 2255 * 2256 * sched_clock() has no promise of monotonicity or bounded drift between 2257 * CPUs, use (which you should not) requires disabling IRQs. 2258 * 2259 * Please use one of the three interfaces below. 2260 */ 2261extern unsigned long long notrace sched_clock(void); 2262/* 2263 * See the comment in kernel/sched/clock.c 2264 */ 2265extern u64 cpu_clock(int cpu); 2266extern u64 local_clock(void); 2267extern u64 running_clock(void); 2268extern u64 sched_clock_cpu(int cpu); 2269 2270 2271extern void sched_clock_init(void); 2272 2273#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2274static inline void sched_clock_tick(void) 2275{ 2276} 2277 2278static inline void sched_clock_idle_sleep_event(void) 2279{ 2280} 2281 2282static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 2283{ 2284} 2285#else 2286/* 2287 * Architectures can set this to 1 if they have specified 2288 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 2289 * but then during bootup it turns out that sched_clock() 2290 * is reliable after all: 2291 */ 2292extern int sched_clock_stable(void); 2293extern void set_sched_clock_stable(void); 2294extern void clear_sched_clock_stable(void); 2295 2296extern void sched_clock_tick(void); 2297extern void sched_clock_idle_sleep_event(void); 2298extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2299#endif 2300 2301#ifdef CONFIG_IRQ_TIME_ACCOUNTING 2302/* 2303 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 2304 * The reason for this explicit opt-in is not to have perf penalty with 2305 * slow sched_clocks. 2306 */ 2307extern void enable_sched_clock_irqtime(void); 2308extern void disable_sched_clock_irqtime(void); 2309#else 2310static inline void enable_sched_clock_irqtime(void) {} 2311static inline void disable_sched_clock_irqtime(void) {} 2312#endif 2313 2314extern unsigned long long 2315task_sched_runtime(struct task_struct *task); 2316 2317/* sched_exec is called by processes performing an exec */ 2318#ifdef CONFIG_SMP 2319extern void sched_exec(void); 2320#else 2321#define sched_exec() {} 2322#endif 2323 2324extern void sched_clock_idle_sleep_event(void); 2325extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2326 2327#ifdef CONFIG_HOTPLUG_CPU 2328extern void idle_task_exit(void); 2329#else 2330static inline void idle_task_exit(void) {} 2331#endif 2332 2333#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 2334extern void wake_up_nohz_cpu(int cpu); 2335#else 2336static inline void wake_up_nohz_cpu(int cpu) { } 2337#endif 2338 2339#ifdef CONFIG_NO_HZ_FULL 2340extern bool sched_can_stop_tick(void); 2341extern u64 scheduler_tick_max_deferment(void); 2342#else 2343static inline bool sched_can_stop_tick(void) { return false; } 2344#endif 2345 2346#ifdef CONFIG_SCHED_AUTOGROUP 2347extern void sched_autogroup_create_attach(struct task_struct *p); 2348extern void sched_autogroup_detach(struct task_struct *p); 2349extern void sched_autogroup_fork(struct signal_struct *sig); 2350extern void sched_autogroup_exit(struct signal_struct *sig); 2351#ifdef CONFIG_PROC_FS 2352extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2353extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2354#endif 2355#else 2356static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2357static inline void sched_autogroup_detach(struct task_struct *p) { } 2358static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2359static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2360#endif 2361 2362extern int yield_to(struct task_struct *p, bool preempt); 2363extern void set_user_nice(struct task_struct *p, long nice); 2364extern int task_prio(const struct task_struct *p); 2365/** 2366 * task_nice - return the nice value of a given task. 2367 * @p: the task in question. 2368 * 2369 * Return: The nice value [ -20 ... 0 ... 19 ]. 2370 */ 2371static inline int task_nice(const struct task_struct *p) 2372{ 2373 return PRIO_TO_NICE((p)->static_prio); 2374} 2375extern int can_nice(const struct task_struct *p, const int nice); 2376extern int task_curr(const struct task_struct *p); 2377extern int idle_cpu(int cpu); 2378extern int sched_setscheduler(struct task_struct *, int, 2379 const struct sched_param *); 2380extern int sched_setscheduler_nocheck(struct task_struct *, int, 2381 const struct sched_param *); 2382extern int sched_setattr(struct task_struct *, 2383 const struct sched_attr *); 2384extern struct task_struct *idle_task(int cpu); 2385/** 2386 * is_idle_task - is the specified task an idle task? 2387 * @p: the task in question. 2388 * 2389 * Return: 1 if @p is an idle task. 0 otherwise. 2390 */ 2391static inline bool is_idle_task(const struct task_struct *p) 2392{ 2393 return p->pid == 0; 2394} 2395extern struct task_struct *curr_task(int cpu); 2396extern void set_curr_task(int cpu, struct task_struct *p); 2397 2398void yield(void); 2399 2400union thread_union { 2401 struct thread_info thread_info; 2402 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2403}; 2404 2405#ifndef __HAVE_ARCH_KSTACK_END 2406static inline int kstack_end(void *addr) 2407{ 2408 /* Reliable end of stack detection: 2409 * Some APM bios versions misalign the stack 2410 */ 2411 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2412} 2413#endif 2414 2415extern union thread_union init_thread_union; 2416extern struct task_struct init_task; 2417 2418extern struct mm_struct init_mm; 2419 2420extern struct pid_namespace init_pid_ns; 2421 2422/* 2423 * find a task by one of its numerical ids 2424 * 2425 * find_task_by_pid_ns(): 2426 * finds a task by its pid in the specified namespace 2427 * find_task_by_vpid(): 2428 * finds a task by its virtual pid 2429 * 2430 * see also find_vpid() etc in include/linux/pid.h 2431 */ 2432 2433extern struct task_struct *find_task_by_vpid(pid_t nr); 2434extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2435 struct pid_namespace *ns); 2436 2437/* per-UID process charging. */ 2438extern struct user_struct * alloc_uid(kuid_t); 2439static inline struct user_struct *get_uid(struct user_struct *u) 2440{ 2441 atomic_inc(&u->__count); 2442 return u; 2443} 2444extern void free_uid(struct user_struct *); 2445 2446#include <asm/current.h> 2447 2448extern void xtime_update(unsigned long ticks); 2449 2450extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2451extern int wake_up_process(struct task_struct *tsk); 2452extern void wake_up_new_task(struct task_struct *tsk); 2453#ifdef CONFIG_SMP 2454 extern void kick_process(struct task_struct *tsk); 2455#else 2456 static inline void kick_process(struct task_struct *tsk) { } 2457#endif 2458extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 2459extern void sched_dead(struct task_struct *p); 2460 2461extern void proc_caches_init(void); 2462extern void flush_signals(struct task_struct *); 2463extern void ignore_signals(struct task_struct *); 2464extern void flush_signal_handlers(struct task_struct *, int force_default); 2465extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2466 2467static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2468{ 2469 unsigned long flags; 2470 int ret; 2471 2472 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2473 ret = dequeue_signal(tsk, mask, info); 2474 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2475 2476 return ret; 2477} 2478 2479extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2480 sigset_t *mask); 2481extern void unblock_all_signals(void); 2482extern void release_task(struct task_struct * p); 2483extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2484extern int force_sigsegv(int, struct task_struct *); 2485extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2486extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2487extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2488extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2489 const struct cred *, u32); 2490extern int kill_pgrp(struct pid *pid, int sig, int priv); 2491extern int kill_pid(struct pid *pid, int sig, int priv); 2492extern int kill_proc_info(int, struct siginfo *, pid_t); 2493extern __must_check bool do_notify_parent(struct task_struct *, int); 2494extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2495extern void force_sig(int, struct task_struct *); 2496extern int send_sig(int, struct task_struct *, int); 2497extern int zap_other_threads(struct task_struct *p); 2498extern struct sigqueue *sigqueue_alloc(void); 2499extern void sigqueue_free(struct sigqueue *); 2500extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2501extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2502 2503static inline void restore_saved_sigmask(void) 2504{ 2505 if (test_and_clear_restore_sigmask()) 2506 __set_current_blocked(&current->saved_sigmask); 2507} 2508 2509static inline sigset_t *sigmask_to_save(void) 2510{ 2511 sigset_t *res = &current->blocked; 2512 if (unlikely(test_restore_sigmask())) 2513 res = &current->saved_sigmask; 2514 return res; 2515} 2516 2517static inline int kill_cad_pid(int sig, int priv) 2518{ 2519 return kill_pid(cad_pid, sig, priv); 2520} 2521 2522/* These can be the second arg to send_sig_info/send_group_sig_info. */ 2523#define SEND_SIG_NOINFO ((struct siginfo *) 0) 2524#define SEND_SIG_PRIV ((struct siginfo *) 1) 2525#define SEND_SIG_FORCED ((struct siginfo *) 2) 2526 2527/* 2528 * True if we are on the alternate signal stack. 2529 */ 2530static inline int on_sig_stack(unsigned long sp) 2531{ 2532#ifdef CONFIG_STACK_GROWSUP 2533 return sp >= current->sas_ss_sp && 2534 sp - current->sas_ss_sp < current->sas_ss_size; 2535#else 2536 return sp > current->sas_ss_sp && 2537 sp - current->sas_ss_sp <= current->sas_ss_size; 2538#endif 2539} 2540 2541static inline int sas_ss_flags(unsigned long sp) 2542{ 2543 if (!current->sas_ss_size) 2544 return SS_DISABLE; 2545 2546 return on_sig_stack(sp) ? SS_ONSTACK : 0; 2547} 2548 2549static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2550{ 2551 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2552#ifdef CONFIG_STACK_GROWSUP 2553 return current->sas_ss_sp; 2554#else 2555 return current->sas_ss_sp + current->sas_ss_size; 2556#endif 2557 return sp; 2558} 2559 2560/* 2561 * Routines for handling mm_structs 2562 */ 2563extern struct mm_struct * mm_alloc(void); 2564 2565/* mmdrop drops the mm and the page tables */ 2566extern void __mmdrop(struct mm_struct *); 2567static inline void mmdrop(struct mm_struct * mm) 2568{ 2569 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2570 __mmdrop(mm); 2571} 2572 2573/* mmput gets rid of the mappings and all user-space */ 2574extern void mmput(struct mm_struct *); 2575/* Grab a reference to a task's mm, if it is not already going away */ 2576extern struct mm_struct *get_task_mm(struct task_struct *task); 2577/* 2578 * Grab a reference to a task's mm, if it is not already going away 2579 * and ptrace_may_access with the mode parameter passed to it 2580 * succeeds. 2581 */ 2582extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2583/* Remove the current tasks stale references to the old mm_struct */ 2584extern void mm_release(struct task_struct *, struct mm_struct *); 2585 2586#ifdef CONFIG_HAVE_COPY_THREAD_TLS 2587extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, 2588 struct task_struct *, unsigned long); 2589#else 2590extern int copy_thread(unsigned long, unsigned long, unsigned long, 2591 struct task_struct *); 2592 2593/* Architectures that haven't opted into copy_thread_tls get the tls argument 2594 * via pt_regs, so ignore the tls argument passed via C. */ 2595static inline int copy_thread_tls( 2596 unsigned long clone_flags, unsigned long sp, unsigned long arg, 2597 struct task_struct *p, unsigned long tls) 2598{ 2599 return copy_thread(clone_flags, sp, arg, p); 2600} 2601#endif 2602extern void flush_thread(void); 2603extern void exit_thread(void); 2604 2605extern void exit_files(struct task_struct *); 2606extern void __cleanup_sighand(struct sighand_struct *); 2607 2608extern void exit_itimers(struct signal_struct *); 2609extern void flush_itimer_signals(void); 2610 2611extern void do_group_exit(int); 2612 2613extern int do_execve(struct filename *, 2614 const char __user * const __user *, 2615 const char __user * const __user *); 2616extern int do_execveat(int, struct filename *, 2617 const char __user * const __user *, 2618 const char __user * const __user *, 2619 int); 2620extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long); 2621extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2622struct task_struct *fork_idle(int); 2623extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2624 2625extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 2626static inline void set_task_comm(struct task_struct *tsk, const char *from) 2627{ 2628 __set_task_comm(tsk, from, false); 2629} 2630extern char *get_task_comm(char *to, struct task_struct *tsk); 2631 2632#ifdef CONFIG_SMP 2633void scheduler_ipi(void); 2634extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2635#else 2636static inline void scheduler_ipi(void) { } 2637static inline unsigned long wait_task_inactive(struct task_struct *p, 2638 long match_state) 2639{ 2640 return 1; 2641} 2642#endif 2643 2644#define tasklist_empty() \ 2645 list_empty(&init_task.tasks) 2646 2647#define next_task(p) \ 2648 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2649 2650#define for_each_process(p) \ 2651 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2652 2653extern bool current_is_single_threaded(void); 2654 2655/* 2656 * Careful: do_each_thread/while_each_thread is a double loop so 2657 * 'break' will not work as expected - use goto instead. 2658 */ 2659#define do_each_thread(g, t) \ 2660 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2661 2662#define while_each_thread(g, t) \ 2663 while ((t = next_thread(t)) != g) 2664 2665#define __for_each_thread(signal, t) \ 2666 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) 2667 2668#define for_each_thread(p, t) \ 2669 __for_each_thread((p)->signal, t) 2670 2671/* Careful: this is a double loop, 'break' won't work as expected. */ 2672#define for_each_process_thread(p, t) \ 2673 for_each_process(p) for_each_thread(p, t) 2674 2675static inline int get_nr_threads(struct task_struct *tsk) 2676{ 2677 return tsk->signal->nr_threads; 2678} 2679 2680static inline bool thread_group_leader(struct task_struct *p) 2681{ 2682 return p->exit_signal >= 0; 2683} 2684 2685/* Do to the insanities of de_thread it is possible for a process 2686 * to have the pid of the thread group leader without actually being 2687 * the thread group leader. For iteration through the pids in proc 2688 * all we care about is that we have a task with the appropriate 2689 * pid, we don't actually care if we have the right task. 2690 */ 2691static inline bool has_group_leader_pid(struct task_struct *p) 2692{ 2693 return task_pid(p) == p->signal->leader_pid; 2694} 2695 2696static inline 2697bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 2698{ 2699 return p1->signal == p2->signal; 2700} 2701 2702static inline struct task_struct *next_thread(const struct task_struct *p) 2703{ 2704 return list_entry_rcu(p->thread_group.next, 2705 struct task_struct, thread_group); 2706} 2707 2708static inline int thread_group_empty(struct task_struct *p) 2709{ 2710 return list_empty(&p->thread_group); 2711} 2712 2713#define delay_group_leader(p) \ 2714 (thread_group_leader(p) && !thread_group_empty(p)) 2715 2716/* 2717 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2718 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2719 * pins the final release of task.io_context. Also protects ->cpuset and 2720 * ->cgroup.subsys[]. And ->vfork_done. 2721 * 2722 * Nests both inside and outside of read_lock(&tasklist_lock). 2723 * It must not be nested with write_lock_irq(&tasklist_lock), 2724 * neither inside nor outside. 2725 */ 2726static inline void task_lock(struct task_struct *p) 2727{ 2728 spin_lock(&p->alloc_lock); 2729} 2730 2731static inline void task_unlock(struct task_struct *p) 2732{ 2733 spin_unlock(&p->alloc_lock); 2734} 2735 2736extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2737 unsigned long *flags); 2738 2739static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2740 unsigned long *flags) 2741{ 2742 struct sighand_struct *ret; 2743 2744 ret = __lock_task_sighand(tsk, flags); 2745 (void)__cond_lock(&tsk->sighand->siglock, ret); 2746 return ret; 2747} 2748 2749static inline void unlock_task_sighand(struct task_struct *tsk, 2750 unsigned long *flags) 2751{ 2752 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2753} 2754 2755/** 2756 * threadgroup_change_begin - mark the beginning of changes to a threadgroup 2757 * @tsk: task causing the changes 2758 * 2759 * All operations which modify a threadgroup - a new thread joining the 2760 * group, death of a member thread (the assertion of PF_EXITING) and 2761 * exec(2) dethreading the process and replacing the leader - are wrapped 2762 * by threadgroup_change_{begin|end}(). This is to provide a place which 2763 * subsystems needing threadgroup stability can hook into for 2764 * synchronization. 2765 */ 2766static inline void threadgroup_change_begin(struct task_struct *tsk) 2767{ 2768 might_sleep(); 2769 cgroup_threadgroup_change_begin(tsk); 2770} 2771 2772/** 2773 * threadgroup_change_end - mark the end of changes to a threadgroup 2774 * @tsk: task causing the changes 2775 * 2776 * See threadgroup_change_begin(). 2777 */ 2778static inline void threadgroup_change_end(struct task_struct *tsk) 2779{ 2780 cgroup_threadgroup_change_end(tsk); 2781} 2782 2783#ifndef __HAVE_THREAD_FUNCTIONS 2784 2785#define task_thread_info(task) ((struct thread_info *)(task)->stack) 2786#define task_stack_page(task) ((task)->stack) 2787 2788static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2789{ 2790 *task_thread_info(p) = *task_thread_info(org); 2791 task_thread_info(p)->task = p; 2792} 2793 2794/* 2795 * Return the address of the last usable long on the stack. 2796 * 2797 * When the stack grows down, this is just above the thread 2798 * info struct. Going any lower will corrupt the threadinfo. 2799 * 2800 * When the stack grows up, this is the highest address. 2801 * Beyond that position, we corrupt data on the next page. 2802 */ 2803static inline unsigned long *end_of_stack(struct task_struct *p) 2804{ 2805#ifdef CONFIG_STACK_GROWSUP 2806 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1; 2807#else 2808 return (unsigned long *)(task_thread_info(p) + 1); 2809#endif 2810} 2811 2812#endif 2813#define task_stack_end_corrupted(task) \ 2814 (*(end_of_stack(task)) != STACK_END_MAGIC) 2815 2816static inline int object_is_on_stack(void *obj) 2817{ 2818 void *stack = task_stack_page(current); 2819 2820 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2821} 2822 2823extern void thread_info_cache_init(void); 2824 2825#ifdef CONFIG_DEBUG_STACK_USAGE 2826static inline unsigned long stack_not_used(struct task_struct *p) 2827{ 2828 unsigned long *n = end_of_stack(p); 2829 2830 do { /* Skip over canary */ 2831 n++; 2832 } while (!*n); 2833 2834 return (unsigned long)n - (unsigned long)end_of_stack(p); 2835} 2836#endif 2837extern void set_task_stack_end_magic(struct task_struct *tsk); 2838 2839/* set thread flags in other task's structures 2840 * - see asm/thread_info.h for TIF_xxxx flags available 2841 */ 2842static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2843{ 2844 set_ti_thread_flag(task_thread_info(tsk), flag); 2845} 2846 2847static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2848{ 2849 clear_ti_thread_flag(task_thread_info(tsk), flag); 2850} 2851 2852static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2853{ 2854 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2855} 2856 2857static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2858{ 2859 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2860} 2861 2862static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2863{ 2864 return test_ti_thread_flag(task_thread_info(tsk), flag); 2865} 2866 2867static inline void set_tsk_need_resched(struct task_struct *tsk) 2868{ 2869 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2870} 2871 2872static inline void clear_tsk_need_resched(struct task_struct *tsk) 2873{ 2874 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2875} 2876 2877static inline int test_tsk_need_resched(struct task_struct *tsk) 2878{ 2879 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2880} 2881 2882static inline int restart_syscall(void) 2883{ 2884 set_tsk_thread_flag(current, TIF_SIGPENDING); 2885 return -ERESTARTNOINTR; 2886} 2887 2888static inline int signal_pending(struct task_struct *p) 2889{ 2890 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2891} 2892 2893static inline int __fatal_signal_pending(struct task_struct *p) 2894{ 2895 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2896} 2897 2898static inline int fatal_signal_pending(struct task_struct *p) 2899{ 2900 return signal_pending(p) && __fatal_signal_pending(p); 2901} 2902 2903static inline int signal_pending_state(long state, struct task_struct *p) 2904{ 2905 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2906 return 0; 2907 if (!signal_pending(p)) 2908 return 0; 2909 2910 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2911} 2912 2913/* 2914 * cond_resched() and cond_resched_lock(): latency reduction via 2915 * explicit rescheduling in places that are safe. The return 2916 * value indicates whether a reschedule was done in fact. 2917 * cond_resched_lock() will drop the spinlock before scheduling, 2918 * cond_resched_softirq() will enable bhs before scheduling. 2919 */ 2920extern int _cond_resched(void); 2921 2922#define cond_resched() ({ \ 2923 ___might_sleep(__FILE__, __LINE__, 0); \ 2924 _cond_resched(); \ 2925}) 2926 2927extern int __cond_resched_lock(spinlock_t *lock); 2928 2929#define cond_resched_lock(lock) ({ \ 2930 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 2931 __cond_resched_lock(lock); \ 2932}) 2933 2934extern int __cond_resched_softirq(void); 2935 2936#define cond_resched_softirq() ({ \ 2937 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2938 __cond_resched_softirq(); \ 2939}) 2940 2941static inline void cond_resched_rcu(void) 2942{ 2943#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 2944 rcu_read_unlock(); 2945 cond_resched(); 2946 rcu_read_lock(); 2947#endif 2948} 2949 2950/* 2951 * Does a critical section need to be broken due to another 2952 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2953 * but a general need for low latency) 2954 */ 2955static inline int spin_needbreak(spinlock_t *lock) 2956{ 2957#ifdef CONFIG_PREEMPT 2958 return spin_is_contended(lock); 2959#else 2960 return 0; 2961#endif 2962} 2963 2964/* 2965 * Idle thread specific functions to determine the need_resched 2966 * polling state. 2967 */ 2968#ifdef TIF_POLLING_NRFLAG 2969static inline int tsk_is_polling(struct task_struct *p) 2970{ 2971 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 2972} 2973 2974static inline void __current_set_polling(void) 2975{ 2976 set_thread_flag(TIF_POLLING_NRFLAG); 2977} 2978 2979static inline bool __must_check current_set_polling_and_test(void) 2980{ 2981 __current_set_polling(); 2982 2983 /* 2984 * Polling state must be visible before we test NEED_RESCHED, 2985 * paired by resched_curr() 2986 */ 2987 smp_mb__after_atomic(); 2988 2989 return unlikely(tif_need_resched()); 2990} 2991 2992static inline void __current_clr_polling(void) 2993{ 2994 clear_thread_flag(TIF_POLLING_NRFLAG); 2995} 2996 2997static inline bool __must_check current_clr_polling_and_test(void) 2998{ 2999 __current_clr_polling(); 3000 3001 /* 3002 * Polling state must be visible before we test NEED_RESCHED, 3003 * paired by resched_curr() 3004 */ 3005 smp_mb__after_atomic(); 3006 3007 return unlikely(tif_need_resched()); 3008} 3009 3010#else 3011static inline int tsk_is_polling(struct task_struct *p) { return 0; } 3012static inline void __current_set_polling(void) { } 3013static inline void __current_clr_polling(void) { } 3014 3015static inline bool __must_check current_set_polling_and_test(void) 3016{ 3017 return unlikely(tif_need_resched()); 3018} 3019static inline bool __must_check current_clr_polling_and_test(void) 3020{ 3021 return unlikely(tif_need_resched()); 3022} 3023#endif 3024 3025static inline void current_clr_polling(void) 3026{ 3027 __current_clr_polling(); 3028 3029 /* 3030 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit. 3031 * Once the bit is cleared, we'll get IPIs with every new 3032 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also 3033 * fold. 3034 */ 3035 smp_mb(); /* paired with resched_curr() */ 3036 3037 preempt_fold_need_resched(); 3038} 3039 3040static __always_inline bool need_resched(void) 3041{ 3042 return unlikely(tif_need_resched()); 3043} 3044 3045/* 3046 * Thread group CPU time accounting. 3047 */ 3048void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 3049void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 3050 3051/* 3052 * Reevaluate whether the task has signals pending delivery. 3053 * Wake the task if so. 3054 * This is required every time the blocked sigset_t changes. 3055 * callers must hold sighand->siglock. 3056 */ 3057extern void recalc_sigpending_and_wake(struct task_struct *t); 3058extern void recalc_sigpending(void); 3059 3060extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 3061 3062static inline void signal_wake_up(struct task_struct *t, bool resume) 3063{ 3064 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 3065} 3066static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 3067{ 3068 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 3069} 3070 3071/* 3072 * Wrappers for p->thread_info->cpu access. No-op on UP. 3073 */ 3074#ifdef CONFIG_SMP 3075 3076static inline unsigned int task_cpu(const struct task_struct *p) 3077{ 3078 return task_thread_info(p)->cpu; 3079} 3080 3081static inline int task_node(const struct task_struct *p) 3082{ 3083 return cpu_to_node(task_cpu(p)); 3084} 3085 3086extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 3087 3088#else 3089 3090static inline unsigned int task_cpu(const struct task_struct *p) 3091{ 3092 return 0; 3093} 3094 3095static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 3096{ 3097} 3098 3099#endif /* CONFIG_SMP */ 3100 3101extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 3102extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 3103 3104#ifdef CONFIG_CGROUP_SCHED 3105extern struct task_group root_task_group; 3106#endif /* CONFIG_CGROUP_SCHED */ 3107 3108extern int task_can_switch_user(struct user_struct *up, 3109 struct task_struct *tsk); 3110 3111#ifdef CONFIG_TASK_XACCT 3112static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3113{ 3114 tsk->ioac.rchar += amt; 3115} 3116 3117static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3118{ 3119 tsk->ioac.wchar += amt; 3120} 3121 3122static inline void inc_syscr(struct task_struct *tsk) 3123{ 3124 tsk->ioac.syscr++; 3125} 3126 3127static inline void inc_syscw(struct task_struct *tsk) 3128{ 3129 tsk->ioac.syscw++; 3130} 3131#else 3132static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3133{ 3134} 3135 3136static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3137{ 3138} 3139 3140static inline void inc_syscr(struct task_struct *tsk) 3141{ 3142} 3143 3144static inline void inc_syscw(struct task_struct *tsk) 3145{ 3146} 3147#endif 3148 3149#ifndef TASK_SIZE_OF 3150#define TASK_SIZE_OF(tsk) TASK_SIZE 3151#endif 3152 3153#ifdef CONFIG_MEMCG 3154extern void mm_update_next_owner(struct mm_struct *mm); 3155#else 3156static inline void mm_update_next_owner(struct mm_struct *mm) 3157{ 3158} 3159#endif /* CONFIG_MEMCG */ 3160 3161static inline unsigned long task_rlimit(const struct task_struct *tsk, 3162 unsigned int limit) 3163{ 3164 return READ_ONCE(tsk->signal->rlim[limit].rlim_cur); 3165} 3166 3167static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 3168 unsigned int limit) 3169{ 3170 return READ_ONCE(tsk->signal->rlim[limit].rlim_max); 3171} 3172 3173static inline unsigned long rlimit(unsigned int limit) 3174{ 3175 return task_rlimit(current, limit); 3176} 3177 3178static inline unsigned long rlimit_max(unsigned int limit) 3179{ 3180 return task_rlimit_max(current, limit); 3181} 3182 3183#endif