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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_mask.h> 29 30#include <asm/page.h> 31#include <asm/ptrace.h> 32#include <linux/cputime.h> 33 34#include <linux/smp.h> 35#include <linux/sem.h> 36#include <linux/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 62#include <asm/processor.h> 63 64#define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */ 65 66/* 67 * Extended scheduling parameters data structure. 68 * 69 * This is needed because the original struct sched_param can not be 70 * altered without introducing ABI issues with legacy applications 71 * (e.g., in sched_getparam()). 72 * 73 * However, the possibility of specifying more than just a priority for 74 * the tasks may be useful for a wide variety of application fields, e.g., 75 * multimedia, streaming, automation and control, and many others. 76 * 77 * This variant (sched_attr) is meant at describing a so-called 78 * sporadic time-constrained task. In such model a task is specified by: 79 * - the activation period or minimum instance inter-arrival time; 80 * - the maximum (or average, depending on the actual scheduling 81 * discipline) computation time of all instances, a.k.a. runtime; 82 * - the deadline (relative to the actual activation time) of each 83 * instance. 84 * Very briefly, a periodic (sporadic) task asks for the execution of 85 * some specific computation --which is typically called an instance-- 86 * (at most) every period. Moreover, each instance typically lasts no more 87 * than the runtime and must be completed by time instant t equal to 88 * the instance activation time + the deadline. 89 * 90 * This is reflected by the actual fields of the sched_attr structure: 91 * 92 * @size size of the structure, for fwd/bwd compat. 93 * 94 * @sched_policy task's scheduling policy 95 * @sched_flags for customizing the scheduler behaviour 96 * @sched_nice task's nice value (SCHED_NORMAL/BATCH) 97 * @sched_priority task's static priority (SCHED_FIFO/RR) 98 * @sched_deadline representative of the task's deadline 99 * @sched_runtime representative of the task's runtime 100 * @sched_period representative of the task's period 101 * 102 * Given this task model, there are a multiplicity of scheduling algorithms 103 * and policies, that can be used to ensure all the tasks will make their 104 * timing constraints. 105 * 106 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the 107 * only user of this new interface. More information about the algorithm 108 * available in the scheduling class file or in Documentation/. 109 */ 110struct sched_attr { 111 u32 size; 112 113 u32 sched_policy; 114 u64 sched_flags; 115 116 /* SCHED_NORMAL, SCHED_BATCH */ 117 s32 sched_nice; 118 119 /* SCHED_FIFO, SCHED_RR */ 120 u32 sched_priority; 121 122 /* SCHED_DEADLINE */ 123 u64 sched_runtime; 124 u64 sched_deadline; 125 u64 sched_period; 126}; 127 128struct exec_domain; 129struct futex_pi_state; 130struct robust_list_head; 131struct bio_list; 132struct fs_struct; 133struct perf_event_context; 134struct blk_plug; 135struct filename; 136 137#define VMACACHE_BITS 2 138#define VMACACHE_SIZE (1U << VMACACHE_BITS) 139#define VMACACHE_MASK (VMACACHE_SIZE - 1) 140 141/* 142 * These are the constant used to fake the fixed-point load-average 143 * counting. Some notes: 144 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 145 * a load-average precision of 10 bits integer + 11 bits fractional 146 * - if you want to count load-averages more often, you need more 147 * precision, or rounding will get you. With 2-second counting freq, 148 * the EXP_n values would be 1981, 2034 and 2043 if still using only 149 * 11 bit fractions. 150 */ 151extern unsigned long avenrun[]; /* Load averages */ 152extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 153 154#define FSHIFT 11 /* nr of bits of precision */ 155#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 156#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 157#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 158#define EXP_5 2014 /* 1/exp(5sec/5min) */ 159#define EXP_15 2037 /* 1/exp(5sec/15min) */ 160 161#define CALC_LOAD(load,exp,n) \ 162 load *= exp; \ 163 load += n*(FIXED_1-exp); \ 164 load >>= FSHIFT; 165 166extern unsigned long total_forks; 167extern int nr_threads; 168DECLARE_PER_CPU(unsigned long, process_counts); 169extern int nr_processes(void); 170extern unsigned long nr_running(void); 171extern bool single_task_running(void); 172extern unsigned long nr_iowait(void); 173extern unsigned long nr_iowait_cpu(int cpu); 174extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load); 175 176extern void calc_global_load(unsigned long ticks); 177extern void update_cpu_load_nohz(void); 178 179extern unsigned long get_parent_ip(unsigned long addr); 180 181extern void dump_cpu_task(int cpu); 182 183struct seq_file; 184struct cfs_rq; 185struct task_group; 186#ifdef CONFIG_SCHED_DEBUG 187extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 188extern void proc_sched_set_task(struct task_struct *p); 189extern void 190print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 191#endif 192 193/* 194 * Task state bitmask. NOTE! These bits are also 195 * encoded in fs/proc/array.c: get_task_state(). 196 * 197 * We have two separate sets of flags: task->state 198 * is about runnability, while task->exit_state are 199 * about the task exiting. Confusing, but this way 200 * modifying one set can't modify the other one by 201 * mistake. 202 */ 203#define TASK_RUNNING 0 204#define TASK_INTERRUPTIBLE 1 205#define TASK_UNINTERRUPTIBLE 2 206#define __TASK_STOPPED 4 207#define __TASK_TRACED 8 208/* in tsk->exit_state */ 209#define EXIT_DEAD 16 210#define EXIT_ZOMBIE 32 211#define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 212/* in tsk->state again */ 213#define TASK_DEAD 64 214#define TASK_WAKEKILL 128 215#define TASK_WAKING 256 216#define TASK_PARKED 512 217#define TASK_STATE_MAX 1024 218 219#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWP" 220 221extern char ___assert_task_state[1 - 2*!!( 222 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 223 224/* Convenience macros for the sake of set_task_state */ 225#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 226#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 227#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 228 229/* Convenience macros for the sake of wake_up */ 230#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 231#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 232 233/* get_task_state() */ 234#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 235 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 236 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD) 237 238#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 239#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 240#define task_is_stopped_or_traced(task) \ 241 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 242#define task_contributes_to_load(task) \ 243 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 244 (task->flags & PF_FROZEN) == 0) 245 246#define __set_task_state(tsk, state_value) \ 247 do { (tsk)->state = (state_value); } while (0) 248#define set_task_state(tsk, state_value) \ 249 set_mb((tsk)->state, (state_value)) 250 251/* 252 * set_current_state() includes a barrier so that the write of current->state 253 * is correctly serialised wrt the caller's subsequent test of whether to 254 * actually sleep: 255 * 256 * set_current_state(TASK_UNINTERRUPTIBLE); 257 * if (do_i_need_to_sleep()) 258 * schedule(); 259 * 260 * If the caller does not need such serialisation then use __set_current_state() 261 */ 262#define __set_current_state(state_value) \ 263 do { current->state = (state_value); } while (0) 264#define set_current_state(state_value) \ 265 set_mb(current->state, (state_value)) 266 267/* Task command name length */ 268#define TASK_COMM_LEN 16 269 270#include <linux/spinlock.h> 271 272/* 273 * This serializes "schedule()" and also protects 274 * the run-queue from deletions/modifications (but 275 * _adding_ to the beginning of the run-queue has 276 * a separate lock). 277 */ 278extern rwlock_t tasklist_lock; 279extern spinlock_t mmlist_lock; 280 281struct task_struct; 282 283#ifdef CONFIG_PROVE_RCU 284extern int lockdep_tasklist_lock_is_held(void); 285#endif /* #ifdef CONFIG_PROVE_RCU */ 286 287extern void sched_init(void); 288extern void sched_init_smp(void); 289extern asmlinkage void schedule_tail(struct task_struct *prev); 290extern void init_idle(struct task_struct *idle, int cpu); 291extern void init_idle_bootup_task(struct task_struct *idle); 292 293extern int runqueue_is_locked(int cpu); 294 295#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 296extern void nohz_balance_enter_idle(int cpu); 297extern void set_cpu_sd_state_idle(void); 298extern int get_nohz_timer_target(int pinned); 299#else 300static inline void nohz_balance_enter_idle(int cpu) { } 301static inline void set_cpu_sd_state_idle(void) { } 302static inline int get_nohz_timer_target(int pinned) 303{ 304 return smp_processor_id(); 305} 306#endif 307 308/* 309 * Only dump TASK_* tasks. (0 for all tasks) 310 */ 311extern void show_state_filter(unsigned long state_filter); 312 313static inline void show_state(void) 314{ 315 show_state_filter(0); 316} 317 318extern void show_regs(struct pt_regs *); 319 320/* 321 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 322 * task), SP is the stack pointer of the first frame that should be shown in the back 323 * trace (or NULL if the entire call-chain of the task should be shown). 324 */ 325extern void show_stack(struct task_struct *task, unsigned long *sp); 326 327void io_schedule(void); 328long io_schedule_timeout(long timeout); 329 330extern void cpu_init (void); 331extern void trap_init(void); 332extern void update_process_times(int user); 333extern void scheduler_tick(void); 334 335extern void sched_show_task(struct task_struct *p); 336 337#ifdef CONFIG_LOCKUP_DETECTOR 338extern void touch_softlockup_watchdog(void); 339extern void touch_softlockup_watchdog_sync(void); 340extern void touch_all_softlockup_watchdogs(void); 341extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 342 void __user *buffer, 343 size_t *lenp, loff_t *ppos); 344extern unsigned int softlockup_panic; 345void lockup_detector_init(void); 346#else 347static inline void touch_softlockup_watchdog(void) 348{ 349} 350static inline void touch_softlockup_watchdog_sync(void) 351{ 352} 353static inline void touch_all_softlockup_watchdogs(void) 354{ 355} 356static inline void lockup_detector_init(void) 357{ 358} 359#endif 360 361#ifdef CONFIG_DETECT_HUNG_TASK 362void reset_hung_task_detector(void); 363#else 364static inline void reset_hung_task_detector(void) 365{ 366} 367#endif 368 369/* Attach to any functions which should be ignored in wchan output. */ 370#define __sched __attribute__((__section__(".sched.text"))) 371 372/* Linker adds these: start and end of __sched functions */ 373extern char __sched_text_start[], __sched_text_end[]; 374 375/* Is this address in the __sched functions? */ 376extern int in_sched_functions(unsigned long addr); 377 378#define MAX_SCHEDULE_TIMEOUT LONG_MAX 379extern signed long schedule_timeout(signed long timeout); 380extern signed long schedule_timeout_interruptible(signed long timeout); 381extern signed long schedule_timeout_killable(signed long timeout); 382extern signed long schedule_timeout_uninterruptible(signed long timeout); 383asmlinkage void schedule(void); 384extern void schedule_preempt_disabled(void); 385 386struct nsproxy; 387struct user_namespace; 388 389#ifdef CONFIG_MMU 390extern void arch_pick_mmap_layout(struct mm_struct *mm); 391extern unsigned long 392arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 393 unsigned long, unsigned long); 394extern unsigned long 395arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 396 unsigned long len, unsigned long pgoff, 397 unsigned long flags); 398#else 399static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 400#endif 401 402#define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 403#define SUID_DUMP_USER 1 /* Dump as user of process */ 404#define SUID_DUMP_ROOT 2 /* Dump as root */ 405 406/* mm flags */ 407 408/* for SUID_DUMP_* above */ 409#define MMF_DUMPABLE_BITS 2 410#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 411 412extern void set_dumpable(struct mm_struct *mm, int value); 413/* 414 * This returns the actual value of the suid_dumpable flag. For things 415 * that are using this for checking for privilege transitions, it must 416 * test against SUID_DUMP_USER rather than treating it as a boolean 417 * value. 418 */ 419static inline int __get_dumpable(unsigned long mm_flags) 420{ 421 return mm_flags & MMF_DUMPABLE_MASK; 422} 423 424static inline int get_dumpable(struct mm_struct *mm) 425{ 426 return __get_dumpable(mm->flags); 427} 428 429/* coredump filter bits */ 430#define MMF_DUMP_ANON_PRIVATE 2 431#define MMF_DUMP_ANON_SHARED 3 432#define MMF_DUMP_MAPPED_PRIVATE 4 433#define MMF_DUMP_MAPPED_SHARED 5 434#define MMF_DUMP_ELF_HEADERS 6 435#define MMF_DUMP_HUGETLB_PRIVATE 7 436#define MMF_DUMP_HUGETLB_SHARED 8 437 438#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 439#define MMF_DUMP_FILTER_BITS 7 440#define MMF_DUMP_FILTER_MASK \ 441 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 442#define MMF_DUMP_FILTER_DEFAULT \ 443 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 444 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 445 446#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 447# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 448#else 449# define MMF_DUMP_MASK_DEFAULT_ELF 0 450#endif 451 /* leave room for more dump flags */ 452#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 453#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 454#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 455 456#define MMF_HAS_UPROBES 19 /* has uprobes */ 457#define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 458 459#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 460 461struct sighand_struct { 462 atomic_t count; 463 struct k_sigaction action[_NSIG]; 464 spinlock_t siglock; 465 wait_queue_head_t signalfd_wqh; 466}; 467 468struct pacct_struct { 469 int ac_flag; 470 long ac_exitcode; 471 unsigned long ac_mem; 472 cputime_t ac_utime, ac_stime; 473 unsigned long ac_minflt, ac_majflt; 474}; 475 476struct cpu_itimer { 477 cputime_t expires; 478 cputime_t incr; 479 u32 error; 480 u32 incr_error; 481}; 482 483/** 484 * struct cputime - snaphsot of system and user cputime 485 * @utime: time spent in user mode 486 * @stime: time spent in system mode 487 * 488 * Gathers a generic snapshot of user and system time. 489 */ 490struct cputime { 491 cputime_t utime; 492 cputime_t stime; 493}; 494 495/** 496 * struct task_cputime - collected CPU time counts 497 * @utime: time spent in user mode, in &cputime_t units 498 * @stime: time spent in kernel mode, in &cputime_t units 499 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 500 * 501 * This is an extension of struct cputime that includes the total runtime 502 * spent by the task from the scheduler point of view. 503 * 504 * As a result, this structure groups together three kinds of CPU time 505 * that are tracked for threads and thread groups. Most things considering 506 * CPU time want to group these counts together and treat all three 507 * of them in parallel. 508 */ 509struct task_cputime { 510 cputime_t utime; 511 cputime_t stime; 512 unsigned long long sum_exec_runtime; 513}; 514/* Alternate field names when used to cache expirations. */ 515#define prof_exp stime 516#define virt_exp utime 517#define sched_exp sum_exec_runtime 518 519#define INIT_CPUTIME \ 520 (struct task_cputime) { \ 521 .utime = 0, \ 522 .stime = 0, \ 523 .sum_exec_runtime = 0, \ 524 } 525 526#ifdef CONFIG_PREEMPT_COUNT 527#define PREEMPT_DISABLED (1 + PREEMPT_ENABLED) 528#else 529#define PREEMPT_DISABLED PREEMPT_ENABLED 530#endif 531 532/* 533 * Disable preemption until the scheduler is running. 534 * Reset by start_kernel()->sched_init()->init_idle(). 535 * 536 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 537 * before the scheduler is active -- see should_resched(). 538 */ 539#define INIT_PREEMPT_COUNT (PREEMPT_DISABLED + PREEMPT_ACTIVE) 540 541/** 542 * struct thread_group_cputimer - thread group interval timer counts 543 * @cputime: thread group interval timers. 544 * @running: non-zero when there are timers running and 545 * @cputime receives updates. 546 * @lock: lock for fields in this struct. 547 * 548 * This structure contains the version of task_cputime, above, that is 549 * used for thread group CPU timer calculations. 550 */ 551struct thread_group_cputimer { 552 struct task_cputime cputime; 553 int running; 554 raw_spinlock_t lock; 555}; 556 557#include <linux/rwsem.h> 558struct autogroup; 559 560/* 561 * NOTE! "signal_struct" does not have its own 562 * locking, because a shared signal_struct always 563 * implies a shared sighand_struct, so locking 564 * sighand_struct is always a proper superset of 565 * the locking of signal_struct. 566 */ 567struct signal_struct { 568 atomic_t sigcnt; 569 atomic_t live; 570 int nr_threads; 571 struct list_head thread_head; 572 573 wait_queue_head_t wait_chldexit; /* for wait4() */ 574 575 /* current thread group signal load-balancing target: */ 576 struct task_struct *curr_target; 577 578 /* shared signal handling: */ 579 struct sigpending shared_pending; 580 581 /* thread group exit support */ 582 int group_exit_code; 583 /* overloaded: 584 * - notify group_exit_task when ->count is equal to notify_count 585 * - everyone except group_exit_task is stopped during signal delivery 586 * of fatal signals, group_exit_task processes the signal. 587 */ 588 int notify_count; 589 struct task_struct *group_exit_task; 590 591 /* thread group stop support, overloads group_exit_code too */ 592 int group_stop_count; 593 unsigned int flags; /* see SIGNAL_* flags below */ 594 595 /* 596 * PR_SET_CHILD_SUBREAPER marks a process, like a service 597 * manager, to re-parent orphan (double-forking) child processes 598 * to this process instead of 'init'. The service manager is 599 * able to receive SIGCHLD signals and is able to investigate 600 * the process until it calls wait(). All children of this 601 * process will inherit a flag if they should look for a 602 * child_subreaper process at exit. 603 */ 604 unsigned int is_child_subreaper:1; 605 unsigned int has_child_subreaper:1; 606 607 /* POSIX.1b Interval Timers */ 608 int posix_timer_id; 609 struct list_head posix_timers; 610 611 /* ITIMER_REAL timer for the process */ 612 struct hrtimer real_timer; 613 struct pid *leader_pid; 614 ktime_t it_real_incr; 615 616 /* 617 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 618 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 619 * values are defined to 0 and 1 respectively 620 */ 621 struct cpu_itimer it[2]; 622 623 /* 624 * Thread group totals for process CPU timers. 625 * See thread_group_cputimer(), et al, for details. 626 */ 627 struct thread_group_cputimer cputimer; 628 629 /* Earliest-expiration cache. */ 630 struct task_cputime cputime_expires; 631 632 struct list_head cpu_timers[3]; 633 634 struct pid *tty_old_pgrp; 635 636 /* boolean value for session group leader */ 637 int leader; 638 639 struct tty_struct *tty; /* NULL if no tty */ 640 641#ifdef CONFIG_SCHED_AUTOGROUP 642 struct autogroup *autogroup; 643#endif 644 /* 645 * Cumulative resource counters for dead threads in the group, 646 * and for reaped dead child processes forked by this group. 647 * Live threads maintain their own counters and add to these 648 * in __exit_signal, except for the group leader. 649 */ 650 seqlock_t stats_lock; 651 cputime_t utime, stime, cutime, cstime; 652 cputime_t gtime; 653 cputime_t cgtime; 654#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 655 struct cputime prev_cputime; 656#endif 657 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 658 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 659 unsigned long inblock, oublock, cinblock, coublock; 660 unsigned long maxrss, cmaxrss; 661 struct task_io_accounting ioac; 662 663 /* 664 * Cumulative ns of schedule CPU time fo dead threads in the 665 * group, not including a zombie group leader, (This only differs 666 * from jiffies_to_ns(utime + stime) if sched_clock uses something 667 * other than jiffies.) 668 */ 669 unsigned long long sum_sched_runtime; 670 671 /* 672 * We don't bother to synchronize most readers of this at all, 673 * because there is no reader checking a limit that actually needs 674 * to get both rlim_cur and rlim_max atomically, and either one 675 * alone is a single word that can safely be read normally. 676 * getrlimit/setrlimit use task_lock(current->group_leader) to 677 * protect this instead of the siglock, because they really 678 * have no need to disable irqs. 679 */ 680 struct rlimit rlim[RLIM_NLIMITS]; 681 682#ifdef CONFIG_BSD_PROCESS_ACCT 683 struct pacct_struct pacct; /* per-process accounting information */ 684#endif 685#ifdef CONFIG_TASKSTATS 686 struct taskstats *stats; 687#endif 688#ifdef CONFIG_AUDIT 689 unsigned audit_tty; 690 unsigned audit_tty_log_passwd; 691 struct tty_audit_buf *tty_audit_buf; 692#endif 693#ifdef CONFIG_CGROUPS 694 /* 695 * group_rwsem prevents new tasks from entering the threadgroup and 696 * member tasks from exiting,a more specifically, setting of 697 * PF_EXITING. fork and exit paths are protected with this rwsem 698 * using threadgroup_change_begin/end(). Users which require 699 * threadgroup to remain stable should use threadgroup_[un]lock() 700 * which also takes care of exec path. Currently, cgroup is the 701 * only user. 702 */ 703 struct rw_semaphore group_rwsem; 704#endif 705 706 oom_flags_t oom_flags; 707 short oom_score_adj; /* OOM kill score adjustment */ 708 short oom_score_adj_min; /* OOM kill score adjustment min value. 709 * Only settable by CAP_SYS_RESOURCE. */ 710 711 struct mutex cred_guard_mutex; /* guard against foreign influences on 712 * credential calculations 713 * (notably. ptrace) */ 714}; 715 716/* 717 * Bits in flags field of signal_struct. 718 */ 719#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 720#define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 721#define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 722#define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 723/* 724 * Pending notifications to parent. 725 */ 726#define SIGNAL_CLD_STOPPED 0x00000010 727#define SIGNAL_CLD_CONTINUED 0x00000020 728#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 729 730#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 731 732/* If true, all threads except ->group_exit_task have pending SIGKILL */ 733static inline int signal_group_exit(const struct signal_struct *sig) 734{ 735 return (sig->flags & SIGNAL_GROUP_EXIT) || 736 (sig->group_exit_task != NULL); 737} 738 739/* 740 * Some day this will be a full-fledged user tracking system.. 741 */ 742struct user_struct { 743 atomic_t __count; /* reference count */ 744 atomic_t processes; /* How many processes does this user have? */ 745 atomic_t sigpending; /* How many pending signals does this user have? */ 746#ifdef CONFIG_INOTIFY_USER 747 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 748 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 749#endif 750#ifdef CONFIG_FANOTIFY 751 atomic_t fanotify_listeners; 752#endif 753#ifdef CONFIG_EPOLL 754 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 755#endif 756#ifdef CONFIG_POSIX_MQUEUE 757 /* protected by mq_lock */ 758 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 759#endif 760 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 761 762#ifdef CONFIG_KEYS 763 struct key *uid_keyring; /* UID specific keyring */ 764 struct key *session_keyring; /* UID's default session keyring */ 765#endif 766 767 /* Hash table maintenance information */ 768 struct hlist_node uidhash_node; 769 kuid_t uid; 770 771#ifdef CONFIG_PERF_EVENTS 772 atomic_long_t locked_vm; 773#endif 774}; 775 776extern int uids_sysfs_init(void); 777 778extern struct user_struct *find_user(kuid_t); 779 780extern struct user_struct root_user; 781#define INIT_USER (&root_user) 782 783 784struct backing_dev_info; 785struct reclaim_state; 786 787#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 788struct sched_info { 789 /* cumulative counters */ 790 unsigned long pcount; /* # of times run on this cpu */ 791 unsigned long long run_delay; /* time spent waiting on a runqueue */ 792 793 /* timestamps */ 794 unsigned long long last_arrival,/* when we last ran on a cpu */ 795 last_queued; /* when we were last queued to run */ 796}; 797#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ 798 799#ifdef CONFIG_TASK_DELAY_ACCT 800struct task_delay_info { 801 spinlock_t lock; 802 unsigned int flags; /* Private per-task flags */ 803 804 /* For each stat XXX, add following, aligned appropriately 805 * 806 * struct timespec XXX_start, XXX_end; 807 * u64 XXX_delay; 808 * u32 XXX_count; 809 * 810 * Atomicity of updates to XXX_delay, XXX_count protected by 811 * single lock above (split into XXX_lock if contention is an issue). 812 */ 813 814 /* 815 * XXX_count is incremented on every XXX operation, the delay 816 * associated with the operation is added to XXX_delay. 817 * XXX_delay contains the accumulated delay time in nanoseconds. 818 */ 819 u64 blkio_start; /* Shared by blkio, swapin */ 820 u64 blkio_delay; /* wait for sync block io completion */ 821 u64 swapin_delay; /* wait for swapin block io completion */ 822 u32 blkio_count; /* total count of the number of sync block */ 823 /* io operations performed */ 824 u32 swapin_count; /* total count of the number of swapin block */ 825 /* io operations performed */ 826 827 u64 freepages_start; 828 u64 freepages_delay; /* wait for memory reclaim */ 829 u32 freepages_count; /* total count of memory reclaim */ 830}; 831#endif /* CONFIG_TASK_DELAY_ACCT */ 832 833static inline int sched_info_on(void) 834{ 835#ifdef CONFIG_SCHEDSTATS 836 return 1; 837#elif defined(CONFIG_TASK_DELAY_ACCT) 838 extern int delayacct_on; 839 return delayacct_on; 840#else 841 return 0; 842#endif 843} 844 845enum cpu_idle_type { 846 CPU_IDLE, 847 CPU_NOT_IDLE, 848 CPU_NEWLY_IDLE, 849 CPU_MAX_IDLE_TYPES 850}; 851 852/* 853 * Increase resolution of cpu_capacity calculations 854 */ 855#define SCHED_CAPACITY_SHIFT 10 856#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 857 858/* 859 * sched-domains (multiprocessor balancing) declarations: 860 */ 861#ifdef CONFIG_SMP 862#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 863#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 864#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 865#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 866#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 867#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 868#define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu power */ 869#define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ 870#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 871#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 872#define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 873#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 874#define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 875#define SD_NUMA 0x4000 /* cross-node balancing */ 876 877#ifdef CONFIG_SCHED_SMT 878static inline int cpu_smt_flags(void) 879{ 880 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; 881} 882#endif 883 884#ifdef CONFIG_SCHED_MC 885static inline int cpu_core_flags(void) 886{ 887 return SD_SHARE_PKG_RESOURCES; 888} 889#endif 890 891#ifdef CONFIG_NUMA 892static inline int cpu_numa_flags(void) 893{ 894 return SD_NUMA; 895} 896#endif 897 898struct sched_domain_attr { 899 int relax_domain_level; 900}; 901 902#define SD_ATTR_INIT (struct sched_domain_attr) { \ 903 .relax_domain_level = -1, \ 904} 905 906extern int sched_domain_level_max; 907 908struct sched_group; 909 910struct sched_domain { 911 /* These fields must be setup */ 912 struct sched_domain *parent; /* top domain must be null terminated */ 913 struct sched_domain *child; /* bottom domain must be null terminated */ 914 struct sched_group *groups; /* the balancing groups of the domain */ 915 unsigned long min_interval; /* Minimum balance interval ms */ 916 unsigned long max_interval; /* Maximum balance interval ms */ 917 unsigned int busy_factor; /* less balancing by factor if busy */ 918 unsigned int imbalance_pct; /* No balance until over watermark */ 919 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 920 unsigned int busy_idx; 921 unsigned int idle_idx; 922 unsigned int newidle_idx; 923 unsigned int wake_idx; 924 unsigned int forkexec_idx; 925 unsigned int smt_gain; 926 927 int nohz_idle; /* NOHZ IDLE status */ 928 int flags; /* See SD_* */ 929 int level; 930 931 /* Runtime fields. */ 932 unsigned long last_balance; /* init to jiffies. units in jiffies */ 933 unsigned int balance_interval; /* initialise to 1. units in ms. */ 934 unsigned int nr_balance_failed; /* initialise to 0 */ 935 936 /* idle_balance() stats */ 937 u64 max_newidle_lb_cost; 938 unsigned long next_decay_max_lb_cost; 939 940#ifdef CONFIG_SCHEDSTATS 941 /* load_balance() stats */ 942 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 943 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 944 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 945 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 946 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 947 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 948 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 949 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 950 951 /* Active load balancing */ 952 unsigned int alb_count; 953 unsigned int alb_failed; 954 unsigned int alb_pushed; 955 956 /* SD_BALANCE_EXEC stats */ 957 unsigned int sbe_count; 958 unsigned int sbe_balanced; 959 unsigned int sbe_pushed; 960 961 /* SD_BALANCE_FORK stats */ 962 unsigned int sbf_count; 963 unsigned int sbf_balanced; 964 unsigned int sbf_pushed; 965 966 /* try_to_wake_up() stats */ 967 unsigned int ttwu_wake_remote; 968 unsigned int ttwu_move_affine; 969 unsigned int ttwu_move_balance; 970#endif 971#ifdef CONFIG_SCHED_DEBUG 972 char *name; 973#endif 974 union { 975 void *private; /* used during construction */ 976 struct rcu_head rcu; /* used during destruction */ 977 }; 978 979 unsigned int span_weight; 980 /* 981 * Span of all CPUs in this domain. 982 * 983 * NOTE: this field is variable length. (Allocated dynamically 984 * by attaching extra space to the end of the structure, 985 * depending on how many CPUs the kernel has booted up with) 986 */ 987 unsigned long span[0]; 988}; 989 990static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 991{ 992 return to_cpumask(sd->span); 993} 994 995extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 996 struct sched_domain_attr *dattr_new); 997 998/* Allocate an array of sched domains, for partition_sched_domains(). */ 999cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 1000void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 1001 1002bool cpus_share_cache(int this_cpu, int that_cpu); 1003 1004typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); 1005typedef int (*sched_domain_flags_f)(void); 1006 1007#define SDTL_OVERLAP 0x01 1008 1009struct sd_data { 1010 struct sched_domain **__percpu sd; 1011 struct sched_group **__percpu sg; 1012 struct sched_group_capacity **__percpu sgc; 1013}; 1014 1015struct sched_domain_topology_level { 1016 sched_domain_mask_f mask; 1017 sched_domain_flags_f sd_flags; 1018 int flags; 1019 int numa_level; 1020 struct sd_data data; 1021#ifdef CONFIG_SCHED_DEBUG 1022 char *name; 1023#endif 1024}; 1025 1026extern struct sched_domain_topology_level *sched_domain_topology; 1027 1028extern void set_sched_topology(struct sched_domain_topology_level *tl); 1029extern void wake_up_if_idle(int cpu); 1030 1031#ifdef CONFIG_SCHED_DEBUG 1032# define SD_INIT_NAME(type) .name = #type 1033#else 1034# define SD_INIT_NAME(type) 1035#endif 1036 1037#else /* CONFIG_SMP */ 1038 1039struct sched_domain_attr; 1040 1041static inline void 1042partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1043 struct sched_domain_attr *dattr_new) 1044{ 1045} 1046 1047static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1048{ 1049 return true; 1050} 1051 1052#endif /* !CONFIG_SMP */ 1053 1054 1055struct io_context; /* See blkdev.h */ 1056 1057 1058#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1059extern void prefetch_stack(struct task_struct *t); 1060#else 1061static inline void prefetch_stack(struct task_struct *t) { } 1062#endif 1063 1064struct audit_context; /* See audit.c */ 1065struct mempolicy; 1066struct pipe_inode_info; 1067struct uts_namespace; 1068 1069struct load_weight { 1070 unsigned long weight; 1071 u32 inv_weight; 1072}; 1073 1074struct sched_avg { 1075 /* 1076 * These sums represent an infinite geometric series and so are bound 1077 * above by 1024/(1-y). Thus we only need a u32 to store them for all 1078 * choices of y < 1-2^(-32)*1024. 1079 */ 1080 u32 runnable_avg_sum, runnable_avg_period; 1081 u64 last_runnable_update; 1082 s64 decay_count; 1083 unsigned long load_avg_contrib; 1084}; 1085 1086#ifdef CONFIG_SCHEDSTATS 1087struct sched_statistics { 1088 u64 wait_start; 1089 u64 wait_max; 1090 u64 wait_count; 1091 u64 wait_sum; 1092 u64 iowait_count; 1093 u64 iowait_sum; 1094 1095 u64 sleep_start; 1096 u64 sleep_max; 1097 s64 sum_sleep_runtime; 1098 1099 u64 block_start; 1100 u64 block_max; 1101 u64 exec_max; 1102 u64 slice_max; 1103 1104 u64 nr_migrations_cold; 1105 u64 nr_failed_migrations_affine; 1106 u64 nr_failed_migrations_running; 1107 u64 nr_failed_migrations_hot; 1108 u64 nr_forced_migrations; 1109 1110 u64 nr_wakeups; 1111 u64 nr_wakeups_sync; 1112 u64 nr_wakeups_migrate; 1113 u64 nr_wakeups_local; 1114 u64 nr_wakeups_remote; 1115 u64 nr_wakeups_affine; 1116 u64 nr_wakeups_affine_attempts; 1117 u64 nr_wakeups_passive; 1118 u64 nr_wakeups_idle; 1119}; 1120#endif 1121 1122struct sched_entity { 1123 struct load_weight load; /* for load-balancing */ 1124 struct rb_node run_node; 1125 struct list_head group_node; 1126 unsigned int on_rq; 1127 1128 u64 exec_start; 1129 u64 sum_exec_runtime; 1130 u64 vruntime; 1131 u64 prev_sum_exec_runtime; 1132 1133 u64 nr_migrations; 1134 1135#ifdef CONFIG_SCHEDSTATS 1136 struct sched_statistics statistics; 1137#endif 1138 1139#ifdef CONFIG_FAIR_GROUP_SCHED 1140 int depth; 1141 struct sched_entity *parent; 1142 /* rq on which this entity is (to be) queued: */ 1143 struct cfs_rq *cfs_rq; 1144 /* rq "owned" by this entity/group: */ 1145 struct cfs_rq *my_q; 1146#endif 1147 1148#ifdef CONFIG_SMP 1149 /* Per-entity load-tracking */ 1150 struct sched_avg avg; 1151#endif 1152}; 1153 1154struct sched_rt_entity { 1155 struct list_head run_list; 1156 unsigned long timeout; 1157 unsigned long watchdog_stamp; 1158 unsigned int time_slice; 1159 1160 struct sched_rt_entity *back; 1161#ifdef CONFIG_RT_GROUP_SCHED 1162 struct sched_rt_entity *parent; 1163 /* rq on which this entity is (to be) queued: */ 1164 struct rt_rq *rt_rq; 1165 /* rq "owned" by this entity/group: */ 1166 struct rt_rq *my_q; 1167#endif 1168}; 1169 1170struct sched_dl_entity { 1171 struct rb_node rb_node; 1172 1173 /* 1174 * Original scheduling parameters. Copied here from sched_attr 1175 * during sched_setattr(), they will remain the same until 1176 * the next sched_setattr(). 1177 */ 1178 u64 dl_runtime; /* maximum runtime for each instance */ 1179 u64 dl_deadline; /* relative deadline of each instance */ 1180 u64 dl_period; /* separation of two instances (period) */ 1181 u64 dl_bw; /* dl_runtime / dl_deadline */ 1182 1183 /* 1184 * Actual scheduling parameters. Initialized with the values above, 1185 * they are continously updated during task execution. Note that 1186 * the remaining runtime could be < 0 in case we are in overrun. 1187 */ 1188 s64 runtime; /* remaining runtime for this instance */ 1189 u64 deadline; /* absolute deadline for this instance */ 1190 unsigned int flags; /* specifying the scheduler behaviour */ 1191 1192 /* 1193 * Some bool flags: 1194 * 1195 * @dl_throttled tells if we exhausted the runtime. If so, the 1196 * task has to wait for a replenishment to be performed at the 1197 * next firing of dl_timer. 1198 * 1199 * @dl_new tells if a new instance arrived. If so we must 1200 * start executing it with full runtime and reset its absolute 1201 * deadline; 1202 * 1203 * @dl_boosted tells if we are boosted due to DI. If so we are 1204 * outside bandwidth enforcement mechanism (but only until we 1205 * exit the critical section); 1206 * 1207 * @dl_yielded tells if task gave up the cpu before consuming 1208 * all its available runtime during the last job. 1209 */ 1210 int dl_throttled, dl_new, dl_boosted, dl_yielded; 1211 1212 /* 1213 * Bandwidth enforcement timer. Each -deadline task has its 1214 * own bandwidth to be enforced, thus we need one timer per task. 1215 */ 1216 struct hrtimer dl_timer; 1217}; 1218 1219union rcu_special { 1220 struct { 1221 bool blocked; 1222 bool need_qs; 1223 } b; 1224 short s; 1225}; 1226struct rcu_node; 1227 1228enum perf_event_task_context { 1229 perf_invalid_context = -1, 1230 perf_hw_context = 0, 1231 perf_sw_context, 1232 perf_nr_task_contexts, 1233}; 1234 1235struct task_struct { 1236 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1237 void *stack; 1238 atomic_t usage; 1239 unsigned int flags; /* per process flags, defined below */ 1240 unsigned int ptrace; 1241 1242#ifdef CONFIG_SMP 1243 struct llist_node wake_entry; 1244 int on_cpu; 1245 struct task_struct *last_wakee; 1246 unsigned long wakee_flips; 1247 unsigned long wakee_flip_decay_ts; 1248 1249 int wake_cpu; 1250#endif 1251 int on_rq; 1252 1253 int prio, static_prio, normal_prio; 1254 unsigned int rt_priority; 1255 const struct sched_class *sched_class; 1256 struct sched_entity se; 1257 struct sched_rt_entity rt; 1258#ifdef CONFIG_CGROUP_SCHED 1259 struct task_group *sched_task_group; 1260#endif 1261 struct sched_dl_entity dl; 1262 1263#ifdef CONFIG_PREEMPT_NOTIFIERS 1264 /* list of struct preempt_notifier: */ 1265 struct hlist_head preempt_notifiers; 1266#endif 1267 1268#ifdef CONFIG_BLK_DEV_IO_TRACE 1269 unsigned int btrace_seq; 1270#endif 1271 1272 unsigned int policy; 1273 int nr_cpus_allowed; 1274 cpumask_t cpus_allowed; 1275 1276#ifdef CONFIG_PREEMPT_RCU 1277 int rcu_read_lock_nesting; 1278 union rcu_special rcu_read_unlock_special; 1279 struct list_head rcu_node_entry; 1280#endif /* #ifdef CONFIG_PREEMPT_RCU */ 1281#ifdef CONFIG_TREE_PREEMPT_RCU 1282 struct rcu_node *rcu_blocked_node; 1283#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1284#ifdef CONFIG_TASKS_RCU 1285 unsigned long rcu_tasks_nvcsw; 1286 bool rcu_tasks_holdout; 1287 struct list_head rcu_tasks_holdout_list; 1288 int rcu_tasks_idle_cpu; 1289#endif /* #ifdef CONFIG_TASKS_RCU */ 1290 1291#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 1292 struct sched_info sched_info; 1293#endif 1294 1295 struct list_head tasks; 1296#ifdef CONFIG_SMP 1297 struct plist_node pushable_tasks; 1298 struct rb_node pushable_dl_tasks; 1299#endif 1300 1301 struct mm_struct *mm, *active_mm; 1302#ifdef CONFIG_COMPAT_BRK 1303 unsigned brk_randomized:1; 1304#endif 1305 /* per-thread vma caching */ 1306 u32 vmacache_seqnum; 1307 struct vm_area_struct *vmacache[VMACACHE_SIZE]; 1308#if defined(SPLIT_RSS_COUNTING) 1309 struct task_rss_stat rss_stat; 1310#endif 1311/* task state */ 1312 int exit_state; 1313 int exit_code, exit_signal; 1314 int pdeath_signal; /* The signal sent when the parent dies */ 1315 unsigned int jobctl; /* JOBCTL_*, siglock protected */ 1316 1317 /* Used for emulating ABI behavior of previous Linux versions */ 1318 unsigned int personality; 1319 1320 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1321 * execve */ 1322 unsigned in_iowait:1; 1323 1324 /* Revert to default priority/policy when forking */ 1325 unsigned sched_reset_on_fork:1; 1326 unsigned sched_contributes_to_load:1; 1327 1328 unsigned long atomic_flags; /* Flags needing atomic access. */ 1329 1330 pid_t pid; 1331 pid_t tgid; 1332 1333#ifdef CONFIG_CC_STACKPROTECTOR 1334 /* Canary value for the -fstack-protector gcc feature */ 1335 unsigned long stack_canary; 1336#endif 1337 /* 1338 * pointers to (original) parent process, youngest child, younger sibling, 1339 * older sibling, respectively. (p->father can be replaced with 1340 * p->real_parent->pid) 1341 */ 1342 struct task_struct __rcu *real_parent; /* real parent process */ 1343 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1344 /* 1345 * children/sibling forms the list of my natural children 1346 */ 1347 struct list_head children; /* list of my children */ 1348 struct list_head sibling; /* linkage in my parent's children list */ 1349 struct task_struct *group_leader; /* threadgroup leader */ 1350 1351 /* 1352 * ptraced is the list of tasks this task is using ptrace on. 1353 * This includes both natural children and PTRACE_ATTACH targets. 1354 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1355 */ 1356 struct list_head ptraced; 1357 struct list_head ptrace_entry; 1358 1359 /* PID/PID hash table linkage. */ 1360 struct pid_link pids[PIDTYPE_MAX]; 1361 struct list_head thread_group; 1362 struct list_head thread_node; 1363 1364 struct completion *vfork_done; /* for vfork() */ 1365 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1366 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1367 1368 cputime_t utime, stime, utimescaled, stimescaled; 1369 cputime_t gtime; 1370#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 1371 struct cputime prev_cputime; 1372#endif 1373#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1374 seqlock_t vtime_seqlock; 1375 unsigned long long vtime_snap; 1376 enum { 1377 VTIME_SLEEPING = 0, 1378 VTIME_USER, 1379 VTIME_SYS, 1380 } vtime_snap_whence; 1381#endif 1382 unsigned long nvcsw, nivcsw; /* context switch counts */ 1383 u64 start_time; /* monotonic time in nsec */ 1384 u64 real_start_time; /* boot based time in nsec */ 1385/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1386 unsigned long min_flt, maj_flt; 1387 1388 struct task_cputime cputime_expires; 1389 struct list_head cpu_timers[3]; 1390 1391/* process credentials */ 1392 const struct cred __rcu *real_cred; /* objective and real subjective task 1393 * credentials (COW) */ 1394 const struct cred __rcu *cred; /* effective (overridable) subjective task 1395 * credentials (COW) */ 1396 char comm[TASK_COMM_LEN]; /* executable name excluding path 1397 - access with [gs]et_task_comm (which lock 1398 it with task_lock()) 1399 - initialized normally by setup_new_exec */ 1400/* file system info */ 1401 int link_count, total_link_count; 1402#ifdef CONFIG_SYSVIPC 1403/* ipc stuff */ 1404 struct sysv_sem sysvsem; 1405 struct sysv_shm sysvshm; 1406#endif 1407#ifdef CONFIG_DETECT_HUNG_TASK 1408/* hung task detection */ 1409 unsigned long last_switch_count; 1410#endif 1411/* CPU-specific state of this task */ 1412 struct thread_struct thread; 1413/* filesystem information */ 1414 struct fs_struct *fs; 1415/* open file information */ 1416 struct files_struct *files; 1417/* namespaces */ 1418 struct nsproxy *nsproxy; 1419/* signal handlers */ 1420 struct signal_struct *signal; 1421 struct sighand_struct *sighand; 1422 1423 sigset_t blocked, real_blocked; 1424 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1425 struct sigpending pending; 1426 1427 unsigned long sas_ss_sp; 1428 size_t sas_ss_size; 1429 int (*notifier)(void *priv); 1430 void *notifier_data; 1431 sigset_t *notifier_mask; 1432 struct callback_head *task_works; 1433 1434 struct audit_context *audit_context; 1435#ifdef CONFIG_AUDITSYSCALL 1436 kuid_t loginuid; 1437 unsigned int sessionid; 1438#endif 1439 struct seccomp seccomp; 1440 1441/* Thread group tracking */ 1442 u32 parent_exec_id; 1443 u32 self_exec_id; 1444/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1445 * mempolicy */ 1446 spinlock_t alloc_lock; 1447 1448 /* Protection of the PI data structures: */ 1449 raw_spinlock_t pi_lock; 1450 1451#ifdef CONFIG_RT_MUTEXES 1452 /* PI waiters blocked on a rt_mutex held by this task */ 1453 struct rb_root pi_waiters; 1454 struct rb_node *pi_waiters_leftmost; 1455 /* Deadlock detection and priority inheritance handling */ 1456 struct rt_mutex_waiter *pi_blocked_on; 1457#endif 1458 1459#ifdef CONFIG_DEBUG_MUTEXES 1460 /* mutex deadlock detection */ 1461 struct mutex_waiter *blocked_on; 1462#endif 1463#ifdef CONFIG_TRACE_IRQFLAGS 1464 unsigned int irq_events; 1465 unsigned long hardirq_enable_ip; 1466 unsigned long hardirq_disable_ip; 1467 unsigned int hardirq_enable_event; 1468 unsigned int hardirq_disable_event; 1469 int hardirqs_enabled; 1470 int hardirq_context; 1471 unsigned long softirq_disable_ip; 1472 unsigned long softirq_enable_ip; 1473 unsigned int softirq_disable_event; 1474 unsigned int softirq_enable_event; 1475 int softirqs_enabled; 1476 int softirq_context; 1477#endif 1478#ifdef CONFIG_LOCKDEP 1479# define MAX_LOCK_DEPTH 48UL 1480 u64 curr_chain_key; 1481 int lockdep_depth; 1482 unsigned int lockdep_recursion; 1483 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1484 gfp_t lockdep_reclaim_gfp; 1485#endif 1486 1487/* journalling filesystem info */ 1488 void *journal_info; 1489 1490/* stacked block device info */ 1491 struct bio_list *bio_list; 1492 1493#ifdef CONFIG_BLOCK 1494/* stack plugging */ 1495 struct blk_plug *plug; 1496#endif 1497 1498/* VM state */ 1499 struct reclaim_state *reclaim_state; 1500 1501 struct backing_dev_info *backing_dev_info; 1502 1503 struct io_context *io_context; 1504 1505 unsigned long ptrace_message; 1506 siginfo_t *last_siginfo; /* For ptrace use. */ 1507 struct task_io_accounting ioac; 1508#if defined(CONFIG_TASK_XACCT) 1509 u64 acct_rss_mem1; /* accumulated rss usage */ 1510 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1511 cputime_t acct_timexpd; /* stime + utime since last update */ 1512#endif 1513#ifdef CONFIG_CPUSETS 1514 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1515 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1516 int cpuset_mem_spread_rotor; 1517 int cpuset_slab_spread_rotor; 1518#endif 1519#ifdef CONFIG_CGROUPS 1520 /* Control Group info protected by css_set_lock */ 1521 struct css_set __rcu *cgroups; 1522 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1523 struct list_head cg_list; 1524#endif 1525#ifdef CONFIG_FUTEX 1526 struct robust_list_head __user *robust_list; 1527#ifdef CONFIG_COMPAT 1528 struct compat_robust_list_head __user *compat_robust_list; 1529#endif 1530 struct list_head pi_state_list; 1531 struct futex_pi_state *pi_state_cache; 1532#endif 1533#ifdef CONFIG_PERF_EVENTS 1534 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1535 struct mutex perf_event_mutex; 1536 struct list_head perf_event_list; 1537#endif 1538#ifdef CONFIG_DEBUG_PREEMPT 1539 unsigned long preempt_disable_ip; 1540#endif 1541#ifdef CONFIG_NUMA 1542 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1543 short il_next; 1544 short pref_node_fork; 1545#endif 1546#ifdef CONFIG_NUMA_BALANCING 1547 int numa_scan_seq; 1548 unsigned int numa_scan_period; 1549 unsigned int numa_scan_period_max; 1550 int numa_preferred_nid; 1551 unsigned long numa_migrate_retry; 1552 u64 node_stamp; /* migration stamp */ 1553 u64 last_task_numa_placement; 1554 u64 last_sum_exec_runtime; 1555 struct callback_head numa_work; 1556 1557 struct list_head numa_entry; 1558 struct numa_group *numa_group; 1559 1560 /* 1561 * Exponential decaying average of faults on a per-node basis. 1562 * Scheduling placement decisions are made based on the these counts. 1563 * The values remain static for the duration of a PTE scan 1564 */ 1565 unsigned long *numa_faults_memory; 1566 unsigned long total_numa_faults; 1567 1568 /* 1569 * numa_faults_buffer records faults per node during the current 1570 * scan window. When the scan completes, the counts in 1571 * numa_faults_memory decay and these values are copied. 1572 */ 1573 unsigned long *numa_faults_buffer_memory; 1574 1575 /* 1576 * Track the nodes the process was running on when a NUMA hinting 1577 * fault was incurred. 1578 */ 1579 unsigned long *numa_faults_cpu; 1580 unsigned long *numa_faults_buffer_cpu; 1581 1582 /* 1583 * numa_faults_locality tracks if faults recorded during the last 1584 * scan window were remote/local. The task scan period is adapted 1585 * based on the locality of the faults with different weights 1586 * depending on whether they were shared or private faults 1587 */ 1588 unsigned long numa_faults_locality[2]; 1589 1590 unsigned long numa_pages_migrated; 1591#endif /* CONFIG_NUMA_BALANCING */ 1592 1593 struct rcu_head rcu; 1594 1595 /* 1596 * cache last used pipe for splice 1597 */ 1598 struct pipe_inode_info *splice_pipe; 1599 1600 struct page_frag task_frag; 1601 1602#ifdef CONFIG_TASK_DELAY_ACCT 1603 struct task_delay_info *delays; 1604#endif 1605#ifdef CONFIG_FAULT_INJECTION 1606 int make_it_fail; 1607#endif 1608 /* 1609 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1610 * balance_dirty_pages() for some dirty throttling pause 1611 */ 1612 int nr_dirtied; 1613 int nr_dirtied_pause; 1614 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1615 1616#ifdef CONFIG_LATENCYTOP 1617 int latency_record_count; 1618 struct latency_record latency_record[LT_SAVECOUNT]; 1619#endif 1620 /* 1621 * time slack values; these are used to round up poll() and 1622 * select() etc timeout values. These are in nanoseconds. 1623 */ 1624 unsigned long timer_slack_ns; 1625 unsigned long default_timer_slack_ns; 1626 1627#ifdef CONFIG_FUNCTION_GRAPH_TRACER 1628 /* Index of current stored address in ret_stack */ 1629 int curr_ret_stack; 1630 /* Stack of return addresses for return function tracing */ 1631 struct ftrace_ret_stack *ret_stack; 1632 /* time stamp for last schedule */ 1633 unsigned long long ftrace_timestamp; 1634 /* 1635 * Number of functions that haven't been traced 1636 * because of depth overrun. 1637 */ 1638 atomic_t trace_overrun; 1639 /* Pause for the tracing */ 1640 atomic_t tracing_graph_pause; 1641#endif 1642#ifdef CONFIG_TRACING 1643 /* state flags for use by tracers */ 1644 unsigned long trace; 1645 /* bitmask and counter of trace recursion */ 1646 unsigned long trace_recursion; 1647#endif /* CONFIG_TRACING */ 1648#ifdef CONFIG_MEMCG /* memcg uses this to do batch job */ 1649 unsigned int memcg_kmem_skip_account; 1650 struct memcg_oom_info { 1651 struct mem_cgroup *memcg; 1652 gfp_t gfp_mask; 1653 int order; 1654 unsigned int may_oom:1; 1655 } memcg_oom; 1656#endif 1657#ifdef CONFIG_UPROBES 1658 struct uprobe_task *utask; 1659#endif 1660#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1661 unsigned int sequential_io; 1662 unsigned int sequential_io_avg; 1663#endif 1664}; 1665 1666/* Future-safe accessor for struct task_struct's cpus_allowed. */ 1667#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1668 1669#define TNF_MIGRATED 0x01 1670#define TNF_NO_GROUP 0x02 1671#define TNF_SHARED 0x04 1672#define TNF_FAULT_LOCAL 0x08 1673 1674#ifdef CONFIG_NUMA_BALANCING 1675extern void task_numa_fault(int last_node, int node, int pages, int flags); 1676extern pid_t task_numa_group_id(struct task_struct *p); 1677extern void set_numabalancing_state(bool enabled); 1678extern void task_numa_free(struct task_struct *p); 1679extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page, 1680 int src_nid, int dst_cpu); 1681#else 1682static inline void task_numa_fault(int last_node, int node, int pages, 1683 int flags) 1684{ 1685} 1686static inline pid_t task_numa_group_id(struct task_struct *p) 1687{ 1688 return 0; 1689} 1690static inline void set_numabalancing_state(bool enabled) 1691{ 1692} 1693static inline void task_numa_free(struct task_struct *p) 1694{ 1695} 1696static inline bool should_numa_migrate_memory(struct task_struct *p, 1697 struct page *page, int src_nid, int dst_cpu) 1698{ 1699 return true; 1700} 1701#endif 1702 1703static inline struct pid *task_pid(struct task_struct *task) 1704{ 1705 return task->pids[PIDTYPE_PID].pid; 1706} 1707 1708static inline struct pid *task_tgid(struct task_struct *task) 1709{ 1710 return task->group_leader->pids[PIDTYPE_PID].pid; 1711} 1712 1713/* 1714 * Without tasklist or rcu lock it is not safe to dereference 1715 * the result of task_pgrp/task_session even if task == current, 1716 * we can race with another thread doing sys_setsid/sys_setpgid. 1717 */ 1718static inline struct pid *task_pgrp(struct task_struct *task) 1719{ 1720 return task->group_leader->pids[PIDTYPE_PGID].pid; 1721} 1722 1723static inline struct pid *task_session(struct task_struct *task) 1724{ 1725 return task->group_leader->pids[PIDTYPE_SID].pid; 1726} 1727 1728struct pid_namespace; 1729 1730/* 1731 * the helpers to get the task's different pids as they are seen 1732 * from various namespaces 1733 * 1734 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1735 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1736 * current. 1737 * task_xid_nr_ns() : id seen from the ns specified; 1738 * 1739 * set_task_vxid() : assigns a virtual id to a task; 1740 * 1741 * see also pid_nr() etc in include/linux/pid.h 1742 */ 1743pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1744 struct pid_namespace *ns); 1745 1746static inline pid_t task_pid_nr(struct task_struct *tsk) 1747{ 1748 return tsk->pid; 1749} 1750 1751static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1752 struct pid_namespace *ns) 1753{ 1754 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1755} 1756 1757static inline pid_t task_pid_vnr(struct task_struct *tsk) 1758{ 1759 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1760} 1761 1762 1763static inline pid_t task_tgid_nr(struct task_struct *tsk) 1764{ 1765 return tsk->tgid; 1766} 1767 1768pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1769 1770static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1771{ 1772 return pid_vnr(task_tgid(tsk)); 1773} 1774 1775 1776static inline int pid_alive(const struct task_struct *p); 1777static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 1778{ 1779 pid_t pid = 0; 1780 1781 rcu_read_lock(); 1782 if (pid_alive(tsk)) 1783 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 1784 rcu_read_unlock(); 1785 1786 return pid; 1787} 1788 1789static inline pid_t task_ppid_nr(const struct task_struct *tsk) 1790{ 1791 return task_ppid_nr_ns(tsk, &init_pid_ns); 1792} 1793 1794static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1795 struct pid_namespace *ns) 1796{ 1797 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1798} 1799 1800static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1801{ 1802 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1803} 1804 1805 1806static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1807 struct pid_namespace *ns) 1808{ 1809 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1810} 1811 1812static inline pid_t task_session_vnr(struct task_struct *tsk) 1813{ 1814 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1815} 1816 1817/* obsolete, do not use */ 1818static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1819{ 1820 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1821} 1822 1823/** 1824 * pid_alive - check that a task structure is not stale 1825 * @p: Task structure to be checked. 1826 * 1827 * Test if a process is not yet dead (at most zombie state) 1828 * If pid_alive fails, then pointers within the task structure 1829 * can be stale and must not be dereferenced. 1830 * 1831 * Return: 1 if the process is alive. 0 otherwise. 1832 */ 1833static inline int pid_alive(const struct task_struct *p) 1834{ 1835 return p->pids[PIDTYPE_PID].pid != NULL; 1836} 1837 1838/** 1839 * is_global_init - check if a task structure is init 1840 * @tsk: Task structure to be checked. 1841 * 1842 * Check if a task structure is the first user space task the kernel created. 1843 * 1844 * Return: 1 if the task structure is init. 0 otherwise. 1845 */ 1846static inline int is_global_init(struct task_struct *tsk) 1847{ 1848 return tsk->pid == 1; 1849} 1850 1851extern struct pid *cad_pid; 1852 1853extern void free_task(struct task_struct *tsk); 1854#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1855 1856extern void __put_task_struct(struct task_struct *t); 1857 1858static inline void put_task_struct(struct task_struct *t) 1859{ 1860 if (atomic_dec_and_test(&t->usage)) 1861 __put_task_struct(t); 1862} 1863 1864#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1865extern void task_cputime(struct task_struct *t, 1866 cputime_t *utime, cputime_t *stime); 1867extern void task_cputime_scaled(struct task_struct *t, 1868 cputime_t *utimescaled, cputime_t *stimescaled); 1869extern cputime_t task_gtime(struct task_struct *t); 1870#else 1871static inline void task_cputime(struct task_struct *t, 1872 cputime_t *utime, cputime_t *stime) 1873{ 1874 if (utime) 1875 *utime = t->utime; 1876 if (stime) 1877 *stime = t->stime; 1878} 1879 1880static inline void task_cputime_scaled(struct task_struct *t, 1881 cputime_t *utimescaled, 1882 cputime_t *stimescaled) 1883{ 1884 if (utimescaled) 1885 *utimescaled = t->utimescaled; 1886 if (stimescaled) 1887 *stimescaled = t->stimescaled; 1888} 1889 1890static inline cputime_t task_gtime(struct task_struct *t) 1891{ 1892 return t->gtime; 1893} 1894#endif 1895extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1896extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1897 1898/* 1899 * Per process flags 1900 */ 1901#define PF_EXITING 0x00000004 /* getting shut down */ 1902#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1903#define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 1904#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1905#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1906#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 1907#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1908#define PF_DUMPCORE 0x00000200 /* dumped core */ 1909#define PF_SIGNALED 0x00000400 /* killed by a signal */ 1910#define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1911#define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 1912#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1913#define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 1914#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1915#define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1916#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1917#define PF_KSWAPD 0x00040000 /* I am kswapd */ 1918#define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 1919#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1920#define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1921#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1922#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1923#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 1924#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1925#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1926#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1927#define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 1928 1929/* 1930 * Only the _current_ task can read/write to tsk->flags, but other 1931 * tasks can access tsk->flags in readonly mode for example 1932 * with tsk_used_math (like during threaded core dumping). 1933 * There is however an exception to this rule during ptrace 1934 * or during fork: the ptracer task is allowed to write to the 1935 * child->flags of its traced child (same goes for fork, the parent 1936 * can write to the child->flags), because we're guaranteed the 1937 * child is not running and in turn not changing child->flags 1938 * at the same time the parent does it. 1939 */ 1940#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1941#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1942#define clear_used_math() clear_stopped_child_used_math(current) 1943#define set_used_math() set_stopped_child_used_math(current) 1944#define conditional_stopped_child_used_math(condition, child) \ 1945 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1946#define conditional_used_math(condition) \ 1947 conditional_stopped_child_used_math(condition, current) 1948#define copy_to_stopped_child_used_math(child) \ 1949 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1950/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1951#define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1952#define used_math() tsk_used_math(current) 1953 1954/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags 1955 * __GFP_FS is also cleared as it implies __GFP_IO. 1956 */ 1957static inline gfp_t memalloc_noio_flags(gfp_t flags) 1958{ 1959 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 1960 flags &= ~(__GFP_IO | __GFP_FS); 1961 return flags; 1962} 1963 1964static inline unsigned int memalloc_noio_save(void) 1965{ 1966 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 1967 current->flags |= PF_MEMALLOC_NOIO; 1968 return flags; 1969} 1970 1971static inline void memalloc_noio_restore(unsigned int flags) 1972{ 1973 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 1974} 1975 1976/* Per-process atomic flags. */ 1977#define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1978#define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1979#define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1980 1981 1982#define TASK_PFA_TEST(name, func) \ 1983 static inline bool task_##func(struct task_struct *p) \ 1984 { return test_bit(PFA_##name, &p->atomic_flags); } 1985#define TASK_PFA_SET(name, func) \ 1986 static inline void task_set_##func(struct task_struct *p) \ 1987 { set_bit(PFA_##name, &p->atomic_flags); } 1988#define TASK_PFA_CLEAR(name, func) \ 1989 static inline void task_clear_##func(struct task_struct *p) \ 1990 { clear_bit(PFA_##name, &p->atomic_flags); } 1991 1992TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1993TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1994 1995TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1996TASK_PFA_SET(SPREAD_PAGE, spread_page) 1997TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1998 1999TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 2000TASK_PFA_SET(SPREAD_SLAB, spread_slab) 2001TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 2002 2003/* 2004 * task->jobctl flags 2005 */ 2006#define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 2007 2008#define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 2009#define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 2010#define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 2011#define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 2012#define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 2013#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 2014#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 2015 2016#define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) 2017#define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) 2018#define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) 2019#define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) 2020#define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) 2021#define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) 2022#define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) 2023 2024#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 2025#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 2026 2027extern bool task_set_jobctl_pending(struct task_struct *task, 2028 unsigned int mask); 2029extern void task_clear_jobctl_trapping(struct task_struct *task); 2030extern void task_clear_jobctl_pending(struct task_struct *task, 2031 unsigned int mask); 2032 2033static inline void rcu_copy_process(struct task_struct *p) 2034{ 2035#ifdef CONFIG_PREEMPT_RCU 2036 p->rcu_read_lock_nesting = 0; 2037 p->rcu_read_unlock_special.s = 0; 2038 p->rcu_blocked_node = NULL; 2039 INIT_LIST_HEAD(&p->rcu_node_entry); 2040#endif /* #ifdef CONFIG_PREEMPT_RCU */ 2041#ifdef CONFIG_TASKS_RCU 2042 p->rcu_tasks_holdout = false; 2043 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); 2044 p->rcu_tasks_idle_cpu = -1; 2045#endif /* #ifdef CONFIG_TASKS_RCU */ 2046} 2047 2048static inline void tsk_restore_flags(struct task_struct *task, 2049 unsigned long orig_flags, unsigned long flags) 2050{ 2051 task->flags &= ~flags; 2052 task->flags |= orig_flags & flags; 2053} 2054 2055#ifdef CONFIG_SMP 2056extern void do_set_cpus_allowed(struct task_struct *p, 2057 const struct cpumask *new_mask); 2058 2059extern int set_cpus_allowed_ptr(struct task_struct *p, 2060 const struct cpumask *new_mask); 2061#else 2062static inline void do_set_cpus_allowed(struct task_struct *p, 2063 const struct cpumask *new_mask) 2064{ 2065} 2066static inline int set_cpus_allowed_ptr(struct task_struct *p, 2067 const struct cpumask *new_mask) 2068{ 2069 if (!cpumask_test_cpu(0, new_mask)) 2070 return -EINVAL; 2071 return 0; 2072} 2073#endif 2074 2075#ifdef CONFIG_NO_HZ_COMMON 2076void calc_load_enter_idle(void); 2077void calc_load_exit_idle(void); 2078#else 2079static inline void calc_load_enter_idle(void) { } 2080static inline void calc_load_exit_idle(void) { } 2081#endif /* CONFIG_NO_HZ_COMMON */ 2082 2083#ifndef CONFIG_CPUMASK_OFFSTACK 2084static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 2085{ 2086 return set_cpus_allowed_ptr(p, &new_mask); 2087} 2088#endif 2089 2090/* 2091 * Do not use outside of architecture code which knows its limitations. 2092 * 2093 * sched_clock() has no promise of monotonicity or bounded drift between 2094 * CPUs, use (which you should not) requires disabling IRQs. 2095 * 2096 * Please use one of the three interfaces below. 2097 */ 2098extern unsigned long long notrace sched_clock(void); 2099/* 2100 * See the comment in kernel/sched/clock.c 2101 */ 2102extern u64 cpu_clock(int cpu); 2103extern u64 local_clock(void); 2104extern u64 sched_clock_cpu(int cpu); 2105 2106 2107extern void sched_clock_init(void); 2108 2109#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2110static inline void sched_clock_tick(void) 2111{ 2112} 2113 2114static inline void sched_clock_idle_sleep_event(void) 2115{ 2116} 2117 2118static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 2119{ 2120} 2121#else 2122/* 2123 * Architectures can set this to 1 if they have specified 2124 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 2125 * but then during bootup it turns out that sched_clock() 2126 * is reliable after all: 2127 */ 2128extern int sched_clock_stable(void); 2129extern void set_sched_clock_stable(void); 2130extern void clear_sched_clock_stable(void); 2131 2132extern void sched_clock_tick(void); 2133extern void sched_clock_idle_sleep_event(void); 2134extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2135#endif 2136 2137#ifdef CONFIG_IRQ_TIME_ACCOUNTING 2138/* 2139 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 2140 * The reason for this explicit opt-in is not to have perf penalty with 2141 * slow sched_clocks. 2142 */ 2143extern void enable_sched_clock_irqtime(void); 2144extern void disable_sched_clock_irqtime(void); 2145#else 2146static inline void enable_sched_clock_irqtime(void) {} 2147static inline void disable_sched_clock_irqtime(void) {} 2148#endif 2149 2150extern unsigned long long 2151task_sched_runtime(struct task_struct *task); 2152 2153/* sched_exec is called by processes performing an exec */ 2154#ifdef CONFIG_SMP 2155extern void sched_exec(void); 2156#else 2157#define sched_exec() {} 2158#endif 2159 2160extern void sched_clock_idle_sleep_event(void); 2161extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2162 2163#ifdef CONFIG_HOTPLUG_CPU 2164extern void idle_task_exit(void); 2165#else 2166static inline void idle_task_exit(void) {} 2167#endif 2168 2169#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 2170extern void wake_up_nohz_cpu(int cpu); 2171#else 2172static inline void wake_up_nohz_cpu(int cpu) { } 2173#endif 2174 2175#ifdef CONFIG_NO_HZ_FULL 2176extern bool sched_can_stop_tick(void); 2177extern u64 scheduler_tick_max_deferment(void); 2178#else 2179static inline bool sched_can_stop_tick(void) { return false; } 2180#endif 2181 2182#ifdef CONFIG_SCHED_AUTOGROUP 2183extern void sched_autogroup_create_attach(struct task_struct *p); 2184extern void sched_autogroup_detach(struct task_struct *p); 2185extern void sched_autogroup_fork(struct signal_struct *sig); 2186extern void sched_autogroup_exit(struct signal_struct *sig); 2187#ifdef CONFIG_PROC_FS 2188extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2189extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2190#endif 2191#else 2192static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2193static inline void sched_autogroup_detach(struct task_struct *p) { } 2194static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2195static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2196#endif 2197 2198extern int yield_to(struct task_struct *p, bool preempt); 2199extern void set_user_nice(struct task_struct *p, long nice); 2200extern int task_prio(const struct task_struct *p); 2201/** 2202 * task_nice - return the nice value of a given task. 2203 * @p: the task in question. 2204 * 2205 * Return: The nice value [ -20 ... 0 ... 19 ]. 2206 */ 2207static inline int task_nice(const struct task_struct *p) 2208{ 2209 return PRIO_TO_NICE((p)->static_prio); 2210} 2211extern int can_nice(const struct task_struct *p, const int nice); 2212extern int task_curr(const struct task_struct *p); 2213extern int idle_cpu(int cpu); 2214extern int sched_setscheduler(struct task_struct *, int, 2215 const struct sched_param *); 2216extern int sched_setscheduler_nocheck(struct task_struct *, int, 2217 const struct sched_param *); 2218extern int sched_setattr(struct task_struct *, 2219 const struct sched_attr *); 2220extern struct task_struct *idle_task(int cpu); 2221/** 2222 * is_idle_task - is the specified task an idle task? 2223 * @p: the task in question. 2224 * 2225 * Return: 1 if @p is an idle task. 0 otherwise. 2226 */ 2227static inline bool is_idle_task(const struct task_struct *p) 2228{ 2229 return p->pid == 0; 2230} 2231extern struct task_struct *curr_task(int cpu); 2232extern void set_curr_task(int cpu, struct task_struct *p); 2233 2234void yield(void); 2235 2236/* 2237 * The default (Linux) execution domain. 2238 */ 2239extern struct exec_domain default_exec_domain; 2240 2241union thread_union { 2242 struct thread_info thread_info; 2243 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2244}; 2245 2246#ifndef __HAVE_ARCH_KSTACK_END 2247static inline int kstack_end(void *addr) 2248{ 2249 /* Reliable end of stack detection: 2250 * Some APM bios versions misalign the stack 2251 */ 2252 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2253} 2254#endif 2255 2256extern union thread_union init_thread_union; 2257extern struct task_struct init_task; 2258 2259extern struct mm_struct init_mm; 2260 2261extern struct pid_namespace init_pid_ns; 2262 2263/* 2264 * find a task by one of its numerical ids 2265 * 2266 * find_task_by_pid_ns(): 2267 * finds a task by its pid in the specified namespace 2268 * find_task_by_vpid(): 2269 * finds a task by its virtual pid 2270 * 2271 * see also find_vpid() etc in include/linux/pid.h 2272 */ 2273 2274extern struct task_struct *find_task_by_vpid(pid_t nr); 2275extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2276 struct pid_namespace *ns); 2277 2278/* per-UID process charging. */ 2279extern struct user_struct * alloc_uid(kuid_t); 2280static inline struct user_struct *get_uid(struct user_struct *u) 2281{ 2282 atomic_inc(&u->__count); 2283 return u; 2284} 2285extern void free_uid(struct user_struct *); 2286 2287#include <asm/current.h> 2288 2289extern void xtime_update(unsigned long ticks); 2290 2291extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2292extern int wake_up_process(struct task_struct *tsk); 2293extern void wake_up_new_task(struct task_struct *tsk); 2294#ifdef CONFIG_SMP 2295 extern void kick_process(struct task_struct *tsk); 2296#else 2297 static inline void kick_process(struct task_struct *tsk) { } 2298#endif 2299extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 2300extern void sched_dead(struct task_struct *p); 2301 2302extern void proc_caches_init(void); 2303extern void flush_signals(struct task_struct *); 2304extern void __flush_signals(struct task_struct *); 2305extern void ignore_signals(struct task_struct *); 2306extern void flush_signal_handlers(struct task_struct *, int force_default); 2307extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2308 2309static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2310{ 2311 unsigned long flags; 2312 int ret; 2313 2314 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2315 ret = dequeue_signal(tsk, mask, info); 2316 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2317 2318 return ret; 2319} 2320 2321extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2322 sigset_t *mask); 2323extern void unblock_all_signals(void); 2324extern void release_task(struct task_struct * p); 2325extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2326extern int force_sigsegv(int, struct task_struct *); 2327extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2328extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2329extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2330extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2331 const struct cred *, u32); 2332extern int kill_pgrp(struct pid *pid, int sig, int priv); 2333extern int kill_pid(struct pid *pid, int sig, int priv); 2334extern int kill_proc_info(int, struct siginfo *, pid_t); 2335extern __must_check bool do_notify_parent(struct task_struct *, int); 2336extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2337extern void force_sig(int, struct task_struct *); 2338extern int send_sig(int, struct task_struct *, int); 2339extern int zap_other_threads(struct task_struct *p); 2340extern struct sigqueue *sigqueue_alloc(void); 2341extern void sigqueue_free(struct sigqueue *); 2342extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2343extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2344 2345static inline void restore_saved_sigmask(void) 2346{ 2347 if (test_and_clear_restore_sigmask()) 2348 __set_current_blocked(&current->saved_sigmask); 2349} 2350 2351static inline sigset_t *sigmask_to_save(void) 2352{ 2353 sigset_t *res = &current->blocked; 2354 if (unlikely(test_restore_sigmask())) 2355 res = &current->saved_sigmask; 2356 return res; 2357} 2358 2359static inline int kill_cad_pid(int sig, int priv) 2360{ 2361 return kill_pid(cad_pid, sig, priv); 2362} 2363 2364/* These can be the second arg to send_sig_info/send_group_sig_info. */ 2365#define SEND_SIG_NOINFO ((struct siginfo *) 0) 2366#define SEND_SIG_PRIV ((struct siginfo *) 1) 2367#define SEND_SIG_FORCED ((struct siginfo *) 2) 2368 2369/* 2370 * True if we are on the alternate signal stack. 2371 */ 2372static inline int on_sig_stack(unsigned long sp) 2373{ 2374#ifdef CONFIG_STACK_GROWSUP 2375 return sp >= current->sas_ss_sp && 2376 sp - current->sas_ss_sp < current->sas_ss_size; 2377#else 2378 return sp > current->sas_ss_sp && 2379 sp - current->sas_ss_sp <= current->sas_ss_size; 2380#endif 2381} 2382 2383static inline int sas_ss_flags(unsigned long sp) 2384{ 2385 if (!current->sas_ss_size) 2386 return SS_DISABLE; 2387 2388 return on_sig_stack(sp) ? SS_ONSTACK : 0; 2389} 2390 2391static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2392{ 2393 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2394#ifdef CONFIG_STACK_GROWSUP 2395 return current->sas_ss_sp; 2396#else 2397 return current->sas_ss_sp + current->sas_ss_size; 2398#endif 2399 return sp; 2400} 2401 2402/* 2403 * Routines for handling mm_structs 2404 */ 2405extern struct mm_struct * mm_alloc(void); 2406 2407/* mmdrop drops the mm and the page tables */ 2408extern void __mmdrop(struct mm_struct *); 2409static inline void mmdrop(struct mm_struct * mm) 2410{ 2411 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2412 __mmdrop(mm); 2413} 2414 2415/* mmput gets rid of the mappings and all user-space */ 2416extern void mmput(struct mm_struct *); 2417/* Grab a reference to a task's mm, if it is not already going away */ 2418extern struct mm_struct *get_task_mm(struct task_struct *task); 2419/* 2420 * Grab a reference to a task's mm, if it is not already going away 2421 * and ptrace_may_access with the mode parameter passed to it 2422 * succeeds. 2423 */ 2424extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2425/* Remove the current tasks stale references to the old mm_struct */ 2426extern void mm_release(struct task_struct *, struct mm_struct *); 2427 2428extern int copy_thread(unsigned long, unsigned long, unsigned long, 2429 struct task_struct *); 2430extern void flush_thread(void); 2431extern void exit_thread(void); 2432 2433extern void exit_files(struct task_struct *); 2434extern void __cleanup_sighand(struct sighand_struct *); 2435 2436extern void exit_itimers(struct signal_struct *); 2437extern void flush_itimer_signals(void); 2438 2439extern void do_group_exit(int); 2440 2441extern int do_execve(struct filename *, 2442 const char __user * const __user *, 2443 const char __user * const __user *); 2444extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2445struct task_struct *fork_idle(int); 2446extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2447 2448extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 2449static inline void set_task_comm(struct task_struct *tsk, const char *from) 2450{ 2451 __set_task_comm(tsk, from, false); 2452} 2453extern char *get_task_comm(char *to, struct task_struct *tsk); 2454 2455#ifdef CONFIG_SMP 2456void scheduler_ipi(void); 2457extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2458#else 2459static inline void scheduler_ipi(void) { } 2460static inline unsigned long wait_task_inactive(struct task_struct *p, 2461 long match_state) 2462{ 2463 return 1; 2464} 2465#endif 2466 2467#define next_task(p) \ 2468 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2469 2470#define for_each_process(p) \ 2471 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2472 2473extern bool current_is_single_threaded(void); 2474 2475/* 2476 * Careful: do_each_thread/while_each_thread is a double loop so 2477 * 'break' will not work as expected - use goto instead. 2478 */ 2479#define do_each_thread(g, t) \ 2480 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2481 2482#define while_each_thread(g, t) \ 2483 while ((t = next_thread(t)) != g) 2484 2485#define __for_each_thread(signal, t) \ 2486 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) 2487 2488#define for_each_thread(p, t) \ 2489 __for_each_thread((p)->signal, t) 2490 2491/* Careful: this is a double loop, 'break' won't work as expected. */ 2492#define for_each_process_thread(p, t) \ 2493 for_each_process(p) for_each_thread(p, t) 2494 2495static inline int get_nr_threads(struct task_struct *tsk) 2496{ 2497 return tsk->signal->nr_threads; 2498} 2499 2500static inline bool thread_group_leader(struct task_struct *p) 2501{ 2502 return p->exit_signal >= 0; 2503} 2504 2505/* Do to the insanities of de_thread it is possible for a process 2506 * to have the pid of the thread group leader without actually being 2507 * the thread group leader. For iteration through the pids in proc 2508 * all we care about is that we have a task with the appropriate 2509 * pid, we don't actually care if we have the right task. 2510 */ 2511static inline bool has_group_leader_pid(struct task_struct *p) 2512{ 2513 return task_pid(p) == p->signal->leader_pid; 2514} 2515 2516static inline 2517bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 2518{ 2519 return p1->signal == p2->signal; 2520} 2521 2522static inline struct task_struct *next_thread(const struct task_struct *p) 2523{ 2524 return list_entry_rcu(p->thread_group.next, 2525 struct task_struct, thread_group); 2526} 2527 2528static inline int thread_group_empty(struct task_struct *p) 2529{ 2530 return list_empty(&p->thread_group); 2531} 2532 2533#define delay_group_leader(p) \ 2534 (thread_group_leader(p) && !thread_group_empty(p)) 2535 2536/* 2537 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2538 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2539 * pins the final release of task.io_context. Also protects ->cpuset and 2540 * ->cgroup.subsys[]. And ->vfork_done. 2541 * 2542 * Nests both inside and outside of read_lock(&tasklist_lock). 2543 * It must not be nested with write_lock_irq(&tasklist_lock), 2544 * neither inside nor outside. 2545 */ 2546static inline void task_lock(struct task_struct *p) 2547{ 2548 spin_lock(&p->alloc_lock); 2549} 2550 2551static inline void task_unlock(struct task_struct *p) 2552{ 2553 spin_unlock(&p->alloc_lock); 2554} 2555 2556extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2557 unsigned long *flags); 2558 2559static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2560 unsigned long *flags) 2561{ 2562 struct sighand_struct *ret; 2563 2564 ret = __lock_task_sighand(tsk, flags); 2565 (void)__cond_lock(&tsk->sighand->siglock, ret); 2566 return ret; 2567} 2568 2569static inline void unlock_task_sighand(struct task_struct *tsk, 2570 unsigned long *flags) 2571{ 2572 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2573} 2574 2575#ifdef CONFIG_CGROUPS 2576static inline void threadgroup_change_begin(struct task_struct *tsk) 2577{ 2578 down_read(&tsk->signal->group_rwsem); 2579} 2580static inline void threadgroup_change_end(struct task_struct *tsk) 2581{ 2582 up_read(&tsk->signal->group_rwsem); 2583} 2584 2585/** 2586 * threadgroup_lock - lock threadgroup 2587 * @tsk: member task of the threadgroup to lock 2588 * 2589 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter 2590 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or 2591 * change ->group_leader/pid. This is useful for cases where the threadgroup 2592 * needs to stay stable across blockable operations. 2593 * 2594 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for 2595 * synchronization. While held, no new task will be added to threadgroup 2596 * and no existing live task will have its PF_EXITING set. 2597 * 2598 * de_thread() does threadgroup_change_{begin|end}() when a non-leader 2599 * sub-thread becomes a new leader. 2600 */ 2601static inline void threadgroup_lock(struct task_struct *tsk) 2602{ 2603 down_write(&tsk->signal->group_rwsem); 2604} 2605 2606/** 2607 * threadgroup_unlock - unlock threadgroup 2608 * @tsk: member task of the threadgroup to unlock 2609 * 2610 * Reverse threadgroup_lock(). 2611 */ 2612static inline void threadgroup_unlock(struct task_struct *tsk) 2613{ 2614 up_write(&tsk->signal->group_rwsem); 2615} 2616#else 2617static inline void threadgroup_change_begin(struct task_struct *tsk) {} 2618static inline void threadgroup_change_end(struct task_struct *tsk) {} 2619static inline void threadgroup_lock(struct task_struct *tsk) {} 2620static inline void threadgroup_unlock(struct task_struct *tsk) {} 2621#endif 2622 2623#ifndef __HAVE_THREAD_FUNCTIONS 2624 2625#define task_thread_info(task) ((struct thread_info *)(task)->stack) 2626#define task_stack_page(task) ((task)->stack) 2627 2628static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2629{ 2630 *task_thread_info(p) = *task_thread_info(org); 2631 task_thread_info(p)->task = p; 2632} 2633 2634/* 2635 * Return the address of the last usable long on the stack. 2636 * 2637 * When the stack grows down, this is just above the thread 2638 * info struct. Going any lower will corrupt the threadinfo. 2639 * 2640 * When the stack grows up, this is the highest address. 2641 * Beyond that position, we corrupt data on the next page. 2642 */ 2643static inline unsigned long *end_of_stack(struct task_struct *p) 2644{ 2645#ifdef CONFIG_STACK_GROWSUP 2646 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1; 2647#else 2648 return (unsigned long *)(task_thread_info(p) + 1); 2649#endif 2650} 2651 2652#endif 2653#define task_stack_end_corrupted(task) \ 2654 (*(end_of_stack(task)) != STACK_END_MAGIC) 2655 2656static inline int object_is_on_stack(void *obj) 2657{ 2658 void *stack = task_stack_page(current); 2659 2660 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2661} 2662 2663extern void thread_info_cache_init(void); 2664 2665#ifdef CONFIG_DEBUG_STACK_USAGE 2666static inline unsigned long stack_not_used(struct task_struct *p) 2667{ 2668 unsigned long *n = end_of_stack(p); 2669 2670 do { /* Skip over canary */ 2671 n++; 2672 } while (!*n); 2673 2674 return (unsigned long)n - (unsigned long)end_of_stack(p); 2675} 2676#endif 2677extern void set_task_stack_end_magic(struct task_struct *tsk); 2678 2679/* set thread flags in other task's structures 2680 * - see asm/thread_info.h for TIF_xxxx flags available 2681 */ 2682static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2683{ 2684 set_ti_thread_flag(task_thread_info(tsk), flag); 2685} 2686 2687static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2688{ 2689 clear_ti_thread_flag(task_thread_info(tsk), flag); 2690} 2691 2692static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2693{ 2694 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2695} 2696 2697static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2698{ 2699 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2700} 2701 2702static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2703{ 2704 return test_ti_thread_flag(task_thread_info(tsk), flag); 2705} 2706 2707static inline void set_tsk_need_resched(struct task_struct *tsk) 2708{ 2709 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2710} 2711 2712static inline void clear_tsk_need_resched(struct task_struct *tsk) 2713{ 2714 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2715} 2716 2717static inline int test_tsk_need_resched(struct task_struct *tsk) 2718{ 2719 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2720} 2721 2722static inline int restart_syscall(void) 2723{ 2724 set_tsk_thread_flag(current, TIF_SIGPENDING); 2725 return -ERESTARTNOINTR; 2726} 2727 2728static inline int signal_pending(struct task_struct *p) 2729{ 2730 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2731} 2732 2733static inline int __fatal_signal_pending(struct task_struct *p) 2734{ 2735 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2736} 2737 2738static inline int fatal_signal_pending(struct task_struct *p) 2739{ 2740 return signal_pending(p) && __fatal_signal_pending(p); 2741} 2742 2743static inline int signal_pending_state(long state, struct task_struct *p) 2744{ 2745 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2746 return 0; 2747 if (!signal_pending(p)) 2748 return 0; 2749 2750 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2751} 2752 2753/* 2754 * cond_resched() and cond_resched_lock(): latency reduction via 2755 * explicit rescheduling in places that are safe. The return 2756 * value indicates whether a reschedule was done in fact. 2757 * cond_resched_lock() will drop the spinlock before scheduling, 2758 * cond_resched_softirq() will enable bhs before scheduling. 2759 */ 2760extern int _cond_resched(void); 2761 2762#define cond_resched() ({ \ 2763 __might_sleep(__FILE__, __LINE__, 0); \ 2764 _cond_resched(); \ 2765}) 2766 2767extern int __cond_resched_lock(spinlock_t *lock); 2768 2769#ifdef CONFIG_PREEMPT_COUNT 2770#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2771#else 2772#define PREEMPT_LOCK_OFFSET 0 2773#endif 2774 2775#define cond_resched_lock(lock) ({ \ 2776 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2777 __cond_resched_lock(lock); \ 2778}) 2779 2780extern int __cond_resched_softirq(void); 2781 2782#define cond_resched_softirq() ({ \ 2783 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2784 __cond_resched_softirq(); \ 2785}) 2786 2787static inline void cond_resched_rcu(void) 2788{ 2789#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 2790 rcu_read_unlock(); 2791 cond_resched(); 2792 rcu_read_lock(); 2793#endif 2794} 2795 2796/* 2797 * Does a critical section need to be broken due to another 2798 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2799 * but a general need for low latency) 2800 */ 2801static inline int spin_needbreak(spinlock_t *lock) 2802{ 2803#ifdef CONFIG_PREEMPT 2804 return spin_is_contended(lock); 2805#else 2806 return 0; 2807#endif 2808} 2809 2810/* 2811 * Idle thread specific functions to determine the need_resched 2812 * polling state. 2813 */ 2814#ifdef TIF_POLLING_NRFLAG 2815static inline int tsk_is_polling(struct task_struct *p) 2816{ 2817 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 2818} 2819 2820static inline void __current_set_polling(void) 2821{ 2822 set_thread_flag(TIF_POLLING_NRFLAG); 2823} 2824 2825static inline bool __must_check current_set_polling_and_test(void) 2826{ 2827 __current_set_polling(); 2828 2829 /* 2830 * Polling state must be visible before we test NEED_RESCHED, 2831 * paired by resched_curr() 2832 */ 2833 smp_mb__after_atomic(); 2834 2835 return unlikely(tif_need_resched()); 2836} 2837 2838static inline void __current_clr_polling(void) 2839{ 2840 clear_thread_flag(TIF_POLLING_NRFLAG); 2841} 2842 2843static inline bool __must_check current_clr_polling_and_test(void) 2844{ 2845 __current_clr_polling(); 2846 2847 /* 2848 * Polling state must be visible before we test NEED_RESCHED, 2849 * paired by resched_curr() 2850 */ 2851 smp_mb__after_atomic(); 2852 2853 return unlikely(tif_need_resched()); 2854} 2855 2856#else 2857static inline int tsk_is_polling(struct task_struct *p) { return 0; } 2858static inline void __current_set_polling(void) { } 2859static inline void __current_clr_polling(void) { } 2860 2861static inline bool __must_check current_set_polling_and_test(void) 2862{ 2863 return unlikely(tif_need_resched()); 2864} 2865static inline bool __must_check current_clr_polling_and_test(void) 2866{ 2867 return unlikely(tif_need_resched()); 2868} 2869#endif 2870 2871static inline void current_clr_polling(void) 2872{ 2873 __current_clr_polling(); 2874 2875 /* 2876 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit. 2877 * Once the bit is cleared, we'll get IPIs with every new 2878 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also 2879 * fold. 2880 */ 2881 smp_mb(); /* paired with resched_curr() */ 2882 2883 preempt_fold_need_resched(); 2884} 2885 2886static __always_inline bool need_resched(void) 2887{ 2888 return unlikely(tif_need_resched()); 2889} 2890 2891/* 2892 * Thread group CPU time accounting. 2893 */ 2894void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 2895void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 2896 2897static inline void thread_group_cputime_init(struct signal_struct *sig) 2898{ 2899 raw_spin_lock_init(&sig->cputimer.lock); 2900} 2901 2902/* 2903 * Reevaluate whether the task has signals pending delivery. 2904 * Wake the task if so. 2905 * This is required every time the blocked sigset_t changes. 2906 * callers must hold sighand->siglock. 2907 */ 2908extern void recalc_sigpending_and_wake(struct task_struct *t); 2909extern void recalc_sigpending(void); 2910 2911extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 2912 2913static inline void signal_wake_up(struct task_struct *t, bool resume) 2914{ 2915 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 2916} 2917static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 2918{ 2919 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 2920} 2921 2922/* 2923 * Wrappers for p->thread_info->cpu access. No-op on UP. 2924 */ 2925#ifdef CONFIG_SMP 2926 2927static inline unsigned int task_cpu(const struct task_struct *p) 2928{ 2929 return task_thread_info(p)->cpu; 2930} 2931 2932static inline int task_node(const struct task_struct *p) 2933{ 2934 return cpu_to_node(task_cpu(p)); 2935} 2936 2937extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2938 2939#else 2940 2941static inline unsigned int task_cpu(const struct task_struct *p) 2942{ 2943 return 0; 2944} 2945 2946static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2947{ 2948} 2949 2950#endif /* CONFIG_SMP */ 2951 2952extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2953extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2954 2955#ifdef CONFIG_CGROUP_SCHED 2956extern struct task_group root_task_group; 2957#endif /* CONFIG_CGROUP_SCHED */ 2958 2959extern int task_can_switch_user(struct user_struct *up, 2960 struct task_struct *tsk); 2961 2962#ifdef CONFIG_TASK_XACCT 2963static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2964{ 2965 tsk->ioac.rchar += amt; 2966} 2967 2968static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2969{ 2970 tsk->ioac.wchar += amt; 2971} 2972 2973static inline void inc_syscr(struct task_struct *tsk) 2974{ 2975 tsk->ioac.syscr++; 2976} 2977 2978static inline void inc_syscw(struct task_struct *tsk) 2979{ 2980 tsk->ioac.syscw++; 2981} 2982#else 2983static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2984{ 2985} 2986 2987static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2988{ 2989} 2990 2991static inline void inc_syscr(struct task_struct *tsk) 2992{ 2993} 2994 2995static inline void inc_syscw(struct task_struct *tsk) 2996{ 2997} 2998#endif 2999 3000#ifndef TASK_SIZE_OF 3001#define TASK_SIZE_OF(tsk) TASK_SIZE 3002#endif 3003 3004#ifdef CONFIG_MEMCG 3005extern void mm_update_next_owner(struct mm_struct *mm); 3006#else 3007static inline void mm_update_next_owner(struct mm_struct *mm) 3008{ 3009} 3010#endif /* CONFIG_MEMCG */ 3011 3012static inline unsigned long task_rlimit(const struct task_struct *tsk, 3013 unsigned int limit) 3014{ 3015 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); 3016} 3017 3018static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 3019 unsigned int limit) 3020{ 3021 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); 3022} 3023 3024static inline unsigned long rlimit(unsigned int limit) 3025{ 3026 return task_rlimit(current, limit); 3027} 3028 3029static inline unsigned long rlimit_max(unsigned int limit) 3030{ 3031 return task_rlimit_max(current, limit); 3032} 3033 3034#endif