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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/signal.h> 37#include <linux/compiler.h> 38#include <linux/completion.h> 39#include <linux/pid.h> 40#include <linux/percpu.h> 41#include <linux/topology.h> 42#include <linux/proportions.h> 43#include <linux/seccomp.h> 44#include <linux/rcupdate.h> 45#include <linux/rculist.h> 46#include <linux/rtmutex.h> 47 48#include <linux/time.h> 49#include <linux/param.h> 50#include <linux/resource.h> 51#include <linux/timer.h> 52#include <linux/hrtimer.h> 53#include <linux/task_io_accounting.h> 54#include <linux/latencytop.h> 55#include <linux/cred.h> 56#include <linux/llist.h> 57#include <linux/uidgid.h> 58#include <linux/gfp.h> 59 60#include <asm/processor.h> 61 62#define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */ 63 64/* 65 * Extended scheduling parameters data structure. 66 * 67 * This is needed because the original struct sched_param can not be 68 * altered without introducing ABI issues with legacy applications 69 * (e.g., in sched_getparam()). 70 * 71 * However, the possibility of specifying more than just a priority for 72 * the tasks may be useful for a wide variety of application fields, e.g., 73 * multimedia, streaming, automation and control, and many others. 74 * 75 * This variant (sched_attr) is meant at describing a so-called 76 * sporadic time-constrained task. In such model a task is specified by: 77 * - the activation period or minimum instance inter-arrival time; 78 * - the maximum (or average, depending on the actual scheduling 79 * discipline) computation time of all instances, a.k.a. runtime; 80 * - the deadline (relative to the actual activation time) of each 81 * instance. 82 * Very briefly, a periodic (sporadic) task asks for the execution of 83 * some specific computation --which is typically called an instance-- 84 * (at most) every period. Moreover, each instance typically lasts no more 85 * than the runtime and must be completed by time instant t equal to 86 * the instance activation time + the deadline. 87 * 88 * This is reflected by the actual fields of the sched_attr structure: 89 * 90 * @size size of the structure, for fwd/bwd compat. 91 * 92 * @sched_policy task's scheduling policy 93 * @sched_flags for customizing the scheduler behaviour 94 * @sched_nice task's nice value (SCHED_NORMAL/BATCH) 95 * @sched_priority task's static priority (SCHED_FIFO/RR) 96 * @sched_deadline representative of the task's deadline 97 * @sched_runtime representative of the task's runtime 98 * @sched_period representative of the task's period 99 * 100 * Given this task model, there are a multiplicity of scheduling algorithms 101 * and policies, that can be used to ensure all the tasks will make their 102 * timing constraints. 103 * 104 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the 105 * only user of this new interface. More information about the algorithm 106 * available in the scheduling class file or in Documentation/. 107 */ 108struct sched_attr { 109 u32 size; 110 111 u32 sched_policy; 112 u64 sched_flags; 113 114 /* SCHED_NORMAL, SCHED_BATCH */ 115 s32 sched_nice; 116 117 /* SCHED_FIFO, SCHED_RR */ 118 u32 sched_priority; 119 120 /* SCHED_DEADLINE */ 121 u64 sched_runtime; 122 u64 sched_deadline; 123 u64 sched_period; 124}; 125 126struct exec_domain; 127struct futex_pi_state; 128struct robust_list_head; 129struct bio_list; 130struct fs_struct; 131struct perf_event_context; 132struct blk_plug; 133struct filename; 134 135#define VMACACHE_BITS 2 136#define VMACACHE_SIZE (1U << VMACACHE_BITS) 137#define VMACACHE_MASK (VMACACHE_SIZE - 1) 138 139/* 140 * These are the constant used to fake the fixed-point load-average 141 * counting. Some notes: 142 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 143 * a load-average precision of 10 bits integer + 11 bits fractional 144 * - if you want to count load-averages more often, you need more 145 * precision, or rounding will get you. With 2-second counting freq, 146 * the EXP_n values would be 1981, 2034 and 2043 if still using only 147 * 11 bit fractions. 148 */ 149extern unsigned long avenrun[]; /* Load averages */ 150extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 151 152#define FSHIFT 11 /* nr of bits of precision */ 153#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 154#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 155#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 156#define EXP_5 2014 /* 1/exp(5sec/5min) */ 157#define EXP_15 2037 /* 1/exp(5sec/15min) */ 158 159#define CALC_LOAD(load,exp,n) \ 160 load *= exp; \ 161 load += n*(FIXED_1-exp); \ 162 load >>= FSHIFT; 163 164extern unsigned long total_forks; 165extern int nr_threads; 166DECLARE_PER_CPU(unsigned long, process_counts); 167extern int nr_processes(void); 168extern unsigned long nr_running(void); 169extern unsigned long nr_iowait(void); 170extern unsigned long nr_iowait_cpu(int cpu); 171extern unsigned long this_cpu_load(void); 172 173 174extern void calc_global_load(unsigned long ticks); 175extern void update_cpu_load_nohz(void); 176 177extern unsigned long get_parent_ip(unsigned long addr); 178 179extern void dump_cpu_task(int cpu); 180 181struct seq_file; 182struct cfs_rq; 183struct task_group; 184#ifdef CONFIG_SCHED_DEBUG 185extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 186extern void proc_sched_set_task(struct task_struct *p); 187extern void 188print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 189#endif 190 191/* 192 * Task state bitmask. NOTE! These bits are also 193 * encoded in fs/proc/array.c: get_task_state(). 194 * 195 * We have two separate sets of flags: task->state 196 * is about runnability, while task->exit_state are 197 * about the task exiting. Confusing, but this way 198 * modifying one set can't modify the other one by 199 * mistake. 200 */ 201#define TASK_RUNNING 0 202#define TASK_INTERRUPTIBLE 1 203#define TASK_UNINTERRUPTIBLE 2 204#define __TASK_STOPPED 4 205#define __TASK_TRACED 8 206/* in tsk->exit_state */ 207#define EXIT_DEAD 16 208#define EXIT_ZOMBIE 32 209#define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 210/* in tsk->state again */ 211#define TASK_DEAD 64 212#define TASK_WAKEKILL 128 213#define TASK_WAKING 256 214#define TASK_PARKED 512 215#define TASK_STATE_MAX 1024 216 217#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWP" 218 219extern char ___assert_task_state[1 - 2*!!( 220 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 221 222/* Convenience macros for the sake of set_task_state */ 223#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 224#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 225#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 226 227/* Convenience macros for the sake of wake_up */ 228#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 229#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 230 231/* get_task_state() */ 232#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 233 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 234 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD) 235 236#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 237#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 238#define task_is_stopped_or_traced(task) \ 239 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 240#define task_contributes_to_load(task) \ 241 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 242 (task->flags & PF_FROZEN) == 0) 243 244#define __set_task_state(tsk, state_value) \ 245 do { (tsk)->state = (state_value); } while (0) 246#define set_task_state(tsk, state_value) \ 247 set_mb((tsk)->state, (state_value)) 248 249/* 250 * set_current_state() includes a barrier so that the write of current->state 251 * is correctly serialised wrt the caller's subsequent test of whether to 252 * actually sleep: 253 * 254 * set_current_state(TASK_UNINTERRUPTIBLE); 255 * if (do_i_need_to_sleep()) 256 * schedule(); 257 * 258 * If the caller does not need such serialisation then use __set_current_state() 259 */ 260#define __set_current_state(state_value) \ 261 do { current->state = (state_value); } while (0) 262#define set_current_state(state_value) \ 263 set_mb(current->state, (state_value)) 264 265/* Task command name length */ 266#define TASK_COMM_LEN 16 267 268#include <linux/spinlock.h> 269 270/* 271 * This serializes "schedule()" and also protects 272 * the run-queue from deletions/modifications (but 273 * _adding_ to the beginning of the run-queue has 274 * a separate lock). 275 */ 276extern rwlock_t tasklist_lock; 277extern spinlock_t mmlist_lock; 278 279struct task_struct; 280 281#ifdef CONFIG_PROVE_RCU 282extern int lockdep_tasklist_lock_is_held(void); 283#endif /* #ifdef CONFIG_PROVE_RCU */ 284 285extern void sched_init(void); 286extern void sched_init_smp(void); 287extern asmlinkage void schedule_tail(struct task_struct *prev); 288extern void init_idle(struct task_struct *idle, int cpu); 289extern void init_idle_bootup_task(struct task_struct *idle); 290 291extern int runqueue_is_locked(int cpu); 292 293#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 294extern void nohz_balance_enter_idle(int cpu); 295extern void set_cpu_sd_state_idle(void); 296extern int get_nohz_timer_target(int pinned); 297#else 298static inline void nohz_balance_enter_idle(int cpu) { } 299static inline void set_cpu_sd_state_idle(void) { } 300static inline int get_nohz_timer_target(int pinned) 301{ 302 return smp_processor_id(); 303} 304#endif 305 306/* 307 * Only dump TASK_* tasks. (0 for all tasks) 308 */ 309extern void show_state_filter(unsigned long state_filter); 310 311static inline void show_state(void) 312{ 313 show_state_filter(0); 314} 315 316extern void show_regs(struct pt_regs *); 317 318/* 319 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 320 * task), SP is the stack pointer of the first frame that should be shown in the back 321 * trace (or NULL if the entire call-chain of the task should be shown). 322 */ 323extern void show_stack(struct task_struct *task, unsigned long *sp); 324 325void io_schedule(void); 326long io_schedule_timeout(long timeout); 327 328extern void cpu_init (void); 329extern void trap_init(void); 330extern void update_process_times(int user); 331extern void scheduler_tick(void); 332 333extern void sched_show_task(struct task_struct *p); 334 335#ifdef CONFIG_LOCKUP_DETECTOR 336extern void touch_softlockup_watchdog(void); 337extern void touch_softlockup_watchdog_sync(void); 338extern void touch_all_softlockup_watchdogs(void); 339extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 340 void __user *buffer, 341 size_t *lenp, loff_t *ppos); 342extern unsigned int softlockup_panic; 343void lockup_detector_init(void); 344#else 345static inline void touch_softlockup_watchdog(void) 346{ 347} 348static inline void touch_softlockup_watchdog_sync(void) 349{ 350} 351static inline void touch_all_softlockup_watchdogs(void) 352{ 353} 354static inline void lockup_detector_init(void) 355{ 356} 357#endif 358 359#ifdef CONFIG_DETECT_HUNG_TASK 360void reset_hung_task_detector(void); 361#else 362static inline void reset_hung_task_detector(void) 363{ 364} 365#endif 366 367/* Attach to any functions which should be ignored in wchan output. */ 368#define __sched __attribute__((__section__(".sched.text"))) 369 370/* Linker adds these: start and end of __sched functions */ 371extern char __sched_text_start[], __sched_text_end[]; 372 373/* Is this address in the __sched functions? */ 374extern int in_sched_functions(unsigned long addr); 375 376#define MAX_SCHEDULE_TIMEOUT LONG_MAX 377extern signed long schedule_timeout(signed long timeout); 378extern signed long schedule_timeout_interruptible(signed long timeout); 379extern signed long schedule_timeout_killable(signed long timeout); 380extern signed long schedule_timeout_uninterruptible(signed long timeout); 381asmlinkage void schedule(void); 382extern void schedule_preempt_disabled(void); 383 384struct nsproxy; 385struct user_namespace; 386 387#ifdef CONFIG_MMU 388extern void arch_pick_mmap_layout(struct mm_struct *mm); 389extern unsigned long 390arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 391 unsigned long, unsigned long); 392extern unsigned long 393arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 394 unsigned long len, unsigned long pgoff, 395 unsigned long flags); 396#else 397static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 398#endif 399 400#define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 401#define SUID_DUMP_USER 1 /* Dump as user of process */ 402#define SUID_DUMP_ROOT 2 /* Dump as root */ 403 404/* mm flags */ 405 406/* for SUID_DUMP_* above */ 407#define MMF_DUMPABLE_BITS 2 408#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 409 410extern void set_dumpable(struct mm_struct *mm, int value); 411/* 412 * This returns the actual value of the suid_dumpable flag. For things 413 * that are using this for checking for privilege transitions, it must 414 * test against SUID_DUMP_USER rather than treating it as a boolean 415 * value. 416 */ 417static inline int __get_dumpable(unsigned long mm_flags) 418{ 419 return mm_flags & MMF_DUMPABLE_MASK; 420} 421 422static inline int get_dumpable(struct mm_struct *mm) 423{ 424 return __get_dumpable(mm->flags); 425} 426 427/* coredump filter bits */ 428#define MMF_DUMP_ANON_PRIVATE 2 429#define MMF_DUMP_ANON_SHARED 3 430#define MMF_DUMP_MAPPED_PRIVATE 4 431#define MMF_DUMP_MAPPED_SHARED 5 432#define MMF_DUMP_ELF_HEADERS 6 433#define MMF_DUMP_HUGETLB_PRIVATE 7 434#define MMF_DUMP_HUGETLB_SHARED 8 435 436#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 437#define MMF_DUMP_FILTER_BITS 7 438#define MMF_DUMP_FILTER_MASK \ 439 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 440#define MMF_DUMP_FILTER_DEFAULT \ 441 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 442 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 443 444#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 445# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 446#else 447# define MMF_DUMP_MASK_DEFAULT_ELF 0 448#endif 449 /* leave room for more dump flags */ 450#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 451#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 452#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 453 454#define MMF_HAS_UPROBES 19 /* has uprobes */ 455#define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 456 457#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 458 459struct sighand_struct { 460 atomic_t count; 461 struct k_sigaction action[_NSIG]; 462 spinlock_t siglock; 463 wait_queue_head_t signalfd_wqh; 464}; 465 466struct pacct_struct { 467 int ac_flag; 468 long ac_exitcode; 469 unsigned long ac_mem; 470 cputime_t ac_utime, ac_stime; 471 unsigned long ac_minflt, ac_majflt; 472}; 473 474struct cpu_itimer { 475 cputime_t expires; 476 cputime_t incr; 477 u32 error; 478 u32 incr_error; 479}; 480 481/** 482 * struct cputime - snaphsot of system and user cputime 483 * @utime: time spent in user mode 484 * @stime: time spent in system mode 485 * 486 * Gathers a generic snapshot of user and system time. 487 */ 488struct cputime { 489 cputime_t utime; 490 cputime_t stime; 491}; 492 493/** 494 * struct task_cputime - collected CPU time counts 495 * @utime: time spent in user mode, in &cputime_t units 496 * @stime: time spent in kernel mode, in &cputime_t units 497 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 498 * 499 * This is an extension of struct cputime that includes the total runtime 500 * spent by the task from the scheduler point of view. 501 * 502 * As a result, this structure groups together three kinds of CPU time 503 * that are tracked for threads and thread groups. Most things considering 504 * CPU time want to group these counts together and treat all three 505 * of them in parallel. 506 */ 507struct task_cputime { 508 cputime_t utime; 509 cputime_t stime; 510 unsigned long long sum_exec_runtime; 511}; 512/* Alternate field names when used to cache expirations. */ 513#define prof_exp stime 514#define virt_exp utime 515#define sched_exp sum_exec_runtime 516 517#define INIT_CPUTIME \ 518 (struct task_cputime) { \ 519 .utime = 0, \ 520 .stime = 0, \ 521 .sum_exec_runtime = 0, \ 522 } 523 524#ifdef CONFIG_PREEMPT_COUNT 525#define PREEMPT_DISABLED (1 + PREEMPT_ENABLED) 526#else 527#define PREEMPT_DISABLED PREEMPT_ENABLED 528#endif 529 530/* 531 * Disable preemption until the scheduler is running. 532 * Reset by start_kernel()->sched_init()->init_idle(). 533 * 534 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 535 * before the scheduler is active -- see should_resched(). 536 */ 537#define INIT_PREEMPT_COUNT (PREEMPT_DISABLED + PREEMPT_ACTIVE) 538 539/** 540 * struct thread_group_cputimer - thread group interval timer counts 541 * @cputime: thread group interval timers. 542 * @running: non-zero when there are timers running and 543 * @cputime receives updates. 544 * @lock: lock for fields in this struct. 545 * 546 * This structure contains the version of task_cputime, above, that is 547 * used for thread group CPU timer calculations. 548 */ 549struct thread_group_cputimer { 550 struct task_cputime cputime; 551 int running; 552 raw_spinlock_t lock; 553}; 554 555#include <linux/rwsem.h> 556struct autogroup; 557 558/* 559 * NOTE! "signal_struct" does not have its own 560 * locking, because a shared signal_struct always 561 * implies a shared sighand_struct, so locking 562 * sighand_struct is always a proper superset of 563 * the locking of signal_struct. 564 */ 565struct signal_struct { 566 atomic_t sigcnt; 567 atomic_t live; 568 int nr_threads; 569 struct list_head thread_head; 570 571 wait_queue_head_t wait_chldexit; /* for wait4() */ 572 573 /* current thread group signal load-balancing target: */ 574 struct task_struct *curr_target; 575 576 /* shared signal handling: */ 577 struct sigpending shared_pending; 578 579 /* thread group exit support */ 580 int group_exit_code; 581 /* overloaded: 582 * - notify group_exit_task when ->count is equal to notify_count 583 * - everyone except group_exit_task is stopped during signal delivery 584 * of fatal signals, group_exit_task processes the signal. 585 */ 586 int notify_count; 587 struct task_struct *group_exit_task; 588 589 /* thread group stop support, overloads group_exit_code too */ 590 int group_stop_count; 591 unsigned int flags; /* see SIGNAL_* flags below */ 592 593 /* 594 * PR_SET_CHILD_SUBREAPER marks a process, like a service 595 * manager, to re-parent orphan (double-forking) child processes 596 * to this process instead of 'init'. The service manager is 597 * able to receive SIGCHLD signals and is able to investigate 598 * the process until it calls wait(). All children of this 599 * process will inherit a flag if they should look for a 600 * child_subreaper process at exit. 601 */ 602 unsigned int is_child_subreaper:1; 603 unsigned int has_child_subreaper:1; 604 605 /* POSIX.1b Interval Timers */ 606 int posix_timer_id; 607 struct list_head posix_timers; 608 609 /* ITIMER_REAL timer for the process */ 610 struct hrtimer real_timer; 611 struct pid *leader_pid; 612 ktime_t it_real_incr; 613 614 /* 615 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 616 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 617 * values are defined to 0 and 1 respectively 618 */ 619 struct cpu_itimer it[2]; 620 621 /* 622 * Thread group totals for process CPU timers. 623 * See thread_group_cputimer(), et al, for details. 624 */ 625 struct thread_group_cputimer cputimer; 626 627 /* Earliest-expiration cache. */ 628 struct task_cputime cputime_expires; 629 630 struct list_head cpu_timers[3]; 631 632 struct pid *tty_old_pgrp; 633 634 /* boolean value for session group leader */ 635 int leader; 636 637 struct tty_struct *tty; /* NULL if no tty */ 638 639#ifdef CONFIG_SCHED_AUTOGROUP 640 struct autogroup *autogroup; 641#endif 642 /* 643 * Cumulative resource counters for dead threads in the group, 644 * and for reaped dead child processes forked by this group. 645 * Live threads maintain their own counters and add to these 646 * in __exit_signal, except for the group leader. 647 */ 648 cputime_t utime, stime, cutime, cstime; 649 cputime_t gtime; 650 cputime_t cgtime; 651#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 652 struct cputime prev_cputime; 653#endif 654 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 655 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 656 unsigned long inblock, oublock, cinblock, coublock; 657 unsigned long maxrss, cmaxrss; 658 struct task_io_accounting ioac; 659 660 /* 661 * Cumulative ns of schedule CPU time fo dead threads in the 662 * group, not including a zombie group leader, (This only differs 663 * from jiffies_to_ns(utime + stime) if sched_clock uses something 664 * other than jiffies.) 665 */ 666 unsigned long long sum_sched_runtime; 667 668 /* 669 * We don't bother to synchronize most readers of this at all, 670 * because there is no reader checking a limit that actually needs 671 * to get both rlim_cur and rlim_max atomically, and either one 672 * alone is a single word that can safely be read normally. 673 * getrlimit/setrlimit use task_lock(current->group_leader) to 674 * protect this instead of the siglock, because they really 675 * have no need to disable irqs. 676 */ 677 struct rlimit rlim[RLIM_NLIMITS]; 678 679#ifdef CONFIG_BSD_PROCESS_ACCT 680 struct pacct_struct pacct; /* per-process accounting information */ 681#endif 682#ifdef CONFIG_TASKSTATS 683 struct taskstats *stats; 684#endif 685#ifdef CONFIG_AUDIT 686 unsigned audit_tty; 687 unsigned audit_tty_log_passwd; 688 struct tty_audit_buf *tty_audit_buf; 689#endif 690#ifdef CONFIG_CGROUPS 691 /* 692 * group_rwsem prevents new tasks from entering the threadgroup and 693 * member tasks from exiting,a more specifically, setting of 694 * PF_EXITING. fork and exit paths are protected with this rwsem 695 * using threadgroup_change_begin/end(). Users which require 696 * threadgroup to remain stable should use threadgroup_[un]lock() 697 * which also takes care of exec path. Currently, cgroup is the 698 * only user. 699 */ 700 struct rw_semaphore group_rwsem; 701#endif 702 703 oom_flags_t oom_flags; 704 short oom_score_adj; /* OOM kill score adjustment */ 705 short oom_score_adj_min; /* OOM kill score adjustment min value. 706 * Only settable by CAP_SYS_RESOURCE. */ 707 708 struct mutex cred_guard_mutex; /* guard against foreign influences on 709 * credential calculations 710 * (notably. ptrace) */ 711}; 712 713/* 714 * Bits in flags field of signal_struct. 715 */ 716#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 717#define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 718#define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 719#define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 720/* 721 * Pending notifications to parent. 722 */ 723#define SIGNAL_CLD_STOPPED 0x00000010 724#define SIGNAL_CLD_CONTINUED 0x00000020 725#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 726 727#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 728 729/* If true, all threads except ->group_exit_task have pending SIGKILL */ 730static inline int signal_group_exit(const struct signal_struct *sig) 731{ 732 return (sig->flags & SIGNAL_GROUP_EXIT) || 733 (sig->group_exit_task != NULL); 734} 735 736/* 737 * Some day this will be a full-fledged user tracking system.. 738 */ 739struct user_struct { 740 atomic_t __count; /* reference count */ 741 atomic_t processes; /* How many processes does this user have? */ 742 atomic_t sigpending; /* How many pending signals does this user have? */ 743#ifdef CONFIG_INOTIFY_USER 744 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 745 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 746#endif 747#ifdef CONFIG_FANOTIFY 748 atomic_t fanotify_listeners; 749#endif 750#ifdef CONFIG_EPOLL 751 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 752#endif 753#ifdef CONFIG_POSIX_MQUEUE 754 /* protected by mq_lock */ 755 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 756#endif 757 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 758 759#ifdef CONFIG_KEYS 760 struct key *uid_keyring; /* UID specific keyring */ 761 struct key *session_keyring; /* UID's default session keyring */ 762#endif 763 764 /* Hash table maintenance information */ 765 struct hlist_node uidhash_node; 766 kuid_t uid; 767 768#ifdef CONFIG_PERF_EVENTS 769 atomic_long_t locked_vm; 770#endif 771}; 772 773extern int uids_sysfs_init(void); 774 775extern struct user_struct *find_user(kuid_t); 776 777extern struct user_struct root_user; 778#define INIT_USER (&root_user) 779 780 781struct backing_dev_info; 782struct reclaim_state; 783 784#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 785struct sched_info { 786 /* cumulative counters */ 787 unsigned long pcount; /* # of times run on this cpu */ 788 unsigned long long run_delay; /* time spent waiting on a runqueue */ 789 790 /* timestamps */ 791 unsigned long long last_arrival,/* when we last ran on a cpu */ 792 last_queued; /* when we were last queued to run */ 793}; 794#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ 795 796#ifdef CONFIG_TASK_DELAY_ACCT 797struct task_delay_info { 798 spinlock_t lock; 799 unsigned int flags; /* Private per-task flags */ 800 801 /* For each stat XXX, add following, aligned appropriately 802 * 803 * struct timespec XXX_start, XXX_end; 804 * u64 XXX_delay; 805 * u32 XXX_count; 806 * 807 * Atomicity of updates to XXX_delay, XXX_count protected by 808 * single lock above (split into XXX_lock if contention is an issue). 809 */ 810 811 /* 812 * XXX_count is incremented on every XXX operation, the delay 813 * associated with the operation is added to XXX_delay. 814 * XXX_delay contains the accumulated delay time in nanoseconds. 815 */ 816 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ 817 u64 blkio_delay; /* wait for sync block io completion */ 818 u64 swapin_delay; /* wait for swapin block io completion */ 819 u32 blkio_count; /* total count of the number of sync block */ 820 /* io operations performed */ 821 u32 swapin_count; /* total count of the number of swapin block */ 822 /* io operations performed */ 823 824 struct timespec freepages_start, freepages_end; 825 u64 freepages_delay; /* wait for memory reclaim */ 826 u32 freepages_count; /* total count of memory reclaim */ 827}; 828#endif /* CONFIG_TASK_DELAY_ACCT */ 829 830static inline int sched_info_on(void) 831{ 832#ifdef CONFIG_SCHEDSTATS 833 return 1; 834#elif defined(CONFIG_TASK_DELAY_ACCT) 835 extern int delayacct_on; 836 return delayacct_on; 837#else 838 return 0; 839#endif 840} 841 842enum cpu_idle_type { 843 CPU_IDLE, 844 CPU_NOT_IDLE, 845 CPU_NEWLY_IDLE, 846 CPU_MAX_IDLE_TYPES 847}; 848 849/* 850 * Increase resolution of cpu_capacity calculations 851 */ 852#define SCHED_CAPACITY_SHIFT 10 853#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 854 855/* 856 * sched-domains (multiprocessor balancing) declarations: 857 */ 858#ifdef CONFIG_SMP 859#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 860#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 861#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 862#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 863#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 864#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 865#define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu power */ 866#define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ 867#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 868#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 869#define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 870#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 871#define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 872#define SD_NUMA 0x4000 /* cross-node balancing */ 873 874#ifdef CONFIG_SCHED_SMT 875static inline int cpu_smt_flags(void) 876{ 877 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; 878} 879#endif 880 881#ifdef CONFIG_SCHED_MC 882static inline int cpu_core_flags(void) 883{ 884 return SD_SHARE_PKG_RESOURCES; 885} 886#endif 887 888#ifdef CONFIG_NUMA 889static inline int cpu_numa_flags(void) 890{ 891 return SD_NUMA; 892} 893#endif 894 895struct sched_domain_attr { 896 int relax_domain_level; 897}; 898 899#define SD_ATTR_INIT (struct sched_domain_attr) { \ 900 .relax_domain_level = -1, \ 901} 902 903extern int sched_domain_level_max; 904 905struct sched_group; 906 907struct sched_domain { 908 /* These fields must be setup */ 909 struct sched_domain *parent; /* top domain must be null terminated */ 910 struct sched_domain *child; /* bottom domain must be null terminated */ 911 struct sched_group *groups; /* the balancing groups of the domain */ 912 unsigned long min_interval; /* Minimum balance interval ms */ 913 unsigned long max_interval; /* Maximum balance interval ms */ 914 unsigned int busy_factor; /* less balancing by factor if busy */ 915 unsigned int imbalance_pct; /* No balance until over watermark */ 916 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 917 unsigned int busy_idx; 918 unsigned int idle_idx; 919 unsigned int newidle_idx; 920 unsigned int wake_idx; 921 unsigned int forkexec_idx; 922 unsigned int smt_gain; 923 924 int nohz_idle; /* NOHZ IDLE status */ 925 int flags; /* See SD_* */ 926 int level; 927 928 /* Runtime fields. */ 929 unsigned long last_balance; /* init to jiffies. units in jiffies */ 930 unsigned int balance_interval; /* initialise to 1. units in ms. */ 931 unsigned int nr_balance_failed; /* initialise to 0 */ 932 933 /* idle_balance() stats */ 934 u64 max_newidle_lb_cost; 935 unsigned long next_decay_max_lb_cost; 936 937#ifdef CONFIG_SCHEDSTATS 938 /* load_balance() stats */ 939 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 940 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 941 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 942 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 943 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 944 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 945 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 946 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 947 948 /* Active load balancing */ 949 unsigned int alb_count; 950 unsigned int alb_failed; 951 unsigned int alb_pushed; 952 953 /* SD_BALANCE_EXEC stats */ 954 unsigned int sbe_count; 955 unsigned int sbe_balanced; 956 unsigned int sbe_pushed; 957 958 /* SD_BALANCE_FORK stats */ 959 unsigned int sbf_count; 960 unsigned int sbf_balanced; 961 unsigned int sbf_pushed; 962 963 /* try_to_wake_up() stats */ 964 unsigned int ttwu_wake_remote; 965 unsigned int ttwu_move_affine; 966 unsigned int ttwu_move_balance; 967#endif 968#ifdef CONFIG_SCHED_DEBUG 969 char *name; 970#endif 971 union { 972 void *private; /* used during construction */ 973 struct rcu_head rcu; /* used during destruction */ 974 }; 975 976 unsigned int span_weight; 977 /* 978 * Span of all CPUs in this domain. 979 * 980 * NOTE: this field is variable length. (Allocated dynamically 981 * by attaching extra space to the end of the structure, 982 * depending on how many CPUs the kernel has booted up with) 983 */ 984 unsigned long span[0]; 985}; 986 987static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 988{ 989 return to_cpumask(sd->span); 990} 991 992extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 993 struct sched_domain_attr *dattr_new); 994 995/* Allocate an array of sched domains, for partition_sched_domains(). */ 996cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 997void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 998 999bool cpus_share_cache(int this_cpu, int that_cpu); 1000 1001typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); 1002typedef int (*sched_domain_flags_f)(void); 1003 1004#define SDTL_OVERLAP 0x01 1005 1006struct sd_data { 1007 struct sched_domain **__percpu sd; 1008 struct sched_group **__percpu sg; 1009 struct sched_group_capacity **__percpu sgc; 1010}; 1011 1012struct sched_domain_topology_level { 1013 sched_domain_mask_f mask; 1014 sched_domain_flags_f sd_flags; 1015 int flags; 1016 int numa_level; 1017 struct sd_data data; 1018#ifdef CONFIG_SCHED_DEBUG 1019 char *name; 1020#endif 1021}; 1022 1023extern struct sched_domain_topology_level *sched_domain_topology; 1024 1025extern void set_sched_topology(struct sched_domain_topology_level *tl); 1026 1027#ifdef CONFIG_SCHED_DEBUG 1028# define SD_INIT_NAME(type) .name = #type 1029#else 1030# define SD_INIT_NAME(type) 1031#endif 1032 1033#else /* CONFIG_SMP */ 1034 1035struct sched_domain_attr; 1036 1037static inline void 1038partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1039 struct sched_domain_attr *dattr_new) 1040{ 1041} 1042 1043static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1044{ 1045 return true; 1046} 1047 1048#endif /* !CONFIG_SMP */ 1049 1050 1051struct io_context; /* See blkdev.h */ 1052 1053 1054#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1055extern void prefetch_stack(struct task_struct *t); 1056#else 1057static inline void prefetch_stack(struct task_struct *t) { } 1058#endif 1059 1060struct audit_context; /* See audit.c */ 1061struct mempolicy; 1062struct pipe_inode_info; 1063struct uts_namespace; 1064 1065struct load_weight { 1066 unsigned long weight; 1067 u32 inv_weight; 1068}; 1069 1070struct sched_avg { 1071 /* 1072 * These sums represent an infinite geometric series and so are bound 1073 * above by 1024/(1-y). Thus we only need a u32 to store them for all 1074 * choices of y < 1-2^(-32)*1024. 1075 */ 1076 u32 runnable_avg_sum, runnable_avg_period; 1077 u64 last_runnable_update; 1078 s64 decay_count; 1079 unsigned long load_avg_contrib; 1080}; 1081 1082#ifdef CONFIG_SCHEDSTATS 1083struct sched_statistics { 1084 u64 wait_start; 1085 u64 wait_max; 1086 u64 wait_count; 1087 u64 wait_sum; 1088 u64 iowait_count; 1089 u64 iowait_sum; 1090 1091 u64 sleep_start; 1092 u64 sleep_max; 1093 s64 sum_sleep_runtime; 1094 1095 u64 block_start; 1096 u64 block_max; 1097 u64 exec_max; 1098 u64 slice_max; 1099 1100 u64 nr_migrations_cold; 1101 u64 nr_failed_migrations_affine; 1102 u64 nr_failed_migrations_running; 1103 u64 nr_failed_migrations_hot; 1104 u64 nr_forced_migrations; 1105 1106 u64 nr_wakeups; 1107 u64 nr_wakeups_sync; 1108 u64 nr_wakeups_migrate; 1109 u64 nr_wakeups_local; 1110 u64 nr_wakeups_remote; 1111 u64 nr_wakeups_affine; 1112 u64 nr_wakeups_affine_attempts; 1113 u64 nr_wakeups_passive; 1114 u64 nr_wakeups_idle; 1115}; 1116#endif 1117 1118struct sched_entity { 1119 struct load_weight load; /* for load-balancing */ 1120 struct rb_node run_node; 1121 struct list_head group_node; 1122 unsigned int on_rq; 1123 1124 u64 exec_start; 1125 u64 sum_exec_runtime; 1126 u64 vruntime; 1127 u64 prev_sum_exec_runtime; 1128 1129 u64 nr_migrations; 1130 1131#ifdef CONFIG_SCHEDSTATS 1132 struct sched_statistics statistics; 1133#endif 1134 1135#ifdef CONFIG_FAIR_GROUP_SCHED 1136 int depth; 1137 struct sched_entity *parent; 1138 /* rq on which this entity is (to be) queued: */ 1139 struct cfs_rq *cfs_rq; 1140 /* rq "owned" by this entity/group: */ 1141 struct cfs_rq *my_q; 1142#endif 1143 1144#ifdef CONFIG_SMP 1145 /* Per-entity load-tracking */ 1146 struct sched_avg avg; 1147#endif 1148}; 1149 1150struct sched_rt_entity { 1151 struct list_head run_list; 1152 unsigned long timeout; 1153 unsigned long watchdog_stamp; 1154 unsigned int time_slice; 1155 1156 struct sched_rt_entity *back; 1157#ifdef CONFIG_RT_GROUP_SCHED 1158 struct sched_rt_entity *parent; 1159 /* rq on which this entity is (to be) queued: */ 1160 struct rt_rq *rt_rq; 1161 /* rq "owned" by this entity/group: */ 1162 struct rt_rq *my_q; 1163#endif 1164}; 1165 1166struct sched_dl_entity { 1167 struct rb_node rb_node; 1168 1169 /* 1170 * Original scheduling parameters. Copied here from sched_attr 1171 * during sched_setattr(), they will remain the same until 1172 * the next sched_setattr(). 1173 */ 1174 u64 dl_runtime; /* maximum runtime for each instance */ 1175 u64 dl_deadline; /* relative deadline of each instance */ 1176 u64 dl_period; /* separation of two instances (period) */ 1177 u64 dl_bw; /* dl_runtime / dl_deadline */ 1178 1179 /* 1180 * Actual scheduling parameters. Initialized with the values above, 1181 * they are continously updated during task execution. Note that 1182 * the remaining runtime could be < 0 in case we are in overrun. 1183 */ 1184 s64 runtime; /* remaining runtime for this instance */ 1185 u64 deadline; /* absolute deadline for this instance */ 1186 unsigned int flags; /* specifying the scheduler behaviour */ 1187 1188 /* 1189 * Some bool flags: 1190 * 1191 * @dl_throttled tells if we exhausted the runtime. If so, the 1192 * task has to wait for a replenishment to be performed at the 1193 * next firing of dl_timer. 1194 * 1195 * @dl_new tells if a new instance arrived. If so we must 1196 * start executing it with full runtime and reset its absolute 1197 * deadline; 1198 * 1199 * @dl_boosted tells if we are boosted due to DI. If so we are 1200 * outside bandwidth enforcement mechanism (but only until we 1201 * exit the critical section); 1202 * 1203 * @dl_yielded tells if task gave up the cpu before consuming 1204 * all its available runtime during the last job. 1205 */ 1206 int dl_throttled, dl_new, dl_boosted, dl_yielded; 1207 1208 /* 1209 * Bandwidth enforcement timer. Each -deadline task has its 1210 * own bandwidth to be enforced, thus we need one timer per task. 1211 */ 1212 struct hrtimer dl_timer; 1213}; 1214 1215struct rcu_node; 1216 1217enum perf_event_task_context { 1218 perf_invalid_context = -1, 1219 perf_hw_context = 0, 1220 perf_sw_context, 1221 perf_nr_task_contexts, 1222}; 1223 1224struct task_struct { 1225 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1226 void *stack; 1227 atomic_t usage; 1228 unsigned int flags; /* per process flags, defined below */ 1229 unsigned int ptrace; 1230 1231#ifdef CONFIG_SMP 1232 struct llist_node wake_entry; 1233 int on_cpu; 1234 struct task_struct *last_wakee; 1235 unsigned long wakee_flips; 1236 unsigned long wakee_flip_decay_ts; 1237 1238 int wake_cpu; 1239#endif 1240 int on_rq; 1241 1242 int prio, static_prio, normal_prio; 1243 unsigned int rt_priority; 1244 const struct sched_class *sched_class; 1245 struct sched_entity se; 1246 struct sched_rt_entity rt; 1247#ifdef CONFIG_CGROUP_SCHED 1248 struct task_group *sched_task_group; 1249#endif 1250 struct sched_dl_entity dl; 1251 1252#ifdef CONFIG_PREEMPT_NOTIFIERS 1253 /* list of struct preempt_notifier: */ 1254 struct hlist_head preempt_notifiers; 1255#endif 1256 1257#ifdef CONFIG_BLK_DEV_IO_TRACE 1258 unsigned int btrace_seq; 1259#endif 1260 1261 unsigned int policy; 1262 int nr_cpus_allowed; 1263 cpumask_t cpus_allowed; 1264 1265#ifdef CONFIG_PREEMPT_RCU 1266 int rcu_read_lock_nesting; 1267 char rcu_read_unlock_special; 1268 struct list_head rcu_node_entry; 1269#endif /* #ifdef CONFIG_PREEMPT_RCU */ 1270#ifdef CONFIG_TREE_PREEMPT_RCU 1271 struct rcu_node *rcu_blocked_node; 1272#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1273#ifdef CONFIG_RCU_BOOST 1274 struct rt_mutex *rcu_boost_mutex; 1275#endif /* #ifdef CONFIG_RCU_BOOST */ 1276 1277#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 1278 struct sched_info sched_info; 1279#endif 1280 1281 struct list_head tasks; 1282#ifdef CONFIG_SMP 1283 struct plist_node pushable_tasks; 1284 struct rb_node pushable_dl_tasks; 1285#endif 1286 1287 struct mm_struct *mm, *active_mm; 1288#ifdef CONFIG_COMPAT_BRK 1289 unsigned brk_randomized:1; 1290#endif 1291 /* per-thread vma caching */ 1292 u32 vmacache_seqnum; 1293 struct vm_area_struct *vmacache[VMACACHE_SIZE]; 1294#if defined(SPLIT_RSS_COUNTING) 1295 struct task_rss_stat rss_stat; 1296#endif 1297/* task state */ 1298 int exit_state; 1299 int exit_code, exit_signal; 1300 int pdeath_signal; /* The signal sent when the parent dies */ 1301 unsigned int jobctl; /* JOBCTL_*, siglock protected */ 1302 1303 /* Used for emulating ABI behavior of previous Linux versions */ 1304 unsigned int personality; 1305 1306 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1307 * execve */ 1308 unsigned in_iowait:1; 1309 1310 /* task may not gain privileges */ 1311 unsigned no_new_privs:1; 1312 1313 /* Revert to default priority/policy when forking */ 1314 unsigned sched_reset_on_fork:1; 1315 unsigned sched_contributes_to_load:1; 1316 1317 pid_t pid; 1318 pid_t tgid; 1319 1320#ifdef CONFIG_CC_STACKPROTECTOR 1321 /* Canary value for the -fstack-protector gcc feature */ 1322 unsigned long stack_canary; 1323#endif 1324 /* 1325 * pointers to (original) parent process, youngest child, younger sibling, 1326 * older sibling, respectively. (p->father can be replaced with 1327 * p->real_parent->pid) 1328 */ 1329 struct task_struct __rcu *real_parent; /* real parent process */ 1330 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1331 /* 1332 * children/sibling forms the list of my natural children 1333 */ 1334 struct list_head children; /* list of my children */ 1335 struct list_head sibling; /* linkage in my parent's children list */ 1336 struct task_struct *group_leader; /* threadgroup leader */ 1337 1338 /* 1339 * ptraced is the list of tasks this task is using ptrace on. 1340 * This includes both natural children and PTRACE_ATTACH targets. 1341 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1342 */ 1343 struct list_head ptraced; 1344 struct list_head ptrace_entry; 1345 1346 /* PID/PID hash table linkage. */ 1347 struct pid_link pids[PIDTYPE_MAX]; 1348 struct list_head thread_group; 1349 struct list_head thread_node; 1350 1351 struct completion *vfork_done; /* for vfork() */ 1352 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1353 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1354 1355 cputime_t utime, stime, utimescaled, stimescaled; 1356 cputime_t gtime; 1357#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 1358 struct cputime prev_cputime; 1359#endif 1360#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1361 seqlock_t vtime_seqlock; 1362 unsigned long long vtime_snap; 1363 enum { 1364 VTIME_SLEEPING = 0, 1365 VTIME_USER, 1366 VTIME_SYS, 1367 } vtime_snap_whence; 1368#endif 1369 unsigned long nvcsw, nivcsw; /* context switch counts */ 1370 struct timespec start_time; /* monotonic time */ 1371 struct timespec real_start_time; /* boot based time */ 1372/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1373 unsigned long min_flt, maj_flt; 1374 1375 struct task_cputime cputime_expires; 1376 struct list_head cpu_timers[3]; 1377 1378/* process credentials */ 1379 const struct cred __rcu *real_cred; /* objective and real subjective task 1380 * credentials (COW) */ 1381 const struct cred __rcu *cred; /* effective (overridable) subjective task 1382 * credentials (COW) */ 1383 char comm[TASK_COMM_LEN]; /* executable name excluding path 1384 - access with [gs]et_task_comm (which lock 1385 it with task_lock()) 1386 - initialized normally by setup_new_exec */ 1387/* file system info */ 1388 int link_count, total_link_count; 1389#ifdef CONFIG_SYSVIPC 1390/* ipc stuff */ 1391 struct sysv_sem sysvsem; 1392#endif 1393#ifdef CONFIG_DETECT_HUNG_TASK 1394/* hung task detection */ 1395 unsigned long last_switch_count; 1396#endif 1397/* CPU-specific state of this task */ 1398 struct thread_struct thread; 1399/* filesystem information */ 1400 struct fs_struct *fs; 1401/* open file information */ 1402 struct files_struct *files; 1403/* namespaces */ 1404 struct nsproxy *nsproxy; 1405/* signal handlers */ 1406 struct signal_struct *signal; 1407 struct sighand_struct *sighand; 1408 1409 sigset_t blocked, real_blocked; 1410 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1411 struct sigpending pending; 1412 1413 unsigned long sas_ss_sp; 1414 size_t sas_ss_size; 1415 int (*notifier)(void *priv); 1416 void *notifier_data; 1417 sigset_t *notifier_mask; 1418 struct callback_head *task_works; 1419 1420 struct audit_context *audit_context; 1421#ifdef CONFIG_AUDITSYSCALL 1422 kuid_t loginuid; 1423 unsigned int sessionid; 1424#endif 1425 struct seccomp seccomp; 1426 1427/* Thread group tracking */ 1428 u32 parent_exec_id; 1429 u32 self_exec_id; 1430/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1431 * mempolicy */ 1432 spinlock_t alloc_lock; 1433 1434 /* Protection of the PI data structures: */ 1435 raw_spinlock_t pi_lock; 1436 1437#ifdef CONFIG_RT_MUTEXES 1438 /* PI waiters blocked on a rt_mutex held by this task */ 1439 struct rb_root pi_waiters; 1440 struct rb_node *pi_waiters_leftmost; 1441 /* Deadlock detection and priority inheritance handling */ 1442 struct rt_mutex_waiter *pi_blocked_on; 1443 /* Top pi_waiters task */ 1444 struct task_struct *pi_top_task; 1445#endif 1446 1447#ifdef CONFIG_DEBUG_MUTEXES 1448 /* mutex deadlock detection */ 1449 struct mutex_waiter *blocked_on; 1450#endif 1451#ifdef CONFIG_TRACE_IRQFLAGS 1452 unsigned int irq_events; 1453 unsigned long hardirq_enable_ip; 1454 unsigned long hardirq_disable_ip; 1455 unsigned int hardirq_enable_event; 1456 unsigned int hardirq_disable_event; 1457 int hardirqs_enabled; 1458 int hardirq_context; 1459 unsigned long softirq_disable_ip; 1460 unsigned long softirq_enable_ip; 1461 unsigned int softirq_disable_event; 1462 unsigned int softirq_enable_event; 1463 int softirqs_enabled; 1464 int softirq_context; 1465#endif 1466#ifdef CONFIG_LOCKDEP 1467# define MAX_LOCK_DEPTH 48UL 1468 u64 curr_chain_key; 1469 int lockdep_depth; 1470 unsigned int lockdep_recursion; 1471 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1472 gfp_t lockdep_reclaim_gfp; 1473#endif 1474 1475/* journalling filesystem info */ 1476 void *journal_info; 1477 1478/* stacked block device info */ 1479 struct bio_list *bio_list; 1480 1481#ifdef CONFIG_BLOCK 1482/* stack plugging */ 1483 struct blk_plug *plug; 1484#endif 1485 1486/* VM state */ 1487 struct reclaim_state *reclaim_state; 1488 1489 struct backing_dev_info *backing_dev_info; 1490 1491 struct io_context *io_context; 1492 1493 unsigned long ptrace_message; 1494 siginfo_t *last_siginfo; /* For ptrace use. */ 1495 struct task_io_accounting ioac; 1496#if defined(CONFIG_TASK_XACCT) 1497 u64 acct_rss_mem1; /* accumulated rss usage */ 1498 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1499 cputime_t acct_timexpd; /* stime + utime since last update */ 1500#endif 1501#ifdef CONFIG_CPUSETS 1502 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1503 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1504 int cpuset_mem_spread_rotor; 1505 int cpuset_slab_spread_rotor; 1506#endif 1507#ifdef CONFIG_CGROUPS 1508 /* Control Group info protected by css_set_lock */ 1509 struct css_set __rcu *cgroups; 1510 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1511 struct list_head cg_list; 1512#endif 1513#ifdef CONFIG_FUTEX 1514 struct robust_list_head __user *robust_list; 1515#ifdef CONFIG_COMPAT 1516 struct compat_robust_list_head __user *compat_robust_list; 1517#endif 1518 struct list_head pi_state_list; 1519 struct futex_pi_state *pi_state_cache; 1520#endif 1521#ifdef CONFIG_PERF_EVENTS 1522 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1523 struct mutex perf_event_mutex; 1524 struct list_head perf_event_list; 1525#endif 1526#ifdef CONFIG_DEBUG_PREEMPT 1527 unsigned long preempt_disable_ip; 1528#endif 1529#ifdef CONFIG_NUMA 1530 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1531 short il_next; 1532 short pref_node_fork; 1533#endif 1534#ifdef CONFIG_NUMA_BALANCING 1535 int numa_scan_seq; 1536 unsigned int numa_scan_period; 1537 unsigned int numa_scan_period_max; 1538 int numa_preferred_nid; 1539 unsigned long numa_migrate_retry; 1540 u64 node_stamp; /* migration stamp */ 1541 u64 last_task_numa_placement; 1542 u64 last_sum_exec_runtime; 1543 struct callback_head numa_work; 1544 1545 struct list_head numa_entry; 1546 struct numa_group *numa_group; 1547 1548 /* 1549 * Exponential decaying average of faults on a per-node basis. 1550 * Scheduling placement decisions are made based on the these counts. 1551 * The values remain static for the duration of a PTE scan 1552 */ 1553 unsigned long *numa_faults_memory; 1554 unsigned long total_numa_faults; 1555 1556 /* 1557 * numa_faults_buffer records faults per node during the current 1558 * scan window. When the scan completes, the counts in 1559 * numa_faults_memory decay and these values are copied. 1560 */ 1561 unsigned long *numa_faults_buffer_memory; 1562 1563 /* 1564 * Track the nodes the process was running on when a NUMA hinting 1565 * fault was incurred. 1566 */ 1567 unsigned long *numa_faults_cpu; 1568 unsigned long *numa_faults_buffer_cpu; 1569 1570 /* 1571 * numa_faults_locality tracks if faults recorded during the last 1572 * scan window were remote/local. The task scan period is adapted 1573 * based on the locality of the faults with different weights 1574 * depending on whether they were shared or private faults 1575 */ 1576 unsigned long numa_faults_locality[2]; 1577 1578 unsigned long numa_pages_migrated; 1579#endif /* CONFIG_NUMA_BALANCING */ 1580 1581 struct rcu_head rcu; 1582 1583 /* 1584 * cache last used pipe for splice 1585 */ 1586 struct pipe_inode_info *splice_pipe; 1587 1588 struct page_frag task_frag; 1589 1590#ifdef CONFIG_TASK_DELAY_ACCT 1591 struct task_delay_info *delays; 1592#endif 1593#ifdef CONFIG_FAULT_INJECTION 1594 int make_it_fail; 1595#endif 1596 /* 1597 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1598 * balance_dirty_pages() for some dirty throttling pause 1599 */ 1600 int nr_dirtied; 1601 int nr_dirtied_pause; 1602 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1603 1604#ifdef CONFIG_LATENCYTOP 1605 int latency_record_count; 1606 struct latency_record latency_record[LT_SAVECOUNT]; 1607#endif 1608 /* 1609 * time slack values; these are used to round up poll() and 1610 * select() etc timeout values. These are in nanoseconds. 1611 */ 1612 unsigned long timer_slack_ns; 1613 unsigned long default_timer_slack_ns; 1614 1615#ifdef CONFIG_FUNCTION_GRAPH_TRACER 1616 /* Index of current stored address in ret_stack */ 1617 int curr_ret_stack; 1618 /* Stack of return addresses for return function tracing */ 1619 struct ftrace_ret_stack *ret_stack; 1620 /* time stamp for last schedule */ 1621 unsigned long long ftrace_timestamp; 1622 /* 1623 * Number of functions that haven't been traced 1624 * because of depth overrun. 1625 */ 1626 atomic_t trace_overrun; 1627 /* Pause for the tracing */ 1628 atomic_t tracing_graph_pause; 1629#endif 1630#ifdef CONFIG_TRACING 1631 /* state flags for use by tracers */ 1632 unsigned long trace; 1633 /* bitmask and counter of trace recursion */ 1634 unsigned long trace_recursion; 1635#endif /* CONFIG_TRACING */ 1636#ifdef CONFIG_MEMCG /* memcg uses this to do batch job */ 1637 struct memcg_batch_info { 1638 int do_batch; /* incremented when batch uncharge started */ 1639 struct mem_cgroup *memcg; /* target memcg of uncharge */ 1640 unsigned long nr_pages; /* uncharged usage */ 1641 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ 1642 } memcg_batch; 1643 unsigned int memcg_kmem_skip_account; 1644 struct memcg_oom_info { 1645 struct mem_cgroup *memcg; 1646 gfp_t gfp_mask; 1647 int order; 1648 unsigned int may_oom:1; 1649 } memcg_oom; 1650#endif 1651#ifdef CONFIG_UPROBES 1652 struct uprobe_task *utask; 1653#endif 1654#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1655 unsigned int sequential_io; 1656 unsigned int sequential_io_avg; 1657#endif 1658}; 1659 1660/* Future-safe accessor for struct task_struct's cpus_allowed. */ 1661#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1662 1663#define TNF_MIGRATED 0x01 1664#define TNF_NO_GROUP 0x02 1665#define TNF_SHARED 0x04 1666#define TNF_FAULT_LOCAL 0x08 1667 1668#ifdef CONFIG_NUMA_BALANCING 1669extern void task_numa_fault(int last_node, int node, int pages, int flags); 1670extern pid_t task_numa_group_id(struct task_struct *p); 1671extern void set_numabalancing_state(bool enabled); 1672extern void task_numa_free(struct task_struct *p); 1673extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page, 1674 int src_nid, int dst_cpu); 1675#else 1676static inline void task_numa_fault(int last_node, int node, int pages, 1677 int flags) 1678{ 1679} 1680static inline pid_t task_numa_group_id(struct task_struct *p) 1681{ 1682 return 0; 1683} 1684static inline void set_numabalancing_state(bool enabled) 1685{ 1686} 1687static inline void task_numa_free(struct task_struct *p) 1688{ 1689} 1690static inline bool should_numa_migrate_memory(struct task_struct *p, 1691 struct page *page, int src_nid, int dst_cpu) 1692{ 1693 return true; 1694} 1695#endif 1696 1697static inline struct pid *task_pid(struct task_struct *task) 1698{ 1699 return task->pids[PIDTYPE_PID].pid; 1700} 1701 1702static inline struct pid *task_tgid(struct task_struct *task) 1703{ 1704 return task->group_leader->pids[PIDTYPE_PID].pid; 1705} 1706 1707/* 1708 * Without tasklist or rcu lock it is not safe to dereference 1709 * the result of task_pgrp/task_session even if task == current, 1710 * we can race with another thread doing sys_setsid/sys_setpgid. 1711 */ 1712static inline struct pid *task_pgrp(struct task_struct *task) 1713{ 1714 return task->group_leader->pids[PIDTYPE_PGID].pid; 1715} 1716 1717static inline struct pid *task_session(struct task_struct *task) 1718{ 1719 return task->group_leader->pids[PIDTYPE_SID].pid; 1720} 1721 1722struct pid_namespace; 1723 1724/* 1725 * the helpers to get the task's different pids as they are seen 1726 * from various namespaces 1727 * 1728 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1729 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1730 * current. 1731 * task_xid_nr_ns() : id seen from the ns specified; 1732 * 1733 * set_task_vxid() : assigns a virtual id to a task; 1734 * 1735 * see also pid_nr() etc in include/linux/pid.h 1736 */ 1737pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1738 struct pid_namespace *ns); 1739 1740static inline pid_t task_pid_nr(struct task_struct *tsk) 1741{ 1742 return tsk->pid; 1743} 1744 1745static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1746 struct pid_namespace *ns) 1747{ 1748 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1749} 1750 1751static inline pid_t task_pid_vnr(struct task_struct *tsk) 1752{ 1753 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1754} 1755 1756 1757static inline pid_t task_tgid_nr(struct task_struct *tsk) 1758{ 1759 return tsk->tgid; 1760} 1761 1762pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1763 1764static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1765{ 1766 return pid_vnr(task_tgid(tsk)); 1767} 1768 1769 1770static inline int pid_alive(const struct task_struct *p); 1771static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 1772{ 1773 pid_t pid = 0; 1774 1775 rcu_read_lock(); 1776 if (pid_alive(tsk)) 1777 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 1778 rcu_read_unlock(); 1779 1780 return pid; 1781} 1782 1783static inline pid_t task_ppid_nr(const struct task_struct *tsk) 1784{ 1785 return task_ppid_nr_ns(tsk, &init_pid_ns); 1786} 1787 1788static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1789 struct pid_namespace *ns) 1790{ 1791 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1792} 1793 1794static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1795{ 1796 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1797} 1798 1799 1800static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1801 struct pid_namespace *ns) 1802{ 1803 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1804} 1805 1806static inline pid_t task_session_vnr(struct task_struct *tsk) 1807{ 1808 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1809} 1810 1811/* obsolete, do not use */ 1812static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1813{ 1814 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1815} 1816 1817/** 1818 * pid_alive - check that a task structure is not stale 1819 * @p: Task structure to be checked. 1820 * 1821 * Test if a process is not yet dead (at most zombie state) 1822 * If pid_alive fails, then pointers within the task structure 1823 * can be stale and must not be dereferenced. 1824 * 1825 * Return: 1 if the process is alive. 0 otherwise. 1826 */ 1827static inline int pid_alive(const struct task_struct *p) 1828{ 1829 return p->pids[PIDTYPE_PID].pid != NULL; 1830} 1831 1832/** 1833 * is_global_init - check if a task structure is init 1834 * @tsk: Task structure to be checked. 1835 * 1836 * Check if a task structure is the first user space task the kernel created. 1837 * 1838 * Return: 1 if the task structure is init. 0 otherwise. 1839 */ 1840static inline int is_global_init(struct task_struct *tsk) 1841{ 1842 return tsk->pid == 1; 1843} 1844 1845extern struct pid *cad_pid; 1846 1847extern void free_task(struct task_struct *tsk); 1848#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1849 1850extern void __put_task_struct(struct task_struct *t); 1851 1852static inline void put_task_struct(struct task_struct *t) 1853{ 1854 if (atomic_dec_and_test(&t->usage)) 1855 __put_task_struct(t); 1856} 1857 1858#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1859extern void task_cputime(struct task_struct *t, 1860 cputime_t *utime, cputime_t *stime); 1861extern void task_cputime_scaled(struct task_struct *t, 1862 cputime_t *utimescaled, cputime_t *stimescaled); 1863extern cputime_t task_gtime(struct task_struct *t); 1864#else 1865static inline void task_cputime(struct task_struct *t, 1866 cputime_t *utime, cputime_t *stime) 1867{ 1868 if (utime) 1869 *utime = t->utime; 1870 if (stime) 1871 *stime = t->stime; 1872} 1873 1874static inline void task_cputime_scaled(struct task_struct *t, 1875 cputime_t *utimescaled, 1876 cputime_t *stimescaled) 1877{ 1878 if (utimescaled) 1879 *utimescaled = t->utimescaled; 1880 if (stimescaled) 1881 *stimescaled = t->stimescaled; 1882} 1883 1884static inline cputime_t task_gtime(struct task_struct *t) 1885{ 1886 return t->gtime; 1887} 1888#endif 1889extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1890extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1891 1892/* 1893 * Per process flags 1894 */ 1895#define PF_EXITING 0x00000004 /* getting shut down */ 1896#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1897#define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 1898#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1899#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1900#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 1901#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1902#define PF_DUMPCORE 0x00000200 /* dumped core */ 1903#define PF_SIGNALED 0x00000400 /* killed by a signal */ 1904#define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1905#define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 1906#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1907#define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 1908#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1909#define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1910#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1911#define PF_KSWAPD 0x00040000 /* I am kswapd */ 1912#define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 1913#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1914#define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1915#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1916#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1917#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ 1918#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ 1919#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 1920#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1921#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1922#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1923#define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 1924 1925/* 1926 * Only the _current_ task can read/write to tsk->flags, but other 1927 * tasks can access tsk->flags in readonly mode for example 1928 * with tsk_used_math (like during threaded core dumping). 1929 * There is however an exception to this rule during ptrace 1930 * or during fork: the ptracer task is allowed to write to the 1931 * child->flags of its traced child (same goes for fork, the parent 1932 * can write to the child->flags), because we're guaranteed the 1933 * child is not running and in turn not changing child->flags 1934 * at the same time the parent does it. 1935 */ 1936#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1937#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1938#define clear_used_math() clear_stopped_child_used_math(current) 1939#define set_used_math() set_stopped_child_used_math(current) 1940#define conditional_stopped_child_used_math(condition, child) \ 1941 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1942#define conditional_used_math(condition) \ 1943 conditional_stopped_child_used_math(condition, current) 1944#define copy_to_stopped_child_used_math(child) \ 1945 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1946/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1947#define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1948#define used_math() tsk_used_math(current) 1949 1950/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags */ 1951static inline gfp_t memalloc_noio_flags(gfp_t flags) 1952{ 1953 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 1954 flags &= ~__GFP_IO; 1955 return flags; 1956} 1957 1958static inline unsigned int memalloc_noio_save(void) 1959{ 1960 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 1961 current->flags |= PF_MEMALLOC_NOIO; 1962 return flags; 1963} 1964 1965static inline void memalloc_noio_restore(unsigned int flags) 1966{ 1967 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 1968} 1969 1970/* 1971 * task->jobctl flags 1972 */ 1973#define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 1974 1975#define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 1976#define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 1977#define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 1978#define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 1979#define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 1980#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 1981#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 1982 1983#define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) 1984#define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) 1985#define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) 1986#define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) 1987#define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) 1988#define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) 1989#define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) 1990 1991#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 1992#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 1993 1994extern bool task_set_jobctl_pending(struct task_struct *task, 1995 unsigned int mask); 1996extern void task_clear_jobctl_trapping(struct task_struct *task); 1997extern void task_clear_jobctl_pending(struct task_struct *task, 1998 unsigned int mask); 1999 2000#ifdef CONFIG_PREEMPT_RCU 2001 2002#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */ 2003#define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */ 2004 2005static inline void rcu_copy_process(struct task_struct *p) 2006{ 2007 p->rcu_read_lock_nesting = 0; 2008 p->rcu_read_unlock_special = 0; 2009#ifdef CONFIG_TREE_PREEMPT_RCU 2010 p->rcu_blocked_node = NULL; 2011#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 2012#ifdef CONFIG_RCU_BOOST 2013 p->rcu_boost_mutex = NULL; 2014#endif /* #ifdef CONFIG_RCU_BOOST */ 2015 INIT_LIST_HEAD(&p->rcu_node_entry); 2016} 2017 2018#else 2019 2020static inline void rcu_copy_process(struct task_struct *p) 2021{ 2022} 2023 2024#endif 2025 2026static inline void tsk_restore_flags(struct task_struct *task, 2027 unsigned long orig_flags, unsigned long flags) 2028{ 2029 task->flags &= ~flags; 2030 task->flags |= orig_flags & flags; 2031} 2032 2033#ifdef CONFIG_SMP 2034extern void do_set_cpus_allowed(struct task_struct *p, 2035 const struct cpumask *new_mask); 2036 2037extern int set_cpus_allowed_ptr(struct task_struct *p, 2038 const struct cpumask *new_mask); 2039#else 2040static inline void do_set_cpus_allowed(struct task_struct *p, 2041 const struct cpumask *new_mask) 2042{ 2043} 2044static inline int set_cpus_allowed_ptr(struct task_struct *p, 2045 const struct cpumask *new_mask) 2046{ 2047 if (!cpumask_test_cpu(0, new_mask)) 2048 return -EINVAL; 2049 return 0; 2050} 2051#endif 2052 2053#ifdef CONFIG_NO_HZ_COMMON 2054void calc_load_enter_idle(void); 2055void calc_load_exit_idle(void); 2056#else 2057static inline void calc_load_enter_idle(void) { } 2058static inline void calc_load_exit_idle(void) { } 2059#endif /* CONFIG_NO_HZ_COMMON */ 2060 2061#ifndef CONFIG_CPUMASK_OFFSTACK 2062static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 2063{ 2064 return set_cpus_allowed_ptr(p, &new_mask); 2065} 2066#endif 2067 2068/* 2069 * Do not use outside of architecture code which knows its limitations. 2070 * 2071 * sched_clock() has no promise of monotonicity or bounded drift between 2072 * CPUs, use (which you should not) requires disabling IRQs. 2073 * 2074 * Please use one of the three interfaces below. 2075 */ 2076extern unsigned long long notrace sched_clock(void); 2077/* 2078 * See the comment in kernel/sched/clock.c 2079 */ 2080extern u64 cpu_clock(int cpu); 2081extern u64 local_clock(void); 2082extern u64 sched_clock_cpu(int cpu); 2083 2084 2085extern void sched_clock_init(void); 2086 2087#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2088static inline void sched_clock_tick(void) 2089{ 2090} 2091 2092static inline void sched_clock_idle_sleep_event(void) 2093{ 2094} 2095 2096static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 2097{ 2098} 2099#else 2100/* 2101 * Architectures can set this to 1 if they have specified 2102 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 2103 * but then during bootup it turns out that sched_clock() 2104 * is reliable after all: 2105 */ 2106extern int sched_clock_stable(void); 2107extern void set_sched_clock_stable(void); 2108extern void clear_sched_clock_stable(void); 2109 2110extern void sched_clock_tick(void); 2111extern void sched_clock_idle_sleep_event(void); 2112extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2113#endif 2114 2115#ifdef CONFIG_IRQ_TIME_ACCOUNTING 2116/* 2117 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 2118 * The reason for this explicit opt-in is not to have perf penalty with 2119 * slow sched_clocks. 2120 */ 2121extern void enable_sched_clock_irqtime(void); 2122extern void disable_sched_clock_irqtime(void); 2123#else 2124static inline void enable_sched_clock_irqtime(void) {} 2125static inline void disable_sched_clock_irqtime(void) {} 2126#endif 2127 2128extern unsigned long long 2129task_sched_runtime(struct task_struct *task); 2130 2131/* sched_exec is called by processes performing an exec */ 2132#ifdef CONFIG_SMP 2133extern void sched_exec(void); 2134#else 2135#define sched_exec() {} 2136#endif 2137 2138extern void sched_clock_idle_sleep_event(void); 2139extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2140 2141#ifdef CONFIG_HOTPLUG_CPU 2142extern void idle_task_exit(void); 2143#else 2144static inline void idle_task_exit(void) {} 2145#endif 2146 2147#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 2148extern void wake_up_nohz_cpu(int cpu); 2149#else 2150static inline void wake_up_nohz_cpu(int cpu) { } 2151#endif 2152 2153#ifdef CONFIG_NO_HZ_FULL 2154extern bool sched_can_stop_tick(void); 2155extern u64 scheduler_tick_max_deferment(void); 2156#else 2157static inline bool sched_can_stop_tick(void) { return false; } 2158#endif 2159 2160#ifdef CONFIG_SCHED_AUTOGROUP 2161extern void sched_autogroup_create_attach(struct task_struct *p); 2162extern void sched_autogroup_detach(struct task_struct *p); 2163extern void sched_autogroup_fork(struct signal_struct *sig); 2164extern void sched_autogroup_exit(struct signal_struct *sig); 2165#ifdef CONFIG_PROC_FS 2166extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2167extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2168#endif 2169#else 2170static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2171static inline void sched_autogroup_detach(struct task_struct *p) { } 2172static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2173static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2174#endif 2175 2176extern int yield_to(struct task_struct *p, bool preempt); 2177extern void set_user_nice(struct task_struct *p, long nice); 2178extern int task_prio(const struct task_struct *p); 2179/** 2180 * task_nice - return the nice value of a given task. 2181 * @p: the task in question. 2182 * 2183 * Return: The nice value [ -20 ... 0 ... 19 ]. 2184 */ 2185static inline int task_nice(const struct task_struct *p) 2186{ 2187 return PRIO_TO_NICE((p)->static_prio); 2188} 2189extern int can_nice(const struct task_struct *p, const int nice); 2190extern int task_curr(const struct task_struct *p); 2191extern int idle_cpu(int cpu); 2192extern int sched_setscheduler(struct task_struct *, int, 2193 const struct sched_param *); 2194extern int sched_setscheduler_nocheck(struct task_struct *, int, 2195 const struct sched_param *); 2196extern int sched_setattr(struct task_struct *, 2197 const struct sched_attr *); 2198extern struct task_struct *idle_task(int cpu); 2199/** 2200 * is_idle_task - is the specified task an idle task? 2201 * @p: the task in question. 2202 * 2203 * Return: 1 if @p is an idle task. 0 otherwise. 2204 */ 2205static inline bool is_idle_task(const struct task_struct *p) 2206{ 2207 return p->pid == 0; 2208} 2209extern struct task_struct *curr_task(int cpu); 2210extern void set_curr_task(int cpu, struct task_struct *p); 2211 2212void yield(void); 2213 2214/* 2215 * The default (Linux) execution domain. 2216 */ 2217extern struct exec_domain default_exec_domain; 2218 2219union thread_union { 2220 struct thread_info thread_info; 2221 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2222}; 2223 2224#ifndef __HAVE_ARCH_KSTACK_END 2225static inline int kstack_end(void *addr) 2226{ 2227 /* Reliable end of stack detection: 2228 * Some APM bios versions misalign the stack 2229 */ 2230 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2231} 2232#endif 2233 2234extern union thread_union init_thread_union; 2235extern struct task_struct init_task; 2236 2237extern struct mm_struct init_mm; 2238 2239extern struct pid_namespace init_pid_ns; 2240 2241/* 2242 * find a task by one of its numerical ids 2243 * 2244 * find_task_by_pid_ns(): 2245 * finds a task by its pid in the specified namespace 2246 * find_task_by_vpid(): 2247 * finds a task by its virtual pid 2248 * 2249 * see also find_vpid() etc in include/linux/pid.h 2250 */ 2251 2252extern struct task_struct *find_task_by_vpid(pid_t nr); 2253extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2254 struct pid_namespace *ns); 2255 2256/* per-UID process charging. */ 2257extern struct user_struct * alloc_uid(kuid_t); 2258static inline struct user_struct *get_uid(struct user_struct *u) 2259{ 2260 atomic_inc(&u->__count); 2261 return u; 2262} 2263extern void free_uid(struct user_struct *); 2264 2265#include <asm/current.h> 2266 2267extern void xtime_update(unsigned long ticks); 2268 2269extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2270extern int wake_up_process(struct task_struct *tsk); 2271extern void wake_up_new_task(struct task_struct *tsk); 2272#ifdef CONFIG_SMP 2273 extern void kick_process(struct task_struct *tsk); 2274#else 2275 static inline void kick_process(struct task_struct *tsk) { } 2276#endif 2277extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 2278extern void sched_dead(struct task_struct *p); 2279 2280extern void proc_caches_init(void); 2281extern void flush_signals(struct task_struct *); 2282extern void __flush_signals(struct task_struct *); 2283extern void ignore_signals(struct task_struct *); 2284extern void flush_signal_handlers(struct task_struct *, int force_default); 2285extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2286 2287static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2288{ 2289 unsigned long flags; 2290 int ret; 2291 2292 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2293 ret = dequeue_signal(tsk, mask, info); 2294 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2295 2296 return ret; 2297} 2298 2299extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2300 sigset_t *mask); 2301extern void unblock_all_signals(void); 2302extern void release_task(struct task_struct * p); 2303extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2304extern int force_sigsegv(int, struct task_struct *); 2305extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2306extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2307extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2308extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2309 const struct cred *, u32); 2310extern int kill_pgrp(struct pid *pid, int sig, int priv); 2311extern int kill_pid(struct pid *pid, int sig, int priv); 2312extern int kill_proc_info(int, struct siginfo *, pid_t); 2313extern __must_check bool do_notify_parent(struct task_struct *, int); 2314extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2315extern void force_sig(int, struct task_struct *); 2316extern int send_sig(int, struct task_struct *, int); 2317extern int zap_other_threads(struct task_struct *p); 2318extern struct sigqueue *sigqueue_alloc(void); 2319extern void sigqueue_free(struct sigqueue *); 2320extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2321extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2322 2323static inline void restore_saved_sigmask(void) 2324{ 2325 if (test_and_clear_restore_sigmask()) 2326 __set_current_blocked(&current->saved_sigmask); 2327} 2328 2329static inline sigset_t *sigmask_to_save(void) 2330{ 2331 sigset_t *res = &current->blocked; 2332 if (unlikely(test_restore_sigmask())) 2333 res = &current->saved_sigmask; 2334 return res; 2335} 2336 2337static inline int kill_cad_pid(int sig, int priv) 2338{ 2339 return kill_pid(cad_pid, sig, priv); 2340} 2341 2342/* These can be the second arg to send_sig_info/send_group_sig_info. */ 2343#define SEND_SIG_NOINFO ((struct siginfo *) 0) 2344#define SEND_SIG_PRIV ((struct siginfo *) 1) 2345#define SEND_SIG_FORCED ((struct siginfo *) 2) 2346 2347/* 2348 * True if we are on the alternate signal stack. 2349 */ 2350static inline int on_sig_stack(unsigned long sp) 2351{ 2352#ifdef CONFIG_STACK_GROWSUP 2353 return sp >= current->sas_ss_sp && 2354 sp - current->sas_ss_sp < current->sas_ss_size; 2355#else 2356 return sp > current->sas_ss_sp && 2357 sp - current->sas_ss_sp <= current->sas_ss_size; 2358#endif 2359} 2360 2361static inline int sas_ss_flags(unsigned long sp) 2362{ 2363 return (current->sas_ss_size == 0 ? SS_DISABLE 2364 : on_sig_stack(sp) ? SS_ONSTACK : 0); 2365} 2366 2367static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2368{ 2369 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2370#ifdef CONFIG_STACK_GROWSUP 2371 return current->sas_ss_sp; 2372#else 2373 return current->sas_ss_sp + current->sas_ss_size; 2374#endif 2375 return sp; 2376} 2377 2378/* 2379 * Routines for handling mm_structs 2380 */ 2381extern struct mm_struct * mm_alloc(void); 2382 2383/* mmdrop drops the mm and the page tables */ 2384extern void __mmdrop(struct mm_struct *); 2385static inline void mmdrop(struct mm_struct * mm) 2386{ 2387 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2388 __mmdrop(mm); 2389} 2390 2391/* mmput gets rid of the mappings and all user-space */ 2392extern void mmput(struct mm_struct *); 2393/* Grab a reference to a task's mm, if it is not already going away */ 2394extern struct mm_struct *get_task_mm(struct task_struct *task); 2395/* 2396 * Grab a reference to a task's mm, if it is not already going away 2397 * and ptrace_may_access with the mode parameter passed to it 2398 * succeeds. 2399 */ 2400extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2401/* Remove the current tasks stale references to the old mm_struct */ 2402extern void mm_release(struct task_struct *, struct mm_struct *); 2403 2404extern int copy_thread(unsigned long, unsigned long, unsigned long, 2405 struct task_struct *); 2406extern void flush_thread(void); 2407extern void exit_thread(void); 2408 2409extern void exit_files(struct task_struct *); 2410extern void __cleanup_sighand(struct sighand_struct *); 2411 2412extern void exit_itimers(struct signal_struct *); 2413extern void flush_itimer_signals(void); 2414 2415extern void do_group_exit(int); 2416 2417extern int do_execve(struct filename *, 2418 const char __user * const __user *, 2419 const char __user * const __user *); 2420extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2421struct task_struct *fork_idle(int); 2422extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2423 2424extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 2425static inline void set_task_comm(struct task_struct *tsk, const char *from) 2426{ 2427 __set_task_comm(tsk, from, false); 2428} 2429extern char *get_task_comm(char *to, struct task_struct *tsk); 2430 2431#ifdef CONFIG_SMP 2432void scheduler_ipi(void); 2433extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2434#else 2435static inline void scheduler_ipi(void) { } 2436static inline unsigned long wait_task_inactive(struct task_struct *p, 2437 long match_state) 2438{ 2439 return 1; 2440} 2441#endif 2442 2443#define next_task(p) \ 2444 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2445 2446#define for_each_process(p) \ 2447 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2448 2449extern bool current_is_single_threaded(void); 2450 2451/* 2452 * Careful: do_each_thread/while_each_thread is a double loop so 2453 * 'break' will not work as expected - use goto instead. 2454 */ 2455#define do_each_thread(g, t) \ 2456 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2457 2458#define while_each_thread(g, t) \ 2459 while ((t = next_thread(t)) != g) 2460 2461#define __for_each_thread(signal, t) \ 2462 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) 2463 2464#define for_each_thread(p, t) \ 2465 __for_each_thread((p)->signal, t) 2466 2467/* Careful: this is a double loop, 'break' won't work as expected. */ 2468#define for_each_process_thread(p, t) \ 2469 for_each_process(p) for_each_thread(p, t) 2470 2471static inline int get_nr_threads(struct task_struct *tsk) 2472{ 2473 return tsk->signal->nr_threads; 2474} 2475 2476static inline bool thread_group_leader(struct task_struct *p) 2477{ 2478 return p->exit_signal >= 0; 2479} 2480 2481/* Do to the insanities of de_thread it is possible for a process 2482 * to have the pid of the thread group leader without actually being 2483 * the thread group leader. For iteration through the pids in proc 2484 * all we care about is that we have a task with the appropriate 2485 * pid, we don't actually care if we have the right task. 2486 */ 2487static inline bool has_group_leader_pid(struct task_struct *p) 2488{ 2489 return task_pid(p) == p->signal->leader_pid; 2490} 2491 2492static inline 2493bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 2494{ 2495 return p1->signal == p2->signal; 2496} 2497 2498static inline struct task_struct *next_thread(const struct task_struct *p) 2499{ 2500 return list_entry_rcu(p->thread_group.next, 2501 struct task_struct, thread_group); 2502} 2503 2504static inline int thread_group_empty(struct task_struct *p) 2505{ 2506 return list_empty(&p->thread_group); 2507} 2508 2509#define delay_group_leader(p) \ 2510 (thread_group_leader(p) && !thread_group_empty(p)) 2511 2512/* 2513 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2514 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2515 * pins the final release of task.io_context. Also protects ->cpuset and 2516 * ->cgroup.subsys[]. And ->vfork_done. 2517 * 2518 * Nests both inside and outside of read_lock(&tasklist_lock). 2519 * It must not be nested with write_lock_irq(&tasklist_lock), 2520 * neither inside nor outside. 2521 */ 2522static inline void task_lock(struct task_struct *p) 2523{ 2524 spin_lock(&p->alloc_lock); 2525} 2526 2527static inline void task_unlock(struct task_struct *p) 2528{ 2529 spin_unlock(&p->alloc_lock); 2530} 2531 2532extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2533 unsigned long *flags); 2534 2535static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2536 unsigned long *flags) 2537{ 2538 struct sighand_struct *ret; 2539 2540 ret = __lock_task_sighand(tsk, flags); 2541 (void)__cond_lock(&tsk->sighand->siglock, ret); 2542 return ret; 2543} 2544 2545static inline void unlock_task_sighand(struct task_struct *tsk, 2546 unsigned long *flags) 2547{ 2548 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2549} 2550 2551#ifdef CONFIG_CGROUPS 2552static inline void threadgroup_change_begin(struct task_struct *tsk) 2553{ 2554 down_read(&tsk->signal->group_rwsem); 2555} 2556static inline void threadgroup_change_end(struct task_struct *tsk) 2557{ 2558 up_read(&tsk->signal->group_rwsem); 2559} 2560 2561/** 2562 * threadgroup_lock - lock threadgroup 2563 * @tsk: member task of the threadgroup to lock 2564 * 2565 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter 2566 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or 2567 * change ->group_leader/pid. This is useful for cases where the threadgroup 2568 * needs to stay stable across blockable operations. 2569 * 2570 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for 2571 * synchronization. While held, no new task will be added to threadgroup 2572 * and no existing live task will have its PF_EXITING set. 2573 * 2574 * de_thread() does threadgroup_change_{begin|end}() when a non-leader 2575 * sub-thread becomes a new leader. 2576 */ 2577static inline void threadgroup_lock(struct task_struct *tsk) 2578{ 2579 down_write(&tsk->signal->group_rwsem); 2580} 2581 2582/** 2583 * threadgroup_unlock - unlock threadgroup 2584 * @tsk: member task of the threadgroup to unlock 2585 * 2586 * Reverse threadgroup_lock(). 2587 */ 2588static inline void threadgroup_unlock(struct task_struct *tsk) 2589{ 2590 up_write(&tsk->signal->group_rwsem); 2591} 2592#else 2593static inline void threadgroup_change_begin(struct task_struct *tsk) {} 2594static inline void threadgroup_change_end(struct task_struct *tsk) {} 2595static inline void threadgroup_lock(struct task_struct *tsk) {} 2596static inline void threadgroup_unlock(struct task_struct *tsk) {} 2597#endif 2598 2599#ifndef __HAVE_THREAD_FUNCTIONS 2600 2601#define task_thread_info(task) ((struct thread_info *)(task)->stack) 2602#define task_stack_page(task) ((task)->stack) 2603 2604static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2605{ 2606 *task_thread_info(p) = *task_thread_info(org); 2607 task_thread_info(p)->task = p; 2608} 2609 2610static inline unsigned long *end_of_stack(struct task_struct *p) 2611{ 2612 return (unsigned long *)(task_thread_info(p) + 1); 2613} 2614 2615#endif 2616 2617static inline int object_is_on_stack(void *obj) 2618{ 2619 void *stack = task_stack_page(current); 2620 2621 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2622} 2623 2624extern void thread_info_cache_init(void); 2625 2626#ifdef CONFIG_DEBUG_STACK_USAGE 2627static inline unsigned long stack_not_used(struct task_struct *p) 2628{ 2629 unsigned long *n = end_of_stack(p); 2630 2631 do { /* Skip over canary */ 2632 n++; 2633 } while (!*n); 2634 2635 return (unsigned long)n - (unsigned long)end_of_stack(p); 2636} 2637#endif 2638 2639/* set thread flags in other task's structures 2640 * - see asm/thread_info.h for TIF_xxxx flags available 2641 */ 2642static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2643{ 2644 set_ti_thread_flag(task_thread_info(tsk), flag); 2645} 2646 2647static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2648{ 2649 clear_ti_thread_flag(task_thread_info(tsk), flag); 2650} 2651 2652static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2653{ 2654 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2655} 2656 2657static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2658{ 2659 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2660} 2661 2662static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2663{ 2664 return test_ti_thread_flag(task_thread_info(tsk), flag); 2665} 2666 2667static inline void set_tsk_need_resched(struct task_struct *tsk) 2668{ 2669 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2670} 2671 2672static inline void clear_tsk_need_resched(struct task_struct *tsk) 2673{ 2674 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2675} 2676 2677static inline int test_tsk_need_resched(struct task_struct *tsk) 2678{ 2679 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2680} 2681 2682static inline int restart_syscall(void) 2683{ 2684 set_tsk_thread_flag(current, TIF_SIGPENDING); 2685 return -ERESTARTNOINTR; 2686} 2687 2688static inline int signal_pending(struct task_struct *p) 2689{ 2690 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2691} 2692 2693static inline int __fatal_signal_pending(struct task_struct *p) 2694{ 2695 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2696} 2697 2698static inline int fatal_signal_pending(struct task_struct *p) 2699{ 2700 return signal_pending(p) && __fatal_signal_pending(p); 2701} 2702 2703static inline int signal_pending_state(long state, struct task_struct *p) 2704{ 2705 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2706 return 0; 2707 if (!signal_pending(p)) 2708 return 0; 2709 2710 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2711} 2712 2713/* 2714 * cond_resched() and cond_resched_lock(): latency reduction via 2715 * explicit rescheduling in places that are safe. The return 2716 * value indicates whether a reschedule was done in fact. 2717 * cond_resched_lock() will drop the spinlock before scheduling, 2718 * cond_resched_softirq() will enable bhs before scheduling. 2719 */ 2720extern int _cond_resched(void); 2721 2722#define cond_resched() ({ \ 2723 __might_sleep(__FILE__, __LINE__, 0); \ 2724 _cond_resched(); \ 2725}) 2726 2727extern int __cond_resched_lock(spinlock_t *lock); 2728 2729#ifdef CONFIG_PREEMPT_COUNT 2730#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2731#else 2732#define PREEMPT_LOCK_OFFSET 0 2733#endif 2734 2735#define cond_resched_lock(lock) ({ \ 2736 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2737 __cond_resched_lock(lock); \ 2738}) 2739 2740extern int __cond_resched_softirq(void); 2741 2742#define cond_resched_softirq() ({ \ 2743 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2744 __cond_resched_softirq(); \ 2745}) 2746 2747static inline void cond_resched_rcu(void) 2748{ 2749#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 2750 rcu_read_unlock(); 2751 cond_resched(); 2752 rcu_read_lock(); 2753#endif 2754} 2755 2756/* 2757 * Does a critical section need to be broken due to another 2758 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2759 * but a general need for low latency) 2760 */ 2761static inline int spin_needbreak(spinlock_t *lock) 2762{ 2763#ifdef CONFIG_PREEMPT 2764 return spin_is_contended(lock); 2765#else 2766 return 0; 2767#endif 2768} 2769 2770/* 2771 * Idle thread specific functions to determine the need_resched 2772 * polling state. 2773 */ 2774#ifdef TIF_POLLING_NRFLAG 2775static inline int tsk_is_polling(struct task_struct *p) 2776{ 2777 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 2778} 2779 2780static inline void __current_set_polling(void) 2781{ 2782 set_thread_flag(TIF_POLLING_NRFLAG); 2783} 2784 2785static inline bool __must_check current_set_polling_and_test(void) 2786{ 2787 __current_set_polling(); 2788 2789 /* 2790 * Polling state must be visible before we test NEED_RESCHED, 2791 * paired by resched_task() 2792 */ 2793 smp_mb__after_atomic(); 2794 2795 return unlikely(tif_need_resched()); 2796} 2797 2798static inline void __current_clr_polling(void) 2799{ 2800 clear_thread_flag(TIF_POLLING_NRFLAG); 2801} 2802 2803static inline bool __must_check current_clr_polling_and_test(void) 2804{ 2805 __current_clr_polling(); 2806 2807 /* 2808 * Polling state must be visible before we test NEED_RESCHED, 2809 * paired by resched_task() 2810 */ 2811 smp_mb__after_atomic(); 2812 2813 return unlikely(tif_need_resched()); 2814} 2815 2816#else 2817static inline int tsk_is_polling(struct task_struct *p) { return 0; } 2818static inline void __current_set_polling(void) { } 2819static inline void __current_clr_polling(void) { } 2820 2821static inline bool __must_check current_set_polling_and_test(void) 2822{ 2823 return unlikely(tif_need_resched()); 2824} 2825static inline bool __must_check current_clr_polling_and_test(void) 2826{ 2827 return unlikely(tif_need_resched()); 2828} 2829#endif 2830 2831static inline void current_clr_polling(void) 2832{ 2833 __current_clr_polling(); 2834 2835 /* 2836 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit. 2837 * Once the bit is cleared, we'll get IPIs with every new 2838 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also 2839 * fold. 2840 */ 2841 smp_mb(); /* paired with resched_task() */ 2842 2843 preempt_fold_need_resched(); 2844} 2845 2846static __always_inline bool need_resched(void) 2847{ 2848 return unlikely(tif_need_resched()); 2849} 2850 2851/* 2852 * Thread group CPU time accounting. 2853 */ 2854void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 2855void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 2856 2857static inline void thread_group_cputime_init(struct signal_struct *sig) 2858{ 2859 raw_spin_lock_init(&sig->cputimer.lock); 2860} 2861 2862/* 2863 * Reevaluate whether the task has signals pending delivery. 2864 * Wake the task if so. 2865 * This is required every time the blocked sigset_t changes. 2866 * callers must hold sighand->siglock. 2867 */ 2868extern void recalc_sigpending_and_wake(struct task_struct *t); 2869extern void recalc_sigpending(void); 2870 2871extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 2872 2873static inline void signal_wake_up(struct task_struct *t, bool resume) 2874{ 2875 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 2876} 2877static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 2878{ 2879 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 2880} 2881 2882/* 2883 * Wrappers for p->thread_info->cpu access. No-op on UP. 2884 */ 2885#ifdef CONFIG_SMP 2886 2887static inline unsigned int task_cpu(const struct task_struct *p) 2888{ 2889 return task_thread_info(p)->cpu; 2890} 2891 2892static inline int task_node(const struct task_struct *p) 2893{ 2894 return cpu_to_node(task_cpu(p)); 2895} 2896 2897extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2898 2899#else 2900 2901static inline unsigned int task_cpu(const struct task_struct *p) 2902{ 2903 return 0; 2904} 2905 2906static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2907{ 2908} 2909 2910#endif /* CONFIG_SMP */ 2911 2912extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2913extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2914 2915#ifdef CONFIG_CGROUP_SCHED 2916extern struct task_group root_task_group; 2917#endif /* CONFIG_CGROUP_SCHED */ 2918 2919extern int task_can_switch_user(struct user_struct *up, 2920 struct task_struct *tsk); 2921 2922#ifdef CONFIG_TASK_XACCT 2923static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2924{ 2925 tsk->ioac.rchar += amt; 2926} 2927 2928static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2929{ 2930 tsk->ioac.wchar += amt; 2931} 2932 2933static inline void inc_syscr(struct task_struct *tsk) 2934{ 2935 tsk->ioac.syscr++; 2936} 2937 2938static inline void inc_syscw(struct task_struct *tsk) 2939{ 2940 tsk->ioac.syscw++; 2941} 2942#else 2943static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2944{ 2945} 2946 2947static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2948{ 2949} 2950 2951static inline void inc_syscr(struct task_struct *tsk) 2952{ 2953} 2954 2955static inline void inc_syscw(struct task_struct *tsk) 2956{ 2957} 2958#endif 2959 2960#ifndef TASK_SIZE_OF 2961#define TASK_SIZE_OF(tsk) TASK_SIZE 2962#endif 2963 2964#ifdef CONFIG_MEMCG 2965extern void mm_update_next_owner(struct mm_struct *mm); 2966extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); 2967#else 2968static inline void mm_update_next_owner(struct mm_struct *mm) 2969{ 2970} 2971 2972static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) 2973{ 2974} 2975#endif /* CONFIG_MEMCG */ 2976 2977static inline unsigned long task_rlimit(const struct task_struct *tsk, 2978 unsigned int limit) 2979{ 2980 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); 2981} 2982 2983static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 2984 unsigned int limit) 2985{ 2986 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); 2987} 2988 2989static inline unsigned long rlimit(unsigned int limit) 2990{ 2991 return task_rlimit(current, limit); 2992} 2993 2994static inline unsigned long rlimit_max(unsigned int limit) 2995{ 2996 return task_rlimit_max(current, limit); 2997} 2998 2999#endif