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