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.h> 29 30 #include <asm/page.h> 31 #include <asm/ptrace.h> 32 #include <linux/cputime.h> 33 34 #include <linux/smp.h> 35 #include <linux/sem.h> 36 #include <linux/shm.h> 37 #include <linux/signal.h> 38 #include <linux/compiler.h> 39 #include <linux/completion.h> 40 #include <linux/pid.h> 41 #include <linux/percpu.h> 42 #include <linux/topology.h> 43 #include <linux/proportions.h> 44 #include <linux/seccomp.h> 45 #include <linux/rcupdate.h> 46 #include <linux/rculist.h> 47 #include <linux/rtmutex.h> 48 49 #include <linux/time.h> 50 #include <linux/param.h> 51 #include <linux/resource.h> 52 #include <linux/timer.h> 53 #include <linux/hrtimer.h> 54 #include <linux/task_io_accounting.h> 55 #include <linux/latencytop.h> 56 #include <linux/cred.h> 57 #include <linux/llist.h> 58 #include <linux/uidgid.h> 59 #include <linux/gfp.h> 60 #include <linux/magic.h> 61 #include <linux/cgroup-defs.h> 62 63 #include <asm/processor.h> 64 65 #define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */ 66 67 /* 68 * Extended scheduling parameters data structure. 69 * 70 * This is needed because the original struct sched_param can not be 71 * altered without introducing ABI issues with legacy applications 72 * (e.g., in sched_getparam()). 73 * 74 * However, the possibility of specifying more than just a priority for 75 * the tasks may be useful for a wide variety of application fields, e.g., 76 * multimedia, streaming, automation and control, and many others. 77 * 78 * This variant (sched_attr) is meant at describing a so-called 79 * sporadic time-constrained task. In such model a task is specified by: 80 * - the activation period or minimum instance inter-arrival time; 81 * - the maximum (or average, depending on the actual scheduling 82 * discipline) computation time of all instances, a.k.a. runtime; 83 * - the deadline (relative to the actual activation time) of each 84 * instance. 85 * Very briefly, a periodic (sporadic) task asks for the execution of 86 * some specific computation --which is typically called an instance-- 87 * (at most) every period. Moreover, each instance typically lasts no more 88 * than the runtime and must be completed by time instant t equal to 89 * the instance activation time + the deadline. 90 * 91 * This is reflected by the actual fields of the sched_attr structure: 92 * 93 * @size size of the structure, for fwd/bwd compat. 94 * 95 * @sched_policy task's scheduling policy 96 * @sched_flags for customizing the scheduler behaviour 97 * @sched_nice task's nice value (SCHED_NORMAL/BATCH) 98 * @sched_priority task's static priority (SCHED_FIFO/RR) 99 * @sched_deadline representative of the task's deadline 100 * @sched_runtime representative of the task's runtime 101 * @sched_period representative of the task's period 102 * 103 * Given this task model, there are a multiplicity of scheduling algorithms 104 * and policies, that can be used to ensure all the tasks will make their 105 * timing constraints. 106 * 107 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the 108 * only user of this new interface. More information about the algorithm 109 * available in the scheduling class file or in Documentation/. 110 */ 111 struct sched_attr { 112 u32 size; 113 114 u32 sched_policy; 115 u64 sched_flags; 116 117 /* SCHED_NORMAL, SCHED_BATCH */ 118 s32 sched_nice; 119 120 /* SCHED_FIFO, SCHED_RR */ 121 u32 sched_priority; 122 123 /* SCHED_DEADLINE */ 124 u64 sched_runtime; 125 u64 sched_deadline; 126 u64 sched_period; 127 }; 128 129 struct futex_pi_state; 130 struct robust_list_head; 131 struct bio_list; 132 struct fs_struct; 133 struct perf_event_context; 134 struct blk_plug; 135 struct filename; 136 struct nameidata; 137 138 #define VMACACHE_BITS 2 139 #define VMACACHE_SIZE (1U << VMACACHE_BITS) 140 #define VMACACHE_MASK (VMACACHE_SIZE - 1) 141 142 /* 143 * These are the constant used to fake the fixed-point load-average 144 * counting. Some notes: 145 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 146 * a load-average precision of 10 bits integer + 11 bits fractional 147 * - if you want to count load-averages more often, you need more 148 * precision, or rounding will get you. With 2-second counting freq, 149 * the EXP_n values would be 1981, 2034 and 2043 if still using only 150 * 11 bit fractions. 151 */ 152 extern unsigned long avenrun[]; /* Load averages */ 153 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 154 155 #define FSHIFT 11 /* nr of bits of precision */ 156 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 157 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 158 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 159 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 160 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 161 162 #define CALC_LOAD(load,exp,n) \ 163 load *= exp; \ 164 load += n*(FIXED_1-exp); \ 165 load >>= FSHIFT; 166 167 extern unsigned long total_forks; 168 extern int nr_threads; 169 DECLARE_PER_CPU(unsigned long, process_counts); 170 extern int nr_processes(void); 171 extern unsigned long nr_running(void); 172 extern bool single_task_running(void); 173 extern unsigned long nr_iowait(void); 174 extern unsigned long nr_iowait_cpu(int cpu); 175 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load); 176 177 extern void calc_global_load(unsigned long ticks); 178 179 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 180 extern void update_cpu_load_nohz(void); 181 #else 182 static inline void update_cpu_load_nohz(void) { } 183 #endif 184 185 extern unsigned long get_parent_ip(unsigned long addr); 186 187 extern void dump_cpu_task(int cpu); 188 189 struct seq_file; 190 struct cfs_rq; 191 struct task_group; 192 #ifdef CONFIG_SCHED_DEBUG 193 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 194 extern void proc_sched_set_task(struct task_struct *p); 195 #endif 196 197 /* 198 * Task state bitmask. NOTE! These bits are also 199 * encoded in fs/proc/array.c: get_task_state(). 200 * 201 * We have two separate sets of flags: task->state 202 * is about runnability, while task->exit_state are 203 * about the task exiting. Confusing, but this way 204 * modifying one set can't modify the other one by 205 * mistake. 206 */ 207 #define TASK_RUNNING 0 208 #define TASK_INTERRUPTIBLE 1 209 #define TASK_UNINTERRUPTIBLE 2 210 #define __TASK_STOPPED 4 211 #define __TASK_TRACED 8 212 /* in tsk->exit_state */ 213 #define EXIT_DEAD 16 214 #define EXIT_ZOMBIE 32 215 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 216 /* in tsk->state again */ 217 #define TASK_DEAD 64 218 #define TASK_WAKEKILL 128 219 #define TASK_WAKING 256 220 #define TASK_PARKED 512 221 #define TASK_NOLOAD 1024 222 #define TASK_STATE_MAX 2048 223 224 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN" 225 226 extern char ___assert_task_state[1 - 2*!!( 227 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 228 229 /* Convenience macros for the sake of set_task_state */ 230 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 231 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 232 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 233 234 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 235 236 /* Convenience macros for the sake of wake_up */ 237 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 238 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 239 240 /* get_task_state() */ 241 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 242 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 243 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD) 244 245 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 246 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 247 #define task_is_stopped_or_traced(task) \ 248 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 249 #define task_contributes_to_load(task) \ 250 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 251 (task->flags & PF_FROZEN) == 0 && \ 252 (task->state & TASK_NOLOAD) == 0) 253 254 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 255 256 #define __set_task_state(tsk, state_value) \ 257 do { \ 258 (tsk)->task_state_change = _THIS_IP_; \ 259 (tsk)->state = (state_value); \ 260 } while (0) 261 #define set_task_state(tsk, state_value) \ 262 do { \ 263 (tsk)->task_state_change = _THIS_IP_; \ 264 smp_store_mb((tsk)->state, (state_value)); \ 265 } while (0) 266 267 /* 268 * set_current_state() includes a barrier so that the write of current->state 269 * is correctly serialised wrt the caller's subsequent test of whether to 270 * actually sleep: 271 * 272 * set_current_state(TASK_UNINTERRUPTIBLE); 273 * if (do_i_need_to_sleep()) 274 * schedule(); 275 * 276 * If the caller does not need such serialisation then use __set_current_state() 277 */ 278 #define __set_current_state(state_value) \ 279 do { \ 280 current->task_state_change = _THIS_IP_; \ 281 current->state = (state_value); \ 282 } while (0) 283 #define set_current_state(state_value) \ 284 do { \ 285 current->task_state_change = _THIS_IP_; \ 286 smp_store_mb(current->state, (state_value)); \ 287 } while (0) 288 289 #else 290 291 #define __set_task_state(tsk, state_value) \ 292 do { (tsk)->state = (state_value); } while (0) 293 #define set_task_state(tsk, state_value) \ 294 smp_store_mb((tsk)->state, (state_value)) 295 296 /* 297 * set_current_state() includes a barrier so that the write of current->state 298 * is correctly serialised wrt the caller's subsequent test of whether to 299 * actually sleep: 300 * 301 * set_current_state(TASK_UNINTERRUPTIBLE); 302 * if (do_i_need_to_sleep()) 303 * schedule(); 304 * 305 * If the caller does not need such serialisation then use __set_current_state() 306 */ 307 #define __set_current_state(state_value) \ 308 do { current->state = (state_value); } while (0) 309 #define set_current_state(state_value) \ 310 smp_store_mb(current->state, (state_value)) 311 312 #endif 313 314 /* Task command name length */ 315 #define TASK_COMM_LEN 16 316 317 #include <linux/spinlock.h> 318 319 /* 320 * This serializes "schedule()" and also protects 321 * the run-queue from deletions/modifications (but 322 * _adding_ to the beginning of the run-queue has 323 * a separate lock). 324 */ 325 extern rwlock_t tasklist_lock; 326 extern spinlock_t mmlist_lock; 327 328 struct task_struct; 329 330 #ifdef CONFIG_PROVE_RCU 331 extern int lockdep_tasklist_lock_is_held(void); 332 #endif /* #ifdef CONFIG_PROVE_RCU */ 333 334 extern void sched_init(void); 335 extern void sched_init_smp(void); 336 extern asmlinkage void schedule_tail(struct task_struct *prev); 337 extern void init_idle(struct task_struct *idle, int cpu); 338 extern void init_idle_bootup_task(struct task_struct *idle); 339 340 extern cpumask_var_t cpu_isolated_map; 341 342 extern int runqueue_is_locked(int cpu); 343 344 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 345 extern void nohz_balance_enter_idle(int cpu); 346 extern void set_cpu_sd_state_idle(void); 347 extern int get_nohz_timer_target(void); 348 #else 349 static inline void nohz_balance_enter_idle(int cpu) { } 350 static inline void set_cpu_sd_state_idle(void) { } 351 #endif 352 353 /* 354 * Only dump TASK_* tasks. (0 for all tasks) 355 */ 356 extern void show_state_filter(unsigned long state_filter); 357 358 static inline void show_state(void) 359 { 360 show_state_filter(0); 361 } 362 363 extern void show_regs(struct pt_regs *); 364 365 /* 366 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 367 * task), SP is the stack pointer of the first frame that should be shown in the back 368 * trace (or NULL if the entire call-chain of the task should be shown). 369 */ 370 extern void show_stack(struct task_struct *task, unsigned long *sp); 371 372 extern void cpu_init (void); 373 extern void trap_init(void); 374 extern void update_process_times(int user); 375 extern void scheduler_tick(void); 376 377 extern void sched_show_task(struct task_struct *p); 378 379 #ifdef CONFIG_LOCKUP_DETECTOR 380 extern void touch_softlockup_watchdog(void); 381 extern void touch_softlockup_watchdog_sync(void); 382 extern void touch_all_softlockup_watchdogs(void); 383 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 384 void __user *buffer, 385 size_t *lenp, loff_t *ppos); 386 extern unsigned int softlockup_panic; 387 void lockup_detector_init(void); 388 #else 389 static inline void touch_softlockup_watchdog(void) 390 { 391 } 392 static inline void touch_softlockup_watchdog_sync(void) 393 { 394 } 395 static inline void touch_all_softlockup_watchdogs(void) 396 { 397 } 398 static inline void lockup_detector_init(void) 399 { 400 } 401 #endif 402 403 #ifdef CONFIG_DETECT_HUNG_TASK 404 void reset_hung_task_detector(void); 405 #else 406 static inline void reset_hung_task_detector(void) 407 { 408 } 409 #endif 410 411 /* Attach to any functions which should be ignored in wchan output. */ 412 #define __sched __attribute__((__section__(".sched.text"))) 413 414 /* Linker adds these: start and end of __sched functions */ 415 extern char __sched_text_start[], __sched_text_end[]; 416 417 /* Is this address in the __sched functions? */ 418 extern int in_sched_functions(unsigned long addr); 419 420 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 421 extern signed long schedule_timeout(signed long timeout); 422 extern signed long schedule_timeout_interruptible(signed long timeout); 423 extern signed long schedule_timeout_killable(signed long timeout); 424 extern signed long schedule_timeout_uninterruptible(signed long timeout); 425 asmlinkage void schedule(void); 426 extern void schedule_preempt_disabled(void); 427 428 extern long io_schedule_timeout(long timeout); 429 430 static inline void io_schedule(void) 431 { 432 io_schedule_timeout(MAX_SCHEDULE_TIMEOUT); 433 } 434 435 struct nsproxy; 436 struct user_namespace; 437 438 #ifdef CONFIG_MMU 439 extern void arch_pick_mmap_layout(struct mm_struct *mm); 440 extern unsigned long 441 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 442 unsigned long, unsigned long); 443 extern unsigned long 444 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 445 unsigned long len, unsigned long pgoff, 446 unsigned long flags); 447 #else 448 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 449 #endif 450 451 #define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 452 #define SUID_DUMP_USER 1 /* Dump as user of process */ 453 #define SUID_DUMP_ROOT 2 /* Dump as root */ 454 455 /* mm flags */ 456 457 /* for SUID_DUMP_* above */ 458 #define MMF_DUMPABLE_BITS 2 459 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 460 461 extern void set_dumpable(struct mm_struct *mm, int value); 462 /* 463 * This returns the actual value of the suid_dumpable flag. For things 464 * that are using this for checking for privilege transitions, it must 465 * test against SUID_DUMP_USER rather than treating it as a boolean 466 * value. 467 */ 468 static inline int __get_dumpable(unsigned long mm_flags) 469 { 470 return mm_flags & MMF_DUMPABLE_MASK; 471 } 472 473 static inline int get_dumpable(struct mm_struct *mm) 474 { 475 return __get_dumpable(mm->flags); 476 } 477 478 /* coredump filter bits */ 479 #define MMF_DUMP_ANON_PRIVATE 2 480 #define MMF_DUMP_ANON_SHARED 3 481 #define MMF_DUMP_MAPPED_PRIVATE 4 482 #define MMF_DUMP_MAPPED_SHARED 5 483 #define MMF_DUMP_ELF_HEADERS 6 484 #define MMF_DUMP_HUGETLB_PRIVATE 7 485 #define MMF_DUMP_HUGETLB_SHARED 8 486 487 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 488 #define MMF_DUMP_FILTER_BITS 7 489 #define MMF_DUMP_FILTER_MASK \ 490 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 491 #define MMF_DUMP_FILTER_DEFAULT \ 492 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 493 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 494 495 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 496 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 497 #else 498 # define MMF_DUMP_MASK_DEFAULT_ELF 0 499 #endif 500 /* leave room for more dump flags */ 501 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 502 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 503 #define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 504 505 #define MMF_HAS_UPROBES 19 /* has uprobes */ 506 #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 507 508 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 509 510 struct sighand_struct { 511 atomic_t count; 512 struct k_sigaction action[_NSIG]; 513 spinlock_t siglock; 514 wait_queue_head_t signalfd_wqh; 515 }; 516 517 struct pacct_struct { 518 int ac_flag; 519 long ac_exitcode; 520 unsigned long ac_mem; 521 cputime_t ac_utime, ac_stime; 522 unsigned long ac_minflt, ac_majflt; 523 }; 524 525 struct cpu_itimer { 526 cputime_t expires; 527 cputime_t incr; 528 u32 error; 529 u32 incr_error; 530 }; 531 532 /** 533 * struct cputime - snaphsot of system and user cputime 534 * @utime: time spent in user mode 535 * @stime: time spent in system mode 536 * 537 * Gathers a generic snapshot of user and system time. 538 */ 539 struct cputime { 540 cputime_t utime; 541 cputime_t stime; 542 }; 543 544 /** 545 * struct task_cputime - collected CPU time counts 546 * @utime: time spent in user mode, in &cputime_t units 547 * @stime: time spent in kernel mode, in &cputime_t units 548 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 549 * 550 * This is an extension of struct cputime that includes the total runtime 551 * spent by the task from the scheduler point of view. 552 * 553 * As a result, this structure groups together three kinds of CPU time 554 * that are tracked for threads and thread groups. Most things considering 555 * CPU time want to group these counts together and treat all three 556 * of them in parallel. 557 */ 558 struct task_cputime { 559 cputime_t utime; 560 cputime_t stime; 561 unsigned long long sum_exec_runtime; 562 }; 563 /* Alternate field names when used to cache expirations. */ 564 #define prof_exp stime 565 #define virt_exp utime 566 #define sched_exp sum_exec_runtime 567 568 #define INIT_CPUTIME \ 569 (struct task_cputime) { \ 570 .utime = 0, \ 571 .stime = 0, \ 572 .sum_exec_runtime = 0, \ 573 } 574 575 /* 576 * This is the atomic variant of task_cputime, which can be used for 577 * storing and updating task_cputime statistics without locking. 578 */ 579 struct task_cputime_atomic { 580 atomic64_t utime; 581 atomic64_t stime; 582 atomic64_t sum_exec_runtime; 583 }; 584 585 #define INIT_CPUTIME_ATOMIC \ 586 (struct task_cputime_atomic) { \ 587 .utime = ATOMIC64_INIT(0), \ 588 .stime = ATOMIC64_INIT(0), \ 589 .sum_exec_runtime = ATOMIC64_INIT(0), \ 590 } 591 592 #ifdef CONFIG_PREEMPT_COUNT 593 #define PREEMPT_DISABLED (1 + PREEMPT_ENABLED) 594 #else 595 #define PREEMPT_DISABLED PREEMPT_ENABLED 596 #endif 597 598 /* 599 * Disable preemption until the scheduler is running. 600 * Reset by start_kernel()->sched_init()->init_idle(). 601 * 602 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 603 * before the scheduler is active -- see should_resched(). 604 */ 605 #define INIT_PREEMPT_COUNT (PREEMPT_DISABLED + PREEMPT_ACTIVE) 606 607 /** 608 * struct thread_group_cputimer - thread group interval timer counts 609 * @cputime_atomic: atomic thread group interval timers. 610 * @running: non-zero when there are timers running and 611 * @cputime receives updates. 612 * 613 * This structure contains the version of task_cputime, above, that is 614 * used for thread group CPU timer calculations. 615 */ 616 struct thread_group_cputimer { 617 struct task_cputime_atomic cputime_atomic; 618 int running; 619 }; 620 621 #include <linux/rwsem.h> 622 struct autogroup; 623 624 /* 625 * NOTE! "signal_struct" does not have its own 626 * locking, because a shared signal_struct always 627 * implies a shared sighand_struct, so locking 628 * sighand_struct is always a proper superset of 629 * the locking of signal_struct. 630 */ 631 struct signal_struct { 632 atomic_t sigcnt; 633 atomic_t live; 634 int nr_threads; 635 struct list_head thread_head; 636 637 wait_queue_head_t wait_chldexit; /* for wait4() */ 638 639 /* current thread group signal load-balancing target: */ 640 struct task_struct *curr_target; 641 642 /* shared signal handling: */ 643 struct sigpending shared_pending; 644 645 /* thread group exit support */ 646 int group_exit_code; 647 /* overloaded: 648 * - notify group_exit_task when ->count is equal to notify_count 649 * - everyone except group_exit_task is stopped during signal delivery 650 * of fatal signals, group_exit_task processes the signal. 651 */ 652 int notify_count; 653 struct task_struct *group_exit_task; 654 655 /* thread group stop support, overloads group_exit_code too */ 656 int group_stop_count; 657 unsigned int flags; /* see SIGNAL_* flags below */ 658 659 /* 660 * PR_SET_CHILD_SUBREAPER marks a process, like a service 661 * manager, to re-parent orphan (double-forking) child processes 662 * to this process instead of 'init'. The service manager is 663 * able to receive SIGCHLD signals and is able to investigate 664 * the process until it calls wait(). All children of this 665 * process will inherit a flag if they should look for a 666 * child_subreaper process at exit. 667 */ 668 unsigned int is_child_subreaper:1; 669 unsigned int has_child_subreaper:1; 670 671 /* POSIX.1b Interval Timers */ 672 int posix_timer_id; 673 struct list_head posix_timers; 674 675 /* ITIMER_REAL timer for the process */ 676 struct hrtimer real_timer; 677 struct pid *leader_pid; 678 ktime_t it_real_incr; 679 680 /* 681 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 682 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 683 * values are defined to 0 and 1 respectively 684 */ 685 struct cpu_itimer it[2]; 686 687 /* 688 * Thread group totals for process CPU timers. 689 * See thread_group_cputimer(), et al, for details. 690 */ 691 struct thread_group_cputimer cputimer; 692 693 /* Earliest-expiration cache. */ 694 struct task_cputime cputime_expires; 695 696 struct list_head cpu_timers[3]; 697 698 struct pid *tty_old_pgrp; 699 700 /* boolean value for session group leader */ 701 int leader; 702 703 struct tty_struct *tty; /* NULL if no tty */ 704 705 #ifdef CONFIG_SCHED_AUTOGROUP 706 struct autogroup *autogroup; 707 #endif 708 /* 709 * Cumulative resource counters for dead threads in the group, 710 * and for reaped dead child processes forked by this group. 711 * Live threads maintain their own counters and add to these 712 * in __exit_signal, except for the group leader. 713 */ 714 seqlock_t stats_lock; 715 cputime_t utime, stime, cutime, cstime; 716 cputime_t gtime; 717 cputime_t cgtime; 718 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 719 struct cputime prev_cputime; 720 #endif 721 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 722 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 723 unsigned long inblock, oublock, cinblock, coublock; 724 unsigned long maxrss, cmaxrss; 725 struct task_io_accounting ioac; 726 727 /* 728 * Cumulative ns of schedule CPU time fo dead threads in the 729 * group, not including a zombie group leader, (This only differs 730 * from jiffies_to_ns(utime + stime) if sched_clock uses something 731 * other than jiffies.) 732 */ 733 unsigned long long sum_sched_runtime; 734 735 /* 736 * We don't bother to synchronize most readers of this at all, 737 * because there is no reader checking a limit that actually needs 738 * to get both rlim_cur and rlim_max atomically, and either one 739 * alone is a single word that can safely be read normally. 740 * getrlimit/setrlimit use task_lock(current->group_leader) to 741 * protect this instead of the siglock, because they really 742 * have no need to disable irqs. 743 */ 744 struct rlimit rlim[RLIM_NLIMITS]; 745 746 #ifdef CONFIG_BSD_PROCESS_ACCT 747 struct pacct_struct pacct; /* per-process accounting information */ 748 #endif 749 #ifdef CONFIG_TASKSTATS 750 struct taskstats *stats; 751 #endif 752 #ifdef CONFIG_AUDIT 753 unsigned audit_tty; 754 unsigned audit_tty_log_passwd; 755 struct tty_audit_buf *tty_audit_buf; 756 #endif 757 758 oom_flags_t oom_flags; 759 short oom_score_adj; /* OOM kill score adjustment */ 760 short oom_score_adj_min; /* OOM kill score adjustment min value. 761 * Only settable by CAP_SYS_RESOURCE. */ 762 763 struct mutex cred_guard_mutex; /* guard against foreign influences on 764 * credential calculations 765 * (notably. ptrace) */ 766 }; 767 768 /* 769 * Bits in flags field of signal_struct. 770 */ 771 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 772 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 773 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 774 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 775 /* 776 * Pending notifications to parent. 777 */ 778 #define SIGNAL_CLD_STOPPED 0x00000010 779 #define SIGNAL_CLD_CONTINUED 0x00000020 780 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 781 782 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 783 784 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 785 static inline int signal_group_exit(const struct signal_struct *sig) 786 { 787 return (sig->flags & SIGNAL_GROUP_EXIT) || 788 (sig->group_exit_task != NULL); 789 } 790 791 /* 792 * Some day this will be a full-fledged user tracking system.. 793 */ 794 struct user_struct { 795 atomic_t __count; /* reference count */ 796 atomic_t processes; /* How many processes does this user have? */ 797 atomic_t sigpending; /* How many pending signals does this user have? */ 798 #ifdef CONFIG_INOTIFY_USER 799 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 800 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 801 #endif 802 #ifdef CONFIG_FANOTIFY 803 atomic_t fanotify_listeners; 804 #endif 805 #ifdef CONFIG_EPOLL 806 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 807 #endif 808 #ifdef CONFIG_POSIX_MQUEUE 809 /* protected by mq_lock */ 810 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 811 #endif 812 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 813 814 #ifdef CONFIG_KEYS 815 struct key *uid_keyring; /* UID specific keyring */ 816 struct key *session_keyring; /* UID's default session keyring */ 817 #endif 818 819 /* Hash table maintenance information */ 820 struct hlist_node uidhash_node; 821 kuid_t uid; 822 823 #ifdef CONFIG_PERF_EVENTS 824 atomic_long_t locked_vm; 825 #endif 826 }; 827 828 extern int uids_sysfs_init(void); 829 830 extern struct user_struct *find_user(kuid_t); 831 832 extern struct user_struct root_user; 833 #define INIT_USER (&root_user) 834 835 836 struct backing_dev_info; 837 struct reclaim_state; 838 839 #ifdef CONFIG_SCHED_INFO 840 struct sched_info { 841 /* cumulative counters */ 842 unsigned long pcount; /* # of times run on this cpu */ 843 unsigned long long run_delay; /* time spent waiting on a runqueue */ 844 845 /* timestamps */ 846 unsigned long long last_arrival,/* when we last ran on a cpu */ 847 last_queued; /* when we were last queued to run */ 848 }; 849 #endif /* CONFIG_SCHED_INFO */ 850 851 #ifdef CONFIG_TASK_DELAY_ACCT 852 struct task_delay_info { 853 spinlock_t lock; 854 unsigned int flags; /* Private per-task flags */ 855 856 /* For each stat XXX, add following, aligned appropriately 857 * 858 * struct timespec XXX_start, XXX_end; 859 * u64 XXX_delay; 860 * u32 XXX_count; 861 * 862 * Atomicity of updates to XXX_delay, XXX_count protected by 863 * single lock above (split into XXX_lock if contention is an issue). 864 */ 865 866 /* 867 * XXX_count is incremented on every XXX operation, the delay 868 * associated with the operation is added to XXX_delay. 869 * XXX_delay contains the accumulated delay time in nanoseconds. 870 */ 871 u64 blkio_start; /* Shared by blkio, swapin */ 872 u64 blkio_delay; /* wait for sync block io completion */ 873 u64 swapin_delay; /* wait for swapin block io completion */ 874 u32 blkio_count; /* total count of the number of sync block */ 875 /* io operations performed */ 876 u32 swapin_count; /* total count of the number of swapin block */ 877 /* io operations performed */ 878 879 u64 freepages_start; 880 u64 freepages_delay; /* wait for memory reclaim */ 881 u32 freepages_count; /* total count of memory reclaim */ 882 }; 883 #endif /* CONFIG_TASK_DELAY_ACCT */ 884 885 static inline int sched_info_on(void) 886 { 887 #ifdef CONFIG_SCHEDSTATS 888 return 1; 889 #elif defined(CONFIG_TASK_DELAY_ACCT) 890 extern int delayacct_on; 891 return delayacct_on; 892 #else 893 return 0; 894 #endif 895 } 896 897 enum cpu_idle_type { 898 CPU_IDLE, 899 CPU_NOT_IDLE, 900 CPU_NEWLY_IDLE, 901 CPU_MAX_IDLE_TYPES 902 }; 903 904 /* 905 * Increase resolution of cpu_capacity calculations 906 */ 907 #define SCHED_CAPACITY_SHIFT 10 908 #define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 909 910 /* 911 * Wake-queues are lists of tasks with a pending wakeup, whose 912 * callers have already marked the task as woken internally, 913 * and can thus carry on. A common use case is being able to 914 * do the wakeups once the corresponding user lock as been 915 * released. 916 * 917 * We hold reference to each task in the list across the wakeup, 918 * thus guaranteeing that the memory is still valid by the time 919 * the actual wakeups are performed in wake_up_q(). 920 * 921 * One per task suffices, because there's never a need for a task to be 922 * in two wake queues simultaneously; it is forbidden to abandon a task 923 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is 924 * already in a wake queue, the wakeup will happen soon and the second 925 * waker can just skip it. 926 * 927 * The WAKE_Q macro declares and initializes the list head. 928 * wake_up_q() does NOT reinitialize the list; it's expected to be 929 * called near the end of a function, where the fact that the queue is 930 * not used again will be easy to see by inspection. 931 * 932 * Note that this can cause spurious wakeups. schedule() callers 933 * must ensure the call is done inside a loop, confirming that the 934 * wakeup condition has in fact occurred. 935 */ 936 struct wake_q_node { 937 struct wake_q_node *next; 938 }; 939 940 struct wake_q_head { 941 struct wake_q_node *first; 942 struct wake_q_node **lastp; 943 }; 944 945 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01) 946 947 #define WAKE_Q(name) \ 948 struct wake_q_head name = { WAKE_Q_TAIL, &name.first } 949 950 extern void wake_q_add(struct wake_q_head *head, 951 struct task_struct *task); 952 extern void wake_up_q(struct wake_q_head *head); 953 954 /* 955 * sched-domains (multiprocessor balancing) declarations: 956 */ 957 #ifdef CONFIG_SMP 958 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 959 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 960 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 961 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 962 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 963 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 964 #define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu power */ 965 #define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ 966 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 967 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 968 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 969 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 970 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 971 #define SD_NUMA 0x4000 /* cross-node balancing */ 972 973 #ifdef CONFIG_SCHED_SMT 974 static inline int cpu_smt_flags(void) 975 { 976 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; 977 } 978 #endif 979 980 #ifdef CONFIG_SCHED_MC 981 static inline int cpu_core_flags(void) 982 { 983 return SD_SHARE_PKG_RESOURCES; 984 } 985 #endif 986 987 #ifdef CONFIG_NUMA 988 static inline int cpu_numa_flags(void) 989 { 990 return SD_NUMA; 991 } 992 #endif 993 994 struct sched_domain_attr { 995 int relax_domain_level; 996 }; 997 998 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 999 .relax_domain_level = -1, \ 1000 } 1001 1002 extern int sched_domain_level_max; 1003 1004 struct sched_group; 1005 1006 struct sched_domain { 1007 /* These fields must be setup */ 1008 struct sched_domain *parent; /* top domain must be null terminated */ 1009 struct sched_domain *child; /* bottom domain must be null terminated */ 1010 struct sched_group *groups; /* the balancing groups of the domain */ 1011 unsigned long min_interval; /* Minimum balance interval ms */ 1012 unsigned long max_interval; /* Maximum balance interval ms */ 1013 unsigned int busy_factor; /* less balancing by factor if busy */ 1014 unsigned int imbalance_pct; /* No balance until over watermark */ 1015 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 1016 unsigned int busy_idx; 1017 unsigned int idle_idx; 1018 unsigned int newidle_idx; 1019 unsigned int wake_idx; 1020 unsigned int forkexec_idx; 1021 unsigned int smt_gain; 1022 1023 int nohz_idle; /* NOHZ IDLE status */ 1024 int flags; /* See SD_* */ 1025 int level; 1026 1027 /* Runtime fields. */ 1028 unsigned long last_balance; /* init to jiffies. units in jiffies */ 1029 unsigned int balance_interval; /* initialise to 1. units in ms. */ 1030 unsigned int nr_balance_failed; /* initialise to 0 */ 1031 1032 /* idle_balance() stats */ 1033 u64 max_newidle_lb_cost; 1034 unsigned long next_decay_max_lb_cost; 1035 1036 #ifdef CONFIG_SCHEDSTATS 1037 /* load_balance() stats */ 1038 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 1039 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 1040 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 1041 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 1042 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 1043 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 1044 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 1045 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 1046 1047 /* Active load balancing */ 1048 unsigned int alb_count; 1049 unsigned int alb_failed; 1050 unsigned int alb_pushed; 1051 1052 /* SD_BALANCE_EXEC stats */ 1053 unsigned int sbe_count; 1054 unsigned int sbe_balanced; 1055 unsigned int sbe_pushed; 1056 1057 /* SD_BALANCE_FORK stats */ 1058 unsigned int sbf_count; 1059 unsigned int sbf_balanced; 1060 unsigned int sbf_pushed; 1061 1062 /* try_to_wake_up() stats */ 1063 unsigned int ttwu_wake_remote; 1064 unsigned int ttwu_move_affine; 1065 unsigned int ttwu_move_balance; 1066 #endif 1067 #ifdef CONFIG_SCHED_DEBUG 1068 char *name; 1069 #endif 1070 union { 1071 void *private; /* used during construction */ 1072 struct rcu_head rcu; /* used during destruction */ 1073 }; 1074 1075 unsigned int span_weight; 1076 /* 1077 * Span of all CPUs in this domain. 1078 * 1079 * NOTE: this field is variable length. (Allocated dynamically 1080 * by attaching extra space to the end of the structure, 1081 * depending on how many CPUs the kernel has booted up with) 1082 */ 1083 unsigned long span[0]; 1084 }; 1085 1086 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 1087 { 1088 return to_cpumask(sd->span); 1089 } 1090 1091 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1092 struct sched_domain_attr *dattr_new); 1093 1094 /* Allocate an array of sched domains, for partition_sched_domains(). */ 1095 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 1096 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 1097 1098 bool cpus_share_cache(int this_cpu, int that_cpu); 1099 1100 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); 1101 typedef int (*sched_domain_flags_f)(void); 1102 1103 #define SDTL_OVERLAP 0x01 1104 1105 struct sd_data { 1106 struct sched_domain **__percpu sd; 1107 struct sched_group **__percpu sg; 1108 struct sched_group_capacity **__percpu sgc; 1109 }; 1110 1111 struct sched_domain_topology_level { 1112 sched_domain_mask_f mask; 1113 sched_domain_flags_f sd_flags; 1114 int flags; 1115 int numa_level; 1116 struct sd_data data; 1117 #ifdef CONFIG_SCHED_DEBUG 1118 char *name; 1119 #endif 1120 }; 1121 1122 extern struct sched_domain_topology_level *sched_domain_topology; 1123 1124 extern void set_sched_topology(struct sched_domain_topology_level *tl); 1125 extern void wake_up_if_idle(int cpu); 1126 1127 #ifdef CONFIG_SCHED_DEBUG 1128 # define SD_INIT_NAME(type) .name = #type 1129 #else 1130 # define SD_INIT_NAME(type) 1131 #endif 1132 1133 #else /* CONFIG_SMP */ 1134 1135 struct sched_domain_attr; 1136 1137 static inline void 1138 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1139 struct sched_domain_attr *dattr_new) 1140 { 1141 } 1142 1143 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1144 { 1145 return true; 1146 } 1147 1148 #endif /* !CONFIG_SMP */ 1149 1150 1151 struct io_context; /* See blkdev.h */ 1152 1153 1154 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1155 extern void prefetch_stack(struct task_struct *t); 1156 #else 1157 static inline void prefetch_stack(struct task_struct *t) { } 1158 #endif 1159 1160 struct audit_context; /* See audit.c */ 1161 struct mempolicy; 1162 struct pipe_inode_info; 1163 struct uts_namespace; 1164 1165 struct load_weight { 1166 unsigned long weight; 1167 u32 inv_weight; 1168 }; 1169 1170 struct sched_avg { 1171 u64 last_runnable_update; 1172 s64 decay_count; 1173 /* 1174 * utilization_avg_contrib describes the amount of time that a 1175 * sched_entity is running on a CPU. It is based on running_avg_sum 1176 * and is scaled in the range [0..SCHED_LOAD_SCALE]. 1177 * load_avg_contrib described the amount of time that a sched_entity 1178 * is runnable on a rq. It is based on both runnable_avg_sum and the 1179 * weight of the task. 1180 */ 1181 unsigned long load_avg_contrib, utilization_avg_contrib; 1182 /* 1183 * These sums represent an infinite geometric series and so are bound 1184 * above by 1024/(1-y). Thus we only need a u32 to store them for all 1185 * choices of y < 1-2^(-32)*1024. 1186 * running_avg_sum reflects the time that the sched_entity is 1187 * effectively running on the CPU. 1188 * runnable_avg_sum represents the amount of time a sched_entity is on 1189 * a runqueue which includes the running time that is monitored by 1190 * running_avg_sum. 1191 */ 1192 u32 runnable_avg_sum, avg_period, running_avg_sum; 1193 }; 1194 1195 #ifdef CONFIG_SCHEDSTATS 1196 struct sched_statistics { 1197 u64 wait_start; 1198 u64 wait_max; 1199 u64 wait_count; 1200 u64 wait_sum; 1201 u64 iowait_count; 1202 u64 iowait_sum; 1203 1204 u64 sleep_start; 1205 u64 sleep_max; 1206 s64 sum_sleep_runtime; 1207 1208 u64 block_start; 1209 u64 block_max; 1210 u64 exec_max; 1211 u64 slice_max; 1212 1213 u64 nr_migrations_cold; 1214 u64 nr_failed_migrations_affine; 1215 u64 nr_failed_migrations_running; 1216 u64 nr_failed_migrations_hot; 1217 u64 nr_forced_migrations; 1218 1219 u64 nr_wakeups; 1220 u64 nr_wakeups_sync; 1221 u64 nr_wakeups_migrate; 1222 u64 nr_wakeups_local; 1223 u64 nr_wakeups_remote; 1224 u64 nr_wakeups_affine; 1225 u64 nr_wakeups_affine_attempts; 1226 u64 nr_wakeups_passive; 1227 u64 nr_wakeups_idle; 1228 }; 1229 #endif 1230 1231 struct sched_entity { 1232 struct load_weight load; /* for load-balancing */ 1233 struct rb_node run_node; 1234 struct list_head group_node; 1235 unsigned int on_rq; 1236 1237 u64 exec_start; 1238 u64 sum_exec_runtime; 1239 u64 vruntime; 1240 u64 prev_sum_exec_runtime; 1241 1242 u64 nr_migrations; 1243 1244 #ifdef CONFIG_SCHEDSTATS 1245 struct sched_statistics statistics; 1246 #endif 1247 1248 #ifdef CONFIG_FAIR_GROUP_SCHED 1249 int depth; 1250 struct sched_entity *parent; 1251 /* rq on which this entity is (to be) queued: */ 1252 struct cfs_rq *cfs_rq; 1253 /* rq "owned" by this entity/group: */ 1254 struct cfs_rq *my_q; 1255 #endif 1256 1257 #ifdef CONFIG_SMP 1258 /* Per-entity load-tracking */ 1259 struct sched_avg avg; 1260 #endif 1261 }; 1262 1263 struct sched_rt_entity { 1264 struct list_head run_list; 1265 unsigned long timeout; 1266 unsigned long watchdog_stamp; 1267 unsigned int time_slice; 1268 1269 struct sched_rt_entity *back; 1270 #ifdef CONFIG_RT_GROUP_SCHED 1271 struct sched_rt_entity *parent; 1272 /* rq on which this entity is (to be) queued: */ 1273 struct rt_rq *rt_rq; 1274 /* rq "owned" by this entity/group: */ 1275 struct rt_rq *my_q; 1276 #endif 1277 }; 1278 1279 struct sched_dl_entity { 1280 struct rb_node rb_node; 1281 1282 /* 1283 * Original scheduling parameters. Copied here from sched_attr 1284 * during sched_setattr(), they will remain the same until 1285 * the next sched_setattr(). 1286 */ 1287 u64 dl_runtime; /* maximum runtime for each instance */ 1288 u64 dl_deadline; /* relative deadline of each instance */ 1289 u64 dl_period; /* separation of two instances (period) */ 1290 u64 dl_bw; /* dl_runtime / dl_deadline */ 1291 1292 /* 1293 * Actual scheduling parameters. Initialized with the values above, 1294 * they are continously updated during task execution. Note that 1295 * the remaining runtime could be < 0 in case we are in overrun. 1296 */ 1297 s64 runtime; /* remaining runtime for this instance */ 1298 u64 deadline; /* absolute deadline for this instance */ 1299 unsigned int flags; /* specifying the scheduler behaviour */ 1300 1301 /* 1302 * Some bool flags: 1303 * 1304 * @dl_throttled tells if we exhausted the runtime. If so, the 1305 * task has to wait for a replenishment to be performed at the 1306 * next firing of dl_timer. 1307 * 1308 * @dl_new tells if a new instance arrived. If so we must 1309 * start executing it with full runtime and reset its absolute 1310 * deadline; 1311 * 1312 * @dl_boosted tells if we are boosted due to DI. If so we are 1313 * outside bandwidth enforcement mechanism (but only until we 1314 * exit the critical section); 1315 * 1316 * @dl_yielded tells if task gave up the cpu before consuming 1317 * all its available runtime during the last job. 1318 */ 1319 int dl_throttled, dl_new, dl_boosted, dl_yielded; 1320 1321 /* 1322 * Bandwidth enforcement timer. Each -deadline task has its 1323 * own bandwidth to be enforced, thus we need one timer per task. 1324 */ 1325 struct hrtimer dl_timer; 1326 }; 1327 1328 union rcu_special { 1329 struct { 1330 bool blocked; 1331 bool need_qs; 1332 } b; 1333 short s; 1334 }; 1335 struct rcu_node; 1336 1337 enum perf_event_task_context { 1338 perf_invalid_context = -1, 1339 perf_hw_context = 0, 1340 perf_sw_context, 1341 perf_nr_task_contexts, 1342 }; 1343 1344 struct task_struct { 1345 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1346 void *stack; 1347 atomic_t usage; 1348 unsigned int flags; /* per process flags, defined below */ 1349 unsigned int ptrace; 1350 1351 #ifdef CONFIG_SMP 1352 struct llist_node wake_entry; 1353 int on_cpu; 1354 struct task_struct *last_wakee; 1355 unsigned long wakee_flips; 1356 unsigned long wakee_flip_decay_ts; 1357 1358 int wake_cpu; 1359 #endif 1360 int on_rq; 1361 1362 int prio, static_prio, normal_prio; 1363 unsigned int rt_priority; 1364 const struct sched_class *sched_class; 1365 struct sched_entity se; 1366 struct sched_rt_entity rt; 1367 #ifdef CONFIG_CGROUP_SCHED 1368 struct task_group *sched_task_group; 1369 #endif 1370 struct sched_dl_entity dl; 1371 1372 #ifdef CONFIG_PREEMPT_NOTIFIERS 1373 /* list of struct preempt_notifier: */ 1374 struct hlist_head preempt_notifiers; 1375 #endif 1376 1377 #ifdef CONFIG_BLK_DEV_IO_TRACE 1378 unsigned int btrace_seq; 1379 #endif 1380 1381 unsigned int policy; 1382 int nr_cpus_allowed; 1383 cpumask_t cpus_allowed; 1384 1385 #ifdef CONFIG_PREEMPT_RCU 1386 int rcu_read_lock_nesting; 1387 union rcu_special rcu_read_unlock_special; 1388 struct list_head rcu_node_entry; 1389 struct rcu_node *rcu_blocked_node; 1390 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1391 #ifdef CONFIG_TASKS_RCU 1392 unsigned long rcu_tasks_nvcsw; 1393 bool rcu_tasks_holdout; 1394 struct list_head rcu_tasks_holdout_list; 1395 int rcu_tasks_idle_cpu; 1396 #endif /* #ifdef CONFIG_TASKS_RCU */ 1397 1398 #ifdef CONFIG_SCHED_INFO 1399 struct sched_info sched_info; 1400 #endif 1401 1402 struct list_head tasks; 1403 #ifdef CONFIG_SMP 1404 struct plist_node pushable_tasks; 1405 struct rb_node pushable_dl_tasks; 1406 #endif 1407 1408 struct mm_struct *mm, *active_mm; 1409 /* per-thread vma caching */ 1410 u32 vmacache_seqnum; 1411 struct vm_area_struct *vmacache[VMACACHE_SIZE]; 1412 #if defined(SPLIT_RSS_COUNTING) 1413 struct task_rss_stat rss_stat; 1414 #endif 1415 /* task state */ 1416 int exit_state; 1417 int exit_code, exit_signal; 1418 int pdeath_signal; /* The signal sent when the parent dies */ 1419 unsigned long jobctl; /* JOBCTL_*, siglock protected */ 1420 1421 /* Used for emulating ABI behavior of previous Linux versions */ 1422 unsigned int personality; 1423 1424 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1425 * execve */ 1426 unsigned in_iowait:1; 1427 1428 /* Revert to default priority/policy when forking */ 1429 unsigned sched_reset_on_fork:1; 1430 unsigned sched_contributes_to_load:1; 1431 unsigned sched_migrated:1; 1432 1433 #ifdef CONFIG_MEMCG_KMEM 1434 unsigned memcg_kmem_skip_account:1; 1435 #endif 1436 #ifdef CONFIG_COMPAT_BRK 1437 unsigned brk_randomized:1; 1438 #endif 1439 1440 unsigned long atomic_flags; /* Flags needing atomic access. */ 1441 1442 struct restart_block restart_block; 1443 1444 pid_t pid; 1445 pid_t tgid; 1446 1447 #ifdef CONFIG_CC_STACKPROTECTOR 1448 /* Canary value for the -fstack-protector gcc feature */ 1449 unsigned long stack_canary; 1450 #endif 1451 /* 1452 * pointers to (original) parent process, youngest child, younger sibling, 1453 * older sibling, respectively. (p->father can be replaced with 1454 * p->real_parent->pid) 1455 */ 1456 struct task_struct __rcu *real_parent; /* real parent process */ 1457 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1458 /* 1459 * children/sibling forms the list of my natural children 1460 */ 1461 struct list_head children; /* list of my children */ 1462 struct list_head sibling; /* linkage in my parent's children list */ 1463 struct task_struct *group_leader; /* threadgroup leader */ 1464 1465 /* 1466 * ptraced is the list of tasks this task is using ptrace on. 1467 * This includes both natural children and PTRACE_ATTACH targets. 1468 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1469 */ 1470 struct list_head ptraced; 1471 struct list_head ptrace_entry; 1472 1473 /* PID/PID hash table linkage. */ 1474 struct pid_link pids[PIDTYPE_MAX]; 1475 struct list_head thread_group; 1476 struct list_head thread_node; 1477 1478 struct completion *vfork_done; /* for vfork() */ 1479 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1480 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1481 1482 cputime_t utime, stime, utimescaled, stimescaled; 1483 cputime_t gtime; 1484 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 1485 struct cputime prev_cputime; 1486 #endif 1487 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1488 seqlock_t vtime_seqlock; 1489 unsigned long long vtime_snap; 1490 enum { 1491 VTIME_SLEEPING = 0, 1492 VTIME_USER, 1493 VTIME_SYS, 1494 } vtime_snap_whence; 1495 #endif 1496 unsigned long nvcsw, nivcsw; /* context switch counts */ 1497 u64 start_time; /* monotonic time in nsec */ 1498 u64 real_start_time; /* boot based time in nsec */ 1499 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1500 unsigned long min_flt, maj_flt; 1501 1502 struct task_cputime cputime_expires; 1503 struct list_head cpu_timers[3]; 1504 1505 /* process credentials */ 1506 const struct cred __rcu *real_cred; /* objective and real subjective task 1507 * credentials (COW) */ 1508 const struct cred __rcu *cred; /* effective (overridable) subjective task 1509 * credentials (COW) */ 1510 char comm[TASK_COMM_LEN]; /* executable name excluding path 1511 - access with [gs]et_task_comm (which lock 1512 it with task_lock()) 1513 - initialized normally by setup_new_exec */ 1514 /* file system info */ 1515 struct nameidata *nameidata; 1516 #ifdef CONFIG_SYSVIPC 1517 /* ipc stuff */ 1518 struct sysv_sem sysvsem; 1519 struct sysv_shm sysvshm; 1520 #endif 1521 #ifdef CONFIG_DETECT_HUNG_TASK 1522 /* hung task detection */ 1523 unsigned long last_switch_count; 1524 #endif 1525 /* CPU-specific state of this task */ 1526 struct thread_struct thread; 1527 /* filesystem information */ 1528 struct fs_struct *fs; 1529 /* open file information */ 1530 struct files_struct *files; 1531 /* namespaces */ 1532 struct nsproxy *nsproxy; 1533 /* signal handlers */ 1534 struct signal_struct *signal; 1535 struct sighand_struct *sighand; 1536 1537 sigset_t blocked, real_blocked; 1538 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1539 struct sigpending pending; 1540 1541 unsigned long sas_ss_sp; 1542 size_t sas_ss_size; 1543 int (*notifier)(void *priv); 1544 void *notifier_data; 1545 sigset_t *notifier_mask; 1546 struct callback_head *task_works; 1547 1548 struct audit_context *audit_context; 1549 #ifdef CONFIG_AUDITSYSCALL 1550 kuid_t loginuid; 1551 unsigned int sessionid; 1552 #endif 1553 struct seccomp seccomp; 1554 1555 /* Thread group tracking */ 1556 u32 parent_exec_id; 1557 u32 self_exec_id; 1558 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1559 * mempolicy */ 1560 spinlock_t alloc_lock; 1561 1562 /* Protection of the PI data structures: */ 1563 raw_spinlock_t pi_lock; 1564 1565 struct wake_q_node wake_q; 1566 1567 #ifdef CONFIG_RT_MUTEXES 1568 /* PI waiters blocked on a rt_mutex held by this task */ 1569 struct rb_root pi_waiters; 1570 struct rb_node *pi_waiters_leftmost; 1571 /* Deadlock detection and priority inheritance handling */ 1572 struct rt_mutex_waiter *pi_blocked_on; 1573 #endif 1574 1575 #ifdef CONFIG_DEBUG_MUTEXES 1576 /* mutex deadlock detection */ 1577 struct mutex_waiter *blocked_on; 1578 #endif 1579 #ifdef CONFIG_TRACE_IRQFLAGS 1580 unsigned int irq_events; 1581 unsigned long hardirq_enable_ip; 1582 unsigned long hardirq_disable_ip; 1583 unsigned int hardirq_enable_event; 1584 unsigned int hardirq_disable_event; 1585 int hardirqs_enabled; 1586 int hardirq_context; 1587 unsigned long softirq_disable_ip; 1588 unsigned long softirq_enable_ip; 1589 unsigned int softirq_disable_event; 1590 unsigned int softirq_enable_event; 1591 int softirqs_enabled; 1592 int softirq_context; 1593 #endif 1594 #ifdef CONFIG_LOCKDEP 1595 # define MAX_LOCK_DEPTH 48UL 1596 u64 curr_chain_key; 1597 int lockdep_depth; 1598 unsigned int lockdep_recursion; 1599 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1600 gfp_t lockdep_reclaim_gfp; 1601 #endif 1602 1603 /* journalling filesystem info */ 1604 void *journal_info; 1605 1606 /* stacked block device info */ 1607 struct bio_list *bio_list; 1608 1609 #ifdef CONFIG_BLOCK 1610 /* stack plugging */ 1611 struct blk_plug *plug; 1612 #endif 1613 1614 /* VM state */ 1615 struct reclaim_state *reclaim_state; 1616 1617 struct backing_dev_info *backing_dev_info; 1618 1619 struct io_context *io_context; 1620 1621 unsigned long ptrace_message; 1622 siginfo_t *last_siginfo; /* For ptrace use. */ 1623 struct task_io_accounting ioac; 1624 #if defined(CONFIG_TASK_XACCT) 1625 u64 acct_rss_mem1; /* accumulated rss usage */ 1626 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1627 cputime_t acct_timexpd; /* stime + utime since last update */ 1628 #endif 1629 #ifdef CONFIG_CPUSETS 1630 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1631 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1632 int cpuset_mem_spread_rotor; 1633 int cpuset_slab_spread_rotor; 1634 #endif 1635 #ifdef CONFIG_CGROUPS 1636 /* Control Group info protected by css_set_lock */ 1637 struct css_set __rcu *cgroups; 1638 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1639 struct list_head cg_list; 1640 #endif 1641 #ifdef CONFIG_FUTEX 1642 struct robust_list_head __user *robust_list; 1643 #ifdef CONFIG_COMPAT 1644 struct compat_robust_list_head __user *compat_robust_list; 1645 #endif 1646 struct list_head pi_state_list; 1647 struct futex_pi_state *pi_state_cache; 1648 #endif 1649 #ifdef CONFIG_PERF_EVENTS 1650 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1651 struct mutex perf_event_mutex; 1652 struct list_head perf_event_list; 1653 #endif 1654 #ifdef CONFIG_DEBUG_PREEMPT 1655 unsigned long preempt_disable_ip; 1656 #endif 1657 #ifdef CONFIG_NUMA 1658 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1659 short il_next; 1660 short pref_node_fork; 1661 #endif 1662 #ifdef CONFIG_NUMA_BALANCING 1663 int numa_scan_seq; 1664 unsigned int numa_scan_period; 1665 unsigned int numa_scan_period_max; 1666 int numa_preferred_nid; 1667 unsigned long numa_migrate_retry; 1668 u64 node_stamp; /* migration stamp */ 1669 u64 last_task_numa_placement; 1670 u64 last_sum_exec_runtime; 1671 struct callback_head numa_work; 1672 1673 struct list_head numa_entry; 1674 struct numa_group *numa_group; 1675 1676 /* 1677 * numa_faults is an array split into four regions: 1678 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1679 * in this precise order. 1680 * 1681 * faults_memory: Exponential decaying average of faults on a per-node 1682 * basis. Scheduling placement decisions are made based on these 1683 * counts. The values remain static for the duration of a PTE scan. 1684 * faults_cpu: Track the nodes the process was running on when a NUMA 1685 * hinting fault was incurred. 1686 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1687 * during the current scan window. When the scan completes, the counts 1688 * in faults_memory and faults_cpu decay and these values are copied. 1689 */ 1690 unsigned long *numa_faults; 1691 unsigned long total_numa_faults; 1692 1693 /* 1694 * numa_faults_locality tracks if faults recorded during the last 1695 * scan window were remote/local or failed to migrate. The task scan 1696 * period is adapted based on the locality of the faults with different 1697 * weights depending on whether they were shared or private faults 1698 */ 1699 unsigned long numa_faults_locality[3]; 1700 1701 unsigned long numa_pages_migrated; 1702 #endif /* CONFIG_NUMA_BALANCING */ 1703 1704 struct rcu_head rcu; 1705 1706 /* 1707 * cache last used pipe for splice 1708 */ 1709 struct pipe_inode_info *splice_pipe; 1710 1711 struct page_frag task_frag; 1712 1713 #ifdef CONFIG_TASK_DELAY_ACCT 1714 struct task_delay_info *delays; 1715 #endif 1716 #ifdef CONFIG_FAULT_INJECTION 1717 int make_it_fail; 1718 #endif 1719 /* 1720 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1721 * balance_dirty_pages() for some dirty throttling pause 1722 */ 1723 int nr_dirtied; 1724 int nr_dirtied_pause; 1725 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1726 1727 #ifdef CONFIG_LATENCYTOP 1728 int latency_record_count; 1729 struct latency_record latency_record[LT_SAVECOUNT]; 1730 #endif 1731 /* 1732 * time slack values; these are used to round up poll() and 1733 * select() etc timeout values. These are in nanoseconds. 1734 */ 1735 unsigned long timer_slack_ns; 1736 unsigned long default_timer_slack_ns; 1737 1738 #ifdef CONFIG_KASAN 1739 unsigned int kasan_depth; 1740 #endif 1741 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1742 /* Index of current stored address in ret_stack */ 1743 int curr_ret_stack; 1744 /* Stack of return addresses for return function tracing */ 1745 struct ftrace_ret_stack *ret_stack; 1746 /* time stamp for last schedule */ 1747 unsigned long long ftrace_timestamp; 1748 /* 1749 * Number of functions that haven't been traced 1750 * because of depth overrun. 1751 */ 1752 atomic_t trace_overrun; 1753 /* Pause for the tracing */ 1754 atomic_t tracing_graph_pause; 1755 #endif 1756 #ifdef CONFIG_TRACING 1757 /* state flags for use by tracers */ 1758 unsigned long trace; 1759 /* bitmask and counter of trace recursion */ 1760 unsigned long trace_recursion; 1761 #endif /* CONFIG_TRACING */ 1762 #ifdef CONFIG_MEMCG 1763 struct memcg_oom_info { 1764 struct mem_cgroup *memcg; 1765 gfp_t gfp_mask; 1766 int order; 1767 unsigned int may_oom:1; 1768 } memcg_oom; 1769 #endif 1770 #ifdef CONFIG_UPROBES 1771 struct uprobe_task *utask; 1772 #endif 1773 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1774 unsigned int sequential_io; 1775 unsigned int sequential_io_avg; 1776 #endif 1777 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1778 unsigned long task_state_change; 1779 #endif 1780 int pagefault_disabled; 1781 }; 1782 1783 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1784 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1785 1786 #define TNF_MIGRATED 0x01 1787 #define TNF_NO_GROUP 0x02 1788 #define TNF_SHARED 0x04 1789 #define TNF_FAULT_LOCAL 0x08 1790 #define TNF_MIGRATE_FAIL 0x10 1791 1792 #ifdef CONFIG_NUMA_BALANCING 1793 extern void task_numa_fault(int last_node, int node, int pages, int flags); 1794 extern pid_t task_numa_group_id(struct task_struct *p); 1795 extern void set_numabalancing_state(bool enabled); 1796 extern void task_numa_free(struct task_struct *p); 1797 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page, 1798 int src_nid, int dst_cpu); 1799 #else 1800 static inline void task_numa_fault(int last_node, int node, int pages, 1801 int flags) 1802 { 1803 } 1804 static inline pid_t task_numa_group_id(struct task_struct *p) 1805 { 1806 return 0; 1807 } 1808 static inline void set_numabalancing_state(bool enabled) 1809 { 1810 } 1811 static inline void task_numa_free(struct task_struct *p) 1812 { 1813 } 1814 static inline bool should_numa_migrate_memory(struct task_struct *p, 1815 struct page *page, int src_nid, int dst_cpu) 1816 { 1817 return true; 1818 } 1819 #endif 1820 1821 static inline struct pid *task_pid(struct task_struct *task) 1822 { 1823 return task->pids[PIDTYPE_PID].pid; 1824 } 1825 1826 static inline struct pid *task_tgid(struct task_struct *task) 1827 { 1828 return task->group_leader->pids[PIDTYPE_PID].pid; 1829 } 1830 1831 /* 1832 * Without tasklist or rcu lock it is not safe to dereference 1833 * the result of task_pgrp/task_session even if task == current, 1834 * we can race with another thread doing sys_setsid/sys_setpgid. 1835 */ 1836 static inline struct pid *task_pgrp(struct task_struct *task) 1837 { 1838 return task->group_leader->pids[PIDTYPE_PGID].pid; 1839 } 1840 1841 static inline struct pid *task_session(struct task_struct *task) 1842 { 1843 return task->group_leader->pids[PIDTYPE_SID].pid; 1844 } 1845 1846 struct pid_namespace; 1847 1848 /* 1849 * the helpers to get the task's different pids as they are seen 1850 * from various namespaces 1851 * 1852 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1853 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1854 * current. 1855 * task_xid_nr_ns() : id seen from the ns specified; 1856 * 1857 * set_task_vxid() : assigns a virtual id to a task; 1858 * 1859 * see also pid_nr() etc in include/linux/pid.h 1860 */ 1861 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1862 struct pid_namespace *ns); 1863 1864 static inline pid_t task_pid_nr(struct task_struct *tsk) 1865 { 1866 return tsk->pid; 1867 } 1868 1869 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1870 struct pid_namespace *ns) 1871 { 1872 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1873 } 1874 1875 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1876 { 1877 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1878 } 1879 1880 1881 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1882 { 1883 return tsk->tgid; 1884 } 1885 1886 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1887 1888 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1889 { 1890 return pid_vnr(task_tgid(tsk)); 1891 } 1892 1893 1894 static inline int pid_alive(const struct task_struct *p); 1895 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 1896 { 1897 pid_t pid = 0; 1898 1899 rcu_read_lock(); 1900 if (pid_alive(tsk)) 1901 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 1902 rcu_read_unlock(); 1903 1904 return pid; 1905 } 1906 1907 static inline pid_t task_ppid_nr(const struct task_struct *tsk) 1908 { 1909 return task_ppid_nr_ns(tsk, &init_pid_ns); 1910 } 1911 1912 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1913 struct pid_namespace *ns) 1914 { 1915 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1916 } 1917 1918 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1919 { 1920 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1921 } 1922 1923 1924 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1925 struct pid_namespace *ns) 1926 { 1927 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1928 } 1929 1930 static inline pid_t task_session_vnr(struct task_struct *tsk) 1931 { 1932 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1933 } 1934 1935 /* obsolete, do not use */ 1936 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1937 { 1938 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1939 } 1940 1941 /** 1942 * pid_alive - check that a task structure is not stale 1943 * @p: Task structure to be checked. 1944 * 1945 * Test if a process is not yet dead (at most zombie state) 1946 * If pid_alive fails, then pointers within the task structure 1947 * can be stale and must not be dereferenced. 1948 * 1949 * Return: 1 if the process is alive. 0 otherwise. 1950 */ 1951 static inline int pid_alive(const struct task_struct *p) 1952 { 1953 return p->pids[PIDTYPE_PID].pid != NULL; 1954 } 1955 1956 /** 1957 * is_global_init - check if a task structure is init 1958 * @tsk: Task structure to be checked. 1959 * 1960 * Check if a task structure is the first user space task the kernel created. 1961 * 1962 * Return: 1 if the task structure is init. 0 otherwise. 1963 */ 1964 static inline int is_global_init(struct task_struct *tsk) 1965 { 1966 return tsk->pid == 1; 1967 } 1968 1969 extern struct pid *cad_pid; 1970 1971 extern void free_task(struct task_struct *tsk); 1972 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1973 1974 extern void __put_task_struct(struct task_struct *t); 1975 1976 static inline void put_task_struct(struct task_struct *t) 1977 { 1978 if (atomic_dec_and_test(&t->usage)) 1979 __put_task_struct(t); 1980 } 1981 1982 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1983 extern void task_cputime(struct task_struct *t, 1984 cputime_t *utime, cputime_t *stime); 1985 extern void task_cputime_scaled(struct task_struct *t, 1986 cputime_t *utimescaled, cputime_t *stimescaled); 1987 extern cputime_t task_gtime(struct task_struct *t); 1988 #else 1989 static inline void task_cputime(struct task_struct *t, 1990 cputime_t *utime, cputime_t *stime) 1991 { 1992 if (utime) 1993 *utime = t->utime; 1994 if (stime) 1995 *stime = t->stime; 1996 } 1997 1998 static inline void task_cputime_scaled(struct task_struct *t, 1999 cputime_t *utimescaled, 2000 cputime_t *stimescaled) 2001 { 2002 if (utimescaled) 2003 *utimescaled = t->utimescaled; 2004 if (stimescaled) 2005 *stimescaled = t->stimescaled; 2006 } 2007 2008 static inline cputime_t task_gtime(struct task_struct *t) 2009 { 2010 return t->gtime; 2011 } 2012 #endif 2013 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2014 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2015 2016 /* 2017 * Per process flags 2018 */ 2019 #define PF_EXITING 0x00000004 /* getting shut down */ 2020 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 2021 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 2022 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 2023 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 2024 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 2025 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 2026 #define PF_DUMPCORE 0x00000200 /* dumped core */ 2027 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 2028 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 2029 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 2030 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 2031 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 2032 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 2033 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 2034 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 2035 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 2036 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 2037 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 2038 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 2039 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 2040 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 2041 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 2042 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 2043 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 2044 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 2045 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 2046 2047 /* 2048 * Only the _current_ task can read/write to tsk->flags, but other 2049 * tasks can access tsk->flags in readonly mode for example 2050 * with tsk_used_math (like during threaded core dumping). 2051 * There is however an exception to this rule during ptrace 2052 * or during fork: the ptracer task is allowed to write to the 2053 * child->flags of its traced child (same goes for fork, the parent 2054 * can write to the child->flags), because we're guaranteed the 2055 * child is not running and in turn not changing child->flags 2056 * at the same time the parent does it. 2057 */ 2058 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 2059 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 2060 #define clear_used_math() clear_stopped_child_used_math(current) 2061 #define set_used_math() set_stopped_child_used_math(current) 2062 #define conditional_stopped_child_used_math(condition, child) \ 2063 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 2064 #define conditional_used_math(condition) \ 2065 conditional_stopped_child_used_math(condition, current) 2066 #define copy_to_stopped_child_used_math(child) \ 2067 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 2068 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 2069 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 2070 #define used_math() tsk_used_math(current) 2071 2072 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags 2073 * __GFP_FS is also cleared as it implies __GFP_IO. 2074 */ 2075 static inline gfp_t memalloc_noio_flags(gfp_t flags) 2076 { 2077 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 2078 flags &= ~(__GFP_IO | __GFP_FS); 2079 return flags; 2080 } 2081 2082 static inline unsigned int memalloc_noio_save(void) 2083 { 2084 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 2085 current->flags |= PF_MEMALLOC_NOIO; 2086 return flags; 2087 } 2088 2089 static inline void memalloc_noio_restore(unsigned int flags) 2090 { 2091 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 2092 } 2093 2094 /* Per-process atomic flags. */ 2095 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 2096 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 2097 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 2098 2099 2100 #define TASK_PFA_TEST(name, func) \ 2101 static inline bool task_##func(struct task_struct *p) \ 2102 { return test_bit(PFA_##name, &p->atomic_flags); } 2103 #define TASK_PFA_SET(name, func) \ 2104 static inline void task_set_##func(struct task_struct *p) \ 2105 { set_bit(PFA_##name, &p->atomic_flags); } 2106 #define TASK_PFA_CLEAR(name, func) \ 2107 static inline void task_clear_##func(struct task_struct *p) \ 2108 { clear_bit(PFA_##name, &p->atomic_flags); } 2109 2110 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 2111 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 2112 2113 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 2114 TASK_PFA_SET(SPREAD_PAGE, spread_page) 2115 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 2116 2117 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 2118 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 2119 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 2120 2121 /* 2122 * task->jobctl flags 2123 */ 2124 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 2125 2126 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 2127 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 2128 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 2129 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 2130 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 2131 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 2132 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 2133 2134 #define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT) 2135 #define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT) 2136 #define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT) 2137 #define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT) 2138 #define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT) 2139 #define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT) 2140 #define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT) 2141 2142 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 2143 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 2144 2145 extern bool task_set_jobctl_pending(struct task_struct *task, 2146 unsigned long mask); 2147 extern void task_clear_jobctl_trapping(struct task_struct *task); 2148 extern void task_clear_jobctl_pending(struct task_struct *task, 2149 unsigned long mask); 2150 2151 static inline void rcu_copy_process(struct task_struct *p) 2152 { 2153 #ifdef CONFIG_PREEMPT_RCU 2154 p->rcu_read_lock_nesting = 0; 2155 p->rcu_read_unlock_special.s = 0; 2156 p->rcu_blocked_node = NULL; 2157 INIT_LIST_HEAD(&p->rcu_node_entry); 2158 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 2159 #ifdef CONFIG_TASKS_RCU 2160 p->rcu_tasks_holdout = false; 2161 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); 2162 p->rcu_tasks_idle_cpu = -1; 2163 #endif /* #ifdef CONFIG_TASKS_RCU */ 2164 } 2165 2166 static inline void tsk_restore_flags(struct task_struct *task, 2167 unsigned long orig_flags, unsigned long flags) 2168 { 2169 task->flags &= ~flags; 2170 task->flags |= orig_flags & flags; 2171 } 2172 2173 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, 2174 const struct cpumask *trial); 2175 extern int task_can_attach(struct task_struct *p, 2176 const struct cpumask *cs_cpus_allowed); 2177 #ifdef CONFIG_SMP 2178 extern void do_set_cpus_allowed(struct task_struct *p, 2179 const struct cpumask *new_mask); 2180 2181 extern int set_cpus_allowed_ptr(struct task_struct *p, 2182 const struct cpumask *new_mask); 2183 #else 2184 static inline void do_set_cpus_allowed(struct task_struct *p, 2185 const struct cpumask *new_mask) 2186 { 2187 } 2188 static inline int set_cpus_allowed_ptr(struct task_struct *p, 2189 const struct cpumask *new_mask) 2190 { 2191 if (!cpumask_test_cpu(0, new_mask)) 2192 return -EINVAL; 2193 return 0; 2194 } 2195 #endif 2196 2197 #ifdef CONFIG_NO_HZ_COMMON 2198 void calc_load_enter_idle(void); 2199 void calc_load_exit_idle(void); 2200 #else 2201 static inline void calc_load_enter_idle(void) { } 2202 static inline void calc_load_exit_idle(void) { } 2203 #endif /* CONFIG_NO_HZ_COMMON */ 2204 2205 #ifndef CONFIG_CPUMASK_OFFSTACK 2206 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 2207 { 2208 return set_cpus_allowed_ptr(p, &new_mask); 2209 } 2210 #endif 2211 2212 /* 2213 * Do not use outside of architecture code which knows its limitations. 2214 * 2215 * sched_clock() has no promise of monotonicity or bounded drift between 2216 * CPUs, use (which you should not) requires disabling IRQs. 2217 * 2218 * Please use one of the three interfaces below. 2219 */ 2220 extern unsigned long long notrace sched_clock(void); 2221 /* 2222 * See the comment in kernel/sched/clock.c 2223 */ 2224 extern u64 cpu_clock(int cpu); 2225 extern u64 local_clock(void); 2226 extern u64 running_clock(void); 2227 extern u64 sched_clock_cpu(int cpu); 2228 2229 2230 extern void sched_clock_init(void); 2231 2232 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2233 static inline void sched_clock_tick(void) 2234 { 2235 } 2236 2237 static inline void sched_clock_idle_sleep_event(void) 2238 { 2239 } 2240 2241 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 2242 { 2243 } 2244 #else 2245 /* 2246 * Architectures can set this to 1 if they have specified 2247 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 2248 * but then during bootup it turns out that sched_clock() 2249 * is reliable after all: 2250 */ 2251 extern int sched_clock_stable(void); 2252 extern void set_sched_clock_stable(void); 2253 extern void clear_sched_clock_stable(void); 2254 2255 extern void sched_clock_tick(void); 2256 extern void sched_clock_idle_sleep_event(void); 2257 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2258 #endif 2259 2260 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2261 /* 2262 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 2263 * The reason for this explicit opt-in is not to have perf penalty with 2264 * slow sched_clocks. 2265 */ 2266 extern void enable_sched_clock_irqtime(void); 2267 extern void disable_sched_clock_irqtime(void); 2268 #else 2269 static inline void enable_sched_clock_irqtime(void) {} 2270 static inline void disable_sched_clock_irqtime(void) {} 2271 #endif 2272 2273 extern unsigned long long 2274 task_sched_runtime(struct task_struct *task); 2275 2276 /* sched_exec is called by processes performing an exec */ 2277 #ifdef CONFIG_SMP 2278 extern void sched_exec(void); 2279 #else 2280 #define sched_exec() {} 2281 #endif 2282 2283 extern void sched_clock_idle_sleep_event(void); 2284 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2285 2286 #ifdef CONFIG_HOTPLUG_CPU 2287 extern void idle_task_exit(void); 2288 #else 2289 static inline void idle_task_exit(void) {} 2290 #endif 2291 2292 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 2293 extern void wake_up_nohz_cpu(int cpu); 2294 #else 2295 static inline void wake_up_nohz_cpu(int cpu) { } 2296 #endif 2297 2298 #ifdef CONFIG_NO_HZ_FULL 2299 extern bool sched_can_stop_tick(void); 2300 extern u64 scheduler_tick_max_deferment(void); 2301 #else 2302 static inline bool sched_can_stop_tick(void) { return false; } 2303 #endif 2304 2305 #ifdef CONFIG_SCHED_AUTOGROUP 2306 extern void sched_autogroup_create_attach(struct task_struct *p); 2307 extern void sched_autogroup_detach(struct task_struct *p); 2308 extern void sched_autogroup_fork(struct signal_struct *sig); 2309 extern void sched_autogroup_exit(struct signal_struct *sig); 2310 #ifdef CONFIG_PROC_FS 2311 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2312 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2313 #endif 2314 #else 2315 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2316 static inline void sched_autogroup_detach(struct task_struct *p) { } 2317 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2318 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2319 #endif 2320 2321 extern int yield_to(struct task_struct *p, bool preempt); 2322 extern void set_user_nice(struct task_struct *p, long nice); 2323 extern int task_prio(const struct task_struct *p); 2324 /** 2325 * task_nice - return the nice value of a given task. 2326 * @p: the task in question. 2327 * 2328 * Return: The nice value [ -20 ... 0 ... 19 ]. 2329 */ 2330 static inline int task_nice(const struct task_struct *p) 2331 { 2332 return PRIO_TO_NICE((p)->static_prio); 2333 } 2334 extern int can_nice(const struct task_struct *p, const int nice); 2335 extern int task_curr(const struct task_struct *p); 2336 extern int idle_cpu(int cpu); 2337 extern int sched_setscheduler(struct task_struct *, int, 2338 const struct sched_param *); 2339 extern int sched_setscheduler_nocheck(struct task_struct *, int, 2340 const struct sched_param *); 2341 extern int sched_setattr(struct task_struct *, 2342 const struct sched_attr *); 2343 extern struct task_struct *idle_task(int cpu); 2344 /** 2345 * is_idle_task - is the specified task an idle task? 2346 * @p: the task in question. 2347 * 2348 * Return: 1 if @p is an idle task. 0 otherwise. 2349 */ 2350 static inline bool is_idle_task(const struct task_struct *p) 2351 { 2352 return p->pid == 0; 2353 } 2354 extern struct task_struct *curr_task(int cpu); 2355 extern void set_curr_task(int cpu, struct task_struct *p); 2356 2357 void yield(void); 2358 2359 union thread_union { 2360 struct thread_info thread_info; 2361 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2362 }; 2363 2364 #ifndef __HAVE_ARCH_KSTACK_END 2365 static inline int kstack_end(void *addr) 2366 { 2367 /* Reliable end of stack detection: 2368 * Some APM bios versions misalign the stack 2369 */ 2370 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2371 } 2372 #endif 2373 2374 extern union thread_union init_thread_union; 2375 extern struct task_struct init_task; 2376 2377 extern struct mm_struct init_mm; 2378 2379 extern struct pid_namespace init_pid_ns; 2380 2381 /* 2382 * find a task by one of its numerical ids 2383 * 2384 * find_task_by_pid_ns(): 2385 * finds a task by its pid in the specified namespace 2386 * find_task_by_vpid(): 2387 * finds a task by its virtual pid 2388 * 2389 * see also find_vpid() etc in include/linux/pid.h 2390 */ 2391 2392 extern struct task_struct *find_task_by_vpid(pid_t nr); 2393 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2394 struct pid_namespace *ns); 2395 2396 /* per-UID process charging. */ 2397 extern struct user_struct * alloc_uid(kuid_t); 2398 static inline struct user_struct *get_uid(struct user_struct *u) 2399 { 2400 atomic_inc(&u->__count); 2401 return u; 2402 } 2403 extern void free_uid(struct user_struct *); 2404 2405 #include <asm/current.h> 2406 2407 extern void xtime_update(unsigned long ticks); 2408 2409 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2410 extern int wake_up_process(struct task_struct *tsk); 2411 extern void wake_up_new_task(struct task_struct *tsk); 2412 #ifdef CONFIG_SMP 2413 extern void kick_process(struct task_struct *tsk); 2414 #else 2415 static inline void kick_process(struct task_struct *tsk) { } 2416 #endif 2417 extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 2418 extern void sched_dead(struct task_struct *p); 2419 2420 extern void proc_caches_init(void); 2421 extern void flush_signals(struct task_struct *); 2422 extern void ignore_signals(struct task_struct *); 2423 extern void flush_signal_handlers(struct task_struct *, int force_default); 2424 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2425 2426 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2427 { 2428 unsigned long flags; 2429 int ret; 2430 2431 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2432 ret = dequeue_signal(tsk, mask, info); 2433 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2434 2435 return ret; 2436 } 2437 2438 extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2439 sigset_t *mask); 2440 extern void unblock_all_signals(void); 2441 extern void release_task(struct task_struct * p); 2442 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2443 extern int force_sigsegv(int, struct task_struct *); 2444 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2445 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2446 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2447 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2448 const struct cred *, u32); 2449 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2450 extern int kill_pid(struct pid *pid, int sig, int priv); 2451 extern int kill_proc_info(int, struct siginfo *, pid_t); 2452 extern __must_check bool do_notify_parent(struct task_struct *, int); 2453 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2454 extern void force_sig(int, struct task_struct *); 2455 extern int send_sig(int, struct task_struct *, int); 2456 extern int zap_other_threads(struct task_struct *p); 2457 extern struct sigqueue *sigqueue_alloc(void); 2458 extern void sigqueue_free(struct sigqueue *); 2459 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2460 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2461 2462 static inline void restore_saved_sigmask(void) 2463 { 2464 if (test_and_clear_restore_sigmask()) 2465 __set_current_blocked(¤t->saved_sigmask); 2466 } 2467 2468 static inline sigset_t *sigmask_to_save(void) 2469 { 2470 sigset_t *res = ¤t->blocked; 2471 if (unlikely(test_restore_sigmask())) 2472 res = ¤t->saved_sigmask; 2473 return res; 2474 } 2475 2476 static inline int kill_cad_pid(int sig, int priv) 2477 { 2478 return kill_pid(cad_pid, sig, priv); 2479 } 2480 2481 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2482 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2483 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2484 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2485 2486 /* 2487 * True if we are on the alternate signal stack. 2488 */ 2489 static inline int on_sig_stack(unsigned long sp) 2490 { 2491 #ifdef CONFIG_STACK_GROWSUP 2492 return sp >= current->sas_ss_sp && 2493 sp - current->sas_ss_sp < current->sas_ss_size; 2494 #else 2495 return sp > current->sas_ss_sp && 2496 sp - current->sas_ss_sp <= current->sas_ss_size; 2497 #endif 2498 } 2499 2500 static inline int sas_ss_flags(unsigned long sp) 2501 { 2502 if (!current->sas_ss_size) 2503 return SS_DISABLE; 2504 2505 return on_sig_stack(sp) ? SS_ONSTACK : 0; 2506 } 2507 2508 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2509 { 2510 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2511 #ifdef CONFIG_STACK_GROWSUP 2512 return current->sas_ss_sp; 2513 #else 2514 return current->sas_ss_sp + current->sas_ss_size; 2515 #endif 2516 return sp; 2517 } 2518 2519 /* 2520 * Routines for handling mm_structs 2521 */ 2522 extern struct mm_struct * mm_alloc(void); 2523 2524 /* mmdrop drops the mm and the page tables */ 2525 extern void __mmdrop(struct mm_struct *); 2526 static inline void mmdrop(struct mm_struct * mm) 2527 { 2528 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2529 __mmdrop(mm); 2530 } 2531 2532 /* mmput gets rid of the mappings and all user-space */ 2533 extern void mmput(struct mm_struct *); 2534 /* Grab a reference to a task's mm, if it is not already going away */ 2535 extern struct mm_struct *get_task_mm(struct task_struct *task); 2536 /* 2537 * Grab a reference to a task's mm, if it is not already going away 2538 * and ptrace_may_access with the mode parameter passed to it 2539 * succeeds. 2540 */ 2541 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2542 /* Remove the current tasks stale references to the old mm_struct */ 2543 extern void mm_release(struct task_struct *, struct mm_struct *); 2544 2545 #ifdef CONFIG_HAVE_COPY_THREAD_TLS 2546 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, 2547 struct task_struct *, unsigned long); 2548 #else 2549 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2550 struct task_struct *); 2551 2552 /* Architectures that haven't opted into copy_thread_tls get the tls argument 2553 * via pt_regs, so ignore the tls argument passed via C. */ 2554 static inline int copy_thread_tls( 2555 unsigned long clone_flags, unsigned long sp, unsigned long arg, 2556 struct task_struct *p, unsigned long tls) 2557 { 2558 return copy_thread(clone_flags, sp, arg, p); 2559 } 2560 #endif 2561 extern void flush_thread(void); 2562 extern void exit_thread(void); 2563 2564 extern void exit_files(struct task_struct *); 2565 extern void __cleanup_sighand(struct sighand_struct *); 2566 2567 extern void exit_itimers(struct signal_struct *); 2568 extern void flush_itimer_signals(void); 2569 2570 extern void do_group_exit(int); 2571 2572 extern int do_execve(struct filename *, 2573 const char __user * const __user *, 2574 const char __user * const __user *); 2575 extern int do_execveat(int, struct filename *, 2576 const char __user * const __user *, 2577 const char __user * const __user *, 2578 int); 2579 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long); 2580 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2581 struct task_struct *fork_idle(int); 2582 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2583 2584 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 2585 static inline void set_task_comm(struct task_struct *tsk, const char *from) 2586 { 2587 __set_task_comm(tsk, from, false); 2588 } 2589 extern char *get_task_comm(char *to, struct task_struct *tsk); 2590 2591 #ifdef CONFIG_SMP 2592 void scheduler_ipi(void); 2593 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2594 #else 2595 static inline void scheduler_ipi(void) { } 2596 static inline unsigned long wait_task_inactive(struct task_struct *p, 2597 long match_state) 2598 { 2599 return 1; 2600 } 2601 #endif 2602 2603 #define tasklist_empty() \ 2604 list_empty(&init_task.tasks) 2605 2606 #define next_task(p) \ 2607 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2608 2609 #define for_each_process(p) \ 2610 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2611 2612 extern bool current_is_single_threaded(void); 2613 2614 /* 2615 * Careful: do_each_thread/while_each_thread is a double loop so 2616 * 'break' will not work as expected - use goto instead. 2617 */ 2618 #define do_each_thread(g, t) \ 2619 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2620 2621 #define while_each_thread(g, t) \ 2622 while ((t = next_thread(t)) != g) 2623 2624 #define __for_each_thread(signal, t) \ 2625 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) 2626 2627 #define for_each_thread(p, t) \ 2628 __for_each_thread((p)->signal, t) 2629 2630 /* Careful: this is a double loop, 'break' won't work as expected. */ 2631 #define for_each_process_thread(p, t) \ 2632 for_each_process(p) for_each_thread(p, t) 2633 2634 static inline int get_nr_threads(struct task_struct *tsk) 2635 { 2636 return tsk->signal->nr_threads; 2637 } 2638 2639 static inline bool thread_group_leader(struct task_struct *p) 2640 { 2641 return p->exit_signal >= 0; 2642 } 2643 2644 /* Do to the insanities of de_thread it is possible for a process 2645 * to have the pid of the thread group leader without actually being 2646 * the thread group leader. For iteration through the pids in proc 2647 * all we care about is that we have a task with the appropriate 2648 * pid, we don't actually care if we have the right task. 2649 */ 2650 static inline bool has_group_leader_pid(struct task_struct *p) 2651 { 2652 return task_pid(p) == p->signal->leader_pid; 2653 } 2654 2655 static inline 2656 bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 2657 { 2658 return p1->signal == p2->signal; 2659 } 2660 2661 static inline struct task_struct *next_thread(const struct task_struct *p) 2662 { 2663 return list_entry_rcu(p->thread_group.next, 2664 struct task_struct, thread_group); 2665 } 2666 2667 static inline int thread_group_empty(struct task_struct *p) 2668 { 2669 return list_empty(&p->thread_group); 2670 } 2671 2672 #define delay_group_leader(p) \ 2673 (thread_group_leader(p) && !thread_group_empty(p)) 2674 2675 /* 2676 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2677 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2678 * pins the final release of task.io_context. Also protects ->cpuset and 2679 * ->cgroup.subsys[]. And ->vfork_done. 2680 * 2681 * Nests both inside and outside of read_lock(&tasklist_lock). 2682 * It must not be nested with write_lock_irq(&tasklist_lock), 2683 * neither inside nor outside. 2684 */ 2685 static inline void task_lock(struct task_struct *p) 2686 { 2687 spin_lock(&p->alloc_lock); 2688 } 2689 2690 static inline void task_unlock(struct task_struct *p) 2691 { 2692 spin_unlock(&p->alloc_lock); 2693 } 2694 2695 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2696 unsigned long *flags); 2697 2698 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2699 unsigned long *flags) 2700 { 2701 struct sighand_struct *ret; 2702 2703 ret = __lock_task_sighand(tsk, flags); 2704 (void)__cond_lock(&tsk->sighand->siglock, ret); 2705 return ret; 2706 } 2707 2708 static inline void unlock_task_sighand(struct task_struct *tsk, 2709 unsigned long *flags) 2710 { 2711 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2712 } 2713 2714 /** 2715 * threadgroup_change_begin - mark the beginning of changes to a threadgroup 2716 * @tsk: task causing the changes 2717 * 2718 * All operations which modify a threadgroup - a new thread joining the 2719 * group, death of a member thread (the assertion of PF_EXITING) and 2720 * exec(2) dethreading the process and replacing the leader - are wrapped 2721 * by threadgroup_change_{begin|end}(). This is to provide a place which 2722 * subsystems needing threadgroup stability can hook into for 2723 * synchronization. 2724 */ 2725 static inline void threadgroup_change_begin(struct task_struct *tsk) 2726 { 2727 might_sleep(); 2728 cgroup_threadgroup_change_begin(tsk); 2729 } 2730 2731 /** 2732 * threadgroup_change_end - mark the end of changes to a threadgroup 2733 * @tsk: task causing the changes 2734 * 2735 * See threadgroup_change_begin(). 2736 */ 2737 static inline void threadgroup_change_end(struct task_struct *tsk) 2738 { 2739 cgroup_threadgroup_change_end(tsk); 2740 } 2741 2742 #ifndef __HAVE_THREAD_FUNCTIONS 2743 2744 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 2745 #define task_stack_page(task) ((task)->stack) 2746 2747 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2748 { 2749 *task_thread_info(p) = *task_thread_info(org); 2750 task_thread_info(p)->task = p; 2751 } 2752 2753 /* 2754 * Return the address of the last usable long on the stack. 2755 * 2756 * When the stack grows down, this is just above the thread 2757 * info struct. Going any lower will corrupt the threadinfo. 2758 * 2759 * When the stack grows up, this is the highest address. 2760 * Beyond that position, we corrupt data on the next page. 2761 */ 2762 static inline unsigned long *end_of_stack(struct task_struct *p) 2763 { 2764 #ifdef CONFIG_STACK_GROWSUP 2765 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1; 2766 #else 2767 return (unsigned long *)(task_thread_info(p) + 1); 2768 #endif 2769 } 2770 2771 #endif 2772 #define task_stack_end_corrupted(task) \ 2773 (*(end_of_stack(task)) != STACK_END_MAGIC) 2774 2775 static inline int object_is_on_stack(void *obj) 2776 { 2777 void *stack = task_stack_page(current); 2778 2779 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2780 } 2781 2782 extern void thread_info_cache_init(void); 2783 2784 #ifdef CONFIG_DEBUG_STACK_USAGE 2785 static inline unsigned long stack_not_used(struct task_struct *p) 2786 { 2787 unsigned long *n = end_of_stack(p); 2788 2789 do { /* Skip over canary */ 2790 n++; 2791 } while (!*n); 2792 2793 return (unsigned long)n - (unsigned long)end_of_stack(p); 2794 } 2795 #endif 2796 extern void set_task_stack_end_magic(struct task_struct *tsk); 2797 2798 /* set thread flags in other task's structures 2799 * - see asm/thread_info.h for TIF_xxxx flags available 2800 */ 2801 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2802 { 2803 set_ti_thread_flag(task_thread_info(tsk), flag); 2804 } 2805 2806 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2807 { 2808 clear_ti_thread_flag(task_thread_info(tsk), flag); 2809 } 2810 2811 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2812 { 2813 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2814 } 2815 2816 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2817 { 2818 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2819 } 2820 2821 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2822 { 2823 return test_ti_thread_flag(task_thread_info(tsk), flag); 2824 } 2825 2826 static inline void set_tsk_need_resched(struct task_struct *tsk) 2827 { 2828 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2829 } 2830 2831 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2832 { 2833 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2834 } 2835 2836 static inline int test_tsk_need_resched(struct task_struct *tsk) 2837 { 2838 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2839 } 2840 2841 static inline int restart_syscall(void) 2842 { 2843 set_tsk_thread_flag(current, TIF_SIGPENDING); 2844 return -ERESTARTNOINTR; 2845 } 2846 2847 static inline int signal_pending(struct task_struct *p) 2848 { 2849 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2850 } 2851 2852 static inline int __fatal_signal_pending(struct task_struct *p) 2853 { 2854 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2855 } 2856 2857 static inline int fatal_signal_pending(struct task_struct *p) 2858 { 2859 return signal_pending(p) && __fatal_signal_pending(p); 2860 } 2861 2862 static inline int signal_pending_state(long state, struct task_struct *p) 2863 { 2864 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2865 return 0; 2866 if (!signal_pending(p)) 2867 return 0; 2868 2869 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2870 } 2871 2872 /* 2873 * cond_resched() and cond_resched_lock(): latency reduction via 2874 * explicit rescheduling in places that are safe. The return 2875 * value indicates whether a reschedule was done in fact. 2876 * cond_resched_lock() will drop the spinlock before scheduling, 2877 * cond_resched_softirq() will enable bhs before scheduling. 2878 */ 2879 extern int _cond_resched(void); 2880 2881 #define cond_resched() ({ \ 2882 ___might_sleep(__FILE__, __LINE__, 0); \ 2883 _cond_resched(); \ 2884 }) 2885 2886 extern int __cond_resched_lock(spinlock_t *lock); 2887 2888 #ifdef CONFIG_PREEMPT_COUNT 2889 #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2890 #else 2891 #define PREEMPT_LOCK_OFFSET 0 2892 #endif 2893 2894 #define cond_resched_lock(lock) ({ \ 2895 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 2896 __cond_resched_lock(lock); \ 2897 }) 2898 2899 extern int __cond_resched_softirq(void); 2900 2901 #define cond_resched_softirq() ({ \ 2902 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2903 __cond_resched_softirq(); \ 2904 }) 2905 2906 static inline void cond_resched_rcu(void) 2907 { 2908 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 2909 rcu_read_unlock(); 2910 cond_resched(); 2911 rcu_read_lock(); 2912 #endif 2913 } 2914 2915 /* 2916 * Does a critical section need to be broken due to another 2917 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2918 * but a general need for low latency) 2919 */ 2920 static inline int spin_needbreak(spinlock_t *lock) 2921 { 2922 #ifdef CONFIG_PREEMPT 2923 return spin_is_contended(lock); 2924 #else 2925 return 0; 2926 #endif 2927 } 2928 2929 /* 2930 * Idle thread specific functions to determine the need_resched 2931 * polling state. 2932 */ 2933 #ifdef TIF_POLLING_NRFLAG 2934 static inline int tsk_is_polling(struct task_struct *p) 2935 { 2936 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 2937 } 2938 2939 static inline void __current_set_polling(void) 2940 { 2941 set_thread_flag(TIF_POLLING_NRFLAG); 2942 } 2943 2944 static inline bool __must_check current_set_polling_and_test(void) 2945 { 2946 __current_set_polling(); 2947 2948 /* 2949 * Polling state must be visible before we test NEED_RESCHED, 2950 * paired by resched_curr() 2951 */ 2952 smp_mb__after_atomic(); 2953 2954 return unlikely(tif_need_resched()); 2955 } 2956 2957 static inline void __current_clr_polling(void) 2958 { 2959 clear_thread_flag(TIF_POLLING_NRFLAG); 2960 } 2961 2962 static inline bool __must_check current_clr_polling_and_test(void) 2963 { 2964 __current_clr_polling(); 2965 2966 /* 2967 * Polling state must be visible before we test NEED_RESCHED, 2968 * paired by resched_curr() 2969 */ 2970 smp_mb__after_atomic(); 2971 2972 return unlikely(tif_need_resched()); 2973 } 2974 2975 #else 2976 static inline int tsk_is_polling(struct task_struct *p) { return 0; } 2977 static inline void __current_set_polling(void) { } 2978 static inline void __current_clr_polling(void) { } 2979 2980 static inline bool __must_check current_set_polling_and_test(void) 2981 { 2982 return unlikely(tif_need_resched()); 2983 } 2984 static inline bool __must_check current_clr_polling_and_test(void) 2985 { 2986 return unlikely(tif_need_resched()); 2987 } 2988 #endif 2989 2990 static inline void current_clr_polling(void) 2991 { 2992 __current_clr_polling(); 2993 2994 /* 2995 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit. 2996 * Once the bit is cleared, we'll get IPIs with every new 2997 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also 2998 * fold. 2999 */ 3000 smp_mb(); /* paired with resched_curr() */ 3001 3002 preempt_fold_need_resched(); 3003 } 3004 3005 static __always_inline bool need_resched(void) 3006 { 3007 return unlikely(tif_need_resched()); 3008 } 3009 3010 /* 3011 * Thread group CPU time accounting. 3012 */ 3013 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 3014 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 3015 3016 /* 3017 * Reevaluate whether the task has signals pending delivery. 3018 * Wake the task if so. 3019 * This is required every time the blocked sigset_t changes. 3020 * callers must hold sighand->siglock. 3021 */ 3022 extern void recalc_sigpending_and_wake(struct task_struct *t); 3023 extern void recalc_sigpending(void); 3024 3025 extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 3026 3027 static inline void signal_wake_up(struct task_struct *t, bool resume) 3028 { 3029 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 3030 } 3031 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 3032 { 3033 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 3034 } 3035 3036 /* 3037 * Wrappers for p->thread_info->cpu access. No-op on UP. 3038 */ 3039 #ifdef CONFIG_SMP 3040 3041 static inline unsigned int task_cpu(const struct task_struct *p) 3042 { 3043 return task_thread_info(p)->cpu; 3044 } 3045 3046 static inline int task_node(const struct task_struct *p) 3047 { 3048 return cpu_to_node(task_cpu(p)); 3049 } 3050 3051 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 3052 3053 #else 3054 3055 static inline unsigned int task_cpu(const struct task_struct *p) 3056 { 3057 return 0; 3058 } 3059 3060 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 3061 { 3062 } 3063 3064 #endif /* CONFIG_SMP */ 3065 3066 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 3067 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 3068 3069 #ifdef CONFIG_CGROUP_SCHED 3070 extern struct task_group root_task_group; 3071 #endif /* CONFIG_CGROUP_SCHED */ 3072 3073 extern int task_can_switch_user(struct user_struct *up, 3074 struct task_struct *tsk); 3075 3076 #ifdef CONFIG_TASK_XACCT 3077 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3078 { 3079 tsk->ioac.rchar += amt; 3080 } 3081 3082 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3083 { 3084 tsk->ioac.wchar += amt; 3085 } 3086 3087 static inline void inc_syscr(struct task_struct *tsk) 3088 { 3089 tsk->ioac.syscr++; 3090 } 3091 3092 static inline void inc_syscw(struct task_struct *tsk) 3093 { 3094 tsk->ioac.syscw++; 3095 } 3096 #else 3097 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3098 { 3099 } 3100 3101 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3102 { 3103 } 3104 3105 static inline void inc_syscr(struct task_struct *tsk) 3106 { 3107 } 3108 3109 static inline void inc_syscw(struct task_struct *tsk) 3110 { 3111 } 3112 #endif 3113 3114 #ifndef TASK_SIZE_OF 3115 #define TASK_SIZE_OF(tsk) TASK_SIZE 3116 #endif 3117 3118 #ifdef CONFIG_MEMCG 3119 extern void mm_update_next_owner(struct mm_struct *mm); 3120 #else 3121 static inline void mm_update_next_owner(struct mm_struct *mm) 3122 { 3123 } 3124 #endif /* CONFIG_MEMCG */ 3125 3126 static inline unsigned long task_rlimit(const struct task_struct *tsk, 3127 unsigned int limit) 3128 { 3129 return READ_ONCE(tsk->signal->rlim[limit].rlim_cur); 3130 } 3131 3132 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 3133 unsigned int limit) 3134 { 3135 return READ_ONCE(tsk->signal->rlim[limit].rlim_max); 3136 } 3137 3138 static inline unsigned long rlimit(unsigned int limit) 3139 { 3140 return task_rlimit(current, limit); 3141 } 3142 3143 static inline unsigned long rlimit_max(unsigned int limit) 3144 { 3145 return task_rlimit_max(current, limit); 3146 } 3147 3148 #endif 3149