1 #ifndef _LINUX_SCHED_H 2 #define _LINUX_SCHED_H 3 4 #include <uapi/linux/sched.h> 5 6 7 struct sched_param { 8 int sched_priority; 9 }; 10 11 #include <asm/param.h> /* for HZ */ 12 13 #include <linux/capability.h> 14 #include <linux/threads.h> 15 #include <linux/kernel.h> 16 #include <linux/types.h> 17 #include <linux/timex.h> 18 #include <linux/jiffies.h> 19 #include <linux/rbtree.h> 20 #include <linux/thread_info.h> 21 #include <linux/cpumask.h> 22 #include <linux/errno.h> 23 #include <linux/nodemask.h> 24 #include <linux/mm_types.h> 25 #include <linux/preempt_mask.h> 26 27 #include <asm/page.h> 28 #include <asm/ptrace.h> 29 #include <asm/cputime.h> 30 31 #include <linux/smp.h> 32 #include <linux/sem.h> 33 #include <linux/signal.h> 34 #include <linux/compiler.h> 35 #include <linux/completion.h> 36 #include <linux/pid.h> 37 #include <linux/percpu.h> 38 #include <linux/topology.h> 39 #include <linux/proportions.h> 40 #include <linux/seccomp.h> 41 #include <linux/rcupdate.h> 42 #include <linux/rculist.h> 43 #include <linux/rtmutex.h> 44 45 #include <linux/time.h> 46 #include <linux/param.h> 47 #include <linux/resource.h> 48 #include <linux/timer.h> 49 #include <linux/hrtimer.h> 50 #include <linux/task_io_accounting.h> 51 #include <linux/latencytop.h> 52 #include <linux/cred.h> 53 #include <linux/llist.h> 54 #include <linux/uidgid.h> 55 #include <linux/gfp.h> 56 57 #include <asm/processor.h> 58 59 struct exec_domain; 60 struct futex_pi_state; 61 struct robust_list_head; 62 struct bio_list; 63 struct fs_struct; 64 struct perf_event_context; 65 struct blk_plug; 66 67 /* 68 * List of flags we want to share for kernel threads, 69 * if only because they are not used by them anyway. 70 */ 71 #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND) 72 73 /* 74 * These are the constant used to fake the fixed-point load-average 75 * counting. Some notes: 76 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 77 * a load-average precision of 10 bits integer + 11 bits fractional 78 * - if you want to count load-averages more often, you need more 79 * precision, or rounding will get you. With 2-second counting freq, 80 * the EXP_n values would be 1981, 2034 and 2043 if still using only 81 * 11 bit fractions. 82 */ 83 extern unsigned long avenrun[]; /* Load averages */ 84 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 85 86 #define FSHIFT 11 /* nr of bits of precision */ 87 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 88 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 89 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 90 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 91 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 92 93 #define CALC_LOAD(load,exp,n) \ 94 load *= exp; \ 95 load += n*(FIXED_1-exp); \ 96 load >>= FSHIFT; 97 98 extern unsigned long total_forks; 99 extern int nr_threads; 100 DECLARE_PER_CPU(unsigned long, process_counts); 101 extern int nr_processes(void); 102 extern unsigned long nr_running(void); 103 extern unsigned long nr_iowait(void); 104 extern unsigned long nr_iowait_cpu(int cpu); 105 extern unsigned long this_cpu_load(void); 106 107 108 extern void calc_global_load(unsigned long ticks); 109 extern void update_cpu_load_nohz(void); 110 111 extern unsigned long get_parent_ip(unsigned long addr); 112 113 extern void dump_cpu_task(int cpu); 114 115 struct seq_file; 116 struct cfs_rq; 117 struct task_group; 118 #ifdef CONFIG_SCHED_DEBUG 119 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 120 extern void proc_sched_set_task(struct task_struct *p); 121 extern void 122 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 123 #endif 124 125 /* 126 * Task state bitmask. NOTE! These bits are also 127 * encoded in fs/proc/array.c: get_task_state(). 128 * 129 * We have two separate sets of flags: task->state 130 * is about runnability, while task->exit_state are 131 * about the task exiting. Confusing, but this way 132 * modifying one set can't modify the other one by 133 * mistake. 134 */ 135 #define TASK_RUNNING 0 136 #define TASK_INTERRUPTIBLE 1 137 #define TASK_UNINTERRUPTIBLE 2 138 #define __TASK_STOPPED 4 139 #define __TASK_TRACED 8 140 /* in tsk->exit_state */ 141 #define EXIT_ZOMBIE 16 142 #define EXIT_DEAD 32 143 /* in tsk->state again */ 144 #define TASK_DEAD 64 145 #define TASK_WAKEKILL 128 146 #define TASK_WAKING 256 147 #define TASK_PARKED 512 148 #define TASK_STATE_MAX 1024 149 150 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKWP" 151 152 extern char ___assert_task_state[1 - 2*!!( 153 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 154 155 /* Convenience macros for the sake of set_task_state */ 156 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 157 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 158 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 159 160 /* Convenience macros for the sake of wake_up */ 161 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 162 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 163 164 /* get_task_state() */ 165 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 166 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 167 __TASK_TRACED) 168 169 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 170 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 171 #define task_is_dead(task) ((task)->exit_state != 0) 172 #define task_is_stopped_or_traced(task) \ 173 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 174 #define task_contributes_to_load(task) \ 175 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 176 (task->flags & PF_FROZEN) == 0) 177 178 #define __set_task_state(tsk, state_value) \ 179 do { (tsk)->state = (state_value); } while (0) 180 #define set_task_state(tsk, state_value) \ 181 set_mb((tsk)->state, (state_value)) 182 183 /* 184 * set_current_state() includes a barrier so that the write of current->state 185 * is correctly serialised wrt the caller's subsequent test of whether to 186 * actually sleep: 187 * 188 * set_current_state(TASK_UNINTERRUPTIBLE); 189 * if (do_i_need_to_sleep()) 190 * schedule(); 191 * 192 * If the caller does not need such serialisation then use __set_current_state() 193 */ 194 #define __set_current_state(state_value) \ 195 do { current->state = (state_value); } while (0) 196 #define set_current_state(state_value) \ 197 set_mb(current->state, (state_value)) 198 199 /* Task command name length */ 200 #define TASK_COMM_LEN 16 201 202 #include <linux/spinlock.h> 203 204 /* 205 * This serializes "schedule()" and also protects 206 * the run-queue from deletions/modifications (but 207 * _adding_ to the beginning of the run-queue has 208 * a separate lock). 209 */ 210 extern rwlock_t tasklist_lock; 211 extern spinlock_t mmlist_lock; 212 213 struct task_struct; 214 215 #ifdef CONFIG_PROVE_RCU 216 extern int lockdep_tasklist_lock_is_held(void); 217 #endif /* #ifdef CONFIG_PROVE_RCU */ 218 219 extern void sched_init(void); 220 extern void sched_init_smp(void); 221 extern asmlinkage void schedule_tail(struct task_struct *prev); 222 extern void init_idle(struct task_struct *idle, int cpu); 223 extern void init_idle_bootup_task(struct task_struct *idle); 224 225 extern int runqueue_is_locked(int cpu); 226 227 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 228 extern void nohz_balance_enter_idle(int cpu); 229 extern void set_cpu_sd_state_idle(void); 230 extern int get_nohz_timer_target(void); 231 #else 232 static inline void nohz_balance_enter_idle(int cpu) { } 233 static inline void set_cpu_sd_state_idle(void) { } 234 #endif 235 236 /* 237 * Only dump TASK_* tasks. (0 for all tasks) 238 */ 239 extern void show_state_filter(unsigned long state_filter); 240 241 static inline void show_state(void) 242 { 243 show_state_filter(0); 244 } 245 246 extern void show_regs(struct pt_regs *); 247 248 /* 249 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 250 * task), SP is the stack pointer of the first frame that should be shown in the back 251 * trace (or NULL if the entire call-chain of the task should be shown). 252 */ 253 extern void show_stack(struct task_struct *task, unsigned long *sp); 254 255 void io_schedule(void); 256 long io_schedule_timeout(long timeout); 257 258 extern void cpu_init (void); 259 extern void trap_init(void); 260 extern void update_process_times(int user); 261 extern void scheduler_tick(void); 262 263 extern void sched_show_task(struct task_struct *p); 264 265 #ifdef CONFIG_LOCKUP_DETECTOR 266 extern void touch_softlockup_watchdog(void); 267 extern void touch_softlockup_watchdog_sync(void); 268 extern void touch_all_softlockup_watchdogs(void); 269 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 270 void __user *buffer, 271 size_t *lenp, loff_t *ppos); 272 extern unsigned int softlockup_panic; 273 void lockup_detector_init(void); 274 #else 275 static inline void touch_softlockup_watchdog(void) 276 { 277 } 278 static inline void touch_softlockup_watchdog_sync(void) 279 { 280 } 281 static inline void touch_all_softlockup_watchdogs(void) 282 { 283 } 284 static inline void lockup_detector_init(void) 285 { 286 } 287 #endif 288 289 #ifdef CONFIG_DETECT_HUNG_TASK 290 void reset_hung_task_detector(void); 291 #else 292 static inline void reset_hung_task_detector(void) 293 { 294 } 295 #endif 296 297 /* Attach to any functions which should be ignored in wchan output. */ 298 #define __sched __attribute__((__section__(".sched.text"))) 299 300 /* Linker adds these: start and end of __sched functions */ 301 extern char __sched_text_start[], __sched_text_end[]; 302 303 /* Is this address in the __sched functions? */ 304 extern int in_sched_functions(unsigned long addr); 305 306 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 307 extern signed long schedule_timeout(signed long timeout); 308 extern signed long schedule_timeout_interruptible(signed long timeout); 309 extern signed long schedule_timeout_killable(signed long timeout); 310 extern signed long schedule_timeout_uninterruptible(signed long timeout); 311 asmlinkage void schedule(void); 312 extern void schedule_preempt_disabled(void); 313 314 struct nsproxy; 315 struct user_namespace; 316 317 #ifdef CONFIG_MMU 318 extern void arch_pick_mmap_layout(struct mm_struct *mm); 319 extern unsigned long 320 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 321 unsigned long, unsigned long); 322 extern unsigned long 323 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 324 unsigned long len, unsigned long pgoff, 325 unsigned long flags); 326 #else 327 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 328 #endif 329 330 331 extern void set_dumpable(struct mm_struct *mm, int value); 332 extern int get_dumpable(struct mm_struct *mm); 333 334 #define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 335 #define SUID_DUMP_USER 1 /* Dump as user of process */ 336 #define SUID_DUMP_ROOT 2 /* Dump as root */ 337 338 /* mm flags */ 339 /* dumpable bits */ 340 #define MMF_DUMPABLE 0 /* core dump is permitted */ 341 #define MMF_DUMP_SECURELY 1 /* core file is readable only by root */ 342 343 #define MMF_DUMPABLE_BITS 2 344 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 345 346 /* coredump filter bits */ 347 #define MMF_DUMP_ANON_PRIVATE 2 348 #define MMF_DUMP_ANON_SHARED 3 349 #define MMF_DUMP_MAPPED_PRIVATE 4 350 #define MMF_DUMP_MAPPED_SHARED 5 351 #define MMF_DUMP_ELF_HEADERS 6 352 #define MMF_DUMP_HUGETLB_PRIVATE 7 353 #define MMF_DUMP_HUGETLB_SHARED 8 354 355 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 356 #define MMF_DUMP_FILTER_BITS 7 357 #define MMF_DUMP_FILTER_MASK \ 358 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 359 #define MMF_DUMP_FILTER_DEFAULT \ 360 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 361 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 362 363 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 364 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 365 #else 366 # define MMF_DUMP_MASK_DEFAULT_ELF 0 367 #endif 368 /* leave room for more dump flags */ 369 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 370 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 371 #define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 372 373 #define MMF_HAS_UPROBES 19 /* has uprobes */ 374 #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 375 376 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 377 378 struct sighand_struct { 379 atomic_t count; 380 struct k_sigaction action[_NSIG]; 381 spinlock_t siglock; 382 wait_queue_head_t signalfd_wqh; 383 }; 384 385 struct pacct_struct { 386 int ac_flag; 387 long ac_exitcode; 388 unsigned long ac_mem; 389 cputime_t ac_utime, ac_stime; 390 unsigned long ac_minflt, ac_majflt; 391 }; 392 393 struct cpu_itimer { 394 cputime_t expires; 395 cputime_t incr; 396 u32 error; 397 u32 incr_error; 398 }; 399 400 /** 401 * struct cputime - snaphsot of system and user cputime 402 * @utime: time spent in user mode 403 * @stime: time spent in system mode 404 * 405 * Gathers a generic snapshot of user and system time. 406 */ 407 struct cputime { 408 cputime_t utime; 409 cputime_t stime; 410 }; 411 412 /** 413 * struct task_cputime - collected CPU time counts 414 * @utime: time spent in user mode, in &cputime_t units 415 * @stime: time spent in kernel mode, in &cputime_t units 416 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 417 * 418 * This is an extension of struct cputime that includes the total runtime 419 * spent by the task from the scheduler point of view. 420 * 421 * As a result, this structure groups together three kinds of CPU time 422 * that are tracked for threads and thread groups. Most things considering 423 * CPU time want to group these counts together and treat all three 424 * of them in parallel. 425 */ 426 struct task_cputime { 427 cputime_t utime; 428 cputime_t stime; 429 unsigned long long sum_exec_runtime; 430 }; 431 /* Alternate field names when used to cache expirations. */ 432 #define prof_exp stime 433 #define virt_exp utime 434 #define sched_exp sum_exec_runtime 435 436 #define INIT_CPUTIME \ 437 (struct task_cputime) { \ 438 .utime = 0, \ 439 .stime = 0, \ 440 .sum_exec_runtime = 0, \ 441 } 442 443 #ifdef CONFIG_PREEMPT_COUNT 444 #define PREEMPT_DISABLED (1 + PREEMPT_ENABLED) 445 #else 446 #define PREEMPT_DISABLED PREEMPT_ENABLED 447 #endif 448 449 /* 450 * Disable preemption until the scheduler is running. 451 * Reset by start_kernel()->sched_init()->init_idle(). 452 * 453 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 454 * before the scheduler is active -- see should_resched(). 455 */ 456 #define INIT_PREEMPT_COUNT (PREEMPT_DISABLED + PREEMPT_ACTIVE) 457 458 /** 459 * struct thread_group_cputimer - thread group interval timer counts 460 * @cputime: thread group interval timers. 461 * @running: non-zero when there are timers running and 462 * @cputime receives updates. 463 * @lock: lock for fields in this struct. 464 * 465 * This structure contains the version of task_cputime, above, that is 466 * used for thread group CPU timer calculations. 467 */ 468 struct thread_group_cputimer { 469 struct task_cputime cputime; 470 int running; 471 raw_spinlock_t lock; 472 }; 473 474 #include <linux/rwsem.h> 475 struct autogroup; 476 477 /* 478 * NOTE! "signal_struct" does not have its own 479 * locking, because a shared signal_struct always 480 * implies a shared sighand_struct, so locking 481 * sighand_struct is always a proper superset of 482 * the locking of signal_struct. 483 */ 484 struct signal_struct { 485 atomic_t sigcnt; 486 atomic_t live; 487 int nr_threads; 488 489 wait_queue_head_t wait_chldexit; /* for wait4() */ 490 491 /* current thread group signal load-balancing target: */ 492 struct task_struct *curr_target; 493 494 /* shared signal handling: */ 495 struct sigpending shared_pending; 496 497 /* thread group exit support */ 498 int group_exit_code; 499 /* overloaded: 500 * - notify group_exit_task when ->count is equal to notify_count 501 * - everyone except group_exit_task is stopped during signal delivery 502 * of fatal signals, group_exit_task processes the signal. 503 */ 504 int notify_count; 505 struct task_struct *group_exit_task; 506 507 /* thread group stop support, overloads group_exit_code too */ 508 int group_stop_count; 509 unsigned int flags; /* see SIGNAL_* flags below */ 510 511 /* 512 * PR_SET_CHILD_SUBREAPER marks a process, like a service 513 * manager, to re-parent orphan (double-forking) child processes 514 * to this process instead of 'init'. The service manager is 515 * able to receive SIGCHLD signals and is able to investigate 516 * the process until it calls wait(). All children of this 517 * process will inherit a flag if they should look for a 518 * child_subreaper process at exit. 519 */ 520 unsigned int is_child_subreaper:1; 521 unsigned int has_child_subreaper:1; 522 523 /* POSIX.1b Interval Timers */ 524 int posix_timer_id; 525 struct list_head posix_timers; 526 527 /* ITIMER_REAL timer for the process */ 528 struct hrtimer real_timer; 529 struct pid *leader_pid; 530 ktime_t it_real_incr; 531 532 /* 533 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 534 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 535 * values are defined to 0 and 1 respectively 536 */ 537 struct cpu_itimer it[2]; 538 539 /* 540 * Thread group totals for process CPU timers. 541 * See thread_group_cputimer(), et al, for details. 542 */ 543 struct thread_group_cputimer cputimer; 544 545 /* Earliest-expiration cache. */ 546 struct task_cputime cputime_expires; 547 548 struct list_head cpu_timers[3]; 549 550 struct pid *tty_old_pgrp; 551 552 /* boolean value for session group leader */ 553 int leader; 554 555 struct tty_struct *tty; /* NULL if no tty */ 556 557 #ifdef CONFIG_SCHED_AUTOGROUP 558 struct autogroup *autogroup; 559 #endif 560 /* 561 * Cumulative resource counters for dead threads in the group, 562 * and for reaped dead child processes forked by this group. 563 * Live threads maintain their own counters and add to these 564 * in __exit_signal, except for the group leader. 565 */ 566 cputime_t utime, stime, cutime, cstime; 567 cputime_t gtime; 568 cputime_t cgtime; 569 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 570 struct cputime prev_cputime; 571 #endif 572 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 573 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 574 unsigned long inblock, oublock, cinblock, coublock; 575 unsigned long maxrss, cmaxrss; 576 struct task_io_accounting ioac; 577 578 /* 579 * Cumulative ns of schedule CPU time fo dead threads in the 580 * group, not including a zombie group leader, (This only differs 581 * from jiffies_to_ns(utime + stime) if sched_clock uses something 582 * other than jiffies.) 583 */ 584 unsigned long long sum_sched_runtime; 585 586 /* 587 * We don't bother to synchronize most readers of this at all, 588 * because there is no reader checking a limit that actually needs 589 * to get both rlim_cur and rlim_max atomically, and either one 590 * alone is a single word that can safely be read normally. 591 * getrlimit/setrlimit use task_lock(current->group_leader) to 592 * protect this instead of the siglock, because they really 593 * have no need to disable irqs. 594 */ 595 struct rlimit rlim[RLIM_NLIMITS]; 596 597 #ifdef CONFIG_BSD_PROCESS_ACCT 598 struct pacct_struct pacct; /* per-process accounting information */ 599 #endif 600 #ifdef CONFIG_TASKSTATS 601 struct taskstats *stats; 602 #endif 603 #ifdef CONFIG_AUDIT 604 unsigned audit_tty; 605 unsigned audit_tty_log_passwd; 606 struct tty_audit_buf *tty_audit_buf; 607 #endif 608 #ifdef CONFIG_CGROUPS 609 /* 610 * group_rwsem prevents new tasks from entering the threadgroup and 611 * member tasks from exiting,a more specifically, setting of 612 * PF_EXITING. fork and exit paths are protected with this rwsem 613 * using threadgroup_change_begin/end(). Users which require 614 * threadgroup to remain stable should use threadgroup_[un]lock() 615 * which also takes care of exec path. Currently, cgroup is the 616 * only user. 617 */ 618 struct rw_semaphore group_rwsem; 619 #endif 620 621 oom_flags_t oom_flags; 622 short oom_score_adj; /* OOM kill score adjustment */ 623 short oom_score_adj_min; /* OOM kill score adjustment min value. 624 * Only settable by CAP_SYS_RESOURCE. */ 625 626 struct mutex cred_guard_mutex; /* guard against foreign influences on 627 * credential calculations 628 * (notably. ptrace) */ 629 }; 630 631 /* 632 * Bits in flags field of signal_struct. 633 */ 634 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 635 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 636 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 637 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 638 /* 639 * Pending notifications to parent. 640 */ 641 #define SIGNAL_CLD_STOPPED 0x00000010 642 #define SIGNAL_CLD_CONTINUED 0x00000020 643 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 644 645 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 646 647 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 648 static inline int signal_group_exit(const struct signal_struct *sig) 649 { 650 return (sig->flags & SIGNAL_GROUP_EXIT) || 651 (sig->group_exit_task != NULL); 652 } 653 654 /* 655 * Some day this will be a full-fledged user tracking system.. 656 */ 657 struct user_struct { 658 atomic_t __count; /* reference count */ 659 atomic_t processes; /* How many processes does this user have? */ 660 atomic_t files; /* How many open files does this user have? */ 661 atomic_t sigpending; /* How many pending signals does this user have? */ 662 #ifdef CONFIG_INOTIFY_USER 663 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 664 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 665 #endif 666 #ifdef CONFIG_FANOTIFY 667 atomic_t fanotify_listeners; 668 #endif 669 #ifdef CONFIG_EPOLL 670 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 671 #endif 672 #ifdef CONFIG_POSIX_MQUEUE 673 /* protected by mq_lock */ 674 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 675 #endif 676 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 677 678 #ifdef CONFIG_KEYS 679 struct key *uid_keyring; /* UID specific keyring */ 680 struct key *session_keyring; /* UID's default session keyring */ 681 #endif 682 683 /* Hash table maintenance information */ 684 struct hlist_node uidhash_node; 685 kuid_t uid; 686 687 #ifdef CONFIG_PERF_EVENTS 688 atomic_long_t locked_vm; 689 #endif 690 }; 691 692 extern int uids_sysfs_init(void); 693 694 extern struct user_struct *find_user(kuid_t); 695 696 extern struct user_struct root_user; 697 #define INIT_USER (&root_user) 698 699 700 struct backing_dev_info; 701 struct reclaim_state; 702 703 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 704 struct sched_info { 705 /* cumulative counters */ 706 unsigned long pcount; /* # of times run on this cpu */ 707 unsigned long long run_delay; /* time spent waiting on a runqueue */ 708 709 /* timestamps */ 710 unsigned long long last_arrival,/* when we last ran on a cpu */ 711 last_queued; /* when we were last queued to run */ 712 }; 713 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ 714 715 #ifdef CONFIG_TASK_DELAY_ACCT 716 struct task_delay_info { 717 spinlock_t lock; 718 unsigned int flags; /* Private per-task flags */ 719 720 /* For each stat XXX, add following, aligned appropriately 721 * 722 * struct timespec XXX_start, XXX_end; 723 * u64 XXX_delay; 724 * u32 XXX_count; 725 * 726 * Atomicity of updates to XXX_delay, XXX_count protected by 727 * single lock above (split into XXX_lock if contention is an issue). 728 */ 729 730 /* 731 * XXX_count is incremented on every XXX operation, the delay 732 * associated with the operation is added to XXX_delay. 733 * XXX_delay contains the accumulated delay time in nanoseconds. 734 */ 735 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ 736 u64 blkio_delay; /* wait for sync block io completion */ 737 u64 swapin_delay; /* wait for swapin block io completion */ 738 u32 blkio_count; /* total count of the number of sync block */ 739 /* io operations performed */ 740 u32 swapin_count; /* total count of the number of swapin block */ 741 /* io operations performed */ 742 743 struct timespec freepages_start, freepages_end; 744 u64 freepages_delay; /* wait for memory reclaim */ 745 u32 freepages_count; /* total count of memory reclaim */ 746 }; 747 #endif /* CONFIG_TASK_DELAY_ACCT */ 748 749 static inline int sched_info_on(void) 750 { 751 #ifdef CONFIG_SCHEDSTATS 752 return 1; 753 #elif defined(CONFIG_TASK_DELAY_ACCT) 754 extern int delayacct_on; 755 return delayacct_on; 756 #else 757 return 0; 758 #endif 759 } 760 761 enum cpu_idle_type { 762 CPU_IDLE, 763 CPU_NOT_IDLE, 764 CPU_NEWLY_IDLE, 765 CPU_MAX_IDLE_TYPES 766 }; 767 768 /* 769 * Increase resolution of cpu_power calculations 770 */ 771 #define SCHED_POWER_SHIFT 10 772 #define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT) 773 774 /* 775 * sched-domains (multiprocessor balancing) declarations: 776 */ 777 #ifdef CONFIG_SMP 778 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 779 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 780 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 781 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 782 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 783 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 784 #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ 785 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 786 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 787 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 788 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 789 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 790 #define SD_NUMA 0x4000 /* cross-node balancing */ 791 792 extern int __weak arch_sd_sibiling_asym_packing(void); 793 794 struct sched_domain_attr { 795 int relax_domain_level; 796 }; 797 798 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 799 .relax_domain_level = -1, \ 800 } 801 802 extern int sched_domain_level_max; 803 804 struct sched_group; 805 806 struct sched_domain { 807 /* These fields must be setup */ 808 struct sched_domain *parent; /* top domain must be null terminated */ 809 struct sched_domain *child; /* bottom domain must be null terminated */ 810 struct sched_group *groups; /* the balancing groups of the domain */ 811 unsigned long min_interval; /* Minimum balance interval ms */ 812 unsigned long max_interval; /* Maximum balance interval ms */ 813 unsigned int busy_factor; /* less balancing by factor if busy */ 814 unsigned int imbalance_pct; /* No balance until over watermark */ 815 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 816 unsigned int busy_idx; 817 unsigned int idle_idx; 818 unsigned int newidle_idx; 819 unsigned int wake_idx; 820 unsigned int forkexec_idx; 821 unsigned int smt_gain; 822 823 int nohz_idle; /* NOHZ IDLE status */ 824 int flags; /* See SD_* */ 825 int level; 826 827 /* Runtime fields. */ 828 unsigned long last_balance; /* init to jiffies. units in jiffies */ 829 unsigned int balance_interval; /* initialise to 1. units in ms. */ 830 unsigned int nr_balance_failed; /* initialise to 0 */ 831 832 /* idle_balance() stats */ 833 u64 max_newidle_lb_cost; 834 unsigned long next_decay_max_lb_cost; 835 836 #ifdef CONFIG_SCHEDSTATS 837 /* load_balance() stats */ 838 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 839 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 840 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 841 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 842 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 843 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 844 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 845 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 846 847 /* Active load balancing */ 848 unsigned int alb_count; 849 unsigned int alb_failed; 850 unsigned int alb_pushed; 851 852 /* SD_BALANCE_EXEC stats */ 853 unsigned int sbe_count; 854 unsigned int sbe_balanced; 855 unsigned int sbe_pushed; 856 857 /* SD_BALANCE_FORK stats */ 858 unsigned int sbf_count; 859 unsigned int sbf_balanced; 860 unsigned int sbf_pushed; 861 862 /* try_to_wake_up() stats */ 863 unsigned int ttwu_wake_remote; 864 unsigned int ttwu_move_affine; 865 unsigned int ttwu_move_balance; 866 #endif 867 #ifdef CONFIG_SCHED_DEBUG 868 char *name; 869 #endif 870 union { 871 void *private; /* used during construction */ 872 struct rcu_head rcu; /* used during destruction */ 873 }; 874 875 unsigned int span_weight; 876 /* 877 * Span of all CPUs in this domain. 878 * 879 * NOTE: this field is variable length. (Allocated dynamically 880 * by attaching extra space to the end of the structure, 881 * depending on how many CPUs the kernel has booted up with) 882 */ 883 unsigned long span[0]; 884 }; 885 886 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 887 { 888 return to_cpumask(sd->span); 889 } 890 891 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 892 struct sched_domain_attr *dattr_new); 893 894 /* Allocate an array of sched domains, for partition_sched_domains(). */ 895 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 896 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 897 898 bool cpus_share_cache(int this_cpu, int that_cpu); 899 900 #else /* CONFIG_SMP */ 901 902 struct sched_domain_attr; 903 904 static inline void 905 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 906 struct sched_domain_attr *dattr_new) 907 { 908 } 909 910 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 911 { 912 return true; 913 } 914 915 #endif /* !CONFIG_SMP */ 916 917 918 struct io_context; /* See blkdev.h */ 919 920 921 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 922 extern void prefetch_stack(struct task_struct *t); 923 #else 924 static inline void prefetch_stack(struct task_struct *t) { } 925 #endif 926 927 struct audit_context; /* See audit.c */ 928 struct mempolicy; 929 struct pipe_inode_info; 930 struct uts_namespace; 931 932 struct load_weight { 933 unsigned long weight; 934 u32 inv_weight; 935 }; 936 937 struct sched_avg { 938 /* 939 * These sums represent an infinite geometric series and so are bound 940 * above by 1024/(1-y). Thus we only need a u32 to store them for all 941 * choices of y < 1-2^(-32)*1024. 942 */ 943 u32 runnable_avg_sum, runnable_avg_period; 944 u64 last_runnable_update; 945 s64 decay_count; 946 unsigned long load_avg_contrib; 947 }; 948 949 #ifdef CONFIG_SCHEDSTATS 950 struct sched_statistics { 951 u64 wait_start; 952 u64 wait_max; 953 u64 wait_count; 954 u64 wait_sum; 955 u64 iowait_count; 956 u64 iowait_sum; 957 958 u64 sleep_start; 959 u64 sleep_max; 960 s64 sum_sleep_runtime; 961 962 u64 block_start; 963 u64 block_max; 964 u64 exec_max; 965 u64 slice_max; 966 967 u64 nr_migrations_cold; 968 u64 nr_failed_migrations_affine; 969 u64 nr_failed_migrations_running; 970 u64 nr_failed_migrations_hot; 971 u64 nr_forced_migrations; 972 973 u64 nr_wakeups; 974 u64 nr_wakeups_sync; 975 u64 nr_wakeups_migrate; 976 u64 nr_wakeups_local; 977 u64 nr_wakeups_remote; 978 u64 nr_wakeups_affine; 979 u64 nr_wakeups_affine_attempts; 980 u64 nr_wakeups_passive; 981 u64 nr_wakeups_idle; 982 }; 983 #endif 984 985 struct sched_entity { 986 struct load_weight load; /* for load-balancing */ 987 struct rb_node run_node; 988 struct list_head group_node; 989 unsigned int on_rq; 990 991 u64 exec_start; 992 u64 sum_exec_runtime; 993 u64 vruntime; 994 u64 prev_sum_exec_runtime; 995 996 u64 nr_migrations; 997 998 #ifdef CONFIG_SCHEDSTATS 999 struct sched_statistics statistics; 1000 #endif 1001 1002 #ifdef CONFIG_FAIR_GROUP_SCHED 1003 struct sched_entity *parent; 1004 /* rq on which this entity is (to be) queued: */ 1005 struct cfs_rq *cfs_rq; 1006 /* rq "owned" by this entity/group: */ 1007 struct cfs_rq *my_q; 1008 #endif 1009 1010 #ifdef CONFIG_SMP 1011 /* Per-entity load-tracking */ 1012 struct sched_avg avg; 1013 #endif 1014 }; 1015 1016 struct sched_rt_entity { 1017 struct list_head run_list; 1018 unsigned long timeout; 1019 unsigned long watchdog_stamp; 1020 unsigned int time_slice; 1021 1022 struct sched_rt_entity *back; 1023 #ifdef CONFIG_RT_GROUP_SCHED 1024 struct sched_rt_entity *parent; 1025 /* rq on which this entity is (to be) queued: */ 1026 struct rt_rq *rt_rq; 1027 /* rq "owned" by this entity/group: */ 1028 struct rt_rq *my_q; 1029 #endif 1030 }; 1031 1032 1033 struct rcu_node; 1034 1035 enum perf_event_task_context { 1036 perf_invalid_context = -1, 1037 perf_hw_context = 0, 1038 perf_sw_context, 1039 perf_nr_task_contexts, 1040 }; 1041 1042 struct task_struct { 1043 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1044 void *stack; 1045 atomic_t usage; 1046 unsigned int flags; /* per process flags, defined below */ 1047 unsigned int ptrace; 1048 1049 #ifdef CONFIG_SMP 1050 struct llist_node wake_entry; 1051 int on_cpu; 1052 struct task_struct *last_wakee; 1053 unsigned long wakee_flips; 1054 unsigned long wakee_flip_decay_ts; 1055 1056 int wake_cpu; 1057 #endif 1058 int on_rq; 1059 1060 int prio, static_prio, normal_prio; 1061 unsigned int rt_priority; 1062 const struct sched_class *sched_class; 1063 struct sched_entity se; 1064 struct sched_rt_entity rt; 1065 #ifdef CONFIG_CGROUP_SCHED 1066 struct task_group *sched_task_group; 1067 #endif 1068 1069 #ifdef CONFIG_PREEMPT_NOTIFIERS 1070 /* list of struct preempt_notifier: */ 1071 struct hlist_head preempt_notifiers; 1072 #endif 1073 1074 #ifdef CONFIG_BLK_DEV_IO_TRACE 1075 unsigned int btrace_seq; 1076 #endif 1077 1078 unsigned int policy; 1079 int nr_cpus_allowed; 1080 cpumask_t cpus_allowed; 1081 1082 #ifdef CONFIG_PREEMPT_RCU 1083 int rcu_read_lock_nesting; 1084 char rcu_read_unlock_special; 1085 struct list_head rcu_node_entry; 1086 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1087 #ifdef CONFIG_TREE_PREEMPT_RCU 1088 struct rcu_node *rcu_blocked_node; 1089 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1090 #ifdef CONFIG_RCU_BOOST 1091 struct rt_mutex *rcu_boost_mutex; 1092 #endif /* #ifdef CONFIG_RCU_BOOST */ 1093 1094 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 1095 struct sched_info sched_info; 1096 #endif 1097 1098 struct list_head tasks; 1099 #ifdef CONFIG_SMP 1100 struct plist_node pushable_tasks; 1101 #endif 1102 1103 struct mm_struct *mm, *active_mm; 1104 #ifdef CONFIG_COMPAT_BRK 1105 unsigned brk_randomized:1; 1106 #endif 1107 #if defined(SPLIT_RSS_COUNTING) 1108 struct task_rss_stat rss_stat; 1109 #endif 1110 /* task state */ 1111 int exit_state; 1112 int exit_code, exit_signal; 1113 int pdeath_signal; /* The signal sent when the parent dies */ 1114 unsigned int jobctl; /* JOBCTL_*, siglock protected */ 1115 1116 /* Used for emulating ABI behavior of previous Linux versions */ 1117 unsigned int personality; 1118 1119 unsigned did_exec:1; 1120 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1121 * execve */ 1122 unsigned in_iowait:1; 1123 1124 /* task may not gain privileges */ 1125 unsigned no_new_privs:1; 1126 1127 /* Revert to default priority/policy when forking */ 1128 unsigned sched_reset_on_fork:1; 1129 unsigned sched_contributes_to_load:1; 1130 1131 pid_t pid; 1132 pid_t tgid; 1133 1134 #ifdef CONFIG_CC_STACKPROTECTOR 1135 /* Canary value for the -fstack-protector gcc feature */ 1136 unsigned long stack_canary; 1137 #endif 1138 /* 1139 * pointers to (original) parent process, youngest child, younger sibling, 1140 * older sibling, respectively. (p->father can be replaced with 1141 * p->real_parent->pid) 1142 */ 1143 struct task_struct __rcu *real_parent; /* real parent process */ 1144 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1145 /* 1146 * children/sibling forms the list of my natural children 1147 */ 1148 struct list_head children; /* list of my children */ 1149 struct list_head sibling; /* linkage in my parent's children list */ 1150 struct task_struct *group_leader; /* threadgroup leader */ 1151 1152 /* 1153 * ptraced is the list of tasks this task is using ptrace on. 1154 * This includes both natural children and PTRACE_ATTACH targets. 1155 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1156 */ 1157 struct list_head ptraced; 1158 struct list_head ptrace_entry; 1159 1160 /* PID/PID hash table linkage. */ 1161 struct pid_link pids[PIDTYPE_MAX]; 1162 struct list_head thread_group; 1163 1164 struct completion *vfork_done; /* for vfork() */ 1165 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1166 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1167 1168 cputime_t utime, stime, utimescaled, stimescaled; 1169 cputime_t gtime; 1170 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 1171 struct cputime prev_cputime; 1172 #endif 1173 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1174 seqlock_t vtime_seqlock; 1175 unsigned long long vtime_snap; 1176 enum { 1177 VTIME_SLEEPING = 0, 1178 VTIME_USER, 1179 VTIME_SYS, 1180 } vtime_snap_whence; 1181 #endif 1182 unsigned long nvcsw, nivcsw; /* context switch counts */ 1183 struct timespec start_time; /* monotonic time */ 1184 struct timespec real_start_time; /* boot based time */ 1185 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1186 unsigned long min_flt, maj_flt; 1187 1188 struct task_cputime cputime_expires; 1189 struct list_head cpu_timers[3]; 1190 1191 /* process credentials */ 1192 const struct cred __rcu *real_cred; /* objective and real subjective task 1193 * credentials (COW) */ 1194 const struct cred __rcu *cred; /* effective (overridable) subjective task 1195 * credentials (COW) */ 1196 char comm[TASK_COMM_LEN]; /* executable name excluding path 1197 - access with [gs]et_task_comm (which lock 1198 it with task_lock()) 1199 - initialized normally by setup_new_exec */ 1200 /* file system info */ 1201 int link_count, total_link_count; 1202 #ifdef CONFIG_SYSVIPC 1203 /* ipc stuff */ 1204 struct sysv_sem sysvsem; 1205 #endif 1206 #ifdef CONFIG_DETECT_HUNG_TASK 1207 /* hung task detection */ 1208 unsigned long last_switch_count; 1209 #endif 1210 /* CPU-specific state of this task */ 1211 struct thread_struct thread; 1212 /* filesystem information */ 1213 struct fs_struct *fs; 1214 /* open file information */ 1215 struct files_struct *files; 1216 /* namespaces */ 1217 struct nsproxy *nsproxy; 1218 /* signal handlers */ 1219 struct signal_struct *signal; 1220 struct sighand_struct *sighand; 1221 1222 sigset_t blocked, real_blocked; 1223 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1224 struct sigpending pending; 1225 1226 unsigned long sas_ss_sp; 1227 size_t sas_ss_size; 1228 int (*notifier)(void *priv); 1229 void *notifier_data; 1230 sigset_t *notifier_mask; 1231 struct callback_head *task_works; 1232 1233 struct audit_context *audit_context; 1234 #ifdef CONFIG_AUDITSYSCALL 1235 kuid_t loginuid; 1236 unsigned int sessionid; 1237 #endif 1238 struct seccomp seccomp; 1239 1240 /* Thread group tracking */ 1241 u32 parent_exec_id; 1242 u32 self_exec_id; 1243 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1244 * mempolicy */ 1245 spinlock_t alloc_lock; 1246 1247 /* Protection of the PI data structures: */ 1248 raw_spinlock_t pi_lock; 1249 1250 #ifdef CONFIG_RT_MUTEXES 1251 /* PI waiters blocked on a rt_mutex held by this task */ 1252 struct plist_head pi_waiters; 1253 /* Deadlock detection and priority inheritance handling */ 1254 struct rt_mutex_waiter *pi_blocked_on; 1255 #endif 1256 1257 #ifdef CONFIG_DEBUG_MUTEXES 1258 /* mutex deadlock detection */ 1259 struct mutex_waiter *blocked_on; 1260 #endif 1261 #ifdef CONFIG_TRACE_IRQFLAGS 1262 unsigned int irq_events; 1263 unsigned long hardirq_enable_ip; 1264 unsigned long hardirq_disable_ip; 1265 unsigned int hardirq_enable_event; 1266 unsigned int hardirq_disable_event; 1267 int hardirqs_enabled; 1268 int hardirq_context; 1269 unsigned long softirq_disable_ip; 1270 unsigned long softirq_enable_ip; 1271 unsigned int softirq_disable_event; 1272 unsigned int softirq_enable_event; 1273 int softirqs_enabled; 1274 int softirq_context; 1275 #endif 1276 #ifdef CONFIG_LOCKDEP 1277 # define MAX_LOCK_DEPTH 48UL 1278 u64 curr_chain_key; 1279 int lockdep_depth; 1280 unsigned int lockdep_recursion; 1281 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1282 gfp_t lockdep_reclaim_gfp; 1283 #endif 1284 1285 /* journalling filesystem info */ 1286 void *journal_info; 1287 1288 /* stacked block device info */ 1289 struct bio_list *bio_list; 1290 1291 #ifdef CONFIG_BLOCK 1292 /* stack plugging */ 1293 struct blk_plug *plug; 1294 #endif 1295 1296 /* VM state */ 1297 struct reclaim_state *reclaim_state; 1298 1299 struct backing_dev_info *backing_dev_info; 1300 1301 struct io_context *io_context; 1302 1303 unsigned long ptrace_message; 1304 siginfo_t *last_siginfo; /* For ptrace use. */ 1305 struct task_io_accounting ioac; 1306 #if defined(CONFIG_TASK_XACCT) 1307 u64 acct_rss_mem1; /* accumulated rss usage */ 1308 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1309 cputime_t acct_timexpd; /* stime + utime since last update */ 1310 #endif 1311 #ifdef CONFIG_CPUSETS 1312 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1313 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1314 int cpuset_mem_spread_rotor; 1315 int cpuset_slab_spread_rotor; 1316 #endif 1317 #ifdef CONFIG_CGROUPS 1318 /* Control Group info protected by css_set_lock */ 1319 struct css_set __rcu *cgroups; 1320 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1321 struct list_head cg_list; 1322 #endif 1323 #ifdef CONFIG_FUTEX 1324 struct robust_list_head __user *robust_list; 1325 #ifdef CONFIG_COMPAT 1326 struct compat_robust_list_head __user *compat_robust_list; 1327 #endif 1328 struct list_head pi_state_list; 1329 struct futex_pi_state *pi_state_cache; 1330 #endif 1331 #ifdef CONFIG_PERF_EVENTS 1332 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1333 struct mutex perf_event_mutex; 1334 struct list_head perf_event_list; 1335 #endif 1336 #ifdef CONFIG_NUMA 1337 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1338 short il_next; 1339 short pref_node_fork; 1340 #endif 1341 #ifdef CONFIG_NUMA_BALANCING 1342 int numa_scan_seq; 1343 unsigned int numa_scan_period; 1344 unsigned int numa_scan_period_max; 1345 int numa_preferred_nid; 1346 int numa_migrate_deferred; 1347 unsigned long numa_migrate_retry; 1348 u64 node_stamp; /* migration stamp */ 1349 struct callback_head numa_work; 1350 1351 struct list_head numa_entry; 1352 struct numa_group *numa_group; 1353 1354 /* 1355 * Exponential decaying average of faults on a per-node basis. 1356 * Scheduling placement decisions are made based on the these counts. 1357 * The values remain static for the duration of a PTE scan 1358 */ 1359 unsigned long *numa_faults; 1360 unsigned long total_numa_faults; 1361 1362 /* 1363 * numa_faults_buffer records faults per node during the current 1364 * scan window. When the scan completes, the counts in numa_faults 1365 * decay and these values are copied. 1366 */ 1367 unsigned long *numa_faults_buffer; 1368 1369 /* 1370 * numa_faults_locality tracks if faults recorded during the last 1371 * scan window were remote/local. The task scan period is adapted 1372 * based on the locality of the faults with different weights 1373 * depending on whether they were shared or private faults 1374 */ 1375 unsigned long numa_faults_locality[2]; 1376 1377 unsigned long numa_pages_migrated; 1378 #endif /* CONFIG_NUMA_BALANCING */ 1379 1380 struct rcu_head rcu; 1381 1382 /* 1383 * cache last used pipe for splice 1384 */ 1385 struct pipe_inode_info *splice_pipe; 1386 1387 struct page_frag task_frag; 1388 1389 #ifdef CONFIG_TASK_DELAY_ACCT 1390 struct task_delay_info *delays; 1391 #endif 1392 #ifdef CONFIG_FAULT_INJECTION 1393 int make_it_fail; 1394 #endif 1395 /* 1396 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1397 * balance_dirty_pages() for some dirty throttling pause 1398 */ 1399 int nr_dirtied; 1400 int nr_dirtied_pause; 1401 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1402 1403 #ifdef CONFIG_LATENCYTOP 1404 int latency_record_count; 1405 struct latency_record latency_record[LT_SAVECOUNT]; 1406 #endif 1407 /* 1408 * time slack values; these are used to round up poll() and 1409 * select() etc timeout values. These are in nanoseconds. 1410 */ 1411 unsigned long timer_slack_ns; 1412 unsigned long default_timer_slack_ns; 1413 1414 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1415 /* Index of current stored address in ret_stack */ 1416 int curr_ret_stack; 1417 /* Stack of return addresses for return function tracing */ 1418 struct ftrace_ret_stack *ret_stack; 1419 /* time stamp for last schedule */ 1420 unsigned long long ftrace_timestamp; 1421 /* 1422 * Number of functions that haven't been traced 1423 * because of depth overrun. 1424 */ 1425 atomic_t trace_overrun; 1426 /* Pause for the tracing */ 1427 atomic_t tracing_graph_pause; 1428 #endif 1429 #ifdef CONFIG_TRACING 1430 /* state flags for use by tracers */ 1431 unsigned long trace; 1432 /* bitmask and counter of trace recursion */ 1433 unsigned long trace_recursion; 1434 #endif /* CONFIG_TRACING */ 1435 #ifdef CONFIG_MEMCG /* memcg uses this to do batch job */ 1436 struct memcg_batch_info { 1437 int do_batch; /* incremented when batch uncharge started */ 1438 struct mem_cgroup *memcg; /* target memcg of uncharge */ 1439 unsigned long nr_pages; /* uncharged usage */ 1440 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ 1441 } memcg_batch; 1442 unsigned int memcg_kmem_skip_account; 1443 struct memcg_oom_info { 1444 struct mem_cgroup *memcg; 1445 gfp_t gfp_mask; 1446 int order; 1447 unsigned int may_oom:1; 1448 } memcg_oom; 1449 #endif 1450 #ifdef CONFIG_UPROBES 1451 struct uprobe_task *utask; 1452 #endif 1453 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1454 unsigned int sequential_io; 1455 unsigned int sequential_io_avg; 1456 #endif 1457 }; 1458 1459 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1460 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1461 1462 #define TNF_MIGRATED 0x01 1463 #define TNF_NO_GROUP 0x02 1464 #define TNF_SHARED 0x04 1465 #define TNF_FAULT_LOCAL 0x08 1466 1467 #ifdef CONFIG_NUMA_BALANCING 1468 extern void task_numa_fault(int last_node, int node, int pages, int flags); 1469 extern pid_t task_numa_group_id(struct task_struct *p); 1470 extern void set_numabalancing_state(bool enabled); 1471 extern void task_numa_free(struct task_struct *p); 1472 1473 extern unsigned int sysctl_numa_balancing_migrate_deferred; 1474 #else 1475 static inline void task_numa_fault(int last_node, int node, int pages, 1476 int flags) 1477 { 1478 } 1479 static inline pid_t task_numa_group_id(struct task_struct *p) 1480 { 1481 return 0; 1482 } 1483 static inline void set_numabalancing_state(bool enabled) 1484 { 1485 } 1486 static inline void task_numa_free(struct task_struct *p) 1487 { 1488 } 1489 #endif 1490 1491 static inline struct pid *task_pid(struct task_struct *task) 1492 { 1493 return task->pids[PIDTYPE_PID].pid; 1494 } 1495 1496 static inline struct pid *task_tgid(struct task_struct *task) 1497 { 1498 return task->group_leader->pids[PIDTYPE_PID].pid; 1499 } 1500 1501 /* 1502 * Without tasklist or rcu lock it is not safe to dereference 1503 * the result of task_pgrp/task_session even if task == current, 1504 * we can race with another thread doing sys_setsid/sys_setpgid. 1505 */ 1506 static inline struct pid *task_pgrp(struct task_struct *task) 1507 { 1508 return task->group_leader->pids[PIDTYPE_PGID].pid; 1509 } 1510 1511 static inline struct pid *task_session(struct task_struct *task) 1512 { 1513 return task->group_leader->pids[PIDTYPE_SID].pid; 1514 } 1515 1516 struct pid_namespace; 1517 1518 /* 1519 * the helpers to get the task's different pids as they are seen 1520 * from various namespaces 1521 * 1522 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1523 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1524 * current. 1525 * task_xid_nr_ns() : id seen from the ns specified; 1526 * 1527 * set_task_vxid() : assigns a virtual id to a task; 1528 * 1529 * see also pid_nr() etc in include/linux/pid.h 1530 */ 1531 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1532 struct pid_namespace *ns); 1533 1534 static inline pid_t task_pid_nr(struct task_struct *tsk) 1535 { 1536 return tsk->pid; 1537 } 1538 1539 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1540 struct pid_namespace *ns) 1541 { 1542 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1543 } 1544 1545 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1546 { 1547 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1548 } 1549 1550 1551 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1552 { 1553 return tsk->tgid; 1554 } 1555 1556 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1557 1558 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1559 { 1560 return pid_vnr(task_tgid(tsk)); 1561 } 1562 1563 1564 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1565 struct pid_namespace *ns) 1566 { 1567 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1568 } 1569 1570 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1571 { 1572 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1573 } 1574 1575 1576 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1577 struct pid_namespace *ns) 1578 { 1579 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1580 } 1581 1582 static inline pid_t task_session_vnr(struct task_struct *tsk) 1583 { 1584 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1585 } 1586 1587 /* obsolete, do not use */ 1588 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1589 { 1590 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1591 } 1592 1593 /** 1594 * pid_alive - check that a task structure is not stale 1595 * @p: Task structure to be checked. 1596 * 1597 * Test if a process is not yet dead (at most zombie state) 1598 * If pid_alive fails, then pointers within the task structure 1599 * can be stale and must not be dereferenced. 1600 * 1601 * Return: 1 if the process is alive. 0 otherwise. 1602 */ 1603 static inline int pid_alive(struct task_struct *p) 1604 { 1605 return p->pids[PIDTYPE_PID].pid != NULL; 1606 } 1607 1608 /** 1609 * is_global_init - check if a task structure is init 1610 * @tsk: Task structure to be checked. 1611 * 1612 * Check if a task structure is the first user space task the kernel created. 1613 * 1614 * Return: 1 if the task structure is init. 0 otherwise. 1615 */ 1616 static inline int is_global_init(struct task_struct *tsk) 1617 { 1618 return tsk->pid == 1; 1619 } 1620 1621 extern struct pid *cad_pid; 1622 1623 extern void free_task(struct task_struct *tsk); 1624 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1625 1626 extern void __put_task_struct(struct task_struct *t); 1627 1628 static inline void put_task_struct(struct task_struct *t) 1629 { 1630 if (atomic_dec_and_test(&t->usage)) 1631 __put_task_struct(t); 1632 } 1633 1634 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1635 extern void task_cputime(struct task_struct *t, 1636 cputime_t *utime, cputime_t *stime); 1637 extern void task_cputime_scaled(struct task_struct *t, 1638 cputime_t *utimescaled, cputime_t *stimescaled); 1639 extern cputime_t task_gtime(struct task_struct *t); 1640 #else 1641 static inline void task_cputime(struct task_struct *t, 1642 cputime_t *utime, cputime_t *stime) 1643 { 1644 if (utime) 1645 *utime = t->utime; 1646 if (stime) 1647 *stime = t->stime; 1648 } 1649 1650 static inline void task_cputime_scaled(struct task_struct *t, 1651 cputime_t *utimescaled, 1652 cputime_t *stimescaled) 1653 { 1654 if (utimescaled) 1655 *utimescaled = t->utimescaled; 1656 if (stimescaled) 1657 *stimescaled = t->stimescaled; 1658 } 1659 1660 static inline cputime_t task_gtime(struct task_struct *t) 1661 { 1662 return t->gtime; 1663 } 1664 #endif 1665 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1666 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1667 1668 /* 1669 * Per process flags 1670 */ 1671 #define PF_EXITING 0x00000004 /* getting shut down */ 1672 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1673 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 1674 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1675 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1676 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 1677 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1678 #define PF_DUMPCORE 0x00000200 /* dumped core */ 1679 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 1680 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1681 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 1682 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1683 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 1684 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1685 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1686 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1687 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 1688 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 1689 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1690 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1691 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1692 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1693 #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ 1694 #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ 1695 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 1696 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1697 #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ 1698 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1699 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1700 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 1701 1702 /* 1703 * Only the _current_ task can read/write to tsk->flags, but other 1704 * tasks can access tsk->flags in readonly mode for example 1705 * with tsk_used_math (like during threaded core dumping). 1706 * There is however an exception to this rule during ptrace 1707 * or during fork: the ptracer task is allowed to write to the 1708 * child->flags of its traced child (same goes for fork, the parent 1709 * can write to the child->flags), because we're guaranteed the 1710 * child is not running and in turn not changing child->flags 1711 * at the same time the parent does it. 1712 */ 1713 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1714 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1715 #define clear_used_math() clear_stopped_child_used_math(current) 1716 #define set_used_math() set_stopped_child_used_math(current) 1717 #define conditional_stopped_child_used_math(condition, child) \ 1718 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1719 #define conditional_used_math(condition) \ 1720 conditional_stopped_child_used_math(condition, current) 1721 #define copy_to_stopped_child_used_math(child) \ 1722 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1723 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1724 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1725 #define used_math() tsk_used_math(current) 1726 1727 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags */ 1728 static inline gfp_t memalloc_noio_flags(gfp_t flags) 1729 { 1730 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 1731 flags &= ~__GFP_IO; 1732 return flags; 1733 } 1734 1735 static inline unsigned int memalloc_noio_save(void) 1736 { 1737 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 1738 current->flags |= PF_MEMALLOC_NOIO; 1739 return flags; 1740 } 1741 1742 static inline void memalloc_noio_restore(unsigned int flags) 1743 { 1744 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 1745 } 1746 1747 /* 1748 * task->jobctl flags 1749 */ 1750 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 1751 1752 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 1753 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 1754 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 1755 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 1756 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 1757 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 1758 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 1759 1760 #define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) 1761 #define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) 1762 #define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) 1763 #define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) 1764 #define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) 1765 #define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) 1766 #define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) 1767 1768 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 1769 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 1770 1771 extern bool task_set_jobctl_pending(struct task_struct *task, 1772 unsigned int mask); 1773 extern void task_clear_jobctl_trapping(struct task_struct *task); 1774 extern void task_clear_jobctl_pending(struct task_struct *task, 1775 unsigned int mask); 1776 1777 #ifdef CONFIG_PREEMPT_RCU 1778 1779 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */ 1780 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */ 1781 1782 static inline void rcu_copy_process(struct task_struct *p) 1783 { 1784 p->rcu_read_lock_nesting = 0; 1785 p->rcu_read_unlock_special = 0; 1786 #ifdef CONFIG_TREE_PREEMPT_RCU 1787 p->rcu_blocked_node = NULL; 1788 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1789 #ifdef CONFIG_RCU_BOOST 1790 p->rcu_boost_mutex = NULL; 1791 #endif /* #ifdef CONFIG_RCU_BOOST */ 1792 INIT_LIST_HEAD(&p->rcu_node_entry); 1793 } 1794 1795 #else 1796 1797 static inline void rcu_copy_process(struct task_struct *p) 1798 { 1799 } 1800 1801 #endif 1802 1803 static inline void tsk_restore_flags(struct task_struct *task, 1804 unsigned long orig_flags, unsigned long flags) 1805 { 1806 task->flags &= ~flags; 1807 task->flags |= orig_flags & flags; 1808 } 1809 1810 #ifdef CONFIG_SMP 1811 extern void do_set_cpus_allowed(struct task_struct *p, 1812 const struct cpumask *new_mask); 1813 1814 extern int set_cpus_allowed_ptr(struct task_struct *p, 1815 const struct cpumask *new_mask); 1816 #else 1817 static inline void do_set_cpus_allowed(struct task_struct *p, 1818 const struct cpumask *new_mask) 1819 { 1820 } 1821 static inline int set_cpus_allowed_ptr(struct task_struct *p, 1822 const struct cpumask *new_mask) 1823 { 1824 if (!cpumask_test_cpu(0, new_mask)) 1825 return -EINVAL; 1826 return 0; 1827 } 1828 #endif 1829 1830 #ifdef CONFIG_NO_HZ_COMMON 1831 void calc_load_enter_idle(void); 1832 void calc_load_exit_idle(void); 1833 #else 1834 static inline void calc_load_enter_idle(void) { } 1835 static inline void calc_load_exit_idle(void) { } 1836 #endif /* CONFIG_NO_HZ_COMMON */ 1837 1838 #ifndef CONFIG_CPUMASK_OFFSTACK 1839 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 1840 { 1841 return set_cpus_allowed_ptr(p, &new_mask); 1842 } 1843 #endif 1844 1845 /* 1846 * Do not use outside of architecture code which knows its limitations. 1847 * 1848 * sched_clock() has no promise of monotonicity or bounded drift between 1849 * CPUs, use (which you should not) requires disabling IRQs. 1850 * 1851 * Please use one of the three interfaces below. 1852 */ 1853 extern unsigned long long notrace sched_clock(void); 1854 /* 1855 * See the comment in kernel/sched/clock.c 1856 */ 1857 extern u64 cpu_clock(int cpu); 1858 extern u64 local_clock(void); 1859 extern u64 sched_clock_cpu(int cpu); 1860 1861 1862 extern void sched_clock_init(void); 1863 1864 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 1865 static inline void sched_clock_tick(void) 1866 { 1867 } 1868 1869 static inline void sched_clock_idle_sleep_event(void) 1870 { 1871 } 1872 1873 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 1874 { 1875 } 1876 #else 1877 /* 1878 * Architectures can set this to 1 if they have specified 1879 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 1880 * but then during bootup it turns out that sched_clock() 1881 * is reliable after all: 1882 */ 1883 extern int sched_clock_stable; 1884 1885 extern void sched_clock_tick(void); 1886 extern void sched_clock_idle_sleep_event(void); 1887 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1888 #endif 1889 1890 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1891 /* 1892 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 1893 * The reason for this explicit opt-in is not to have perf penalty with 1894 * slow sched_clocks. 1895 */ 1896 extern void enable_sched_clock_irqtime(void); 1897 extern void disable_sched_clock_irqtime(void); 1898 #else 1899 static inline void enable_sched_clock_irqtime(void) {} 1900 static inline void disable_sched_clock_irqtime(void) {} 1901 #endif 1902 1903 extern unsigned long long 1904 task_sched_runtime(struct task_struct *task); 1905 1906 /* sched_exec is called by processes performing an exec */ 1907 #ifdef CONFIG_SMP 1908 extern void sched_exec(void); 1909 #else 1910 #define sched_exec() {} 1911 #endif 1912 1913 extern void sched_clock_idle_sleep_event(void); 1914 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1915 1916 #ifdef CONFIG_HOTPLUG_CPU 1917 extern void idle_task_exit(void); 1918 #else 1919 static inline void idle_task_exit(void) {} 1920 #endif 1921 1922 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 1923 extern void wake_up_nohz_cpu(int cpu); 1924 #else 1925 static inline void wake_up_nohz_cpu(int cpu) { } 1926 #endif 1927 1928 #ifdef CONFIG_NO_HZ_FULL 1929 extern bool sched_can_stop_tick(void); 1930 extern u64 scheduler_tick_max_deferment(void); 1931 #else 1932 static inline bool sched_can_stop_tick(void) { return false; } 1933 #endif 1934 1935 #ifdef CONFIG_SCHED_AUTOGROUP 1936 extern void sched_autogroup_create_attach(struct task_struct *p); 1937 extern void sched_autogroup_detach(struct task_struct *p); 1938 extern void sched_autogroup_fork(struct signal_struct *sig); 1939 extern void sched_autogroup_exit(struct signal_struct *sig); 1940 #ifdef CONFIG_PROC_FS 1941 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 1942 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 1943 #endif 1944 #else 1945 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 1946 static inline void sched_autogroup_detach(struct task_struct *p) { } 1947 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 1948 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 1949 #endif 1950 1951 extern bool yield_to(struct task_struct *p, bool preempt); 1952 extern void set_user_nice(struct task_struct *p, long nice); 1953 extern int task_prio(const struct task_struct *p); 1954 extern int task_nice(const struct task_struct *p); 1955 extern int can_nice(const struct task_struct *p, const int nice); 1956 extern int task_curr(const struct task_struct *p); 1957 extern int idle_cpu(int cpu); 1958 extern int sched_setscheduler(struct task_struct *, int, 1959 const struct sched_param *); 1960 extern int sched_setscheduler_nocheck(struct task_struct *, int, 1961 const struct sched_param *); 1962 extern struct task_struct *idle_task(int cpu); 1963 /** 1964 * is_idle_task - is the specified task an idle task? 1965 * @p: the task in question. 1966 * 1967 * Return: 1 if @p is an idle task. 0 otherwise. 1968 */ 1969 static inline bool is_idle_task(const struct task_struct *p) 1970 { 1971 return p->pid == 0; 1972 } 1973 extern struct task_struct *curr_task(int cpu); 1974 extern void set_curr_task(int cpu, struct task_struct *p); 1975 1976 void yield(void); 1977 1978 /* 1979 * The default (Linux) execution domain. 1980 */ 1981 extern struct exec_domain default_exec_domain; 1982 1983 union thread_union { 1984 struct thread_info thread_info; 1985 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1986 }; 1987 1988 #ifndef __HAVE_ARCH_KSTACK_END 1989 static inline int kstack_end(void *addr) 1990 { 1991 /* Reliable end of stack detection: 1992 * Some APM bios versions misalign the stack 1993 */ 1994 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 1995 } 1996 #endif 1997 1998 extern union thread_union init_thread_union; 1999 extern struct task_struct init_task; 2000 2001 extern struct mm_struct init_mm; 2002 2003 extern struct pid_namespace init_pid_ns; 2004 2005 /* 2006 * find a task by one of its numerical ids 2007 * 2008 * find_task_by_pid_ns(): 2009 * finds a task by its pid in the specified namespace 2010 * find_task_by_vpid(): 2011 * finds a task by its virtual pid 2012 * 2013 * see also find_vpid() etc in include/linux/pid.h 2014 */ 2015 2016 extern struct task_struct *find_task_by_vpid(pid_t nr); 2017 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2018 struct pid_namespace *ns); 2019 2020 /* per-UID process charging. */ 2021 extern struct user_struct * alloc_uid(kuid_t); 2022 static inline struct user_struct *get_uid(struct user_struct *u) 2023 { 2024 atomic_inc(&u->__count); 2025 return u; 2026 } 2027 extern void free_uid(struct user_struct *); 2028 2029 #include <asm/current.h> 2030 2031 extern void xtime_update(unsigned long ticks); 2032 2033 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2034 extern int wake_up_process(struct task_struct *tsk); 2035 extern void wake_up_new_task(struct task_struct *tsk); 2036 #ifdef CONFIG_SMP 2037 extern void kick_process(struct task_struct *tsk); 2038 #else 2039 static inline void kick_process(struct task_struct *tsk) { } 2040 #endif 2041 extern void sched_fork(unsigned long clone_flags, struct task_struct *p); 2042 extern void sched_dead(struct task_struct *p); 2043 2044 extern void proc_caches_init(void); 2045 extern void flush_signals(struct task_struct *); 2046 extern void __flush_signals(struct task_struct *); 2047 extern void ignore_signals(struct task_struct *); 2048 extern void flush_signal_handlers(struct task_struct *, int force_default); 2049 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2050 2051 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2052 { 2053 unsigned long flags; 2054 int ret; 2055 2056 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2057 ret = dequeue_signal(tsk, mask, info); 2058 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2059 2060 return ret; 2061 } 2062 2063 extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2064 sigset_t *mask); 2065 extern void unblock_all_signals(void); 2066 extern void release_task(struct task_struct * p); 2067 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2068 extern int force_sigsegv(int, struct task_struct *); 2069 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2070 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2071 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2072 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2073 const struct cred *, u32); 2074 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2075 extern int kill_pid(struct pid *pid, int sig, int priv); 2076 extern int kill_proc_info(int, struct siginfo *, pid_t); 2077 extern __must_check bool do_notify_parent(struct task_struct *, int); 2078 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2079 extern void force_sig(int, struct task_struct *); 2080 extern int send_sig(int, struct task_struct *, int); 2081 extern int zap_other_threads(struct task_struct *p); 2082 extern struct sigqueue *sigqueue_alloc(void); 2083 extern void sigqueue_free(struct sigqueue *); 2084 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2085 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2086 2087 static inline void restore_saved_sigmask(void) 2088 { 2089 if (test_and_clear_restore_sigmask()) 2090 __set_current_blocked(¤t->saved_sigmask); 2091 } 2092 2093 static inline sigset_t *sigmask_to_save(void) 2094 { 2095 sigset_t *res = ¤t->blocked; 2096 if (unlikely(test_restore_sigmask())) 2097 res = ¤t->saved_sigmask; 2098 return res; 2099 } 2100 2101 static inline int kill_cad_pid(int sig, int priv) 2102 { 2103 return kill_pid(cad_pid, sig, priv); 2104 } 2105 2106 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2107 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2108 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2109 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2110 2111 /* 2112 * True if we are on the alternate signal stack. 2113 */ 2114 static inline int on_sig_stack(unsigned long sp) 2115 { 2116 #ifdef CONFIG_STACK_GROWSUP 2117 return sp >= current->sas_ss_sp && 2118 sp - current->sas_ss_sp < current->sas_ss_size; 2119 #else 2120 return sp > current->sas_ss_sp && 2121 sp - current->sas_ss_sp <= current->sas_ss_size; 2122 #endif 2123 } 2124 2125 static inline int sas_ss_flags(unsigned long sp) 2126 { 2127 return (current->sas_ss_size == 0 ? SS_DISABLE 2128 : on_sig_stack(sp) ? SS_ONSTACK : 0); 2129 } 2130 2131 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2132 { 2133 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2134 #ifdef CONFIG_STACK_GROWSUP 2135 return current->sas_ss_sp; 2136 #else 2137 return current->sas_ss_sp + current->sas_ss_size; 2138 #endif 2139 return sp; 2140 } 2141 2142 /* 2143 * Routines for handling mm_structs 2144 */ 2145 extern struct mm_struct * mm_alloc(void); 2146 2147 /* mmdrop drops the mm and the page tables */ 2148 extern void __mmdrop(struct mm_struct *); 2149 static inline void mmdrop(struct mm_struct * mm) 2150 { 2151 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2152 __mmdrop(mm); 2153 } 2154 2155 /* mmput gets rid of the mappings and all user-space */ 2156 extern void mmput(struct mm_struct *); 2157 /* Grab a reference to a task's mm, if it is not already going away */ 2158 extern struct mm_struct *get_task_mm(struct task_struct *task); 2159 /* 2160 * Grab a reference to a task's mm, if it is not already going away 2161 * and ptrace_may_access with the mode parameter passed to it 2162 * succeeds. 2163 */ 2164 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2165 /* Remove the current tasks stale references to the old mm_struct */ 2166 extern void mm_release(struct task_struct *, struct mm_struct *); 2167 /* Allocate a new mm structure and copy contents from tsk->mm */ 2168 extern struct mm_struct *dup_mm(struct task_struct *tsk); 2169 2170 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2171 struct task_struct *); 2172 extern void flush_thread(void); 2173 extern void exit_thread(void); 2174 2175 extern void exit_files(struct task_struct *); 2176 extern void __cleanup_sighand(struct sighand_struct *); 2177 2178 extern void exit_itimers(struct signal_struct *); 2179 extern void flush_itimer_signals(void); 2180 2181 extern void do_group_exit(int); 2182 2183 extern int allow_signal(int); 2184 extern int disallow_signal(int); 2185 2186 extern int do_execve(const char *, 2187 const char __user * const __user *, 2188 const char __user * const __user *); 2189 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2190 struct task_struct *fork_idle(int); 2191 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2192 2193 extern void set_task_comm(struct task_struct *tsk, char *from); 2194 extern char *get_task_comm(char *to, struct task_struct *tsk); 2195 2196 #ifdef CONFIG_SMP 2197 void scheduler_ipi(void); 2198 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2199 #else 2200 static inline void scheduler_ipi(void) { } 2201 static inline unsigned long wait_task_inactive(struct task_struct *p, 2202 long match_state) 2203 { 2204 return 1; 2205 } 2206 #endif 2207 2208 #define next_task(p) \ 2209 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2210 2211 #define for_each_process(p) \ 2212 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2213 2214 extern bool current_is_single_threaded(void); 2215 2216 /* 2217 * Careful: do_each_thread/while_each_thread is a double loop so 2218 * 'break' will not work as expected - use goto instead. 2219 */ 2220 #define do_each_thread(g, t) \ 2221 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2222 2223 #define while_each_thread(g, t) \ 2224 while ((t = next_thread(t)) != g) 2225 2226 static inline int get_nr_threads(struct task_struct *tsk) 2227 { 2228 return tsk->signal->nr_threads; 2229 } 2230 2231 static inline bool thread_group_leader(struct task_struct *p) 2232 { 2233 return p->exit_signal >= 0; 2234 } 2235 2236 /* Do to the insanities of de_thread it is possible for a process 2237 * to have the pid of the thread group leader without actually being 2238 * the thread group leader. For iteration through the pids in proc 2239 * all we care about is that we have a task with the appropriate 2240 * pid, we don't actually care if we have the right task. 2241 */ 2242 static inline bool has_group_leader_pid(struct task_struct *p) 2243 { 2244 return task_pid(p) == p->signal->leader_pid; 2245 } 2246 2247 static inline 2248 bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 2249 { 2250 return p1->signal == p2->signal; 2251 } 2252 2253 static inline struct task_struct *next_thread(const struct task_struct *p) 2254 { 2255 return list_entry_rcu(p->thread_group.next, 2256 struct task_struct, thread_group); 2257 } 2258 2259 static inline int thread_group_empty(struct task_struct *p) 2260 { 2261 return list_empty(&p->thread_group); 2262 } 2263 2264 #define delay_group_leader(p) \ 2265 (thread_group_leader(p) && !thread_group_empty(p)) 2266 2267 /* 2268 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2269 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2270 * pins the final release of task.io_context. Also protects ->cpuset and 2271 * ->cgroup.subsys[]. And ->vfork_done. 2272 * 2273 * Nests both inside and outside of read_lock(&tasklist_lock). 2274 * It must not be nested with write_lock_irq(&tasklist_lock), 2275 * neither inside nor outside. 2276 */ 2277 static inline void task_lock(struct task_struct *p) 2278 { 2279 spin_lock(&p->alloc_lock); 2280 } 2281 2282 static inline void task_unlock(struct task_struct *p) 2283 { 2284 spin_unlock(&p->alloc_lock); 2285 } 2286 2287 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2288 unsigned long *flags); 2289 2290 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2291 unsigned long *flags) 2292 { 2293 struct sighand_struct *ret; 2294 2295 ret = __lock_task_sighand(tsk, flags); 2296 (void)__cond_lock(&tsk->sighand->siglock, ret); 2297 return ret; 2298 } 2299 2300 static inline void unlock_task_sighand(struct task_struct *tsk, 2301 unsigned long *flags) 2302 { 2303 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2304 } 2305 2306 #ifdef CONFIG_CGROUPS 2307 static inline void threadgroup_change_begin(struct task_struct *tsk) 2308 { 2309 down_read(&tsk->signal->group_rwsem); 2310 } 2311 static inline void threadgroup_change_end(struct task_struct *tsk) 2312 { 2313 up_read(&tsk->signal->group_rwsem); 2314 } 2315 2316 /** 2317 * threadgroup_lock - lock threadgroup 2318 * @tsk: member task of the threadgroup to lock 2319 * 2320 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter 2321 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or 2322 * change ->group_leader/pid. This is useful for cases where the threadgroup 2323 * needs to stay stable across blockable operations. 2324 * 2325 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for 2326 * synchronization. While held, no new task will be added to threadgroup 2327 * and no existing live task will have its PF_EXITING set. 2328 * 2329 * de_thread() does threadgroup_change_{begin|end}() when a non-leader 2330 * sub-thread becomes a new leader. 2331 */ 2332 static inline void threadgroup_lock(struct task_struct *tsk) 2333 { 2334 down_write(&tsk->signal->group_rwsem); 2335 } 2336 2337 /** 2338 * threadgroup_unlock - unlock threadgroup 2339 * @tsk: member task of the threadgroup to unlock 2340 * 2341 * Reverse threadgroup_lock(). 2342 */ 2343 static inline void threadgroup_unlock(struct task_struct *tsk) 2344 { 2345 up_write(&tsk->signal->group_rwsem); 2346 } 2347 #else 2348 static inline void threadgroup_change_begin(struct task_struct *tsk) {} 2349 static inline void threadgroup_change_end(struct task_struct *tsk) {} 2350 static inline void threadgroup_lock(struct task_struct *tsk) {} 2351 static inline void threadgroup_unlock(struct task_struct *tsk) {} 2352 #endif 2353 2354 #ifndef __HAVE_THREAD_FUNCTIONS 2355 2356 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 2357 #define task_stack_page(task) ((task)->stack) 2358 2359 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2360 { 2361 *task_thread_info(p) = *task_thread_info(org); 2362 task_thread_info(p)->task = p; 2363 } 2364 2365 static inline unsigned long *end_of_stack(struct task_struct *p) 2366 { 2367 return (unsigned long *)(task_thread_info(p) + 1); 2368 } 2369 2370 #endif 2371 2372 static inline int object_is_on_stack(void *obj) 2373 { 2374 void *stack = task_stack_page(current); 2375 2376 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2377 } 2378 2379 extern void thread_info_cache_init(void); 2380 2381 #ifdef CONFIG_DEBUG_STACK_USAGE 2382 static inline unsigned long stack_not_used(struct task_struct *p) 2383 { 2384 unsigned long *n = end_of_stack(p); 2385 2386 do { /* Skip over canary */ 2387 n++; 2388 } while (!*n); 2389 2390 return (unsigned long)n - (unsigned long)end_of_stack(p); 2391 } 2392 #endif 2393 2394 /* set thread flags in other task's structures 2395 * - see asm/thread_info.h for TIF_xxxx flags available 2396 */ 2397 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2398 { 2399 set_ti_thread_flag(task_thread_info(tsk), flag); 2400 } 2401 2402 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2403 { 2404 clear_ti_thread_flag(task_thread_info(tsk), flag); 2405 } 2406 2407 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2408 { 2409 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2410 } 2411 2412 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2413 { 2414 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2415 } 2416 2417 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2418 { 2419 return test_ti_thread_flag(task_thread_info(tsk), flag); 2420 } 2421 2422 static inline void set_tsk_need_resched(struct task_struct *tsk) 2423 { 2424 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2425 } 2426 2427 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2428 { 2429 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2430 } 2431 2432 static inline int test_tsk_need_resched(struct task_struct *tsk) 2433 { 2434 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2435 } 2436 2437 static inline int restart_syscall(void) 2438 { 2439 set_tsk_thread_flag(current, TIF_SIGPENDING); 2440 return -ERESTARTNOINTR; 2441 } 2442 2443 static inline int signal_pending(struct task_struct *p) 2444 { 2445 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2446 } 2447 2448 static inline int __fatal_signal_pending(struct task_struct *p) 2449 { 2450 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2451 } 2452 2453 static inline int fatal_signal_pending(struct task_struct *p) 2454 { 2455 return signal_pending(p) && __fatal_signal_pending(p); 2456 } 2457 2458 static inline int signal_pending_state(long state, struct task_struct *p) 2459 { 2460 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2461 return 0; 2462 if (!signal_pending(p)) 2463 return 0; 2464 2465 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2466 } 2467 2468 /* 2469 * cond_resched() and cond_resched_lock(): latency reduction via 2470 * explicit rescheduling in places that are safe. The return 2471 * value indicates whether a reschedule was done in fact. 2472 * cond_resched_lock() will drop the spinlock before scheduling, 2473 * cond_resched_softirq() will enable bhs before scheduling. 2474 */ 2475 extern int _cond_resched(void); 2476 2477 #define cond_resched() ({ \ 2478 __might_sleep(__FILE__, __LINE__, 0); \ 2479 _cond_resched(); \ 2480 }) 2481 2482 extern int __cond_resched_lock(spinlock_t *lock); 2483 2484 #ifdef CONFIG_PREEMPT_COUNT 2485 #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2486 #else 2487 #define PREEMPT_LOCK_OFFSET 0 2488 #endif 2489 2490 #define cond_resched_lock(lock) ({ \ 2491 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2492 __cond_resched_lock(lock); \ 2493 }) 2494 2495 extern int __cond_resched_softirq(void); 2496 2497 #define cond_resched_softirq() ({ \ 2498 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2499 __cond_resched_softirq(); \ 2500 }) 2501 2502 static inline void cond_resched_rcu(void) 2503 { 2504 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 2505 rcu_read_unlock(); 2506 cond_resched(); 2507 rcu_read_lock(); 2508 #endif 2509 } 2510 2511 /* 2512 * Does a critical section need to be broken due to another 2513 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2514 * but a general need for low latency) 2515 */ 2516 static inline int spin_needbreak(spinlock_t *lock) 2517 { 2518 #ifdef CONFIG_PREEMPT 2519 return spin_is_contended(lock); 2520 #else 2521 return 0; 2522 #endif 2523 } 2524 2525 /* 2526 * Idle thread specific functions to determine the need_resched 2527 * polling state. We have two versions, one based on TS_POLLING in 2528 * thread_info.status and one based on TIF_POLLING_NRFLAG in 2529 * thread_info.flags 2530 */ 2531 #ifdef TS_POLLING 2532 static inline int tsk_is_polling(struct task_struct *p) 2533 { 2534 return task_thread_info(p)->status & TS_POLLING; 2535 } 2536 static inline void __current_set_polling(void) 2537 { 2538 current_thread_info()->status |= TS_POLLING; 2539 } 2540 2541 static inline bool __must_check current_set_polling_and_test(void) 2542 { 2543 __current_set_polling(); 2544 2545 /* 2546 * Polling state must be visible before we test NEED_RESCHED, 2547 * paired by resched_task() 2548 */ 2549 smp_mb(); 2550 2551 return unlikely(tif_need_resched()); 2552 } 2553 2554 static inline void __current_clr_polling(void) 2555 { 2556 current_thread_info()->status &= ~TS_POLLING; 2557 } 2558 2559 static inline bool __must_check current_clr_polling_and_test(void) 2560 { 2561 __current_clr_polling(); 2562 2563 /* 2564 * Polling state must be visible before we test NEED_RESCHED, 2565 * paired by resched_task() 2566 */ 2567 smp_mb(); 2568 2569 return unlikely(tif_need_resched()); 2570 } 2571 #elif defined(TIF_POLLING_NRFLAG) 2572 static inline int tsk_is_polling(struct task_struct *p) 2573 { 2574 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 2575 } 2576 2577 static inline void __current_set_polling(void) 2578 { 2579 set_thread_flag(TIF_POLLING_NRFLAG); 2580 } 2581 2582 static inline bool __must_check current_set_polling_and_test(void) 2583 { 2584 __current_set_polling(); 2585 2586 /* 2587 * Polling state must be visible before we test NEED_RESCHED, 2588 * paired by resched_task() 2589 * 2590 * XXX: assumes set/clear bit are identical barrier wise. 2591 */ 2592 smp_mb__after_clear_bit(); 2593 2594 return unlikely(tif_need_resched()); 2595 } 2596 2597 static inline void __current_clr_polling(void) 2598 { 2599 clear_thread_flag(TIF_POLLING_NRFLAG); 2600 } 2601 2602 static inline bool __must_check current_clr_polling_and_test(void) 2603 { 2604 __current_clr_polling(); 2605 2606 /* 2607 * Polling state must be visible before we test NEED_RESCHED, 2608 * paired by resched_task() 2609 */ 2610 smp_mb__after_clear_bit(); 2611 2612 return unlikely(tif_need_resched()); 2613 } 2614 2615 #else 2616 static inline int tsk_is_polling(struct task_struct *p) { return 0; } 2617 static inline void __current_set_polling(void) { } 2618 static inline void __current_clr_polling(void) { } 2619 2620 static inline bool __must_check current_set_polling_and_test(void) 2621 { 2622 return unlikely(tif_need_resched()); 2623 } 2624 static inline bool __must_check current_clr_polling_and_test(void) 2625 { 2626 return unlikely(tif_need_resched()); 2627 } 2628 #endif 2629 2630 static __always_inline bool need_resched(void) 2631 { 2632 return unlikely(tif_need_resched()); 2633 } 2634 2635 /* 2636 * Thread group CPU time accounting. 2637 */ 2638 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 2639 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 2640 2641 static inline void thread_group_cputime_init(struct signal_struct *sig) 2642 { 2643 raw_spin_lock_init(&sig->cputimer.lock); 2644 } 2645 2646 /* 2647 * Reevaluate whether the task has signals pending delivery. 2648 * Wake the task if so. 2649 * This is required every time the blocked sigset_t changes. 2650 * callers must hold sighand->siglock. 2651 */ 2652 extern void recalc_sigpending_and_wake(struct task_struct *t); 2653 extern void recalc_sigpending(void); 2654 2655 extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 2656 2657 static inline void signal_wake_up(struct task_struct *t, bool resume) 2658 { 2659 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 2660 } 2661 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 2662 { 2663 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 2664 } 2665 2666 /* 2667 * Wrappers for p->thread_info->cpu access. No-op on UP. 2668 */ 2669 #ifdef CONFIG_SMP 2670 2671 static inline unsigned int task_cpu(const struct task_struct *p) 2672 { 2673 return task_thread_info(p)->cpu; 2674 } 2675 2676 static inline int task_node(const struct task_struct *p) 2677 { 2678 return cpu_to_node(task_cpu(p)); 2679 } 2680 2681 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2682 2683 #else 2684 2685 static inline unsigned int task_cpu(const struct task_struct *p) 2686 { 2687 return 0; 2688 } 2689 2690 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2691 { 2692 } 2693 2694 #endif /* CONFIG_SMP */ 2695 2696 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2697 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2698 2699 #ifdef CONFIG_CGROUP_SCHED 2700 extern struct task_group root_task_group; 2701 #endif /* CONFIG_CGROUP_SCHED */ 2702 2703 extern int task_can_switch_user(struct user_struct *up, 2704 struct task_struct *tsk); 2705 2706 #ifdef CONFIG_TASK_XACCT 2707 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2708 { 2709 tsk->ioac.rchar += amt; 2710 } 2711 2712 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2713 { 2714 tsk->ioac.wchar += amt; 2715 } 2716 2717 static inline void inc_syscr(struct task_struct *tsk) 2718 { 2719 tsk->ioac.syscr++; 2720 } 2721 2722 static inline void inc_syscw(struct task_struct *tsk) 2723 { 2724 tsk->ioac.syscw++; 2725 } 2726 #else 2727 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2728 { 2729 } 2730 2731 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2732 { 2733 } 2734 2735 static inline void inc_syscr(struct task_struct *tsk) 2736 { 2737 } 2738 2739 static inline void inc_syscw(struct task_struct *tsk) 2740 { 2741 } 2742 #endif 2743 2744 #ifndef TASK_SIZE_OF 2745 #define TASK_SIZE_OF(tsk) TASK_SIZE 2746 #endif 2747 2748 #ifdef CONFIG_MM_OWNER 2749 extern void mm_update_next_owner(struct mm_struct *mm); 2750 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); 2751 #else 2752 static inline void mm_update_next_owner(struct mm_struct *mm) 2753 { 2754 } 2755 2756 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) 2757 { 2758 } 2759 #endif /* CONFIG_MM_OWNER */ 2760 2761 static inline unsigned long task_rlimit(const struct task_struct *tsk, 2762 unsigned int limit) 2763 { 2764 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); 2765 } 2766 2767 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 2768 unsigned int limit) 2769 { 2770 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); 2771 } 2772 2773 static inline unsigned long rlimit(unsigned int limit) 2774 { 2775 return task_rlimit(current, limit); 2776 } 2777 2778 static inline unsigned long rlimit_max(unsigned int limit) 2779 { 2780 return task_rlimit_max(current, limit); 2781 } 2782 2783 #endif 2784