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 #define PREEMPT_ENABLED (PREEMPT_NEED_RESCHED) 444 445 #ifdef CONFIG_PREEMPT_COUNT 446 #define PREEMPT_DISABLED (1 + PREEMPT_ENABLED) 447 #else 448 #define PREEMPT_DISABLED PREEMPT_ENABLED 449 #endif 450 451 /* 452 * Disable preemption until the scheduler is running. 453 * Reset by start_kernel()->sched_init()->init_idle(). 454 * 455 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 456 * before the scheduler is active -- see should_resched(). 457 */ 458 #define INIT_PREEMPT_COUNT (PREEMPT_DISABLED + PREEMPT_ACTIVE) 459 460 /** 461 * struct thread_group_cputimer - thread group interval timer counts 462 * @cputime: thread group interval timers. 463 * @running: non-zero when there are timers running and 464 * @cputime receives updates. 465 * @lock: lock for fields in this struct. 466 * 467 * This structure contains the version of task_cputime, above, that is 468 * used for thread group CPU timer calculations. 469 */ 470 struct thread_group_cputimer { 471 struct task_cputime cputime; 472 int running; 473 raw_spinlock_t lock; 474 }; 475 476 #include <linux/rwsem.h> 477 struct autogroup; 478 479 /* 480 * NOTE! "signal_struct" does not have its own 481 * locking, because a shared signal_struct always 482 * implies a shared sighand_struct, so locking 483 * sighand_struct is always a proper superset of 484 * the locking of signal_struct. 485 */ 486 struct signal_struct { 487 atomic_t sigcnt; 488 atomic_t live; 489 int nr_threads; 490 491 wait_queue_head_t wait_chldexit; /* for wait4() */ 492 493 /* current thread group signal load-balancing target: */ 494 struct task_struct *curr_target; 495 496 /* shared signal handling: */ 497 struct sigpending shared_pending; 498 499 /* thread group exit support */ 500 int group_exit_code; 501 /* overloaded: 502 * - notify group_exit_task when ->count is equal to notify_count 503 * - everyone except group_exit_task is stopped during signal delivery 504 * of fatal signals, group_exit_task processes the signal. 505 */ 506 int notify_count; 507 struct task_struct *group_exit_task; 508 509 /* thread group stop support, overloads group_exit_code too */ 510 int group_stop_count; 511 unsigned int flags; /* see SIGNAL_* flags below */ 512 513 /* 514 * PR_SET_CHILD_SUBREAPER marks a process, like a service 515 * manager, to re-parent orphan (double-forking) child processes 516 * to this process instead of 'init'. The service manager is 517 * able to receive SIGCHLD signals and is able to investigate 518 * the process until it calls wait(). All children of this 519 * process will inherit a flag if they should look for a 520 * child_subreaper process at exit. 521 */ 522 unsigned int is_child_subreaper:1; 523 unsigned int has_child_subreaper:1; 524 525 /* POSIX.1b Interval Timers */ 526 int posix_timer_id; 527 struct list_head posix_timers; 528 529 /* ITIMER_REAL timer for the process */ 530 struct hrtimer real_timer; 531 struct pid *leader_pid; 532 ktime_t it_real_incr; 533 534 /* 535 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 536 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 537 * values are defined to 0 and 1 respectively 538 */ 539 struct cpu_itimer it[2]; 540 541 /* 542 * Thread group totals for process CPU timers. 543 * See thread_group_cputimer(), et al, for details. 544 */ 545 struct thread_group_cputimer cputimer; 546 547 /* Earliest-expiration cache. */ 548 struct task_cputime cputime_expires; 549 550 struct list_head cpu_timers[3]; 551 552 struct pid *tty_old_pgrp; 553 554 /* boolean value for session group leader */ 555 int leader; 556 557 struct tty_struct *tty; /* NULL if no tty */ 558 559 #ifdef CONFIG_SCHED_AUTOGROUP 560 struct autogroup *autogroup; 561 #endif 562 /* 563 * Cumulative resource counters for dead threads in the group, 564 * and for reaped dead child processes forked by this group. 565 * Live threads maintain their own counters and add to these 566 * in __exit_signal, except for the group leader. 567 */ 568 cputime_t utime, stime, cutime, cstime; 569 cputime_t gtime; 570 cputime_t cgtime; 571 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 572 struct cputime prev_cputime; 573 #endif 574 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 575 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 576 unsigned long inblock, oublock, cinblock, coublock; 577 unsigned long maxrss, cmaxrss; 578 struct task_io_accounting ioac; 579 580 /* 581 * Cumulative ns of schedule CPU time fo dead threads in the 582 * group, not including a zombie group leader, (This only differs 583 * from jiffies_to_ns(utime + stime) if sched_clock uses something 584 * other than jiffies.) 585 */ 586 unsigned long long sum_sched_runtime; 587 588 /* 589 * We don't bother to synchronize most readers of this at all, 590 * because there is no reader checking a limit that actually needs 591 * to get both rlim_cur and rlim_max atomically, and either one 592 * alone is a single word that can safely be read normally. 593 * getrlimit/setrlimit use task_lock(current->group_leader) to 594 * protect this instead of the siglock, because they really 595 * have no need to disable irqs. 596 */ 597 struct rlimit rlim[RLIM_NLIMITS]; 598 599 #ifdef CONFIG_BSD_PROCESS_ACCT 600 struct pacct_struct pacct; /* per-process accounting information */ 601 #endif 602 #ifdef CONFIG_TASKSTATS 603 struct taskstats *stats; 604 #endif 605 #ifdef CONFIG_AUDIT 606 unsigned audit_tty; 607 unsigned audit_tty_log_passwd; 608 struct tty_audit_buf *tty_audit_buf; 609 #endif 610 #ifdef CONFIG_CGROUPS 611 /* 612 * group_rwsem prevents new tasks from entering the threadgroup and 613 * member tasks from exiting,a more specifically, setting of 614 * PF_EXITING. fork and exit paths are protected with this rwsem 615 * using threadgroup_change_begin/end(). Users which require 616 * threadgroup to remain stable should use threadgroup_[un]lock() 617 * which also takes care of exec path. Currently, cgroup is the 618 * only user. 619 */ 620 struct rw_semaphore group_rwsem; 621 #endif 622 623 oom_flags_t oom_flags; 624 short oom_score_adj; /* OOM kill score adjustment */ 625 short oom_score_adj_min; /* OOM kill score adjustment min value. 626 * Only settable by CAP_SYS_RESOURCE. */ 627 628 struct mutex cred_guard_mutex; /* guard against foreign influences on 629 * credential calculations 630 * (notably. ptrace) */ 631 }; 632 633 /* 634 * Bits in flags field of signal_struct. 635 */ 636 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 637 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 638 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 639 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 640 /* 641 * Pending notifications to parent. 642 */ 643 #define SIGNAL_CLD_STOPPED 0x00000010 644 #define SIGNAL_CLD_CONTINUED 0x00000020 645 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 646 647 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 648 649 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 650 static inline int signal_group_exit(const struct signal_struct *sig) 651 { 652 return (sig->flags & SIGNAL_GROUP_EXIT) || 653 (sig->group_exit_task != NULL); 654 } 655 656 /* 657 * Some day this will be a full-fledged user tracking system.. 658 */ 659 struct user_struct { 660 atomic_t __count; /* reference count */ 661 atomic_t processes; /* How many processes does this user have? */ 662 atomic_t files; /* How many open files does this user have? */ 663 atomic_t sigpending; /* How many pending signals does this user have? */ 664 #ifdef CONFIG_INOTIFY_USER 665 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 666 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 667 #endif 668 #ifdef CONFIG_FANOTIFY 669 atomic_t fanotify_listeners; 670 #endif 671 #ifdef CONFIG_EPOLL 672 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 673 #endif 674 #ifdef CONFIG_POSIX_MQUEUE 675 /* protected by mq_lock */ 676 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 677 #endif 678 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 679 680 #ifdef CONFIG_KEYS 681 struct key *uid_keyring; /* UID specific keyring */ 682 struct key *session_keyring; /* UID's default session keyring */ 683 #endif 684 685 /* Hash table maintenance information */ 686 struct hlist_node uidhash_node; 687 kuid_t uid; 688 689 #ifdef CONFIG_PERF_EVENTS 690 atomic_long_t locked_vm; 691 #endif 692 }; 693 694 extern int uids_sysfs_init(void); 695 696 extern struct user_struct *find_user(kuid_t); 697 698 extern struct user_struct root_user; 699 #define INIT_USER (&root_user) 700 701 702 struct backing_dev_info; 703 struct reclaim_state; 704 705 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 706 struct sched_info { 707 /* cumulative counters */ 708 unsigned long pcount; /* # of times run on this cpu */ 709 unsigned long long run_delay; /* time spent waiting on a runqueue */ 710 711 /* timestamps */ 712 unsigned long long last_arrival,/* when we last ran on a cpu */ 713 last_queued; /* when we were last queued to run */ 714 }; 715 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ 716 717 #ifdef CONFIG_TASK_DELAY_ACCT 718 struct task_delay_info { 719 spinlock_t lock; 720 unsigned int flags; /* Private per-task flags */ 721 722 /* For each stat XXX, add following, aligned appropriately 723 * 724 * struct timespec XXX_start, XXX_end; 725 * u64 XXX_delay; 726 * u32 XXX_count; 727 * 728 * Atomicity of updates to XXX_delay, XXX_count protected by 729 * single lock above (split into XXX_lock if contention is an issue). 730 */ 731 732 /* 733 * XXX_count is incremented on every XXX operation, the delay 734 * associated with the operation is added to XXX_delay. 735 * XXX_delay contains the accumulated delay time in nanoseconds. 736 */ 737 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ 738 u64 blkio_delay; /* wait for sync block io completion */ 739 u64 swapin_delay; /* wait for swapin block io completion */ 740 u32 blkio_count; /* total count of the number of sync block */ 741 /* io operations performed */ 742 u32 swapin_count; /* total count of the number of swapin block */ 743 /* io operations performed */ 744 745 struct timespec freepages_start, freepages_end; 746 u64 freepages_delay; /* wait for memory reclaim */ 747 u32 freepages_count; /* total count of memory reclaim */ 748 }; 749 #endif /* CONFIG_TASK_DELAY_ACCT */ 750 751 static inline int sched_info_on(void) 752 { 753 #ifdef CONFIG_SCHEDSTATS 754 return 1; 755 #elif defined(CONFIG_TASK_DELAY_ACCT) 756 extern int delayacct_on; 757 return delayacct_on; 758 #else 759 return 0; 760 #endif 761 } 762 763 enum cpu_idle_type { 764 CPU_IDLE, 765 CPU_NOT_IDLE, 766 CPU_NEWLY_IDLE, 767 CPU_MAX_IDLE_TYPES 768 }; 769 770 /* 771 * Increase resolution of cpu_power calculations 772 */ 773 #define SCHED_POWER_SHIFT 10 774 #define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT) 775 776 /* 777 * sched-domains (multiprocessor balancing) declarations: 778 */ 779 #ifdef CONFIG_SMP 780 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 781 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 782 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 783 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 784 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 785 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 786 #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ 787 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 788 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 789 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 790 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 791 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 792 #define SD_NUMA 0x4000 /* cross-node balancing */ 793 794 extern int __weak arch_sd_sibiling_asym_packing(void); 795 796 struct sched_domain_attr { 797 int relax_domain_level; 798 }; 799 800 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 801 .relax_domain_level = -1, \ 802 } 803 804 extern int sched_domain_level_max; 805 806 struct sched_group; 807 808 struct sched_domain { 809 /* These fields must be setup */ 810 struct sched_domain *parent; /* top domain must be null terminated */ 811 struct sched_domain *child; /* bottom domain must be null terminated */ 812 struct sched_group *groups; /* the balancing groups of the domain */ 813 unsigned long min_interval; /* Minimum balance interval ms */ 814 unsigned long max_interval; /* Maximum balance interval ms */ 815 unsigned int busy_factor; /* less balancing by factor if busy */ 816 unsigned int imbalance_pct; /* No balance until over watermark */ 817 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 818 unsigned int busy_idx; 819 unsigned int idle_idx; 820 unsigned int newidle_idx; 821 unsigned int wake_idx; 822 unsigned int forkexec_idx; 823 unsigned int smt_gain; 824 825 int nohz_idle; /* NOHZ IDLE status */ 826 int flags; /* See SD_* */ 827 int level; 828 829 /* Runtime fields. */ 830 unsigned long last_balance; /* init to jiffies. units in jiffies */ 831 unsigned int balance_interval; /* initialise to 1. units in ms. */ 832 unsigned int nr_balance_failed; /* initialise to 0 */ 833 834 /* idle_balance() stats */ 835 u64 max_newidle_lb_cost; 836 unsigned long next_decay_max_lb_cost; 837 838 #ifdef CONFIG_SCHEDSTATS 839 /* load_balance() stats */ 840 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 841 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 842 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 843 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 844 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 845 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 846 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 847 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 848 849 /* Active load balancing */ 850 unsigned int alb_count; 851 unsigned int alb_failed; 852 unsigned int alb_pushed; 853 854 /* SD_BALANCE_EXEC stats */ 855 unsigned int sbe_count; 856 unsigned int sbe_balanced; 857 unsigned int sbe_pushed; 858 859 /* SD_BALANCE_FORK stats */ 860 unsigned int sbf_count; 861 unsigned int sbf_balanced; 862 unsigned int sbf_pushed; 863 864 /* try_to_wake_up() stats */ 865 unsigned int ttwu_wake_remote; 866 unsigned int ttwu_move_affine; 867 unsigned int ttwu_move_balance; 868 #endif 869 #ifdef CONFIG_SCHED_DEBUG 870 char *name; 871 #endif 872 union { 873 void *private; /* used during construction */ 874 struct rcu_head rcu; /* used during destruction */ 875 }; 876 877 unsigned int span_weight; 878 /* 879 * Span of all CPUs in this domain. 880 * 881 * NOTE: this field is variable length. (Allocated dynamically 882 * by attaching extra space to the end of the structure, 883 * depending on how many CPUs the kernel has booted up with) 884 */ 885 unsigned long span[0]; 886 }; 887 888 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 889 { 890 return to_cpumask(sd->span); 891 } 892 893 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 894 struct sched_domain_attr *dattr_new); 895 896 /* Allocate an array of sched domains, for partition_sched_domains(). */ 897 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 898 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 899 900 bool cpus_share_cache(int this_cpu, int that_cpu); 901 902 #else /* CONFIG_SMP */ 903 904 struct sched_domain_attr; 905 906 static inline void 907 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 908 struct sched_domain_attr *dattr_new) 909 { 910 } 911 912 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 913 { 914 return true; 915 } 916 917 #endif /* !CONFIG_SMP */ 918 919 920 struct io_context; /* See blkdev.h */ 921 922 923 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 924 extern void prefetch_stack(struct task_struct *t); 925 #else 926 static inline void prefetch_stack(struct task_struct *t) { } 927 #endif 928 929 struct audit_context; /* See audit.c */ 930 struct mempolicy; 931 struct pipe_inode_info; 932 struct uts_namespace; 933 934 struct load_weight { 935 unsigned long weight, inv_weight; 936 }; 937 938 struct sched_avg { 939 /* 940 * These sums represent an infinite geometric series and so are bound 941 * above by 1024/(1-y). Thus we only need a u32 to store them for all 942 * choices of y < 1-2^(-32)*1024. 943 */ 944 u32 runnable_avg_sum, runnable_avg_period; 945 u64 last_runnable_update; 946 s64 decay_count; 947 unsigned long load_avg_contrib; 948 }; 949 950 #ifdef CONFIG_SCHEDSTATS 951 struct sched_statistics { 952 u64 wait_start; 953 u64 wait_max; 954 u64 wait_count; 955 u64 wait_sum; 956 u64 iowait_count; 957 u64 iowait_sum; 958 959 u64 sleep_start; 960 u64 sleep_max; 961 s64 sum_sleep_runtime; 962 963 u64 block_start; 964 u64 block_max; 965 u64 exec_max; 966 u64 slice_max; 967 968 u64 nr_migrations_cold; 969 u64 nr_failed_migrations_affine; 970 u64 nr_failed_migrations_running; 971 u64 nr_failed_migrations_hot; 972 u64 nr_forced_migrations; 973 974 u64 nr_wakeups; 975 u64 nr_wakeups_sync; 976 u64 nr_wakeups_migrate; 977 u64 nr_wakeups_local; 978 u64 nr_wakeups_remote; 979 u64 nr_wakeups_affine; 980 u64 nr_wakeups_affine_attempts; 981 u64 nr_wakeups_passive; 982 u64 nr_wakeups_idle; 983 }; 984 #endif 985 986 struct sched_entity { 987 struct load_weight load; /* for load-balancing */ 988 struct rb_node run_node; 989 struct list_head group_node; 990 unsigned int on_rq; 991 992 u64 exec_start; 993 u64 sum_exec_runtime; 994 u64 vruntime; 995 u64 prev_sum_exec_runtime; 996 997 u64 nr_migrations; 998 999 #ifdef CONFIG_SCHEDSTATS 1000 struct sched_statistics statistics; 1001 #endif 1002 1003 #ifdef CONFIG_FAIR_GROUP_SCHED 1004 struct sched_entity *parent; 1005 /* rq on which this entity is (to be) queued: */ 1006 struct cfs_rq *cfs_rq; 1007 /* rq "owned" by this entity/group: */ 1008 struct cfs_rq *my_q; 1009 #endif 1010 1011 #ifdef CONFIG_SMP 1012 /* Per-entity load-tracking */ 1013 struct sched_avg avg; 1014 #endif 1015 }; 1016 1017 struct sched_rt_entity { 1018 struct list_head run_list; 1019 unsigned long timeout; 1020 unsigned long watchdog_stamp; 1021 unsigned int time_slice; 1022 1023 struct sched_rt_entity *back; 1024 #ifdef CONFIG_RT_GROUP_SCHED 1025 struct sched_rt_entity *parent; 1026 /* rq on which this entity is (to be) queued: */ 1027 struct rt_rq *rt_rq; 1028 /* rq "owned" by this entity/group: */ 1029 struct rt_rq *my_q; 1030 #endif 1031 }; 1032 1033 1034 struct rcu_node; 1035 1036 enum perf_event_task_context { 1037 perf_invalid_context = -1, 1038 perf_hw_context = 0, 1039 perf_sw_context, 1040 perf_nr_task_contexts, 1041 }; 1042 1043 struct task_struct { 1044 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1045 void *stack; 1046 atomic_t usage; 1047 unsigned int flags; /* per process flags, defined below */ 1048 unsigned int ptrace; 1049 1050 #ifdef CONFIG_SMP 1051 struct llist_node wake_entry; 1052 int on_cpu; 1053 struct task_struct *last_wakee; 1054 unsigned long wakee_flips; 1055 unsigned long wakee_flip_decay_ts; 1056 1057 int wake_cpu; 1058 #endif 1059 int on_rq; 1060 1061 int prio, static_prio, normal_prio; 1062 unsigned int rt_priority; 1063 const struct sched_class *sched_class; 1064 struct sched_entity se; 1065 struct sched_rt_entity rt; 1066 #ifdef CONFIG_CGROUP_SCHED 1067 struct task_group *sched_task_group; 1068 #endif 1069 1070 #ifdef CONFIG_PREEMPT_NOTIFIERS 1071 /* list of struct preempt_notifier: */ 1072 struct hlist_head preempt_notifiers; 1073 #endif 1074 1075 #ifdef CONFIG_BLK_DEV_IO_TRACE 1076 unsigned int btrace_seq; 1077 #endif 1078 1079 unsigned int policy; 1080 int nr_cpus_allowed; 1081 cpumask_t cpus_allowed; 1082 1083 #ifdef CONFIG_PREEMPT_RCU 1084 int rcu_read_lock_nesting; 1085 char rcu_read_unlock_special; 1086 struct list_head rcu_node_entry; 1087 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1088 #ifdef CONFIG_TREE_PREEMPT_RCU 1089 struct rcu_node *rcu_blocked_node; 1090 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1091 #ifdef CONFIG_RCU_BOOST 1092 struct rt_mutex *rcu_boost_mutex; 1093 #endif /* #ifdef CONFIG_RCU_BOOST */ 1094 1095 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 1096 struct sched_info sched_info; 1097 #endif 1098 1099 struct list_head tasks; 1100 #ifdef CONFIG_SMP 1101 struct plist_node pushable_tasks; 1102 #endif 1103 1104 struct mm_struct *mm, *active_mm; 1105 #ifdef CONFIG_COMPAT_BRK 1106 unsigned brk_randomized:1; 1107 #endif 1108 #if defined(SPLIT_RSS_COUNTING) 1109 struct task_rss_stat rss_stat; 1110 #endif 1111 /* task state */ 1112 int exit_state; 1113 int exit_code, exit_signal; 1114 int pdeath_signal; /* The signal sent when the parent dies */ 1115 unsigned int jobctl; /* JOBCTL_*, siglock protected */ 1116 1117 /* Used for emulating ABI behavior of previous Linux versions */ 1118 unsigned int personality; 1119 1120 unsigned did_exec:1; 1121 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1122 * execve */ 1123 unsigned in_iowait:1; 1124 1125 /* task may not gain privileges */ 1126 unsigned no_new_privs:1; 1127 1128 /* Revert to default priority/policy when forking */ 1129 unsigned sched_reset_on_fork:1; 1130 unsigned sched_contributes_to_load:1; 1131 1132 pid_t pid; 1133 pid_t tgid; 1134 1135 #ifdef CONFIG_CC_STACKPROTECTOR 1136 /* Canary value for the -fstack-protector gcc feature */ 1137 unsigned long stack_canary; 1138 #endif 1139 /* 1140 * pointers to (original) parent process, youngest child, younger sibling, 1141 * older sibling, respectively. (p->father can be replaced with 1142 * p->real_parent->pid) 1143 */ 1144 struct task_struct __rcu *real_parent; /* real parent process */ 1145 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1146 /* 1147 * children/sibling forms the list of my natural children 1148 */ 1149 struct list_head children; /* list of my children */ 1150 struct list_head sibling; /* linkage in my parent's children list */ 1151 struct task_struct *group_leader; /* threadgroup leader */ 1152 1153 /* 1154 * ptraced is the list of tasks this task is using ptrace on. 1155 * This includes both natural children and PTRACE_ATTACH targets. 1156 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1157 */ 1158 struct list_head ptraced; 1159 struct list_head ptrace_entry; 1160 1161 /* PID/PID hash table linkage. */ 1162 struct pid_link pids[PIDTYPE_MAX]; 1163 struct list_head thread_group; 1164 1165 struct completion *vfork_done; /* for vfork() */ 1166 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1167 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1168 1169 cputime_t utime, stime, utimescaled, stimescaled; 1170 cputime_t gtime; 1171 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 1172 struct cputime prev_cputime; 1173 #endif 1174 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1175 seqlock_t vtime_seqlock; 1176 unsigned long long vtime_snap; 1177 enum { 1178 VTIME_SLEEPING = 0, 1179 VTIME_USER, 1180 VTIME_SYS, 1181 } vtime_snap_whence; 1182 #endif 1183 unsigned long nvcsw, nivcsw; /* context switch counts */ 1184 struct timespec start_time; /* monotonic time */ 1185 struct timespec real_start_time; /* boot based time */ 1186 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1187 unsigned long min_flt, maj_flt; 1188 1189 struct task_cputime cputime_expires; 1190 struct list_head cpu_timers[3]; 1191 1192 /* process credentials */ 1193 const struct cred __rcu *real_cred; /* objective and real subjective task 1194 * credentials (COW) */ 1195 const struct cred __rcu *cred; /* effective (overridable) subjective task 1196 * credentials (COW) */ 1197 char comm[TASK_COMM_LEN]; /* executable name excluding path 1198 - access with [gs]et_task_comm (which lock 1199 it with task_lock()) 1200 - initialized normally by setup_new_exec */ 1201 /* file system info */ 1202 int link_count, total_link_count; 1203 #ifdef CONFIG_SYSVIPC 1204 /* ipc stuff */ 1205 struct sysv_sem sysvsem; 1206 #endif 1207 #ifdef CONFIG_DETECT_HUNG_TASK 1208 /* hung task detection */ 1209 unsigned long last_switch_count; 1210 #endif 1211 /* CPU-specific state of this task */ 1212 struct thread_struct thread; 1213 /* filesystem information */ 1214 struct fs_struct *fs; 1215 /* open file information */ 1216 struct files_struct *files; 1217 /* namespaces */ 1218 struct nsproxy *nsproxy; 1219 /* signal handlers */ 1220 struct signal_struct *signal; 1221 struct sighand_struct *sighand; 1222 1223 sigset_t blocked, real_blocked; 1224 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1225 struct sigpending pending; 1226 1227 unsigned long sas_ss_sp; 1228 size_t sas_ss_size; 1229 int (*notifier)(void *priv); 1230 void *notifier_data; 1231 sigset_t *notifier_mask; 1232 struct callback_head *task_works; 1233 1234 struct audit_context *audit_context; 1235 #ifdef CONFIG_AUDITSYSCALL 1236 kuid_t loginuid; 1237 unsigned int sessionid; 1238 #endif 1239 struct seccomp seccomp; 1240 1241 /* Thread group tracking */ 1242 u32 parent_exec_id; 1243 u32 self_exec_id; 1244 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1245 * mempolicy */ 1246 spinlock_t alloc_lock; 1247 1248 /* Protection of the PI data structures: */ 1249 raw_spinlock_t pi_lock; 1250 1251 #ifdef CONFIG_RT_MUTEXES 1252 /* PI waiters blocked on a rt_mutex held by this task */ 1253 struct plist_head pi_waiters; 1254 /* Deadlock detection and priority inheritance handling */ 1255 struct rt_mutex_waiter *pi_blocked_on; 1256 #endif 1257 1258 #ifdef CONFIG_DEBUG_MUTEXES 1259 /* mutex deadlock detection */ 1260 struct mutex_waiter *blocked_on; 1261 #endif 1262 #ifdef CONFIG_TRACE_IRQFLAGS 1263 unsigned int irq_events; 1264 unsigned long hardirq_enable_ip; 1265 unsigned long hardirq_disable_ip; 1266 unsigned int hardirq_enable_event; 1267 unsigned int hardirq_disable_event; 1268 int hardirqs_enabled; 1269 int hardirq_context; 1270 unsigned long softirq_disable_ip; 1271 unsigned long softirq_enable_ip; 1272 unsigned int softirq_disable_event; 1273 unsigned int softirq_enable_event; 1274 int softirqs_enabled; 1275 int softirq_context; 1276 #endif 1277 #ifdef CONFIG_LOCKDEP 1278 # define MAX_LOCK_DEPTH 48UL 1279 u64 curr_chain_key; 1280 int lockdep_depth; 1281 unsigned int lockdep_recursion; 1282 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1283 gfp_t lockdep_reclaim_gfp; 1284 #endif 1285 1286 /* journalling filesystem info */ 1287 void *journal_info; 1288 1289 /* stacked block device info */ 1290 struct bio_list *bio_list; 1291 1292 #ifdef CONFIG_BLOCK 1293 /* stack plugging */ 1294 struct blk_plug *plug; 1295 #endif 1296 1297 /* VM state */ 1298 struct reclaim_state *reclaim_state; 1299 1300 struct backing_dev_info *backing_dev_info; 1301 1302 struct io_context *io_context; 1303 1304 unsigned long ptrace_message; 1305 siginfo_t *last_siginfo; /* For ptrace use. */ 1306 struct task_io_accounting ioac; 1307 #if defined(CONFIG_TASK_XACCT) 1308 u64 acct_rss_mem1; /* accumulated rss usage */ 1309 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1310 cputime_t acct_timexpd; /* stime + utime since last update */ 1311 #endif 1312 #ifdef CONFIG_CPUSETS 1313 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1314 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1315 int cpuset_mem_spread_rotor; 1316 int cpuset_slab_spread_rotor; 1317 #endif 1318 #ifdef CONFIG_CGROUPS 1319 /* Control Group info protected by css_set_lock */ 1320 struct css_set __rcu *cgroups; 1321 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1322 struct list_head cg_list; 1323 #endif 1324 #ifdef CONFIG_FUTEX 1325 struct robust_list_head __user *robust_list; 1326 #ifdef CONFIG_COMPAT 1327 struct compat_robust_list_head __user *compat_robust_list; 1328 #endif 1329 struct list_head pi_state_list; 1330 struct futex_pi_state *pi_state_cache; 1331 #endif 1332 #ifdef CONFIG_PERF_EVENTS 1333 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1334 struct mutex perf_event_mutex; 1335 struct list_head perf_event_list; 1336 #endif 1337 #ifdef CONFIG_NUMA 1338 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1339 short il_next; 1340 short pref_node_fork; 1341 #endif 1342 #ifdef CONFIG_NUMA_BALANCING 1343 int numa_scan_seq; 1344 unsigned int numa_scan_period; 1345 unsigned int numa_scan_period_max; 1346 int numa_preferred_nid; 1347 int numa_migrate_deferred; 1348 unsigned long numa_migrate_retry; 1349 u64 node_stamp; /* migration stamp */ 1350 struct callback_head numa_work; 1351 1352 struct list_head numa_entry; 1353 struct numa_group *numa_group; 1354 1355 /* 1356 * Exponential decaying average of faults on a per-node basis. 1357 * Scheduling placement decisions are made based on the these counts. 1358 * The values remain static for the duration of a PTE scan 1359 */ 1360 unsigned long *numa_faults; 1361 unsigned long total_numa_faults; 1362 1363 /* 1364 * numa_faults_buffer records faults per node during the current 1365 * scan window. When the scan completes, the counts in numa_faults 1366 * decay and these values are copied. 1367 */ 1368 unsigned long *numa_faults_buffer; 1369 1370 /* 1371 * numa_faults_locality tracks if faults recorded during the last 1372 * scan window were remote/local. The task scan period is adapted 1373 * based on the locality of the faults with different weights 1374 * depending on whether they were shared or private faults 1375 */ 1376 unsigned long numa_faults_locality[2]; 1377 1378 unsigned long numa_pages_migrated; 1379 #endif /* CONFIG_NUMA_BALANCING */ 1380 1381 struct rcu_head rcu; 1382 1383 /* 1384 * cache last used pipe for splice 1385 */ 1386 struct pipe_inode_info *splice_pipe; 1387 1388 struct page_frag task_frag; 1389 1390 #ifdef CONFIG_TASK_DELAY_ACCT 1391 struct task_delay_info *delays; 1392 #endif 1393 #ifdef CONFIG_FAULT_INJECTION 1394 int make_it_fail; 1395 #endif 1396 /* 1397 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1398 * balance_dirty_pages() for some dirty throttling pause 1399 */ 1400 int nr_dirtied; 1401 int nr_dirtied_pause; 1402 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1403 1404 #ifdef CONFIG_LATENCYTOP 1405 int latency_record_count; 1406 struct latency_record latency_record[LT_SAVECOUNT]; 1407 #endif 1408 /* 1409 * time slack values; these are used to round up poll() and 1410 * select() etc timeout values. These are in nanoseconds. 1411 */ 1412 unsigned long timer_slack_ns; 1413 unsigned long default_timer_slack_ns; 1414 1415 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1416 /* Index of current stored address in ret_stack */ 1417 int curr_ret_stack; 1418 /* Stack of return addresses for return function tracing */ 1419 struct ftrace_ret_stack *ret_stack; 1420 /* time stamp for last schedule */ 1421 unsigned long long ftrace_timestamp; 1422 /* 1423 * Number of functions that haven't been traced 1424 * because of depth overrun. 1425 */ 1426 atomic_t trace_overrun; 1427 /* Pause for the tracing */ 1428 atomic_t tracing_graph_pause; 1429 #endif 1430 #ifdef CONFIG_TRACING 1431 /* state flags for use by tracers */ 1432 unsigned long trace; 1433 /* bitmask and counter of trace recursion */ 1434 unsigned long trace_recursion; 1435 #endif /* CONFIG_TRACING */ 1436 #ifdef CONFIG_MEMCG /* memcg uses this to do batch job */ 1437 struct memcg_batch_info { 1438 int do_batch; /* incremented when batch uncharge started */ 1439 struct mem_cgroup *memcg; /* target memcg of uncharge */ 1440 unsigned long nr_pages; /* uncharged usage */ 1441 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ 1442 } memcg_batch; 1443 unsigned int memcg_kmem_skip_account; 1444 struct memcg_oom_info { 1445 struct mem_cgroup *memcg; 1446 gfp_t gfp_mask; 1447 int order; 1448 unsigned int may_oom:1; 1449 } memcg_oom; 1450 #endif 1451 #ifdef CONFIG_UPROBES 1452 struct uprobe_task *utask; 1453 #endif 1454 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1455 unsigned int sequential_io; 1456 unsigned int sequential_io_avg; 1457 #endif 1458 }; 1459 1460 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1461 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1462 1463 #define TNF_MIGRATED 0x01 1464 #define TNF_NO_GROUP 0x02 1465 #define TNF_SHARED 0x04 1466 #define TNF_FAULT_LOCAL 0x08 1467 1468 #ifdef CONFIG_NUMA_BALANCING 1469 extern void task_numa_fault(int last_node, int node, int pages, int flags); 1470 extern pid_t task_numa_group_id(struct task_struct *p); 1471 extern void set_numabalancing_state(bool enabled); 1472 extern void task_numa_free(struct task_struct *p); 1473 1474 extern unsigned int sysctl_numa_balancing_migrate_deferred; 1475 #else 1476 static inline void task_numa_fault(int last_node, int node, int pages, 1477 int flags) 1478 { 1479 } 1480 static inline pid_t task_numa_group_id(struct task_struct *p) 1481 { 1482 return 0; 1483 } 1484 static inline void set_numabalancing_state(bool enabled) 1485 { 1486 } 1487 static inline void task_numa_free(struct task_struct *p) 1488 { 1489 } 1490 #endif 1491 1492 static inline struct pid *task_pid(struct task_struct *task) 1493 { 1494 return task->pids[PIDTYPE_PID].pid; 1495 } 1496 1497 static inline struct pid *task_tgid(struct task_struct *task) 1498 { 1499 return task->group_leader->pids[PIDTYPE_PID].pid; 1500 } 1501 1502 /* 1503 * Without tasklist or rcu lock it is not safe to dereference 1504 * the result of task_pgrp/task_session even if task == current, 1505 * we can race with another thread doing sys_setsid/sys_setpgid. 1506 */ 1507 static inline struct pid *task_pgrp(struct task_struct *task) 1508 { 1509 return task->group_leader->pids[PIDTYPE_PGID].pid; 1510 } 1511 1512 static inline struct pid *task_session(struct task_struct *task) 1513 { 1514 return task->group_leader->pids[PIDTYPE_SID].pid; 1515 } 1516 1517 struct pid_namespace; 1518 1519 /* 1520 * the helpers to get the task's different pids as they are seen 1521 * from various namespaces 1522 * 1523 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1524 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1525 * current. 1526 * task_xid_nr_ns() : id seen from the ns specified; 1527 * 1528 * set_task_vxid() : assigns a virtual id to a task; 1529 * 1530 * see also pid_nr() etc in include/linux/pid.h 1531 */ 1532 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1533 struct pid_namespace *ns); 1534 1535 static inline pid_t task_pid_nr(struct task_struct *tsk) 1536 { 1537 return tsk->pid; 1538 } 1539 1540 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1541 struct pid_namespace *ns) 1542 { 1543 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1544 } 1545 1546 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1547 { 1548 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1549 } 1550 1551 1552 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1553 { 1554 return tsk->tgid; 1555 } 1556 1557 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1558 1559 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1560 { 1561 return pid_vnr(task_tgid(tsk)); 1562 } 1563 1564 1565 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1566 struct pid_namespace *ns) 1567 { 1568 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1569 } 1570 1571 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1572 { 1573 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1574 } 1575 1576 1577 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1578 struct pid_namespace *ns) 1579 { 1580 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1581 } 1582 1583 static inline pid_t task_session_vnr(struct task_struct *tsk) 1584 { 1585 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1586 } 1587 1588 /* obsolete, do not use */ 1589 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1590 { 1591 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1592 } 1593 1594 /** 1595 * pid_alive - check that a task structure is not stale 1596 * @p: Task structure to be checked. 1597 * 1598 * Test if a process is not yet dead (at most zombie state) 1599 * If pid_alive fails, then pointers within the task structure 1600 * can be stale and must not be dereferenced. 1601 * 1602 * Return: 1 if the process is alive. 0 otherwise. 1603 */ 1604 static inline int pid_alive(struct task_struct *p) 1605 { 1606 return p->pids[PIDTYPE_PID].pid != NULL; 1607 } 1608 1609 /** 1610 * is_global_init - check if a task structure is init 1611 * @tsk: Task structure to be checked. 1612 * 1613 * Check if a task structure is the first user space task the kernel created. 1614 * 1615 * Return: 1 if the task structure is init. 0 otherwise. 1616 */ 1617 static inline int is_global_init(struct task_struct *tsk) 1618 { 1619 return tsk->pid == 1; 1620 } 1621 1622 extern struct pid *cad_pid; 1623 1624 extern void free_task(struct task_struct *tsk); 1625 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1626 1627 extern void __put_task_struct(struct task_struct *t); 1628 1629 static inline void put_task_struct(struct task_struct *t) 1630 { 1631 if (atomic_dec_and_test(&t->usage)) 1632 __put_task_struct(t); 1633 } 1634 1635 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1636 extern void task_cputime(struct task_struct *t, 1637 cputime_t *utime, cputime_t *stime); 1638 extern void task_cputime_scaled(struct task_struct *t, 1639 cputime_t *utimescaled, cputime_t *stimescaled); 1640 extern cputime_t task_gtime(struct task_struct *t); 1641 #else 1642 static inline void task_cputime(struct task_struct *t, 1643 cputime_t *utime, cputime_t *stime) 1644 { 1645 if (utime) 1646 *utime = t->utime; 1647 if (stime) 1648 *stime = t->stime; 1649 } 1650 1651 static inline void task_cputime_scaled(struct task_struct *t, 1652 cputime_t *utimescaled, 1653 cputime_t *stimescaled) 1654 { 1655 if (utimescaled) 1656 *utimescaled = t->utimescaled; 1657 if (stimescaled) 1658 *stimescaled = t->stimescaled; 1659 } 1660 1661 static inline cputime_t task_gtime(struct task_struct *t) 1662 { 1663 return t->gtime; 1664 } 1665 #endif 1666 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1667 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 1668 1669 /* 1670 * Per process flags 1671 */ 1672 #define PF_EXITING 0x00000004 /* getting shut down */ 1673 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1674 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 1675 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1676 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1677 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 1678 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1679 #define PF_DUMPCORE 0x00000200 /* dumped core */ 1680 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 1681 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1682 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 1683 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1684 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 1685 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1686 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1687 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1688 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 1689 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 1690 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1691 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1692 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1693 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1694 #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ 1695 #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ 1696 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 1697 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1698 #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ 1699 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1700 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1701 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 1702 1703 /* 1704 * Only the _current_ task can read/write to tsk->flags, but other 1705 * tasks can access tsk->flags in readonly mode for example 1706 * with tsk_used_math (like during threaded core dumping). 1707 * There is however an exception to this rule during ptrace 1708 * or during fork: the ptracer task is allowed to write to the 1709 * child->flags of its traced child (same goes for fork, the parent 1710 * can write to the child->flags), because we're guaranteed the 1711 * child is not running and in turn not changing child->flags 1712 * at the same time the parent does it. 1713 */ 1714 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1715 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1716 #define clear_used_math() clear_stopped_child_used_math(current) 1717 #define set_used_math() set_stopped_child_used_math(current) 1718 #define conditional_stopped_child_used_math(condition, child) \ 1719 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1720 #define conditional_used_math(condition) \ 1721 conditional_stopped_child_used_math(condition, current) 1722 #define copy_to_stopped_child_used_math(child) \ 1723 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1724 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1725 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1726 #define used_math() tsk_used_math(current) 1727 1728 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags */ 1729 static inline gfp_t memalloc_noio_flags(gfp_t flags) 1730 { 1731 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 1732 flags &= ~__GFP_IO; 1733 return flags; 1734 } 1735 1736 static inline unsigned int memalloc_noio_save(void) 1737 { 1738 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 1739 current->flags |= PF_MEMALLOC_NOIO; 1740 return flags; 1741 } 1742 1743 static inline void memalloc_noio_restore(unsigned int flags) 1744 { 1745 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 1746 } 1747 1748 /* 1749 * task->jobctl flags 1750 */ 1751 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 1752 1753 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 1754 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 1755 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 1756 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 1757 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 1758 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 1759 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 1760 1761 #define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) 1762 #define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) 1763 #define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) 1764 #define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) 1765 #define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) 1766 #define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) 1767 #define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) 1768 1769 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 1770 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 1771 1772 extern bool task_set_jobctl_pending(struct task_struct *task, 1773 unsigned int mask); 1774 extern void task_clear_jobctl_trapping(struct task_struct *task); 1775 extern void task_clear_jobctl_pending(struct task_struct *task, 1776 unsigned int mask); 1777 1778 #ifdef CONFIG_PREEMPT_RCU 1779 1780 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */ 1781 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */ 1782 1783 static inline void rcu_copy_process(struct task_struct *p) 1784 { 1785 p->rcu_read_lock_nesting = 0; 1786 p->rcu_read_unlock_special = 0; 1787 #ifdef CONFIG_TREE_PREEMPT_RCU 1788 p->rcu_blocked_node = NULL; 1789 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1790 #ifdef CONFIG_RCU_BOOST 1791 p->rcu_boost_mutex = NULL; 1792 #endif /* #ifdef CONFIG_RCU_BOOST */ 1793 INIT_LIST_HEAD(&p->rcu_node_entry); 1794 } 1795 1796 #else 1797 1798 static inline void rcu_copy_process(struct task_struct *p) 1799 { 1800 } 1801 1802 #endif 1803 1804 static inline void tsk_restore_flags(struct task_struct *task, 1805 unsigned long orig_flags, unsigned long flags) 1806 { 1807 task->flags &= ~flags; 1808 task->flags |= orig_flags & flags; 1809 } 1810 1811 #ifdef CONFIG_SMP 1812 extern void do_set_cpus_allowed(struct task_struct *p, 1813 const struct cpumask *new_mask); 1814 1815 extern int set_cpus_allowed_ptr(struct task_struct *p, 1816 const struct cpumask *new_mask); 1817 #else 1818 static inline void do_set_cpus_allowed(struct task_struct *p, 1819 const struct cpumask *new_mask) 1820 { 1821 } 1822 static inline int set_cpus_allowed_ptr(struct task_struct *p, 1823 const struct cpumask *new_mask) 1824 { 1825 if (!cpumask_test_cpu(0, new_mask)) 1826 return -EINVAL; 1827 return 0; 1828 } 1829 #endif 1830 1831 #ifdef CONFIG_NO_HZ_COMMON 1832 void calc_load_enter_idle(void); 1833 void calc_load_exit_idle(void); 1834 #else 1835 static inline void calc_load_enter_idle(void) { } 1836 static inline void calc_load_exit_idle(void) { } 1837 #endif /* CONFIG_NO_HZ_COMMON */ 1838 1839 #ifndef CONFIG_CPUMASK_OFFSTACK 1840 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 1841 { 1842 return set_cpus_allowed_ptr(p, &new_mask); 1843 } 1844 #endif 1845 1846 /* 1847 * Do not use outside of architecture code which knows its limitations. 1848 * 1849 * sched_clock() has no promise of monotonicity or bounded drift between 1850 * CPUs, use (which you should not) requires disabling IRQs. 1851 * 1852 * Please use one of the three interfaces below. 1853 */ 1854 extern unsigned long long notrace sched_clock(void); 1855 /* 1856 * See the comment in kernel/sched/clock.c 1857 */ 1858 extern u64 cpu_clock(int cpu); 1859 extern u64 local_clock(void); 1860 extern u64 sched_clock_cpu(int cpu); 1861 1862 1863 extern void sched_clock_init(void); 1864 1865 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 1866 static inline void sched_clock_tick(void) 1867 { 1868 } 1869 1870 static inline void sched_clock_idle_sleep_event(void) 1871 { 1872 } 1873 1874 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 1875 { 1876 } 1877 #else 1878 /* 1879 * Architectures can set this to 1 if they have specified 1880 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 1881 * but then during bootup it turns out that sched_clock() 1882 * is reliable after all: 1883 */ 1884 extern int sched_clock_stable; 1885 1886 extern void sched_clock_tick(void); 1887 extern void sched_clock_idle_sleep_event(void); 1888 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1889 #endif 1890 1891 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1892 /* 1893 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 1894 * The reason for this explicit opt-in is not to have perf penalty with 1895 * slow sched_clocks. 1896 */ 1897 extern void enable_sched_clock_irqtime(void); 1898 extern void disable_sched_clock_irqtime(void); 1899 #else 1900 static inline void enable_sched_clock_irqtime(void) {} 1901 static inline void disable_sched_clock_irqtime(void) {} 1902 #endif 1903 1904 extern unsigned long long 1905 task_sched_runtime(struct task_struct *task); 1906 1907 /* sched_exec is called by processes performing an exec */ 1908 #ifdef CONFIG_SMP 1909 extern void sched_exec(void); 1910 #else 1911 #define sched_exec() {} 1912 #endif 1913 1914 extern void sched_clock_idle_sleep_event(void); 1915 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1916 1917 #ifdef CONFIG_HOTPLUG_CPU 1918 extern void idle_task_exit(void); 1919 #else 1920 static inline void idle_task_exit(void) {} 1921 #endif 1922 1923 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 1924 extern void wake_up_nohz_cpu(int cpu); 1925 #else 1926 static inline void wake_up_nohz_cpu(int cpu) { } 1927 #endif 1928 1929 #ifdef CONFIG_NO_HZ_FULL 1930 extern bool sched_can_stop_tick(void); 1931 extern u64 scheduler_tick_max_deferment(void); 1932 #else 1933 static inline bool sched_can_stop_tick(void) { return false; } 1934 #endif 1935 1936 #ifdef CONFIG_SCHED_AUTOGROUP 1937 extern void sched_autogroup_create_attach(struct task_struct *p); 1938 extern void sched_autogroup_detach(struct task_struct *p); 1939 extern void sched_autogroup_fork(struct signal_struct *sig); 1940 extern void sched_autogroup_exit(struct signal_struct *sig); 1941 #ifdef CONFIG_PROC_FS 1942 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 1943 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 1944 #endif 1945 #else 1946 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 1947 static inline void sched_autogroup_detach(struct task_struct *p) { } 1948 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 1949 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 1950 #endif 1951 1952 extern bool yield_to(struct task_struct *p, bool preempt); 1953 extern void set_user_nice(struct task_struct *p, long nice); 1954 extern int task_prio(const struct task_struct *p); 1955 extern int task_nice(const struct task_struct *p); 1956 extern int can_nice(const struct task_struct *p, const int nice); 1957 extern int task_curr(const struct task_struct *p); 1958 extern int idle_cpu(int cpu); 1959 extern int sched_setscheduler(struct task_struct *, int, 1960 const struct sched_param *); 1961 extern int sched_setscheduler_nocheck(struct task_struct *, int, 1962 const struct sched_param *); 1963 extern struct task_struct *idle_task(int cpu); 1964 /** 1965 * is_idle_task - is the specified task an idle task? 1966 * @p: the task in question. 1967 * 1968 * Return: 1 if @p is an idle task. 0 otherwise. 1969 */ 1970 static inline bool is_idle_task(const struct task_struct *p) 1971 { 1972 return p->pid == 0; 1973 } 1974 extern struct task_struct *curr_task(int cpu); 1975 extern void set_curr_task(int cpu, struct task_struct *p); 1976 1977 void yield(void); 1978 1979 /* 1980 * The default (Linux) execution domain. 1981 */ 1982 extern struct exec_domain default_exec_domain; 1983 1984 union thread_union { 1985 struct thread_info thread_info; 1986 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1987 }; 1988 1989 #ifndef __HAVE_ARCH_KSTACK_END 1990 static inline int kstack_end(void *addr) 1991 { 1992 /* Reliable end of stack detection: 1993 * Some APM bios versions misalign the stack 1994 */ 1995 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 1996 } 1997 #endif 1998 1999 extern union thread_union init_thread_union; 2000 extern struct task_struct init_task; 2001 2002 extern struct mm_struct init_mm; 2003 2004 extern struct pid_namespace init_pid_ns; 2005 2006 /* 2007 * find a task by one of its numerical ids 2008 * 2009 * find_task_by_pid_ns(): 2010 * finds a task by its pid in the specified namespace 2011 * find_task_by_vpid(): 2012 * finds a task by its virtual pid 2013 * 2014 * see also find_vpid() etc in include/linux/pid.h 2015 */ 2016 2017 extern struct task_struct *find_task_by_vpid(pid_t nr); 2018 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2019 struct pid_namespace *ns); 2020 2021 /* per-UID process charging. */ 2022 extern struct user_struct * alloc_uid(kuid_t); 2023 static inline struct user_struct *get_uid(struct user_struct *u) 2024 { 2025 atomic_inc(&u->__count); 2026 return u; 2027 } 2028 extern void free_uid(struct user_struct *); 2029 2030 #include <asm/current.h> 2031 2032 extern void xtime_update(unsigned long ticks); 2033 2034 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2035 extern int wake_up_process(struct task_struct *tsk); 2036 extern void wake_up_new_task(struct task_struct *tsk); 2037 #ifdef CONFIG_SMP 2038 extern void kick_process(struct task_struct *tsk); 2039 #else 2040 static inline void kick_process(struct task_struct *tsk) { } 2041 #endif 2042 extern void sched_fork(unsigned long clone_flags, struct task_struct *p); 2043 extern void sched_dead(struct task_struct *p); 2044 2045 extern void proc_caches_init(void); 2046 extern void flush_signals(struct task_struct *); 2047 extern void __flush_signals(struct task_struct *); 2048 extern void ignore_signals(struct task_struct *); 2049 extern void flush_signal_handlers(struct task_struct *, int force_default); 2050 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2051 2052 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2053 { 2054 unsigned long flags; 2055 int ret; 2056 2057 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2058 ret = dequeue_signal(tsk, mask, info); 2059 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2060 2061 return ret; 2062 } 2063 2064 extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2065 sigset_t *mask); 2066 extern void unblock_all_signals(void); 2067 extern void release_task(struct task_struct * p); 2068 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2069 extern int force_sigsegv(int, struct task_struct *); 2070 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2071 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2072 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2073 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2074 const struct cred *, u32); 2075 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2076 extern int kill_pid(struct pid *pid, int sig, int priv); 2077 extern int kill_proc_info(int, struct siginfo *, pid_t); 2078 extern __must_check bool do_notify_parent(struct task_struct *, int); 2079 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2080 extern void force_sig(int, struct task_struct *); 2081 extern int send_sig(int, struct task_struct *, int); 2082 extern int zap_other_threads(struct task_struct *p); 2083 extern struct sigqueue *sigqueue_alloc(void); 2084 extern void sigqueue_free(struct sigqueue *); 2085 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2086 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2087 2088 static inline void restore_saved_sigmask(void) 2089 { 2090 if (test_and_clear_restore_sigmask()) 2091 __set_current_blocked(¤t->saved_sigmask); 2092 } 2093 2094 static inline sigset_t *sigmask_to_save(void) 2095 { 2096 sigset_t *res = ¤t->blocked; 2097 if (unlikely(test_restore_sigmask())) 2098 res = ¤t->saved_sigmask; 2099 return res; 2100 } 2101 2102 static inline int kill_cad_pid(int sig, int priv) 2103 { 2104 return kill_pid(cad_pid, sig, priv); 2105 } 2106 2107 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2108 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2109 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2110 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2111 2112 /* 2113 * True if we are on the alternate signal stack. 2114 */ 2115 static inline int on_sig_stack(unsigned long sp) 2116 { 2117 #ifdef CONFIG_STACK_GROWSUP 2118 return sp >= current->sas_ss_sp && 2119 sp - current->sas_ss_sp < current->sas_ss_size; 2120 #else 2121 return sp > current->sas_ss_sp && 2122 sp - current->sas_ss_sp <= current->sas_ss_size; 2123 #endif 2124 } 2125 2126 static inline int sas_ss_flags(unsigned long sp) 2127 { 2128 return (current->sas_ss_size == 0 ? SS_DISABLE 2129 : on_sig_stack(sp) ? SS_ONSTACK : 0); 2130 } 2131 2132 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2133 { 2134 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2135 #ifdef CONFIG_STACK_GROWSUP 2136 return current->sas_ss_sp; 2137 #else 2138 return current->sas_ss_sp + current->sas_ss_size; 2139 #endif 2140 return sp; 2141 } 2142 2143 /* 2144 * Routines for handling mm_structs 2145 */ 2146 extern struct mm_struct * mm_alloc(void); 2147 2148 /* mmdrop drops the mm and the page tables */ 2149 extern void __mmdrop(struct mm_struct *); 2150 static inline void mmdrop(struct mm_struct * mm) 2151 { 2152 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2153 __mmdrop(mm); 2154 } 2155 2156 /* mmput gets rid of the mappings and all user-space */ 2157 extern void mmput(struct mm_struct *); 2158 /* Grab a reference to a task's mm, if it is not already going away */ 2159 extern struct mm_struct *get_task_mm(struct task_struct *task); 2160 /* 2161 * Grab a reference to a task's mm, if it is not already going away 2162 * and ptrace_may_access with the mode parameter passed to it 2163 * succeeds. 2164 */ 2165 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2166 /* Remove the current tasks stale references to the old mm_struct */ 2167 extern void mm_release(struct task_struct *, struct mm_struct *); 2168 /* Allocate a new mm structure and copy contents from tsk->mm */ 2169 extern struct mm_struct *dup_mm(struct task_struct *tsk); 2170 2171 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2172 struct task_struct *); 2173 extern void flush_thread(void); 2174 extern void exit_thread(void); 2175 2176 extern void exit_files(struct task_struct *); 2177 extern void __cleanup_sighand(struct sighand_struct *); 2178 2179 extern void exit_itimers(struct signal_struct *); 2180 extern void flush_itimer_signals(void); 2181 2182 extern void do_group_exit(int); 2183 2184 extern int allow_signal(int); 2185 extern int disallow_signal(int); 2186 2187 extern int do_execve(const char *, 2188 const char __user * const __user *, 2189 const char __user * const __user *); 2190 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2191 struct task_struct *fork_idle(int); 2192 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2193 2194 extern void set_task_comm(struct task_struct *tsk, char *from); 2195 extern char *get_task_comm(char *to, struct task_struct *tsk); 2196 2197 #ifdef CONFIG_SMP 2198 void scheduler_ipi(void); 2199 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2200 #else 2201 static inline void scheduler_ipi(void) { } 2202 static inline unsigned long wait_task_inactive(struct task_struct *p, 2203 long match_state) 2204 { 2205 return 1; 2206 } 2207 #endif 2208 2209 #define next_task(p) \ 2210 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2211 2212 #define for_each_process(p) \ 2213 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2214 2215 extern bool current_is_single_threaded(void); 2216 2217 /* 2218 * Careful: do_each_thread/while_each_thread is a double loop so 2219 * 'break' will not work as expected - use goto instead. 2220 */ 2221 #define do_each_thread(g, t) \ 2222 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2223 2224 #define while_each_thread(g, t) \ 2225 while ((t = next_thread(t)) != g) 2226 2227 static inline int get_nr_threads(struct task_struct *tsk) 2228 { 2229 return tsk->signal->nr_threads; 2230 } 2231 2232 static inline bool thread_group_leader(struct task_struct *p) 2233 { 2234 return p->exit_signal >= 0; 2235 } 2236 2237 /* Do to the insanities of de_thread it is possible for a process 2238 * to have the pid of the thread group leader without actually being 2239 * the thread group leader. For iteration through the pids in proc 2240 * all we care about is that we have a task with the appropriate 2241 * pid, we don't actually care if we have the right task. 2242 */ 2243 static inline bool has_group_leader_pid(struct task_struct *p) 2244 { 2245 return task_pid(p) == p->signal->leader_pid; 2246 } 2247 2248 static inline 2249 bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 2250 { 2251 return p1->signal == p2->signal; 2252 } 2253 2254 static inline struct task_struct *next_thread(const struct task_struct *p) 2255 { 2256 return list_entry_rcu(p->thread_group.next, 2257 struct task_struct, thread_group); 2258 } 2259 2260 static inline int thread_group_empty(struct task_struct *p) 2261 { 2262 return list_empty(&p->thread_group); 2263 } 2264 2265 #define delay_group_leader(p) \ 2266 (thread_group_leader(p) && !thread_group_empty(p)) 2267 2268 /* 2269 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2270 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2271 * pins the final release of task.io_context. Also protects ->cpuset and 2272 * ->cgroup.subsys[]. And ->vfork_done. 2273 * 2274 * Nests both inside and outside of read_lock(&tasklist_lock). 2275 * It must not be nested with write_lock_irq(&tasklist_lock), 2276 * neither inside nor outside. 2277 */ 2278 static inline void task_lock(struct task_struct *p) 2279 { 2280 spin_lock(&p->alloc_lock); 2281 } 2282 2283 static inline void task_unlock(struct task_struct *p) 2284 { 2285 spin_unlock(&p->alloc_lock); 2286 } 2287 2288 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2289 unsigned long *flags); 2290 2291 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2292 unsigned long *flags) 2293 { 2294 struct sighand_struct *ret; 2295 2296 ret = __lock_task_sighand(tsk, flags); 2297 (void)__cond_lock(&tsk->sighand->siglock, ret); 2298 return ret; 2299 } 2300 2301 static inline void unlock_task_sighand(struct task_struct *tsk, 2302 unsigned long *flags) 2303 { 2304 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2305 } 2306 2307 #ifdef CONFIG_CGROUPS 2308 static inline void threadgroup_change_begin(struct task_struct *tsk) 2309 { 2310 down_read(&tsk->signal->group_rwsem); 2311 } 2312 static inline void threadgroup_change_end(struct task_struct *tsk) 2313 { 2314 up_read(&tsk->signal->group_rwsem); 2315 } 2316 2317 /** 2318 * threadgroup_lock - lock threadgroup 2319 * @tsk: member task of the threadgroup to lock 2320 * 2321 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter 2322 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or 2323 * change ->group_leader/pid. This is useful for cases where the threadgroup 2324 * needs to stay stable across blockable operations. 2325 * 2326 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for 2327 * synchronization. While held, no new task will be added to threadgroup 2328 * and no existing live task will have its PF_EXITING set. 2329 * 2330 * de_thread() does threadgroup_change_{begin|end}() when a non-leader 2331 * sub-thread becomes a new leader. 2332 */ 2333 static inline void threadgroup_lock(struct task_struct *tsk) 2334 { 2335 down_write(&tsk->signal->group_rwsem); 2336 } 2337 2338 /** 2339 * threadgroup_unlock - unlock threadgroup 2340 * @tsk: member task of the threadgroup to unlock 2341 * 2342 * Reverse threadgroup_lock(). 2343 */ 2344 static inline void threadgroup_unlock(struct task_struct *tsk) 2345 { 2346 up_write(&tsk->signal->group_rwsem); 2347 } 2348 #else 2349 static inline void threadgroup_change_begin(struct task_struct *tsk) {} 2350 static inline void threadgroup_change_end(struct task_struct *tsk) {} 2351 static inline void threadgroup_lock(struct task_struct *tsk) {} 2352 static inline void threadgroup_unlock(struct task_struct *tsk) {} 2353 #endif 2354 2355 #ifndef __HAVE_THREAD_FUNCTIONS 2356 2357 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 2358 #define task_stack_page(task) ((task)->stack) 2359 2360 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2361 { 2362 *task_thread_info(p) = *task_thread_info(org); 2363 task_thread_info(p)->task = p; 2364 } 2365 2366 static inline unsigned long *end_of_stack(struct task_struct *p) 2367 { 2368 return (unsigned long *)(task_thread_info(p) + 1); 2369 } 2370 2371 #endif 2372 2373 static inline int object_is_on_stack(void *obj) 2374 { 2375 void *stack = task_stack_page(current); 2376 2377 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2378 } 2379 2380 extern void thread_info_cache_init(void); 2381 2382 #ifdef CONFIG_DEBUG_STACK_USAGE 2383 static inline unsigned long stack_not_used(struct task_struct *p) 2384 { 2385 unsigned long *n = end_of_stack(p); 2386 2387 do { /* Skip over canary */ 2388 n++; 2389 } while (!*n); 2390 2391 return (unsigned long)n - (unsigned long)end_of_stack(p); 2392 } 2393 #endif 2394 2395 /* set thread flags in other task's structures 2396 * - see asm/thread_info.h for TIF_xxxx flags available 2397 */ 2398 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2399 { 2400 set_ti_thread_flag(task_thread_info(tsk), flag); 2401 } 2402 2403 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2404 { 2405 clear_ti_thread_flag(task_thread_info(tsk), flag); 2406 } 2407 2408 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2409 { 2410 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2411 } 2412 2413 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2414 { 2415 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2416 } 2417 2418 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2419 { 2420 return test_ti_thread_flag(task_thread_info(tsk), flag); 2421 } 2422 2423 static inline void set_tsk_need_resched(struct task_struct *tsk) 2424 { 2425 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2426 } 2427 2428 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2429 { 2430 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2431 } 2432 2433 static inline int test_tsk_need_resched(struct task_struct *tsk) 2434 { 2435 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2436 } 2437 2438 static inline int restart_syscall(void) 2439 { 2440 set_tsk_thread_flag(current, TIF_SIGPENDING); 2441 return -ERESTARTNOINTR; 2442 } 2443 2444 static inline int signal_pending(struct task_struct *p) 2445 { 2446 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2447 } 2448 2449 static inline int __fatal_signal_pending(struct task_struct *p) 2450 { 2451 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2452 } 2453 2454 static inline int fatal_signal_pending(struct task_struct *p) 2455 { 2456 return signal_pending(p) && __fatal_signal_pending(p); 2457 } 2458 2459 static inline int signal_pending_state(long state, struct task_struct *p) 2460 { 2461 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2462 return 0; 2463 if (!signal_pending(p)) 2464 return 0; 2465 2466 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2467 } 2468 2469 /* 2470 * cond_resched() and cond_resched_lock(): latency reduction via 2471 * explicit rescheduling in places that are safe. The return 2472 * value indicates whether a reschedule was done in fact. 2473 * cond_resched_lock() will drop the spinlock before scheduling, 2474 * cond_resched_softirq() will enable bhs before scheduling. 2475 */ 2476 extern int _cond_resched(void); 2477 2478 #define cond_resched() ({ \ 2479 __might_sleep(__FILE__, __LINE__, 0); \ 2480 _cond_resched(); \ 2481 }) 2482 2483 extern int __cond_resched_lock(spinlock_t *lock); 2484 2485 #ifdef CONFIG_PREEMPT_COUNT 2486 #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2487 #else 2488 #define PREEMPT_LOCK_OFFSET 0 2489 #endif 2490 2491 #define cond_resched_lock(lock) ({ \ 2492 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2493 __cond_resched_lock(lock); \ 2494 }) 2495 2496 extern int __cond_resched_softirq(void); 2497 2498 #define cond_resched_softirq() ({ \ 2499 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2500 __cond_resched_softirq(); \ 2501 }) 2502 2503 static inline void cond_resched_rcu(void) 2504 { 2505 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 2506 rcu_read_unlock(); 2507 cond_resched(); 2508 rcu_read_lock(); 2509 #endif 2510 } 2511 2512 /* 2513 * Does a critical section need to be broken due to another 2514 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2515 * but a general need for low latency) 2516 */ 2517 static inline int spin_needbreak(spinlock_t *lock) 2518 { 2519 #ifdef CONFIG_PREEMPT 2520 return spin_is_contended(lock); 2521 #else 2522 return 0; 2523 #endif 2524 } 2525 2526 /* 2527 * Idle thread specific functions to determine the need_resched 2528 * polling state. We have two versions, one based on TS_POLLING in 2529 * thread_info.status and one based on TIF_POLLING_NRFLAG in 2530 * thread_info.flags 2531 */ 2532 #ifdef TS_POLLING 2533 static inline int tsk_is_polling(struct task_struct *p) 2534 { 2535 return task_thread_info(p)->status & TS_POLLING; 2536 } 2537 static inline void __current_set_polling(void) 2538 { 2539 current_thread_info()->status |= TS_POLLING; 2540 } 2541 2542 static inline bool __must_check current_set_polling_and_test(void) 2543 { 2544 __current_set_polling(); 2545 2546 /* 2547 * Polling state must be visible before we test NEED_RESCHED, 2548 * paired by resched_task() 2549 */ 2550 smp_mb(); 2551 2552 return unlikely(tif_need_resched()); 2553 } 2554 2555 static inline void __current_clr_polling(void) 2556 { 2557 current_thread_info()->status &= ~TS_POLLING; 2558 } 2559 2560 static inline bool __must_check current_clr_polling_and_test(void) 2561 { 2562 __current_clr_polling(); 2563 2564 /* 2565 * Polling state must be visible before we test NEED_RESCHED, 2566 * paired by resched_task() 2567 */ 2568 smp_mb(); 2569 2570 return unlikely(tif_need_resched()); 2571 } 2572 #elif defined(TIF_POLLING_NRFLAG) 2573 static inline int tsk_is_polling(struct task_struct *p) 2574 { 2575 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 2576 } 2577 2578 static inline void __current_set_polling(void) 2579 { 2580 set_thread_flag(TIF_POLLING_NRFLAG); 2581 } 2582 2583 static inline bool __must_check current_set_polling_and_test(void) 2584 { 2585 __current_set_polling(); 2586 2587 /* 2588 * Polling state must be visible before we test NEED_RESCHED, 2589 * paired by resched_task() 2590 * 2591 * XXX: assumes set/clear bit are identical barrier wise. 2592 */ 2593 smp_mb__after_clear_bit(); 2594 2595 return unlikely(tif_need_resched()); 2596 } 2597 2598 static inline void __current_clr_polling(void) 2599 { 2600 clear_thread_flag(TIF_POLLING_NRFLAG); 2601 } 2602 2603 static inline bool __must_check current_clr_polling_and_test(void) 2604 { 2605 __current_clr_polling(); 2606 2607 /* 2608 * Polling state must be visible before we test NEED_RESCHED, 2609 * paired by resched_task() 2610 */ 2611 smp_mb__after_clear_bit(); 2612 2613 return unlikely(tif_need_resched()); 2614 } 2615 2616 #else 2617 static inline int tsk_is_polling(struct task_struct *p) { return 0; } 2618 static inline void __current_set_polling(void) { } 2619 static inline void __current_clr_polling(void) { } 2620 2621 static inline bool __must_check current_set_polling_and_test(void) 2622 { 2623 return unlikely(tif_need_resched()); 2624 } 2625 static inline bool __must_check current_clr_polling_and_test(void) 2626 { 2627 return unlikely(tif_need_resched()); 2628 } 2629 #endif 2630 2631 static __always_inline bool need_resched(void) 2632 { 2633 return unlikely(tif_need_resched()); 2634 } 2635 2636 /* 2637 * Thread group CPU time accounting. 2638 */ 2639 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 2640 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 2641 2642 static inline void thread_group_cputime_init(struct signal_struct *sig) 2643 { 2644 raw_spin_lock_init(&sig->cputimer.lock); 2645 } 2646 2647 /* 2648 * Reevaluate whether the task has signals pending delivery. 2649 * Wake the task if so. 2650 * This is required every time the blocked sigset_t changes. 2651 * callers must hold sighand->siglock. 2652 */ 2653 extern void recalc_sigpending_and_wake(struct task_struct *t); 2654 extern void recalc_sigpending(void); 2655 2656 extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 2657 2658 static inline void signal_wake_up(struct task_struct *t, bool resume) 2659 { 2660 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 2661 } 2662 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 2663 { 2664 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 2665 } 2666 2667 /* 2668 * Wrappers for p->thread_info->cpu access. No-op on UP. 2669 */ 2670 #ifdef CONFIG_SMP 2671 2672 static inline unsigned int task_cpu(const struct task_struct *p) 2673 { 2674 return task_thread_info(p)->cpu; 2675 } 2676 2677 static inline int task_node(const struct task_struct *p) 2678 { 2679 return cpu_to_node(task_cpu(p)); 2680 } 2681 2682 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2683 2684 #else 2685 2686 static inline unsigned int task_cpu(const struct task_struct *p) 2687 { 2688 return 0; 2689 } 2690 2691 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2692 { 2693 } 2694 2695 #endif /* CONFIG_SMP */ 2696 2697 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2698 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2699 2700 #ifdef CONFIG_CGROUP_SCHED 2701 extern struct task_group root_task_group; 2702 #endif /* CONFIG_CGROUP_SCHED */ 2703 2704 extern int task_can_switch_user(struct user_struct *up, 2705 struct task_struct *tsk); 2706 2707 #ifdef CONFIG_TASK_XACCT 2708 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2709 { 2710 tsk->ioac.rchar += amt; 2711 } 2712 2713 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2714 { 2715 tsk->ioac.wchar += amt; 2716 } 2717 2718 static inline void inc_syscr(struct task_struct *tsk) 2719 { 2720 tsk->ioac.syscr++; 2721 } 2722 2723 static inline void inc_syscw(struct task_struct *tsk) 2724 { 2725 tsk->ioac.syscw++; 2726 } 2727 #else 2728 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2729 { 2730 } 2731 2732 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2733 { 2734 } 2735 2736 static inline void inc_syscr(struct task_struct *tsk) 2737 { 2738 } 2739 2740 static inline void inc_syscw(struct task_struct *tsk) 2741 { 2742 } 2743 #endif 2744 2745 #ifndef TASK_SIZE_OF 2746 #define TASK_SIZE_OF(tsk) TASK_SIZE 2747 #endif 2748 2749 #ifdef CONFIG_MM_OWNER 2750 extern void mm_update_next_owner(struct mm_struct *mm); 2751 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); 2752 #else 2753 static inline void mm_update_next_owner(struct mm_struct *mm) 2754 { 2755 } 2756 2757 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) 2758 { 2759 } 2760 #endif /* CONFIG_MM_OWNER */ 2761 2762 static inline unsigned long task_rlimit(const struct task_struct *tsk, 2763 unsigned int limit) 2764 { 2765 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); 2766 } 2767 2768 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 2769 unsigned int limit) 2770 { 2771 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); 2772 } 2773 2774 static inline unsigned long rlimit(unsigned int limit) 2775 { 2776 return task_rlimit(current, limit); 2777 } 2778 2779 static inline unsigned long rlimit_max(unsigned int limit) 2780 { 2781 return task_rlimit_max(current, limit); 2782 } 2783 2784 #endif 2785