1 #ifndef _LINUX_SCHED_H 2 #define _LINUX_SCHED_H 3 4 /* 5 * cloning flags: 6 */ 7 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */ 8 #define CLONE_VM 0x00000100 /* set if VM shared between processes */ 9 #define CLONE_FS 0x00000200 /* set if fs info shared between processes */ 10 #define CLONE_FILES 0x00000400 /* set if open files shared between processes */ 11 #define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */ 12 #define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */ 13 #define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */ 14 #define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */ 15 #define CLONE_THREAD 0x00010000 /* Same thread group? */ 16 #define CLONE_NEWNS 0x00020000 /* New namespace group? */ 17 #define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */ 18 #define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */ 19 #define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */ 20 #define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */ 21 #define CLONE_DETACHED 0x00400000 /* Unused, ignored */ 22 #define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */ 23 #define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */ 24 /* 0x02000000 was previously the unused CLONE_STOPPED (Start in stopped state) 25 and is now available for re-use. */ 26 #define CLONE_NEWUTS 0x04000000 /* New utsname group? */ 27 #define CLONE_NEWIPC 0x08000000 /* New ipcs */ 28 #define CLONE_NEWUSER 0x10000000 /* New user namespace */ 29 #define CLONE_NEWPID 0x20000000 /* New pid namespace */ 30 #define CLONE_NEWNET 0x40000000 /* New network namespace */ 31 #define CLONE_IO 0x80000000 /* Clone io context */ 32 33 /* 34 * Scheduling policies 35 */ 36 #define SCHED_NORMAL 0 37 #define SCHED_FIFO 1 38 #define SCHED_RR 2 39 #define SCHED_BATCH 3 40 /* SCHED_ISO: reserved but not implemented yet */ 41 #define SCHED_IDLE 5 42 /* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */ 43 #define SCHED_RESET_ON_FORK 0x40000000 44 45 #ifdef __KERNEL__ 46 47 struct sched_param { 48 int sched_priority; 49 }; 50 51 #include <asm/param.h> /* for HZ */ 52 53 #include <linux/capability.h> 54 #include <linux/threads.h> 55 #include <linux/kernel.h> 56 #include <linux/types.h> 57 #include <linux/timex.h> 58 #include <linux/jiffies.h> 59 #include <linux/rbtree.h> 60 #include <linux/thread_info.h> 61 #include <linux/cpumask.h> 62 #include <linux/errno.h> 63 #include <linux/nodemask.h> 64 #include <linux/mm_types.h> 65 66 #include <asm/page.h> 67 #include <asm/ptrace.h> 68 #include <asm/cputime.h> 69 70 #include <linux/smp.h> 71 #include <linux/sem.h> 72 #include <linux/signal.h> 73 #include <linux/compiler.h> 74 #include <linux/completion.h> 75 #include <linux/pid.h> 76 #include <linux/percpu.h> 77 #include <linux/topology.h> 78 #include <linux/proportions.h> 79 #include <linux/seccomp.h> 80 #include <linux/rcupdate.h> 81 #include <linux/rculist.h> 82 #include <linux/rtmutex.h> 83 84 #include <linux/time.h> 85 #include <linux/param.h> 86 #include <linux/resource.h> 87 #include <linux/timer.h> 88 #include <linux/hrtimer.h> 89 #include <linux/task_io_accounting.h> 90 #include <linux/latencytop.h> 91 #include <linux/cred.h> 92 #include <linux/llist.h> 93 94 #include <asm/processor.h> 95 96 struct exec_domain; 97 struct futex_pi_state; 98 struct robust_list_head; 99 struct bio_list; 100 struct fs_struct; 101 struct perf_event_context; 102 struct blk_plug; 103 104 /* 105 * List of flags we want to share for kernel threads, 106 * if only because they are not used by them anyway. 107 */ 108 #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND) 109 110 /* 111 * These are the constant used to fake the fixed-point load-average 112 * counting. Some notes: 113 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 114 * a load-average precision of 10 bits integer + 11 bits fractional 115 * - if you want to count load-averages more often, you need more 116 * precision, or rounding will get you. With 2-second counting freq, 117 * the EXP_n values would be 1981, 2034 and 2043 if still using only 118 * 11 bit fractions. 119 */ 120 extern unsigned long avenrun[]; /* Load averages */ 121 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 122 123 #define FSHIFT 11 /* nr of bits of precision */ 124 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 125 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 126 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 127 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 128 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 129 130 #define CALC_LOAD(load,exp,n) \ 131 load *= exp; \ 132 load += n*(FIXED_1-exp); \ 133 load >>= FSHIFT; 134 135 extern unsigned long total_forks; 136 extern int nr_threads; 137 DECLARE_PER_CPU(unsigned long, process_counts); 138 extern int nr_processes(void); 139 extern unsigned long nr_running(void); 140 extern unsigned long nr_uninterruptible(void); 141 extern unsigned long nr_iowait(void); 142 extern unsigned long nr_iowait_cpu(int cpu); 143 extern unsigned long this_cpu_load(void); 144 145 146 extern void calc_global_load(unsigned long ticks); 147 148 extern unsigned long get_parent_ip(unsigned long addr); 149 150 struct seq_file; 151 struct cfs_rq; 152 struct task_group; 153 #ifdef CONFIG_SCHED_DEBUG 154 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 155 extern void proc_sched_set_task(struct task_struct *p); 156 extern void 157 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 158 #else 159 static inline void 160 proc_sched_show_task(struct task_struct *p, struct seq_file *m) 161 { 162 } 163 static inline void proc_sched_set_task(struct task_struct *p) 164 { 165 } 166 static inline void 167 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) 168 { 169 } 170 #endif 171 172 /* 173 * Task state bitmask. NOTE! These bits are also 174 * encoded in fs/proc/array.c: get_task_state(). 175 * 176 * We have two separate sets of flags: task->state 177 * is about runnability, while task->exit_state are 178 * about the task exiting. Confusing, but this way 179 * modifying one set can't modify the other one by 180 * mistake. 181 */ 182 #define TASK_RUNNING 0 183 #define TASK_INTERRUPTIBLE 1 184 #define TASK_UNINTERRUPTIBLE 2 185 #define __TASK_STOPPED 4 186 #define __TASK_TRACED 8 187 /* in tsk->exit_state */ 188 #define EXIT_ZOMBIE 16 189 #define EXIT_DEAD 32 190 /* in tsk->state again */ 191 #define TASK_DEAD 64 192 #define TASK_WAKEKILL 128 193 #define TASK_WAKING 256 194 #define TASK_STATE_MAX 512 195 196 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW" 197 198 extern char ___assert_task_state[1 - 2*!!( 199 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 200 201 /* Convenience macros for the sake of set_task_state */ 202 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 203 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 204 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 205 206 /* Convenience macros for the sake of wake_up */ 207 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 208 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 209 210 /* get_task_state() */ 211 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 212 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 213 __TASK_TRACED) 214 215 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 216 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 217 #define task_is_dead(task) ((task)->exit_state != 0) 218 #define task_is_stopped_or_traced(task) \ 219 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 220 #define task_contributes_to_load(task) \ 221 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 222 (task->flags & PF_FROZEN) == 0) 223 224 #define __set_task_state(tsk, state_value) \ 225 do { (tsk)->state = (state_value); } while (0) 226 #define set_task_state(tsk, state_value) \ 227 set_mb((tsk)->state, (state_value)) 228 229 /* 230 * set_current_state() includes a barrier so that the write of current->state 231 * is correctly serialised wrt the caller's subsequent test of whether to 232 * actually sleep: 233 * 234 * set_current_state(TASK_UNINTERRUPTIBLE); 235 * if (do_i_need_to_sleep()) 236 * schedule(); 237 * 238 * If the caller does not need such serialisation then use __set_current_state() 239 */ 240 #define __set_current_state(state_value) \ 241 do { current->state = (state_value); } while (0) 242 #define set_current_state(state_value) \ 243 set_mb(current->state, (state_value)) 244 245 /* Task command name length */ 246 #define TASK_COMM_LEN 16 247 248 #include <linux/spinlock.h> 249 250 /* 251 * This serializes "schedule()" and also protects 252 * the run-queue from deletions/modifications (but 253 * _adding_ to the beginning of the run-queue has 254 * a separate lock). 255 */ 256 extern rwlock_t tasklist_lock; 257 extern spinlock_t mmlist_lock; 258 259 struct task_struct; 260 261 #ifdef CONFIG_PROVE_RCU 262 extern int lockdep_tasklist_lock_is_held(void); 263 #endif /* #ifdef CONFIG_PROVE_RCU */ 264 265 extern void sched_init(void); 266 extern void sched_init_smp(void); 267 extern asmlinkage void schedule_tail(struct task_struct *prev); 268 extern void init_idle(struct task_struct *idle, int cpu); 269 extern void init_idle_bootup_task(struct task_struct *idle); 270 271 extern int runqueue_is_locked(int cpu); 272 273 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ) 274 extern void select_nohz_load_balancer(int stop_tick); 275 extern void set_cpu_sd_state_idle(void); 276 extern int get_nohz_timer_target(void); 277 #else 278 static inline void select_nohz_load_balancer(int stop_tick) { } 279 static inline void set_cpu_sd_state_idle(void) { } 280 #endif 281 282 /* 283 * Only dump TASK_* tasks. (0 for all tasks) 284 */ 285 extern void show_state_filter(unsigned long state_filter); 286 287 static inline void show_state(void) 288 { 289 show_state_filter(0); 290 } 291 292 extern void show_regs(struct pt_regs *); 293 294 /* 295 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 296 * task), SP is the stack pointer of the first frame that should be shown in the back 297 * trace (or NULL if the entire call-chain of the task should be shown). 298 */ 299 extern void show_stack(struct task_struct *task, unsigned long *sp); 300 301 void io_schedule(void); 302 long io_schedule_timeout(long timeout); 303 304 extern void cpu_init (void); 305 extern void trap_init(void); 306 extern void update_process_times(int user); 307 extern void scheduler_tick(void); 308 309 extern void sched_show_task(struct task_struct *p); 310 311 #ifdef CONFIG_LOCKUP_DETECTOR 312 extern void touch_softlockup_watchdog(void); 313 extern void touch_softlockup_watchdog_sync(void); 314 extern void touch_all_softlockup_watchdogs(void); 315 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 316 void __user *buffer, 317 size_t *lenp, loff_t *ppos); 318 extern unsigned int softlockup_panic; 319 void lockup_detector_init(void); 320 #else 321 static inline void touch_softlockup_watchdog(void) 322 { 323 } 324 static inline void touch_softlockup_watchdog_sync(void) 325 { 326 } 327 static inline void touch_all_softlockup_watchdogs(void) 328 { 329 } 330 static inline void lockup_detector_init(void) 331 { 332 } 333 #endif 334 335 #ifdef CONFIG_DETECT_HUNG_TASK 336 extern unsigned int sysctl_hung_task_panic; 337 extern unsigned long sysctl_hung_task_check_count; 338 extern unsigned long sysctl_hung_task_timeout_secs; 339 extern unsigned long sysctl_hung_task_warnings; 340 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, 341 void __user *buffer, 342 size_t *lenp, loff_t *ppos); 343 #else 344 /* Avoid need for ifdefs elsewhere in the code */ 345 enum { sysctl_hung_task_timeout_secs = 0 }; 346 #endif 347 348 /* Attach to any functions which should be ignored in wchan output. */ 349 #define __sched __attribute__((__section__(".sched.text"))) 350 351 /* Linker adds these: start and end of __sched functions */ 352 extern char __sched_text_start[], __sched_text_end[]; 353 354 /* Is this address in the __sched functions? */ 355 extern int in_sched_functions(unsigned long addr); 356 357 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 358 extern signed long schedule_timeout(signed long timeout); 359 extern signed long schedule_timeout_interruptible(signed long timeout); 360 extern signed long schedule_timeout_killable(signed long timeout); 361 extern signed long schedule_timeout_uninterruptible(signed long timeout); 362 asmlinkage void schedule(void); 363 extern void schedule_preempt_disabled(void); 364 extern int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner); 365 366 struct nsproxy; 367 struct user_namespace; 368 369 /* 370 * Default maximum number of active map areas, this limits the number of vmas 371 * per mm struct. Users can overwrite this number by sysctl but there is a 372 * problem. 373 * 374 * When a program's coredump is generated as ELF format, a section is created 375 * per a vma. In ELF, the number of sections is represented in unsigned short. 376 * This means the number of sections should be smaller than 65535 at coredump. 377 * Because the kernel adds some informative sections to a image of program at 378 * generating coredump, we need some margin. The number of extra sections is 379 * 1-3 now and depends on arch. We use "5" as safe margin, here. 380 */ 381 #define MAPCOUNT_ELF_CORE_MARGIN (5) 382 #define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) 383 384 extern int sysctl_max_map_count; 385 386 #include <linux/aio.h> 387 388 #ifdef CONFIG_MMU 389 extern void arch_pick_mmap_layout(struct mm_struct *mm); 390 extern unsigned long 391 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 392 unsigned long, unsigned long); 393 extern unsigned long 394 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 395 unsigned long len, unsigned long pgoff, 396 unsigned long flags); 397 extern void arch_unmap_area(struct mm_struct *, unsigned long); 398 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); 399 #else 400 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 401 #endif 402 403 404 extern void set_dumpable(struct mm_struct *mm, int value); 405 extern int get_dumpable(struct mm_struct *mm); 406 407 /* mm flags */ 408 /* dumpable bits */ 409 #define MMF_DUMPABLE 0 /* core dump is permitted */ 410 #define MMF_DUMP_SECURELY 1 /* core file is readable only by root */ 411 412 #define MMF_DUMPABLE_BITS 2 413 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 414 415 /* coredump filter bits */ 416 #define MMF_DUMP_ANON_PRIVATE 2 417 #define MMF_DUMP_ANON_SHARED 3 418 #define MMF_DUMP_MAPPED_PRIVATE 4 419 #define MMF_DUMP_MAPPED_SHARED 5 420 #define MMF_DUMP_ELF_HEADERS 6 421 #define MMF_DUMP_HUGETLB_PRIVATE 7 422 #define MMF_DUMP_HUGETLB_SHARED 8 423 424 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 425 #define MMF_DUMP_FILTER_BITS 7 426 #define MMF_DUMP_FILTER_MASK \ 427 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 428 #define MMF_DUMP_FILTER_DEFAULT \ 429 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 430 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 431 432 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 433 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 434 #else 435 # define MMF_DUMP_MASK_DEFAULT_ELF 0 436 #endif 437 /* leave room for more dump flags */ 438 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 439 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 440 441 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 442 443 struct sighand_struct { 444 atomic_t count; 445 struct k_sigaction action[_NSIG]; 446 spinlock_t siglock; 447 wait_queue_head_t signalfd_wqh; 448 }; 449 450 struct pacct_struct { 451 int ac_flag; 452 long ac_exitcode; 453 unsigned long ac_mem; 454 cputime_t ac_utime, ac_stime; 455 unsigned long ac_minflt, ac_majflt; 456 }; 457 458 struct cpu_itimer { 459 cputime_t expires; 460 cputime_t incr; 461 u32 error; 462 u32 incr_error; 463 }; 464 465 /** 466 * struct task_cputime - collected CPU time counts 467 * @utime: time spent in user mode, in &cputime_t units 468 * @stime: time spent in kernel mode, in &cputime_t units 469 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 470 * 471 * This structure groups together three kinds of CPU time that are 472 * tracked for threads and thread groups. Most things considering 473 * CPU time want to group these counts together and treat all three 474 * of them in parallel. 475 */ 476 struct task_cputime { 477 cputime_t utime; 478 cputime_t stime; 479 unsigned long long sum_exec_runtime; 480 }; 481 /* Alternate field names when used to cache expirations. */ 482 #define prof_exp stime 483 #define virt_exp utime 484 #define sched_exp sum_exec_runtime 485 486 #define INIT_CPUTIME \ 487 (struct task_cputime) { \ 488 .utime = 0, \ 489 .stime = 0, \ 490 .sum_exec_runtime = 0, \ 491 } 492 493 /* 494 * Disable preemption until the scheduler is running. 495 * Reset by start_kernel()->sched_init()->init_idle(). 496 * 497 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 498 * before the scheduler is active -- see should_resched(). 499 */ 500 #define INIT_PREEMPT_COUNT (1 + PREEMPT_ACTIVE) 501 502 /** 503 * struct thread_group_cputimer - thread group interval timer counts 504 * @cputime: thread group interval timers. 505 * @running: non-zero when there are timers running and 506 * @cputime receives updates. 507 * @lock: lock for fields in this struct. 508 * 509 * This structure contains the version of task_cputime, above, that is 510 * used for thread group CPU timer calculations. 511 */ 512 struct thread_group_cputimer { 513 struct task_cputime cputime; 514 int running; 515 raw_spinlock_t lock; 516 }; 517 518 #include <linux/rwsem.h> 519 struct autogroup; 520 521 /* 522 * NOTE! "signal_struct" does not have its own 523 * locking, because a shared signal_struct always 524 * implies a shared sighand_struct, so locking 525 * sighand_struct is always a proper superset of 526 * the locking of signal_struct. 527 */ 528 struct signal_struct { 529 atomic_t sigcnt; 530 atomic_t live; 531 int nr_threads; 532 533 wait_queue_head_t wait_chldexit; /* for wait4() */ 534 535 /* current thread group signal load-balancing target: */ 536 struct task_struct *curr_target; 537 538 /* shared signal handling: */ 539 struct sigpending shared_pending; 540 541 /* thread group exit support */ 542 int group_exit_code; 543 /* overloaded: 544 * - notify group_exit_task when ->count is equal to notify_count 545 * - everyone except group_exit_task is stopped during signal delivery 546 * of fatal signals, group_exit_task processes the signal. 547 */ 548 int notify_count; 549 struct task_struct *group_exit_task; 550 551 /* thread group stop support, overloads group_exit_code too */ 552 int group_stop_count; 553 unsigned int flags; /* see SIGNAL_* flags below */ 554 555 /* 556 * PR_SET_CHILD_SUBREAPER marks a process, like a service 557 * manager, to re-parent orphan (double-forking) child processes 558 * to this process instead of 'init'. The service manager is 559 * able to receive SIGCHLD signals and is able to investigate 560 * the process until it calls wait(). All children of this 561 * process will inherit a flag if they should look for a 562 * child_subreaper process at exit. 563 */ 564 unsigned int is_child_subreaper:1; 565 unsigned int has_child_subreaper:1; 566 567 /* POSIX.1b Interval Timers */ 568 struct list_head posix_timers; 569 570 /* ITIMER_REAL timer for the process */ 571 struct hrtimer real_timer; 572 struct pid *leader_pid; 573 ktime_t it_real_incr; 574 575 /* 576 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 577 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 578 * values are defined to 0 and 1 respectively 579 */ 580 struct cpu_itimer it[2]; 581 582 /* 583 * Thread group totals for process CPU timers. 584 * See thread_group_cputimer(), et al, for details. 585 */ 586 struct thread_group_cputimer cputimer; 587 588 /* Earliest-expiration cache. */ 589 struct task_cputime cputime_expires; 590 591 struct list_head cpu_timers[3]; 592 593 struct pid *tty_old_pgrp; 594 595 /* boolean value for session group leader */ 596 int leader; 597 598 struct tty_struct *tty; /* NULL if no tty */ 599 600 #ifdef CONFIG_SCHED_AUTOGROUP 601 struct autogroup *autogroup; 602 #endif 603 /* 604 * Cumulative resource counters for dead threads in the group, 605 * and for reaped dead child processes forked by this group. 606 * Live threads maintain their own counters and add to these 607 * in __exit_signal, except for the group leader. 608 */ 609 cputime_t utime, stime, cutime, cstime; 610 cputime_t gtime; 611 cputime_t cgtime; 612 #ifndef CONFIG_VIRT_CPU_ACCOUNTING 613 cputime_t prev_utime, prev_stime; 614 #endif 615 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 616 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 617 unsigned long inblock, oublock, cinblock, coublock; 618 unsigned long maxrss, cmaxrss; 619 struct task_io_accounting ioac; 620 621 /* 622 * Cumulative ns of schedule CPU time fo dead threads in the 623 * group, not including a zombie group leader, (This only differs 624 * from jiffies_to_ns(utime + stime) if sched_clock uses something 625 * other than jiffies.) 626 */ 627 unsigned long long sum_sched_runtime; 628 629 /* 630 * We don't bother to synchronize most readers of this at all, 631 * because there is no reader checking a limit that actually needs 632 * to get both rlim_cur and rlim_max atomically, and either one 633 * alone is a single word that can safely be read normally. 634 * getrlimit/setrlimit use task_lock(current->group_leader) to 635 * protect this instead of the siglock, because they really 636 * have no need to disable irqs. 637 */ 638 struct rlimit rlim[RLIM_NLIMITS]; 639 640 #ifdef CONFIG_BSD_PROCESS_ACCT 641 struct pacct_struct pacct; /* per-process accounting information */ 642 #endif 643 #ifdef CONFIG_TASKSTATS 644 struct taskstats *stats; 645 #endif 646 #ifdef CONFIG_AUDIT 647 unsigned audit_tty; 648 struct tty_audit_buf *tty_audit_buf; 649 #endif 650 #ifdef CONFIG_CGROUPS 651 /* 652 * group_rwsem prevents new tasks from entering the threadgroup and 653 * member tasks from exiting,a more specifically, setting of 654 * PF_EXITING. fork and exit paths are protected with this rwsem 655 * using threadgroup_change_begin/end(). Users which require 656 * threadgroup to remain stable should use threadgroup_[un]lock() 657 * which also takes care of exec path. Currently, cgroup is the 658 * only user. 659 */ 660 struct rw_semaphore group_rwsem; 661 #endif 662 663 int oom_adj; /* OOM kill score adjustment (bit shift) */ 664 int oom_score_adj; /* OOM kill score adjustment */ 665 int oom_score_adj_min; /* OOM kill score adjustment minimum value. 666 * Only settable by CAP_SYS_RESOURCE. */ 667 668 struct mutex cred_guard_mutex; /* guard against foreign influences on 669 * credential calculations 670 * (notably. ptrace) */ 671 }; 672 673 /* Context switch must be unlocked if interrupts are to be enabled */ 674 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW 675 # define __ARCH_WANT_UNLOCKED_CTXSW 676 #endif 677 678 /* 679 * Bits in flags field of signal_struct. 680 */ 681 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 682 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 683 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 684 /* 685 * Pending notifications to parent. 686 */ 687 #define SIGNAL_CLD_STOPPED 0x00000010 688 #define SIGNAL_CLD_CONTINUED 0x00000020 689 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 690 691 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 692 693 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 694 static inline int signal_group_exit(const struct signal_struct *sig) 695 { 696 return (sig->flags & SIGNAL_GROUP_EXIT) || 697 (sig->group_exit_task != NULL); 698 } 699 700 /* 701 * Some day this will be a full-fledged user tracking system.. 702 */ 703 struct user_struct { 704 atomic_t __count; /* reference count */ 705 atomic_t processes; /* How many processes does this user have? */ 706 atomic_t files; /* How many open files does this user have? */ 707 atomic_t sigpending; /* How many pending signals does this user have? */ 708 #ifdef CONFIG_INOTIFY_USER 709 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 710 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 711 #endif 712 #ifdef CONFIG_FANOTIFY 713 atomic_t fanotify_listeners; 714 #endif 715 #ifdef CONFIG_EPOLL 716 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 717 #endif 718 #ifdef CONFIG_POSIX_MQUEUE 719 /* protected by mq_lock */ 720 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 721 #endif 722 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 723 724 #ifdef CONFIG_KEYS 725 struct key *uid_keyring; /* UID specific keyring */ 726 struct key *session_keyring; /* UID's default session keyring */ 727 #endif 728 729 /* Hash table maintenance information */ 730 struct hlist_node uidhash_node; 731 uid_t uid; 732 struct user_namespace *user_ns; 733 734 #ifdef CONFIG_PERF_EVENTS 735 atomic_long_t locked_vm; 736 #endif 737 }; 738 739 extern int uids_sysfs_init(void); 740 741 extern struct user_struct *find_user(uid_t); 742 743 extern struct user_struct root_user; 744 #define INIT_USER (&root_user) 745 746 747 struct backing_dev_info; 748 struct reclaim_state; 749 750 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 751 struct sched_info { 752 /* cumulative counters */ 753 unsigned long pcount; /* # of times run on this cpu */ 754 unsigned long long run_delay; /* time spent waiting on a runqueue */ 755 756 /* timestamps */ 757 unsigned long long last_arrival,/* when we last ran on a cpu */ 758 last_queued; /* when we were last queued to run */ 759 }; 760 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ 761 762 #ifdef CONFIG_TASK_DELAY_ACCT 763 struct task_delay_info { 764 spinlock_t lock; 765 unsigned int flags; /* Private per-task flags */ 766 767 /* For each stat XXX, add following, aligned appropriately 768 * 769 * struct timespec XXX_start, XXX_end; 770 * u64 XXX_delay; 771 * u32 XXX_count; 772 * 773 * Atomicity of updates to XXX_delay, XXX_count protected by 774 * single lock above (split into XXX_lock if contention is an issue). 775 */ 776 777 /* 778 * XXX_count is incremented on every XXX operation, the delay 779 * associated with the operation is added to XXX_delay. 780 * XXX_delay contains the accumulated delay time in nanoseconds. 781 */ 782 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ 783 u64 blkio_delay; /* wait for sync block io completion */ 784 u64 swapin_delay; /* wait for swapin block io completion */ 785 u32 blkio_count; /* total count of the number of sync block */ 786 /* io operations performed */ 787 u32 swapin_count; /* total count of the number of swapin block */ 788 /* io operations performed */ 789 790 struct timespec freepages_start, freepages_end; 791 u64 freepages_delay; /* wait for memory reclaim */ 792 u32 freepages_count; /* total count of memory reclaim */ 793 }; 794 #endif /* CONFIG_TASK_DELAY_ACCT */ 795 796 static inline int sched_info_on(void) 797 { 798 #ifdef CONFIG_SCHEDSTATS 799 return 1; 800 #elif defined(CONFIG_TASK_DELAY_ACCT) 801 extern int delayacct_on; 802 return delayacct_on; 803 #else 804 return 0; 805 #endif 806 } 807 808 enum cpu_idle_type { 809 CPU_IDLE, 810 CPU_NOT_IDLE, 811 CPU_NEWLY_IDLE, 812 CPU_MAX_IDLE_TYPES 813 }; 814 815 /* 816 * Increase resolution of nice-level calculations for 64-bit architectures. 817 * The extra resolution improves shares distribution and load balancing of 818 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 819 * hierarchies, especially on larger systems. This is not a user-visible change 820 * and does not change the user-interface for setting shares/weights. 821 * 822 * We increase resolution only if we have enough bits to allow this increased 823 * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution 824 * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the 825 * increased costs. 826 */ 827 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */ 828 # define SCHED_LOAD_RESOLUTION 10 829 # define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION) 830 # define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION) 831 #else 832 # define SCHED_LOAD_RESOLUTION 0 833 # define scale_load(w) (w) 834 # define scale_load_down(w) (w) 835 #endif 836 837 #define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION) 838 #define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT) 839 840 /* 841 * Increase resolution of cpu_power calculations 842 */ 843 #define SCHED_POWER_SHIFT 10 844 #define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT) 845 846 /* 847 * sched-domains (multiprocessor balancing) declarations: 848 */ 849 #ifdef CONFIG_SMP 850 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 851 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 852 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 853 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 854 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 855 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 856 #define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */ 857 #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ 858 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 859 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 860 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 861 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 862 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 863 864 extern int __weak arch_sd_sibiling_asym_packing(void); 865 866 struct sched_group_power { 867 atomic_t ref; 868 /* 869 * CPU power of this group, SCHED_LOAD_SCALE being max power for a 870 * single CPU. 871 */ 872 unsigned int power, power_orig; 873 unsigned long next_update; 874 /* 875 * Number of busy cpus in this group. 876 */ 877 atomic_t nr_busy_cpus; 878 }; 879 880 struct sched_group { 881 struct sched_group *next; /* Must be a circular list */ 882 atomic_t ref; 883 884 unsigned int group_weight; 885 struct sched_group_power *sgp; 886 887 /* 888 * The CPUs this group covers. 889 * 890 * NOTE: this field is variable length. (Allocated dynamically 891 * by attaching extra space to the end of the structure, 892 * depending on how many CPUs the kernel has booted up with) 893 */ 894 unsigned long cpumask[0]; 895 }; 896 897 static inline struct cpumask *sched_group_cpus(struct sched_group *sg) 898 { 899 return to_cpumask(sg->cpumask); 900 } 901 902 /** 903 * group_first_cpu - Returns the first cpu in the cpumask of a sched_group. 904 * @group: The group whose first cpu is to be returned. 905 */ 906 static inline unsigned int group_first_cpu(struct sched_group *group) 907 { 908 return cpumask_first(sched_group_cpus(group)); 909 } 910 911 struct sched_domain_attr { 912 int relax_domain_level; 913 }; 914 915 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 916 .relax_domain_level = -1, \ 917 } 918 919 extern int sched_domain_level_max; 920 921 struct sched_domain { 922 /* These fields must be setup */ 923 struct sched_domain *parent; /* top domain must be null terminated */ 924 struct sched_domain *child; /* bottom domain must be null terminated */ 925 struct sched_group *groups; /* the balancing groups of the domain */ 926 unsigned long min_interval; /* Minimum balance interval ms */ 927 unsigned long max_interval; /* Maximum balance interval ms */ 928 unsigned int busy_factor; /* less balancing by factor if busy */ 929 unsigned int imbalance_pct; /* No balance until over watermark */ 930 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 931 unsigned int busy_idx; 932 unsigned int idle_idx; 933 unsigned int newidle_idx; 934 unsigned int wake_idx; 935 unsigned int forkexec_idx; 936 unsigned int smt_gain; 937 int flags; /* See SD_* */ 938 int level; 939 940 /* Runtime fields. */ 941 unsigned long last_balance; /* init to jiffies. units in jiffies */ 942 unsigned int balance_interval; /* initialise to 1. units in ms. */ 943 unsigned int nr_balance_failed; /* initialise to 0 */ 944 945 u64 last_update; 946 947 #ifdef CONFIG_SCHEDSTATS 948 /* load_balance() stats */ 949 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 950 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 951 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 952 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 953 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 954 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 955 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 956 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 957 958 /* Active load balancing */ 959 unsigned int alb_count; 960 unsigned int alb_failed; 961 unsigned int alb_pushed; 962 963 /* SD_BALANCE_EXEC stats */ 964 unsigned int sbe_count; 965 unsigned int sbe_balanced; 966 unsigned int sbe_pushed; 967 968 /* SD_BALANCE_FORK stats */ 969 unsigned int sbf_count; 970 unsigned int sbf_balanced; 971 unsigned int sbf_pushed; 972 973 /* try_to_wake_up() stats */ 974 unsigned int ttwu_wake_remote; 975 unsigned int ttwu_move_affine; 976 unsigned int ttwu_move_balance; 977 #endif 978 #ifdef CONFIG_SCHED_DEBUG 979 char *name; 980 #endif 981 union { 982 void *private; /* used during construction */ 983 struct rcu_head rcu; /* used during destruction */ 984 }; 985 986 unsigned int span_weight; 987 /* 988 * Span of all CPUs in this domain. 989 * 990 * NOTE: this field is variable length. (Allocated dynamically 991 * by attaching extra space to the end of the structure, 992 * depending on how many CPUs the kernel has booted up with) 993 */ 994 unsigned long span[0]; 995 }; 996 997 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 998 { 999 return to_cpumask(sd->span); 1000 } 1001 1002 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1003 struct sched_domain_attr *dattr_new); 1004 1005 /* Allocate an array of sched domains, for partition_sched_domains(). */ 1006 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 1007 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 1008 1009 /* Test a flag in parent sched domain */ 1010 static inline int test_sd_parent(struct sched_domain *sd, int flag) 1011 { 1012 if (sd->parent && (sd->parent->flags & flag)) 1013 return 1; 1014 1015 return 0; 1016 } 1017 1018 unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu); 1019 unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu); 1020 1021 bool cpus_share_cache(int this_cpu, int that_cpu); 1022 1023 #else /* CONFIG_SMP */ 1024 1025 struct sched_domain_attr; 1026 1027 static inline void 1028 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1029 struct sched_domain_attr *dattr_new) 1030 { 1031 } 1032 1033 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1034 { 1035 return true; 1036 } 1037 1038 #endif /* !CONFIG_SMP */ 1039 1040 1041 struct io_context; /* See blkdev.h */ 1042 1043 1044 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1045 extern void prefetch_stack(struct task_struct *t); 1046 #else 1047 static inline void prefetch_stack(struct task_struct *t) { } 1048 #endif 1049 1050 struct audit_context; /* See audit.c */ 1051 struct mempolicy; 1052 struct pipe_inode_info; 1053 struct uts_namespace; 1054 1055 struct rq; 1056 struct sched_domain; 1057 1058 /* 1059 * wake flags 1060 */ 1061 #define WF_SYNC 0x01 /* waker goes to sleep after wakup */ 1062 #define WF_FORK 0x02 /* child wakeup after fork */ 1063 #define WF_MIGRATED 0x04 /* internal use, task got migrated */ 1064 1065 #define ENQUEUE_WAKEUP 1 1066 #define ENQUEUE_HEAD 2 1067 #ifdef CONFIG_SMP 1068 #define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */ 1069 #else 1070 #define ENQUEUE_WAKING 0 1071 #endif 1072 1073 #define DEQUEUE_SLEEP 1 1074 1075 struct sched_class { 1076 const struct sched_class *next; 1077 1078 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 1079 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 1080 void (*yield_task) (struct rq *rq); 1081 bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt); 1082 1083 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags); 1084 1085 struct task_struct * (*pick_next_task) (struct rq *rq); 1086 void (*put_prev_task) (struct rq *rq, struct task_struct *p); 1087 1088 #ifdef CONFIG_SMP 1089 int (*select_task_rq)(struct task_struct *p, int sd_flag, int flags); 1090 1091 void (*pre_schedule) (struct rq *this_rq, struct task_struct *task); 1092 void (*post_schedule) (struct rq *this_rq); 1093 void (*task_waking) (struct task_struct *task); 1094 void (*task_woken) (struct rq *this_rq, struct task_struct *task); 1095 1096 void (*set_cpus_allowed)(struct task_struct *p, 1097 const struct cpumask *newmask); 1098 1099 void (*rq_online)(struct rq *rq); 1100 void (*rq_offline)(struct rq *rq); 1101 #endif 1102 1103 void (*set_curr_task) (struct rq *rq); 1104 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued); 1105 void (*task_fork) (struct task_struct *p); 1106 1107 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 1108 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 1109 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 1110 int oldprio); 1111 1112 unsigned int (*get_rr_interval) (struct rq *rq, 1113 struct task_struct *task); 1114 1115 #ifdef CONFIG_FAIR_GROUP_SCHED 1116 void (*task_move_group) (struct task_struct *p, int on_rq); 1117 #endif 1118 }; 1119 1120 struct load_weight { 1121 unsigned long weight, inv_weight; 1122 }; 1123 1124 #ifdef CONFIG_SCHEDSTATS 1125 struct sched_statistics { 1126 u64 wait_start; 1127 u64 wait_max; 1128 u64 wait_count; 1129 u64 wait_sum; 1130 u64 iowait_count; 1131 u64 iowait_sum; 1132 1133 u64 sleep_start; 1134 u64 sleep_max; 1135 s64 sum_sleep_runtime; 1136 1137 u64 block_start; 1138 u64 block_max; 1139 u64 exec_max; 1140 u64 slice_max; 1141 1142 u64 nr_migrations_cold; 1143 u64 nr_failed_migrations_affine; 1144 u64 nr_failed_migrations_running; 1145 u64 nr_failed_migrations_hot; 1146 u64 nr_forced_migrations; 1147 1148 u64 nr_wakeups; 1149 u64 nr_wakeups_sync; 1150 u64 nr_wakeups_migrate; 1151 u64 nr_wakeups_local; 1152 u64 nr_wakeups_remote; 1153 u64 nr_wakeups_affine; 1154 u64 nr_wakeups_affine_attempts; 1155 u64 nr_wakeups_passive; 1156 u64 nr_wakeups_idle; 1157 }; 1158 #endif 1159 1160 struct sched_entity { 1161 struct load_weight load; /* for load-balancing */ 1162 struct rb_node run_node; 1163 struct list_head group_node; 1164 unsigned int on_rq; 1165 1166 u64 exec_start; 1167 u64 sum_exec_runtime; 1168 u64 vruntime; 1169 u64 prev_sum_exec_runtime; 1170 1171 u64 nr_migrations; 1172 1173 #ifdef CONFIG_SCHEDSTATS 1174 struct sched_statistics statistics; 1175 #endif 1176 1177 #ifdef CONFIG_FAIR_GROUP_SCHED 1178 struct sched_entity *parent; 1179 /* rq on which this entity is (to be) queued: */ 1180 struct cfs_rq *cfs_rq; 1181 /* rq "owned" by this entity/group: */ 1182 struct cfs_rq *my_q; 1183 #endif 1184 }; 1185 1186 struct sched_rt_entity { 1187 struct list_head run_list; 1188 unsigned long timeout; 1189 unsigned int time_slice; 1190 int nr_cpus_allowed; 1191 1192 struct sched_rt_entity *back; 1193 #ifdef CONFIG_RT_GROUP_SCHED 1194 struct sched_rt_entity *parent; 1195 /* rq on which this entity is (to be) queued: */ 1196 struct rt_rq *rt_rq; 1197 /* rq "owned" by this entity/group: */ 1198 struct rt_rq *my_q; 1199 #endif 1200 }; 1201 1202 /* 1203 * default timeslice is 100 msecs (used only for SCHED_RR tasks). 1204 * Timeslices get refilled after they expire. 1205 */ 1206 #define RR_TIMESLICE (100 * HZ / 1000) 1207 1208 struct rcu_node; 1209 1210 enum perf_event_task_context { 1211 perf_invalid_context = -1, 1212 perf_hw_context = 0, 1213 perf_sw_context, 1214 perf_nr_task_contexts, 1215 }; 1216 1217 struct task_struct { 1218 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1219 void *stack; 1220 atomic_t usage; 1221 unsigned int flags; /* per process flags, defined below */ 1222 unsigned int ptrace; 1223 1224 #ifdef CONFIG_SMP 1225 struct llist_node wake_entry; 1226 int on_cpu; 1227 #endif 1228 int on_rq; 1229 1230 int prio, static_prio, normal_prio; 1231 unsigned int rt_priority; 1232 const struct sched_class *sched_class; 1233 struct sched_entity se; 1234 struct sched_rt_entity rt; 1235 1236 #ifdef CONFIG_PREEMPT_NOTIFIERS 1237 /* list of struct preempt_notifier: */ 1238 struct hlist_head preempt_notifiers; 1239 #endif 1240 1241 /* 1242 * fpu_counter contains the number of consecutive context switches 1243 * that the FPU is used. If this is over a threshold, the lazy fpu 1244 * saving becomes unlazy to save the trap. This is an unsigned char 1245 * so that after 256 times the counter wraps and the behavior turns 1246 * lazy again; this to deal with bursty apps that only use FPU for 1247 * a short time 1248 */ 1249 unsigned char fpu_counter; 1250 #ifdef CONFIG_BLK_DEV_IO_TRACE 1251 unsigned int btrace_seq; 1252 #endif 1253 1254 unsigned int policy; 1255 cpumask_t cpus_allowed; 1256 1257 #ifdef CONFIG_PREEMPT_RCU 1258 int rcu_read_lock_nesting; 1259 char rcu_read_unlock_special; 1260 struct list_head rcu_node_entry; 1261 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1262 #ifdef CONFIG_TREE_PREEMPT_RCU 1263 struct rcu_node *rcu_blocked_node; 1264 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1265 #ifdef CONFIG_RCU_BOOST 1266 struct rt_mutex *rcu_boost_mutex; 1267 #endif /* #ifdef CONFIG_RCU_BOOST */ 1268 1269 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 1270 struct sched_info sched_info; 1271 #endif 1272 1273 struct list_head tasks; 1274 #ifdef CONFIG_SMP 1275 struct plist_node pushable_tasks; 1276 #endif 1277 1278 struct mm_struct *mm, *active_mm; 1279 #ifdef CONFIG_COMPAT_BRK 1280 unsigned brk_randomized:1; 1281 #endif 1282 #if defined(SPLIT_RSS_COUNTING) 1283 struct task_rss_stat rss_stat; 1284 #endif 1285 /* task state */ 1286 int exit_state; 1287 int exit_code, exit_signal; 1288 int pdeath_signal; /* The signal sent when the parent dies */ 1289 unsigned int jobctl; /* JOBCTL_*, siglock protected */ 1290 /* ??? */ 1291 unsigned int personality; 1292 unsigned did_exec:1; 1293 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1294 * execve */ 1295 unsigned in_iowait:1; 1296 1297 /* task may not gain privileges */ 1298 unsigned no_new_privs:1; 1299 1300 /* Revert to default priority/policy when forking */ 1301 unsigned sched_reset_on_fork:1; 1302 unsigned sched_contributes_to_load:1; 1303 1304 #ifdef CONFIG_GENERIC_HARDIRQS 1305 /* IRQ handler threads */ 1306 unsigned irq_thread:1; 1307 #endif 1308 1309 pid_t pid; 1310 pid_t tgid; 1311 1312 #ifdef CONFIG_CC_STACKPROTECTOR 1313 /* Canary value for the -fstack-protector gcc feature */ 1314 unsigned long stack_canary; 1315 #endif 1316 1317 /* 1318 * pointers to (original) parent process, youngest child, younger sibling, 1319 * older sibling, respectively. (p->father can be replaced with 1320 * p->real_parent->pid) 1321 */ 1322 struct task_struct __rcu *real_parent; /* real parent process */ 1323 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1324 /* 1325 * children/sibling forms the list of my natural children 1326 */ 1327 struct list_head children; /* list of my children */ 1328 struct list_head sibling; /* linkage in my parent's children list */ 1329 struct task_struct *group_leader; /* threadgroup leader */ 1330 1331 /* 1332 * ptraced is the list of tasks this task is using ptrace on. 1333 * This includes both natural children and PTRACE_ATTACH targets. 1334 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1335 */ 1336 struct list_head ptraced; 1337 struct list_head ptrace_entry; 1338 1339 /* PID/PID hash table linkage. */ 1340 struct pid_link pids[PIDTYPE_MAX]; 1341 struct list_head thread_group; 1342 1343 struct completion *vfork_done; /* for vfork() */ 1344 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1345 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1346 1347 cputime_t utime, stime, utimescaled, stimescaled; 1348 cputime_t gtime; 1349 #ifndef CONFIG_VIRT_CPU_ACCOUNTING 1350 cputime_t prev_utime, prev_stime; 1351 #endif 1352 unsigned long nvcsw, nivcsw; /* context switch counts */ 1353 struct timespec start_time; /* monotonic time */ 1354 struct timespec real_start_time; /* boot based time */ 1355 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1356 unsigned long min_flt, maj_flt; 1357 1358 struct task_cputime cputime_expires; 1359 struct list_head cpu_timers[3]; 1360 1361 /* process credentials */ 1362 const struct cred __rcu *real_cred; /* objective and real subjective task 1363 * credentials (COW) */ 1364 const struct cred __rcu *cred; /* effective (overridable) subjective task 1365 * credentials (COW) */ 1366 struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */ 1367 1368 char comm[TASK_COMM_LEN]; /* executable name excluding path 1369 - access with [gs]et_task_comm (which lock 1370 it with task_lock()) 1371 - initialized normally by setup_new_exec */ 1372 /* file system info */ 1373 int link_count, total_link_count; 1374 #ifdef CONFIG_SYSVIPC 1375 /* ipc stuff */ 1376 struct sysv_sem sysvsem; 1377 #endif 1378 #ifdef CONFIG_DETECT_HUNG_TASK 1379 /* hung task detection */ 1380 unsigned long last_switch_count; 1381 #endif 1382 /* CPU-specific state of this task */ 1383 struct thread_struct thread; 1384 /* filesystem information */ 1385 struct fs_struct *fs; 1386 /* open file information */ 1387 struct files_struct *files; 1388 /* namespaces */ 1389 struct nsproxy *nsproxy; 1390 /* signal handlers */ 1391 struct signal_struct *signal; 1392 struct sighand_struct *sighand; 1393 1394 sigset_t blocked, real_blocked; 1395 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1396 struct sigpending pending; 1397 1398 unsigned long sas_ss_sp; 1399 size_t sas_ss_size; 1400 int (*notifier)(void *priv); 1401 void *notifier_data; 1402 sigset_t *notifier_mask; 1403 struct audit_context *audit_context; 1404 #ifdef CONFIG_AUDITSYSCALL 1405 uid_t loginuid; 1406 unsigned int sessionid; 1407 #endif 1408 struct seccomp seccomp; 1409 1410 /* Thread group tracking */ 1411 u32 parent_exec_id; 1412 u32 self_exec_id; 1413 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1414 * mempolicy */ 1415 spinlock_t alloc_lock; 1416 1417 /* Protection of the PI data structures: */ 1418 raw_spinlock_t pi_lock; 1419 1420 #ifdef CONFIG_RT_MUTEXES 1421 /* PI waiters blocked on a rt_mutex held by this task */ 1422 struct plist_head pi_waiters; 1423 /* Deadlock detection and priority inheritance handling */ 1424 struct rt_mutex_waiter *pi_blocked_on; 1425 #endif 1426 1427 #ifdef CONFIG_DEBUG_MUTEXES 1428 /* mutex deadlock detection */ 1429 struct mutex_waiter *blocked_on; 1430 #endif 1431 #ifdef CONFIG_TRACE_IRQFLAGS 1432 unsigned int irq_events; 1433 unsigned long hardirq_enable_ip; 1434 unsigned long hardirq_disable_ip; 1435 unsigned int hardirq_enable_event; 1436 unsigned int hardirq_disable_event; 1437 int hardirqs_enabled; 1438 int hardirq_context; 1439 unsigned long softirq_disable_ip; 1440 unsigned long softirq_enable_ip; 1441 unsigned int softirq_disable_event; 1442 unsigned int softirq_enable_event; 1443 int softirqs_enabled; 1444 int softirq_context; 1445 #endif 1446 #ifdef CONFIG_LOCKDEP 1447 # define MAX_LOCK_DEPTH 48UL 1448 u64 curr_chain_key; 1449 int lockdep_depth; 1450 unsigned int lockdep_recursion; 1451 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1452 gfp_t lockdep_reclaim_gfp; 1453 #endif 1454 1455 /* journalling filesystem info */ 1456 void *journal_info; 1457 1458 /* stacked block device info */ 1459 struct bio_list *bio_list; 1460 1461 #ifdef CONFIG_BLOCK 1462 /* stack plugging */ 1463 struct blk_plug *plug; 1464 #endif 1465 1466 /* VM state */ 1467 struct reclaim_state *reclaim_state; 1468 1469 struct backing_dev_info *backing_dev_info; 1470 1471 struct io_context *io_context; 1472 1473 unsigned long ptrace_message; 1474 siginfo_t *last_siginfo; /* For ptrace use. */ 1475 struct task_io_accounting ioac; 1476 #if defined(CONFIG_TASK_XACCT) 1477 u64 acct_rss_mem1; /* accumulated rss usage */ 1478 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1479 cputime_t acct_timexpd; /* stime + utime since last update */ 1480 #endif 1481 #ifdef CONFIG_CPUSETS 1482 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1483 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1484 int cpuset_mem_spread_rotor; 1485 int cpuset_slab_spread_rotor; 1486 #endif 1487 #ifdef CONFIG_CGROUPS 1488 /* Control Group info protected by css_set_lock */ 1489 struct css_set __rcu *cgroups; 1490 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1491 struct list_head cg_list; 1492 #endif 1493 #ifdef CONFIG_FUTEX 1494 struct robust_list_head __user *robust_list; 1495 #ifdef CONFIG_COMPAT 1496 struct compat_robust_list_head __user *compat_robust_list; 1497 #endif 1498 struct list_head pi_state_list; 1499 struct futex_pi_state *pi_state_cache; 1500 #endif 1501 #ifdef CONFIG_PERF_EVENTS 1502 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1503 struct mutex perf_event_mutex; 1504 struct list_head perf_event_list; 1505 #endif 1506 #ifdef CONFIG_NUMA 1507 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1508 short il_next; 1509 short pref_node_fork; 1510 #endif 1511 struct rcu_head rcu; 1512 1513 /* 1514 * cache last used pipe for splice 1515 */ 1516 struct pipe_inode_info *splice_pipe; 1517 #ifdef CONFIG_TASK_DELAY_ACCT 1518 struct task_delay_info *delays; 1519 #endif 1520 #ifdef CONFIG_FAULT_INJECTION 1521 int make_it_fail; 1522 #endif 1523 /* 1524 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1525 * balance_dirty_pages() for some dirty throttling pause 1526 */ 1527 int nr_dirtied; 1528 int nr_dirtied_pause; 1529 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1530 1531 #ifdef CONFIG_LATENCYTOP 1532 int latency_record_count; 1533 struct latency_record latency_record[LT_SAVECOUNT]; 1534 #endif 1535 /* 1536 * time slack values; these are used to round up poll() and 1537 * select() etc timeout values. These are in nanoseconds. 1538 */ 1539 unsigned long timer_slack_ns; 1540 unsigned long default_timer_slack_ns; 1541 1542 struct list_head *scm_work_list; 1543 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1544 /* Index of current stored address in ret_stack */ 1545 int curr_ret_stack; 1546 /* Stack of return addresses for return function tracing */ 1547 struct ftrace_ret_stack *ret_stack; 1548 /* time stamp for last schedule */ 1549 unsigned long long ftrace_timestamp; 1550 /* 1551 * Number of functions that haven't been traced 1552 * because of depth overrun. 1553 */ 1554 atomic_t trace_overrun; 1555 /* Pause for the tracing */ 1556 atomic_t tracing_graph_pause; 1557 #endif 1558 #ifdef CONFIG_TRACING 1559 /* state flags for use by tracers */ 1560 unsigned long trace; 1561 /* bitmask and counter of trace recursion */ 1562 unsigned long trace_recursion; 1563 #endif /* CONFIG_TRACING */ 1564 #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */ 1565 struct memcg_batch_info { 1566 int do_batch; /* incremented when batch uncharge started */ 1567 struct mem_cgroup *memcg; /* target memcg of uncharge */ 1568 unsigned long nr_pages; /* uncharged usage */ 1569 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ 1570 } memcg_batch; 1571 #endif 1572 #ifdef CONFIG_HAVE_HW_BREAKPOINT 1573 atomic_t ptrace_bp_refcnt; 1574 #endif 1575 }; 1576 1577 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1578 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1579 1580 /* 1581 * Priority of a process goes from 0..MAX_PRIO-1, valid RT 1582 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH 1583 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority 1584 * values are inverted: lower p->prio value means higher priority. 1585 * 1586 * The MAX_USER_RT_PRIO value allows the actual maximum 1587 * RT priority to be separate from the value exported to 1588 * user-space. This allows kernel threads to set their 1589 * priority to a value higher than any user task. Note: 1590 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO. 1591 */ 1592 1593 #define MAX_USER_RT_PRIO 100 1594 #define MAX_RT_PRIO MAX_USER_RT_PRIO 1595 1596 #define MAX_PRIO (MAX_RT_PRIO + 40) 1597 #define DEFAULT_PRIO (MAX_RT_PRIO + 20) 1598 1599 static inline int rt_prio(int prio) 1600 { 1601 if (unlikely(prio < MAX_RT_PRIO)) 1602 return 1; 1603 return 0; 1604 } 1605 1606 static inline int rt_task(struct task_struct *p) 1607 { 1608 return rt_prio(p->prio); 1609 } 1610 1611 static inline struct pid *task_pid(struct task_struct *task) 1612 { 1613 return task->pids[PIDTYPE_PID].pid; 1614 } 1615 1616 static inline struct pid *task_tgid(struct task_struct *task) 1617 { 1618 return task->group_leader->pids[PIDTYPE_PID].pid; 1619 } 1620 1621 /* 1622 * Without tasklist or rcu lock it is not safe to dereference 1623 * the result of task_pgrp/task_session even if task == current, 1624 * we can race with another thread doing sys_setsid/sys_setpgid. 1625 */ 1626 static inline struct pid *task_pgrp(struct task_struct *task) 1627 { 1628 return task->group_leader->pids[PIDTYPE_PGID].pid; 1629 } 1630 1631 static inline struct pid *task_session(struct task_struct *task) 1632 { 1633 return task->group_leader->pids[PIDTYPE_SID].pid; 1634 } 1635 1636 struct pid_namespace; 1637 1638 /* 1639 * the helpers to get the task's different pids as they are seen 1640 * from various namespaces 1641 * 1642 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1643 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1644 * current. 1645 * task_xid_nr_ns() : id seen from the ns specified; 1646 * 1647 * set_task_vxid() : assigns a virtual id to a task; 1648 * 1649 * see also pid_nr() etc in include/linux/pid.h 1650 */ 1651 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1652 struct pid_namespace *ns); 1653 1654 static inline pid_t task_pid_nr(struct task_struct *tsk) 1655 { 1656 return tsk->pid; 1657 } 1658 1659 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1660 struct pid_namespace *ns) 1661 { 1662 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1663 } 1664 1665 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1666 { 1667 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1668 } 1669 1670 1671 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1672 { 1673 return tsk->tgid; 1674 } 1675 1676 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1677 1678 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1679 { 1680 return pid_vnr(task_tgid(tsk)); 1681 } 1682 1683 1684 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1685 struct pid_namespace *ns) 1686 { 1687 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1688 } 1689 1690 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1691 { 1692 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1693 } 1694 1695 1696 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1697 struct pid_namespace *ns) 1698 { 1699 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1700 } 1701 1702 static inline pid_t task_session_vnr(struct task_struct *tsk) 1703 { 1704 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1705 } 1706 1707 /* obsolete, do not use */ 1708 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1709 { 1710 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1711 } 1712 1713 /** 1714 * pid_alive - check that a task structure is not stale 1715 * @p: Task structure to be checked. 1716 * 1717 * Test if a process is not yet dead (at most zombie state) 1718 * If pid_alive fails, then pointers within the task structure 1719 * can be stale and must not be dereferenced. 1720 */ 1721 static inline int pid_alive(struct task_struct *p) 1722 { 1723 return p->pids[PIDTYPE_PID].pid != NULL; 1724 } 1725 1726 /** 1727 * is_global_init - check if a task structure is init 1728 * @tsk: Task structure to be checked. 1729 * 1730 * Check if a task structure is the first user space task the kernel created. 1731 */ 1732 static inline int is_global_init(struct task_struct *tsk) 1733 { 1734 return tsk->pid == 1; 1735 } 1736 1737 /* 1738 * is_container_init: 1739 * check whether in the task is init in its own pid namespace. 1740 */ 1741 extern int is_container_init(struct task_struct *tsk); 1742 1743 extern struct pid *cad_pid; 1744 1745 extern void free_task(struct task_struct *tsk); 1746 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1747 1748 extern void __put_task_struct(struct task_struct *t); 1749 1750 static inline void put_task_struct(struct task_struct *t) 1751 { 1752 if (atomic_dec_and_test(&t->usage)) 1753 __put_task_struct(t); 1754 } 1755 1756 extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st); 1757 extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st); 1758 1759 /* 1760 * Per process flags 1761 */ 1762 #define PF_EXITING 0x00000004 /* getting shut down */ 1763 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1764 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 1765 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1766 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1767 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 1768 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1769 #define PF_DUMPCORE 0x00000200 /* dumped core */ 1770 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 1771 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1772 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 1773 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1774 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1775 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1776 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1777 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 1778 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1779 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1780 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1781 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1782 #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ 1783 #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ 1784 #define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */ 1785 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1786 #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ 1787 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1788 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1789 1790 /* 1791 * Only the _current_ task can read/write to tsk->flags, but other 1792 * tasks can access tsk->flags in readonly mode for example 1793 * with tsk_used_math (like during threaded core dumping). 1794 * There is however an exception to this rule during ptrace 1795 * or during fork: the ptracer task is allowed to write to the 1796 * child->flags of its traced child (same goes for fork, the parent 1797 * can write to the child->flags), because we're guaranteed the 1798 * child is not running and in turn not changing child->flags 1799 * at the same time the parent does it. 1800 */ 1801 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1802 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1803 #define clear_used_math() clear_stopped_child_used_math(current) 1804 #define set_used_math() set_stopped_child_used_math(current) 1805 #define conditional_stopped_child_used_math(condition, child) \ 1806 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1807 #define conditional_used_math(condition) \ 1808 conditional_stopped_child_used_math(condition, current) 1809 #define copy_to_stopped_child_used_math(child) \ 1810 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1811 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1812 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1813 #define used_math() tsk_used_math(current) 1814 1815 /* 1816 * task->jobctl flags 1817 */ 1818 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 1819 1820 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 1821 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 1822 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 1823 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 1824 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 1825 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 1826 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 1827 1828 #define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) 1829 #define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) 1830 #define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) 1831 #define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) 1832 #define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) 1833 #define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) 1834 #define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) 1835 1836 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 1837 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 1838 1839 extern bool task_set_jobctl_pending(struct task_struct *task, 1840 unsigned int mask); 1841 extern void task_clear_jobctl_trapping(struct task_struct *task); 1842 extern void task_clear_jobctl_pending(struct task_struct *task, 1843 unsigned int mask); 1844 1845 #ifdef CONFIG_PREEMPT_RCU 1846 1847 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */ 1848 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */ 1849 1850 static inline void rcu_copy_process(struct task_struct *p) 1851 { 1852 p->rcu_read_lock_nesting = 0; 1853 p->rcu_read_unlock_special = 0; 1854 #ifdef CONFIG_TREE_PREEMPT_RCU 1855 p->rcu_blocked_node = NULL; 1856 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1857 #ifdef CONFIG_RCU_BOOST 1858 p->rcu_boost_mutex = NULL; 1859 #endif /* #ifdef CONFIG_RCU_BOOST */ 1860 INIT_LIST_HEAD(&p->rcu_node_entry); 1861 } 1862 1863 static inline void rcu_switch_from(struct task_struct *prev) 1864 { 1865 if (prev->rcu_read_lock_nesting != 0) 1866 rcu_preempt_note_context_switch(); 1867 } 1868 1869 #else 1870 1871 static inline void rcu_copy_process(struct task_struct *p) 1872 { 1873 } 1874 1875 static inline void rcu_switch_from(struct task_struct *prev) 1876 { 1877 } 1878 1879 #endif 1880 1881 #ifdef CONFIG_SMP 1882 extern void do_set_cpus_allowed(struct task_struct *p, 1883 const struct cpumask *new_mask); 1884 1885 extern int set_cpus_allowed_ptr(struct task_struct *p, 1886 const struct cpumask *new_mask); 1887 #else 1888 static inline void do_set_cpus_allowed(struct task_struct *p, 1889 const struct cpumask *new_mask) 1890 { 1891 } 1892 static inline int set_cpus_allowed_ptr(struct task_struct *p, 1893 const struct cpumask *new_mask) 1894 { 1895 if (!cpumask_test_cpu(0, new_mask)) 1896 return -EINVAL; 1897 return 0; 1898 } 1899 #endif 1900 1901 #ifndef CONFIG_CPUMASK_OFFSTACK 1902 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 1903 { 1904 return set_cpus_allowed_ptr(p, &new_mask); 1905 } 1906 #endif 1907 1908 /* 1909 * Do not use outside of architecture code which knows its limitations. 1910 * 1911 * sched_clock() has no promise of monotonicity or bounded drift between 1912 * CPUs, use (which you should not) requires disabling IRQs. 1913 * 1914 * Please use one of the three interfaces below. 1915 */ 1916 extern unsigned long long notrace sched_clock(void); 1917 /* 1918 * See the comment in kernel/sched/clock.c 1919 */ 1920 extern u64 cpu_clock(int cpu); 1921 extern u64 local_clock(void); 1922 extern u64 sched_clock_cpu(int cpu); 1923 1924 1925 extern void sched_clock_init(void); 1926 1927 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 1928 static inline void sched_clock_tick(void) 1929 { 1930 } 1931 1932 static inline void sched_clock_idle_sleep_event(void) 1933 { 1934 } 1935 1936 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 1937 { 1938 } 1939 #else 1940 /* 1941 * Architectures can set this to 1 if they have specified 1942 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 1943 * but then during bootup it turns out that sched_clock() 1944 * is reliable after all: 1945 */ 1946 extern int sched_clock_stable; 1947 1948 extern void sched_clock_tick(void); 1949 extern void sched_clock_idle_sleep_event(void); 1950 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1951 #endif 1952 1953 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1954 /* 1955 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 1956 * The reason for this explicit opt-in is not to have perf penalty with 1957 * slow sched_clocks. 1958 */ 1959 extern void enable_sched_clock_irqtime(void); 1960 extern void disable_sched_clock_irqtime(void); 1961 #else 1962 static inline void enable_sched_clock_irqtime(void) {} 1963 static inline void disable_sched_clock_irqtime(void) {} 1964 #endif 1965 1966 extern unsigned long long 1967 task_sched_runtime(struct task_struct *task); 1968 1969 /* sched_exec is called by processes performing an exec */ 1970 #ifdef CONFIG_SMP 1971 extern void sched_exec(void); 1972 #else 1973 #define sched_exec() {} 1974 #endif 1975 1976 extern void sched_clock_idle_sleep_event(void); 1977 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1978 1979 #ifdef CONFIG_HOTPLUG_CPU 1980 extern void idle_task_exit(void); 1981 #else 1982 static inline void idle_task_exit(void) {} 1983 #endif 1984 1985 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP) 1986 extern void wake_up_idle_cpu(int cpu); 1987 #else 1988 static inline void wake_up_idle_cpu(int cpu) { } 1989 #endif 1990 1991 extern unsigned int sysctl_sched_latency; 1992 extern unsigned int sysctl_sched_min_granularity; 1993 extern unsigned int sysctl_sched_wakeup_granularity; 1994 extern unsigned int sysctl_sched_child_runs_first; 1995 1996 enum sched_tunable_scaling { 1997 SCHED_TUNABLESCALING_NONE, 1998 SCHED_TUNABLESCALING_LOG, 1999 SCHED_TUNABLESCALING_LINEAR, 2000 SCHED_TUNABLESCALING_END, 2001 }; 2002 extern enum sched_tunable_scaling sysctl_sched_tunable_scaling; 2003 2004 #ifdef CONFIG_SCHED_DEBUG 2005 extern unsigned int sysctl_sched_migration_cost; 2006 extern unsigned int sysctl_sched_nr_migrate; 2007 extern unsigned int sysctl_sched_time_avg; 2008 extern unsigned int sysctl_timer_migration; 2009 extern unsigned int sysctl_sched_shares_window; 2010 2011 int sched_proc_update_handler(struct ctl_table *table, int write, 2012 void __user *buffer, size_t *length, 2013 loff_t *ppos); 2014 #endif 2015 #ifdef CONFIG_SCHED_DEBUG 2016 static inline unsigned int get_sysctl_timer_migration(void) 2017 { 2018 return sysctl_timer_migration; 2019 } 2020 #else 2021 static inline unsigned int get_sysctl_timer_migration(void) 2022 { 2023 return 1; 2024 } 2025 #endif 2026 extern unsigned int sysctl_sched_rt_period; 2027 extern int sysctl_sched_rt_runtime; 2028 2029 int sched_rt_handler(struct ctl_table *table, int write, 2030 void __user *buffer, size_t *lenp, 2031 loff_t *ppos); 2032 2033 #ifdef CONFIG_SCHED_AUTOGROUP 2034 extern unsigned int sysctl_sched_autogroup_enabled; 2035 2036 extern void sched_autogroup_create_attach(struct task_struct *p); 2037 extern void sched_autogroup_detach(struct task_struct *p); 2038 extern void sched_autogroup_fork(struct signal_struct *sig); 2039 extern void sched_autogroup_exit(struct signal_struct *sig); 2040 #ifdef CONFIG_PROC_FS 2041 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2042 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2043 #endif 2044 #else 2045 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2046 static inline void sched_autogroup_detach(struct task_struct *p) { } 2047 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2048 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2049 #endif 2050 2051 #ifdef CONFIG_CFS_BANDWIDTH 2052 extern unsigned int sysctl_sched_cfs_bandwidth_slice; 2053 #endif 2054 2055 #ifdef CONFIG_RT_MUTEXES 2056 extern int rt_mutex_getprio(struct task_struct *p); 2057 extern void rt_mutex_setprio(struct task_struct *p, int prio); 2058 extern void rt_mutex_adjust_pi(struct task_struct *p); 2059 static inline bool tsk_is_pi_blocked(struct task_struct *tsk) 2060 { 2061 return tsk->pi_blocked_on != NULL; 2062 } 2063 #else 2064 static inline int rt_mutex_getprio(struct task_struct *p) 2065 { 2066 return p->normal_prio; 2067 } 2068 # define rt_mutex_adjust_pi(p) do { } while (0) 2069 static inline bool tsk_is_pi_blocked(struct task_struct *tsk) 2070 { 2071 return false; 2072 } 2073 #endif 2074 2075 extern bool yield_to(struct task_struct *p, bool preempt); 2076 extern void set_user_nice(struct task_struct *p, long nice); 2077 extern int task_prio(const struct task_struct *p); 2078 extern int task_nice(const struct task_struct *p); 2079 extern int can_nice(const struct task_struct *p, const int nice); 2080 extern int task_curr(const struct task_struct *p); 2081 extern int idle_cpu(int cpu); 2082 extern int sched_setscheduler(struct task_struct *, int, 2083 const struct sched_param *); 2084 extern int sched_setscheduler_nocheck(struct task_struct *, int, 2085 const struct sched_param *); 2086 extern struct task_struct *idle_task(int cpu); 2087 /** 2088 * is_idle_task - is the specified task an idle task? 2089 * @p: the task in question. 2090 */ 2091 static inline bool is_idle_task(const struct task_struct *p) 2092 { 2093 return p->pid == 0; 2094 } 2095 extern struct task_struct *curr_task(int cpu); 2096 extern void set_curr_task(int cpu, struct task_struct *p); 2097 2098 void yield(void); 2099 2100 /* 2101 * The default (Linux) execution domain. 2102 */ 2103 extern struct exec_domain default_exec_domain; 2104 2105 union thread_union { 2106 struct thread_info thread_info; 2107 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2108 }; 2109 2110 #ifndef __HAVE_ARCH_KSTACK_END 2111 static inline int kstack_end(void *addr) 2112 { 2113 /* Reliable end of stack detection: 2114 * Some APM bios versions misalign the stack 2115 */ 2116 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2117 } 2118 #endif 2119 2120 extern union thread_union init_thread_union; 2121 extern struct task_struct init_task; 2122 2123 extern struct mm_struct init_mm; 2124 2125 extern struct pid_namespace init_pid_ns; 2126 2127 /* 2128 * find a task by one of its numerical ids 2129 * 2130 * find_task_by_pid_ns(): 2131 * finds a task by its pid in the specified namespace 2132 * find_task_by_vpid(): 2133 * finds a task by its virtual pid 2134 * 2135 * see also find_vpid() etc in include/linux/pid.h 2136 */ 2137 2138 extern struct task_struct *find_task_by_vpid(pid_t nr); 2139 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2140 struct pid_namespace *ns); 2141 2142 extern void __set_special_pids(struct pid *pid); 2143 2144 /* per-UID process charging. */ 2145 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t); 2146 static inline struct user_struct *get_uid(struct user_struct *u) 2147 { 2148 atomic_inc(&u->__count); 2149 return u; 2150 } 2151 extern void free_uid(struct user_struct *); 2152 extern void release_uids(struct user_namespace *ns); 2153 2154 #include <asm/current.h> 2155 2156 extern void xtime_update(unsigned long ticks); 2157 2158 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2159 extern int wake_up_process(struct task_struct *tsk); 2160 extern void wake_up_new_task(struct task_struct *tsk); 2161 #ifdef CONFIG_SMP 2162 extern void kick_process(struct task_struct *tsk); 2163 #else 2164 static inline void kick_process(struct task_struct *tsk) { } 2165 #endif 2166 extern void sched_fork(struct task_struct *p); 2167 extern void sched_dead(struct task_struct *p); 2168 2169 extern void proc_caches_init(void); 2170 extern void flush_signals(struct task_struct *); 2171 extern void __flush_signals(struct task_struct *); 2172 extern void ignore_signals(struct task_struct *); 2173 extern void flush_signal_handlers(struct task_struct *, int force_default); 2174 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2175 2176 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2177 { 2178 unsigned long flags; 2179 int ret; 2180 2181 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2182 ret = dequeue_signal(tsk, mask, info); 2183 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2184 2185 return ret; 2186 } 2187 2188 extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2189 sigset_t *mask); 2190 extern void unblock_all_signals(void); 2191 extern void release_task(struct task_struct * p); 2192 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2193 extern int force_sigsegv(int, struct task_struct *); 2194 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2195 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2196 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2197 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2198 const struct cred *, u32); 2199 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2200 extern int kill_pid(struct pid *pid, int sig, int priv); 2201 extern int kill_proc_info(int, struct siginfo *, pid_t); 2202 extern __must_check bool do_notify_parent(struct task_struct *, int); 2203 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2204 extern void force_sig(int, struct task_struct *); 2205 extern int send_sig(int, struct task_struct *, int); 2206 extern int zap_other_threads(struct task_struct *p); 2207 extern struct sigqueue *sigqueue_alloc(void); 2208 extern void sigqueue_free(struct sigqueue *); 2209 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2210 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2211 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long); 2212 2213 static inline int kill_cad_pid(int sig, int priv) 2214 { 2215 return kill_pid(cad_pid, sig, priv); 2216 } 2217 2218 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2219 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2220 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2221 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2222 2223 /* 2224 * True if we are on the alternate signal stack. 2225 */ 2226 static inline int on_sig_stack(unsigned long sp) 2227 { 2228 #ifdef CONFIG_STACK_GROWSUP 2229 return sp >= current->sas_ss_sp && 2230 sp - current->sas_ss_sp < current->sas_ss_size; 2231 #else 2232 return sp > current->sas_ss_sp && 2233 sp - current->sas_ss_sp <= current->sas_ss_size; 2234 #endif 2235 } 2236 2237 static inline int sas_ss_flags(unsigned long sp) 2238 { 2239 return (current->sas_ss_size == 0 ? SS_DISABLE 2240 : on_sig_stack(sp) ? SS_ONSTACK : 0); 2241 } 2242 2243 /* 2244 * Routines for handling mm_structs 2245 */ 2246 extern struct mm_struct * mm_alloc(void); 2247 2248 /* mmdrop drops the mm and the page tables */ 2249 extern void __mmdrop(struct mm_struct *); 2250 static inline void mmdrop(struct mm_struct * mm) 2251 { 2252 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2253 __mmdrop(mm); 2254 } 2255 2256 /* mmput gets rid of the mappings and all user-space */ 2257 extern void mmput(struct mm_struct *); 2258 /* Grab a reference to a task's mm, if it is not already going away */ 2259 extern struct mm_struct *get_task_mm(struct task_struct *task); 2260 /* 2261 * Grab a reference to a task's mm, if it is not already going away 2262 * and ptrace_may_access with the mode parameter passed to it 2263 * succeeds. 2264 */ 2265 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2266 /* Remove the current tasks stale references to the old mm_struct */ 2267 extern void mm_release(struct task_struct *, struct mm_struct *); 2268 /* Allocate a new mm structure and copy contents from tsk->mm */ 2269 extern struct mm_struct *dup_mm(struct task_struct *tsk); 2270 2271 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2272 struct task_struct *, struct pt_regs *); 2273 extern void flush_thread(void); 2274 extern void exit_thread(void); 2275 2276 extern void exit_files(struct task_struct *); 2277 extern void __cleanup_sighand(struct sighand_struct *); 2278 2279 extern void exit_itimers(struct signal_struct *); 2280 extern void flush_itimer_signals(void); 2281 2282 extern void do_group_exit(int); 2283 2284 extern void daemonize(const char *, ...); 2285 extern int allow_signal(int); 2286 extern int disallow_signal(int); 2287 2288 extern int do_execve(const char *, 2289 const char __user * const __user *, 2290 const char __user * const __user *, struct pt_regs *); 2291 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *); 2292 struct task_struct *fork_idle(int); 2293 2294 extern void set_task_comm(struct task_struct *tsk, char *from); 2295 extern char *get_task_comm(char *to, struct task_struct *tsk); 2296 2297 #ifdef CONFIG_SMP 2298 void scheduler_ipi(void); 2299 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2300 #else 2301 static inline void scheduler_ipi(void) { } 2302 static inline unsigned long wait_task_inactive(struct task_struct *p, 2303 long match_state) 2304 { 2305 return 1; 2306 } 2307 #endif 2308 2309 #define next_task(p) \ 2310 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2311 2312 #define for_each_process(p) \ 2313 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2314 2315 extern bool current_is_single_threaded(void); 2316 2317 /* 2318 * Careful: do_each_thread/while_each_thread is a double loop so 2319 * 'break' will not work as expected - use goto instead. 2320 */ 2321 #define do_each_thread(g, t) \ 2322 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2323 2324 #define while_each_thread(g, t) \ 2325 while ((t = next_thread(t)) != g) 2326 2327 static inline int get_nr_threads(struct task_struct *tsk) 2328 { 2329 return tsk->signal->nr_threads; 2330 } 2331 2332 static inline bool thread_group_leader(struct task_struct *p) 2333 { 2334 return p->exit_signal >= 0; 2335 } 2336 2337 /* Do to the insanities of de_thread it is possible for a process 2338 * to have the pid of the thread group leader without actually being 2339 * the thread group leader. For iteration through the pids in proc 2340 * all we care about is that we have a task with the appropriate 2341 * pid, we don't actually care if we have the right task. 2342 */ 2343 static inline int has_group_leader_pid(struct task_struct *p) 2344 { 2345 return p->pid == p->tgid; 2346 } 2347 2348 static inline 2349 int same_thread_group(struct task_struct *p1, struct task_struct *p2) 2350 { 2351 return p1->tgid == p2->tgid; 2352 } 2353 2354 static inline struct task_struct *next_thread(const struct task_struct *p) 2355 { 2356 return list_entry_rcu(p->thread_group.next, 2357 struct task_struct, thread_group); 2358 } 2359 2360 static inline int thread_group_empty(struct task_struct *p) 2361 { 2362 return list_empty(&p->thread_group); 2363 } 2364 2365 #define delay_group_leader(p) \ 2366 (thread_group_leader(p) && !thread_group_empty(p)) 2367 2368 /* 2369 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2370 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2371 * pins the final release of task.io_context. Also protects ->cpuset and 2372 * ->cgroup.subsys[]. And ->vfork_done. 2373 * 2374 * Nests both inside and outside of read_lock(&tasklist_lock). 2375 * It must not be nested with write_lock_irq(&tasklist_lock), 2376 * neither inside nor outside. 2377 */ 2378 static inline void task_lock(struct task_struct *p) 2379 { 2380 spin_lock(&p->alloc_lock); 2381 } 2382 2383 static inline void task_unlock(struct task_struct *p) 2384 { 2385 spin_unlock(&p->alloc_lock); 2386 } 2387 2388 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2389 unsigned long *flags); 2390 2391 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2392 unsigned long *flags) 2393 { 2394 struct sighand_struct *ret; 2395 2396 ret = __lock_task_sighand(tsk, flags); 2397 (void)__cond_lock(&tsk->sighand->siglock, ret); 2398 return ret; 2399 } 2400 2401 static inline void unlock_task_sighand(struct task_struct *tsk, 2402 unsigned long *flags) 2403 { 2404 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2405 } 2406 2407 #ifdef CONFIG_CGROUPS 2408 static inline void threadgroup_change_begin(struct task_struct *tsk) 2409 { 2410 down_read(&tsk->signal->group_rwsem); 2411 } 2412 static inline void threadgroup_change_end(struct task_struct *tsk) 2413 { 2414 up_read(&tsk->signal->group_rwsem); 2415 } 2416 2417 /** 2418 * threadgroup_lock - lock threadgroup 2419 * @tsk: member task of the threadgroup to lock 2420 * 2421 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter 2422 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or 2423 * perform exec. This is useful for cases where the threadgroup needs to 2424 * stay stable across blockable operations. 2425 * 2426 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for 2427 * synchronization. While held, no new task will be added to threadgroup 2428 * and no existing live task will have its PF_EXITING set. 2429 * 2430 * During exec, a task goes and puts its thread group through unusual 2431 * changes. After de-threading, exclusive access is assumed to resources 2432 * which are usually shared by tasks in the same group - e.g. sighand may 2433 * be replaced with a new one. Also, the exec'ing task takes over group 2434 * leader role including its pid. Exclude these changes while locked by 2435 * grabbing cred_guard_mutex which is used to synchronize exec path. 2436 */ 2437 static inline void threadgroup_lock(struct task_struct *tsk) 2438 { 2439 /* 2440 * exec uses exit for de-threading nesting group_rwsem inside 2441 * cred_guard_mutex. Grab cred_guard_mutex first. 2442 */ 2443 mutex_lock(&tsk->signal->cred_guard_mutex); 2444 down_write(&tsk->signal->group_rwsem); 2445 } 2446 2447 /** 2448 * threadgroup_unlock - unlock threadgroup 2449 * @tsk: member task of the threadgroup to unlock 2450 * 2451 * Reverse threadgroup_lock(). 2452 */ 2453 static inline void threadgroup_unlock(struct task_struct *tsk) 2454 { 2455 up_write(&tsk->signal->group_rwsem); 2456 mutex_unlock(&tsk->signal->cred_guard_mutex); 2457 } 2458 #else 2459 static inline void threadgroup_change_begin(struct task_struct *tsk) {} 2460 static inline void threadgroup_change_end(struct task_struct *tsk) {} 2461 static inline void threadgroup_lock(struct task_struct *tsk) {} 2462 static inline void threadgroup_unlock(struct task_struct *tsk) {} 2463 #endif 2464 2465 #ifndef __HAVE_THREAD_FUNCTIONS 2466 2467 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 2468 #define task_stack_page(task) ((task)->stack) 2469 2470 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2471 { 2472 *task_thread_info(p) = *task_thread_info(org); 2473 task_thread_info(p)->task = p; 2474 } 2475 2476 static inline unsigned long *end_of_stack(struct task_struct *p) 2477 { 2478 return (unsigned long *)(task_thread_info(p) + 1); 2479 } 2480 2481 #endif 2482 2483 static inline int object_is_on_stack(void *obj) 2484 { 2485 void *stack = task_stack_page(current); 2486 2487 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2488 } 2489 2490 extern void thread_info_cache_init(void); 2491 2492 #ifdef CONFIG_DEBUG_STACK_USAGE 2493 static inline unsigned long stack_not_used(struct task_struct *p) 2494 { 2495 unsigned long *n = end_of_stack(p); 2496 2497 do { /* Skip over canary */ 2498 n++; 2499 } while (!*n); 2500 2501 return (unsigned long)n - (unsigned long)end_of_stack(p); 2502 } 2503 #endif 2504 2505 /* set thread flags in other task's structures 2506 * - see asm/thread_info.h for TIF_xxxx flags available 2507 */ 2508 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2509 { 2510 set_ti_thread_flag(task_thread_info(tsk), flag); 2511 } 2512 2513 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2514 { 2515 clear_ti_thread_flag(task_thread_info(tsk), flag); 2516 } 2517 2518 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2519 { 2520 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2521 } 2522 2523 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2524 { 2525 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2526 } 2527 2528 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2529 { 2530 return test_ti_thread_flag(task_thread_info(tsk), flag); 2531 } 2532 2533 static inline void set_tsk_need_resched(struct task_struct *tsk) 2534 { 2535 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2536 } 2537 2538 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2539 { 2540 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2541 } 2542 2543 static inline int test_tsk_need_resched(struct task_struct *tsk) 2544 { 2545 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2546 } 2547 2548 static inline int restart_syscall(void) 2549 { 2550 set_tsk_thread_flag(current, TIF_SIGPENDING); 2551 return -ERESTARTNOINTR; 2552 } 2553 2554 static inline int signal_pending(struct task_struct *p) 2555 { 2556 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2557 } 2558 2559 static inline int __fatal_signal_pending(struct task_struct *p) 2560 { 2561 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2562 } 2563 2564 static inline int fatal_signal_pending(struct task_struct *p) 2565 { 2566 return signal_pending(p) && __fatal_signal_pending(p); 2567 } 2568 2569 static inline int signal_pending_state(long state, struct task_struct *p) 2570 { 2571 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2572 return 0; 2573 if (!signal_pending(p)) 2574 return 0; 2575 2576 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2577 } 2578 2579 static inline int need_resched(void) 2580 { 2581 return unlikely(test_thread_flag(TIF_NEED_RESCHED)); 2582 } 2583 2584 /* 2585 * cond_resched() and cond_resched_lock(): latency reduction via 2586 * explicit rescheduling in places that are safe. The return 2587 * value indicates whether a reschedule was done in fact. 2588 * cond_resched_lock() will drop the spinlock before scheduling, 2589 * cond_resched_softirq() will enable bhs before scheduling. 2590 */ 2591 extern int _cond_resched(void); 2592 2593 #define cond_resched() ({ \ 2594 __might_sleep(__FILE__, __LINE__, 0); \ 2595 _cond_resched(); \ 2596 }) 2597 2598 extern int __cond_resched_lock(spinlock_t *lock); 2599 2600 #ifdef CONFIG_PREEMPT_COUNT 2601 #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2602 #else 2603 #define PREEMPT_LOCK_OFFSET 0 2604 #endif 2605 2606 #define cond_resched_lock(lock) ({ \ 2607 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2608 __cond_resched_lock(lock); \ 2609 }) 2610 2611 extern int __cond_resched_softirq(void); 2612 2613 #define cond_resched_softirq() ({ \ 2614 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2615 __cond_resched_softirq(); \ 2616 }) 2617 2618 /* 2619 * Does a critical section need to be broken due to another 2620 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2621 * but a general need for low latency) 2622 */ 2623 static inline int spin_needbreak(spinlock_t *lock) 2624 { 2625 #ifdef CONFIG_PREEMPT 2626 return spin_is_contended(lock); 2627 #else 2628 return 0; 2629 #endif 2630 } 2631 2632 /* 2633 * Thread group CPU time accounting. 2634 */ 2635 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 2636 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 2637 2638 static inline void thread_group_cputime_init(struct signal_struct *sig) 2639 { 2640 raw_spin_lock_init(&sig->cputimer.lock); 2641 } 2642 2643 /* 2644 * Reevaluate whether the task has signals pending delivery. 2645 * Wake the task if so. 2646 * This is required every time the blocked sigset_t changes. 2647 * callers must hold sighand->siglock. 2648 */ 2649 extern void recalc_sigpending_and_wake(struct task_struct *t); 2650 extern void recalc_sigpending(void); 2651 2652 extern void signal_wake_up(struct task_struct *t, int resume_stopped); 2653 2654 /* 2655 * Wrappers for p->thread_info->cpu access. No-op on UP. 2656 */ 2657 #ifdef CONFIG_SMP 2658 2659 static inline unsigned int task_cpu(const struct task_struct *p) 2660 { 2661 return task_thread_info(p)->cpu; 2662 } 2663 2664 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2665 2666 #else 2667 2668 static inline unsigned int task_cpu(const struct task_struct *p) 2669 { 2670 return 0; 2671 } 2672 2673 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2674 { 2675 } 2676 2677 #endif /* CONFIG_SMP */ 2678 2679 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2680 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2681 2682 extern void normalize_rt_tasks(void); 2683 2684 #ifdef CONFIG_CGROUP_SCHED 2685 2686 extern struct task_group root_task_group; 2687 2688 extern struct task_group *sched_create_group(struct task_group *parent); 2689 extern void sched_destroy_group(struct task_group *tg); 2690 extern void sched_move_task(struct task_struct *tsk); 2691 #ifdef CONFIG_FAIR_GROUP_SCHED 2692 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 2693 extern unsigned long sched_group_shares(struct task_group *tg); 2694 #endif 2695 #ifdef CONFIG_RT_GROUP_SCHED 2696 extern int sched_group_set_rt_runtime(struct task_group *tg, 2697 long rt_runtime_us); 2698 extern long sched_group_rt_runtime(struct task_group *tg); 2699 extern int sched_group_set_rt_period(struct task_group *tg, 2700 long rt_period_us); 2701 extern long sched_group_rt_period(struct task_group *tg); 2702 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 2703 #endif 2704 #endif 2705 2706 extern int task_can_switch_user(struct user_struct *up, 2707 struct task_struct *tsk); 2708 2709 #ifdef CONFIG_TASK_XACCT 2710 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2711 { 2712 tsk->ioac.rchar += amt; 2713 } 2714 2715 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2716 { 2717 tsk->ioac.wchar += amt; 2718 } 2719 2720 static inline void inc_syscr(struct task_struct *tsk) 2721 { 2722 tsk->ioac.syscr++; 2723 } 2724 2725 static inline void inc_syscw(struct task_struct *tsk) 2726 { 2727 tsk->ioac.syscw++; 2728 } 2729 #else 2730 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2731 { 2732 } 2733 2734 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2735 { 2736 } 2737 2738 static inline void inc_syscr(struct task_struct *tsk) 2739 { 2740 } 2741 2742 static inline void inc_syscw(struct task_struct *tsk) 2743 { 2744 } 2745 #endif 2746 2747 #ifndef TASK_SIZE_OF 2748 #define TASK_SIZE_OF(tsk) TASK_SIZE 2749 #endif 2750 2751 #ifdef CONFIG_MM_OWNER 2752 extern void mm_update_next_owner(struct mm_struct *mm); 2753 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); 2754 #else 2755 static inline void mm_update_next_owner(struct mm_struct *mm) 2756 { 2757 } 2758 2759 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) 2760 { 2761 } 2762 #endif /* CONFIG_MM_OWNER */ 2763 2764 static inline unsigned long task_rlimit(const struct task_struct *tsk, 2765 unsigned int limit) 2766 { 2767 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); 2768 } 2769 2770 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 2771 unsigned int limit) 2772 { 2773 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); 2774 } 2775 2776 static inline unsigned long rlimit(unsigned int limit) 2777 { 2778 return task_rlimit(current, limit); 2779 } 2780 2781 static inline unsigned long rlimit_max(unsigned int limit) 2782 { 2783 return task_rlimit_max(current, limit); 2784 } 2785 2786 #endif /* __KERNEL__ */ 2787 2788 #endif 2789