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 #include <linux/uidgid.h> 94 95 #include <asm/processor.h> 96 97 struct exec_domain; 98 struct futex_pi_state; 99 struct robust_list_head; 100 struct bio_list; 101 struct fs_struct; 102 struct perf_event_context; 103 struct blk_plug; 104 105 /* 106 * List of flags we want to share for kernel threads, 107 * if only because they are not used by them anyway. 108 */ 109 #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND) 110 111 /* 112 * These are the constant used to fake the fixed-point load-average 113 * counting. Some notes: 114 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 115 * a load-average precision of 10 bits integer + 11 bits fractional 116 * - if you want to count load-averages more often, you need more 117 * precision, or rounding will get you. With 2-second counting freq, 118 * the EXP_n values would be 1981, 2034 and 2043 if still using only 119 * 11 bit fractions. 120 */ 121 extern unsigned long avenrun[]; /* Load averages */ 122 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 123 124 #define FSHIFT 11 /* nr of bits of precision */ 125 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 126 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 127 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 128 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 129 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 130 131 #define CALC_LOAD(load,exp,n) \ 132 load *= exp; \ 133 load += n*(FIXED_1-exp); \ 134 load >>= FSHIFT; 135 136 extern unsigned long total_forks; 137 extern int nr_threads; 138 DECLARE_PER_CPU(unsigned long, process_counts); 139 extern int nr_processes(void); 140 extern unsigned long nr_running(void); 141 extern unsigned long nr_uninterruptible(void); 142 extern unsigned long nr_iowait(void); 143 extern unsigned long nr_iowait_cpu(int cpu); 144 extern unsigned long this_cpu_load(void); 145 146 147 extern void calc_global_load(unsigned long ticks); 148 149 extern unsigned long get_parent_ip(unsigned long addr); 150 151 struct seq_file; 152 struct cfs_rq; 153 struct task_group; 154 #ifdef CONFIG_SCHED_DEBUG 155 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 156 extern void proc_sched_set_task(struct task_struct *p); 157 extern void 158 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 159 #else 160 static inline void 161 proc_sched_show_task(struct task_struct *p, struct seq_file *m) 162 { 163 } 164 static inline void proc_sched_set_task(struct task_struct *p) 165 { 166 } 167 static inline void 168 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) 169 { 170 } 171 #endif 172 173 /* 174 * Task state bitmask. NOTE! These bits are also 175 * encoded in fs/proc/array.c: get_task_state(). 176 * 177 * We have two separate sets of flags: task->state 178 * is about runnability, while task->exit_state are 179 * about the task exiting. Confusing, but this way 180 * modifying one set can't modify the other one by 181 * mistake. 182 */ 183 #define TASK_RUNNING 0 184 #define TASK_INTERRUPTIBLE 1 185 #define TASK_UNINTERRUPTIBLE 2 186 #define __TASK_STOPPED 4 187 #define __TASK_TRACED 8 188 /* in tsk->exit_state */ 189 #define EXIT_ZOMBIE 16 190 #define EXIT_DEAD 32 191 /* in tsk->state again */ 192 #define TASK_DEAD 64 193 #define TASK_WAKEKILL 128 194 #define TASK_WAKING 256 195 #define TASK_STATE_MAX 512 196 197 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW" 198 199 extern char ___assert_task_state[1 - 2*!!( 200 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 201 202 /* Convenience macros for the sake of set_task_state */ 203 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 204 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 205 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 206 207 /* Convenience macros for the sake of wake_up */ 208 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 209 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 210 211 /* get_task_state() */ 212 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 213 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 214 __TASK_TRACED) 215 216 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 217 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 218 #define task_is_dead(task) ((task)->exit_state != 0) 219 #define task_is_stopped_or_traced(task) \ 220 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 221 #define task_contributes_to_load(task) \ 222 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 223 (task->flags & PF_FROZEN) == 0) 224 225 #define __set_task_state(tsk, state_value) \ 226 do { (tsk)->state = (state_value); } while (0) 227 #define set_task_state(tsk, state_value) \ 228 set_mb((tsk)->state, (state_value)) 229 230 /* 231 * set_current_state() includes a barrier so that the write of current->state 232 * is correctly serialised wrt the caller's subsequent test of whether to 233 * actually sleep: 234 * 235 * set_current_state(TASK_UNINTERRUPTIBLE); 236 * if (do_i_need_to_sleep()) 237 * schedule(); 238 * 239 * If the caller does not need such serialisation then use __set_current_state() 240 */ 241 #define __set_current_state(state_value) \ 242 do { current->state = (state_value); } while (0) 243 #define set_current_state(state_value) \ 244 set_mb(current->state, (state_value)) 245 246 /* Task command name length */ 247 #define TASK_COMM_LEN 16 248 249 #include <linux/spinlock.h> 250 251 /* 252 * This serializes "schedule()" and also protects 253 * the run-queue from deletions/modifications (but 254 * _adding_ to the beginning of the run-queue has 255 * a separate lock). 256 */ 257 extern rwlock_t tasklist_lock; 258 extern spinlock_t mmlist_lock; 259 260 struct task_struct; 261 262 #ifdef CONFIG_PROVE_RCU 263 extern int lockdep_tasklist_lock_is_held(void); 264 #endif /* #ifdef CONFIG_PROVE_RCU */ 265 266 extern void sched_init(void); 267 extern void sched_init_smp(void); 268 extern asmlinkage void schedule_tail(struct task_struct *prev); 269 extern void init_idle(struct task_struct *idle, int cpu); 270 extern void init_idle_bootup_task(struct task_struct *idle); 271 272 extern int runqueue_is_locked(int cpu); 273 274 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ) 275 extern void select_nohz_load_balancer(int stop_tick); 276 extern void set_cpu_sd_state_idle(void); 277 extern int get_nohz_timer_target(void); 278 #else 279 static inline void select_nohz_load_balancer(int stop_tick) { } 280 static inline void set_cpu_sd_state_idle(void) { } 281 #endif 282 283 /* 284 * Only dump TASK_* tasks. (0 for all tasks) 285 */ 286 extern void show_state_filter(unsigned long state_filter); 287 288 static inline void show_state(void) 289 { 290 show_state_filter(0); 291 } 292 293 extern void show_regs(struct pt_regs *); 294 295 /* 296 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 297 * task), SP is the stack pointer of the first frame that should be shown in the back 298 * trace (or NULL if the entire call-chain of the task should be shown). 299 */ 300 extern void show_stack(struct task_struct *task, unsigned long *sp); 301 302 void io_schedule(void); 303 long io_schedule_timeout(long timeout); 304 305 extern void cpu_init (void); 306 extern void trap_init(void); 307 extern void update_process_times(int user); 308 extern void scheduler_tick(void); 309 310 extern void sched_show_task(struct task_struct *p); 311 312 #ifdef CONFIG_LOCKUP_DETECTOR 313 extern void touch_softlockup_watchdog(void); 314 extern void touch_softlockup_watchdog_sync(void); 315 extern void touch_all_softlockup_watchdogs(void); 316 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 317 void __user *buffer, 318 size_t *lenp, loff_t *ppos); 319 extern unsigned int softlockup_panic; 320 void lockup_detector_init(void); 321 #else 322 static inline void touch_softlockup_watchdog(void) 323 { 324 } 325 static inline void touch_softlockup_watchdog_sync(void) 326 { 327 } 328 static inline void touch_all_softlockup_watchdogs(void) 329 { 330 } 331 static inline void lockup_detector_init(void) 332 { 333 } 334 #endif 335 336 #ifdef CONFIG_DETECT_HUNG_TASK 337 extern unsigned int sysctl_hung_task_panic; 338 extern unsigned long sysctl_hung_task_check_count; 339 extern unsigned long sysctl_hung_task_timeout_secs; 340 extern unsigned long sysctl_hung_task_warnings; 341 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, 342 void __user *buffer, 343 size_t *lenp, loff_t *ppos); 344 #else 345 /* Avoid need for ifdefs elsewhere in the code */ 346 enum { sysctl_hung_task_timeout_secs = 0 }; 347 #endif 348 349 /* Attach to any functions which should be ignored in wchan output. */ 350 #define __sched __attribute__((__section__(".sched.text"))) 351 352 /* Linker adds these: start and end of __sched functions */ 353 extern char __sched_text_start[], __sched_text_end[]; 354 355 /* Is this address in the __sched functions? */ 356 extern int in_sched_functions(unsigned long addr); 357 358 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 359 extern signed long schedule_timeout(signed long timeout); 360 extern signed long schedule_timeout_interruptible(signed long timeout); 361 extern signed long schedule_timeout_killable(signed long timeout); 362 extern signed long schedule_timeout_uninterruptible(signed long timeout); 363 asmlinkage void schedule(void); 364 extern void schedule_preempt_disabled(void); 365 extern int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner); 366 367 struct nsproxy; 368 struct user_namespace; 369 370 /* 371 * Default maximum number of active map areas, this limits the number of vmas 372 * per mm struct. Users can overwrite this number by sysctl but there is a 373 * problem. 374 * 375 * When a program's coredump is generated as ELF format, a section is created 376 * per a vma. In ELF, the number of sections is represented in unsigned short. 377 * This means the number of sections should be smaller than 65535 at coredump. 378 * Because the kernel adds some informative sections to a image of program at 379 * generating coredump, we need some margin. The number of extra sections is 380 * 1-3 now and depends on arch. We use "5" as safe margin, here. 381 */ 382 #define MAPCOUNT_ELF_CORE_MARGIN (5) 383 #define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) 384 385 extern int sysctl_max_map_count; 386 387 #include <linux/aio.h> 388 389 #ifdef CONFIG_MMU 390 extern void arch_pick_mmap_layout(struct mm_struct *mm); 391 extern unsigned long 392 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 393 unsigned long, unsigned long); 394 extern unsigned long 395 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 396 unsigned long len, unsigned long pgoff, 397 unsigned long flags); 398 extern void arch_unmap_area(struct mm_struct *, unsigned long); 399 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); 400 #else 401 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 402 #endif 403 404 405 extern void set_dumpable(struct mm_struct *mm, int value); 406 extern int get_dumpable(struct mm_struct *mm); 407 408 /* mm flags */ 409 /* dumpable bits */ 410 #define MMF_DUMPABLE 0 /* core dump is permitted */ 411 #define MMF_DUMP_SECURELY 1 /* core file is readable only by root */ 412 413 #define MMF_DUMPABLE_BITS 2 414 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 415 416 /* coredump filter bits */ 417 #define MMF_DUMP_ANON_PRIVATE 2 418 #define MMF_DUMP_ANON_SHARED 3 419 #define MMF_DUMP_MAPPED_PRIVATE 4 420 #define MMF_DUMP_MAPPED_SHARED 5 421 #define MMF_DUMP_ELF_HEADERS 6 422 #define MMF_DUMP_HUGETLB_PRIVATE 7 423 #define MMF_DUMP_HUGETLB_SHARED 8 424 425 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 426 #define MMF_DUMP_FILTER_BITS 7 427 #define MMF_DUMP_FILTER_MASK \ 428 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 429 #define MMF_DUMP_FILTER_DEFAULT \ 430 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 431 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 432 433 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 434 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 435 #else 436 # define MMF_DUMP_MASK_DEFAULT_ELF 0 437 #endif 438 /* leave room for more dump flags */ 439 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 440 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 441 442 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 443 444 struct sighand_struct { 445 atomic_t count; 446 struct k_sigaction action[_NSIG]; 447 spinlock_t siglock; 448 wait_queue_head_t signalfd_wqh; 449 }; 450 451 struct pacct_struct { 452 int ac_flag; 453 long ac_exitcode; 454 unsigned long ac_mem; 455 cputime_t ac_utime, ac_stime; 456 unsigned long ac_minflt, ac_majflt; 457 }; 458 459 struct cpu_itimer { 460 cputime_t expires; 461 cputime_t incr; 462 u32 error; 463 u32 incr_error; 464 }; 465 466 /** 467 * struct task_cputime - collected CPU time counts 468 * @utime: time spent in user mode, in &cputime_t units 469 * @stime: time spent in kernel mode, in &cputime_t units 470 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 471 * 472 * This structure groups together three kinds of CPU time that are 473 * tracked for threads and thread groups. Most things considering 474 * CPU time want to group these counts together and treat all three 475 * of them in parallel. 476 */ 477 struct task_cputime { 478 cputime_t utime; 479 cputime_t stime; 480 unsigned long long sum_exec_runtime; 481 }; 482 /* Alternate field names when used to cache expirations. */ 483 #define prof_exp stime 484 #define virt_exp utime 485 #define sched_exp sum_exec_runtime 486 487 #define INIT_CPUTIME \ 488 (struct task_cputime) { \ 489 .utime = 0, \ 490 .stime = 0, \ 491 .sum_exec_runtime = 0, \ 492 } 493 494 /* 495 * Disable preemption until the scheduler is running. 496 * Reset by start_kernel()->sched_init()->init_idle(). 497 * 498 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 499 * before the scheduler is active -- see should_resched(). 500 */ 501 #define INIT_PREEMPT_COUNT (1 + PREEMPT_ACTIVE) 502 503 /** 504 * struct thread_group_cputimer - thread group interval timer counts 505 * @cputime: thread group interval timers. 506 * @running: non-zero when there are timers running and 507 * @cputime receives updates. 508 * @lock: lock for fields in this struct. 509 * 510 * This structure contains the version of task_cputime, above, that is 511 * used for thread group CPU timer calculations. 512 */ 513 struct thread_group_cputimer { 514 struct task_cputime cputime; 515 int running; 516 raw_spinlock_t lock; 517 }; 518 519 #include <linux/rwsem.h> 520 struct autogroup; 521 522 /* 523 * NOTE! "signal_struct" does not have its own 524 * locking, because a shared signal_struct always 525 * implies a shared sighand_struct, so locking 526 * sighand_struct is always a proper superset of 527 * the locking of signal_struct. 528 */ 529 struct signal_struct { 530 atomic_t sigcnt; 531 atomic_t live; 532 int nr_threads; 533 534 wait_queue_head_t wait_chldexit; /* for wait4() */ 535 536 /* current thread group signal load-balancing target: */ 537 struct task_struct *curr_target; 538 539 /* shared signal handling: */ 540 struct sigpending shared_pending; 541 542 /* thread group exit support */ 543 int group_exit_code; 544 /* overloaded: 545 * - notify group_exit_task when ->count is equal to notify_count 546 * - everyone except group_exit_task is stopped during signal delivery 547 * of fatal signals, group_exit_task processes the signal. 548 */ 549 int notify_count; 550 struct task_struct *group_exit_task; 551 552 /* thread group stop support, overloads group_exit_code too */ 553 int group_stop_count; 554 unsigned int flags; /* see SIGNAL_* flags below */ 555 556 /* 557 * PR_SET_CHILD_SUBREAPER marks a process, like a service 558 * manager, to re-parent orphan (double-forking) child processes 559 * to this process instead of 'init'. The service manager is 560 * able to receive SIGCHLD signals and is able to investigate 561 * the process until it calls wait(). All children of this 562 * process will inherit a flag if they should look for a 563 * child_subreaper process at exit. 564 */ 565 unsigned int is_child_subreaper:1; 566 unsigned int has_child_subreaper:1; 567 568 /* POSIX.1b Interval Timers */ 569 struct list_head posix_timers; 570 571 /* ITIMER_REAL timer for the process */ 572 struct hrtimer real_timer; 573 struct pid *leader_pid; 574 ktime_t it_real_incr; 575 576 /* 577 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 578 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 579 * values are defined to 0 and 1 respectively 580 */ 581 struct cpu_itimer it[2]; 582 583 /* 584 * Thread group totals for process CPU timers. 585 * See thread_group_cputimer(), et al, for details. 586 */ 587 struct thread_group_cputimer cputimer; 588 589 /* Earliest-expiration cache. */ 590 struct task_cputime cputime_expires; 591 592 struct list_head cpu_timers[3]; 593 594 struct pid *tty_old_pgrp; 595 596 /* boolean value for session group leader */ 597 int leader; 598 599 struct tty_struct *tty; /* NULL if no tty */ 600 601 #ifdef CONFIG_SCHED_AUTOGROUP 602 struct autogroup *autogroup; 603 #endif 604 /* 605 * Cumulative resource counters for dead threads in the group, 606 * and for reaped dead child processes forked by this group. 607 * Live threads maintain their own counters and add to these 608 * in __exit_signal, except for the group leader. 609 */ 610 cputime_t utime, stime, cutime, cstime; 611 cputime_t gtime; 612 cputime_t cgtime; 613 #ifndef CONFIG_VIRT_CPU_ACCOUNTING 614 cputime_t prev_utime, prev_stime; 615 #endif 616 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 617 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 618 unsigned long inblock, oublock, cinblock, coublock; 619 unsigned long maxrss, cmaxrss; 620 struct task_io_accounting ioac; 621 622 /* 623 * Cumulative ns of schedule CPU time fo dead threads in the 624 * group, not including a zombie group leader, (This only differs 625 * from jiffies_to_ns(utime + stime) if sched_clock uses something 626 * other than jiffies.) 627 */ 628 unsigned long long sum_sched_runtime; 629 630 /* 631 * We don't bother to synchronize most readers of this at all, 632 * because there is no reader checking a limit that actually needs 633 * to get both rlim_cur and rlim_max atomically, and either one 634 * alone is a single word that can safely be read normally. 635 * getrlimit/setrlimit use task_lock(current->group_leader) to 636 * protect this instead of the siglock, because they really 637 * have no need to disable irqs. 638 */ 639 struct rlimit rlim[RLIM_NLIMITS]; 640 641 #ifdef CONFIG_BSD_PROCESS_ACCT 642 struct pacct_struct pacct; /* per-process accounting information */ 643 #endif 644 #ifdef CONFIG_TASKSTATS 645 struct taskstats *stats; 646 #endif 647 #ifdef CONFIG_AUDIT 648 unsigned audit_tty; 649 struct tty_audit_buf *tty_audit_buf; 650 #endif 651 #ifdef CONFIG_CGROUPS 652 /* 653 * group_rwsem prevents new tasks from entering the threadgroup and 654 * member tasks from exiting,a more specifically, setting of 655 * PF_EXITING. fork and exit paths are protected with this rwsem 656 * using threadgroup_change_begin/end(). Users which require 657 * threadgroup to remain stable should use threadgroup_[un]lock() 658 * which also takes care of exec path. Currently, cgroup is the 659 * only user. 660 */ 661 struct rw_semaphore group_rwsem; 662 #endif 663 664 int oom_adj; /* OOM kill score adjustment (bit shift) */ 665 int oom_score_adj; /* OOM kill score adjustment */ 666 int oom_score_adj_min; /* OOM kill score adjustment minimum value. 667 * Only settable by CAP_SYS_RESOURCE. */ 668 669 struct mutex cred_guard_mutex; /* guard against foreign influences on 670 * credential calculations 671 * (notably. ptrace) */ 672 }; 673 674 /* Context switch must be unlocked if interrupts are to be enabled */ 675 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW 676 # define __ARCH_WANT_UNLOCKED_CTXSW 677 #endif 678 679 /* 680 * Bits in flags field of signal_struct. 681 */ 682 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 683 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 684 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 685 /* 686 * Pending notifications to parent. 687 */ 688 #define SIGNAL_CLD_STOPPED 0x00000010 689 #define SIGNAL_CLD_CONTINUED 0x00000020 690 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 691 692 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 693 694 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 695 static inline int signal_group_exit(const struct signal_struct *sig) 696 { 697 return (sig->flags & SIGNAL_GROUP_EXIT) || 698 (sig->group_exit_task != NULL); 699 } 700 701 /* 702 * Some day this will be a full-fledged user tracking system.. 703 */ 704 struct user_struct { 705 atomic_t __count; /* reference count */ 706 atomic_t processes; /* How many processes does this user have? */ 707 atomic_t files; /* How many open files does this user have? */ 708 atomic_t sigpending; /* How many pending signals does this user have? */ 709 #ifdef CONFIG_INOTIFY_USER 710 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 711 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 712 #endif 713 #ifdef CONFIG_FANOTIFY 714 atomic_t fanotify_listeners; 715 #endif 716 #ifdef CONFIG_EPOLL 717 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 718 #endif 719 #ifdef CONFIG_POSIX_MQUEUE 720 /* protected by mq_lock */ 721 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 722 #endif 723 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 724 725 #ifdef CONFIG_KEYS 726 struct key *uid_keyring; /* UID specific keyring */ 727 struct key *session_keyring; /* UID's default session keyring */ 728 #endif 729 730 /* Hash table maintenance information */ 731 struct hlist_node uidhash_node; 732 kuid_t uid; 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(kuid_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 pid_t pid; 1305 pid_t tgid; 1306 1307 #ifdef CONFIG_CC_STACKPROTECTOR 1308 /* Canary value for the -fstack-protector gcc feature */ 1309 unsigned long stack_canary; 1310 #endif 1311 /* 1312 * pointers to (original) parent process, youngest child, younger sibling, 1313 * older sibling, respectively. (p->father can be replaced with 1314 * p->real_parent->pid) 1315 */ 1316 struct task_struct __rcu *real_parent; /* real parent process */ 1317 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1318 /* 1319 * children/sibling forms the list of my natural children 1320 */ 1321 struct list_head children; /* list of my children */ 1322 struct list_head sibling; /* linkage in my parent's children list */ 1323 struct task_struct *group_leader; /* threadgroup leader */ 1324 1325 /* 1326 * ptraced is the list of tasks this task is using ptrace on. 1327 * This includes both natural children and PTRACE_ATTACH targets. 1328 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1329 */ 1330 struct list_head ptraced; 1331 struct list_head ptrace_entry; 1332 1333 /* PID/PID hash table linkage. */ 1334 struct pid_link pids[PIDTYPE_MAX]; 1335 struct list_head thread_group; 1336 1337 struct completion *vfork_done; /* for vfork() */ 1338 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1339 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1340 1341 cputime_t utime, stime, utimescaled, stimescaled; 1342 cputime_t gtime; 1343 #ifndef CONFIG_VIRT_CPU_ACCOUNTING 1344 cputime_t prev_utime, prev_stime; 1345 #endif 1346 unsigned long nvcsw, nivcsw; /* context switch counts */ 1347 struct timespec start_time; /* monotonic time */ 1348 struct timespec real_start_time; /* boot based time */ 1349 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1350 unsigned long min_flt, maj_flt; 1351 1352 struct task_cputime cputime_expires; 1353 struct list_head cpu_timers[3]; 1354 1355 /* process credentials */ 1356 const struct cred __rcu *real_cred; /* objective and real subjective task 1357 * credentials (COW) */ 1358 const struct cred __rcu *cred; /* effective (overridable) subjective task 1359 * credentials (COW) */ 1360 char comm[TASK_COMM_LEN]; /* executable name excluding path 1361 - access with [gs]et_task_comm (which lock 1362 it with task_lock()) 1363 - initialized normally by setup_new_exec */ 1364 /* file system info */ 1365 int link_count, total_link_count; 1366 #ifdef CONFIG_SYSVIPC 1367 /* ipc stuff */ 1368 struct sysv_sem sysvsem; 1369 #endif 1370 #ifdef CONFIG_DETECT_HUNG_TASK 1371 /* hung task detection */ 1372 unsigned long last_switch_count; 1373 #endif 1374 /* CPU-specific state of this task */ 1375 struct thread_struct thread; 1376 /* filesystem information */ 1377 struct fs_struct *fs; 1378 /* open file information */ 1379 struct files_struct *files; 1380 /* namespaces */ 1381 struct nsproxy *nsproxy; 1382 /* signal handlers */ 1383 struct signal_struct *signal; 1384 struct sighand_struct *sighand; 1385 1386 sigset_t blocked, real_blocked; 1387 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1388 struct sigpending pending; 1389 1390 unsigned long sas_ss_sp; 1391 size_t sas_ss_size; 1392 int (*notifier)(void *priv); 1393 void *notifier_data; 1394 sigset_t *notifier_mask; 1395 struct hlist_head task_works; 1396 1397 struct audit_context *audit_context; 1398 #ifdef CONFIG_AUDITSYSCALL 1399 uid_t loginuid; 1400 unsigned int sessionid; 1401 #endif 1402 struct seccomp seccomp; 1403 1404 /* Thread group tracking */ 1405 u32 parent_exec_id; 1406 u32 self_exec_id; 1407 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1408 * mempolicy */ 1409 spinlock_t alloc_lock; 1410 1411 /* Protection of the PI data structures: */ 1412 raw_spinlock_t pi_lock; 1413 1414 #ifdef CONFIG_RT_MUTEXES 1415 /* PI waiters blocked on a rt_mutex held by this task */ 1416 struct plist_head pi_waiters; 1417 /* Deadlock detection and priority inheritance handling */ 1418 struct rt_mutex_waiter *pi_blocked_on; 1419 #endif 1420 1421 #ifdef CONFIG_DEBUG_MUTEXES 1422 /* mutex deadlock detection */ 1423 struct mutex_waiter *blocked_on; 1424 #endif 1425 #ifdef CONFIG_TRACE_IRQFLAGS 1426 unsigned int irq_events; 1427 unsigned long hardirq_enable_ip; 1428 unsigned long hardirq_disable_ip; 1429 unsigned int hardirq_enable_event; 1430 unsigned int hardirq_disable_event; 1431 int hardirqs_enabled; 1432 int hardirq_context; 1433 unsigned long softirq_disable_ip; 1434 unsigned long softirq_enable_ip; 1435 unsigned int softirq_disable_event; 1436 unsigned int softirq_enable_event; 1437 int softirqs_enabled; 1438 int softirq_context; 1439 #endif 1440 #ifdef CONFIG_LOCKDEP 1441 # define MAX_LOCK_DEPTH 48UL 1442 u64 curr_chain_key; 1443 int lockdep_depth; 1444 unsigned int lockdep_recursion; 1445 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1446 gfp_t lockdep_reclaim_gfp; 1447 #endif 1448 1449 /* journalling filesystem info */ 1450 void *journal_info; 1451 1452 /* stacked block device info */ 1453 struct bio_list *bio_list; 1454 1455 #ifdef CONFIG_BLOCK 1456 /* stack plugging */ 1457 struct blk_plug *plug; 1458 #endif 1459 1460 /* VM state */ 1461 struct reclaim_state *reclaim_state; 1462 1463 struct backing_dev_info *backing_dev_info; 1464 1465 struct io_context *io_context; 1466 1467 unsigned long ptrace_message; 1468 siginfo_t *last_siginfo; /* For ptrace use. */ 1469 struct task_io_accounting ioac; 1470 #if defined(CONFIG_TASK_XACCT) 1471 u64 acct_rss_mem1; /* accumulated rss usage */ 1472 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1473 cputime_t acct_timexpd; /* stime + utime since last update */ 1474 #endif 1475 #ifdef CONFIG_CPUSETS 1476 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1477 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1478 int cpuset_mem_spread_rotor; 1479 int cpuset_slab_spread_rotor; 1480 #endif 1481 #ifdef CONFIG_CGROUPS 1482 /* Control Group info protected by css_set_lock */ 1483 struct css_set __rcu *cgroups; 1484 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1485 struct list_head cg_list; 1486 #endif 1487 #ifdef CONFIG_FUTEX 1488 struct robust_list_head __user *robust_list; 1489 #ifdef CONFIG_COMPAT 1490 struct compat_robust_list_head __user *compat_robust_list; 1491 #endif 1492 struct list_head pi_state_list; 1493 struct futex_pi_state *pi_state_cache; 1494 #endif 1495 #ifdef CONFIG_PERF_EVENTS 1496 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1497 struct mutex perf_event_mutex; 1498 struct list_head perf_event_list; 1499 #endif 1500 #ifdef CONFIG_NUMA 1501 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1502 short il_next; 1503 short pref_node_fork; 1504 #endif 1505 struct rcu_head rcu; 1506 1507 /* 1508 * cache last used pipe for splice 1509 */ 1510 struct pipe_inode_info *splice_pipe; 1511 #ifdef CONFIG_TASK_DELAY_ACCT 1512 struct task_delay_info *delays; 1513 #endif 1514 #ifdef CONFIG_FAULT_INJECTION 1515 int make_it_fail; 1516 #endif 1517 /* 1518 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1519 * balance_dirty_pages() for some dirty throttling pause 1520 */ 1521 int nr_dirtied; 1522 int nr_dirtied_pause; 1523 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1524 1525 #ifdef CONFIG_LATENCYTOP 1526 int latency_record_count; 1527 struct latency_record latency_record[LT_SAVECOUNT]; 1528 #endif 1529 /* 1530 * time slack values; these are used to round up poll() and 1531 * select() etc timeout values. These are in nanoseconds. 1532 */ 1533 unsigned long timer_slack_ns; 1534 unsigned long default_timer_slack_ns; 1535 1536 struct list_head *scm_work_list; 1537 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1538 /* Index of current stored address in ret_stack */ 1539 int curr_ret_stack; 1540 /* Stack of return addresses for return function tracing */ 1541 struct ftrace_ret_stack *ret_stack; 1542 /* time stamp for last schedule */ 1543 unsigned long long ftrace_timestamp; 1544 /* 1545 * Number of functions that haven't been traced 1546 * because of depth overrun. 1547 */ 1548 atomic_t trace_overrun; 1549 /* Pause for the tracing */ 1550 atomic_t tracing_graph_pause; 1551 #endif 1552 #ifdef CONFIG_TRACING 1553 /* state flags for use by tracers */ 1554 unsigned long trace; 1555 /* bitmask and counter of trace recursion */ 1556 unsigned long trace_recursion; 1557 #endif /* CONFIG_TRACING */ 1558 #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */ 1559 struct memcg_batch_info { 1560 int do_batch; /* incremented when batch uncharge started */ 1561 struct mem_cgroup *memcg; /* target memcg of uncharge */ 1562 unsigned long nr_pages; /* uncharged usage */ 1563 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ 1564 } memcg_batch; 1565 #endif 1566 #ifdef CONFIG_HAVE_HW_BREAKPOINT 1567 atomic_t ptrace_bp_refcnt; 1568 #endif 1569 #ifdef CONFIG_UPROBES 1570 struct uprobe_task *utask; 1571 int uprobe_srcu_id; 1572 #endif 1573 }; 1574 1575 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1576 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1577 1578 /* 1579 * Priority of a process goes from 0..MAX_PRIO-1, valid RT 1580 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH 1581 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority 1582 * values are inverted: lower p->prio value means higher priority. 1583 * 1584 * The MAX_USER_RT_PRIO value allows the actual maximum 1585 * RT priority to be separate from the value exported to 1586 * user-space. This allows kernel threads to set their 1587 * priority to a value higher than any user task. Note: 1588 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO. 1589 */ 1590 1591 #define MAX_USER_RT_PRIO 100 1592 #define MAX_RT_PRIO MAX_USER_RT_PRIO 1593 1594 #define MAX_PRIO (MAX_RT_PRIO + 40) 1595 #define DEFAULT_PRIO (MAX_RT_PRIO + 20) 1596 1597 static inline int rt_prio(int prio) 1598 { 1599 if (unlikely(prio < MAX_RT_PRIO)) 1600 return 1; 1601 return 0; 1602 } 1603 1604 static inline int rt_task(struct task_struct *p) 1605 { 1606 return rt_prio(p->prio); 1607 } 1608 1609 static inline struct pid *task_pid(struct task_struct *task) 1610 { 1611 return task->pids[PIDTYPE_PID].pid; 1612 } 1613 1614 static inline struct pid *task_tgid(struct task_struct *task) 1615 { 1616 return task->group_leader->pids[PIDTYPE_PID].pid; 1617 } 1618 1619 /* 1620 * Without tasklist or rcu lock it is not safe to dereference 1621 * the result of task_pgrp/task_session even if task == current, 1622 * we can race with another thread doing sys_setsid/sys_setpgid. 1623 */ 1624 static inline struct pid *task_pgrp(struct task_struct *task) 1625 { 1626 return task->group_leader->pids[PIDTYPE_PGID].pid; 1627 } 1628 1629 static inline struct pid *task_session(struct task_struct *task) 1630 { 1631 return task->group_leader->pids[PIDTYPE_SID].pid; 1632 } 1633 1634 struct pid_namespace; 1635 1636 /* 1637 * the helpers to get the task's different pids as they are seen 1638 * from various namespaces 1639 * 1640 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1641 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1642 * current. 1643 * task_xid_nr_ns() : id seen from the ns specified; 1644 * 1645 * set_task_vxid() : assigns a virtual id to a task; 1646 * 1647 * see also pid_nr() etc in include/linux/pid.h 1648 */ 1649 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1650 struct pid_namespace *ns); 1651 1652 static inline pid_t task_pid_nr(struct task_struct *tsk) 1653 { 1654 return tsk->pid; 1655 } 1656 1657 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1658 struct pid_namespace *ns) 1659 { 1660 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1661 } 1662 1663 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1664 { 1665 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1666 } 1667 1668 1669 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1670 { 1671 return tsk->tgid; 1672 } 1673 1674 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1675 1676 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1677 { 1678 return pid_vnr(task_tgid(tsk)); 1679 } 1680 1681 1682 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1683 struct pid_namespace *ns) 1684 { 1685 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1686 } 1687 1688 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1689 { 1690 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1691 } 1692 1693 1694 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1695 struct pid_namespace *ns) 1696 { 1697 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1698 } 1699 1700 static inline pid_t task_session_vnr(struct task_struct *tsk) 1701 { 1702 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1703 } 1704 1705 /* obsolete, do not use */ 1706 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1707 { 1708 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1709 } 1710 1711 /** 1712 * pid_alive - check that a task structure is not stale 1713 * @p: Task structure to be checked. 1714 * 1715 * Test if a process is not yet dead (at most zombie state) 1716 * If pid_alive fails, then pointers within the task structure 1717 * can be stale and must not be dereferenced. 1718 */ 1719 static inline int pid_alive(struct task_struct *p) 1720 { 1721 return p->pids[PIDTYPE_PID].pid != NULL; 1722 } 1723 1724 /** 1725 * is_global_init - check if a task structure is init 1726 * @tsk: Task structure to be checked. 1727 * 1728 * Check if a task structure is the first user space task the kernel created. 1729 */ 1730 static inline int is_global_init(struct task_struct *tsk) 1731 { 1732 return tsk->pid == 1; 1733 } 1734 1735 /* 1736 * is_container_init: 1737 * check whether in the task is init in its own pid namespace. 1738 */ 1739 extern int is_container_init(struct task_struct *tsk); 1740 1741 extern struct pid *cad_pid; 1742 1743 extern void free_task(struct task_struct *tsk); 1744 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1745 1746 extern void __put_task_struct(struct task_struct *t); 1747 1748 static inline void put_task_struct(struct task_struct *t) 1749 { 1750 if (atomic_dec_and_test(&t->usage)) 1751 __put_task_struct(t); 1752 } 1753 1754 extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st); 1755 extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st); 1756 1757 /* 1758 * Per process flags 1759 */ 1760 #define PF_EXITING 0x00000004 /* getting shut down */ 1761 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1762 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 1763 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1764 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1765 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 1766 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1767 #define PF_DUMPCORE 0x00000200 /* dumped core */ 1768 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 1769 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1770 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 1771 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1772 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1773 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1774 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1775 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 1776 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1777 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1778 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1779 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1780 #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ 1781 #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ 1782 #define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */ 1783 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1784 #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ 1785 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1786 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1787 1788 /* 1789 * Only the _current_ task can read/write to tsk->flags, but other 1790 * tasks can access tsk->flags in readonly mode for example 1791 * with tsk_used_math (like during threaded core dumping). 1792 * There is however an exception to this rule during ptrace 1793 * or during fork: the ptracer task is allowed to write to the 1794 * child->flags of its traced child (same goes for fork, the parent 1795 * can write to the child->flags), because we're guaranteed the 1796 * child is not running and in turn not changing child->flags 1797 * at the same time the parent does it. 1798 */ 1799 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1800 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1801 #define clear_used_math() clear_stopped_child_used_math(current) 1802 #define set_used_math() set_stopped_child_used_math(current) 1803 #define conditional_stopped_child_used_math(condition, child) \ 1804 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1805 #define conditional_used_math(condition) \ 1806 conditional_stopped_child_used_math(condition, current) 1807 #define copy_to_stopped_child_used_math(child) \ 1808 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1809 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1810 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1811 #define used_math() tsk_used_math(current) 1812 1813 /* 1814 * task->jobctl flags 1815 */ 1816 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 1817 1818 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 1819 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 1820 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 1821 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 1822 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 1823 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 1824 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 1825 1826 #define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) 1827 #define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) 1828 #define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) 1829 #define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) 1830 #define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) 1831 #define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) 1832 #define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) 1833 1834 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 1835 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 1836 1837 extern bool task_set_jobctl_pending(struct task_struct *task, 1838 unsigned int mask); 1839 extern void task_clear_jobctl_trapping(struct task_struct *task); 1840 extern void task_clear_jobctl_pending(struct task_struct *task, 1841 unsigned int mask); 1842 1843 #ifdef CONFIG_PREEMPT_RCU 1844 1845 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */ 1846 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */ 1847 1848 static inline void rcu_copy_process(struct task_struct *p) 1849 { 1850 p->rcu_read_lock_nesting = 0; 1851 p->rcu_read_unlock_special = 0; 1852 #ifdef CONFIG_TREE_PREEMPT_RCU 1853 p->rcu_blocked_node = NULL; 1854 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1855 #ifdef CONFIG_RCU_BOOST 1856 p->rcu_boost_mutex = NULL; 1857 #endif /* #ifdef CONFIG_RCU_BOOST */ 1858 INIT_LIST_HEAD(&p->rcu_node_entry); 1859 } 1860 1861 static inline void rcu_switch_from(struct task_struct *prev) 1862 { 1863 if (prev->rcu_read_lock_nesting != 0) 1864 rcu_preempt_note_context_switch(); 1865 } 1866 1867 #else 1868 1869 static inline void rcu_copy_process(struct task_struct *p) 1870 { 1871 } 1872 1873 static inline void rcu_switch_from(struct task_struct *prev) 1874 { 1875 } 1876 1877 #endif 1878 1879 #ifdef CONFIG_SMP 1880 extern void do_set_cpus_allowed(struct task_struct *p, 1881 const struct cpumask *new_mask); 1882 1883 extern int set_cpus_allowed_ptr(struct task_struct *p, 1884 const struct cpumask *new_mask); 1885 #else 1886 static inline void do_set_cpus_allowed(struct task_struct *p, 1887 const struct cpumask *new_mask) 1888 { 1889 } 1890 static inline int set_cpus_allowed_ptr(struct task_struct *p, 1891 const struct cpumask *new_mask) 1892 { 1893 if (!cpumask_test_cpu(0, new_mask)) 1894 return -EINVAL; 1895 return 0; 1896 } 1897 #endif 1898 1899 #ifndef CONFIG_CPUMASK_OFFSTACK 1900 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 1901 { 1902 return set_cpus_allowed_ptr(p, &new_mask); 1903 } 1904 #endif 1905 1906 /* 1907 * Do not use outside of architecture code which knows its limitations. 1908 * 1909 * sched_clock() has no promise of monotonicity or bounded drift between 1910 * CPUs, use (which you should not) requires disabling IRQs. 1911 * 1912 * Please use one of the three interfaces below. 1913 */ 1914 extern unsigned long long notrace sched_clock(void); 1915 /* 1916 * See the comment in kernel/sched/clock.c 1917 */ 1918 extern u64 cpu_clock(int cpu); 1919 extern u64 local_clock(void); 1920 extern u64 sched_clock_cpu(int cpu); 1921 1922 1923 extern void sched_clock_init(void); 1924 1925 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 1926 static inline void sched_clock_tick(void) 1927 { 1928 } 1929 1930 static inline void sched_clock_idle_sleep_event(void) 1931 { 1932 } 1933 1934 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 1935 { 1936 } 1937 #else 1938 /* 1939 * Architectures can set this to 1 if they have specified 1940 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 1941 * but then during bootup it turns out that sched_clock() 1942 * is reliable after all: 1943 */ 1944 extern int sched_clock_stable; 1945 1946 extern void sched_clock_tick(void); 1947 extern void sched_clock_idle_sleep_event(void); 1948 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1949 #endif 1950 1951 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1952 /* 1953 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 1954 * The reason for this explicit opt-in is not to have perf penalty with 1955 * slow sched_clocks. 1956 */ 1957 extern void enable_sched_clock_irqtime(void); 1958 extern void disable_sched_clock_irqtime(void); 1959 #else 1960 static inline void enable_sched_clock_irqtime(void) {} 1961 static inline void disable_sched_clock_irqtime(void) {} 1962 #endif 1963 1964 extern unsigned long long 1965 task_sched_runtime(struct task_struct *task); 1966 1967 /* sched_exec is called by processes performing an exec */ 1968 #ifdef CONFIG_SMP 1969 extern void sched_exec(void); 1970 #else 1971 #define sched_exec() {} 1972 #endif 1973 1974 extern void sched_clock_idle_sleep_event(void); 1975 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1976 1977 #ifdef CONFIG_HOTPLUG_CPU 1978 extern void idle_task_exit(void); 1979 #else 1980 static inline void idle_task_exit(void) {} 1981 #endif 1982 1983 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP) 1984 extern void wake_up_idle_cpu(int cpu); 1985 #else 1986 static inline void wake_up_idle_cpu(int cpu) { } 1987 #endif 1988 1989 extern unsigned int sysctl_sched_latency; 1990 extern unsigned int sysctl_sched_min_granularity; 1991 extern unsigned int sysctl_sched_wakeup_granularity; 1992 extern unsigned int sysctl_sched_child_runs_first; 1993 1994 enum sched_tunable_scaling { 1995 SCHED_TUNABLESCALING_NONE, 1996 SCHED_TUNABLESCALING_LOG, 1997 SCHED_TUNABLESCALING_LINEAR, 1998 SCHED_TUNABLESCALING_END, 1999 }; 2000 extern enum sched_tunable_scaling sysctl_sched_tunable_scaling; 2001 2002 #ifdef CONFIG_SCHED_DEBUG 2003 extern unsigned int sysctl_sched_migration_cost; 2004 extern unsigned int sysctl_sched_nr_migrate; 2005 extern unsigned int sysctl_sched_time_avg; 2006 extern unsigned int sysctl_timer_migration; 2007 extern unsigned int sysctl_sched_shares_window; 2008 2009 int sched_proc_update_handler(struct ctl_table *table, int write, 2010 void __user *buffer, size_t *length, 2011 loff_t *ppos); 2012 #endif 2013 #ifdef CONFIG_SCHED_DEBUG 2014 static inline unsigned int get_sysctl_timer_migration(void) 2015 { 2016 return sysctl_timer_migration; 2017 } 2018 #else 2019 static inline unsigned int get_sysctl_timer_migration(void) 2020 { 2021 return 1; 2022 } 2023 #endif 2024 extern unsigned int sysctl_sched_rt_period; 2025 extern int sysctl_sched_rt_runtime; 2026 2027 int sched_rt_handler(struct ctl_table *table, int write, 2028 void __user *buffer, size_t *lenp, 2029 loff_t *ppos); 2030 2031 #ifdef CONFIG_SCHED_AUTOGROUP 2032 extern unsigned int sysctl_sched_autogroup_enabled; 2033 2034 extern void sched_autogroup_create_attach(struct task_struct *p); 2035 extern void sched_autogroup_detach(struct task_struct *p); 2036 extern void sched_autogroup_fork(struct signal_struct *sig); 2037 extern void sched_autogroup_exit(struct signal_struct *sig); 2038 #ifdef CONFIG_PROC_FS 2039 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2040 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2041 #endif 2042 #else 2043 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2044 static inline void sched_autogroup_detach(struct task_struct *p) { } 2045 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2046 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2047 #endif 2048 2049 #ifdef CONFIG_CFS_BANDWIDTH 2050 extern unsigned int sysctl_sched_cfs_bandwidth_slice; 2051 #endif 2052 2053 #ifdef CONFIG_RT_MUTEXES 2054 extern int rt_mutex_getprio(struct task_struct *p); 2055 extern void rt_mutex_setprio(struct task_struct *p, int prio); 2056 extern void rt_mutex_adjust_pi(struct task_struct *p); 2057 static inline bool tsk_is_pi_blocked(struct task_struct *tsk) 2058 { 2059 return tsk->pi_blocked_on != NULL; 2060 } 2061 #else 2062 static inline int rt_mutex_getprio(struct task_struct *p) 2063 { 2064 return p->normal_prio; 2065 } 2066 # define rt_mutex_adjust_pi(p) do { } while (0) 2067 static inline bool tsk_is_pi_blocked(struct task_struct *tsk) 2068 { 2069 return false; 2070 } 2071 #endif 2072 2073 extern bool yield_to(struct task_struct *p, bool preempt); 2074 extern void set_user_nice(struct task_struct *p, long nice); 2075 extern int task_prio(const struct task_struct *p); 2076 extern int task_nice(const struct task_struct *p); 2077 extern int can_nice(const struct task_struct *p, const int nice); 2078 extern int task_curr(const struct task_struct *p); 2079 extern int idle_cpu(int cpu); 2080 extern int sched_setscheduler(struct task_struct *, int, 2081 const struct sched_param *); 2082 extern int sched_setscheduler_nocheck(struct task_struct *, int, 2083 const struct sched_param *); 2084 extern struct task_struct *idle_task(int cpu); 2085 /** 2086 * is_idle_task - is the specified task an idle task? 2087 * @p: the task in question. 2088 */ 2089 static inline bool is_idle_task(const struct task_struct *p) 2090 { 2091 return p->pid == 0; 2092 } 2093 extern struct task_struct *curr_task(int cpu); 2094 extern void set_curr_task(int cpu, struct task_struct *p); 2095 2096 void yield(void); 2097 2098 /* 2099 * The default (Linux) execution domain. 2100 */ 2101 extern struct exec_domain default_exec_domain; 2102 2103 union thread_union { 2104 struct thread_info thread_info; 2105 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2106 }; 2107 2108 #ifndef __HAVE_ARCH_KSTACK_END 2109 static inline int kstack_end(void *addr) 2110 { 2111 /* Reliable end of stack detection: 2112 * Some APM bios versions misalign the stack 2113 */ 2114 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2115 } 2116 #endif 2117 2118 extern union thread_union init_thread_union; 2119 extern struct task_struct init_task; 2120 2121 extern struct mm_struct init_mm; 2122 2123 extern struct pid_namespace init_pid_ns; 2124 2125 /* 2126 * find a task by one of its numerical ids 2127 * 2128 * find_task_by_pid_ns(): 2129 * finds a task by its pid in the specified namespace 2130 * find_task_by_vpid(): 2131 * finds a task by its virtual pid 2132 * 2133 * see also find_vpid() etc in include/linux/pid.h 2134 */ 2135 2136 extern struct task_struct *find_task_by_vpid(pid_t nr); 2137 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2138 struct pid_namespace *ns); 2139 2140 extern void __set_special_pids(struct pid *pid); 2141 2142 /* per-UID process charging. */ 2143 extern struct user_struct * alloc_uid(kuid_t); 2144 static inline struct user_struct *get_uid(struct user_struct *u) 2145 { 2146 atomic_inc(&u->__count); 2147 return u; 2148 } 2149 extern void free_uid(struct user_struct *); 2150 2151 #include <asm/current.h> 2152 2153 extern void xtime_update(unsigned long ticks); 2154 2155 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2156 extern int wake_up_process(struct task_struct *tsk); 2157 extern void wake_up_new_task(struct task_struct *tsk); 2158 #ifdef CONFIG_SMP 2159 extern void kick_process(struct task_struct *tsk); 2160 #else 2161 static inline void kick_process(struct task_struct *tsk) { } 2162 #endif 2163 extern void sched_fork(struct task_struct *p); 2164 extern void sched_dead(struct task_struct *p); 2165 2166 extern void proc_caches_init(void); 2167 extern void flush_signals(struct task_struct *); 2168 extern void __flush_signals(struct task_struct *); 2169 extern void ignore_signals(struct task_struct *); 2170 extern void flush_signal_handlers(struct task_struct *, int force_default); 2171 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2172 2173 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2174 { 2175 unsigned long flags; 2176 int ret; 2177 2178 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2179 ret = dequeue_signal(tsk, mask, info); 2180 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2181 2182 return ret; 2183 } 2184 2185 extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2186 sigset_t *mask); 2187 extern void unblock_all_signals(void); 2188 extern void release_task(struct task_struct * p); 2189 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2190 extern int force_sigsegv(int, struct task_struct *); 2191 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2192 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2193 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2194 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2195 const struct cred *, u32); 2196 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2197 extern int kill_pid(struct pid *pid, int sig, int priv); 2198 extern int kill_proc_info(int, struct siginfo *, pid_t); 2199 extern __must_check bool do_notify_parent(struct task_struct *, int); 2200 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2201 extern void force_sig(int, struct task_struct *); 2202 extern int send_sig(int, struct task_struct *, int); 2203 extern int zap_other_threads(struct task_struct *p); 2204 extern struct sigqueue *sigqueue_alloc(void); 2205 extern void sigqueue_free(struct sigqueue *); 2206 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2207 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2208 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long); 2209 2210 static inline void restore_saved_sigmask(void) 2211 { 2212 if (test_and_clear_restore_sigmask()) 2213 __set_current_blocked(¤t->saved_sigmask); 2214 } 2215 2216 static inline sigset_t *sigmask_to_save(void) 2217 { 2218 sigset_t *res = ¤t->blocked; 2219 if (unlikely(test_restore_sigmask())) 2220 res = ¤t->saved_sigmask; 2221 return res; 2222 } 2223 2224 static inline int kill_cad_pid(int sig, int priv) 2225 { 2226 return kill_pid(cad_pid, sig, priv); 2227 } 2228 2229 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2230 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2231 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2232 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2233 2234 /* 2235 * True if we are on the alternate signal stack. 2236 */ 2237 static inline int on_sig_stack(unsigned long sp) 2238 { 2239 #ifdef CONFIG_STACK_GROWSUP 2240 return sp >= current->sas_ss_sp && 2241 sp - current->sas_ss_sp < current->sas_ss_size; 2242 #else 2243 return sp > current->sas_ss_sp && 2244 sp - current->sas_ss_sp <= current->sas_ss_size; 2245 #endif 2246 } 2247 2248 static inline int sas_ss_flags(unsigned long sp) 2249 { 2250 return (current->sas_ss_size == 0 ? SS_DISABLE 2251 : on_sig_stack(sp) ? SS_ONSTACK : 0); 2252 } 2253 2254 /* 2255 * Routines for handling mm_structs 2256 */ 2257 extern struct mm_struct * mm_alloc(void); 2258 2259 /* mmdrop drops the mm and the page tables */ 2260 extern void __mmdrop(struct mm_struct *); 2261 static inline void mmdrop(struct mm_struct * mm) 2262 { 2263 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2264 __mmdrop(mm); 2265 } 2266 2267 /* mmput gets rid of the mappings and all user-space */ 2268 extern void mmput(struct mm_struct *); 2269 /* Grab a reference to a task's mm, if it is not already going away */ 2270 extern struct mm_struct *get_task_mm(struct task_struct *task); 2271 /* 2272 * Grab a reference to a task's mm, if it is not already going away 2273 * and ptrace_may_access with the mode parameter passed to it 2274 * succeeds. 2275 */ 2276 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2277 /* Remove the current tasks stale references to the old mm_struct */ 2278 extern void mm_release(struct task_struct *, struct mm_struct *); 2279 /* Allocate a new mm structure and copy contents from tsk->mm */ 2280 extern struct mm_struct *dup_mm(struct task_struct *tsk); 2281 2282 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2283 struct task_struct *, struct pt_regs *); 2284 extern void flush_thread(void); 2285 extern void exit_thread(void); 2286 2287 extern void exit_files(struct task_struct *); 2288 extern void __cleanup_sighand(struct sighand_struct *); 2289 2290 extern void exit_itimers(struct signal_struct *); 2291 extern void flush_itimer_signals(void); 2292 2293 extern void do_group_exit(int); 2294 2295 extern void daemonize(const char *, ...); 2296 extern int allow_signal(int); 2297 extern int disallow_signal(int); 2298 2299 extern int do_execve(const char *, 2300 const char __user * const __user *, 2301 const char __user * const __user *, struct pt_regs *); 2302 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *); 2303 struct task_struct *fork_idle(int); 2304 2305 extern void set_task_comm(struct task_struct *tsk, char *from); 2306 extern char *get_task_comm(char *to, struct task_struct *tsk); 2307 2308 #ifdef CONFIG_SMP 2309 void scheduler_ipi(void); 2310 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2311 #else 2312 static inline void scheduler_ipi(void) { } 2313 static inline unsigned long wait_task_inactive(struct task_struct *p, 2314 long match_state) 2315 { 2316 return 1; 2317 } 2318 #endif 2319 2320 #define next_task(p) \ 2321 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2322 2323 #define for_each_process(p) \ 2324 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2325 2326 extern bool current_is_single_threaded(void); 2327 2328 /* 2329 * Careful: do_each_thread/while_each_thread is a double loop so 2330 * 'break' will not work as expected - use goto instead. 2331 */ 2332 #define do_each_thread(g, t) \ 2333 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2334 2335 #define while_each_thread(g, t) \ 2336 while ((t = next_thread(t)) != g) 2337 2338 static inline int get_nr_threads(struct task_struct *tsk) 2339 { 2340 return tsk->signal->nr_threads; 2341 } 2342 2343 static inline bool thread_group_leader(struct task_struct *p) 2344 { 2345 return p->exit_signal >= 0; 2346 } 2347 2348 /* Do to the insanities of de_thread it is possible for a process 2349 * to have the pid of the thread group leader without actually being 2350 * the thread group leader. For iteration through the pids in proc 2351 * all we care about is that we have a task with the appropriate 2352 * pid, we don't actually care if we have the right task. 2353 */ 2354 static inline int has_group_leader_pid(struct task_struct *p) 2355 { 2356 return p->pid == p->tgid; 2357 } 2358 2359 static inline 2360 int same_thread_group(struct task_struct *p1, struct task_struct *p2) 2361 { 2362 return p1->tgid == p2->tgid; 2363 } 2364 2365 static inline struct task_struct *next_thread(const struct task_struct *p) 2366 { 2367 return list_entry_rcu(p->thread_group.next, 2368 struct task_struct, thread_group); 2369 } 2370 2371 static inline int thread_group_empty(struct task_struct *p) 2372 { 2373 return list_empty(&p->thread_group); 2374 } 2375 2376 #define delay_group_leader(p) \ 2377 (thread_group_leader(p) && !thread_group_empty(p)) 2378 2379 /* 2380 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2381 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2382 * pins the final release of task.io_context. Also protects ->cpuset and 2383 * ->cgroup.subsys[]. And ->vfork_done. 2384 * 2385 * Nests both inside and outside of read_lock(&tasklist_lock). 2386 * It must not be nested with write_lock_irq(&tasklist_lock), 2387 * neither inside nor outside. 2388 */ 2389 static inline void task_lock(struct task_struct *p) 2390 { 2391 spin_lock(&p->alloc_lock); 2392 } 2393 2394 static inline void task_unlock(struct task_struct *p) 2395 { 2396 spin_unlock(&p->alloc_lock); 2397 } 2398 2399 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2400 unsigned long *flags); 2401 2402 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2403 unsigned long *flags) 2404 { 2405 struct sighand_struct *ret; 2406 2407 ret = __lock_task_sighand(tsk, flags); 2408 (void)__cond_lock(&tsk->sighand->siglock, ret); 2409 return ret; 2410 } 2411 2412 static inline void unlock_task_sighand(struct task_struct *tsk, 2413 unsigned long *flags) 2414 { 2415 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2416 } 2417 2418 #ifdef CONFIG_CGROUPS 2419 static inline void threadgroup_change_begin(struct task_struct *tsk) 2420 { 2421 down_read(&tsk->signal->group_rwsem); 2422 } 2423 static inline void threadgroup_change_end(struct task_struct *tsk) 2424 { 2425 up_read(&tsk->signal->group_rwsem); 2426 } 2427 2428 /** 2429 * threadgroup_lock - lock threadgroup 2430 * @tsk: member task of the threadgroup to lock 2431 * 2432 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter 2433 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or 2434 * perform exec. This is useful for cases where the threadgroup needs to 2435 * stay stable across blockable operations. 2436 * 2437 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for 2438 * synchronization. While held, no new task will be added to threadgroup 2439 * and no existing live task will have its PF_EXITING set. 2440 * 2441 * During exec, a task goes and puts its thread group through unusual 2442 * changes. After de-threading, exclusive access is assumed to resources 2443 * which are usually shared by tasks in the same group - e.g. sighand may 2444 * be replaced with a new one. Also, the exec'ing task takes over group 2445 * leader role including its pid. Exclude these changes while locked by 2446 * grabbing cred_guard_mutex which is used to synchronize exec path. 2447 */ 2448 static inline void threadgroup_lock(struct task_struct *tsk) 2449 { 2450 /* 2451 * exec uses exit for de-threading nesting group_rwsem inside 2452 * cred_guard_mutex. Grab cred_guard_mutex first. 2453 */ 2454 mutex_lock(&tsk->signal->cred_guard_mutex); 2455 down_write(&tsk->signal->group_rwsem); 2456 } 2457 2458 /** 2459 * threadgroup_unlock - unlock threadgroup 2460 * @tsk: member task of the threadgroup to unlock 2461 * 2462 * Reverse threadgroup_lock(). 2463 */ 2464 static inline void threadgroup_unlock(struct task_struct *tsk) 2465 { 2466 up_write(&tsk->signal->group_rwsem); 2467 mutex_unlock(&tsk->signal->cred_guard_mutex); 2468 } 2469 #else 2470 static inline void threadgroup_change_begin(struct task_struct *tsk) {} 2471 static inline void threadgroup_change_end(struct task_struct *tsk) {} 2472 static inline void threadgroup_lock(struct task_struct *tsk) {} 2473 static inline void threadgroup_unlock(struct task_struct *tsk) {} 2474 #endif 2475 2476 #ifndef __HAVE_THREAD_FUNCTIONS 2477 2478 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 2479 #define task_stack_page(task) ((task)->stack) 2480 2481 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2482 { 2483 *task_thread_info(p) = *task_thread_info(org); 2484 task_thread_info(p)->task = p; 2485 } 2486 2487 static inline unsigned long *end_of_stack(struct task_struct *p) 2488 { 2489 return (unsigned long *)(task_thread_info(p) + 1); 2490 } 2491 2492 #endif 2493 2494 static inline int object_is_on_stack(void *obj) 2495 { 2496 void *stack = task_stack_page(current); 2497 2498 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2499 } 2500 2501 extern void thread_info_cache_init(void); 2502 2503 #ifdef CONFIG_DEBUG_STACK_USAGE 2504 static inline unsigned long stack_not_used(struct task_struct *p) 2505 { 2506 unsigned long *n = end_of_stack(p); 2507 2508 do { /* Skip over canary */ 2509 n++; 2510 } while (!*n); 2511 2512 return (unsigned long)n - (unsigned long)end_of_stack(p); 2513 } 2514 #endif 2515 2516 /* set thread flags in other task's structures 2517 * - see asm/thread_info.h for TIF_xxxx flags available 2518 */ 2519 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2520 { 2521 set_ti_thread_flag(task_thread_info(tsk), flag); 2522 } 2523 2524 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2525 { 2526 clear_ti_thread_flag(task_thread_info(tsk), flag); 2527 } 2528 2529 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2530 { 2531 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2532 } 2533 2534 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2535 { 2536 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2537 } 2538 2539 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2540 { 2541 return test_ti_thread_flag(task_thread_info(tsk), flag); 2542 } 2543 2544 static inline void set_tsk_need_resched(struct task_struct *tsk) 2545 { 2546 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2547 } 2548 2549 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2550 { 2551 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2552 } 2553 2554 static inline int test_tsk_need_resched(struct task_struct *tsk) 2555 { 2556 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2557 } 2558 2559 static inline int restart_syscall(void) 2560 { 2561 set_tsk_thread_flag(current, TIF_SIGPENDING); 2562 return -ERESTARTNOINTR; 2563 } 2564 2565 static inline int signal_pending(struct task_struct *p) 2566 { 2567 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2568 } 2569 2570 static inline int __fatal_signal_pending(struct task_struct *p) 2571 { 2572 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2573 } 2574 2575 static inline int fatal_signal_pending(struct task_struct *p) 2576 { 2577 return signal_pending(p) && __fatal_signal_pending(p); 2578 } 2579 2580 static inline int signal_pending_state(long state, struct task_struct *p) 2581 { 2582 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2583 return 0; 2584 if (!signal_pending(p)) 2585 return 0; 2586 2587 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2588 } 2589 2590 static inline int need_resched(void) 2591 { 2592 return unlikely(test_thread_flag(TIF_NEED_RESCHED)); 2593 } 2594 2595 /* 2596 * cond_resched() and cond_resched_lock(): latency reduction via 2597 * explicit rescheduling in places that are safe. The return 2598 * value indicates whether a reschedule was done in fact. 2599 * cond_resched_lock() will drop the spinlock before scheduling, 2600 * cond_resched_softirq() will enable bhs before scheduling. 2601 */ 2602 extern int _cond_resched(void); 2603 2604 #define cond_resched() ({ \ 2605 __might_sleep(__FILE__, __LINE__, 0); \ 2606 _cond_resched(); \ 2607 }) 2608 2609 extern int __cond_resched_lock(spinlock_t *lock); 2610 2611 #ifdef CONFIG_PREEMPT_COUNT 2612 #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2613 #else 2614 #define PREEMPT_LOCK_OFFSET 0 2615 #endif 2616 2617 #define cond_resched_lock(lock) ({ \ 2618 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2619 __cond_resched_lock(lock); \ 2620 }) 2621 2622 extern int __cond_resched_softirq(void); 2623 2624 #define cond_resched_softirq() ({ \ 2625 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2626 __cond_resched_softirq(); \ 2627 }) 2628 2629 /* 2630 * Does a critical section need to be broken due to another 2631 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2632 * but a general need for low latency) 2633 */ 2634 static inline int spin_needbreak(spinlock_t *lock) 2635 { 2636 #ifdef CONFIG_PREEMPT 2637 return spin_is_contended(lock); 2638 #else 2639 return 0; 2640 #endif 2641 } 2642 2643 /* 2644 * Thread group CPU time accounting. 2645 */ 2646 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 2647 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 2648 2649 static inline void thread_group_cputime_init(struct signal_struct *sig) 2650 { 2651 raw_spin_lock_init(&sig->cputimer.lock); 2652 } 2653 2654 /* 2655 * Reevaluate whether the task has signals pending delivery. 2656 * Wake the task if so. 2657 * This is required every time the blocked sigset_t changes. 2658 * callers must hold sighand->siglock. 2659 */ 2660 extern void recalc_sigpending_and_wake(struct task_struct *t); 2661 extern void recalc_sigpending(void); 2662 2663 extern void signal_wake_up(struct task_struct *t, int resume_stopped); 2664 2665 /* 2666 * Wrappers for p->thread_info->cpu access. No-op on UP. 2667 */ 2668 #ifdef CONFIG_SMP 2669 2670 static inline unsigned int task_cpu(const struct task_struct *p) 2671 { 2672 return task_thread_info(p)->cpu; 2673 } 2674 2675 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2676 2677 #else 2678 2679 static inline unsigned int task_cpu(const struct task_struct *p) 2680 { 2681 return 0; 2682 } 2683 2684 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2685 { 2686 } 2687 2688 #endif /* CONFIG_SMP */ 2689 2690 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2691 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2692 2693 extern void normalize_rt_tasks(void); 2694 2695 #ifdef CONFIG_CGROUP_SCHED 2696 2697 extern struct task_group root_task_group; 2698 2699 extern struct task_group *sched_create_group(struct task_group *parent); 2700 extern void sched_destroy_group(struct task_group *tg); 2701 extern void sched_move_task(struct task_struct *tsk); 2702 #ifdef CONFIG_FAIR_GROUP_SCHED 2703 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 2704 extern unsigned long sched_group_shares(struct task_group *tg); 2705 #endif 2706 #ifdef CONFIG_RT_GROUP_SCHED 2707 extern int sched_group_set_rt_runtime(struct task_group *tg, 2708 long rt_runtime_us); 2709 extern long sched_group_rt_runtime(struct task_group *tg); 2710 extern int sched_group_set_rt_period(struct task_group *tg, 2711 long rt_period_us); 2712 extern long sched_group_rt_period(struct task_group *tg); 2713 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 2714 #endif 2715 #endif 2716 2717 extern int task_can_switch_user(struct user_struct *up, 2718 struct task_struct *tsk); 2719 2720 #ifdef CONFIG_TASK_XACCT 2721 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2722 { 2723 tsk->ioac.rchar += amt; 2724 } 2725 2726 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2727 { 2728 tsk->ioac.wchar += amt; 2729 } 2730 2731 static inline void inc_syscr(struct task_struct *tsk) 2732 { 2733 tsk->ioac.syscr++; 2734 } 2735 2736 static inline void inc_syscw(struct task_struct *tsk) 2737 { 2738 tsk->ioac.syscw++; 2739 } 2740 #else 2741 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2742 { 2743 } 2744 2745 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2746 { 2747 } 2748 2749 static inline void inc_syscr(struct task_struct *tsk) 2750 { 2751 } 2752 2753 static inline void inc_syscw(struct task_struct *tsk) 2754 { 2755 } 2756 #endif 2757 2758 #ifndef TASK_SIZE_OF 2759 #define TASK_SIZE_OF(tsk) TASK_SIZE 2760 #endif 2761 2762 #ifdef CONFIG_MM_OWNER 2763 extern void mm_update_next_owner(struct mm_struct *mm); 2764 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); 2765 #else 2766 static inline void mm_update_next_owner(struct mm_struct *mm) 2767 { 2768 } 2769 2770 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) 2771 { 2772 } 2773 #endif /* CONFIG_MM_OWNER */ 2774 2775 static inline unsigned long task_rlimit(const struct task_struct *tsk, 2776 unsigned int limit) 2777 { 2778 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); 2779 } 2780 2781 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 2782 unsigned int limit) 2783 { 2784 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); 2785 } 2786 2787 static inline unsigned long rlimit(unsigned int limit) 2788 { 2789 return task_rlimit(current, limit); 2790 } 2791 2792 static inline unsigned long rlimit_max(unsigned int limit) 2793 { 2794 return task_rlimit_max(current, limit); 2795 } 2796 2797 #endif /* __KERNEL__ */ 2798 2799 #endif 2800