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1#ifndef _LINUX_SCHED_H 2#define _LINUX_SCHED_H 3 4#include <linux/auxvec.h> /* For AT_VECTOR_SIZE */ 5 6/* 7 * cloning flags: 8 */ 9#define CSIGNAL 0x000000ff /* signal mask to be sent at exit */ 10#define CLONE_VM 0x00000100 /* set if VM shared between processes */ 11#define CLONE_FS 0x00000200 /* set if fs info shared between processes */ 12#define CLONE_FILES 0x00000400 /* set if open files shared between processes */ 13#define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */ 14#define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */ 15#define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */ 16#define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */ 17#define CLONE_THREAD 0x00010000 /* Same thread group? */ 18#define CLONE_NEWNS 0x00020000 /* New namespace group? */ 19#define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */ 20#define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */ 21#define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */ 22#define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */ 23#define CLONE_DETACHED 0x00400000 /* Unused, ignored */ 24#define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */ 25#define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */ 26#define CLONE_STOPPED 0x02000000 /* Start in stopped state */ 27#define CLONE_NEWUTS 0x04000000 /* New utsname group? */ 28#define CLONE_NEWIPC 0x08000000 /* New ipcs */ 29#define CLONE_NEWUSER 0x10000000 /* New user namespace */ 30 31/* 32 * Scheduling policies 33 */ 34#define SCHED_NORMAL 0 35#define SCHED_FIFO 1 36#define SCHED_RR 2 37#define SCHED_BATCH 3 38/* SCHED_ISO: reserved but not implemented yet */ 39#define SCHED_IDLE 5 40 41#ifdef __KERNEL__ 42 43struct sched_param { 44 int sched_priority; 45}; 46 47#include <asm/param.h> /* for HZ */ 48 49#include <linux/capability.h> 50#include <linux/threads.h> 51#include <linux/kernel.h> 52#include <linux/types.h> 53#include <linux/timex.h> 54#include <linux/jiffies.h> 55#include <linux/rbtree.h> 56#include <linux/thread_info.h> 57#include <linux/cpumask.h> 58#include <linux/errno.h> 59#include <linux/nodemask.h> 60 61#include <asm/system.h> 62#include <asm/semaphore.h> 63#include <asm/page.h> 64#include <asm/ptrace.h> 65#include <asm/mmu.h> 66#include <asm/cputime.h> 67 68#include <linux/smp.h> 69#include <linux/sem.h> 70#include <linux/signal.h> 71#include <linux/securebits.h> 72#include <linux/fs_struct.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/seccomp.h> 79#include <linux/rcupdate.h> 80#include <linux/futex.h> 81#include <linux/rtmutex.h> 82 83#include <linux/time.h> 84#include <linux/param.h> 85#include <linux/resource.h> 86#include <linux/timer.h> 87#include <linux/hrtimer.h> 88#include <linux/task_io_accounting.h> 89 90#include <asm/processor.h> 91 92struct exec_domain; 93struct futex_pi_state; 94struct bio; 95 96/* 97 * List of flags we want to share for kernel threads, 98 * if only because they are not used by them anyway. 99 */ 100#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND) 101 102/* 103 * These are the constant used to fake the fixed-point load-average 104 * counting. Some notes: 105 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 106 * a load-average precision of 10 bits integer + 11 bits fractional 107 * - if you want to count load-averages more often, you need more 108 * precision, or rounding will get you. With 2-second counting freq, 109 * the EXP_n values would be 1981, 2034 and 2043 if still using only 110 * 11 bit fractions. 111 */ 112extern unsigned long avenrun[]; /* Load averages */ 113 114#define FSHIFT 11 /* nr of bits of precision */ 115#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 116#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 117#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 118#define EXP_5 2014 /* 1/exp(5sec/5min) */ 119#define EXP_15 2037 /* 1/exp(5sec/15min) */ 120 121#define CALC_LOAD(load,exp,n) \ 122 load *= exp; \ 123 load += n*(FIXED_1-exp); \ 124 load >>= FSHIFT; 125 126extern unsigned long total_forks; 127extern int nr_threads; 128DECLARE_PER_CPU(unsigned long, process_counts); 129extern int nr_processes(void); 130extern unsigned long nr_running(void); 131extern unsigned long nr_uninterruptible(void); 132extern unsigned long nr_active(void); 133extern unsigned long nr_iowait(void); 134extern unsigned long weighted_cpuload(const int cpu); 135 136struct seq_file; 137struct cfs_rq; 138#ifdef CONFIG_SCHED_DEBUG 139extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 140extern void proc_sched_set_task(struct task_struct *p); 141extern void 142print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 143#else 144static inline void 145proc_sched_show_task(struct task_struct *p, struct seq_file *m) 146{ 147} 148static inline void proc_sched_set_task(struct task_struct *p) 149{ 150} 151static inline void 152print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) 153{ 154} 155#endif 156 157/* 158 * Task state bitmask. NOTE! These bits are also 159 * encoded in fs/proc/array.c: get_task_state(). 160 * 161 * We have two separate sets of flags: task->state 162 * is about runnability, while task->exit_state are 163 * about the task exiting. Confusing, but this way 164 * modifying one set can't modify the other one by 165 * mistake. 166 */ 167#define TASK_RUNNING 0 168#define TASK_INTERRUPTIBLE 1 169#define TASK_UNINTERRUPTIBLE 2 170#define TASK_STOPPED 4 171#define TASK_TRACED 8 172/* in tsk->exit_state */ 173#define EXIT_ZOMBIE 16 174#define EXIT_DEAD 32 175/* in tsk->state again */ 176#define TASK_NONINTERACTIVE 64 177#define TASK_DEAD 128 178 179#define __set_task_state(tsk, state_value) \ 180 do { (tsk)->state = (state_value); } while (0) 181#define set_task_state(tsk, state_value) \ 182 set_mb((tsk)->state, (state_value)) 183 184/* 185 * set_current_state() includes a barrier so that the write of current->state 186 * is correctly serialised wrt the caller's subsequent test of whether to 187 * actually sleep: 188 * 189 * set_current_state(TASK_UNINTERRUPTIBLE); 190 * if (do_i_need_to_sleep()) 191 * schedule(); 192 * 193 * If the caller does not need such serialisation then use __set_current_state() 194 */ 195#define __set_current_state(state_value) \ 196 do { current->state = (state_value); } while (0) 197#define set_current_state(state_value) \ 198 set_mb(current->state, (state_value)) 199 200/* Task command name length */ 201#define TASK_COMM_LEN 16 202 203#include <linux/spinlock.h> 204 205/* 206 * This serializes "schedule()" and also protects 207 * the run-queue from deletions/modifications (but 208 * _adding_ to the beginning of the run-queue has 209 * a separate lock). 210 */ 211extern rwlock_t tasklist_lock; 212extern spinlock_t mmlist_lock; 213 214struct task_struct; 215 216extern void sched_init(void); 217extern void sched_init_smp(void); 218extern void init_idle(struct task_struct *idle, int cpu); 219extern void init_idle_bootup_task(struct task_struct *idle); 220 221extern cpumask_t nohz_cpu_mask; 222#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ) 223extern int select_nohz_load_balancer(int cpu); 224#else 225static inline int select_nohz_load_balancer(int cpu) 226{ 227 return 0; 228} 229#endif 230 231/* 232 * Only dump TASK_* tasks. (0 for all tasks) 233 */ 234extern void show_state_filter(unsigned long state_filter); 235 236static inline void show_state(void) 237{ 238 show_state_filter(0); 239} 240 241extern void show_regs(struct pt_regs *); 242 243/* 244 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 245 * task), SP is the stack pointer of the first frame that should be shown in the back 246 * trace (or NULL if the entire call-chain of the task should be shown). 247 */ 248extern void show_stack(struct task_struct *task, unsigned long *sp); 249 250void io_schedule(void); 251long io_schedule_timeout(long timeout); 252 253extern void cpu_init (void); 254extern void trap_init(void); 255extern void update_process_times(int user); 256extern void scheduler_tick(void); 257 258#ifdef CONFIG_DETECT_SOFTLOCKUP 259extern void softlockup_tick(void); 260extern void spawn_softlockup_task(void); 261extern void touch_softlockup_watchdog(void); 262extern void touch_all_softlockup_watchdogs(void); 263#else 264static inline void softlockup_tick(void) 265{ 266} 267static inline void spawn_softlockup_task(void) 268{ 269} 270static inline void touch_softlockup_watchdog(void) 271{ 272} 273static inline void touch_all_softlockup_watchdogs(void) 274{ 275} 276#endif 277 278 279/* Attach to any functions which should be ignored in wchan output. */ 280#define __sched __attribute__((__section__(".sched.text"))) 281/* Is this address in the __sched functions? */ 282extern int in_sched_functions(unsigned long addr); 283 284#define MAX_SCHEDULE_TIMEOUT LONG_MAX 285extern signed long FASTCALL(schedule_timeout(signed long timeout)); 286extern signed long schedule_timeout_interruptible(signed long timeout); 287extern signed long schedule_timeout_uninterruptible(signed long timeout); 288asmlinkage void schedule(void); 289 290struct nsproxy; 291struct user_namespace; 292 293/* Maximum number of active map areas.. This is a random (large) number */ 294#define DEFAULT_MAX_MAP_COUNT 65536 295 296extern int sysctl_max_map_count; 297 298#include <linux/aio.h> 299 300extern unsigned long 301arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 302 unsigned long, unsigned long); 303extern unsigned long 304arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 305 unsigned long len, unsigned long pgoff, 306 unsigned long flags); 307extern void arch_unmap_area(struct mm_struct *, unsigned long); 308extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); 309 310#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS 311/* 312 * The mm counters are not protected by its page_table_lock, 313 * so must be incremented atomically. 314 */ 315#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value) 316#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member)) 317#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member) 318#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member) 319#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member) 320typedef atomic_long_t mm_counter_t; 321 322#else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */ 323/* 324 * The mm counters are protected by its page_table_lock, 325 * so can be incremented directly. 326 */ 327#define set_mm_counter(mm, member, value) (mm)->_##member = (value) 328#define get_mm_counter(mm, member) ((mm)->_##member) 329#define add_mm_counter(mm, member, value) (mm)->_##member += (value) 330#define inc_mm_counter(mm, member) (mm)->_##member++ 331#define dec_mm_counter(mm, member) (mm)->_##member-- 332typedef unsigned long mm_counter_t; 333 334#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */ 335 336#define get_mm_rss(mm) \ 337 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss)) 338#define update_hiwater_rss(mm) do { \ 339 unsigned long _rss = get_mm_rss(mm); \ 340 if ((mm)->hiwater_rss < _rss) \ 341 (mm)->hiwater_rss = _rss; \ 342} while (0) 343#define update_hiwater_vm(mm) do { \ 344 if ((mm)->hiwater_vm < (mm)->total_vm) \ 345 (mm)->hiwater_vm = (mm)->total_vm; \ 346} while (0) 347 348extern void set_dumpable(struct mm_struct *mm, int value); 349extern int get_dumpable(struct mm_struct *mm); 350 351/* mm flags */ 352/* dumpable bits */ 353#define MMF_DUMPABLE 0 /* core dump is permitted */ 354#define MMF_DUMP_SECURELY 1 /* core file is readable only by root */ 355#define MMF_DUMPABLE_BITS 2 356 357/* coredump filter bits */ 358#define MMF_DUMP_ANON_PRIVATE 2 359#define MMF_DUMP_ANON_SHARED 3 360#define MMF_DUMP_MAPPED_PRIVATE 4 361#define MMF_DUMP_MAPPED_SHARED 5 362#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 363#define MMF_DUMP_FILTER_BITS 4 364#define MMF_DUMP_FILTER_MASK \ 365 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 366#define MMF_DUMP_FILTER_DEFAULT \ 367 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED)) 368 369struct mm_struct { 370 struct vm_area_struct * mmap; /* list of VMAs */ 371 struct rb_root mm_rb; 372 struct vm_area_struct * mmap_cache; /* last find_vma result */ 373 unsigned long (*get_unmapped_area) (struct file *filp, 374 unsigned long addr, unsigned long len, 375 unsigned long pgoff, unsigned long flags); 376 void (*unmap_area) (struct mm_struct *mm, unsigned long addr); 377 unsigned long mmap_base; /* base of mmap area */ 378 unsigned long task_size; /* size of task vm space */ 379 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */ 380 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */ 381 pgd_t * pgd; 382 atomic_t mm_users; /* How many users with user space? */ 383 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */ 384 int map_count; /* number of VMAs */ 385 struct rw_semaphore mmap_sem; 386 spinlock_t page_table_lock; /* Protects page tables and some counters */ 387 388 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung 389 * together off init_mm.mmlist, and are protected 390 * by mmlist_lock 391 */ 392 393 /* Special counters, in some configurations protected by the 394 * page_table_lock, in other configurations by being atomic. 395 */ 396 mm_counter_t _file_rss; 397 mm_counter_t _anon_rss; 398 399 unsigned long hiwater_rss; /* High-watermark of RSS usage */ 400 unsigned long hiwater_vm; /* High-water virtual memory usage */ 401 402 unsigned long total_vm, locked_vm, shared_vm, exec_vm; 403 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes; 404 unsigned long start_code, end_code, start_data, end_data; 405 unsigned long start_brk, brk, start_stack; 406 unsigned long arg_start, arg_end, env_start, env_end; 407 408 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */ 409 410 cpumask_t cpu_vm_mask; 411 412 /* Architecture-specific MM context */ 413 mm_context_t context; 414 415 /* Swap token stuff */ 416 /* 417 * Last value of global fault stamp as seen by this process. 418 * In other words, this value gives an indication of how long 419 * it has been since this task got the token. 420 * Look at mm/thrash.c 421 */ 422 unsigned int faultstamp; 423 unsigned int token_priority; 424 unsigned int last_interval; 425 426 unsigned long flags; /* Must use atomic bitops to access the bits */ 427 428 /* coredumping support */ 429 int core_waiters; 430 struct completion *core_startup_done, core_done; 431 432 /* aio bits */ 433 rwlock_t ioctx_list_lock; 434 struct kioctx *ioctx_list; 435}; 436 437struct sighand_struct { 438 atomic_t count; 439 struct k_sigaction action[_NSIG]; 440 spinlock_t siglock; 441 wait_queue_head_t signalfd_wqh; 442}; 443 444struct pacct_struct { 445 int ac_flag; 446 long ac_exitcode; 447 unsigned long ac_mem; 448 cputime_t ac_utime, ac_stime; 449 unsigned long ac_minflt, ac_majflt; 450}; 451 452/* 453 * NOTE! "signal_struct" does not have it's own 454 * locking, because a shared signal_struct always 455 * implies a shared sighand_struct, so locking 456 * sighand_struct is always a proper superset of 457 * the locking of signal_struct. 458 */ 459struct signal_struct { 460 atomic_t count; 461 atomic_t live; 462 463 wait_queue_head_t wait_chldexit; /* for wait4() */ 464 465 /* current thread group signal load-balancing target: */ 466 struct task_struct *curr_target; 467 468 /* shared signal handling: */ 469 struct sigpending shared_pending; 470 471 /* thread group exit support */ 472 int group_exit_code; 473 /* overloaded: 474 * - notify group_exit_task when ->count is equal to notify_count 475 * - everyone except group_exit_task is stopped during signal delivery 476 * of fatal signals, group_exit_task processes the signal. 477 */ 478 struct task_struct *group_exit_task; 479 int notify_count; 480 481 /* thread group stop support, overloads group_exit_code too */ 482 int group_stop_count; 483 unsigned int flags; /* see SIGNAL_* flags below */ 484 485 /* POSIX.1b Interval Timers */ 486 struct list_head posix_timers; 487 488 /* ITIMER_REAL timer for the process */ 489 struct hrtimer real_timer; 490 struct task_struct *tsk; 491 ktime_t it_real_incr; 492 493 /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */ 494 cputime_t it_prof_expires, it_virt_expires; 495 cputime_t it_prof_incr, it_virt_incr; 496 497 /* job control IDs */ 498 pid_t pgrp; 499 struct pid *tty_old_pgrp; 500 501 union { 502 pid_t session __deprecated; 503 pid_t __session; 504 }; 505 506 /* boolean value for session group leader */ 507 int leader; 508 509 struct tty_struct *tty; /* NULL if no tty */ 510 511 /* 512 * Cumulative resource counters for dead threads in the group, 513 * and for reaped dead child processes forked by this group. 514 * Live threads maintain their own counters and add to these 515 * in __exit_signal, except for the group leader. 516 */ 517 cputime_t utime, stime, cutime, cstime; 518 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 519 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 520 unsigned long inblock, oublock, cinblock, coublock; 521 522 /* 523 * Cumulative ns of scheduled CPU time for dead threads in the 524 * group, not including a zombie group leader. (This only differs 525 * from jiffies_to_ns(utime + stime) if sched_clock uses something 526 * other than jiffies.) 527 */ 528 unsigned long long sum_sched_runtime; 529 530 /* 531 * We don't bother to synchronize most readers of this at all, 532 * because there is no reader checking a limit that actually needs 533 * to get both rlim_cur and rlim_max atomically, and either one 534 * alone is a single word that can safely be read normally. 535 * getrlimit/setrlimit use task_lock(current->group_leader) to 536 * protect this instead of the siglock, because they really 537 * have no need to disable irqs. 538 */ 539 struct rlimit rlim[RLIM_NLIMITS]; 540 541 struct list_head cpu_timers[3]; 542 543 /* keep the process-shared keyrings here so that they do the right 544 * thing in threads created with CLONE_THREAD */ 545#ifdef CONFIG_KEYS 546 struct key *session_keyring; /* keyring inherited over fork */ 547 struct key *process_keyring; /* keyring private to this process */ 548#endif 549#ifdef CONFIG_BSD_PROCESS_ACCT 550 struct pacct_struct pacct; /* per-process accounting information */ 551#endif 552#ifdef CONFIG_TASKSTATS 553 struct taskstats *stats; 554#endif 555#ifdef CONFIG_AUDIT 556 unsigned audit_tty; 557 struct tty_audit_buf *tty_audit_buf; 558#endif 559}; 560 561/* Context switch must be unlocked if interrupts are to be enabled */ 562#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW 563# define __ARCH_WANT_UNLOCKED_CTXSW 564#endif 565 566/* 567 * Bits in flags field of signal_struct. 568 */ 569#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 570#define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */ 571#define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */ 572#define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */ 573 574/* 575 * Some day this will be a full-fledged user tracking system.. 576 */ 577struct user_struct { 578 atomic_t __count; /* reference count */ 579 atomic_t processes; /* How many processes does this user have? */ 580 atomic_t files; /* How many open files does this user have? */ 581 atomic_t sigpending; /* How many pending signals does this user have? */ 582#ifdef CONFIG_INOTIFY_USER 583 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 584 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 585#endif 586 /* protected by mq_lock */ 587 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 588 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 589 590#ifdef CONFIG_KEYS 591 struct key *uid_keyring; /* UID specific keyring */ 592 struct key *session_keyring; /* UID's default session keyring */ 593#endif 594 595 /* Hash table maintenance information */ 596 struct hlist_node uidhash_node; 597 uid_t uid; 598}; 599 600extern struct user_struct *find_user(uid_t); 601 602extern struct user_struct root_user; 603#define INIT_USER (&root_user) 604 605struct backing_dev_info; 606struct reclaim_state; 607 608#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 609struct sched_info { 610 /* cumulative counters */ 611 unsigned long pcnt; /* # of times run on this cpu */ 612 unsigned long long cpu_time, /* time spent on the cpu */ 613 run_delay; /* time spent waiting on a runqueue */ 614 615 /* timestamps */ 616 unsigned long long last_arrival,/* when we last ran on a cpu */ 617 last_queued; /* when we were last queued to run */ 618}; 619#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ 620 621#ifdef CONFIG_SCHEDSTATS 622extern const struct file_operations proc_schedstat_operations; 623#endif /* CONFIG_SCHEDSTATS */ 624 625#ifdef CONFIG_TASK_DELAY_ACCT 626struct task_delay_info { 627 spinlock_t lock; 628 unsigned int flags; /* Private per-task flags */ 629 630 /* For each stat XXX, add following, aligned appropriately 631 * 632 * struct timespec XXX_start, XXX_end; 633 * u64 XXX_delay; 634 * u32 XXX_count; 635 * 636 * Atomicity of updates to XXX_delay, XXX_count protected by 637 * single lock above (split into XXX_lock if contention is an issue). 638 */ 639 640 /* 641 * XXX_count is incremented on every XXX operation, the delay 642 * associated with the operation is added to XXX_delay. 643 * XXX_delay contains the accumulated delay time in nanoseconds. 644 */ 645 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ 646 u64 blkio_delay; /* wait for sync block io completion */ 647 u64 swapin_delay; /* wait for swapin block io completion */ 648 u32 blkio_count; /* total count of the number of sync block */ 649 /* io operations performed */ 650 u32 swapin_count; /* total count of the number of swapin block */ 651 /* io operations performed */ 652}; 653#endif /* CONFIG_TASK_DELAY_ACCT */ 654 655static inline int sched_info_on(void) 656{ 657#ifdef CONFIG_SCHEDSTATS 658 return 1; 659#elif defined(CONFIG_TASK_DELAY_ACCT) 660 extern int delayacct_on; 661 return delayacct_on; 662#else 663 return 0; 664#endif 665} 666 667enum cpu_idle_type { 668 CPU_IDLE, 669 CPU_NOT_IDLE, 670 CPU_NEWLY_IDLE, 671 CPU_MAX_IDLE_TYPES 672}; 673 674/* 675 * sched-domains (multiprocessor balancing) declarations: 676 */ 677 678/* 679 * Increase resolution of nice-level calculations: 680 */ 681#define SCHED_LOAD_SHIFT 10 682#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT) 683 684#define SCHED_LOAD_SCALE_FUZZ SCHED_LOAD_SCALE 685 686#ifdef CONFIG_SMP 687#define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */ 688#define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */ 689#define SD_BALANCE_EXEC 4 /* Balance on exec */ 690#define SD_BALANCE_FORK 8 /* Balance on fork, clone */ 691#define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */ 692#define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */ 693#define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */ 694#define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */ 695#define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */ 696#define SD_SHARE_PKG_RESOURCES 512 /* Domain members share cpu pkg resources */ 697#define SD_SERIALIZE 1024 /* Only a single load balancing instance */ 698 699#define BALANCE_FOR_MC_POWER \ 700 (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0) 701 702#define BALANCE_FOR_PKG_POWER \ 703 ((sched_mc_power_savings || sched_smt_power_savings) ? \ 704 SD_POWERSAVINGS_BALANCE : 0) 705 706#define test_sd_parent(sd, flag) ((sd->parent && \ 707 (sd->parent->flags & flag)) ? 1 : 0) 708 709 710struct sched_group { 711 struct sched_group *next; /* Must be a circular list */ 712 cpumask_t cpumask; 713 714 /* 715 * CPU power of this group, SCHED_LOAD_SCALE being max power for a 716 * single CPU. This is read only (except for setup, hotplug CPU). 717 * Note : Never change cpu_power without recompute its reciprocal 718 */ 719 unsigned int __cpu_power; 720 /* 721 * reciprocal value of cpu_power to avoid expensive divides 722 * (see include/linux/reciprocal_div.h) 723 */ 724 u32 reciprocal_cpu_power; 725}; 726 727struct sched_domain { 728 /* These fields must be setup */ 729 struct sched_domain *parent; /* top domain must be null terminated */ 730 struct sched_domain *child; /* bottom domain must be null terminated */ 731 struct sched_group *groups; /* the balancing groups of the domain */ 732 cpumask_t span; /* span of all CPUs in this domain */ 733 unsigned long min_interval; /* Minimum balance interval ms */ 734 unsigned long max_interval; /* Maximum balance interval ms */ 735 unsigned int busy_factor; /* less balancing by factor if busy */ 736 unsigned int imbalance_pct; /* No balance until over watermark */ 737 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 738 unsigned int busy_idx; 739 unsigned int idle_idx; 740 unsigned int newidle_idx; 741 unsigned int wake_idx; 742 unsigned int forkexec_idx; 743 int flags; /* See SD_* */ 744 745 /* Runtime fields. */ 746 unsigned long last_balance; /* init to jiffies. units in jiffies */ 747 unsigned int balance_interval; /* initialise to 1. units in ms. */ 748 unsigned int nr_balance_failed; /* initialise to 0 */ 749 750#ifdef CONFIG_SCHEDSTATS 751 /* load_balance() stats */ 752 unsigned long lb_cnt[CPU_MAX_IDLE_TYPES]; 753 unsigned long lb_failed[CPU_MAX_IDLE_TYPES]; 754 unsigned long lb_balanced[CPU_MAX_IDLE_TYPES]; 755 unsigned long lb_imbalance[CPU_MAX_IDLE_TYPES]; 756 unsigned long lb_gained[CPU_MAX_IDLE_TYPES]; 757 unsigned long lb_hot_gained[CPU_MAX_IDLE_TYPES]; 758 unsigned long lb_nobusyg[CPU_MAX_IDLE_TYPES]; 759 unsigned long lb_nobusyq[CPU_MAX_IDLE_TYPES]; 760 761 /* Active load balancing */ 762 unsigned long alb_cnt; 763 unsigned long alb_failed; 764 unsigned long alb_pushed; 765 766 /* SD_BALANCE_EXEC stats */ 767 unsigned long sbe_cnt; 768 unsigned long sbe_balanced; 769 unsigned long sbe_pushed; 770 771 /* SD_BALANCE_FORK stats */ 772 unsigned long sbf_cnt; 773 unsigned long sbf_balanced; 774 unsigned long sbf_pushed; 775 776 /* try_to_wake_up() stats */ 777 unsigned long ttwu_wake_remote; 778 unsigned long ttwu_move_affine; 779 unsigned long ttwu_move_balance; 780#endif 781}; 782 783extern int partition_sched_domains(cpumask_t *partition1, 784 cpumask_t *partition2); 785 786#endif /* CONFIG_SMP */ 787 788/* 789 * A runqueue laden with a single nice 0 task scores a weighted_cpuload of 790 * SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a 791 * task of nice 0 or enough lower priority tasks to bring up the 792 * weighted_cpuload 793 */ 794static inline int above_background_load(void) 795{ 796 unsigned long cpu; 797 798 for_each_online_cpu(cpu) { 799 if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE) 800 return 1; 801 } 802 return 0; 803} 804 805struct io_context; /* See blkdev.h */ 806struct cpuset; 807 808#define NGROUPS_SMALL 32 809#define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t))) 810struct group_info { 811 int ngroups; 812 atomic_t usage; 813 gid_t small_block[NGROUPS_SMALL]; 814 int nblocks; 815 gid_t *blocks[0]; 816}; 817 818/* 819 * get_group_info() must be called with the owning task locked (via task_lock()) 820 * when task != current. The reason being that the vast majority of callers are 821 * looking at current->group_info, which can not be changed except by the 822 * current task. Changing current->group_info requires the task lock, too. 823 */ 824#define get_group_info(group_info) do { \ 825 atomic_inc(&(group_info)->usage); \ 826} while (0) 827 828#define put_group_info(group_info) do { \ 829 if (atomic_dec_and_test(&(group_info)->usage)) \ 830 groups_free(group_info); \ 831} while (0) 832 833extern struct group_info *groups_alloc(int gidsetsize); 834extern void groups_free(struct group_info *group_info); 835extern int set_current_groups(struct group_info *group_info); 836extern int groups_search(struct group_info *group_info, gid_t grp); 837/* access the groups "array" with this macro */ 838#define GROUP_AT(gi, i) \ 839 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK]) 840 841#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 842extern void prefetch_stack(struct task_struct *t); 843#else 844static inline void prefetch_stack(struct task_struct *t) { } 845#endif 846 847struct audit_context; /* See audit.c */ 848struct mempolicy; 849struct pipe_inode_info; 850struct uts_namespace; 851 852struct rq; 853struct sched_domain; 854 855struct sched_class { 856 struct sched_class *next; 857 858 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup); 859 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep); 860 void (*yield_task) (struct rq *rq, struct task_struct *p); 861 862 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p); 863 864 struct task_struct * (*pick_next_task) (struct rq *rq); 865 void (*put_prev_task) (struct rq *rq, struct task_struct *p); 866 867 unsigned long (*load_balance) (struct rq *this_rq, int this_cpu, 868 struct rq *busiest, 869 unsigned long max_nr_move, unsigned long max_load_move, 870 struct sched_domain *sd, enum cpu_idle_type idle, 871 int *all_pinned, int *this_best_prio); 872 873 void (*set_curr_task) (struct rq *rq); 874 void (*task_tick) (struct rq *rq, struct task_struct *p); 875 void (*task_new) (struct rq *rq, struct task_struct *p); 876}; 877 878struct load_weight { 879 unsigned long weight, inv_weight; 880}; 881 882/* 883 * CFS stats for a schedulable entity (task, task-group etc) 884 * 885 * Current field usage histogram: 886 * 887 * 4 se->block_start 888 * 4 se->run_node 889 * 4 se->sleep_start 890 * 4 se->sleep_start_fair 891 * 6 se->load.weight 892 * 7 se->delta_fair 893 * 15 se->wait_runtime 894 */ 895struct sched_entity { 896 long wait_runtime; 897 unsigned long delta_fair_run; 898 unsigned long delta_fair_sleep; 899 unsigned long delta_exec; 900 s64 fair_key; 901 struct load_weight load; /* for load-balancing */ 902 struct rb_node run_node; 903 unsigned int on_rq; 904 905 u64 exec_start; 906 u64 sum_exec_runtime; 907 u64 prev_sum_exec_runtime; 908 u64 wait_start_fair; 909 u64 sleep_start_fair; 910 911#ifdef CONFIG_SCHEDSTATS 912 u64 wait_start; 913 u64 wait_max; 914 s64 sum_wait_runtime; 915 916 u64 sleep_start; 917 u64 sleep_max; 918 s64 sum_sleep_runtime; 919 920 u64 block_start; 921 u64 block_max; 922 u64 exec_max; 923 924 unsigned long wait_runtime_overruns; 925 unsigned long wait_runtime_underruns; 926#endif 927 928#ifdef CONFIG_FAIR_GROUP_SCHED 929 struct sched_entity *parent; 930 /* rq on which this entity is (to be) queued: */ 931 struct cfs_rq *cfs_rq; 932 /* rq "owned" by this entity/group: */ 933 struct cfs_rq *my_q; 934#endif 935}; 936 937struct task_struct { 938 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 939 void *stack; 940 atomic_t usage; 941 unsigned int flags; /* per process flags, defined below */ 942 unsigned int ptrace; 943 944 int lock_depth; /* BKL lock depth */ 945 946#ifdef CONFIG_SMP 947#ifdef __ARCH_WANT_UNLOCKED_CTXSW 948 int oncpu; 949#endif 950#endif 951 952 int prio, static_prio, normal_prio; 953 struct list_head run_list; 954 struct sched_class *sched_class; 955 struct sched_entity se; 956 957#ifdef CONFIG_PREEMPT_NOTIFIERS 958 /* list of struct preempt_notifier: */ 959 struct hlist_head preempt_notifiers; 960#endif 961 962 unsigned short ioprio; 963#ifdef CONFIG_BLK_DEV_IO_TRACE 964 unsigned int btrace_seq; 965#endif 966 967 unsigned int policy; 968 cpumask_t cpus_allowed; 969 unsigned int time_slice; 970 971#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 972 struct sched_info sched_info; 973#endif 974 975 struct list_head tasks; 976 /* 977 * ptrace_list/ptrace_children forms the list of my children 978 * that were stolen by a ptracer. 979 */ 980 struct list_head ptrace_children; 981 struct list_head ptrace_list; 982 983 struct mm_struct *mm, *active_mm; 984 985/* task state */ 986 struct linux_binfmt *binfmt; 987 int exit_state; 988 int exit_code, exit_signal; 989 int pdeath_signal; /* The signal sent when the parent dies */ 990 /* ??? */ 991 unsigned int personality; 992 unsigned did_exec:1; 993 pid_t pid; 994 pid_t tgid; 995 996#ifdef CONFIG_CC_STACKPROTECTOR 997 /* Canary value for the -fstack-protector gcc feature */ 998 unsigned long stack_canary; 999#endif 1000 /* 1001 * pointers to (original) parent process, youngest child, younger sibling, 1002 * older sibling, respectively. (p->father can be replaced with 1003 * p->parent->pid) 1004 */ 1005 struct task_struct *real_parent; /* real parent process (when being debugged) */ 1006 struct task_struct *parent; /* parent process */ 1007 /* 1008 * children/sibling forms the list of my children plus the 1009 * tasks I'm ptracing. 1010 */ 1011 struct list_head children; /* list of my children */ 1012 struct list_head sibling; /* linkage in my parent's children list */ 1013 struct task_struct *group_leader; /* threadgroup leader */ 1014 1015 /* PID/PID hash table linkage. */ 1016 struct pid_link pids[PIDTYPE_MAX]; 1017 struct list_head thread_group; 1018 1019 struct completion *vfork_done; /* for vfork() */ 1020 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1021 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1022 1023 unsigned int rt_priority; 1024 cputime_t utime, stime; 1025 unsigned long nvcsw, nivcsw; /* context switch counts */ 1026 struct timespec start_time; /* monotonic time */ 1027 struct timespec real_start_time; /* boot based time */ 1028/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1029 unsigned long min_flt, maj_flt; 1030 1031 cputime_t it_prof_expires, it_virt_expires; 1032 unsigned long long it_sched_expires; 1033 struct list_head cpu_timers[3]; 1034 1035/* process credentials */ 1036 uid_t uid,euid,suid,fsuid; 1037 gid_t gid,egid,sgid,fsgid; 1038 struct group_info *group_info; 1039 kernel_cap_t cap_effective, cap_inheritable, cap_permitted; 1040 unsigned keep_capabilities:1; 1041 struct user_struct *user; 1042#ifdef CONFIG_KEYS 1043 struct key *request_key_auth; /* assumed request_key authority */ 1044 struct key *thread_keyring; /* keyring private to this thread */ 1045 unsigned char jit_keyring; /* default keyring to attach requested keys to */ 1046#endif 1047 /* 1048 * fpu_counter contains the number of consecutive context switches 1049 * that the FPU is used. If this is over a threshold, the lazy fpu 1050 * saving becomes unlazy to save the trap. This is an unsigned char 1051 * so that after 256 times the counter wraps and the behavior turns 1052 * lazy again; this to deal with bursty apps that only use FPU for 1053 * a short time 1054 */ 1055 unsigned char fpu_counter; 1056 int oomkilladj; /* OOM kill score adjustment (bit shift). */ 1057 char comm[TASK_COMM_LEN]; /* executable name excluding path 1058 - access with [gs]et_task_comm (which lock 1059 it with task_lock()) 1060 - initialized normally by flush_old_exec */ 1061/* file system info */ 1062 int link_count, total_link_count; 1063#ifdef CONFIG_SYSVIPC 1064/* ipc stuff */ 1065 struct sysv_sem sysvsem; 1066#endif 1067/* CPU-specific state of this task */ 1068 struct thread_struct thread; 1069/* filesystem information */ 1070 struct fs_struct *fs; 1071/* open file information */ 1072 struct files_struct *files; 1073/* namespaces */ 1074 struct nsproxy *nsproxy; 1075/* signal handlers */ 1076 struct signal_struct *signal; 1077 struct sighand_struct *sighand; 1078 1079 sigset_t blocked, real_blocked; 1080 sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */ 1081 struct sigpending pending; 1082 1083 unsigned long sas_ss_sp; 1084 size_t sas_ss_size; 1085 int (*notifier)(void *priv); 1086 void *notifier_data; 1087 sigset_t *notifier_mask; 1088 1089 void *security; 1090 struct audit_context *audit_context; 1091 seccomp_t seccomp; 1092 1093/* Thread group tracking */ 1094 u32 parent_exec_id; 1095 u32 self_exec_id; 1096/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */ 1097 spinlock_t alloc_lock; 1098 1099 /* Protection of the PI data structures: */ 1100 spinlock_t pi_lock; 1101 1102#ifdef CONFIG_RT_MUTEXES 1103 /* PI waiters blocked on a rt_mutex held by this task */ 1104 struct plist_head pi_waiters; 1105 /* Deadlock detection and priority inheritance handling */ 1106 struct rt_mutex_waiter *pi_blocked_on; 1107#endif 1108 1109#ifdef CONFIG_DEBUG_MUTEXES 1110 /* mutex deadlock detection */ 1111 struct mutex_waiter *blocked_on; 1112#endif 1113#ifdef CONFIG_TRACE_IRQFLAGS 1114 unsigned int irq_events; 1115 int hardirqs_enabled; 1116 unsigned long hardirq_enable_ip; 1117 unsigned int hardirq_enable_event; 1118 unsigned long hardirq_disable_ip; 1119 unsigned int hardirq_disable_event; 1120 int softirqs_enabled; 1121 unsigned long softirq_disable_ip; 1122 unsigned int softirq_disable_event; 1123 unsigned long softirq_enable_ip; 1124 unsigned int softirq_enable_event; 1125 int hardirq_context; 1126 int softirq_context; 1127#endif 1128#ifdef CONFIG_LOCKDEP 1129# define MAX_LOCK_DEPTH 30UL 1130 u64 curr_chain_key; 1131 int lockdep_depth; 1132 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1133 unsigned int lockdep_recursion; 1134#endif 1135 1136/* journalling filesystem info */ 1137 void *journal_info; 1138 1139/* stacked block device info */ 1140 struct bio *bio_list, **bio_tail; 1141 1142/* VM state */ 1143 struct reclaim_state *reclaim_state; 1144 1145 struct backing_dev_info *backing_dev_info; 1146 1147 struct io_context *io_context; 1148 1149 unsigned long ptrace_message; 1150 siginfo_t *last_siginfo; /* For ptrace use. */ 1151/* 1152 * current io wait handle: wait queue entry to use for io waits 1153 * If this thread is processing aio, this points at the waitqueue 1154 * inside the currently handled kiocb. It may be NULL (i.e. default 1155 * to a stack based synchronous wait) if its doing sync IO. 1156 */ 1157 wait_queue_t *io_wait; 1158#ifdef CONFIG_TASK_XACCT 1159/* i/o counters(bytes read/written, #syscalls */ 1160 u64 rchar, wchar, syscr, syscw; 1161#endif 1162 struct task_io_accounting ioac; 1163#if defined(CONFIG_TASK_XACCT) 1164 u64 acct_rss_mem1; /* accumulated rss usage */ 1165 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1166 cputime_t acct_stimexpd;/* stime since last update */ 1167#endif 1168#ifdef CONFIG_NUMA 1169 struct mempolicy *mempolicy; 1170 short il_next; 1171#endif 1172#ifdef CONFIG_CPUSETS 1173 struct cpuset *cpuset; 1174 nodemask_t mems_allowed; 1175 int cpuset_mems_generation; 1176 int cpuset_mem_spread_rotor; 1177#endif 1178 struct robust_list_head __user *robust_list; 1179#ifdef CONFIG_COMPAT 1180 struct compat_robust_list_head __user *compat_robust_list; 1181#endif 1182 struct list_head pi_state_list; 1183 struct futex_pi_state *pi_state_cache; 1184 1185 atomic_t fs_excl; /* holding fs exclusive resources */ 1186 struct rcu_head rcu; 1187 1188 /* 1189 * cache last used pipe for splice 1190 */ 1191 struct pipe_inode_info *splice_pipe; 1192#ifdef CONFIG_TASK_DELAY_ACCT 1193 struct task_delay_info *delays; 1194#endif 1195#ifdef CONFIG_FAULT_INJECTION 1196 int make_it_fail; 1197#endif 1198}; 1199 1200/* 1201 * Priority of a process goes from 0..MAX_PRIO-1, valid RT 1202 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH 1203 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority 1204 * values are inverted: lower p->prio value means higher priority. 1205 * 1206 * The MAX_USER_RT_PRIO value allows the actual maximum 1207 * RT priority to be separate from the value exported to 1208 * user-space. This allows kernel threads to set their 1209 * priority to a value higher than any user task. Note: 1210 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO. 1211 */ 1212 1213#define MAX_USER_RT_PRIO 100 1214#define MAX_RT_PRIO MAX_USER_RT_PRIO 1215 1216#define MAX_PRIO (MAX_RT_PRIO + 40) 1217#define DEFAULT_PRIO (MAX_RT_PRIO + 20) 1218 1219static inline int rt_prio(int prio) 1220{ 1221 if (unlikely(prio < MAX_RT_PRIO)) 1222 return 1; 1223 return 0; 1224} 1225 1226static inline int rt_task(struct task_struct *p) 1227{ 1228 return rt_prio(p->prio); 1229} 1230 1231static inline pid_t process_group(struct task_struct *tsk) 1232{ 1233 return tsk->signal->pgrp; 1234} 1235 1236static inline pid_t signal_session(struct signal_struct *sig) 1237{ 1238 return sig->__session; 1239} 1240 1241static inline pid_t process_session(struct task_struct *tsk) 1242{ 1243 return signal_session(tsk->signal); 1244} 1245 1246static inline void set_signal_session(struct signal_struct *sig, pid_t session) 1247{ 1248 sig->__session = session; 1249} 1250 1251static inline struct pid *task_pid(struct task_struct *task) 1252{ 1253 return task->pids[PIDTYPE_PID].pid; 1254} 1255 1256static inline struct pid *task_tgid(struct task_struct *task) 1257{ 1258 return task->group_leader->pids[PIDTYPE_PID].pid; 1259} 1260 1261static inline struct pid *task_pgrp(struct task_struct *task) 1262{ 1263 return task->group_leader->pids[PIDTYPE_PGID].pid; 1264} 1265 1266static inline struct pid *task_session(struct task_struct *task) 1267{ 1268 return task->group_leader->pids[PIDTYPE_SID].pid; 1269} 1270 1271/** 1272 * pid_alive - check that a task structure is not stale 1273 * @p: Task structure to be checked. 1274 * 1275 * Test if a process is not yet dead (at most zombie state) 1276 * If pid_alive fails, then pointers within the task structure 1277 * can be stale and must not be dereferenced. 1278 */ 1279static inline int pid_alive(struct task_struct *p) 1280{ 1281 return p->pids[PIDTYPE_PID].pid != NULL; 1282} 1283 1284/** 1285 * is_init - check if a task structure is init 1286 * @tsk: Task structure to be checked. 1287 * 1288 * Check if a task structure is the first user space task the kernel created. 1289 */ 1290static inline int is_init(struct task_struct *tsk) 1291{ 1292 return tsk->pid == 1; 1293} 1294 1295extern struct pid *cad_pid; 1296 1297extern void free_task(struct task_struct *tsk); 1298#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1299 1300extern void __put_task_struct(struct task_struct *t); 1301 1302static inline void put_task_struct(struct task_struct *t) 1303{ 1304 if (atomic_dec_and_test(&t->usage)) 1305 __put_task_struct(t); 1306} 1307 1308/* 1309 * Per process flags 1310 */ 1311#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */ 1312 /* Not implemented yet, only for 486*/ 1313#define PF_STARTING 0x00000002 /* being created */ 1314#define PF_EXITING 0x00000004 /* getting shut down */ 1315#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1316#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1317#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1318#define PF_DUMPCORE 0x00000200 /* dumped core */ 1319#define PF_SIGNALED 0x00000400 /* killed by a signal */ 1320#define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1321#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */ 1322#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1323#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1324#define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1325#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1326#define PF_KSWAPD 0x00040000 /* I am kswapd */ 1327#define PF_SWAPOFF 0x00080000 /* I am in swapoff */ 1328#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1329#define PF_BORROWED_MM 0x00200000 /* I am a kthread doing use_mm */ 1330#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1331#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1332#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ 1333#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ 1334#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ 1335#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1336#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */ 1337 1338/* 1339 * Only the _current_ task can read/write to tsk->flags, but other 1340 * tasks can access tsk->flags in readonly mode for example 1341 * with tsk_used_math (like during threaded core dumping). 1342 * There is however an exception to this rule during ptrace 1343 * or during fork: the ptracer task is allowed to write to the 1344 * child->flags of its traced child (same goes for fork, the parent 1345 * can write to the child->flags), because we're guaranteed the 1346 * child is not running and in turn not changing child->flags 1347 * at the same time the parent does it. 1348 */ 1349#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1350#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1351#define clear_used_math() clear_stopped_child_used_math(current) 1352#define set_used_math() set_stopped_child_used_math(current) 1353#define conditional_stopped_child_used_math(condition, child) \ 1354 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1355#define conditional_used_math(condition) \ 1356 conditional_stopped_child_used_math(condition, current) 1357#define copy_to_stopped_child_used_math(child) \ 1358 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1359/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1360#define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1361#define used_math() tsk_used_math(current) 1362 1363#ifdef CONFIG_SMP 1364extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask); 1365#else 1366static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 1367{ 1368 if (!cpu_isset(0, new_mask)) 1369 return -EINVAL; 1370 return 0; 1371} 1372#endif 1373 1374extern unsigned long long sched_clock(void); 1375 1376/* 1377 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu 1378 * clock constructed from sched_clock(): 1379 */ 1380extern unsigned long long cpu_clock(int cpu); 1381 1382extern unsigned long long 1383task_sched_runtime(struct task_struct *task); 1384 1385/* sched_exec is called by processes performing an exec */ 1386#ifdef CONFIG_SMP 1387extern void sched_exec(void); 1388#else 1389#define sched_exec() {} 1390#endif 1391 1392extern void sched_clock_idle_sleep_event(void); 1393extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1394 1395#ifdef CONFIG_HOTPLUG_CPU 1396extern void idle_task_exit(void); 1397#else 1398static inline void idle_task_exit(void) {} 1399#endif 1400 1401extern void sched_idle_next(void); 1402 1403extern unsigned int sysctl_sched_latency; 1404extern unsigned int sysctl_sched_min_granularity; 1405extern unsigned int sysctl_sched_wakeup_granularity; 1406extern unsigned int sysctl_sched_batch_wakeup_granularity; 1407extern unsigned int sysctl_sched_stat_granularity; 1408extern unsigned int sysctl_sched_runtime_limit; 1409extern unsigned int sysctl_sched_compat_yield; 1410extern unsigned int sysctl_sched_child_runs_first; 1411extern unsigned int sysctl_sched_features; 1412 1413#ifdef CONFIG_RT_MUTEXES 1414extern int rt_mutex_getprio(struct task_struct *p); 1415extern void rt_mutex_setprio(struct task_struct *p, int prio); 1416extern void rt_mutex_adjust_pi(struct task_struct *p); 1417#else 1418static inline int rt_mutex_getprio(struct task_struct *p) 1419{ 1420 return p->normal_prio; 1421} 1422# define rt_mutex_adjust_pi(p) do { } while (0) 1423#endif 1424 1425extern void set_user_nice(struct task_struct *p, long nice); 1426extern int task_prio(const struct task_struct *p); 1427extern int task_nice(const struct task_struct *p); 1428extern int can_nice(const struct task_struct *p, const int nice); 1429extern int task_curr(const struct task_struct *p); 1430extern int idle_cpu(int cpu); 1431extern int sched_setscheduler(struct task_struct *, int, struct sched_param *); 1432extern struct task_struct *idle_task(int cpu); 1433extern struct task_struct *curr_task(int cpu); 1434extern void set_curr_task(int cpu, struct task_struct *p); 1435 1436void yield(void); 1437 1438/* 1439 * The default (Linux) execution domain. 1440 */ 1441extern struct exec_domain default_exec_domain; 1442 1443union thread_union { 1444 struct thread_info thread_info; 1445 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1446}; 1447 1448#ifndef __HAVE_ARCH_KSTACK_END 1449static inline int kstack_end(void *addr) 1450{ 1451 /* Reliable end of stack detection: 1452 * Some APM bios versions misalign the stack 1453 */ 1454 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 1455} 1456#endif 1457 1458extern union thread_union init_thread_union; 1459extern struct task_struct init_task; 1460 1461extern struct mm_struct init_mm; 1462 1463#define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr) 1464extern struct task_struct *find_task_by_pid_type(int type, int pid); 1465extern void __set_special_pids(pid_t session, pid_t pgrp); 1466 1467/* per-UID process charging. */ 1468extern struct user_struct * alloc_uid(struct user_namespace *, uid_t); 1469static inline struct user_struct *get_uid(struct user_struct *u) 1470{ 1471 atomic_inc(&u->__count); 1472 return u; 1473} 1474extern void free_uid(struct user_struct *); 1475extern void switch_uid(struct user_struct *); 1476extern void release_uids(struct user_namespace *ns); 1477 1478#include <asm/current.h> 1479 1480extern void do_timer(unsigned long ticks); 1481 1482extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state)); 1483extern int FASTCALL(wake_up_process(struct task_struct * tsk)); 1484extern void FASTCALL(wake_up_new_task(struct task_struct * tsk, 1485 unsigned long clone_flags)); 1486#ifdef CONFIG_SMP 1487 extern void kick_process(struct task_struct *tsk); 1488#else 1489 static inline void kick_process(struct task_struct *tsk) { } 1490#endif 1491extern void sched_fork(struct task_struct *p, int clone_flags); 1492extern void sched_dead(struct task_struct *p); 1493 1494extern int in_group_p(gid_t); 1495extern int in_egroup_p(gid_t); 1496 1497extern void proc_caches_init(void); 1498extern void flush_signals(struct task_struct *); 1499extern void ignore_signals(struct task_struct *); 1500extern void flush_signal_handlers(struct task_struct *, int force_default); 1501extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 1502 1503static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 1504{ 1505 unsigned long flags; 1506 int ret; 1507 1508 spin_lock_irqsave(&tsk->sighand->siglock, flags); 1509 ret = dequeue_signal(tsk, mask, info); 1510 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 1511 1512 return ret; 1513} 1514 1515extern void block_all_signals(int (*notifier)(void *priv), void *priv, 1516 sigset_t *mask); 1517extern void unblock_all_signals(void); 1518extern void release_task(struct task_struct * p); 1519extern int send_sig_info(int, struct siginfo *, struct task_struct *); 1520extern int send_group_sig_info(int, struct siginfo *, struct task_struct *); 1521extern int force_sigsegv(int, struct task_struct *); 1522extern int force_sig_info(int, struct siginfo *, struct task_struct *); 1523extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 1524extern int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 1525extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 1526extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32); 1527extern int kill_pgrp(struct pid *pid, int sig, int priv); 1528extern int kill_pid(struct pid *pid, int sig, int priv); 1529extern int kill_proc_info(int, struct siginfo *, pid_t); 1530extern void do_notify_parent(struct task_struct *, int); 1531extern void force_sig(int, struct task_struct *); 1532extern void force_sig_specific(int, struct task_struct *); 1533extern int send_sig(int, struct task_struct *, int); 1534extern void zap_other_threads(struct task_struct *p); 1535extern int kill_proc(pid_t, int, int); 1536extern struct sigqueue *sigqueue_alloc(void); 1537extern void sigqueue_free(struct sigqueue *); 1538extern int send_sigqueue(int, struct sigqueue *, struct task_struct *); 1539extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *); 1540extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 1541extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long); 1542 1543static inline int kill_cad_pid(int sig, int priv) 1544{ 1545 return kill_pid(cad_pid, sig, priv); 1546} 1547 1548/* These can be the second arg to send_sig_info/send_group_sig_info. */ 1549#define SEND_SIG_NOINFO ((struct siginfo *) 0) 1550#define SEND_SIG_PRIV ((struct siginfo *) 1) 1551#define SEND_SIG_FORCED ((struct siginfo *) 2) 1552 1553static inline int is_si_special(const struct siginfo *info) 1554{ 1555 return info <= SEND_SIG_FORCED; 1556} 1557 1558/* True if we are on the alternate signal stack. */ 1559 1560static inline int on_sig_stack(unsigned long sp) 1561{ 1562 return (sp - current->sas_ss_sp < current->sas_ss_size); 1563} 1564 1565static inline int sas_ss_flags(unsigned long sp) 1566{ 1567 return (current->sas_ss_size == 0 ? SS_DISABLE 1568 : on_sig_stack(sp) ? SS_ONSTACK : 0); 1569} 1570 1571/* 1572 * Routines for handling mm_structs 1573 */ 1574extern struct mm_struct * mm_alloc(void); 1575 1576/* mmdrop drops the mm and the page tables */ 1577extern void FASTCALL(__mmdrop(struct mm_struct *)); 1578static inline void mmdrop(struct mm_struct * mm) 1579{ 1580 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 1581 __mmdrop(mm); 1582} 1583 1584/* mmput gets rid of the mappings and all user-space */ 1585extern void mmput(struct mm_struct *); 1586/* Grab a reference to a task's mm, if it is not already going away */ 1587extern struct mm_struct *get_task_mm(struct task_struct *task); 1588/* Remove the current tasks stale references to the old mm_struct */ 1589extern void mm_release(struct task_struct *, struct mm_struct *); 1590 1591extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *); 1592extern void flush_thread(void); 1593extern void exit_thread(void); 1594 1595extern void exit_files(struct task_struct *); 1596extern void __cleanup_signal(struct signal_struct *); 1597extern void __cleanup_sighand(struct sighand_struct *); 1598extern void exit_itimers(struct signal_struct *); 1599 1600extern NORET_TYPE void do_group_exit(int); 1601 1602extern void daemonize(const char *, ...); 1603extern int allow_signal(int); 1604extern int disallow_signal(int); 1605 1606extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *); 1607extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *); 1608struct task_struct *fork_idle(int); 1609 1610extern void set_task_comm(struct task_struct *tsk, char *from); 1611extern void get_task_comm(char *to, struct task_struct *tsk); 1612 1613#ifdef CONFIG_SMP 1614extern void wait_task_inactive(struct task_struct * p); 1615#else 1616#define wait_task_inactive(p) do { } while (0) 1617#endif 1618 1619#define remove_parent(p) list_del_init(&(p)->sibling) 1620#define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children) 1621 1622#define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks) 1623 1624#define for_each_process(p) \ 1625 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 1626 1627/* 1628 * Careful: do_each_thread/while_each_thread is a double loop so 1629 * 'break' will not work as expected - use goto instead. 1630 */ 1631#define do_each_thread(g, t) \ 1632 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 1633 1634#define while_each_thread(g, t) \ 1635 while ((t = next_thread(t)) != g) 1636 1637/* de_thread depends on thread_group_leader not being a pid based check */ 1638#define thread_group_leader(p) (p == p->group_leader) 1639 1640/* Do to the insanities of de_thread it is possible for a process 1641 * to have the pid of the thread group leader without actually being 1642 * the thread group leader. For iteration through the pids in proc 1643 * all we care about is that we have a task with the appropriate 1644 * pid, we don't actually care if we have the right task. 1645 */ 1646static inline int has_group_leader_pid(struct task_struct *p) 1647{ 1648 return p->pid == p->tgid; 1649} 1650 1651static inline struct task_struct *next_thread(const struct task_struct *p) 1652{ 1653 return list_entry(rcu_dereference(p->thread_group.next), 1654 struct task_struct, thread_group); 1655} 1656 1657static inline int thread_group_empty(struct task_struct *p) 1658{ 1659 return list_empty(&p->thread_group); 1660} 1661 1662#define delay_group_leader(p) \ 1663 (thread_group_leader(p) && !thread_group_empty(p)) 1664 1665/* 1666 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 1667 * subscriptions and synchronises with wait4(). Also used in procfs. Also 1668 * pins the final release of task.io_context. Also protects ->cpuset. 1669 * 1670 * Nests both inside and outside of read_lock(&tasklist_lock). 1671 * It must not be nested with write_lock_irq(&tasklist_lock), 1672 * neither inside nor outside. 1673 */ 1674static inline void task_lock(struct task_struct *p) 1675{ 1676 spin_lock(&p->alloc_lock); 1677} 1678 1679static inline void task_unlock(struct task_struct *p) 1680{ 1681 spin_unlock(&p->alloc_lock); 1682} 1683 1684extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 1685 unsigned long *flags); 1686 1687static inline void unlock_task_sighand(struct task_struct *tsk, 1688 unsigned long *flags) 1689{ 1690 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 1691} 1692 1693#ifndef __HAVE_THREAD_FUNCTIONS 1694 1695#define task_thread_info(task) ((struct thread_info *)(task)->stack) 1696#define task_stack_page(task) ((task)->stack) 1697 1698static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 1699{ 1700 *task_thread_info(p) = *task_thread_info(org); 1701 task_thread_info(p)->task = p; 1702} 1703 1704static inline unsigned long *end_of_stack(struct task_struct *p) 1705{ 1706 return (unsigned long *)(task_thread_info(p) + 1); 1707} 1708 1709#endif 1710 1711/* set thread flags in other task's structures 1712 * - see asm/thread_info.h for TIF_xxxx flags available 1713 */ 1714static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 1715{ 1716 set_ti_thread_flag(task_thread_info(tsk), flag); 1717} 1718 1719static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 1720{ 1721 clear_ti_thread_flag(task_thread_info(tsk), flag); 1722} 1723 1724static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 1725{ 1726 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 1727} 1728 1729static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 1730{ 1731 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 1732} 1733 1734static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 1735{ 1736 return test_ti_thread_flag(task_thread_info(tsk), flag); 1737} 1738 1739static inline void set_tsk_need_resched(struct task_struct *tsk) 1740{ 1741 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 1742} 1743 1744static inline void clear_tsk_need_resched(struct task_struct *tsk) 1745{ 1746 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 1747} 1748 1749static inline int signal_pending(struct task_struct *p) 1750{ 1751 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 1752} 1753 1754static inline int need_resched(void) 1755{ 1756 return unlikely(test_thread_flag(TIF_NEED_RESCHED)); 1757} 1758 1759/* 1760 * cond_resched() and cond_resched_lock(): latency reduction via 1761 * explicit rescheduling in places that are safe. The return 1762 * value indicates whether a reschedule was done in fact. 1763 * cond_resched_lock() will drop the spinlock before scheduling, 1764 * cond_resched_softirq() will enable bhs before scheduling. 1765 */ 1766extern int cond_resched(void); 1767extern int cond_resched_lock(spinlock_t * lock); 1768extern int cond_resched_softirq(void); 1769 1770/* 1771 * Does a critical section need to be broken due to another 1772 * task waiting?: 1773 */ 1774#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP) 1775# define need_lockbreak(lock) ((lock)->break_lock) 1776#else 1777# define need_lockbreak(lock) 0 1778#endif 1779 1780/* 1781 * Does a critical section need to be broken due to another 1782 * task waiting or preemption being signalled: 1783 */ 1784static inline int lock_need_resched(spinlock_t *lock) 1785{ 1786 if (need_lockbreak(lock) || need_resched()) 1787 return 1; 1788 return 0; 1789} 1790 1791/* 1792 * Reevaluate whether the task has signals pending delivery. 1793 * Wake the task if so. 1794 * This is required every time the blocked sigset_t changes. 1795 * callers must hold sighand->siglock. 1796 */ 1797extern void recalc_sigpending_and_wake(struct task_struct *t); 1798extern void recalc_sigpending(void); 1799 1800extern void signal_wake_up(struct task_struct *t, int resume_stopped); 1801 1802/* 1803 * Wrappers for p->thread_info->cpu access. No-op on UP. 1804 */ 1805#ifdef CONFIG_SMP 1806 1807static inline unsigned int task_cpu(const struct task_struct *p) 1808{ 1809 return task_thread_info(p)->cpu; 1810} 1811 1812extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 1813 1814#else 1815 1816static inline unsigned int task_cpu(const struct task_struct *p) 1817{ 1818 return 0; 1819} 1820 1821static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 1822{ 1823} 1824 1825#endif /* CONFIG_SMP */ 1826 1827#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 1828extern void arch_pick_mmap_layout(struct mm_struct *mm); 1829#else 1830static inline void arch_pick_mmap_layout(struct mm_struct *mm) 1831{ 1832 mm->mmap_base = TASK_UNMAPPED_BASE; 1833 mm->get_unmapped_area = arch_get_unmapped_area; 1834 mm->unmap_area = arch_unmap_area; 1835} 1836#endif 1837 1838extern long sched_setaffinity(pid_t pid, cpumask_t new_mask); 1839extern long sched_getaffinity(pid_t pid, cpumask_t *mask); 1840 1841extern int sched_mc_power_savings, sched_smt_power_savings; 1842 1843extern void normalize_rt_tasks(void); 1844 1845#ifdef CONFIG_TASK_XACCT 1846static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 1847{ 1848 tsk->rchar += amt; 1849} 1850 1851static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 1852{ 1853 tsk->wchar += amt; 1854} 1855 1856static inline void inc_syscr(struct task_struct *tsk) 1857{ 1858 tsk->syscr++; 1859} 1860 1861static inline void inc_syscw(struct task_struct *tsk) 1862{ 1863 tsk->syscw++; 1864} 1865#else 1866static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 1867{ 1868} 1869 1870static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 1871{ 1872} 1873 1874static inline void inc_syscr(struct task_struct *tsk) 1875{ 1876} 1877 1878static inline void inc_syscw(struct task_struct *tsk) 1879{ 1880} 1881#endif 1882 1883#endif /* __KERNEL__ */ 1884 1885#endif