1 #ifndef _LINUX_SCHED_H 2 #define _LINUX_SCHED_H 3 4 /* 5 * cloning flags: 6 */ 7 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */ 8 #define CLONE_VM 0x00000100 /* set if VM shared between processes */ 9 #define CLONE_FS 0x00000200 /* set if fs info shared between processes */ 10 #define CLONE_FILES 0x00000400 /* set if open files shared between processes */ 11 #define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */ 12 #define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */ 13 #define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */ 14 #define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */ 15 #define CLONE_THREAD 0x00010000 /* Same thread group? */ 16 #define CLONE_NEWNS 0x00020000 /* New namespace group? */ 17 #define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */ 18 #define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */ 19 #define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */ 20 #define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */ 21 #define CLONE_DETACHED 0x00400000 /* Unused, ignored */ 22 #define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */ 23 #define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */ 24 /* 0x02000000 was previously the unused CLONE_STOPPED (Start in stopped state) 25 and is now available for re-use. */ 26 #define CLONE_NEWUTS 0x04000000 /* New utsname group? */ 27 #define CLONE_NEWIPC 0x08000000 /* New ipcs */ 28 #define CLONE_NEWUSER 0x10000000 /* New user namespace */ 29 #define CLONE_NEWPID 0x20000000 /* New pid namespace */ 30 #define CLONE_NEWNET 0x40000000 /* New network namespace */ 31 #define CLONE_IO 0x80000000 /* Clone io context */ 32 33 /* 34 * Scheduling policies 35 */ 36 #define SCHED_NORMAL 0 37 #define SCHED_FIFO 1 38 #define SCHED_RR 2 39 #define SCHED_BATCH 3 40 /* SCHED_ISO: reserved but not implemented yet */ 41 #define SCHED_IDLE 5 42 /* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */ 43 #define SCHED_RESET_ON_FORK 0x40000000 44 45 #ifdef __KERNEL__ 46 47 struct sched_param { 48 int sched_priority; 49 }; 50 51 #include <asm/param.h> /* for HZ */ 52 53 #include <linux/capability.h> 54 #include <linux/threads.h> 55 #include <linux/kernel.h> 56 #include <linux/types.h> 57 #include <linux/timex.h> 58 #include <linux/jiffies.h> 59 #include <linux/rbtree.h> 60 #include <linux/thread_info.h> 61 #include <linux/cpumask.h> 62 #include <linux/errno.h> 63 #include <linux/nodemask.h> 64 #include <linux/mm_types.h> 65 66 #include <asm/page.h> 67 #include <asm/ptrace.h> 68 #include <asm/cputime.h> 69 70 #include <linux/smp.h> 71 #include <linux/sem.h> 72 #include <linux/signal.h> 73 #include <linux/compiler.h> 74 #include <linux/completion.h> 75 #include <linux/pid.h> 76 #include <linux/percpu.h> 77 #include <linux/topology.h> 78 #include <linux/proportions.h> 79 #include <linux/seccomp.h> 80 #include <linux/rcupdate.h> 81 #include <linux/rculist.h> 82 #include <linux/rtmutex.h> 83 84 #include <linux/time.h> 85 #include <linux/param.h> 86 #include <linux/resource.h> 87 #include <linux/timer.h> 88 #include <linux/hrtimer.h> 89 #include <linux/task_io_accounting.h> 90 #include <linux/latencytop.h> 91 #include <linux/cred.h> 92 #include <linux/llist.h> 93 94 #include <asm/processor.h> 95 96 struct exec_domain; 97 struct futex_pi_state; 98 struct robust_list_head; 99 struct bio_list; 100 struct fs_struct; 101 struct perf_event_context; 102 struct blk_plug; 103 104 /* 105 * List of flags we want to share for kernel threads, 106 * if only because they are not used by them anyway. 107 */ 108 #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND) 109 110 /* 111 * These are the constant used to fake the fixed-point load-average 112 * counting. Some notes: 113 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 114 * a load-average precision of 10 bits integer + 11 bits fractional 115 * - if you want to count load-averages more often, you need more 116 * precision, or rounding will get you. With 2-second counting freq, 117 * the EXP_n values would be 1981, 2034 and 2043 if still using only 118 * 11 bit fractions. 119 */ 120 extern unsigned long avenrun[]; /* Load averages */ 121 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 122 123 #define FSHIFT 11 /* nr of bits of precision */ 124 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 125 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 126 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 127 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 128 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 129 130 #define CALC_LOAD(load,exp,n) \ 131 load *= exp; \ 132 load += n*(FIXED_1-exp); \ 133 load >>= FSHIFT; 134 135 extern unsigned long total_forks; 136 extern int nr_threads; 137 DECLARE_PER_CPU(unsigned long, process_counts); 138 extern int nr_processes(void); 139 extern unsigned long nr_running(void); 140 extern unsigned long nr_uninterruptible(void); 141 extern unsigned long nr_iowait(void); 142 extern unsigned long nr_iowait_cpu(int cpu); 143 extern unsigned long this_cpu_load(void); 144 145 146 extern void calc_global_load(unsigned long ticks); 147 148 extern unsigned long get_parent_ip(unsigned long addr); 149 150 struct seq_file; 151 struct cfs_rq; 152 struct task_group; 153 #ifdef CONFIG_SCHED_DEBUG 154 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 155 extern void proc_sched_set_task(struct task_struct *p); 156 extern void 157 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 158 #else 159 static inline void 160 proc_sched_show_task(struct task_struct *p, struct seq_file *m) 161 { 162 } 163 static inline void proc_sched_set_task(struct task_struct *p) 164 { 165 } 166 static inline void 167 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) 168 { 169 } 170 #endif 171 172 /* 173 * Task state bitmask. NOTE! These bits are also 174 * encoded in fs/proc/array.c: get_task_state(). 175 * 176 * We have two separate sets of flags: task->state 177 * is about runnability, while task->exit_state are 178 * about the task exiting. Confusing, but this way 179 * modifying one set can't modify the other one by 180 * mistake. 181 */ 182 #define TASK_RUNNING 0 183 #define TASK_INTERRUPTIBLE 1 184 #define TASK_UNINTERRUPTIBLE 2 185 #define __TASK_STOPPED 4 186 #define __TASK_TRACED 8 187 /* in tsk->exit_state */ 188 #define EXIT_ZOMBIE 16 189 #define EXIT_DEAD 32 190 /* in tsk->state again */ 191 #define TASK_DEAD 64 192 #define TASK_WAKEKILL 128 193 #define TASK_WAKING 256 194 #define TASK_STATE_MAX 512 195 196 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW" 197 198 extern char ___assert_task_state[1 - 2*!!( 199 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 200 201 /* Convenience macros for the sake of set_task_state */ 202 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 203 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 204 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 205 206 /* Convenience macros for the sake of wake_up */ 207 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 208 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 209 210 /* get_task_state() */ 211 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 212 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 213 __TASK_TRACED) 214 215 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 216 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 217 #define task_is_dead(task) ((task)->exit_state != 0) 218 #define task_is_stopped_or_traced(task) \ 219 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 220 #define task_contributes_to_load(task) \ 221 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 222 (task->flags & PF_FROZEN) == 0) 223 224 #define __set_task_state(tsk, state_value) \ 225 do { (tsk)->state = (state_value); } while (0) 226 #define set_task_state(tsk, state_value) \ 227 set_mb((tsk)->state, (state_value)) 228 229 /* 230 * set_current_state() includes a barrier so that the write of current->state 231 * is correctly serialised wrt the caller's subsequent test of whether to 232 * actually sleep: 233 * 234 * set_current_state(TASK_UNINTERRUPTIBLE); 235 * if (do_i_need_to_sleep()) 236 * schedule(); 237 * 238 * If the caller does not need such serialisation then use __set_current_state() 239 */ 240 #define __set_current_state(state_value) \ 241 do { current->state = (state_value); } while (0) 242 #define set_current_state(state_value) \ 243 set_mb(current->state, (state_value)) 244 245 /* Task command name length */ 246 #define TASK_COMM_LEN 16 247 248 #include <linux/spinlock.h> 249 250 /* 251 * This serializes "schedule()" and also protects 252 * the run-queue from deletions/modifications (but 253 * _adding_ to the beginning of the run-queue has 254 * a separate lock). 255 */ 256 extern rwlock_t tasklist_lock; 257 extern spinlock_t mmlist_lock; 258 259 struct task_struct; 260 261 #ifdef CONFIG_PROVE_RCU 262 extern int lockdep_tasklist_lock_is_held(void); 263 #endif /* #ifdef CONFIG_PROVE_RCU */ 264 265 extern void sched_init(void); 266 extern void sched_init_smp(void); 267 extern asmlinkage void schedule_tail(struct task_struct *prev); 268 extern void init_idle(struct task_struct *idle, int cpu); 269 extern void init_idle_bootup_task(struct task_struct *idle); 270 271 extern int runqueue_is_locked(int cpu); 272 273 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ) 274 extern void select_nohz_load_balancer(int stop_tick); 275 extern void set_cpu_sd_state_idle(void); 276 extern int get_nohz_timer_target(void); 277 #else 278 static inline void select_nohz_load_balancer(int stop_tick) { } 279 static inline void set_cpu_sd_state_idle(void) { } 280 #endif 281 282 /* 283 * Only dump TASK_* tasks. (0 for all tasks) 284 */ 285 extern void show_state_filter(unsigned long state_filter); 286 287 static inline void show_state(void) 288 { 289 show_state_filter(0); 290 } 291 292 extern void show_regs(struct pt_regs *); 293 294 /* 295 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 296 * task), SP is the stack pointer of the first frame that should be shown in the back 297 * trace (or NULL if the entire call-chain of the task should be shown). 298 */ 299 extern void show_stack(struct task_struct *task, unsigned long *sp); 300 301 void io_schedule(void); 302 long io_schedule_timeout(long timeout); 303 304 extern void cpu_init (void); 305 extern void trap_init(void); 306 extern void update_process_times(int user); 307 extern void scheduler_tick(void); 308 309 extern void sched_show_task(struct task_struct *p); 310 311 #ifdef CONFIG_LOCKUP_DETECTOR 312 extern void touch_softlockup_watchdog(void); 313 extern void touch_softlockup_watchdog_sync(void); 314 extern void touch_all_softlockup_watchdogs(void); 315 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 316 void __user *buffer, 317 size_t *lenp, loff_t *ppos); 318 extern unsigned int softlockup_panic; 319 void lockup_detector_init(void); 320 #else 321 static inline void touch_softlockup_watchdog(void) 322 { 323 } 324 static inline void touch_softlockup_watchdog_sync(void) 325 { 326 } 327 static inline void touch_all_softlockup_watchdogs(void) 328 { 329 } 330 static inline void lockup_detector_init(void) 331 { 332 } 333 #endif 334 335 #ifdef CONFIG_DETECT_HUNG_TASK 336 extern unsigned int sysctl_hung_task_panic; 337 extern unsigned long sysctl_hung_task_check_count; 338 extern unsigned long sysctl_hung_task_timeout_secs; 339 extern unsigned long sysctl_hung_task_warnings; 340 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, 341 void __user *buffer, 342 size_t *lenp, loff_t *ppos); 343 #else 344 /* Avoid need for ifdefs elsewhere in the code */ 345 enum { sysctl_hung_task_timeout_secs = 0 }; 346 #endif 347 348 /* Attach to any functions which should be ignored in wchan output. */ 349 #define __sched __attribute__((__section__(".sched.text"))) 350 351 /* Linker adds these: start and end of __sched functions */ 352 extern char __sched_text_start[], __sched_text_end[]; 353 354 /* Is this address in the __sched functions? */ 355 extern int in_sched_functions(unsigned long addr); 356 357 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 358 extern signed long schedule_timeout(signed long timeout); 359 extern signed long schedule_timeout_interruptible(signed long timeout); 360 extern signed long schedule_timeout_killable(signed long timeout); 361 extern signed long schedule_timeout_uninterruptible(signed long timeout); 362 asmlinkage void schedule(void); 363 extern void schedule_preempt_disabled(void); 364 extern int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner); 365 366 struct nsproxy; 367 struct user_namespace; 368 369 /* 370 * Default maximum number of active map areas, this limits the number of vmas 371 * per mm struct. Users can overwrite this number by sysctl but there is a 372 * problem. 373 * 374 * When a program's coredump is generated as ELF format, a section is created 375 * per a vma. In ELF, the number of sections is represented in unsigned short. 376 * This means the number of sections should be smaller than 65535 at coredump. 377 * Because the kernel adds some informative sections to a image of program at 378 * generating coredump, we need some margin. The number of extra sections is 379 * 1-3 now and depends on arch. We use "5" as safe margin, here. 380 */ 381 #define MAPCOUNT_ELF_CORE_MARGIN (5) 382 #define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) 383 384 extern int sysctl_max_map_count; 385 386 #include <linux/aio.h> 387 388 #ifdef CONFIG_MMU 389 extern void arch_pick_mmap_layout(struct mm_struct *mm); 390 extern unsigned long 391 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 392 unsigned long, unsigned long); 393 extern unsigned long 394 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 395 unsigned long len, unsigned long pgoff, 396 unsigned long flags); 397 extern void arch_unmap_area(struct mm_struct *, unsigned long); 398 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); 399 #else 400 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 401 #endif 402 403 404 extern void set_dumpable(struct mm_struct *mm, int value); 405 extern int get_dumpable(struct mm_struct *mm); 406 407 /* mm flags */ 408 /* dumpable bits */ 409 #define MMF_DUMPABLE 0 /* core dump is permitted */ 410 #define MMF_DUMP_SECURELY 1 /* core file is readable only by root */ 411 412 #define MMF_DUMPABLE_BITS 2 413 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 414 415 /* coredump filter bits */ 416 #define MMF_DUMP_ANON_PRIVATE 2 417 #define MMF_DUMP_ANON_SHARED 3 418 #define MMF_DUMP_MAPPED_PRIVATE 4 419 #define MMF_DUMP_MAPPED_SHARED 5 420 #define MMF_DUMP_ELF_HEADERS 6 421 #define MMF_DUMP_HUGETLB_PRIVATE 7 422 #define MMF_DUMP_HUGETLB_SHARED 8 423 424 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 425 #define MMF_DUMP_FILTER_BITS 7 426 #define MMF_DUMP_FILTER_MASK \ 427 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 428 #define MMF_DUMP_FILTER_DEFAULT \ 429 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 430 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 431 432 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 433 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 434 #else 435 # define MMF_DUMP_MASK_DEFAULT_ELF 0 436 #endif 437 /* leave room for more dump flags */ 438 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 439 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 440 441 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 442 443 struct sighand_struct { 444 atomic_t count; 445 struct k_sigaction action[_NSIG]; 446 spinlock_t siglock; 447 wait_queue_head_t signalfd_wqh; 448 }; 449 450 struct pacct_struct { 451 int ac_flag; 452 long ac_exitcode; 453 unsigned long ac_mem; 454 cputime_t ac_utime, ac_stime; 455 unsigned long ac_minflt, ac_majflt; 456 }; 457 458 struct cpu_itimer { 459 cputime_t expires; 460 cputime_t incr; 461 u32 error; 462 u32 incr_error; 463 }; 464 465 /** 466 * struct task_cputime - collected CPU time counts 467 * @utime: time spent in user mode, in &cputime_t units 468 * @stime: time spent in kernel mode, in &cputime_t units 469 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 470 * 471 * This structure groups together three kinds of CPU time that are 472 * tracked for threads and thread groups. Most things considering 473 * CPU time want to group these counts together and treat all three 474 * of them in parallel. 475 */ 476 struct task_cputime { 477 cputime_t utime; 478 cputime_t stime; 479 unsigned long long sum_exec_runtime; 480 }; 481 /* Alternate field names when used to cache expirations. */ 482 #define prof_exp stime 483 #define virt_exp utime 484 #define sched_exp sum_exec_runtime 485 486 #define INIT_CPUTIME \ 487 (struct task_cputime) { \ 488 .utime = 0, \ 489 .stime = 0, \ 490 .sum_exec_runtime = 0, \ 491 } 492 493 /* 494 * Disable preemption until the scheduler is running. 495 * Reset by start_kernel()->sched_init()->init_idle(). 496 * 497 * We include PREEMPT_ACTIVE to avoid cond_resched() from working 498 * before the scheduler is active -- see should_resched(). 499 */ 500 #define INIT_PREEMPT_COUNT (1 + PREEMPT_ACTIVE) 501 502 /** 503 * struct thread_group_cputimer - thread group interval timer counts 504 * @cputime: thread group interval timers. 505 * @running: non-zero when there are timers running and 506 * @cputime receives updates. 507 * @lock: lock for fields in this struct. 508 * 509 * This structure contains the version of task_cputime, above, that is 510 * used for thread group CPU timer calculations. 511 */ 512 struct thread_group_cputimer { 513 struct task_cputime cputime; 514 int running; 515 raw_spinlock_t lock; 516 }; 517 518 #include <linux/rwsem.h> 519 struct autogroup; 520 521 /* 522 * NOTE! "signal_struct" does not have its own 523 * locking, because a shared signal_struct always 524 * implies a shared sighand_struct, so locking 525 * sighand_struct is always a proper superset of 526 * the locking of signal_struct. 527 */ 528 struct signal_struct { 529 atomic_t sigcnt; 530 atomic_t live; 531 int nr_threads; 532 533 wait_queue_head_t wait_chldexit; /* for wait4() */ 534 535 /* current thread group signal load-balancing target: */ 536 struct task_struct *curr_target; 537 538 /* shared signal handling: */ 539 struct sigpending shared_pending; 540 541 /* thread group exit support */ 542 int group_exit_code; 543 /* overloaded: 544 * - notify group_exit_task when ->count is equal to notify_count 545 * - everyone except group_exit_task is stopped during signal delivery 546 * of fatal signals, group_exit_task processes the signal. 547 */ 548 int notify_count; 549 struct task_struct *group_exit_task; 550 551 /* thread group stop support, overloads group_exit_code too */ 552 int group_stop_count; 553 unsigned int flags; /* see SIGNAL_* flags below */ 554 555 /* POSIX.1b Interval Timers */ 556 struct list_head posix_timers; 557 558 /* ITIMER_REAL timer for the process */ 559 struct hrtimer real_timer; 560 struct pid *leader_pid; 561 ktime_t it_real_incr; 562 563 /* 564 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 565 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 566 * values are defined to 0 and 1 respectively 567 */ 568 struct cpu_itimer it[2]; 569 570 /* 571 * Thread group totals for process CPU timers. 572 * See thread_group_cputimer(), et al, for details. 573 */ 574 struct thread_group_cputimer cputimer; 575 576 /* Earliest-expiration cache. */ 577 struct task_cputime cputime_expires; 578 579 struct list_head cpu_timers[3]; 580 581 struct pid *tty_old_pgrp; 582 583 /* boolean value for session group leader */ 584 int leader; 585 586 struct tty_struct *tty; /* NULL if no tty */ 587 588 #ifdef CONFIG_SCHED_AUTOGROUP 589 struct autogroup *autogroup; 590 #endif 591 /* 592 * Cumulative resource counters for dead threads in the group, 593 * and for reaped dead child processes forked by this group. 594 * Live threads maintain their own counters and add to these 595 * in __exit_signal, except for the group leader. 596 */ 597 cputime_t utime, stime, cutime, cstime; 598 cputime_t gtime; 599 cputime_t cgtime; 600 #ifndef CONFIG_VIRT_CPU_ACCOUNTING 601 cputime_t prev_utime, prev_stime; 602 #endif 603 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 604 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 605 unsigned long inblock, oublock, cinblock, coublock; 606 unsigned long maxrss, cmaxrss; 607 struct task_io_accounting ioac; 608 609 /* 610 * Cumulative ns of schedule CPU time fo dead threads in the 611 * group, not including a zombie group leader, (This only differs 612 * from jiffies_to_ns(utime + stime) if sched_clock uses something 613 * other than jiffies.) 614 */ 615 unsigned long long sum_sched_runtime; 616 617 /* 618 * We don't bother to synchronize most readers of this at all, 619 * because there is no reader checking a limit that actually needs 620 * to get both rlim_cur and rlim_max atomically, and either one 621 * alone is a single word that can safely be read normally. 622 * getrlimit/setrlimit use task_lock(current->group_leader) to 623 * protect this instead of the siglock, because they really 624 * have no need to disable irqs. 625 */ 626 struct rlimit rlim[RLIM_NLIMITS]; 627 628 #ifdef CONFIG_BSD_PROCESS_ACCT 629 struct pacct_struct pacct; /* per-process accounting information */ 630 #endif 631 #ifdef CONFIG_TASKSTATS 632 struct taskstats *stats; 633 #endif 634 #ifdef CONFIG_AUDIT 635 unsigned audit_tty; 636 struct tty_audit_buf *tty_audit_buf; 637 #endif 638 #ifdef CONFIG_CGROUPS 639 /* 640 * group_rwsem prevents new tasks from entering the threadgroup and 641 * member tasks from exiting,a more specifically, setting of 642 * PF_EXITING. fork and exit paths are protected with this rwsem 643 * using threadgroup_change_begin/end(). Users which require 644 * threadgroup to remain stable should use threadgroup_[un]lock() 645 * which also takes care of exec path. Currently, cgroup is the 646 * only user. 647 */ 648 struct rw_semaphore group_rwsem; 649 #endif 650 651 int oom_adj; /* OOM kill score adjustment (bit shift) */ 652 int oom_score_adj; /* OOM kill score adjustment */ 653 int oom_score_adj_min; /* OOM kill score adjustment minimum value. 654 * Only settable by CAP_SYS_RESOURCE. */ 655 656 struct mutex cred_guard_mutex; /* guard against foreign influences on 657 * credential calculations 658 * (notably. ptrace) */ 659 }; 660 661 /* Context switch must be unlocked if interrupts are to be enabled */ 662 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW 663 # define __ARCH_WANT_UNLOCKED_CTXSW 664 #endif 665 666 /* 667 * Bits in flags field of signal_struct. 668 */ 669 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 670 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 671 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 672 /* 673 * Pending notifications to parent. 674 */ 675 #define SIGNAL_CLD_STOPPED 0x00000010 676 #define SIGNAL_CLD_CONTINUED 0x00000020 677 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 678 679 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 680 681 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 682 static inline int signal_group_exit(const struct signal_struct *sig) 683 { 684 return (sig->flags & SIGNAL_GROUP_EXIT) || 685 (sig->group_exit_task != NULL); 686 } 687 688 /* 689 * Some day this will be a full-fledged user tracking system.. 690 */ 691 struct user_struct { 692 atomic_t __count; /* reference count */ 693 atomic_t processes; /* How many processes does this user have? */ 694 atomic_t files; /* How many open files does this user have? */ 695 atomic_t sigpending; /* How many pending signals does this user have? */ 696 #ifdef CONFIG_INOTIFY_USER 697 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 698 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 699 #endif 700 #ifdef CONFIG_FANOTIFY 701 atomic_t fanotify_listeners; 702 #endif 703 #ifdef CONFIG_EPOLL 704 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 705 #endif 706 #ifdef CONFIG_POSIX_MQUEUE 707 /* protected by mq_lock */ 708 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 709 #endif 710 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 711 712 #ifdef CONFIG_KEYS 713 struct key *uid_keyring; /* UID specific keyring */ 714 struct key *session_keyring; /* UID's default session keyring */ 715 #endif 716 717 /* Hash table maintenance information */ 718 struct hlist_node uidhash_node; 719 uid_t uid; 720 struct user_namespace *user_ns; 721 722 #ifdef CONFIG_PERF_EVENTS 723 atomic_long_t locked_vm; 724 #endif 725 }; 726 727 extern int uids_sysfs_init(void); 728 729 extern struct user_struct *find_user(uid_t); 730 731 extern struct user_struct root_user; 732 #define INIT_USER (&root_user) 733 734 735 struct backing_dev_info; 736 struct reclaim_state; 737 738 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 739 struct sched_info { 740 /* cumulative counters */ 741 unsigned long pcount; /* # of times run on this cpu */ 742 unsigned long long run_delay; /* time spent waiting on a runqueue */ 743 744 /* timestamps */ 745 unsigned long long last_arrival,/* when we last ran on a cpu */ 746 last_queued; /* when we were last queued to run */ 747 }; 748 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ 749 750 #ifdef CONFIG_TASK_DELAY_ACCT 751 struct task_delay_info { 752 spinlock_t lock; 753 unsigned int flags; /* Private per-task flags */ 754 755 /* For each stat XXX, add following, aligned appropriately 756 * 757 * struct timespec XXX_start, XXX_end; 758 * u64 XXX_delay; 759 * u32 XXX_count; 760 * 761 * Atomicity of updates to XXX_delay, XXX_count protected by 762 * single lock above (split into XXX_lock if contention is an issue). 763 */ 764 765 /* 766 * XXX_count is incremented on every XXX operation, the delay 767 * associated with the operation is added to XXX_delay. 768 * XXX_delay contains the accumulated delay time in nanoseconds. 769 */ 770 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ 771 u64 blkio_delay; /* wait for sync block io completion */ 772 u64 swapin_delay; /* wait for swapin block io completion */ 773 u32 blkio_count; /* total count of the number of sync block */ 774 /* io operations performed */ 775 u32 swapin_count; /* total count of the number of swapin block */ 776 /* io operations performed */ 777 778 struct timespec freepages_start, freepages_end; 779 u64 freepages_delay; /* wait for memory reclaim */ 780 u32 freepages_count; /* total count of memory reclaim */ 781 }; 782 #endif /* CONFIG_TASK_DELAY_ACCT */ 783 784 static inline int sched_info_on(void) 785 { 786 #ifdef CONFIG_SCHEDSTATS 787 return 1; 788 #elif defined(CONFIG_TASK_DELAY_ACCT) 789 extern int delayacct_on; 790 return delayacct_on; 791 #else 792 return 0; 793 #endif 794 } 795 796 enum cpu_idle_type { 797 CPU_IDLE, 798 CPU_NOT_IDLE, 799 CPU_NEWLY_IDLE, 800 CPU_MAX_IDLE_TYPES 801 }; 802 803 /* 804 * Increase resolution of nice-level calculations for 64-bit architectures. 805 * The extra resolution improves shares distribution and load balancing of 806 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 807 * hierarchies, especially on larger systems. This is not a user-visible change 808 * and does not change the user-interface for setting shares/weights. 809 * 810 * We increase resolution only if we have enough bits to allow this increased 811 * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution 812 * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the 813 * increased costs. 814 */ 815 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */ 816 # define SCHED_LOAD_RESOLUTION 10 817 # define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION) 818 # define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION) 819 #else 820 # define SCHED_LOAD_RESOLUTION 0 821 # define scale_load(w) (w) 822 # define scale_load_down(w) (w) 823 #endif 824 825 #define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION) 826 #define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT) 827 828 /* 829 * Increase resolution of cpu_power calculations 830 */ 831 #define SCHED_POWER_SHIFT 10 832 #define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT) 833 834 /* 835 * sched-domains (multiprocessor balancing) declarations: 836 */ 837 #ifdef CONFIG_SMP 838 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 839 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 840 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 841 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 842 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 843 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 844 #define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */ 845 #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ 846 #define SD_POWERSAVINGS_BALANCE 0x0100 /* Balance for power savings */ 847 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 848 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 849 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 850 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 851 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 852 853 enum powersavings_balance_level { 854 POWERSAVINGS_BALANCE_NONE = 0, /* No power saving load balance */ 855 POWERSAVINGS_BALANCE_BASIC, /* Fill one thread/core/package 856 * first for long running threads 857 */ 858 POWERSAVINGS_BALANCE_WAKEUP, /* Also bias task wakeups to semi-idle 859 * cpu package for power savings 860 */ 861 MAX_POWERSAVINGS_BALANCE_LEVELS 862 }; 863 864 extern int sched_mc_power_savings, sched_smt_power_savings; 865 866 static inline int sd_balance_for_mc_power(void) 867 { 868 if (sched_smt_power_savings) 869 return SD_POWERSAVINGS_BALANCE; 870 871 if (!sched_mc_power_savings) 872 return SD_PREFER_SIBLING; 873 874 return 0; 875 } 876 877 static inline int sd_balance_for_package_power(void) 878 { 879 if (sched_mc_power_savings | sched_smt_power_savings) 880 return SD_POWERSAVINGS_BALANCE; 881 882 return SD_PREFER_SIBLING; 883 } 884 885 extern int __weak arch_sd_sibiling_asym_packing(void); 886 887 /* 888 * Optimise SD flags for power savings: 889 * SD_BALANCE_NEWIDLE helps aggressive task consolidation and power savings. 890 * Keep default SD flags if sched_{smt,mc}_power_saving=0 891 */ 892 893 static inline int sd_power_saving_flags(void) 894 { 895 if (sched_mc_power_savings | sched_smt_power_savings) 896 return SD_BALANCE_NEWIDLE; 897 898 return 0; 899 } 900 901 struct sched_group_power { 902 atomic_t ref; 903 /* 904 * CPU power of this group, SCHED_LOAD_SCALE being max power for a 905 * single CPU. 906 */ 907 unsigned int power, power_orig; 908 unsigned long next_update; 909 /* 910 * Number of busy cpus in this group. 911 */ 912 atomic_t nr_busy_cpus; 913 }; 914 915 struct sched_group { 916 struct sched_group *next; /* Must be a circular list */ 917 atomic_t ref; 918 919 unsigned int group_weight; 920 struct sched_group_power *sgp; 921 922 /* 923 * The CPUs this group covers. 924 * 925 * NOTE: this field is variable length. (Allocated dynamically 926 * by attaching extra space to the end of the structure, 927 * depending on how many CPUs the kernel has booted up with) 928 */ 929 unsigned long cpumask[0]; 930 }; 931 932 static inline struct cpumask *sched_group_cpus(struct sched_group *sg) 933 { 934 return to_cpumask(sg->cpumask); 935 } 936 937 /** 938 * group_first_cpu - Returns the first cpu in the cpumask of a sched_group. 939 * @group: The group whose first cpu is to be returned. 940 */ 941 static inline unsigned int group_first_cpu(struct sched_group *group) 942 { 943 return cpumask_first(sched_group_cpus(group)); 944 } 945 946 struct sched_domain_attr { 947 int relax_domain_level; 948 }; 949 950 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 951 .relax_domain_level = -1, \ 952 } 953 954 extern int sched_domain_level_max; 955 956 struct sched_domain { 957 /* These fields must be setup */ 958 struct sched_domain *parent; /* top domain must be null terminated */ 959 struct sched_domain *child; /* bottom domain must be null terminated */ 960 struct sched_group *groups; /* the balancing groups of the domain */ 961 unsigned long min_interval; /* Minimum balance interval ms */ 962 unsigned long max_interval; /* Maximum balance interval ms */ 963 unsigned int busy_factor; /* less balancing by factor if busy */ 964 unsigned int imbalance_pct; /* No balance until over watermark */ 965 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 966 unsigned int busy_idx; 967 unsigned int idle_idx; 968 unsigned int newidle_idx; 969 unsigned int wake_idx; 970 unsigned int forkexec_idx; 971 unsigned int smt_gain; 972 int flags; /* See SD_* */ 973 int level; 974 975 /* Runtime fields. */ 976 unsigned long last_balance; /* init to jiffies. units in jiffies */ 977 unsigned int balance_interval; /* initialise to 1. units in ms. */ 978 unsigned int nr_balance_failed; /* initialise to 0 */ 979 980 u64 last_update; 981 982 #ifdef CONFIG_SCHEDSTATS 983 /* load_balance() stats */ 984 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 985 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 986 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 987 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 988 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 989 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 990 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 991 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 992 993 /* Active load balancing */ 994 unsigned int alb_count; 995 unsigned int alb_failed; 996 unsigned int alb_pushed; 997 998 /* SD_BALANCE_EXEC stats */ 999 unsigned int sbe_count; 1000 unsigned int sbe_balanced; 1001 unsigned int sbe_pushed; 1002 1003 /* SD_BALANCE_FORK stats */ 1004 unsigned int sbf_count; 1005 unsigned int sbf_balanced; 1006 unsigned int sbf_pushed; 1007 1008 /* try_to_wake_up() stats */ 1009 unsigned int ttwu_wake_remote; 1010 unsigned int ttwu_move_affine; 1011 unsigned int ttwu_move_balance; 1012 #endif 1013 #ifdef CONFIG_SCHED_DEBUG 1014 char *name; 1015 #endif 1016 union { 1017 void *private; /* used during construction */ 1018 struct rcu_head rcu; /* used during destruction */ 1019 }; 1020 1021 unsigned int span_weight; 1022 /* 1023 * Span of all CPUs in this domain. 1024 * 1025 * NOTE: this field is variable length. (Allocated dynamically 1026 * by attaching extra space to the end of the structure, 1027 * depending on how many CPUs the kernel has booted up with) 1028 */ 1029 unsigned long span[0]; 1030 }; 1031 1032 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 1033 { 1034 return to_cpumask(sd->span); 1035 } 1036 1037 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1038 struct sched_domain_attr *dattr_new); 1039 1040 /* Allocate an array of sched domains, for partition_sched_domains(). */ 1041 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 1042 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 1043 1044 /* Test a flag in parent sched domain */ 1045 static inline int test_sd_parent(struct sched_domain *sd, int flag) 1046 { 1047 if (sd->parent && (sd->parent->flags & flag)) 1048 return 1; 1049 1050 return 0; 1051 } 1052 1053 unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu); 1054 unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu); 1055 1056 bool cpus_share_cache(int this_cpu, int that_cpu); 1057 1058 #else /* CONFIG_SMP */ 1059 1060 struct sched_domain_attr; 1061 1062 static inline void 1063 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1064 struct sched_domain_attr *dattr_new) 1065 { 1066 } 1067 1068 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1069 { 1070 return true; 1071 } 1072 1073 #endif /* !CONFIG_SMP */ 1074 1075 1076 struct io_context; /* See blkdev.h */ 1077 1078 1079 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1080 extern void prefetch_stack(struct task_struct *t); 1081 #else 1082 static inline void prefetch_stack(struct task_struct *t) { } 1083 #endif 1084 1085 struct audit_context; /* See audit.c */ 1086 struct mempolicy; 1087 struct pipe_inode_info; 1088 struct uts_namespace; 1089 1090 struct rq; 1091 struct sched_domain; 1092 1093 /* 1094 * wake flags 1095 */ 1096 #define WF_SYNC 0x01 /* waker goes to sleep after wakup */ 1097 #define WF_FORK 0x02 /* child wakeup after fork */ 1098 #define WF_MIGRATED 0x04 /* internal use, task got migrated */ 1099 1100 #define ENQUEUE_WAKEUP 1 1101 #define ENQUEUE_HEAD 2 1102 #ifdef CONFIG_SMP 1103 #define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */ 1104 #else 1105 #define ENQUEUE_WAKING 0 1106 #endif 1107 1108 #define DEQUEUE_SLEEP 1 1109 1110 struct sched_class { 1111 const struct sched_class *next; 1112 1113 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 1114 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 1115 void (*yield_task) (struct rq *rq); 1116 bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt); 1117 1118 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags); 1119 1120 struct task_struct * (*pick_next_task) (struct rq *rq); 1121 void (*put_prev_task) (struct rq *rq, struct task_struct *p); 1122 1123 #ifdef CONFIG_SMP 1124 int (*select_task_rq)(struct task_struct *p, int sd_flag, int flags); 1125 1126 void (*pre_schedule) (struct rq *this_rq, struct task_struct *task); 1127 void (*post_schedule) (struct rq *this_rq); 1128 void (*task_waking) (struct task_struct *task); 1129 void (*task_woken) (struct rq *this_rq, struct task_struct *task); 1130 1131 void (*set_cpus_allowed)(struct task_struct *p, 1132 const struct cpumask *newmask); 1133 1134 void (*rq_online)(struct rq *rq); 1135 void (*rq_offline)(struct rq *rq); 1136 #endif 1137 1138 void (*set_curr_task) (struct rq *rq); 1139 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued); 1140 void (*task_fork) (struct task_struct *p); 1141 1142 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 1143 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 1144 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 1145 int oldprio); 1146 1147 unsigned int (*get_rr_interval) (struct rq *rq, 1148 struct task_struct *task); 1149 1150 #ifdef CONFIG_FAIR_GROUP_SCHED 1151 void (*task_move_group) (struct task_struct *p, int on_rq); 1152 #endif 1153 }; 1154 1155 struct load_weight { 1156 unsigned long weight, inv_weight; 1157 }; 1158 1159 #ifdef CONFIG_SCHEDSTATS 1160 struct sched_statistics { 1161 u64 wait_start; 1162 u64 wait_max; 1163 u64 wait_count; 1164 u64 wait_sum; 1165 u64 iowait_count; 1166 u64 iowait_sum; 1167 1168 u64 sleep_start; 1169 u64 sleep_max; 1170 s64 sum_sleep_runtime; 1171 1172 u64 block_start; 1173 u64 block_max; 1174 u64 exec_max; 1175 u64 slice_max; 1176 1177 u64 nr_migrations_cold; 1178 u64 nr_failed_migrations_affine; 1179 u64 nr_failed_migrations_running; 1180 u64 nr_failed_migrations_hot; 1181 u64 nr_forced_migrations; 1182 1183 u64 nr_wakeups; 1184 u64 nr_wakeups_sync; 1185 u64 nr_wakeups_migrate; 1186 u64 nr_wakeups_local; 1187 u64 nr_wakeups_remote; 1188 u64 nr_wakeups_affine; 1189 u64 nr_wakeups_affine_attempts; 1190 u64 nr_wakeups_passive; 1191 u64 nr_wakeups_idle; 1192 }; 1193 #endif 1194 1195 struct sched_entity { 1196 struct load_weight load; /* for load-balancing */ 1197 struct rb_node run_node; 1198 struct list_head group_node; 1199 unsigned int on_rq; 1200 1201 u64 exec_start; 1202 u64 sum_exec_runtime; 1203 u64 vruntime; 1204 u64 prev_sum_exec_runtime; 1205 1206 u64 nr_migrations; 1207 1208 #ifdef CONFIG_SCHEDSTATS 1209 struct sched_statistics statistics; 1210 #endif 1211 1212 #ifdef CONFIG_FAIR_GROUP_SCHED 1213 struct sched_entity *parent; 1214 /* rq on which this entity is (to be) queued: */ 1215 struct cfs_rq *cfs_rq; 1216 /* rq "owned" by this entity/group: */ 1217 struct cfs_rq *my_q; 1218 #endif 1219 }; 1220 1221 struct sched_rt_entity { 1222 struct list_head run_list; 1223 unsigned long timeout; 1224 unsigned int time_slice; 1225 int nr_cpus_allowed; 1226 1227 struct sched_rt_entity *back; 1228 #ifdef CONFIG_RT_GROUP_SCHED 1229 struct sched_rt_entity *parent; 1230 /* rq on which this entity is (to be) queued: */ 1231 struct rt_rq *rt_rq; 1232 /* rq "owned" by this entity/group: */ 1233 struct rt_rq *my_q; 1234 #endif 1235 }; 1236 1237 /* 1238 * default timeslice is 100 msecs (used only for SCHED_RR tasks). 1239 * Timeslices get refilled after they expire. 1240 */ 1241 #define RR_TIMESLICE (100 * HZ / 1000) 1242 1243 struct rcu_node; 1244 1245 enum perf_event_task_context { 1246 perf_invalid_context = -1, 1247 perf_hw_context = 0, 1248 perf_sw_context, 1249 perf_nr_task_contexts, 1250 }; 1251 1252 struct task_struct { 1253 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1254 void *stack; 1255 atomic_t usage; 1256 unsigned int flags; /* per process flags, defined below */ 1257 unsigned int ptrace; 1258 1259 #ifdef CONFIG_SMP 1260 struct llist_node wake_entry; 1261 int on_cpu; 1262 #endif 1263 int on_rq; 1264 1265 int prio, static_prio, normal_prio; 1266 unsigned int rt_priority; 1267 const struct sched_class *sched_class; 1268 struct sched_entity se; 1269 struct sched_rt_entity rt; 1270 1271 #ifdef CONFIG_PREEMPT_NOTIFIERS 1272 /* list of struct preempt_notifier: */ 1273 struct hlist_head preempt_notifiers; 1274 #endif 1275 1276 /* 1277 * fpu_counter contains the number of consecutive context switches 1278 * that the FPU is used. If this is over a threshold, the lazy fpu 1279 * saving becomes unlazy to save the trap. This is an unsigned char 1280 * so that after 256 times the counter wraps and the behavior turns 1281 * lazy again; this to deal with bursty apps that only use FPU for 1282 * a short time 1283 */ 1284 unsigned char fpu_counter; 1285 #ifdef CONFIG_BLK_DEV_IO_TRACE 1286 unsigned int btrace_seq; 1287 #endif 1288 1289 unsigned int policy; 1290 cpumask_t cpus_allowed; 1291 1292 #ifdef CONFIG_PREEMPT_RCU 1293 int rcu_read_lock_nesting; 1294 char rcu_read_unlock_special; 1295 struct list_head rcu_node_entry; 1296 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1297 #ifdef CONFIG_TREE_PREEMPT_RCU 1298 struct rcu_node *rcu_blocked_node; 1299 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1300 #ifdef CONFIG_RCU_BOOST 1301 struct rt_mutex *rcu_boost_mutex; 1302 #endif /* #ifdef CONFIG_RCU_BOOST */ 1303 1304 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) 1305 struct sched_info sched_info; 1306 #endif 1307 1308 struct list_head tasks; 1309 #ifdef CONFIG_SMP 1310 struct plist_node pushable_tasks; 1311 #endif 1312 1313 struct mm_struct *mm, *active_mm; 1314 #ifdef CONFIG_COMPAT_BRK 1315 unsigned brk_randomized:1; 1316 #endif 1317 #if defined(SPLIT_RSS_COUNTING) 1318 struct task_rss_stat rss_stat; 1319 #endif 1320 /* task state */ 1321 int exit_state; 1322 int exit_code, exit_signal; 1323 int pdeath_signal; /* The signal sent when the parent dies */ 1324 unsigned int jobctl; /* JOBCTL_*, siglock protected */ 1325 /* ??? */ 1326 unsigned int personality; 1327 unsigned did_exec:1; 1328 unsigned in_execve:1; /* Tell the LSMs that the process is doing an 1329 * execve */ 1330 unsigned in_iowait:1; 1331 1332 1333 /* Revert to default priority/policy when forking */ 1334 unsigned sched_reset_on_fork:1; 1335 unsigned sched_contributes_to_load:1; 1336 1337 #ifdef CONFIG_GENERIC_HARDIRQS 1338 /* IRQ handler threads */ 1339 unsigned irq_thread:1; 1340 #endif 1341 1342 pid_t pid; 1343 pid_t tgid; 1344 1345 #ifdef CONFIG_CC_STACKPROTECTOR 1346 /* Canary value for the -fstack-protector gcc feature */ 1347 unsigned long stack_canary; 1348 #endif 1349 1350 /* 1351 * pointers to (original) parent process, youngest child, younger sibling, 1352 * older sibling, respectively. (p->father can be replaced with 1353 * p->real_parent->pid) 1354 */ 1355 struct task_struct __rcu *real_parent; /* real parent process */ 1356 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1357 /* 1358 * children/sibling forms the list of my natural children 1359 */ 1360 struct list_head children; /* list of my children */ 1361 struct list_head sibling; /* linkage in my parent's children list */ 1362 struct task_struct *group_leader; /* threadgroup leader */ 1363 1364 /* 1365 * ptraced is the list of tasks this task is using ptrace on. 1366 * This includes both natural children and PTRACE_ATTACH targets. 1367 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1368 */ 1369 struct list_head ptraced; 1370 struct list_head ptrace_entry; 1371 1372 /* PID/PID hash table linkage. */ 1373 struct pid_link pids[PIDTYPE_MAX]; 1374 struct list_head thread_group; 1375 1376 struct completion *vfork_done; /* for vfork() */ 1377 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1378 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1379 1380 cputime_t utime, stime, utimescaled, stimescaled; 1381 cputime_t gtime; 1382 #ifndef CONFIG_VIRT_CPU_ACCOUNTING 1383 cputime_t prev_utime, prev_stime; 1384 #endif 1385 unsigned long nvcsw, nivcsw; /* context switch counts */ 1386 struct timespec start_time; /* monotonic time */ 1387 struct timespec real_start_time; /* boot based time */ 1388 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1389 unsigned long min_flt, maj_flt; 1390 1391 struct task_cputime cputime_expires; 1392 struct list_head cpu_timers[3]; 1393 1394 /* process credentials */ 1395 const struct cred __rcu *real_cred; /* objective and real subjective task 1396 * credentials (COW) */ 1397 const struct cred __rcu *cred; /* effective (overridable) subjective task 1398 * credentials (COW) */ 1399 struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */ 1400 1401 char comm[TASK_COMM_LEN]; /* executable name excluding path 1402 - access with [gs]et_task_comm (which lock 1403 it with task_lock()) 1404 - initialized normally by setup_new_exec */ 1405 /* file system info */ 1406 int link_count, total_link_count; 1407 #ifdef CONFIG_SYSVIPC 1408 /* ipc stuff */ 1409 struct sysv_sem sysvsem; 1410 #endif 1411 #ifdef CONFIG_DETECT_HUNG_TASK 1412 /* hung task detection */ 1413 unsigned long last_switch_count; 1414 #endif 1415 /* CPU-specific state of this task */ 1416 struct thread_struct thread; 1417 /* filesystem information */ 1418 struct fs_struct *fs; 1419 /* open file information */ 1420 struct files_struct *files; 1421 /* namespaces */ 1422 struct nsproxy *nsproxy; 1423 /* signal handlers */ 1424 struct signal_struct *signal; 1425 struct sighand_struct *sighand; 1426 1427 sigset_t blocked, real_blocked; 1428 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1429 struct sigpending pending; 1430 1431 unsigned long sas_ss_sp; 1432 size_t sas_ss_size; 1433 int (*notifier)(void *priv); 1434 void *notifier_data; 1435 sigset_t *notifier_mask; 1436 struct audit_context *audit_context; 1437 #ifdef CONFIG_AUDITSYSCALL 1438 uid_t loginuid; 1439 unsigned int sessionid; 1440 #endif 1441 seccomp_t seccomp; 1442 1443 /* Thread group tracking */ 1444 u32 parent_exec_id; 1445 u32 self_exec_id; 1446 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1447 * mempolicy */ 1448 spinlock_t alloc_lock; 1449 1450 /* Protection of the PI data structures: */ 1451 raw_spinlock_t pi_lock; 1452 1453 #ifdef CONFIG_RT_MUTEXES 1454 /* PI waiters blocked on a rt_mutex held by this task */ 1455 struct plist_head pi_waiters; 1456 /* Deadlock detection and priority inheritance handling */ 1457 struct rt_mutex_waiter *pi_blocked_on; 1458 #endif 1459 1460 #ifdef CONFIG_DEBUG_MUTEXES 1461 /* mutex deadlock detection */ 1462 struct mutex_waiter *blocked_on; 1463 #endif 1464 #ifdef CONFIG_TRACE_IRQFLAGS 1465 unsigned int irq_events; 1466 unsigned long hardirq_enable_ip; 1467 unsigned long hardirq_disable_ip; 1468 unsigned int hardirq_enable_event; 1469 unsigned int hardirq_disable_event; 1470 int hardirqs_enabled; 1471 int hardirq_context; 1472 unsigned long softirq_disable_ip; 1473 unsigned long softirq_enable_ip; 1474 unsigned int softirq_disable_event; 1475 unsigned int softirq_enable_event; 1476 int softirqs_enabled; 1477 int softirq_context; 1478 #endif 1479 #ifdef CONFIG_LOCKDEP 1480 # define MAX_LOCK_DEPTH 48UL 1481 u64 curr_chain_key; 1482 int lockdep_depth; 1483 unsigned int lockdep_recursion; 1484 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1485 gfp_t lockdep_reclaim_gfp; 1486 #endif 1487 1488 /* journalling filesystem info */ 1489 void *journal_info; 1490 1491 /* stacked block device info */ 1492 struct bio_list *bio_list; 1493 1494 #ifdef CONFIG_BLOCK 1495 /* stack plugging */ 1496 struct blk_plug *plug; 1497 #endif 1498 1499 /* VM state */ 1500 struct reclaim_state *reclaim_state; 1501 1502 struct backing_dev_info *backing_dev_info; 1503 1504 struct io_context *io_context; 1505 1506 unsigned long ptrace_message; 1507 siginfo_t *last_siginfo; /* For ptrace use. */ 1508 struct task_io_accounting ioac; 1509 #if defined(CONFIG_TASK_XACCT) 1510 u64 acct_rss_mem1; /* accumulated rss usage */ 1511 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1512 cputime_t acct_timexpd; /* stime + utime since last update */ 1513 #endif 1514 #ifdef CONFIG_CPUSETS 1515 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1516 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1517 int cpuset_mem_spread_rotor; 1518 int cpuset_slab_spread_rotor; 1519 #endif 1520 #ifdef CONFIG_CGROUPS 1521 /* Control Group info protected by css_set_lock */ 1522 struct css_set __rcu *cgroups; 1523 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1524 struct list_head cg_list; 1525 #endif 1526 #ifdef CONFIG_FUTEX 1527 struct robust_list_head __user *robust_list; 1528 #ifdef CONFIG_COMPAT 1529 struct compat_robust_list_head __user *compat_robust_list; 1530 #endif 1531 struct list_head pi_state_list; 1532 struct futex_pi_state *pi_state_cache; 1533 #endif 1534 #ifdef CONFIG_PERF_EVENTS 1535 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1536 struct mutex perf_event_mutex; 1537 struct list_head perf_event_list; 1538 #endif 1539 #ifdef CONFIG_NUMA 1540 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1541 short il_next; 1542 short pref_node_fork; 1543 #endif 1544 struct rcu_head rcu; 1545 1546 /* 1547 * cache last used pipe for splice 1548 */ 1549 struct pipe_inode_info *splice_pipe; 1550 #ifdef CONFIG_TASK_DELAY_ACCT 1551 struct task_delay_info *delays; 1552 #endif 1553 #ifdef CONFIG_FAULT_INJECTION 1554 int make_it_fail; 1555 #endif 1556 /* 1557 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1558 * balance_dirty_pages() for some dirty throttling pause 1559 */ 1560 int nr_dirtied; 1561 int nr_dirtied_pause; 1562 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1563 1564 #ifdef CONFIG_LATENCYTOP 1565 int latency_record_count; 1566 struct latency_record latency_record[LT_SAVECOUNT]; 1567 #endif 1568 /* 1569 * time slack values; these are used to round up poll() and 1570 * select() etc timeout values. These are in nanoseconds. 1571 */ 1572 unsigned long timer_slack_ns; 1573 unsigned long default_timer_slack_ns; 1574 1575 struct list_head *scm_work_list; 1576 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1577 /* Index of current stored address in ret_stack */ 1578 int curr_ret_stack; 1579 /* Stack of return addresses for return function tracing */ 1580 struct ftrace_ret_stack *ret_stack; 1581 /* time stamp for last schedule */ 1582 unsigned long long ftrace_timestamp; 1583 /* 1584 * Number of functions that haven't been traced 1585 * because of depth overrun. 1586 */ 1587 atomic_t trace_overrun; 1588 /* Pause for the tracing */ 1589 atomic_t tracing_graph_pause; 1590 #endif 1591 #ifdef CONFIG_TRACING 1592 /* state flags for use by tracers */ 1593 unsigned long trace; 1594 /* bitmask and counter of trace recursion */ 1595 unsigned long trace_recursion; 1596 #endif /* CONFIG_TRACING */ 1597 #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */ 1598 struct memcg_batch_info { 1599 int do_batch; /* incremented when batch uncharge started */ 1600 struct mem_cgroup *memcg; /* target memcg of uncharge */ 1601 unsigned long nr_pages; /* uncharged usage */ 1602 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ 1603 } memcg_batch; 1604 #endif 1605 #ifdef CONFIG_HAVE_HW_BREAKPOINT 1606 atomic_t ptrace_bp_refcnt; 1607 #endif 1608 }; 1609 1610 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1611 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1612 1613 /* 1614 * Priority of a process goes from 0..MAX_PRIO-1, valid RT 1615 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH 1616 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority 1617 * values are inverted: lower p->prio value means higher priority. 1618 * 1619 * The MAX_USER_RT_PRIO value allows the actual maximum 1620 * RT priority to be separate from the value exported to 1621 * user-space. This allows kernel threads to set their 1622 * priority to a value higher than any user task. Note: 1623 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO. 1624 */ 1625 1626 #define MAX_USER_RT_PRIO 100 1627 #define MAX_RT_PRIO MAX_USER_RT_PRIO 1628 1629 #define MAX_PRIO (MAX_RT_PRIO + 40) 1630 #define DEFAULT_PRIO (MAX_RT_PRIO + 20) 1631 1632 static inline int rt_prio(int prio) 1633 { 1634 if (unlikely(prio < MAX_RT_PRIO)) 1635 return 1; 1636 return 0; 1637 } 1638 1639 static inline int rt_task(struct task_struct *p) 1640 { 1641 return rt_prio(p->prio); 1642 } 1643 1644 static inline struct pid *task_pid(struct task_struct *task) 1645 { 1646 return task->pids[PIDTYPE_PID].pid; 1647 } 1648 1649 static inline struct pid *task_tgid(struct task_struct *task) 1650 { 1651 return task->group_leader->pids[PIDTYPE_PID].pid; 1652 } 1653 1654 /* 1655 * Without tasklist or rcu lock it is not safe to dereference 1656 * the result of task_pgrp/task_session even if task == current, 1657 * we can race with another thread doing sys_setsid/sys_setpgid. 1658 */ 1659 static inline struct pid *task_pgrp(struct task_struct *task) 1660 { 1661 return task->group_leader->pids[PIDTYPE_PGID].pid; 1662 } 1663 1664 static inline struct pid *task_session(struct task_struct *task) 1665 { 1666 return task->group_leader->pids[PIDTYPE_SID].pid; 1667 } 1668 1669 struct pid_namespace; 1670 1671 /* 1672 * the helpers to get the task's different pids as they are seen 1673 * from various namespaces 1674 * 1675 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1676 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1677 * current. 1678 * task_xid_nr_ns() : id seen from the ns specified; 1679 * 1680 * set_task_vxid() : assigns a virtual id to a task; 1681 * 1682 * see also pid_nr() etc in include/linux/pid.h 1683 */ 1684 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 1685 struct pid_namespace *ns); 1686 1687 static inline pid_t task_pid_nr(struct task_struct *tsk) 1688 { 1689 return tsk->pid; 1690 } 1691 1692 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 1693 struct pid_namespace *ns) 1694 { 1695 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1696 } 1697 1698 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1699 { 1700 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1701 } 1702 1703 1704 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1705 { 1706 return tsk->tgid; 1707 } 1708 1709 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 1710 1711 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1712 { 1713 return pid_vnr(task_tgid(tsk)); 1714 } 1715 1716 1717 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 1718 struct pid_namespace *ns) 1719 { 1720 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1721 } 1722 1723 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1724 { 1725 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1726 } 1727 1728 1729 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 1730 struct pid_namespace *ns) 1731 { 1732 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1733 } 1734 1735 static inline pid_t task_session_vnr(struct task_struct *tsk) 1736 { 1737 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1738 } 1739 1740 /* obsolete, do not use */ 1741 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1742 { 1743 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1744 } 1745 1746 /** 1747 * pid_alive - check that a task structure is not stale 1748 * @p: Task structure to be checked. 1749 * 1750 * Test if a process is not yet dead (at most zombie state) 1751 * If pid_alive fails, then pointers within the task structure 1752 * can be stale and must not be dereferenced. 1753 */ 1754 static inline int pid_alive(struct task_struct *p) 1755 { 1756 return p->pids[PIDTYPE_PID].pid != NULL; 1757 } 1758 1759 /** 1760 * is_global_init - check if a task structure is init 1761 * @tsk: Task structure to be checked. 1762 * 1763 * Check if a task structure is the first user space task the kernel created. 1764 */ 1765 static inline int is_global_init(struct task_struct *tsk) 1766 { 1767 return tsk->pid == 1; 1768 } 1769 1770 /* 1771 * is_container_init: 1772 * check whether in the task is init in its own pid namespace. 1773 */ 1774 extern int is_container_init(struct task_struct *tsk); 1775 1776 extern struct pid *cad_pid; 1777 1778 extern void free_task(struct task_struct *tsk); 1779 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 1780 1781 extern void __put_task_struct(struct task_struct *t); 1782 1783 static inline void put_task_struct(struct task_struct *t) 1784 { 1785 if (atomic_dec_and_test(&t->usage)) 1786 __put_task_struct(t); 1787 } 1788 1789 extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st); 1790 extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st); 1791 1792 /* 1793 * Per process flags 1794 */ 1795 #define PF_EXITING 0x00000004 /* getting shut down */ 1796 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 1797 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 1798 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1799 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 1800 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 1801 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 1802 #define PF_DUMPCORE 0x00000200 /* dumped core */ 1803 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 1804 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1805 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 1806 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 1807 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 1808 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 1809 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 1810 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 1811 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 1812 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1813 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 1814 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1815 #define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */ 1816 #define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */ 1817 #define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */ 1818 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1819 #define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */ 1820 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 1821 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1822 1823 /* 1824 * Only the _current_ task can read/write to tsk->flags, but other 1825 * tasks can access tsk->flags in readonly mode for example 1826 * with tsk_used_math (like during threaded core dumping). 1827 * There is however an exception to this rule during ptrace 1828 * or during fork: the ptracer task is allowed to write to the 1829 * child->flags of its traced child (same goes for fork, the parent 1830 * can write to the child->flags), because we're guaranteed the 1831 * child is not running and in turn not changing child->flags 1832 * at the same time the parent does it. 1833 */ 1834 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1835 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1836 #define clear_used_math() clear_stopped_child_used_math(current) 1837 #define set_used_math() set_stopped_child_used_math(current) 1838 #define conditional_stopped_child_used_math(condition, child) \ 1839 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1840 #define conditional_used_math(condition) \ 1841 conditional_stopped_child_used_math(condition, current) 1842 #define copy_to_stopped_child_used_math(child) \ 1843 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1844 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1845 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1846 #define used_math() tsk_used_math(current) 1847 1848 /* 1849 * task->jobctl flags 1850 */ 1851 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 1852 1853 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 1854 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 1855 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 1856 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 1857 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 1858 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 1859 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 1860 1861 #define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT) 1862 #define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT) 1863 #define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT) 1864 #define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT) 1865 #define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT) 1866 #define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT) 1867 #define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT) 1868 1869 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 1870 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 1871 1872 extern bool task_set_jobctl_pending(struct task_struct *task, 1873 unsigned int mask); 1874 extern void task_clear_jobctl_trapping(struct task_struct *task); 1875 extern void task_clear_jobctl_pending(struct task_struct *task, 1876 unsigned int mask); 1877 1878 #ifdef CONFIG_PREEMPT_RCU 1879 1880 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */ 1881 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */ 1882 1883 static inline void rcu_copy_process(struct task_struct *p) 1884 { 1885 p->rcu_read_lock_nesting = 0; 1886 p->rcu_read_unlock_special = 0; 1887 #ifdef CONFIG_TREE_PREEMPT_RCU 1888 p->rcu_blocked_node = NULL; 1889 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ 1890 #ifdef CONFIG_RCU_BOOST 1891 p->rcu_boost_mutex = NULL; 1892 #endif /* #ifdef CONFIG_RCU_BOOST */ 1893 INIT_LIST_HEAD(&p->rcu_node_entry); 1894 } 1895 1896 #else 1897 1898 static inline void rcu_copy_process(struct task_struct *p) 1899 { 1900 } 1901 1902 #endif 1903 1904 #ifdef CONFIG_SMP 1905 extern void do_set_cpus_allowed(struct task_struct *p, 1906 const struct cpumask *new_mask); 1907 1908 extern int set_cpus_allowed_ptr(struct task_struct *p, 1909 const struct cpumask *new_mask); 1910 #else 1911 static inline void do_set_cpus_allowed(struct task_struct *p, 1912 const struct cpumask *new_mask) 1913 { 1914 } 1915 static inline int set_cpus_allowed_ptr(struct task_struct *p, 1916 const struct cpumask *new_mask) 1917 { 1918 if (!cpumask_test_cpu(0, new_mask)) 1919 return -EINVAL; 1920 return 0; 1921 } 1922 #endif 1923 1924 #ifndef CONFIG_CPUMASK_OFFSTACK 1925 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) 1926 { 1927 return set_cpus_allowed_ptr(p, &new_mask); 1928 } 1929 #endif 1930 1931 /* 1932 * Do not use outside of architecture code which knows its limitations. 1933 * 1934 * sched_clock() has no promise of monotonicity or bounded drift between 1935 * CPUs, use (which you should not) requires disabling IRQs. 1936 * 1937 * Please use one of the three interfaces below. 1938 */ 1939 extern unsigned long long notrace sched_clock(void); 1940 /* 1941 * See the comment in kernel/sched_clock.c 1942 */ 1943 extern u64 cpu_clock(int cpu); 1944 extern u64 local_clock(void); 1945 extern u64 sched_clock_cpu(int cpu); 1946 1947 1948 extern void sched_clock_init(void); 1949 1950 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 1951 static inline void sched_clock_tick(void) 1952 { 1953 } 1954 1955 static inline void sched_clock_idle_sleep_event(void) 1956 { 1957 } 1958 1959 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 1960 { 1961 } 1962 #else 1963 /* 1964 * Architectures can set this to 1 if they have specified 1965 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 1966 * but then during bootup it turns out that sched_clock() 1967 * is reliable after all: 1968 */ 1969 extern int sched_clock_stable; 1970 1971 extern void sched_clock_tick(void); 1972 extern void sched_clock_idle_sleep_event(void); 1973 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 1974 #endif 1975 1976 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1977 /* 1978 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 1979 * The reason for this explicit opt-in is not to have perf penalty with 1980 * slow sched_clocks. 1981 */ 1982 extern void enable_sched_clock_irqtime(void); 1983 extern void disable_sched_clock_irqtime(void); 1984 #else 1985 static inline void enable_sched_clock_irqtime(void) {} 1986 static inline void disable_sched_clock_irqtime(void) {} 1987 #endif 1988 1989 extern unsigned long long 1990 task_sched_runtime(struct task_struct *task); 1991 1992 /* sched_exec is called by processes performing an exec */ 1993 #ifdef CONFIG_SMP 1994 extern void sched_exec(void); 1995 #else 1996 #define sched_exec() {} 1997 #endif 1998 1999 extern void sched_clock_idle_sleep_event(void); 2000 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2001 2002 #ifdef CONFIG_HOTPLUG_CPU 2003 extern void idle_task_exit(void); 2004 #else 2005 static inline void idle_task_exit(void) {} 2006 #endif 2007 2008 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP) 2009 extern void wake_up_idle_cpu(int cpu); 2010 #else 2011 static inline void wake_up_idle_cpu(int cpu) { } 2012 #endif 2013 2014 extern unsigned int sysctl_sched_latency; 2015 extern unsigned int sysctl_sched_min_granularity; 2016 extern unsigned int sysctl_sched_wakeup_granularity; 2017 extern unsigned int sysctl_sched_child_runs_first; 2018 2019 enum sched_tunable_scaling { 2020 SCHED_TUNABLESCALING_NONE, 2021 SCHED_TUNABLESCALING_LOG, 2022 SCHED_TUNABLESCALING_LINEAR, 2023 SCHED_TUNABLESCALING_END, 2024 }; 2025 extern enum sched_tunable_scaling sysctl_sched_tunable_scaling; 2026 2027 #ifdef CONFIG_SCHED_DEBUG 2028 extern unsigned int sysctl_sched_migration_cost; 2029 extern unsigned int sysctl_sched_nr_migrate; 2030 extern unsigned int sysctl_sched_time_avg; 2031 extern unsigned int sysctl_timer_migration; 2032 extern unsigned int sysctl_sched_shares_window; 2033 2034 int sched_proc_update_handler(struct ctl_table *table, int write, 2035 void __user *buffer, size_t *length, 2036 loff_t *ppos); 2037 #endif 2038 #ifdef CONFIG_SCHED_DEBUG 2039 static inline unsigned int get_sysctl_timer_migration(void) 2040 { 2041 return sysctl_timer_migration; 2042 } 2043 #else 2044 static inline unsigned int get_sysctl_timer_migration(void) 2045 { 2046 return 1; 2047 } 2048 #endif 2049 extern unsigned int sysctl_sched_rt_period; 2050 extern int sysctl_sched_rt_runtime; 2051 2052 int sched_rt_handler(struct ctl_table *table, int write, 2053 void __user *buffer, size_t *lenp, 2054 loff_t *ppos); 2055 2056 #ifdef CONFIG_SCHED_AUTOGROUP 2057 extern unsigned int sysctl_sched_autogroup_enabled; 2058 2059 extern void sched_autogroup_create_attach(struct task_struct *p); 2060 extern void sched_autogroup_detach(struct task_struct *p); 2061 extern void sched_autogroup_fork(struct signal_struct *sig); 2062 extern void sched_autogroup_exit(struct signal_struct *sig); 2063 #ifdef CONFIG_PROC_FS 2064 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2065 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2066 #endif 2067 #else 2068 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2069 static inline void sched_autogroup_detach(struct task_struct *p) { } 2070 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2071 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2072 #endif 2073 2074 #ifdef CONFIG_CFS_BANDWIDTH 2075 extern unsigned int sysctl_sched_cfs_bandwidth_slice; 2076 #endif 2077 2078 #ifdef CONFIG_RT_MUTEXES 2079 extern int rt_mutex_getprio(struct task_struct *p); 2080 extern void rt_mutex_setprio(struct task_struct *p, int prio); 2081 extern void rt_mutex_adjust_pi(struct task_struct *p); 2082 static inline bool tsk_is_pi_blocked(struct task_struct *tsk) 2083 { 2084 return tsk->pi_blocked_on != NULL; 2085 } 2086 #else 2087 static inline int rt_mutex_getprio(struct task_struct *p) 2088 { 2089 return p->normal_prio; 2090 } 2091 # define rt_mutex_adjust_pi(p) do { } while (0) 2092 static inline bool tsk_is_pi_blocked(struct task_struct *tsk) 2093 { 2094 return false; 2095 } 2096 #endif 2097 2098 extern bool yield_to(struct task_struct *p, bool preempt); 2099 extern void set_user_nice(struct task_struct *p, long nice); 2100 extern int task_prio(const struct task_struct *p); 2101 extern int task_nice(const struct task_struct *p); 2102 extern int can_nice(const struct task_struct *p, const int nice); 2103 extern int task_curr(const struct task_struct *p); 2104 extern int idle_cpu(int cpu); 2105 extern int sched_setscheduler(struct task_struct *, int, 2106 const struct sched_param *); 2107 extern int sched_setscheduler_nocheck(struct task_struct *, int, 2108 const struct sched_param *); 2109 extern struct task_struct *idle_task(int cpu); 2110 /** 2111 * is_idle_task - is the specified task an idle task? 2112 * @p: the task in question. 2113 */ 2114 static inline bool is_idle_task(const struct task_struct *p) 2115 { 2116 return p->pid == 0; 2117 } 2118 extern struct task_struct *curr_task(int cpu); 2119 extern void set_curr_task(int cpu, struct task_struct *p); 2120 2121 void yield(void); 2122 2123 /* 2124 * The default (Linux) execution domain. 2125 */ 2126 extern struct exec_domain default_exec_domain; 2127 2128 union thread_union { 2129 struct thread_info thread_info; 2130 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2131 }; 2132 2133 #ifndef __HAVE_ARCH_KSTACK_END 2134 static inline int kstack_end(void *addr) 2135 { 2136 /* Reliable end of stack detection: 2137 * Some APM bios versions misalign the stack 2138 */ 2139 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2140 } 2141 #endif 2142 2143 extern union thread_union init_thread_union; 2144 extern struct task_struct init_task; 2145 2146 extern struct mm_struct init_mm; 2147 2148 extern struct pid_namespace init_pid_ns; 2149 2150 /* 2151 * find a task by one of its numerical ids 2152 * 2153 * find_task_by_pid_ns(): 2154 * finds a task by its pid in the specified namespace 2155 * find_task_by_vpid(): 2156 * finds a task by its virtual pid 2157 * 2158 * see also find_vpid() etc in include/linux/pid.h 2159 */ 2160 2161 extern struct task_struct *find_task_by_vpid(pid_t nr); 2162 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2163 struct pid_namespace *ns); 2164 2165 extern void __set_special_pids(struct pid *pid); 2166 2167 /* per-UID process charging. */ 2168 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t); 2169 static inline struct user_struct *get_uid(struct user_struct *u) 2170 { 2171 atomic_inc(&u->__count); 2172 return u; 2173 } 2174 extern void free_uid(struct user_struct *); 2175 extern void release_uids(struct user_namespace *ns); 2176 2177 #include <asm/current.h> 2178 2179 extern void xtime_update(unsigned long ticks); 2180 2181 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2182 extern int wake_up_process(struct task_struct *tsk); 2183 extern void wake_up_new_task(struct task_struct *tsk); 2184 #ifdef CONFIG_SMP 2185 extern void kick_process(struct task_struct *tsk); 2186 #else 2187 static inline void kick_process(struct task_struct *tsk) { } 2188 #endif 2189 extern void sched_fork(struct task_struct *p); 2190 extern void sched_dead(struct task_struct *p); 2191 2192 extern void proc_caches_init(void); 2193 extern void flush_signals(struct task_struct *); 2194 extern void __flush_signals(struct task_struct *); 2195 extern void ignore_signals(struct task_struct *); 2196 extern void flush_signal_handlers(struct task_struct *, int force_default); 2197 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2198 2199 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) 2200 { 2201 unsigned long flags; 2202 int ret; 2203 2204 spin_lock_irqsave(&tsk->sighand->siglock, flags); 2205 ret = dequeue_signal(tsk, mask, info); 2206 spin_unlock_irqrestore(&tsk->sighand->siglock, flags); 2207 2208 return ret; 2209 } 2210 2211 extern void block_all_signals(int (*notifier)(void *priv), void *priv, 2212 sigset_t *mask); 2213 extern void unblock_all_signals(void); 2214 extern void release_task(struct task_struct * p); 2215 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2216 extern int force_sigsegv(int, struct task_struct *); 2217 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2218 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2219 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2220 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2221 const struct cred *, u32); 2222 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2223 extern int kill_pid(struct pid *pid, int sig, int priv); 2224 extern int kill_proc_info(int, struct siginfo *, pid_t); 2225 extern __must_check bool do_notify_parent(struct task_struct *, int); 2226 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2227 extern void force_sig(int, struct task_struct *); 2228 extern int send_sig(int, struct task_struct *, int); 2229 extern int zap_other_threads(struct task_struct *p); 2230 extern struct sigqueue *sigqueue_alloc(void); 2231 extern void sigqueue_free(struct sigqueue *); 2232 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2233 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2234 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long); 2235 2236 static inline int kill_cad_pid(int sig, int priv) 2237 { 2238 return kill_pid(cad_pid, sig, priv); 2239 } 2240 2241 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2242 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2243 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2244 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2245 2246 /* 2247 * True if we are on the alternate signal stack. 2248 */ 2249 static inline int on_sig_stack(unsigned long sp) 2250 { 2251 #ifdef CONFIG_STACK_GROWSUP 2252 return sp >= current->sas_ss_sp && 2253 sp - current->sas_ss_sp < current->sas_ss_size; 2254 #else 2255 return sp > current->sas_ss_sp && 2256 sp - current->sas_ss_sp <= current->sas_ss_size; 2257 #endif 2258 } 2259 2260 static inline int sas_ss_flags(unsigned long sp) 2261 { 2262 return (current->sas_ss_size == 0 ? SS_DISABLE 2263 : on_sig_stack(sp) ? SS_ONSTACK : 0); 2264 } 2265 2266 /* 2267 * Routines for handling mm_structs 2268 */ 2269 extern struct mm_struct * mm_alloc(void); 2270 2271 /* mmdrop drops the mm and the page tables */ 2272 extern void __mmdrop(struct mm_struct *); 2273 static inline void mmdrop(struct mm_struct * mm) 2274 { 2275 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2276 __mmdrop(mm); 2277 } 2278 2279 /* mmput gets rid of the mappings and all user-space */ 2280 extern void mmput(struct mm_struct *); 2281 /* Grab a reference to a task's mm, if it is not already going away */ 2282 extern struct mm_struct *get_task_mm(struct task_struct *task); 2283 /* 2284 * Grab a reference to a task's mm, if it is not already going away 2285 * and ptrace_may_access with the mode parameter passed to it 2286 * succeeds. 2287 */ 2288 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2289 /* Remove the current tasks stale references to the old mm_struct */ 2290 extern void mm_release(struct task_struct *, struct mm_struct *); 2291 /* Allocate a new mm structure and copy contents from tsk->mm */ 2292 extern struct mm_struct *dup_mm(struct task_struct *tsk); 2293 2294 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2295 struct task_struct *, struct pt_regs *); 2296 extern void flush_thread(void); 2297 extern void exit_thread(void); 2298 2299 extern void exit_files(struct task_struct *); 2300 extern void __cleanup_sighand(struct sighand_struct *); 2301 2302 extern void exit_itimers(struct signal_struct *); 2303 extern void flush_itimer_signals(void); 2304 2305 extern void do_group_exit(int); 2306 2307 extern void daemonize(const char *, ...); 2308 extern int allow_signal(int); 2309 extern int disallow_signal(int); 2310 2311 extern int do_execve(const char *, 2312 const char __user * const __user *, 2313 const char __user * const __user *, struct pt_regs *); 2314 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *); 2315 struct task_struct *fork_idle(int); 2316 2317 extern void set_task_comm(struct task_struct *tsk, char *from); 2318 extern char *get_task_comm(char *to, struct task_struct *tsk); 2319 2320 #ifdef CONFIG_SMP 2321 void scheduler_ipi(void); 2322 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2323 #else 2324 static inline void scheduler_ipi(void) { } 2325 static inline unsigned long wait_task_inactive(struct task_struct *p, 2326 long match_state) 2327 { 2328 return 1; 2329 } 2330 #endif 2331 2332 #define next_task(p) \ 2333 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2334 2335 #define for_each_process(p) \ 2336 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2337 2338 extern bool current_is_single_threaded(void); 2339 2340 /* 2341 * Careful: do_each_thread/while_each_thread is a double loop so 2342 * 'break' will not work as expected - use goto instead. 2343 */ 2344 #define do_each_thread(g, t) \ 2345 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2346 2347 #define while_each_thread(g, t) \ 2348 while ((t = next_thread(t)) != g) 2349 2350 static inline int get_nr_threads(struct task_struct *tsk) 2351 { 2352 return tsk->signal->nr_threads; 2353 } 2354 2355 static inline bool thread_group_leader(struct task_struct *p) 2356 { 2357 return p->exit_signal >= 0; 2358 } 2359 2360 /* Do to the insanities of de_thread it is possible for a process 2361 * to have the pid of the thread group leader without actually being 2362 * the thread group leader. For iteration through the pids in proc 2363 * all we care about is that we have a task with the appropriate 2364 * pid, we don't actually care if we have the right task. 2365 */ 2366 static inline int has_group_leader_pid(struct task_struct *p) 2367 { 2368 return p->pid == p->tgid; 2369 } 2370 2371 static inline 2372 int same_thread_group(struct task_struct *p1, struct task_struct *p2) 2373 { 2374 return p1->tgid == p2->tgid; 2375 } 2376 2377 static inline struct task_struct *next_thread(const struct task_struct *p) 2378 { 2379 return list_entry_rcu(p->thread_group.next, 2380 struct task_struct, thread_group); 2381 } 2382 2383 static inline int thread_group_empty(struct task_struct *p) 2384 { 2385 return list_empty(&p->thread_group); 2386 } 2387 2388 #define delay_group_leader(p) \ 2389 (thread_group_leader(p) && !thread_group_empty(p)) 2390 2391 /* 2392 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2393 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2394 * pins the final release of task.io_context. Also protects ->cpuset and 2395 * ->cgroup.subsys[]. And ->vfork_done. 2396 * 2397 * Nests both inside and outside of read_lock(&tasklist_lock). 2398 * It must not be nested with write_lock_irq(&tasklist_lock), 2399 * neither inside nor outside. 2400 */ 2401 static inline void task_lock(struct task_struct *p) 2402 { 2403 spin_lock(&p->alloc_lock); 2404 } 2405 2406 static inline void task_unlock(struct task_struct *p) 2407 { 2408 spin_unlock(&p->alloc_lock); 2409 } 2410 2411 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2412 unsigned long *flags); 2413 2414 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2415 unsigned long *flags) 2416 { 2417 struct sighand_struct *ret; 2418 2419 ret = __lock_task_sighand(tsk, flags); 2420 (void)__cond_lock(&tsk->sighand->siglock, ret); 2421 return ret; 2422 } 2423 2424 static inline void unlock_task_sighand(struct task_struct *tsk, 2425 unsigned long *flags) 2426 { 2427 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2428 } 2429 2430 #ifdef CONFIG_CGROUPS 2431 static inline void threadgroup_change_begin(struct task_struct *tsk) 2432 { 2433 down_read(&tsk->signal->group_rwsem); 2434 } 2435 static inline void threadgroup_change_end(struct task_struct *tsk) 2436 { 2437 up_read(&tsk->signal->group_rwsem); 2438 } 2439 2440 /** 2441 * threadgroup_lock - lock threadgroup 2442 * @tsk: member task of the threadgroup to lock 2443 * 2444 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter 2445 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or 2446 * perform exec. This is useful for cases where the threadgroup needs to 2447 * stay stable across blockable operations. 2448 * 2449 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for 2450 * synchronization. While held, no new task will be added to threadgroup 2451 * and no existing live task will have its PF_EXITING set. 2452 * 2453 * During exec, a task goes and puts its thread group through unusual 2454 * changes. After de-threading, exclusive access is assumed to resources 2455 * which are usually shared by tasks in the same group - e.g. sighand may 2456 * be replaced with a new one. Also, the exec'ing task takes over group 2457 * leader role including its pid. Exclude these changes while locked by 2458 * grabbing cred_guard_mutex which is used to synchronize exec path. 2459 */ 2460 static inline void threadgroup_lock(struct task_struct *tsk) 2461 { 2462 /* 2463 * exec uses exit for de-threading nesting group_rwsem inside 2464 * cred_guard_mutex. Grab cred_guard_mutex first. 2465 */ 2466 mutex_lock(&tsk->signal->cred_guard_mutex); 2467 down_write(&tsk->signal->group_rwsem); 2468 } 2469 2470 /** 2471 * threadgroup_unlock - unlock threadgroup 2472 * @tsk: member task of the threadgroup to unlock 2473 * 2474 * Reverse threadgroup_lock(). 2475 */ 2476 static inline void threadgroup_unlock(struct task_struct *tsk) 2477 { 2478 up_write(&tsk->signal->group_rwsem); 2479 mutex_unlock(&tsk->signal->cred_guard_mutex); 2480 } 2481 #else 2482 static inline void threadgroup_change_begin(struct task_struct *tsk) {} 2483 static inline void threadgroup_change_end(struct task_struct *tsk) {} 2484 static inline void threadgroup_lock(struct task_struct *tsk) {} 2485 static inline void threadgroup_unlock(struct task_struct *tsk) {} 2486 #endif 2487 2488 #ifndef __HAVE_THREAD_FUNCTIONS 2489 2490 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 2491 #define task_stack_page(task) ((task)->stack) 2492 2493 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2494 { 2495 *task_thread_info(p) = *task_thread_info(org); 2496 task_thread_info(p)->task = p; 2497 } 2498 2499 static inline unsigned long *end_of_stack(struct task_struct *p) 2500 { 2501 return (unsigned long *)(task_thread_info(p) + 1); 2502 } 2503 2504 #endif 2505 2506 static inline int object_is_on_stack(void *obj) 2507 { 2508 void *stack = task_stack_page(current); 2509 2510 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 2511 } 2512 2513 extern void thread_info_cache_init(void); 2514 2515 #ifdef CONFIG_DEBUG_STACK_USAGE 2516 static inline unsigned long stack_not_used(struct task_struct *p) 2517 { 2518 unsigned long *n = end_of_stack(p); 2519 2520 do { /* Skip over canary */ 2521 n++; 2522 } while (!*n); 2523 2524 return (unsigned long)n - (unsigned long)end_of_stack(p); 2525 } 2526 #endif 2527 2528 /* set thread flags in other task's structures 2529 * - see asm/thread_info.h for TIF_xxxx flags available 2530 */ 2531 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2532 { 2533 set_ti_thread_flag(task_thread_info(tsk), flag); 2534 } 2535 2536 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2537 { 2538 clear_ti_thread_flag(task_thread_info(tsk), flag); 2539 } 2540 2541 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2542 { 2543 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2544 } 2545 2546 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2547 { 2548 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2549 } 2550 2551 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2552 { 2553 return test_ti_thread_flag(task_thread_info(tsk), flag); 2554 } 2555 2556 static inline void set_tsk_need_resched(struct task_struct *tsk) 2557 { 2558 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2559 } 2560 2561 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2562 { 2563 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2564 } 2565 2566 static inline int test_tsk_need_resched(struct task_struct *tsk) 2567 { 2568 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2569 } 2570 2571 static inline int restart_syscall(void) 2572 { 2573 set_tsk_thread_flag(current, TIF_SIGPENDING); 2574 return -ERESTARTNOINTR; 2575 } 2576 2577 static inline int signal_pending(struct task_struct *p) 2578 { 2579 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 2580 } 2581 2582 static inline int __fatal_signal_pending(struct task_struct *p) 2583 { 2584 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 2585 } 2586 2587 static inline int fatal_signal_pending(struct task_struct *p) 2588 { 2589 return signal_pending(p) && __fatal_signal_pending(p); 2590 } 2591 2592 static inline int signal_pending_state(long state, struct task_struct *p) 2593 { 2594 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 2595 return 0; 2596 if (!signal_pending(p)) 2597 return 0; 2598 2599 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 2600 } 2601 2602 static inline int need_resched(void) 2603 { 2604 return unlikely(test_thread_flag(TIF_NEED_RESCHED)); 2605 } 2606 2607 /* 2608 * cond_resched() and cond_resched_lock(): latency reduction via 2609 * explicit rescheduling in places that are safe. The return 2610 * value indicates whether a reschedule was done in fact. 2611 * cond_resched_lock() will drop the spinlock before scheduling, 2612 * cond_resched_softirq() will enable bhs before scheduling. 2613 */ 2614 extern int _cond_resched(void); 2615 2616 #define cond_resched() ({ \ 2617 __might_sleep(__FILE__, __LINE__, 0); \ 2618 _cond_resched(); \ 2619 }) 2620 2621 extern int __cond_resched_lock(spinlock_t *lock); 2622 2623 #ifdef CONFIG_PREEMPT_COUNT 2624 #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET 2625 #else 2626 #define PREEMPT_LOCK_OFFSET 0 2627 #endif 2628 2629 #define cond_resched_lock(lock) ({ \ 2630 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2631 __cond_resched_lock(lock); \ 2632 }) 2633 2634 extern int __cond_resched_softirq(void); 2635 2636 #define cond_resched_softirq() ({ \ 2637 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 2638 __cond_resched_softirq(); \ 2639 }) 2640 2641 /* 2642 * Does a critical section need to be broken due to another 2643 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 2644 * but a general need for low latency) 2645 */ 2646 static inline int spin_needbreak(spinlock_t *lock) 2647 { 2648 #ifdef CONFIG_PREEMPT 2649 return spin_is_contended(lock); 2650 #else 2651 return 0; 2652 #endif 2653 } 2654 2655 /* 2656 * Thread group CPU time accounting. 2657 */ 2658 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 2659 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 2660 2661 static inline void thread_group_cputime_init(struct signal_struct *sig) 2662 { 2663 raw_spin_lock_init(&sig->cputimer.lock); 2664 } 2665 2666 /* 2667 * Reevaluate whether the task has signals pending delivery. 2668 * Wake the task if so. 2669 * This is required every time the blocked sigset_t changes. 2670 * callers must hold sighand->siglock. 2671 */ 2672 extern void recalc_sigpending_and_wake(struct task_struct *t); 2673 extern void recalc_sigpending(void); 2674 2675 extern void signal_wake_up(struct task_struct *t, int resume_stopped); 2676 2677 /* 2678 * Wrappers for p->thread_info->cpu access. No-op on UP. 2679 */ 2680 #ifdef CONFIG_SMP 2681 2682 static inline unsigned int task_cpu(const struct task_struct *p) 2683 { 2684 return task_thread_info(p)->cpu; 2685 } 2686 2687 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2688 2689 #else 2690 2691 static inline unsigned int task_cpu(const struct task_struct *p) 2692 { 2693 return 0; 2694 } 2695 2696 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2697 { 2698 } 2699 2700 #endif /* CONFIG_SMP */ 2701 2702 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2703 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2704 2705 extern void normalize_rt_tasks(void); 2706 2707 #ifdef CONFIG_CGROUP_SCHED 2708 2709 extern struct task_group root_task_group; 2710 2711 extern struct task_group *sched_create_group(struct task_group *parent); 2712 extern void sched_destroy_group(struct task_group *tg); 2713 extern void sched_move_task(struct task_struct *tsk); 2714 #ifdef CONFIG_FAIR_GROUP_SCHED 2715 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 2716 extern unsigned long sched_group_shares(struct task_group *tg); 2717 #endif 2718 #ifdef CONFIG_RT_GROUP_SCHED 2719 extern int sched_group_set_rt_runtime(struct task_group *tg, 2720 long rt_runtime_us); 2721 extern long sched_group_rt_runtime(struct task_group *tg); 2722 extern int sched_group_set_rt_period(struct task_group *tg, 2723 long rt_period_us); 2724 extern long sched_group_rt_period(struct task_group *tg); 2725 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 2726 #endif 2727 #endif 2728 2729 extern int task_can_switch_user(struct user_struct *up, 2730 struct task_struct *tsk); 2731 2732 #ifdef CONFIG_TASK_XACCT 2733 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2734 { 2735 tsk->ioac.rchar += amt; 2736 } 2737 2738 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2739 { 2740 tsk->ioac.wchar += amt; 2741 } 2742 2743 static inline void inc_syscr(struct task_struct *tsk) 2744 { 2745 tsk->ioac.syscr++; 2746 } 2747 2748 static inline void inc_syscw(struct task_struct *tsk) 2749 { 2750 tsk->ioac.syscw++; 2751 } 2752 #else 2753 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 2754 { 2755 } 2756 2757 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 2758 { 2759 } 2760 2761 static inline void inc_syscr(struct task_struct *tsk) 2762 { 2763 } 2764 2765 static inline void inc_syscw(struct task_struct *tsk) 2766 { 2767 } 2768 #endif 2769 2770 #ifndef TASK_SIZE_OF 2771 #define TASK_SIZE_OF(tsk) TASK_SIZE 2772 #endif 2773 2774 #ifdef CONFIG_MM_OWNER 2775 extern void mm_update_next_owner(struct mm_struct *mm); 2776 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p); 2777 #else 2778 static inline void mm_update_next_owner(struct mm_struct *mm) 2779 { 2780 } 2781 2782 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p) 2783 { 2784 } 2785 #endif /* CONFIG_MM_OWNER */ 2786 2787 static inline unsigned long task_rlimit(const struct task_struct *tsk, 2788 unsigned int limit) 2789 { 2790 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur); 2791 } 2792 2793 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 2794 unsigned int limit) 2795 { 2796 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max); 2797 } 2798 2799 static inline unsigned long rlimit(unsigned int limit) 2800 { 2801 return task_rlimit(current, limit); 2802 } 2803 2804 static inline unsigned long rlimit_max(unsigned int limit) 2805 { 2806 return task_rlimit_max(current, limit); 2807 } 2808 2809 #endif /* __KERNEL__ */ 2810 2811 #endif 2812