1 #ifndef _LINUX_SCHED_H 2 #define _LINUX_SCHED_H 3 4 #include <uapi/linux/sched.h> 5 6 #include <linux/sched/prio.h> 7 8 9 struct sched_param { 10 int sched_priority; 11 }; 12 13 #include <asm/param.h> /* for HZ */ 14 15 #include <linux/capability.h> 16 #include <linux/threads.h> 17 #include <linux/kernel.h> 18 #include <linux/types.h> 19 #include <linux/timex.h> 20 #include <linux/jiffies.h> 21 #include <linux/plist.h> 22 #include <linux/rbtree.h> 23 #include <linux/thread_info.h> 24 #include <linux/cpumask.h> 25 #include <linux/errno.h> 26 #include <linux/nodemask.h> 27 #include <linux/mm_types.h> 28 #include <linux/preempt.h> 29 30 #include <asm/page.h> 31 #include <asm/ptrace.h> 32 #include <linux/cputime.h> 33 34 #include <linux/smp.h> 35 #include <linux/sem.h> 36 #include <linux/shm.h> 37 #include <linux/signal.h> 38 #include <linux/compiler.h> 39 #include <linux/completion.h> 40 #include <linux/pid.h> 41 #include <linux/percpu.h> 42 #include <linux/topology.h> 43 #include <linux/seccomp.h> 44 #include <linux/rcupdate.h> 45 #include <linux/rculist.h> 46 #include <linux/rtmutex.h> 47 48 #include <linux/time.h> 49 #include <linux/param.h> 50 #include <linux/resource.h> 51 #include <linux/timer.h> 52 #include <linux/hrtimer.h> 53 #include <linux/kcov.h> 54 #include <linux/task_io_accounting.h> 55 #include <linux/latencytop.h> 56 #include <linux/cred.h> 57 #include <linux/llist.h> 58 #include <linux/uidgid.h> 59 #include <linux/gfp.h> 60 #include <linux/magic.h> 61 #include <linux/cgroup-defs.h> 62 63 #include <asm/processor.h> 64 65 #define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */ 66 67 /* 68 * Extended scheduling parameters data structure. 69 * 70 * This is needed because the original struct sched_param can not be 71 * altered without introducing ABI issues with legacy applications 72 * (e.g., in sched_getparam()). 73 * 74 * However, the possibility of specifying more than just a priority for 75 * the tasks may be useful for a wide variety of application fields, e.g., 76 * multimedia, streaming, automation and control, and many others. 77 * 78 * This variant (sched_attr) is meant at describing a so-called 79 * sporadic time-constrained task. In such model a task is specified by: 80 * - the activation period or minimum instance inter-arrival time; 81 * - the maximum (or average, depending on the actual scheduling 82 * discipline) computation time of all instances, a.k.a. runtime; 83 * - the deadline (relative to the actual activation time) of each 84 * instance. 85 * Very briefly, a periodic (sporadic) task asks for the execution of 86 * some specific computation --which is typically called an instance-- 87 * (at most) every period. Moreover, each instance typically lasts no more 88 * than the runtime and must be completed by time instant t equal to 89 * the instance activation time + the deadline. 90 * 91 * This is reflected by the actual fields of the sched_attr structure: 92 * 93 * @size size of the structure, for fwd/bwd compat. 94 * 95 * @sched_policy task's scheduling policy 96 * @sched_flags for customizing the scheduler behaviour 97 * @sched_nice task's nice value (SCHED_NORMAL/BATCH) 98 * @sched_priority task's static priority (SCHED_FIFO/RR) 99 * @sched_deadline representative of the task's deadline 100 * @sched_runtime representative of the task's runtime 101 * @sched_period representative of the task's period 102 * 103 * Given this task model, there are a multiplicity of scheduling algorithms 104 * and policies, that can be used to ensure all the tasks will make their 105 * timing constraints. 106 * 107 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the 108 * only user of this new interface. More information about the algorithm 109 * available in the scheduling class file or in Documentation/. 110 */ 111 struct sched_attr { 112 u32 size; 113 114 u32 sched_policy; 115 u64 sched_flags; 116 117 /* SCHED_NORMAL, SCHED_BATCH */ 118 s32 sched_nice; 119 120 /* SCHED_FIFO, SCHED_RR */ 121 u32 sched_priority; 122 123 /* SCHED_DEADLINE */ 124 u64 sched_runtime; 125 u64 sched_deadline; 126 u64 sched_period; 127 }; 128 129 struct futex_pi_state; 130 struct robust_list_head; 131 struct bio_list; 132 struct fs_struct; 133 struct perf_event_context; 134 struct blk_plug; 135 struct filename; 136 struct nameidata; 137 138 #define VMACACHE_BITS 2 139 #define VMACACHE_SIZE (1U << VMACACHE_BITS) 140 #define VMACACHE_MASK (VMACACHE_SIZE - 1) 141 142 /* 143 * These are the constant used to fake the fixed-point load-average 144 * counting. Some notes: 145 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 146 * a load-average precision of 10 bits integer + 11 bits fractional 147 * - if you want to count load-averages more often, you need more 148 * precision, or rounding will get you. With 2-second counting freq, 149 * the EXP_n values would be 1981, 2034 and 2043 if still using only 150 * 11 bit fractions. 151 */ 152 extern unsigned long avenrun[]; /* Load averages */ 153 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 154 155 #define FSHIFT 11 /* nr of bits of precision */ 156 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 157 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 158 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 159 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 160 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 161 162 #define CALC_LOAD(load,exp,n) \ 163 load *= exp; \ 164 load += n*(FIXED_1-exp); \ 165 load >>= FSHIFT; 166 167 extern unsigned long total_forks; 168 extern int nr_threads; 169 DECLARE_PER_CPU(unsigned long, process_counts); 170 extern int nr_processes(void); 171 extern unsigned long nr_running(void); 172 extern bool single_task_running(void); 173 extern unsigned long nr_iowait(void); 174 extern unsigned long nr_iowait_cpu(int cpu); 175 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load); 176 177 extern void calc_global_load(unsigned long ticks); 178 179 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 180 extern void cpu_load_update_nohz_start(void); 181 extern void cpu_load_update_nohz_stop(void); 182 #else 183 static inline void cpu_load_update_nohz_start(void) { } 184 static inline void cpu_load_update_nohz_stop(void) { } 185 #endif 186 187 extern void dump_cpu_task(int cpu); 188 189 struct seq_file; 190 struct cfs_rq; 191 struct task_group; 192 #ifdef CONFIG_SCHED_DEBUG 193 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 194 extern void proc_sched_set_task(struct task_struct *p); 195 #endif 196 197 /* 198 * Task state bitmask. NOTE! These bits are also 199 * encoded in fs/proc/array.c: get_task_state(). 200 * 201 * We have two separate sets of flags: task->state 202 * is about runnability, while task->exit_state are 203 * about the task exiting. Confusing, but this way 204 * modifying one set can't modify the other one by 205 * mistake. 206 */ 207 #define TASK_RUNNING 0 208 #define TASK_INTERRUPTIBLE 1 209 #define TASK_UNINTERRUPTIBLE 2 210 #define __TASK_STOPPED 4 211 #define __TASK_TRACED 8 212 /* in tsk->exit_state */ 213 #define EXIT_DEAD 16 214 #define EXIT_ZOMBIE 32 215 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 216 /* in tsk->state again */ 217 #define TASK_DEAD 64 218 #define TASK_WAKEKILL 128 219 #define TASK_WAKING 256 220 #define TASK_PARKED 512 221 #define TASK_NOLOAD 1024 222 #define TASK_STATE_MAX 2048 223 224 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN" 225 226 extern char ___assert_task_state[1 - 2*!!( 227 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 228 229 /* Convenience macros for the sake of set_task_state */ 230 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 231 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 232 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 233 234 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 235 236 /* Convenience macros for the sake of wake_up */ 237 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 238 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 239 240 /* get_task_state() */ 241 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 242 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 243 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD) 244 245 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 246 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 247 #define task_is_stopped_or_traced(task) \ 248 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 249 #define task_contributes_to_load(task) \ 250 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 251 (task->flags & PF_FROZEN) == 0 && \ 252 (task->state & TASK_NOLOAD) == 0) 253 254 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 255 256 #define __set_task_state(tsk, state_value) \ 257 do { \ 258 (tsk)->task_state_change = _THIS_IP_; \ 259 (tsk)->state = (state_value); \ 260 } while (0) 261 #define set_task_state(tsk, state_value) \ 262 do { \ 263 (tsk)->task_state_change = _THIS_IP_; \ 264 smp_store_mb((tsk)->state, (state_value)); \ 265 } while (0) 266 267 /* 268 * set_current_state() includes a barrier so that the write of current->state 269 * is correctly serialised wrt the caller's subsequent test of whether to 270 * actually sleep: 271 * 272 * set_current_state(TASK_UNINTERRUPTIBLE); 273 * if (do_i_need_to_sleep()) 274 * schedule(); 275 * 276 * If the caller does not need such serialisation then use __set_current_state() 277 */ 278 #define __set_current_state(state_value) \ 279 do { \ 280 current->task_state_change = _THIS_IP_; \ 281 current->state = (state_value); \ 282 } while (0) 283 #define set_current_state(state_value) \ 284 do { \ 285 current->task_state_change = _THIS_IP_; \ 286 smp_store_mb(current->state, (state_value)); \ 287 } while (0) 288 289 #else 290 291 #define __set_task_state(tsk, state_value) \ 292 do { (tsk)->state = (state_value); } while (0) 293 #define set_task_state(tsk, state_value) \ 294 smp_store_mb((tsk)->state, (state_value)) 295 296 /* 297 * set_current_state() includes a barrier so that the write of current->state 298 * is correctly serialised wrt the caller's subsequent test of whether to 299 * actually sleep: 300 * 301 * set_current_state(TASK_UNINTERRUPTIBLE); 302 * if (do_i_need_to_sleep()) 303 * schedule(); 304 * 305 * If the caller does not need such serialisation then use __set_current_state() 306 */ 307 #define __set_current_state(state_value) \ 308 do { current->state = (state_value); } while (0) 309 #define set_current_state(state_value) \ 310 smp_store_mb(current->state, (state_value)) 311 312 #endif 313 314 /* Task command name length */ 315 #define TASK_COMM_LEN 16 316 317 #include <linux/spinlock.h> 318 319 /* 320 * This serializes "schedule()" and also protects 321 * the run-queue from deletions/modifications (but 322 * _adding_ to the beginning of the run-queue has 323 * a separate lock). 324 */ 325 extern rwlock_t tasklist_lock; 326 extern spinlock_t mmlist_lock; 327 328 struct task_struct; 329 330 #ifdef CONFIG_PROVE_RCU 331 extern int lockdep_tasklist_lock_is_held(void); 332 #endif /* #ifdef CONFIG_PROVE_RCU */ 333 334 extern void sched_init(void); 335 extern void sched_init_smp(void); 336 extern asmlinkage void schedule_tail(struct task_struct *prev); 337 extern void init_idle(struct task_struct *idle, int cpu); 338 extern void init_idle_bootup_task(struct task_struct *idle); 339 340 extern cpumask_var_t cpu_isolated_map; 341 342 extern int runqueue_is_locked(int cpu); 343 344 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 345 extern void nohz_balance_enter_idle(int cpu); 346 extern void set_cpu_sd_state_idle(void); 347 extern int get_nohz_timer_target(void); 348 #else 349 static inline void nohz_balance_enter_idle(int cpu) { } 350 static inline void set_cpu_sd_state_idle(void) { } 351 #endif 352 353 /* 354 * Only dump TASK_* tasks. (0 for all tasks) 355 */ 356 extern void show_state_filter(unsigned long state_filter); 357 358 static inline void show_state(void) 359 { 360 show_state_filter(0); 361 } 362 363 extern void show_regs(struct pt_regs *); 364 365 /* 366 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 367 * task), SP is the stack pointer of the first frame that should be shown in the back 368 * trace (or NULL if the entire call-chain of the task should be shown). 369 */ 370 extern void show_stack(struct task_struct *task, unsigned long *sp); 371 372 extern void cpu_init (void); 373 extern void trap_init(void); 374 extern void update_process_times(int user); 375 extern void scheduler_tick(void); 376 extern int sched_cpu_starting(unsigned int cpu); 377 extern int sched_cpu_activate(unsigned int cpu); 378 extern int sched_cpu_deactivate(unsigned int cpu); 379 380 #ifdef CONFIG_HOTPLUG_CPU 381 extern int sched_cpu_dying(unsigned int cpu); 382 #else 383 # define sched_cpu_dying NULL 384 #endif 385 386 extern void sched_show_task(struct task_struct *p); 387 388 #ifdef CONFIG_LOCKUP_DETECTOR 389 extern void touch_softlockup_watchdog_sched(void); 390 extern void touch_softlockup_watchdog(void); 391 extern void touch_softlockup_watchdog_sync(void); 392 extern void touch_all_softlockup_watchdogs(void); 393 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 394 void __user *buffer, 395 size_t *lenp, loff_t *ppos); 396 extern unsigned int softlockup_panic; 397 extern unsigned int hardlockup_panic; 398 void lockup_detector_init(void); 399 #else 400 static inline void touch_softlockup_watchdog_sched(void) 401 { 402 } 403 static inline void touch_softlockup_watchdog(void) 404 { 405 } 406 static inline void touch_softlockup_watchdog_sync(void) 407 { 408 } 409 static inline void touch_all_softlockup_watchdogs(void) 410 { 411 } 412 static inline void lockup_detector_init(void) 413 { 414 } 415 #endif 416 417 #ifdef CONFIG_DETECT_HUNG_TASK 418 void reset_hung_task_detector(void); 419 #else 420 static inline void reset_hung_task_detector(void) 421 { 422 } 423 #endif 424 425 /* Attach to any functions which should be ignored in wchan output. */ 426 #define __sched __attribute__((__section__(".sched.text"))) 427 428 /* Linker adds these: start and end of __sched functions */ 429 extern char __sched_text_start[], __sched_text_end[]; 430 431 /* Is this address in the __sched functions? */ 432 extern int in_sched_functions(unsigned long addr); 433 434 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 435 extern signed long schedule_timeout(signed long timeout); 436 extern signed long schedule_timeout_interruptible(signed long timeout); 437 extern signed long schedule_timeout_killable(signed long timeout); 438 extern signed long schedule_timeout_uninterruptible(signed long timeout); 439 extern signed long schedule_timeout_idle(signed long timeout); 440 asmlinkage void schedule(void); 441 extern void schedule_preempt_disabled(void); 442 443 extern long io_schedule_timeout(long timeout); 444 445 static inline void io_schedule(void) 446 { 447 io_schedule_timeout(MAX_SCHEDULE_TIMEOUT); 448 } 449 450 struct nsproxy; 451 struct user_namespace; 452 453 #ifdef CONFIG_MMU 454 extern void arch_pick_mmap_layout(struct mm_struct *mm); 455 extern unsigned long 456 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 457 unsigned long, unsigned long); 458 extern unsigned long 459 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 460 unsigned long len, unsigned long pgoff, 461 unsigned long flags); 462 #else 463 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 464 #endif 465 466 #define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 467 #define SUID_DUMP_USER 1 /* Dump as user of process */ 468 #define SUID_DUMP_ROOT 2 /* Dump as root */ 469 470 /* mm flags */ 471 472 /* for SUID_DUMP_* above */ 473 #define MMF_DUMPABLE_BITS 2 474 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 475 476 extern void set_dumpable(struct mm_struct *mm, int value); 477 /* 478 * This returns the actual value of the suid_dumpable flag. For things 479 * that are using this for checking for privilege transitions, it must 480 * test against SUID_DUMP_USER rather than treating it as a boolean 481 * value. 482 */ 483 static inline int __get_dumpable(unsigned long mm_flags) 484 { 485 return mm_flags & MMF_DUMPABLE_MASK; 486 } 487 488 static inline int get_dumpable(struct mm_struct *mm) 489 { 490 return __get_dumpable(mm->flags); 491 } 492 493 /* coredump filter bits */ 494 #define MMF_DUMP_ANON_PRIVATE 2 495 #define MMF_DUMP_ANON_SHARED 3 496 #define MMF_DUMP_MAPPED_PRIVATE 4 497 #define MMF_DUMP_MAPPED_SHARED 5 498 #define MMF_DUMP_ELF_HEADERS 6 499 #define MMF_DUMP_HUGETLB_PRIVATE 7 500 #define MMF_DUMP_HUGETLB_SHARED 8 501 #define MMF_DUMP_DAX_PRIVATE 9 502 #define MMF_DUMP_DAX_SHARED 10 503 504 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 505 #define MMF_DUMP_FILTER_BITS 9 506 #define MMF_DUMP_FILTER_MASK \ 507 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 508 #define MMF_DUMP_FILTER_DEFAULT \ 509 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 510 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 511 512 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 513 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 514 #else 515 # define MMF_DUMP_MASK_DEFAULT_ELF 0 516 #endif 517 /* leave room for more dump flags */ 518 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 519 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 520 #define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 521 522 #define MMF_HAS_UPROBES 19 /* has uprobes */ 523 #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 524 #define MMF_OOM_REAPED 21 /* mm has been already reaped */ 525 526 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 527 528 struct sighand_struct { 529 atomic_t count; 530 struct k_sigaction action[_NSIG]; 531 spinlock_t siglock; 532 wait_queue_head_t signalfd_wqh; 533 }; 534 535 struct pacct_struct { 536 int ac_flag; 537 long ac_exitcode; 538 unsigned long ac_mem; 539 cputime_t ac_utime, ac_stime; 540 unsigned long ac_minflt, ac_majflt; 541 }; 542 543 struct cpu_itimer { 544 cputime_t expires; 545 cputime_t incr; 546 u32 error; 547 u32 incr_error; 548 }; 549 550 /** 551 * struct prev_cputime - snaphsot of system and user cputime 552 * @utime: time spent in user mode 553 * @stime: time spent in system mode 554 * @lock: protects the above two fields 555 * 556 * Stores previous user/system time values such that we can guarantee 557 * monotonicity. 558 */ 559 struct prev_cputime { 560 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 561 cputime_t utime; 562 cputime_t stime; 563 raw_spinlock_t lock; 564 #endif 565 }; 566 567 static inline void prev_cputime_init(struct prev_cputime *prev) 568 { 569 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 570 prev->utime = prev->stime = 0; 571 raw_spin_lock_init(&prev->lock); 572 #endif 573 } 574 575 /** 576 * struct task_cputime - collected CPU time counts 577 * @utime: time spent in user mode, in &cputime_t units 578 * @stime: time spent in kernel mode, in &cputime_t units 579 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 580 * 581 * This structure groups together three kinds of CPU time that are tracked for 582 * threads and thread groups. Most things considering CPU time want to group 583 * these counts together and treat all three of them in parallel. 584 */ 585 struct task_cputime { 586 cputime_t utime; 587 cputime_t stime; 588 unsigned long long sum_exec_runtime; 589 }; 590 591 /* Alternate field names when used to cache expirations. */ 592 #define virt_exp utime 593 #define prof_exp stime 594 #define sched_exp sum_exec_runtime 595 596 #define INIT_CPUTIME \ 597 (struct task_cputime) { \ 598 .utime = 0, \ 599 .stime = 0, \ 600 .sum_exec_runtime = 0, \ 601 } 602 603 /* 604 * This is the atomic variant of task_cputime, which can be used for 605 * storing and updating task_cputime statistics without locking. 606 */ 607 struct task_cputime_atomic { 608 atomic64_t utime; 609 atomic64_t stime; 610 atomic64_t sum_exec_runtime; 611 }; 612 613 #define INIT_CPUTIME_ATOMIC \ 614 (struct task_cputime_atomic) { \ 615 .utime = ATOMIC64_INIT(0), \ 616 .stime = ATOMIC64_INIT(0), \ 617 .sum_exec_runtime = ATOMIC64_INIT(0), \ 618 } 619 620 #define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) 621 622 /* 623 * Disable preemption until the scheduler is running -- use an unconditional 624 * value so that it also works on !PREEMPT_COUNT kernels. 625 * 626 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count(). 627 */ 628 #define INIT_PREEMPT_COUNT PREEMPT_OFFSET 629 630 /* 631 * Initial preempt_count value; reflects the preempt_count schedule invariant 632 * which states that during context switches: 633 * 634 * preempt_count() == 2*PREEMPT_DISABLE_OFFSET 635 * 636 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels. 637 * Note: See finish_task_switch(). 638 */ 639 #define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) 640 641 /** 642 * struct thread_group_cputimer - thread group interval timer counts 643 * @cputime_atomic: atomic thread group interval timers. 644 * @running: true when there are timers running and 645 * @cputime_atomic receives updates. 646 * @checking_timer: true when a thread in the group is in the 647 * process of checking for thread group timers. 648 * 649 * This structure contains the version of task_cputime, above, that is 650 * used for thread group CPU timer calculations. 651 */ 652 struct thread_group_cputimer { 653 struct task_cputime_atomic cputime_atomic; 654 bool running; 655 bool checking_timer; 656 }; 657 658 #include <linux/rwsem.h> 659 struct autogroup; 660 661 /* 662 * NOTE! "signal_struct" does not have its own 663 * locking, because a shared signal_struct always 664 * implies a shared sighand_struct, so locking 665 * sighand_struct is always a proper superset of 666 * the locking of signal_struct. 667 */ 668 struct signal_struct { 669 atomic_t sigcnt; 670 atomic_t live; 671 int nr_threads; 672 atomic_t oom_victims; /* # of TIF_MEDIE threads in this thread group */ 673 struct list_head thread_head; 674 675 wait_queue_head_t wait_chldexit; /* for wait4() */ 676 677 /* current thread group signal load-balancing target: */ 678 struct task_struct *curr_target; 679 680 /* shared signal handling: */ 681 struct sigpending shared_pending; 682 683 /* thread group exit support */ 684 int group_exit_code; 685 /* overloaded: 686 * - notify group_exit_task when ->count is equal to notify_count 687 * - everyone except group_exit_task is stopped during signal delivery 688 * of fatal signals, group_exit_task processes the signal. 689 */ 690 int notify_count; 691 struct task_struct *group_exit_task; 692 693 /* thread group stop support, overloads group_exit_code too */ 694 int group_stop_count; 695 unsigned int flags; /* see SIGNAL_* flags below */ 696 697 /* 698 * PR_SET_CHILD_SUBREAPER marks a process, like a service 699 * manager, to re-parent orphan (double-forking) child processes 700 * to this process instead of 'init'. The service manager is 701 * able to receive SIGCHLD signals and is able to investigate 702 * the process until it calls wait(). All children of this 703 * process will inherit a flag if they should look for a 704 * child_subreaper process at exit. 705 */ 706 unsigned int is_child_subreaper:1; 707 unsigned int has_child_subreaper:1; 708 709 /* POSIX.1b Interval Timers */ 710 int posix_timer_id; 711 struct list_head posix_timers; 712 713 /* ITIMER_REAL timer for the process */ 714 struct hrtimer real_timer; 715 struct pid *leader_pid; 716 ktime_t it_real_incr; 717 718 /* 719 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 720 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 721 * values are defined to 0 and 1 respectively 722 */ 723 struct cpu_itimer it[2]; 724 725 /* 726 * Thread group totals for process CPU timers. 727 * See thread_group_cputimer(), et al, for details. 728 */ 729 struct thread_group_cputimer cputimer; 730 731 /* Earliest-expiration cache. */ 732 struct task_cputime cputime_expires; 733 734 #ifdef CONFIG_NO_HZ_FULL 735 atomic_t tick_dep_mask; 736 #endif 737 738 struct list_head cpu_timers[3]; 739 740 struct pid *tty_old_pgrp; 741 742 /* boolean value for session group leader */ 743 int leader; 744 745 struct tty_struct *tty; /* NULL if no tty */ 746 747 #ifdef CONFIG_SCHED_AUTOGROUP 748 struct autogroup *autogroup; 749 #endif 750 /* 751 * Cumulative resource counters for dead threads in the group, 752 * and for reaped dead child processes forked by this group. 753 * Live threads maintain their own counters and add to these 754 * in __exit_signal, except for the group leader. 755 */ 756 seqlock_t stats_lock; 757 cputime_t utime, stime, cutime, cstime; 758 cputime_t gtime; 759 cputime_t cgtime; 760 struct prev_cputime prev_cputime; 761 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 762 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 763 unsigned long inblock, oublock, cinblock, coublock; 764 unsigned long maxrss, cmaxrss; 765 struct task_io_accounting ioac; 766 767 /* 768 * Cumulative ns of schedule CPU time fo dead threads in the 769 * group, not including a zombie group leader, (This only differs 770 * from jiffies_to_ns(utime + stime) if sched_clock uses something 771 * other than jiffies.) 772 */ 773 unsigned long long sum_sched_runtime; 774 775 /* 776 * We don't bother to synchronize most readers of this at all, 777 * because there is no reader checking a limit that actually needs 778 * to get both rlim_cur and rlim_max atomically, and either one 779 * alone is a single word that can safely be read normally. 780 * getrlimit/setrlimit use task_lock(current->group_leader) to 781 * protect this instead of the siglock, because they really 782 * have no need to disable irqs. 783 */ 784 struct rlimit rlim[RLIM_NLIMITS]; 785 786 #ifdef CONFIG_BSD_PROCESS_ACCT 787 struct pacct_struct pacct; /* per-process accounting information */ 788 #endif 789 #ifdef CONFIG_TASKSTATS 790 struct taskstats *stats; 791 #endif 792 #ifdef CONFIG_AUDIT 793 unsigned audit_tty; 794 struct tty_audit_buf *tty_audit_buf; 795 #endif 796 797 /* 798 * Thread is the potential origin of an oom condition; kill first on 799 * oom 800 */ 801 bool oom_flag_origin; 802 short oom_score_adj; /* OOM kill score adjustment */ 803 short oom_score_adj_min; /* OOM kill score adjustment min value. 804 * Only settable by CAP_SYS_RESOURCE. */ 805 806 struct mutex cred_guard_mutex; /* guard against foreign influences on 807 * credential calculations 808 * (notably. ptrace) */ 809 }; 810 811 /* 812 * Bits in flags field of signal_struct. 813 */ 814 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 815 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 816 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 817 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 818 /* 819 * Pending notifications to parent. 820 */ 821 #define SIGNAL_CLD_STOPPED 0x00000010 822 #define SIGNAL_CLD_CONTINUED 0x00000020 823 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 824 825 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 826 827 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 828 static inline int signal_group_exit(const struct signal_struct *sig) 829 { 830 return (sig->flags & SIGNAL_GROUP_EXIT) || 831 (sig->group_exit_task != NULL); 832 } 833 834 /* 835 * Some day this will be a full-fledged user tracking system.. 836 */ 837 struct user_struct { 838 atomic_t __count; /* reference count */ 839 atomic_t processes; /* How many processes does this user have? */ 840 atomic_t sigpending; /* How many pending signals does this user have? */ 841 #ifdef CONFIG_INOTIFY_USER 842 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 843 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 844 #endif 845 #ifdef CONFIG_FANOTIFY 846 atomic_t fanotify_listeners; 847 #endif 848 #ifdef CONFIG_EPOLL 849 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 850 #endif 851 #ifdef CONFIG_POSIX_MQUEUE 852 /* protected by mq_lock */ 853 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 854 #endif 855 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 856 unsigned long unix_inflight; /* How many files in flight in unix sockets */ 857 atomic_long_t pipe_bufs; /* how many pages are allocated in pipe buffers */ 858 859 #ifdef CONFIG_KEYS 860 struct key *uid_keyring; /* UID specific keyring */ 861 struct key *session_keyring; /* UID's default session keyring */ 862 #endif 863 864 /* Hash table maintenance information */ 865 struct hlist_node uidhash_node; 866 kuid_t uid; 867 868 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL) 869 atomic_long_t locked_vm; 870 #endif 871 }; 872 873 extern int uids_sysfs_init(void); 874 875 extern struct user_struct *find_user(kuid_t); 876 877 extern struct user_struct root_user; 878 #define INIT_USER (&root_user) 879 880 881 struct backing_dev_info; 882 struct reclaim_state; 883 884 #ifdef CONFIG_SCHED_INFO 885 struct sched_info { 886 /* cumulative counters */ 887 unsigned long pcount; /* # of times run on this cpu */ 888 unsigned long long run_delay; /* time spent waiting on a runqueue */ 889 890 /* timestamps */ 891 unsigned long long last_arrival,/* when we last ran on a cpu */ 892 last_queued; /* when we were last queued to run */ 893 }; 894 #endif /* CONFIG_SCHED_INFO */ 895 896 #ifdef CONFIG_TASK_DELAY_ACCT 897 struct task_delay_info { 898 spinlock_t lock; 899 unsigned int flags; /* Private per-task flags */ 900 901 /* For each stat XXX, add following, aligned appropriately 902 * 903 * struct timespec XXX_start, XXX_end; 904 * u64 XXX_delay; 905 * u32 XXX_count; 906 * 907 * Atomicity of updates to XXX_delay, XXX_count protected by 908 * single lock above (split into XXX_lock if contention is an issue). 909 */ 910 911 /* 912 * XXX_count is incremented on every XXX operation, the delay 913 * associated with the operation is added to XXX_delay. 914 * XXX_delay contains the accumulated delay time in nanoseconds. 915 */ 916 u64 blkio_start; /* Shared by blkio, swapin */ 917 u64 blkio_delay; /* wait for sync block io completion */ 918 u64 swapin_delay; /* wait for swapin block io completion */ 919 u32 blkio_count; /* total count of the number of sync block */ 920 /* io operations performed */ 921 u32 swapin_count; /* total count of the number of swapin block */ 922 /* io operations performed */ 923 924 u64 freepages_start; 925 u64 freepages_delay; /* wait for memory reclaim */ 926 u32 freepages_count; /* total count of memory reclaim */ 927 }; 928 #endif /* CONFIG_TASK_DELAY_ACCT */ 929 930 static inline int sched_info_on(void) 931 { 932 #ifdef CONFIG_SCHEDSTATS 933 return 1; 934 #elif defined(CONFIG_TASK_DELAY_ACCT) 935 extern int delayacct_on; 936 return delayacct_on; 937 #else 938 return 0; 939 #endif 940 } 941 942 #ifdef CONFIG_SCHEDSTATS 943 void force_schedstat_enabled(void); 944 #endif 945 946 enum cpu_idle_type { 947 CPU_IDLE, 948 CPU_NOT_IDLE, 949 CPU_NEWLY_IDLE, 950 CPU_MAX_IDLE_TYPES 951 }; 952 953 /* 954 * Integer metrics need fixed point arithmetic, e.g., sched/fair 955 * has a few: load, load_avg, util_avg, freq, and capacity. 956 * 957 * We define a basic fixed point arithmetic range, and then formalize 958 * all these metrics based on that basic range. 959 */ 960 # define SCHED_FIXEDPOINT_SHIFT 10 961 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 962 963 /* 964 * Increase resolution of cpu_capacity calculations 965 */ 966 #define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 967 #define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 968 969 /* 970 * Wake-queues are lists of tasks with a pending wakeup, whose 971 * callers have already marked the task as woken internally, 972 * and can thus carry on. A common use case is being able to 973 * do the wakeups once the corresponding user lock as been 974 * released. 975 * 976 * We hold reference to each task in the list across the wakeup, 977 * thus guaranteeing that the memory is still valid by the time 978 * the actual wakeups are performed in wake_up_q(). 979 * 980 * One per task suffices, because there's never a need for a task to be 981 * in two wake queues simultaneously; it is forbidden to abandon a task 982 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is 983 * already in a wake queue, the wakeup will happen soon and the second 984 * waker can just skip it. 985 * 986 * The WAKE_Q macro declares and initializes the list head. 987 * wake_up_q() does NOT reinitialize the list; it's expected to be 988 * called near the end of a function, where the fact that the queue is 989 * not used again will be easy to see by inspection. 990 * 991 * Note that this can cause spurious wakeups. schedule() callers 992 * must ensure the call is done inside a loop, confirming that the 993 * wakeup condition has in fact occurred. 994 */ 995 struct wake_q_node { 996 struct wake_q_node *next; 997 }; 998 999 struct wake_q_head { 1000 struct wake_q_node *first; 1001 struct wake_q_node **lastp; 1002 }; 1003 1004 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01) 1005 1006 #define WAKE_Q(name) \ 1007 struct wake_q_head name = { WAKE_Q_TAIL, &name.first } 1008 1009 extern void wake_q_add(struct wake_q_head *head, 1010 struct task_struct *task); 1011 extern void wake_up_q(struct wake_q_head *head); 1012 1013 /* 1014 * sched-domains (multiprocessor balancing) declarations: 1015 */ 1016 #ifdef CONFIG_SMP 1017 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 1018 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 1019 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 1020 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 1021 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 1022 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 1023 #define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu power */ 1024 #define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ 1025 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 1026 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 1027 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 1028 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 1029 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 1030 #define SD_NUMA 0x4000 /* cross-node balancing */ 1031 1032 #ifdef CONFIG_SCHED_SMT 1033 static inline int cpu_smt_flags(void) 1034 { 1035 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; 1036 } 1037 #endif 1038 1039 #ifdef CONFIG_SCHED_MC 1040 static inline int cpu_core_flags(void) 1041 { 1042 return SD_SHARE_PKG_RESOURCES; 1043 } 1044 #endif 1045 1046 #ifdef CONFIG_NUMA 1047 static inline int cpu_numa_flags(void) 1048 { 1049 return SD_NUMA; 1050 } 1051 #endif 1052 1053 struct sched_domain_attr { 1054 int relax_domain_level; 1055 }; 1056 1057 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 1058 .relax_domain_level = -1, \ 1059 } 1060 1061 extern int sched_domain_level_max; 1062 1063 struct sched_group; 1064 1065 struct sched_domain { 1066 /* These fields must be setup */ 1067 struct sched_domain *parent; /* top domain must be null terminated */ 1068 struct sched_domain *child; /* bottom domain must be null terminated */ 1069 struct sched_group *groups; /* the balancing groups of the domain */ 1070 unsigned long min_interval; /* Minimum balance interval ms */ 1071 unsigned long max_interval; /* Maximum balance interval ms */ 1072 unsigned int busy_factor; /* less balancing by factor if busy */ 1073 unsigned int imbalance_pct; /* No balance until over watermark */ 1074 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 1075 unsigned int busy_idx; 1076 unsigned int idle_idx; 1077 unsigned int newidle_idx; 1078 unsigned int wake_idx; 1079 unsigned int forkexec_idx; 1080 unsigned int smt_gain; 1081 1082 int nohz_idle; /* NOHZ IDLE status */ 1083 int flags; /* See SD_* */ 1084 int level; 1085 1086 /* Runtime fields. */ 1087 unsigned long last_balance; /* init to jiffies. units in jiffies */ 1088 unsigned int balance_interval; /* initialise to 1. units in ms. */ 1089 unsigned int nr_balance_failed; /* initialise to 0 */ 1090 1091 /* idle_balance() stats */ 1092 u64 max_newidle_lb_cost; 1093 unsigned long next_decay_max_lb_cost; 1094 1095 #ifdef CONFIG_SCHEDSTATS 1096 /* load_balance() stats */ 1097 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 1098 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 1099 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 1100 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 1101 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 1102 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 1103 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 1104 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 1105 1106 /* Active load balancing */ 1107 unsigned int alb_count; 1108 unsigned int alb_failed; 1109 unsigned int alb_pushed; 1110 1111 /* SD_BALANCE_EXEC stats */ 1112 unsigned int sbe_count; 1113 unsigned int sbe_balanced; 1114 unsigned int sbe_pushed; 1115 1116 /* SD_BALANCE_FORK stats */ 1117 unsigned int sbf_count; 1118 unsigned int sbf_balanced; 1119 unsigned int sbf_pushed; 1120 1121 /* try_to_wake_up() stats */ 1122 unsigned int ttwu_wake_remote; 1123 unsigned int ttwu_move_affine; 1124 unsigned int ttwu_move_balance; 1125 #endif 1126 #ifdef CONFIG_SCHED_DEBUG 1127 char *name; 1128 #endif 1129 union { 1130 void *private; /* used during construction */ 1131 struct rcu_head rcu; /* used during destruction */ 1132 }; 1133 1134 unsigned int span_weight; 1135 /* 1136 * Span of all CPUs in this domain. 1137 * 1138 * NOTE: this field is variable length. (Allocated dynamically 1139 * by attaching extra space to the end of the structure, 1140 * depending on how many CPUs the kernel has booted up with) 1141 */ 1142 unsigned long span[0]; 1143 }; 1144 1145 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 1146 { 1147 return to_cpumask(sd->span); 1148 } 1149 1150 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1151 struct sched_domain_attr *dattr_new); 1152 1153 /* Allocate an array of sched domains, for partition_sched_domains(). */ 1154 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 1155 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 1156 1157 bool cpus_share_cache(int this_cpu, int that_cpu); 1158 1159 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); 1160 typedef int (*sched_domain_flags_f)(void); 1161 1162 #define SDTL_OVERLAP 0x01 1163 1164 struct sd_data { 1165 struct sched_domain **__percpu sd; 1166 struct sched_group **__percpu sg; 1167 struct sched_group_capacity **__percpu sgc; 1168 }; 1169 1170 struct sched_domain_topology_level { 1171 sched_domain_mask_f mask; 1172 sched_domain_flags_f sd_flags; 1173 int flags; 1174 int numa_level; 1175 struct sd_data data; 1176 #ifdef CONFIG_SCHED_DEBUG 1177 char *name; 1178 #endif 1179 }; 1180 1181 extern void set_sched_topology(struct sched_domain_topology_level *tl); 1182 extern void wake_up_if_idle(int cpu); 1183 1184 #ifdef CONFIG_SCHED_DEBUG 1185 # define SD_INIT_NAME(type) .name = #type 1186 #else 1187 # define SD_INIT_NAME(type) 1188 #endif 1189 1190 #else /* CONFIG_SMP */ 1191 1192 struct sched_domain_attr; 1193 1194 static inline void 1195 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1196 struct sched_domain_attr *dattr_new) 1197 { 1198 } 1199 1200 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1201 { 1202 return true; 1203 } 1204 1205 #endif /* !CONFIG_SMP */ 1206 1207 1208 struct io_context; /* See blkdev.h */ 1209 1210 1211 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1212 extern void prefetch_stack(struct task_struct *t); 1213 #else 1214 static inline void prefetch_stack(struct task_struct *t) { } 1215 #endif 1216 1217 struct audit_context; /* See audit.c */ 1218 struct mempolicy; 1219 struct pipe_inode_info; 1220 struct uts_namespace; 1221 1222 struct load_weight { 1223 unsigned long weight; 1224 u32 inv_weight; 1225 }; 1226 1227 /* 1228 * The load_avg/util_avg accumulates an infinite geometric series 1229 * (see __update_load_avg() in kernel/sched/fair.c). 1230 * 1231 * [load_avg definition] 1232 * 1233 * load_avg = runnable% * scale_load_down(load) 1234 * 1235 * where runnable% is the time ratio that a sched_entity is runnable. 1236 * For cfs_rq, it is the aggregated load_avg of all runnable and 1237 * blocked sched_entities. 1238 * 1239 * load_avg may also take frequency scaling into account: 1240 * 1241 * load_avg = runnable% * scale_load_down(load) * freq% 1242 * 1243 * where freq% is the CPU frequency normalized to the highest frequency. 1244 * 1245 * [util_avg definition] 1246 * 1247 * util_avg = running% * SCHED_CAPACITY_SCALE 1248 * 1249 * where running% is the time ratio that a sched_entity is running on 1250 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable 1251 * and blocked sched_entities. 1252 * 1253 * util_avg may also factor frequency scaling and CPU capacity scaling: 1254 * 1255 * util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity% 1256 * 1257 * where freq% is the same as above, and capacity% is the CPU capacity 1258 * normalized to the greatest capacity (due to uarch differences, etc). 1259 * 1260 * N.B., the above ratios (runnable%, running%, freq%, and capacity%) 1261 * themselves are in the range of [0, 1]. To do fixed point arithmetics, 1262 * we therefore scale them to as large a range as necessary. This is for 1263 * example reflected by util_avg's SCHED_CAPACITY_SCALE. 1264 * 1265 * [Overflow issue] 1266 * 1267 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 1268 * with the highest load (=88761), always runnable on a single cfs_rq, 1269 * and should not overflow as the number already hits PID_MAX_LIMIT. 1270 * 1271 * For all other cases (including 32-bit kernels), struct load_weight's 1272 * weight will overflow first before we do, because: 1273 * 1274 * Max(load_avg) <= Max(load.weight) 1275 * 1276 * Then it is the load_weight's responsibility to consider overflow 1277 * issues. 1278 */ 1279 struct sched_avg { 1280 u64 last_update_time, load_sum; 1281 u32 util_sum, period_contrib; 1282 unsigned long load_avg, util_avg; 1283 }; 1284 1285 #ifdef CONFIG_SCHEDSTATS 1286 struct sched_statistics { 1287 u64 wait_start; 1288 u64 wait_max; 1289 u64 wait_count; 1290 u64 wait_sum; 1291 u64 iowait_count; 1292 u64 iowait_sum; 1293 1294 u64 sleep_start; 1295 u64 sleep_max; 1296 s64 sum_sleep_runtime; 1297 1298 u64 block_start; 1299 u64 block_max; 1300 u64 exec_max; 1301 u64 slice_max; 1302 1303 u64 nr_migrations_cold; 1304 u64 nr_failed_migrations_affine; 1305 u64 nr_failed_migrations_running; 1306 u64 nr_failed_migrations_hot; 1307 u64 nr_forced_migrations; 1308 1309 u64 nr_wakeups; 1310 u64 nr_wakeups_sync; 1311 u64 nr_wakeups_migrate; 1312 u64 nr_wakeups_local; 1313 u64 nr_wakeups_remote; 1314 u64 nr_wakeups_affine; 1315 u64 nr_wakeups_affine_attempts; 1316 u64 nr_wakeups_passive; 1317 u64 nr_wakeups_idle; 1318 }; 1319 #endif 1320 1321 struct sched_entity { 1322 struct load_weight load; /* for load-balancing */ 1323 struct rb_node run_node; 1324 struct list_head group_node; 1325 unsigned int on_rq; 1326 1327 u64 exec_start; 1328 u64 sum_exec_runtime; 1329 u64 vruntime; 1330 u64 prev_sum_exec_runtime; 1331 1332 u64 nr_migrations; 1333 1334 #ifdef CONFIG_SCHEDSTATS 1335 struct sched_statistics statistics; 1336 #endif 1337 1338 #ifdef CONFIG_FAIR_GROUP_SCHED 1339 int depth; 1340 struct sched_entity *parent; 1341 /* rq on which this entity is (to be) queued: */ 1342 struct cfs_rq *cfs_rq; 1343 /* rq "owned" by this entity/group: */ 1344 struct cfs_rq *my_q; 1345 #endif 1346 1347 #ifdef CONFIG_SMP 1348 /* 1349 * Per entity load average tracking. 1350 * 1351 * Put into separate cache line so it does not 1352 * collide with read-mostly values above. 1353 */ 1354 struct sched_avg avg ____cacheline_aligned_in_smp; 1355 #endif 1356 }; 1357 1358 struct sched_rt_entity { 1359 struct list_head run_list; 1360 unsigned long timeout; 1361 unsigned long watchdog_stamp; 1362 unsigned int time_slice; 1363 unsigned short on_rq; 1364 unsigned short on_list; 1365 1366 struct sched_rt_entity *back; 1367 #ifdef CONFIG_RT_GROUP_SCHED 1368 struct sched_rt_entity *parent; 1369 /* rq on which this entity is (to be) queued: */ 1370 struct rt_rq *rt_rq; 1371 /* rq "owned" by this entity/group: */ 1372 struct rt_rq *my_q; 1373 #endif 1374 }; 1375 1376 struct sched_dl_entity { 1377 struct rb_node rb_node; 1378 1379 /* 1380 * Original scheduling parameters. Copied here from sched_attr 1381 * during sched_setattr(), they will remain the same until 1382 * the next sched_setattr(). 1383 */ 1384 u64 dl_runtime; /* maximum runtime for each instance */ 1385 u64 dl_deadline; /* relative deadline of each instance */ 1386 u64 dl_period; /* separation of two instances (period) */ 1387 u64 dl_bw; /* dl_runtime / dl_deadline */ 1388 1389 /* 1390 * Actual scheduling parameters. Initialized with the values above, 1391 * they are continously updated during task execution. Note that 1392 * the remaining runtime could be < 0 in case we are in overrun. 1393 */ 1394 s64 runtime; /* remaining runtime for this instance */ 1395 u64 deadline; /* absolute deadline for this instance */ 1396 unsigned int flags; /* specifying the scheduler behaviour */ 1397 1398 /* 1399 * Some bool flags: 1400 * 1401 * @dl_throttled tells if we exhausted the runtime. If so, the 1402 * task has to wait for a replenishment to be performed at the 1403 * next firing of dl_timer. 1404 * 1405 * @dl_boosted tells if we are boosted due to DI. If so we are 1406 * outside bandwidth enforcement mechanism (but only until we 1407 * exit the critical section); 1408 * 1409 * @dl_yielded tells if task gave up the cpu before consuming 1410 * all its available runtime during the last job. 1411 */ 1412 int dl_throttled, dl_boosted, dl_yielded; 1413 1414 /* 1415 * Bandwidth enforcement timer. Each -deadline task has its 1416 * own bandwidth to be enforced, thus we need one timer per task. 1417 */ 1418 struct hrtimer dl_timer; 1419 }; 1420 1421 union rcu_special { 1422 struct { 1423 u8 blocked; 1424 u8 need_qs; 1425 u8 exp_need_qs; 1426 u8 pad; /* Otherwise the compiler can store garbage here. */ 1427 } b; /* Bits. */ 1428 u32 s; /* Set of bits. */ 1429 }; 1430 struct rcu_node; 1431 1432 enum perf_event_task_context { 1433 perf_invalid_context = -1, 1434 perf_hw_context = 0, 1435 perf_sw_context, 1436 perf_nr_task_contexts, 1437 }; 1438 1439 /* Track pages that require TLB flushes */ 1440 struct tlbflush_unmap_batch { 1441 /* 1442 * Each bit set is a CPU that potentially has a TLB entry for one of 1443 * the PFNs being flushed. See set_tlb_ubc_flush_pending(). 1444 */ 1445 struct cpumask cpumask; 1446 1447 /* True if any bit in cpumask is set */ 1448 bool flush_required; 1449 1450 /* 1451 * If true then the PTE was dirty when unmapped. The entry must be 1452 * flushed before IO is initiated or a stale TLB entry potentially 1453 * allows an update without redirtying the page. 1454 */ 1455 bool writable; 1456 }; 1457 1458 struct task_struct { 1459 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1460 void *stack; 1461 atomic_t usage; 1462 unsigned int flags; /* per process flags, defined below */ 1463 unsigned int ptrace; 1464 1465 #ifdef CONFIG_SMP 1466 struct llist_node wake_entry; 1467 int on_cpu; 1468 unsigned int wakee_flips; 1469 unsigned long wakee_flip_decay_ts; 1470 struct task_struct *last_wakee; 1471 1472 int wake_cpu; 1473 #endif 1474 int on_rq; 1475 1476 int prio, static_prio, normal_prio; 1477 unsigned int rt_priority; 1478 const struct sched_class *sched_class; 1479 struct sched_entity se; 1480 struct sched_rt_entity rt; 1481 #ifdef CONFIG_CGROUP_SCHED 1482 struct task_group *sched_task_group; 1483 #endif 1484 struct sched_dl_entity dl; 1485 1486 #ifdef CONFIG_PREEMPT_NOTIFIERS 1487 /* list of struct preempt_notifier: */ 1488 struct hlist_head preempt_notifiers; 1489 #endif 1490 1491 #ifdef CONFIG_BLK_DEV_IO_TRACE 1492 unsigned int btrace_seq; 1493 #endif 1494 1495 unsigned int policy; 1496 int nr_cpus_allowed; 1497 cpumask_t cpus_allowed; 1498 1499 #ifdef CONFIG_PREEMPT_RCU 1500 int rcu_read_lock_nesting; 1501 union rcu_special rcu_read_unlock_special; 1502 struct list_head rcu_node_entry; 1503 struct rcu_node *rcu_blocked_node; 1504 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1505 #ifdef CONFIG_TASKS_RCU 1506 unsigned long rcu_tasks_nvcsw; 1507 bool rcu_tasks_holdout; 1508 struct list_head rcu_tasks_holdout_list; 1509 int rcu_tasks_idle_cpu; 1510 #endif /* #ifdef CONFIG_TASKS_RCU */ 1511 1512 #ifdef CONFIG_SCHED_INFO 1513 struct sched_info sched_info; 1514 #endif 1515 1516 struct list_head tasks; 1517 #ifdef CONFIG_SMP 1518 struct plist_node pushable_tasks; 1519 struct rb_node pushable_dl_tasks; 1520 #endif 1521 1522 struct mm_struct *mm, *active_mm; 1523 /* per-thread vma caching */ 1524 u32 vmacache_seqnum; 1525 struct vm_area_struct *vmacache[VMACACHE_SIZE]; 1526 #if defined(SPLIT_RSS_COUNTING) 1527 struct task_rss_stat rss_stat; 1528 #endif 1529 /* task state */ 1530 int exit_state; 1531 int exit_code, exit_signal; 1532 int pdeath_signal; /* The signal sent when the parent dies */ 1533 unsigned long jobctl; /* JOBCTL_*, siglock protected */ 1534 1535 /* Used for emulating ABI behavior of previous Linux versions */ 1536 unsigned int personality; 1537 1538 /* scheduler bits, serialized by scheduler locks */ 1539 unsigned sched_reset_on_fork:1; 1540 unsigned sched_contributes_to_load:1; 1541 unsigned sched_migrated:1; 1542 unsigned sched_remote_wakeup:1; 1543 unsigned :0; /* force alignment to the next boundary */ 1544 1545 /* unserialized, strictly 'current' */ 1546 unsigned in_execve:1; /* bit to tell LSMs we're in execve */ 1547 unsigned in_iowait:1; 1548 #ifdef CONFIG_MEMCG 1549 unsigned memcg_may_oom:1; 1550 #ifndef CONFIG_SLOB 1551 unsigned memcg_kmem_skip_account:1; 1552 #endif 1553 #endif 1554 #ifdef CONFIG_COMPAT_BRK 1555 unsigned brk_randomized:1; 1556 #endif 1557 1558 unsigned long atomic_flags; /* Flags needing atomic access. */ 1559 1560 struct restart_block restart_block; 1561 1562 pid_t pid; 1563 pid_t tgid; 1564 1565 #ifdef CONFIG_CC_STACKPROTECTOR 1566 /* Canary value for the -fstack-protector gcc feature */ 1567 unsigned long stack_canary; 1568 #endif 1569 /* 1570 * pointers to (original) parent process, youngest child, younger sibling, 1571 * older sibling, respectively. (p->father can be replaced with 1572 * p->real_parent->pid) 1573 */ 1574 struct task_struct __rcu *real_parent; /* real parent process */ 1575 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1576 /* 1577 * children/sibling forms the list of my natural children 1578 */ 1579 struct list_head children; /* list of my children */ 1580 struct list_head sibling; /* linkage in my parent's children list */ 1581 struct task_struct *group_leader; /* threadgroup leader */ 1582 1583 /* 1584 * ptraced is the list of tasks this task is using ptrace on. 1585 * This includes both natural children and PTRACE_ATTACH targets. 1586 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1587 */ 1588 struct list_head ptraced; 1589 struct list_head ptrace_entry; 1590 1591 /* PID/PID hash table linkage. */ 1592 struct pid_link pids[PIDTYPE_MAX]; 1593 struct list_head thread_group; 1594 struct list_head thread_node; 1595 1596 struct completion *vfork_done; /* for vfork() */ 1597 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1598 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1599 1600 cputime_t utime, stime, utimescaled, stimescaled; 1601 cputime_t gtime; 1602 struct prev_cputime prev_cputime; 1603 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1604 seqcount_t vtime_seqcount; 1605 unsigned long long vtime_snap; 1606 enum { 1607 /* Task is sleeping or running in a CPU with VTIME inactive */ 1608 VTIME_INACTIVE = 0, 1609 /* Task runs in userspace in a CPU with VTIME active */ 1610 VTIME_USER, 1611 /* Task runs in kernelspace in a CPU with VTIME active */ 1612 VTIME_SYS, 1613 } vtime_snap_whence; 1614 #endif 1615 1616 #ifdef CONFIG_NO_HZ_FULL 1617 atomic_t tick_dep_mask; 1618 #endif 1619 unsigned long nvcsw, nivcsw; /* context switch counts */ 1620 u64 start_time; /* monotonic time in nsec */ 1621 u64 real_start_time; /* boot based time in nsec */ 1622 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1623 unsigned long min_flt, maj_flt; 1624 1625 struct task_cputime cputime_expires; 1626 struct list_head cpu_timers[3]; 1627 1628 /* process credentials */ 1629 const struct cred __rcu *real_cred; /* objective and real subjective task 1630 * credentials (COW) */ 1631 const struct cred __rcu *cred; /* effective (overridable) subjective task 1632 * credentials (COW) */ 1633 char comm[TASK_COMM_LEN]; /* executable name excluding path 1634 - access with [gs]et_task_comm (which lock 1635 it with task_lock()) 1636 - initialized normally by setup_new_exec */ 1637 /* file system info */ 1638 struct nameidata *nameidata; 1639 #ifdef CONFIG_SYSVIPC 1640 /* ipc stuff */ 1641 struct sysv_sem sysvsem; 1642 struct sysv_shm sysvshm; 1643 #endif 1644 #ifdef CONFIG_DETECT_HUNG_TASK 1645 /* hung task detection */ 1646 unsigned long last_switch_count; 1647 #endif 1648 /* filesystem information */ 1649 struct fs_struct *fs; 1650 /* open file information */ 1651 struct files_struct *files; 1652 /* namespaces */ 1653 struct nsproxy *nsproxy; 1654 /* signal handlers */ 1655 struct signal_struct *signal; 1656 struct sighand_struct *sighand; 1657 1658 sigset_t blocked, real_blocked; 1659 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1660 struct sigpending pending; 1661 1662 unsigned long sas_ss_sp; 1663 size_t sas_ss_size; 1664 unsigned sas_ss_flags; 1665 1666 struct callback_head *task_works; 1667 1668 struct audit_context *audit_context; 1669 #ifdef CONFIG_AUDITSYSCALL 1670 kuid_t loginuid; 1671 unsigned int sessionid; 1672 #endif 1673 struct seccomp seccomp; 1674 1675 /* Thread group tracking */ 1676 u32 parent_exec_id; 1677 u32 self_exec_id; 1678 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1679 * mempolicy */ 1680 spinlock_t alloc_lock; 1681 1682 /* Protection of the PI data structures: */ 1683 raw_spinlock_t pi_lock; 1684 1685 struct wake_q_node wake_q; 1686 1687 #ifdef CONFIG_RT_MUTEXES 1688 /* PI waiters blocked on a rt_mutex held by this task */ 1689 struct rb_root pi_waiters; 1690 struct rb_node *pi_waiters_leftmost; 1691 /* Deadlock detection and priority inheritance handling */ 1692 struct rt_mutex_waiter *pi_blocked_on; 1693 #endif 1694 1695 #ifdef CONFIG_DEBUG_MUTEXES 1696 /* mutex deadlock detection */ 1697 struct mutex_waiter *blocked_on; 1698 #endif 1699 #ifdef CONFIG_TRACE_IRQFLAGS 1700 unsigned int irq_events; 1701 unsigned long hardirq_enable_ip; 1702 unsigned long hardirq_disable_ip; 1703 unsigned int hardirq_enable_event; 1704 unsigned int hardirq_disable_event; 1705 int hardirqs_enabled; 1706 int hardirq_context; 1707 unsigned long softirq_disable_ip; 1708 unsigned long softirq_enable_ip; 1709 unsigned int softirq_disable_event; 1710 unsigned int softirq_enable_event; 1711 int softirqs_enabled; 1712 int softirq_context; 1713 #endif 1714 #ifdef CONFIG_LOCKDEP 1715 # define MAX_LOCK_DEPTH 48UL 1716 u64 curr_chain_key; 1717 int lockdep_depth; 1718 unsigned int lockdep_recursion; 1719 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1720 gfp_t lockdep_reclaim_gfp; 1721 #endif 1722 #ifdef CONFIG_UBSAN 1723 unsigned int in_ubsan; 1724 #endif 1725 1726 /* journalling filesystem info */ 1727 void *journal_info; 1728 1729 /* stacked block device info */ 1730 struct bio_list *bio_list; 1731 1732 #ifdef CONFIG_BLOCK 1733 /* stack plugging */ 1734 struct blk_plug *plug; 1735 #endif 1736 1737 /* VM state */ 1738 struct reclaim_state *reclaim_state; 1739 1740 struct backing_dev_info *backing_dev_info; 1741 1742 struct io_context *io_context; 1743 1744 unsigned long ptrace_message; 1745 siginfo_t *last_siginfo; /* For ptrace use. */ 1746 struct task_io_accounting ioac; 1747 #if defined(CONFIG_TASK_XACCT) 1748 u64 acct_rss_mem1; /* accumulated rss usage */ 1749 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1750 cputime_t acct_timexpd; /* stime + utime since last update */ 1751 #endif 1752 #ifdef CONFIG_CPUSETS 1753 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1754 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1755 int cpuset_mem_spread_rotor; 1756 int cpuset_slab_spread_rotor; 1757 #endif 1758 #ifdef CONFIG_CGROUPS 1759 /* Control Group info protected by css_set_lock */ 1760 struct css_set __rcu *cgroups; 1761 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1762 struct list_head cg_list; 1763 #endif 1764 #ifdef CONFIG_FUTEX 1765 struct robust_list_head __user *robust_list; 1766 #ifdef CONFIG_COMPAT 1767 struct compat_robust_list_head __user *compat_robust_list; 1768 #endif 1769 struct list_head pi_state_list; 1770 struct futex_pi_state *pi_state_cache; 1771 #endif 1772 #ifdef CONFIG_PERF_EVENTS 1773 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1774 struct mutex perf_event_mutex; 1775 struct list_head perf_event_list; 1776 #endif 1777 #ifdef CONFIG_DEBUG_PREEMPT 1778 unsigned long preempt_disable_ip; 1779 #endif 1780 #ifdef CONFIG_NUMA 1781 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1782 short il_next; 1783 short pref_node_fork; 1784 #endif 1785 #ifdef CONFIG_NUMA_BALANCING 1786 int numa_scan_seq; 1787 unsigned int numa_scan_period; 1788 unsigned int numa_scan_period_max; 1789 int numa_preferred_nid; 1790 unsigned long numa_migrate_retry; 1791 u64 node_stamp; /* migration stamp */ 1792 u64 last_task_numa_placement; 1793 u64 last_sum_exec_runtime; 1794 struct callback_head numa_work; 1795 1796 struct list_head numa_entry; 1797 struct numa_group *numa_group; 1798 1799 /* 1800 * numa_faults is an array split into four regions: 1801 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1802 * in this precise order. 1803 * 1804 * faults_memory: Exponential decaying average of faults on a per-node 1805 * basis. Scheduling placement decisions are made based on these 1806 * counts. The values remain static for the duration of a PTE scan. 1807 * faults_cpu: Track the nodes the process was running on when a NUMA 1808 * hinting fault was incurred. 1809 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1810 * during the current scan window. When the scan completes, the counts 1811 * in faults_memory and faults_cpu decay and these values are copied. 1812 */ 1813 unsigned long *numa_faults; 1814 unsigned long total_numa_faults; 1815 1816 /* 1817 * numa_faults_locality tracks if faults recorded during the last 1818 * scan window were remote/local or failed to migrate. The task scan 1819 * period is adapted based on the locality of the faults with different 1820 * weights depending on whether they were shared or private faults 1821 */ 1822 unsigned long numa_faults_locality[3]; 1823 1824 unsigned long numa_pages_migrated; 1825 #endif /* CONFIG_NUMA_BALANCING */ 1826 1827 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 1828 struct tlbflush_unmap_batch tlb_ubc; 1829 #endif 1830 1831 struct rcu_head rcu; 1832 1833 /* 1834 * cache last used pipe for splice 1835 */ 1836 struct pipe_inode_info *splice_pipe; 1837 1838 struct page_frag task_frag; 1839 1840 #ifdef CONFIG_TASK_DELAY_ACCT 1841 struct task_delay_info *delays; 1842 #endif 1843 #ifdef CONFIG_FAULT_INJECTION 1844 int make_it_fail; 1845 #endif 1846 /* 1847 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1848 * balance_dirty_pages() for some dirty throttling pause 1849 */ 1850 int nr_dirtied; 1851 int nr_dirtied_pause; 1852 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1853 1854 #ifdef CONFIG_LATENCYTOP 1855 int latency_record_count; 1856 struct latency_record latency_record[LT_SAVECOUNT]; 1857 #endif 1858 /* 1859 * time slack values; these are used to round up poll() and 1860 * select() etc timeout values. These are in nanoseconds. 1861 */ 1862 u64 timer_slack_ns; 1863 u64 default_timer_slack_ns; 1864 1865 #ifdef CONFIG_KASAN 1866 unsigned int kasan_depth; 1867 #endif 1868 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1869 /* Index of current stored address in ret_stack */ 1870 int curr_ret_stack; 1871 /* Stack of return addresses for return function tracing */ 1872 struct ftrace_ret_stack *ret_stack; 1873 /* time stamp for last schedule */ 1874 unsigned long long ftrace_timestamp; 1875 /* 1876 * Number of functions that haven't been traced 1877 * because of depth overrun. 1878 */ 1879 atomic_t trace_overrun; 1880 /* Pause for the tracing */ 1881 atomic_t tracing_graph_pause; 1882 #endif 1883 #ifdef CONFIG_TRACING 1884 /* state flags for use by tracers */ 1885 unsigned long trace; 1886 /* bitmask and counter of trace recursion */ 1887 unsigned long trace_recursion; 1888 #endif /* CONFIG_TRACING */ 1889 #ifdef CONFIG_KCOV 1890 /* Coverage collection mode enabled for this task (0 if disabled). */ 1891 enum kcov_mode kcov_mode; 1892 /* Size of the kcov_area. */ 1893 unsigned kcov_size; 1894 /* Buffer for coverage collection. */ 1895 void *kcov_area; 1896 /* kcov desciptor wired with this task or NULL. */ 1897 struct kcov *kcov; 1898 #endif 1899 #ifdef CONFIG_MEMCG 1900 struct mem_cgroup *memcg_in_oom; 1901 gfp_t memcg_oom_gfp_mask; 1902 int memcg_oom_order; 1903 1904 /* number of pages to reclaim on returning to userland */ 1905 unsigned int memcg_nr_pages_over_high; 1906 #endif 1907 #ifdef CONFIG_UPROBES 1908 struct uprobe_task *utask; 1909 #endif 1910 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1911 unsigned int sequential_io; 1912 unsigned int sequential_io_avg; 1913 #endif 1914 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1915 unsigned long task_state_change; 1916 #endif 1917 int pagefault_disabled; 1918 #ifdef CONFIG_MMU 1919 struct task_struct *oom_reaper_list; 1920 #endif 1921 /* CPU-specific state of this task */ 1922 struct thread_struct thread; 1923 /* 1924 * WARNING: on x86, 'thread_struct' contains a variable-sized 1925 * structure. It *MUST* be at the end of 'task_struct'. 1926 * 1927 * Do not put anything below here! 1928 */ 1929 }; 1930 1931 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT 1932 extern int arch_task_struct_size __read_mostly; 1933 #else 1934 # define arch_task_struct_size (sizeof(struct task_struct)) 1935 #endif 1936 1937 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1938 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1939 1940 static inline int tsk_nr_cpus_allowed(struct task_struct *p) 1941 { 1942 return p->nr_cpus_allowed; 1943 } 1944 1945 #define TNF_MIGRATED 0x01 1946 #define TNF_NO_GROUP 0x02 1947 #define TNF_SHARED 0x04 1948 #define TNF_FAULT_LOCAL 0x08 1949 #define TNF_MIGRATE_FAIL 0x10 1950 1951 #ifdef CONFIG_NUMA_BALANCING 1952 extern void task_numa_fault(int last_node, int node, int pages, int flags); 1953 extern pid_t task_numa_group_id(struct task_struct *p); 1954 extern void set_numabalancing_state(bool enabled); 1955 extern void task_numa_free(struct task_struct *p); 1956 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page, 1957 int src_nid, int dst_cpu); 1958 #else 1959 static inline void task_numa_fault(int last_node, int node, int pages, 1960 int flags) 1961 { 1962 } 1963 static inline pid_t task_numa_group_id(struct task_struct *p) 1964 { 1965 return 0; 1966 } 1967 static inline void set_numabalancing_state(bool enabled) 1968 { 1969 } 1970 static inline void task_numa_free(struct task_struct *p) 1971 { 1972 } 1973 static inline bool should_numa_migrate_memory(struct task_struct *p, 1974 struct page *page, int src_nid, int dst_cpu) 1975 { 1976 return true; 1977 } 1978 #endif 1979 1980 static inline struct pid *task_pid(struct task_struct *task) 1981 { 1982 return task->pids[PIDTYPE_PID].pid; 1983 } 1984 1985 static inline struct pid *task_tgid(struct task_struct *task) 1986 { 1987 return task->group_leader->pids[PIDTYPE_PID].pid; 1988 } 1989 1990 /* 1991 * Without tasklist or rcu lock it is not safe to dereference 1992 * the result of task_pgrp/task_session even if task == current, 1993 * we can race with another thread doing sys_setsid/sys_setpgid. 1994 */ 1995 static inline struct pid *task_pgrp(struct task_struct *task) 1996 { 1997 return task->group_leader->pids[PIDTYPE_PGID].pid; 1998 } 1999 2000 static inline struct pid *task_session(struct task_struct *task) 2001 { 2002 return task->group_leader->pids[PIDTYPE_SID].pid; 2003 } 2004 2005 struct pid_namespace; 2006 2007 /* 2008 * the helpers to get the task's different pids as they are seen 2009 * from various namespaces 2010 * 2011 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 2012 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 2013 * current. 2014 * task_xid_nr_ns() : id seen from the ns specified; 2015 * 2016 * set_task_vxid() : assigns a virtual id to a task; 2017 * 2018 * see also pid_nr() etc in include/linux/pid.h 2019 */ 2020 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 2021 struct pid_namespace *ns); 2022 2023 static inline pid_t task_pid_nr(struct task_struct *tsk) 2024 { 2025 return tsk->pid; 2026 } 2027 2028 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 2029 struct pid_namespace *ns) 2030 { 2031 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 2032 } 2033 2034 static inline pid_t task_pid_vnr(struct task_struct *tsk) 2035 { 2036 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 2037 } 2038 2039 2040 static inline pid_t task_tgid_nr(struct task_struct *tsk) 2041 { 2042 return tsk->tgid; 2043 } 2044 2045 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 2046 2047 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 2048 { 2049 return pid_vnr(task_tgid(tsk)); 2050 } 2051 2052 2053 static inline int pid_alive(const struct task_struct *p); 2054 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 2055 { 2056 pid_t pid = 0; 2057 2058 rcu_read_lock(); 2059 if (pid_alive(tsk)) 2060 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 2061 rcu_read_unlock(); 2062 2063 return pid; 2064 } 2065 2066 static inline pid_t task_ppid_nr(const struct task_struct *tsk) 2067 { 2068 return task_ppid_nr_ns(tsk, &init_pid_ns); 2069 } 2070 2071 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 2072 struct pid_namespace *ns) 2073 { 2074 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 2075 } 2076 2077 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 2078 { 2079 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 2080 } 2081 2082 2083 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 2084 struct pid_namespace *ns) 2085 { 2086 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 2087 } 2088 2089 static inline pid_t task_session_vnr(struct task_struct *tsk) 2090 { 2091 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 2092 } 2093 2094 /* obsolete, do not use */ 2095 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 2096 { 2097 return task_pgrp_nr_ns(tsk, &init_pid_ns); 2098 } 2099 2100 /** 2101 * pid_alive - check that a task structure is not stale 2102 * @p: Task structure to be checked. 2103 * 2104 * Test if a process is not yet dead (at most zombie state) 2105 * If pid_alive fails, then pointers within the task structure 2106 * can be stale and must not be dereferenced. 2107 * 2108 * Return: 1 if the process is alive. 0 otherwise. 2109 */ 2110 static inline int pid_alive(const struct task_struct *p) 2111 { 2112 return p->pids[PIDTYPE_PID].pid != NULL; 2113 } 2114 2115 /** 2116 * is_global_init - check if a task structure is init. Since init 2117 * is free to have sub-threads we need to check tgid. 2118 * @tsk: Task structure to be checked. 2119 * 2120 * Check if a task structure is the first user space task the kernel created. 2121 * 2122 * Return: 1 if the task structure is init. 0 otherwise. 2123 */ 2124 static inline int is_global_init(struct task_struct *tsk) 2125 { 2126 return task_tgid_nr(tsk) == 1; 2127 } 2128 2129 extern struct pid *cad_pid; 2130 2131 extern void free_task(struct task_struct *tsk); 2132 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 2133 2134 extern void __put_task_struct(struct task_struct *t); 2135 2136 static inline void put_task_struct(struct task_struct *t) 2137 { 2138 if (atomic_dec_and_test(&t->usage)) 2139 __put_task_struct(t); 2140 } 2141 2142 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 2143 extern void task_cputime(struct task_struct *t, 2144 cputime_t *utime, cputime_t *stime); 2145 extern void task_cputime_scaled(struct task_struct *t, 2146 cputime_t *utimescaled, cputime_t *stimescaled); 2147 extern cputime_t task_gtime(struct task_struct *t); 2148 #else 2149 static inline void task_cputime(struct task_struct *t, 2150 cputime_t *utime, cputime_t *stime) 2151 { 2152 if (utime) 2153 *utime = t->utime; 2154 if (stime) 2155 *stime = t->stime; 2156 } 2157 2158 static inline void task_cputime_scaled(struct task_struct *t, 2159 cputime_t *utimescaled, 2160 cputime_t *stimescaled) 2161 { 2162 if (utimescaled) 2163 *utimescaled = t->utimescaled; 2164 if (stimescaled) 2165 *stimescaled = t->stimescaled; 2166 } 2167 2168 static inline cputime_t task_gtime(struct task_struct *t) 2169 { 2170 return t->gtime; 2171 } 2172 #endif 2173 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2174 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2175 2176 /* 2177 * Per process flags 2178 */ 2179 #define PF_EXITING 0x00000004 /* getting shut down */ 2180 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 2181 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 2182 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 2183 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 2184 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 2185 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 2186 #define PF_DUMPCORE 0x00000200 /* dumped core */ 2187 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 2188 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 2189 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 2190 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 2191 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 2192 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 2193 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 2194 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 2195 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 2196 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 2197 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 2198 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 2199 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 2200 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 2201 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 2202 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 2203 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 2204 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 2205 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 2206 2207 /* 2208 * Only the _current_ task can read/write to tsk->flags, but other 2209 * tasks can access tsk->flags in readonly mode for example 2210 * with tsk_used_math (like during threaded core dumping). 2211 * There is however an exception to this rule during ptrace 2212 * or during fork: the ptracer task is allowed to write to the 2213 * child->flags of its traced child (same goes for fork, the parent 2214 * can write to the child->flags), because we're guaranteed the 2215 * child is not running and in turn not changing child->flags 2216 * at the same time the parent does it. 2217 */ 2218 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 2219 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 2220 #define clear_used_math() clear_stopped_child_used_math(current) 2221 #define set_used_math() set_stopped_child_used_math(current) 2222 #define conditional_stopped_child_used_math(condition, child) \ 2223 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 2224 #define conditional_used_math(condition) \ 2225 conditional_stopped_child_used_math(condition, current) 2226 #define copy_to_stopped_child_used_math(child) \ 2227 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 2228 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 2229 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 2230 #define used_math() tsk_used_math(current) 2231 2232 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags 2233 * __GFP_FS is also cleared as it implies __GFP_IO. 2234 */ 2235 static inline gfp_t memalloc_noio_flags(gfp_t flags) 2236 { 2237 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 2238 flags &= ~(__GFP_IO | __GFP_FS); 2239 return flags; 2240 } 2241 2242 static inline unsigned int memalloc_noio_save(void) 2243 { 2244 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 2245 current->flags |= PF_MEMALLOC_NOIO; 2246 return flags; 2247 } 2248 2249 static inline void memalloc_noio_restore(unsigned int flags) 2250 { 2251 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 2252 } 2253 2254 /* Per-process atomic flags. */ 2255 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 2256 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 2257 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 2258 #define PFA_LMK_WAITING 3 /* Lowmemorykiller is waiting */ 2259 2260 2261 #define TASK_PFA_TEST(name, func) \ 2262 static inline bool task_##func(struct task_struct *p) \ 2263 { return test_bit(PFA_##name, &p->atomic_flags); } 2264 #define TASK_PFA_SET(name, func) \ 2265 static inline void task_set_##func(struct task_struct *p) \ 2266 { set_bit(PFA_##name, &p->atomic_flags); } 2267 #define TASK_PFA_CLEAR(name, func) \ 2268 static inline void task_clear_##func(struct task_struct *p) \ 2269 { clear_bit(PFA_##name, &p->atomic_flags); } 2270 2271 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 2272 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 2273 2274 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 2275 TASK_PFA_SET(SPREAD_PAGE, spread_page) 2276 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 2277 2278 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 2279 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 2280 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 2281 2282 TASK_PFA_TEST(LMK_WAITING, lmk_waiting) 2283 TASK_PFA_SET(LMK_WAITING, lmk_waiting) 2284 2285 /* 2286 * task->jobctl flags 2287 */ 2288 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 2289 2290 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 2291 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 2292 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 2293 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 2294 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 2295 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 2296 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 2297 2298 #define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT) 2299 #define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT) 2300 #define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT) 2301 #define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT) 2302 #define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT) 2303 #define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT) 2304 #define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT) 2305 2306 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 2307 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 2308 2309 extern bool task_set_jobctl_pending(struct task_struct *task, 2310 unsigned long mask); 2311 extern void task_clear_jobctl_trapping(struct task_struct *task); 2312 extern void task_clear_jobctl_pending(struct task_struct *task, 2313 unsigned long mask); 2314 2315 static inline void rcu_copy_process(struct task_struct *p) 2316 { 2317 #ifdef CONFIG_PREEMPT_RCU 2318 p->rcu_read_lock_nesting = 0; 2319 p->rcu_read_unlock_special.s = 0; 2320 p->rcu_blocked_node = NULL; 2321 INIT_LIST_HEAD(&p->rcu_node_entry); 2322 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 2323 #ifdef CONFIG_TASKS_RCU 2324 p->rcu_tasks_holdout = false; 2325 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); 2326 p->rcu_tasks_idle_cpu = -1; 2327 #endif /* #ifdef CONFIG_TASKS_RCU */ 2328 } 2329 2330 static inline void tsk_restore_flags(struct task_struct *task, 2331 unsigned long orig_flags, unsigned long flags) 2332 { 2333 task->flags &= ~flags; 2334 task->flags |= orig_flags & flags; 2335 } 2336 2337 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, 2338 const struct cpumask *trial); 2339 extern int task_can_attach(struct task_struct *p, 2340 const struct cpumask *cs_cpus_allowed); 2341 #ifdef CONFIG_SMP 2342 extern void do_set_cpus_allowed(struct task_struct *p, 2343 const struct cpumask *new_mask); 2344 2345 extern int set_cpus_allowed_ptr(struct task_struct *p, 2346 const struct cpumask *new_mask); 2347 #else 2348 static inline void do_set_cpus_allowed(struct task_struct *p, 2349 const struct cpumask *new_mask) 2350 { 2351 } 2352 static inline int set_cpus_allowed_ptr(struct task_struct *p, 2353 const struct cpumask *new_mask) 2354 { 2355 if (!cpumask_test_cpu(0, new_mask)) 2356 return -EINVAL; 2357 return 0; 2358 } 2359 #endif 2360 2361 #ifdef CONFIG_NO_HZ_COMMON 2362 void calc_load_enter_idle(void); 2363 void calc_load_exit_idle(void); 2364 #else 2365 static inline void calc_load_enter_idle(void) { } 2366 static inline void calc_load_exit_idle(void) { } 2367 #endif /* CONFIG_NO_HZ_COMMON */ 2368 2369 /* 2370 * Do not use outside of architecture code which knows its limitations. 2371 * 2372 * sched_clock() has no promise of monotonicity or bounded drift between 2373 * CPUs, use (which you should not) requires disabling IRQs. 2374 * 2375 * Please use one of the three interfaces below. 2376 */ 2377 extern unsigned long long notrace sched_clock(void); 2378 /* 2379 * See the comment in kernel/sched/clock.c 2380 */ 2381 extern u64 running_clock(void); 2382 extern u64 sched_clock_cpu(int cpu); 2383 2384 2385 extern void sched_clock_init(void); 2386 2387 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2388 static inline void sched_clock_tick(void) 2389 { 2390 } 2391 2392 static inline void sched_clock_idle_sleep_event(void) 2393 { 2394 } 2395 2396 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 2397 { 2398 } 2399 2400 static inline u64 cpu_clock(int cpu) 2401 { 2402 return sched_clock(); 2403 } 2404 2405 static inline u64 local_clock(void) 2406 { 2407 return sched_clock(); 2408 } 2409 #else 2410 /* 2411 * Architectures can set this to 1 if they have specified 2412 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 2413 * but then during bootup it turns out that sched_clock() 2414 * is reliable after all: 2415 */ 2416 extern int sched_clock_stable(void); 2417 extern void set_sched_clock_stable(void); 2418 extern void clear_sched_clock_stable(void); 2419 2420 extern void sched_clock_tick(void); 2421 extern void sched_clock_idle_sleep_event(void); 2422 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2423 2424 /* 2425 * As outlined in clock.c, provides a fast, high resolution, nanosecond 2426 * time source that is monotonic per cpu argument and has bounded drift 2427 * between cpus. 2428 * 2429 * ######################### BIG FAT WARNING ########################## 2430 * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can # 2431 * # go backwards !! # 2432 * #################################################################### 2433 */ 2434 static inline u64 cpu_clock(int cpu) 2435 { 2436 return sched_clock_cpu(cpu); 2437 } 2438 2439 static inline u64 local_clock(void) 2440 { 2441 return sched_clock_cpu(raw_smp_processor_id()); 2442 } 2443 #endif 2444 2445 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2446 /* 2447 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 2448 * The reason for this explicit opt-in is not to have perf penalty with 2449 * slow sched_clocks. 2450 */ 2451 extern void enable_sched_clock_irqtime(void); 2452 extern void disable_sched_clock_irqtime(void); 2453 #else 2454 static inline void enable_sched_clock_irqtime(void) {} 2455 static inline void disable_sched_clock_irqtime(void) {} 2456 #endif 2457 2458 extern unsigned long long 2459 task_sched_runtime(struct task_struct *task); 2460 2461 /* sched_exec is called by processes performing an exec */ 2462 #ifdef CONFIG_SMP 2463 extern void sched_exec(void); 2464 #else 2465 #define sched_exec() {} 2466 #endif 2467 2468 extern void sched_clock_idle_sleep_event(void); 2469 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2470 2471 #ifdef CONFIG_HOTPLUG_CPU 2472 extern void idle_task_exit(void); 2473 #else 2474 static inline void idle_task_exit(void) {} 2475 #endif 2476 2477 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 2478 extern void wake_up_nohz_cpu(int cpu); 2479 #else 2480 static inline void wake_up_nohz_cpu(int cpu) { } 2481 #endif 2482 2483 #ifdef CONFIG_NO_HZ_FULL 2484 extern u64 scheduler_tick_max_deferment(void); 2485 #endif 2486 2487 #ifdef CONFIG_SCHED_AUTOGROUP 2488 extern void sched_autogroup_create_attach(struct task_struct *p); 2489 extern void sched_autogroup_detach(struct task_struct *p); 2490 extern void sched_autogroup_fork(struct signal_struct *sig); 2491 extern void sched_autogroup_exit(struct signal_struct *sig); 2492 #ifdef CONFIG_PROC_FS 2493 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2494 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2495 #endif 2496 #else 2497 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2498 static inline void sched_autogroup_detach(struct task_struct *p) { } 2499 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2500 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2501 #endif 2502 2503 extern int yield_to(struct task_struct *p, bool preempt); 2504 extern void set_user_nice(struct task_struct *p, long nice); 2505 extern int task_prio(const struct task_struct *p); 2506 /** 2507 * task_nice - return the nice value of a given task. 2508 * @p: the task in question. 2509 * 2510 * Return: The nice value [ -20 ... 0 ... 19 ]. 2511 */ 2512 static inline int task_nice(const struct task_struct *p) 2513 { 2514 return PRIO_TO_NICE((p)->static_prio); 2515 } 2516 extern int can_nice(const struct task_struct *p, const int nice); 2517 extern int task_curr(const struct task_struct *p); 2518 extern int idle_cpu(int cpu); 2519 extern int sched_setscheduler(struct task_struct *, int, 2520 const struct sched_param *); 2521 extern int sched_setscheduler_nocheck(struct task_struct *, int, 2522 const struct sched_param *); 2523 extern int sched_setattr(struct task_struct *, 2524 const struct sched_attr *); 2525 extern struct task_struct *idle_task(int cpu); 2526 /** 2527 * is_idle_task - is the specified task an idle task? 2528 * @p: the task in question. 2529 * 2530 * Return: 1 if @p is an idle task. 0 otherwise. 2531 */ 2532 static inline bool is_idle_task(const struct task_struct *p) 2533 { 2534 return p->pid == 0; 2535 } 2536 extern struct task_struct *curr_task(int cpu); 2537 extern void set_curr_task(int cpu, struct task_struct *p); 2538 2539 void yield(void); 2540 2541 union thread_union { 2542 struct thread_info thread_info; 2543 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2544 }; 2545 2546 #ifndef __HAVE_ARCH_KSTACK_END 2547 static inline int kstack_end(void *addr) 2548 { 2549 /* Reliable end of stack detection: 2550 * Some APM bios versions misalign the stack 2551 */ 2552 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2553 } 2554 #endif 2555 2556 extern union thread_union init_thread_union; 2557 extern struct task_struct init_task; 2558 2559 extern struct mm_struct init_mm; 2560 2561 extern struct pid_namespace init_pid_ns; 2562 2563 /* 2564 * find a task by one of its numerical ids 2565 * 2566 * find_task_by_pid_ns(): 2567 * finds a task by its pid in the specified namespace 2568 * find_task_by_vpid(): 2569 * finds a task by its virtual pid 2570 * 2571 * see also find_vpid() etc in include/linux/pid.h 2572 */ 2573 2574 extern struct task_struct *find_task_by_vpid(pid_t nr); 2575 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2576 struct pid_namespace *ns); 2577 2578 /* per-UID process charging. */ 2579 extern struct user_struct * alloc_uid(kuid_t); 2580 static inline struct user_struct *get_uid(struct user_struct *u) 2581 { 2582 atomic_inc(&u->__count); 2583 return u; 2584 } 2585 extern void free_uid(struct user_struct *); 2586 2587 #include <asm/current.h> 2588 2589 extern void xtime_update(unsigned long ticks); 2590 2591 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2592 extern int wake_up_process(struct task_struct *tsk); 2593 extern void wake_up_new_task(struct task_struct *tsk); 2594 #ifdef CONFIG_SMP 2595 extern void kick_process(struct task_struct *tsk); 2596 #else 2597 static inline void kick_process(struct task_struct *tsk) { } 2598 #endif 2599 extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 2600 extern void sched_dead(struct task_struct *p); 2601 2602 extern void proc_caches_init(void); 2603 extern void flush_signals(struct task_struct *); 2604 extern void ignore_signals(struct task_struct *); 2605 extern void flush_signal_handlers(struct task_struct *, int force_default); 2606 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2607 2608 static inline int kernel_dequeue_signal(siginfo_t *info) 2609 { 2610 struct task_struct *tsk = current; 2611 siginfo_t __info; 2612 int ret; 2613 2614 spin_lock_irq(&tsk->sighand->siglock); 2615 ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info); 2616 spin_unlock_irq(&tsk->sighand->siglock); 2617 2618 return ret; 2619 } 2620 2621 static inline void kernel_signal_stop(void) 2622 { 2623 spin_lock_irq(¤t->sighand->siglock); 2624 if (current->jobctl & JOBCTL_STOP_DEQUEUED) 2625 __set_current_state(TASK_STOPPED); 2626 spin_unlock_irq(¤t->sighand->siglock); 2627 2628 schedule(); 2629 } 2630 2631 extern void release_task(struct task_struct * p); 2632 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2633 extern int force_sigsegv(int, struct task_struct *); 2634 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2635 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2636 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2637 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2638 const struct cred *, u32); 2639 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2640 extern int kill_pid(struct pid *pid, int sig, int priv); 2641 extern int kill_proc_info(int, struct siginfo *, pid_t); 2642 extern __must_check bool do_notify_parent(struct task_struct *, int); 2643 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2644 extern void force_sig(int, struct task_struct *); 2645 extern int send_sig(int, struct task_struct *, int); 2646 extern int zap_other_threads(struct task_struct *p); 2647 extern struct sigqueue *sigqueue_alloc(void); 2648 extern void sigqueue_free(struct sigqueue *); 2649 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2650 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2651 2652 static inline void restore_saved_sigmask(void) 2653 { 2654 if (test_and_clear_restore_sigmask()) 2655 __set_current_blocked(¤t->saved_sigmask); 2656 } 2657 2658 static inline sigset_t *sigmask_to_save(void) 2659 { 2660 sigset_t *res = ¤t->blocked; 2661 if (unlikely(test_restore_sigmask())) 2662 res = ¤t->saved_sigmask; 2663 return res; 2664 } 2665 2666 static inline int kill_cad_pid(int sig, int priv) 2667 { 2668 return kill_pid(cad_pid, sig, priv); 2669 } 2670 2671 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2672 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2673 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2674 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2675 2676 /* 2677 * True if we are on the alternate signal stack. 2678 */ 2679 static inline int on_sig_stack(unsigned long sp) 2680 { 2681 /* 2682 * If the signal stack is SS_AUTODISARM then, by construction, we 2683 * can't be on the signal stack unless user code deliberately set 2684 * SS_AUTODISARM when we were already on it. 2685 * 2686 * This improves reliability: if user state gets corrupted such that 2687 * the stack pointer points very close to the end of the signal stack, 2688 * then this check will enable the signal to be handled anyway. 2689 */ 2690 if (current->sas_ss_flags & SS_AUTODISARM) 2691 return 0; 2692 2693 #ifdef CONFIG_STACK_GROWSUP 2694 return sp >= current->sas_ss_sp && 2695 sp - current->sas_ss_sp < current->sas_ss_size; 2696 #else 2697 return sp > current->sas_ss_sp && 2698 sp - current->sas_ss_sp <= current->sas_ss_size; 2699 #endif 2700 } 2701 2702 static inline int sas_ss_flags(unsigned long sp) 2703 { 2704 if (!current->sas_ss_size) 2705 return SS_DISABLE; 2706 2707 return on_sig_stack(sp) ? SS_ONSTACK : 0; 2708 } 2709 2710 static inline void sas_ss_reset(struct task_struct *p) 2711 { 2712 p->sas_ss_sp = 0; 2713 p->sas_ss_size = 0; 2714 p->sas_ss_flags = SS_DISABLE; 2715 } 2716 2717 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2718 { 2719 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2720 #ifdef CONFIG_STACK_GROWSUP 2721 return current->sas_ss_sp; 2722 #else 2723 return current->sas_ss_sp + current->sas_ss_size; 2724 #endif 2725 return sp; 2726 } 2727 2728 /* 2729 * Routines for handling mm_structs 2730 */ 2731 extern struct mm_struct * mm_alloc(void); 2732 2733 /* mmdrop drops the mm and the page tables */ 2734 extern void __mmdrop(struct mm_struct *); 2735 static inline void mmdrop(struct mm_struct *mm) 2736 { 2737 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2738 __mmdrop(mm); 2739 } 2740 2741 static inline bool mmget_not_zero(struct mm_struct *mm) 2742 { 2743 return atomic_inc_not_zero(&mm->mm_users); 2744 } 2745 2746 /* mmput gets rid of the mappings and all user-space */ 2747 extern void mmput(struct mm_struct *); 2748 #ifdef CONFIG_MMU 2749 /* same as above but performs the slow path from the async context. Can 2750 * be called from the atomic context as well 2751 */ 2752 extern void mmput_async(struct mm_struct *); 2753 #endif 2754 2755 /* Grab a reference to a task's mm, if it is not already going away */ 2756 extern struct mm_struct *get_task_mm(struct task_struct *task); 2757 /* 2758 * Grab a reference to a task's mm, if it is not already going away 2759 * and ptrace_may_access with the mode parameter passed to it 2760 * succeeds. 2761 */ 2762 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2763 /* Remove the current tasks stale references to the old mm_struct */ 2764 extern void mm_release(struct task_struct *, struct mm_struct *); 2765 2766 #ifdef CONFIG_HAVE_COPY_THREAD_TLS 2767 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, 2768 struct task_struct *, unsigned long); 2769 #else 2770 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2771 struct task_struct *); 2772 2773 /* Architectures that haven't opted into copy_thread_tls get the tls argument 2774 * via pt_regs, so ignore the tls argument passed via C. */ 2775 static inline int copy_thread_tls( 2776 unsigned long clone_flags, unsigned long sp, unsigned long arg, 2777 struct task_struct *p, unsigned long tls) 2778 { 2779 return copy_thread(clone_flags, sp, arg, p); 2780 } 2781 #endif 2782 extern void flush_thread(void); 2783 2784 #ifdef CONFIG_HAVE_EXIT_THREAD 2785 extern void exit_thread(struct task_struct *tsk); 2786 #else 2787 static inline void exit_thread(struct task_struct *tsk) 2788 { 2789 } 2790 #endif 2791 2792 extern void exit_files(struct task_struct *); 2793 extern void __cleanup_sighand(struct sighand_struct *); 2794 2795 extern void exit_itimers(struct signal_struct *); 2796 extern void flush_itimer_signals(void); 2797 2798 extern void do_group_exit(int); 2799 2800 extern int do_execve(struct filename *, 2801 const char __user * const __user *, 2802 const char __user * const __user *); 2803 extern int do_execveat(int, struct filename *, 2804 const char __user * const __user *, 2805 const char __user * const __user *, 2806 int); 2807 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long); 2808 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2809 struct task_struct *fork_idle(int); 2810 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2811 2812 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 2813 static inline void set_task_comm(struct task_struct *tsk, const char *from) 2814 { 2815 __set_task_comm(tsk, from, false); 2816 } 2817 extern char *get_task_comm(char *to, struct task_struct *tsk); 2818 2819 #ifdef CONFIG_SMP 2820 void scheduler_ipi(void); 2821 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2822 #else 2823 static inline void scheduler_ipi(void) { } 2824 static inline unsigned long wait_task_inactive(struct task_struct *p, 2825 long match_state) 2826 { 2827 return 1; 2828 } 2829 #endif 2830 2831 #define tasklist_empty() \ 2832 list_empty(&init_task.tasks) 2833 2834 #define next_task(p) \ 2835 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2836 2837 #define for_each_process(p) \ 2838 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2839 2840 extern bool current_is_single_threaded(void); 2841 2842 /* 2843 * Careful: do_each_thread/while_each_thread is a double loop so 2844 * 'break' will not work as expected - use goto instead. 2845 */ 2846 #define do_each_thread(g, t) \ 2847 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 2848 2849 #define while_each_thread(g, t) \ 2850 while ((t = next_thread(t)) != g) 2851 2852 #define __for_each_thread(signal, t) \ 2853 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) 2854 2855 #define for_each_thread(p, t) \ 2856 __for_each_thread((p)->signal, t) 2857 2858 /* Careful: this is a double loop, 'break' won't work as expected. */ 2859 #define for_each_process_thread(p, t) \ 2860 for_each_process(p) for_each_thread(p, t) 2861 2862 static inline int get_nr_threads(struct task_struct *tsk) 2863 { 2864 return tsk->signal->nr_threads; 2865 } 2866 2867 static inline bool thread_group_leader(struct task_struct *p) 2868 { 2869 return p->exit_signal >= 0; 2870 } 2871 2872 /* Do to the insanities of de_thread it is possible for a process 2873 * to have the pid of the thread group leader without actually being 2874 * the thread group leader. For iteration through the pids in proc 2875 * all we care about is that we have a task with the appropriate 2876 * pid, we don't actually care if we have the right task. 2877 */ 2878 static inline bool has_group_leader_pid(struct task_struct *p) 2879 { 2880 return task_pid(p) == p->signal->leader_pid; 2881 } 2882 2883 static inline 2884 bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 2885 { 2886 return p1->signal == p2->signal; 2887 } 2888 2889 static inline struct task_struct *next_thread(const struct task_struct *p) 2890 { 2891 return list_entry_rcu(p->thread_group.next, 2892 struct task_struct, thread_group); 2893 } 2894 2895 static inline int thread_group_empty(struct task_struct *p) 2896 { 2897 return list_empty(&p->thread_group); 2898 } 2899 2900 #define delay_group_leader(p) \ 2901 (thread_group_leader(p) && !thread_group_empty(p)) 2902 2903 /* 2904 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 2905 * subscriptions and synchronises with wait4(). Also used in procfs. Also 2906 * pins the final release of task.io_context. Also protects ->cpuset and 2907 * ->cgroup.subsys[]. And ->vfork_done. 2908 * 2909 * Nests both inside and outside of read_lock(&tasklist_lock). 2910 * It must not be nested with write_lock_irq(&tasklist_lock), 2911 * neither inside nor outside. 2912 */ 2913 static inline void task_lock(struct task_struct *p) 2914 { 2915 spin_lock(&p->alloc_lock); 2916 } 2917 2918 static inline void task_unlock(struct task_struct *p) 2919 { 2920 spin_unlock(&p->alloc_lock); 2921 } 2922 2923 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 2924 unsigned long *flags); 2925 2926 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 2927 unsigned long *flags) 2928 { 2929 struct sighand_struct *ret; 2930 2931 ret = __lock_task_sighand(tsk, flags); 2932 (void)__cond_lock(&tsk->sighand->siglock, ret); 2933 return ret; 2934 } 2935 2936 static inline void unlock_task_sighand(struct task_struct *tsk, 2937 unsigned long *flags) 2938 { 2939 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 2940 } 2941 2942 /** 2943 * threadgroup_change_begin - mark the beginning of changes to a threadgroup 2944 * @tsk: task causing the changes 2945 * 2946 * All operations which modify a threadgroup - a new thread joining the 2947 * group, death of a member thread (the assertion of PF_EXITING) and 2948 * exec(2) dethreading the process and replacing the leader - are wrapped 2949 * by threadgroup_change_{begin|end}(). This is to provide a place which 2950 * subsystems needing threadgroup stability can hook into for 2951 * synchronization. 2952 */ 2953 static inline void threadgroup_change_begin(struct task_struct *tsk) 2954 { 2955 might_sleep(); 2956 cgroup_threadgroup_change_begin(tsk); 2957 } 2958 2959 /** 2960 * threadgroup_change_end - mark the end of changes to a threadgroup 2961 * @tsk: task causing the changes 2962 * 2963 * See threadgroup_change_begin(). 2964 */ 2965 static inline void threadgroup_change_end(struct task_struct *tsk) 2966 { 2967 cgroup_threadgroup_change_end(tsk); 2968 } 2969 2970 #ifndef __HAVE_THREAD_FUNCTIONS 2971 2972 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 2973 #define task_stack_page(task) ((task)->stack) 2974 2975 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 2976 { 2977 *task_thread_info(p) = *task_thread_info(org); 2978 task_thread_info(p)->task = p; 2979 } 2980 2981 /* 2982 * Return the address of the last usable long on the stack. 2983 * 2984 * When the stack grows down, this is just above the thread 2985 * info struct. Going any lower will corrupt the threadinfo. 2986 * 2987 * When the stack grows up, this is the highest address. 2988 * Beyond that position, we corrupt data on the next page. 2989 */ 2990 static inline unsigned long *end_of_stack(struct task_struct *p) 2991 { 2992 #ifdef CONFIG_STACK_GROWSUP 2993 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1; 2994 #else 2995 return (unsigned long *)(task_thread_info(p) + 1); 2996 #endif 2997 } 2998 2999 #endif 3000 #define task_stack_end_corrupted(task) \ 3001 (*(end_of_stack(task)) != STACK_END_MAGIC) 3002 3003 static inline int object_is_on_stack(void *obj) 3004 { 3005 void *stack = task_stack_page(current); 3006 3007 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 3008 } 3009 3010 extern void thread_stack_cache_init(void); 3011 3012 #ifdef CONFIG_DEBUG_STACK_USAGE 3013 static inline unsigned long stack_not_used(struct task_struct *p) 3014 { 3015 unsigned long *n = end_of_stack(p); 3016 3017 do { /* Skip over canary */ 3018 # ifdef CONFIG_STACK_GROWSUP 3019 n--; 3020 # else 3021 n++; 3022 # endif 3023 } while (!*n); 3024 3025 # ifdef CONFIG_STACK_GROWSUP 3026 return (unsigned long)end_of_stack(p) - (unsigned long)n; 3027 # else 3028 return (unsigned long)n - (unsigned long)end_of_stack(p); 3029 # endif 3030 } 3031 #endif 3032 extern void set_task_stack_end_magic(struct task_struct *tsk); 3033 3034 /* set thread flags in other task's structures 3035 * - see asm/thread_info.h for TIF_xxxx flags available 3036 */ 3037 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 3038 { 3039 set_ti_thread_flag(task_thread_info(tsk), flag); 3040 } 3041 3042 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 3043 { 3044 clear_ti_thread_flag(task_thread_info(tsk), flag); 3045 } 3046 3047 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 3048 { 3049 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 3050 } 3051 3052 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 3053 { 3054 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 3055 } 3056 3057 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 3058 { 3059 return test_ti_thread_flag(task_thread_info(tsk), flag); 3060 } 3061 3062 static inline void set_tsk_need_resched(struct task_struct *tsk) 3063 { 3064 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 3065 } 3066 3067 static inline void clear_tsk_need_resched(struct task_struct *tsk) 3068 { 3069 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 3070 } 3071 3072 static inline int test_tsk_need_resched(struct task_struct *tsk) 3073 { 3074 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 3075 } 3076 3077 static inline int restart_syscall(void) 3078 { 3079 set_tsk_thread_flag(current, TIF_SIGPENDING); 3080 return -ERESTARTNOINTR; 3081 } 3082 3083 static inline int signal_pending(struct task_struct *p) 3084 { 3085 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 3086 } 3087 3088 static inline int __fatal_signal_pending(struct task_struct *p) 3089 { 3090 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 3091 } 3092 3093 static inline int fatal_signal_pending(struct task_struct *p) 3094 { 3095 return signal_pending(p) && __fatal_signal_pending(p); 3096 } 3097 3098 static inline int signal_pending_state(long state, struct task_struct *p) 3099 { 3100 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 3101 return 0; 3102 if (!signal_pending(p)) 3103 return 0; 3104 3105 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 3106 } 3107 3108 /* 3109 * cond_resched() and cond_resched_lock(): latency reduction via 3110 * explicit rescheduling in places that are safe. The return 3111 * value indicates whether a reschedule was done in fact. 3112 * cond_resched_lock() will drop the spinlock before scheduling, 3113 * cond_resched_softirq() will enable bhs before scheduling. 3114 */ 3115 extern int _cond_resched(void); 3116 3117 #define cond_resched() ({ \ 3118 ___might_sleep(__FILE__, __LINE__, 0); \ 3119 _cond_resched(); \ 3120 }) 3121 3122 extern int __cond_resched_lock(spinlock_t *lock); 3123 3124 #define cond_resched_lock(lock) ({ \ 3125 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 3126 __cond_resched_lock(lock); \ 3127 }) 3128 3129 extern int __cond_resched_softirq(void); 3130 3131 #define cond_resched_softirq() ({ \ 3132 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 3133 __cond_resched_softirq(); \ 3134 }) 3135 3136 static inline void cond_resched_rcu(void) 3137 { 3138 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 3139 rcu_read_unlock(); 3140 cond_resched(); 3141 rcu_read_lock(); 3142 #endif 3143 } 3144 3145 /* 3146 * Does a critical section need to be broken due to another 3147 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 3148 * but a general need for low latency) 3149 */ 3150 static inline int spin_needbreak(spinlock_t *lock) 3151 { 3152 #ifdef CONFIG_PREEMPT 3153 return spin_is_contended(lock); 3154 #else 3155 return 0; 3156 #endif 3157 } 3158 3159 /* 3160 * Idle thread specific functions to determine the need_resched 3161 * polling state. 3162 */ 3163 #ifdef TIF_POLLING_NRFLAG 3164 static inline int tsk_is_polling(struct task_struct *p) 3165 { 3166 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 3167 } 3168 3169 static inline void __current_set_polling(void) 3170 { 3171 set_thread_flag(TIF_POLLING_NRFLAG); 3172 } 3173 3174 static inline bool __must_check current_set_polling_and_test(void) 3175 { 3176 __current_set_polling(); 3177 3178 /* 3179 * Polling state must be visible before we test NEED_RESCHED, 3180 * paired by resched_curr() 3181 */ 3182 smp_mb__after_atomic(); 3183 3184 return unlikely(tif_need_resched()); 3185 } 3186 3187 static inline void __current_clr_polling(void) 3188 { 3189 clear_thread_flag(TIF_POLLING_NRFLAG); 3190 } 3191 3192 static inline bool __must_check current_clr_polling_and_test(void) 3193 { 3194 __current_clr_polling(); 3195 3196 /* 3197 * Polling state must be visible before we test NEED_RESCHED, 3198 * paired by resched_curr() 3199 */ 3200 smp_mb__after_atomic(); 3201 3202 return unlikely(tif_need_resched()); 3203 } 3204 3205 #else 3206 static inline int tsk_is_polling(struct task_struct *p) { return 0; } 3207 static inline void __current_set_polling(void) { } 3208 static inline void __current_clr_polling(void) { } 3209 3210 static inline bool __must_check current_set_polling_and_test(void) 3211 { 3212 return unlikely(tif_need_resched()); 3213 } 3214 static inline bool __must_check current_clr_polling_and_test(void) 3215 { 3216 return unlikely(tif_need_resched()); 3217 } 3218 #endif 3219 3220 static inline void current_clr_polling(void) 3221 { 3222 __current_clr_polling(); 3223 3224 /* 3225 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit. 3226 * Once the bit is cleared, we'll get IPIs with every new 3227 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also 3228 * fold. 3229 */ 3230 smp_mb(); /* paired with resched_curr() */ 3231 3232 preempt_fold_need_resched(); 3233 } 3234 3235 static __always_inline bool need_resched(void) 3236 { 3237 return unlikely(tif_need_resched()); 3238 } 3239 3240 /* 3241 * Thread group CPU time accounting. 3242 */ 3243 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 3244 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 3245 3246 /* 3247 * Reevaluate whether the task has signals pending delivery. 3248 * Wake the task if so. 3249 * This is required every time the blocked sigset_t changes. 3250 * callers must hold sighand->siglock. 3251 */ 3252 extern void recalc_sigpending_and_wake(struct task_struct *t); 3253 extern void recalc_sigpending(void); 3254 3255 extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 3256 3257 static inline void signal_wake_up(struct task_struct *t, bool resume) 3258 { 3259 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 3260 } 3261 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 3262 { 3263 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 3264 } 3265 3266 /* 3267 * Wrappers for p->thread_info->cpu access. No-op on UP. 3268 */ 3269 #ifdef CONFIG_SMP 3270 3271 static inline unsigned int task_cpu(const struct task_struct *p) 3272 { 3273 return task_thread_info(p)->cpu; 3274 } 3275 3276 static inline int task_node(const struct task_struct *p) 3277 { 3278 return cpu_to_node(task_cpu(p)); 3279 } 3280 3281 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 3282 3283 #else 3284 3285 static inline unsigned int task_cpu(const struct task_struct *p) 3286 { 3287 return 0; 3288 } 3289 3290 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 3291 { 3292 } 3293 3294 #endif /* CONFIG_SMP */ 3295 3296 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 3297 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 3298 3299 #ifdef CONFIG_CGROUP_SCHED 3300 extern struct task_group root_task_group; 3301 #endif /* CONFIG_CGROUP_SCHED */ 3302 3303 extern int task_can_switch_user(struct user_struct *up, 3304 struct task_struct *tsk); 3305 3306 #ifdef CONFIG_TASK_XACCT 3307 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3308 { 3309 tsk->ioac.rchar += amt; 3310 } 3311 3312 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3313 { 3314 tsk->ioac.wchar += amt; 3315 } 3316 3317 static inline void inc_syscr(struct task_struct *tsk) 3318 { 3319 tsk->ioac.syscr++; 3320 } 3321 3322 static inline void inc_syscw(struct task_struct *tsk) 3323 { 3324 tsk->ioac.syscw++; 3325 } 3326 #else 3327 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3328 { 3329 } 3330 3331 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3332 { 3333 } 3334 3335 static inline void inc_syscr(struct task_struct *tsk) 3336 { 3337 } 3338 3339 static inline void inc_syscw(struct task_struct *tsk) 3340 { 3341 } 3342 #endif 3343 3344 #ifndef TASK_SIZE_OF 3345 #define TASK_SIZE_OF(tsk) TASK_SIZE 3346 #endif 3347 3348 #ifdef CONFIG_MEMCG 3349 extern void mm_update_next_owner(struct mm_struct *mm); 3350 #else 3351 static inline void mm_update_next_owner(struct mm_struct *mm) 3352 { 3353 } 3354 #endif /* CONFIG_MEMCG */ 3355 3356 static inline unsigned long task_rlimit(const struct task_struct *tsk, 3357 unsigned int limit) 3358 { 3359 return READ_ONCE(tsk->signal->rlim[limit].rlim_cur); 3360 } 3361 3362 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 3363 unsigned int limit) 3364 { 3365 return READ_ONCE(tsk->signal->rlim[limit].rlim_max); 3366 } 3367 3368 static inline unsigned long rlimit(unsigned int limit) 3369 { 3370 return task_rlimit(current, limit); 3371 } 3372 3373 static inline unsigned long rlimit_max(unsigned int limit) 3374 { 3375 return task_rlimit_max(current, limit); 3376 } 3377 3378 #ifdef CONFIG_CPU_FREQ 3379 struct update_util_data { 3380 void (*func)(struct update_util_data *data, 3381 u64 time, unsigned long util, unsigned long max); 3382 }; 3383 3384 void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data, 3385 void (*func)(struct update_util_data *data, u64 time, 3386 unsigned long util, unsigned long max)); 3387 void cpufreq_remove_update_util_hook(int cpu); 3388 #endif /* CONFIG_CPU_FREQ */ 3389 3390 #endif 3391