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 33 #include <linux/smp.h> 34 #include <linux/sem.h> 35 #include <linux/shm.h> 36 #include <linux/signal.h> 37 #include <linux/compiler.h> 38 #include <linux/completion.h> 39 #include <linux/pid.h> 40 #include <linux/percpu.h> 41 #include <linux/topology.h> 42 #include <linux/seccomp.h> 43 #include <linux/rcupdate.h> 44 #include <linux/rculist.h> 45 #include <linux/rtmutex.h> 46 47 #include <linux/time.h> 48 #include <linux/param.h> 49 #include <linux/resource.h> 50 #include <linux/timer.h> 51 #include <linux/hrtimer.h> 52 #include <linux/kcov.h> 53 #include <linux/task_io_accounting.h> 54 #include <linux/latencytop.h> 55 #include <linux/cred.h> 56 #include <linux/llist.h> 57 #include <linux/uidgid.h> 58 #include <linux/gfp.h> 59 #include <linux/magic.h> 60 #include <linux/cgroup-defs.h> 61 62 #include <asm/processor.h> 63 64 #define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */ 65 66 /* 67 * Extended scheduling parameters data structure. 68 * 69 * This is needed because the original struct sched_param can not be 70 * altered without introducing ABI issues with legacy applications 71 * (e.g., in sched_getparam()). 72 * 73 * However, the possibility of specifying more than just a priority for 74 * the tasks may be useful for a wide variety of application fields, e.g., 75 * multimedia, streaming, automation and control, and many others. 76 * 77 * This variant (sched_attr) is meant at describing a so-called 78 * sporadic time-constrained task. In such model a task is specified by: 79 * - the activation period or minimum instance inter-arrival time; 80 * - the maximum (or average, depending on the actual scheduling 81 * discipline) computation time of all instances, a.k.a. runtime; 82 * - the deadline (relative to the actual activation time) of each 83 * instance. 84 * Very briefly, a periodic (sporadic) task asks for the execution of 85 * some specific computation --which is typically called an instance-- 86 * (at most) every period. Moreover, each instance typically lasts no more 87 * than the runtime and must be completed by time instant t equal to 88 * the instance activation time + the deadline. 89 * 90 * This is reflected by the actual fields of the sched_attr structure: 91 * 92 * @size size of the structure, for fwd/bwd compat. 93 * 94 * @sched_policy task's scheduling policy 95 * @sched_flags for customizing the scheduler behaviour 96 * @sched_nice task's nice value (SCHED_NORMAL/BATCH) 97 * @sched_priority task's static priority (SCHED_FIFO/RR) 98 * @sched_deadline representative of the task's deadline 99 * @sched_runtime representative of the task's runtime 100 * @sched_period representative of the task's period 101 * 102 * Given this task model, there are a multiplicity of scheduling algorithms 103 * and policies, that can be used to ensure all the tasks will make their 104 * timing constraints. 105 * 106 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the 107 * only user of this new interface. More information about the algorithm 108 * available in the scheduling class file or in Documentation/. 109 */ 110 struct sched_attr { 111 u32 size; 112 113 u32 sched_policy; 114 u64 sched_flags; 115 116 /* SCHED_NORMAL, SCHED_BATCH */ 117 s32 sched_nice; 118 119 /* SCHED_FIFO, SCHED_RR */ 120 u32 sched_priority; 121 122 /* SCHED_DEADLINE */ 123 u64 sched_runtime; 124 u64 sched_deadline; 125 u64 sched_period; 126 }; 127 128 struct futex_pi_state; 129 struct robust_list_head; 130 struct bio_list; 131 struct fs_struct; 132 struct perf_event_context; 133 struct blk_plug; 134 struct filename; 135 struct nameidata; 136 137 #define VMACACHE_BITS 2 138 #define VMACACHE_SIZE (1U << VMACACHE_BITS) 139 #define VMACACHE_MASK (VMACACHE_SIZE - 1) 140 141 /* 142 * These are the constant used to fake the fixed-point load-average 143 * counting. Some notes: 144 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 145 * a load-average precision of 10 bits integer + 11 bits fractional 146 * - if you want to count load-averages more often, you need more 147 * precision, or rounding will get you. With 2-second counting freq, 148 * the EXP_n values would be 1981, 2034 and 2043 if still using only 149 * 11 bit fractions. 150 */ 151 extern unsigned long avenrun[]; /* Load averages */ 152 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 153 154 #define FSHIFT 11 /* nr of bits of precision */ 155 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 156 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 157 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 158 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 159 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 160 161 #define CALC_LOAD(load,exp,n) \ 162 load *= exp; \ 163 load += n*(FIXED_1-exp); \ 164 load >>= FSHIFT; 165 166 extern unsigned long total_forks; 167 extern int nr_threads; 168 DECLARE_PER_CPU(unsigned long, process_counts); 169 extern int nr_processes(void); 170 extern unsigned long nr_running(void); 171 extern bool single_task_running(void); 172 extern unsigned long nr_iowait(void); 173 extern unsigned long nr_iowait_cpu(int cpu); 174 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load); 175 176 extern void calc_global_load(unsigned long ticks); 177 178 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 179 extern void cpu_load_update_nohz_start(void); 180 extern void cpu_load_update_nohz_stop(void); 181 #else 182 static inline void cpu_load_update_nohz_start(void) { } 183 static inline void cpu_load_update_nohz_stop(void) { } 184 #endif 185 186 extern void dump_cpu_task(int cpu); 187 188 struct seq_file; 189 struct cfs_rq; 190 struct task_group; 191 #ifdef CONFIG_SCHED_DEBUG 192 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 193 extern void proc_sched_set_task(struct task_struct *p); 194 #endif 195 196 /* 197 * Task state bitmask. NOTE! These bits are also 198 * encoded in fs/proc/array.c: get_task_state(). 199 * 200 * We have two separate sets of flags: task->state 201 * is about runnability, while task->exit_state are 202 * about the task exiting. Confusing, but this way 203 * modifying one set can't modify the other one by 204 * mistake. 205 */ 206 #define TASK_RUNNING 0 207 #define TASK_INTERRUPTIBLE 1 208 #define TASK_UNINTERRUPTIBLE 2 209 #define __TASK_STOPPED 4 210 #define __TASK_TRACED 8 211 /* in tsk->exit_state */ 212 #define EXIT_DEAD 16 213 #define EXIT_ZOMBIE 32 214 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 215 /* in tsk->state again */ 216 #define TASK_DEAD 64 217 #define TASK_WAKEKILL 128 218 #define TASK_WAKING 256 219 #define TASK_PARKED 512 220 #define TASK_NOLOAD 1024 221 #define TASK_NEW 2048 222 #define TASK_STATE_MAX 4096 223 224 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPNn" 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_current_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_current_state(state_value) \ 257 do { \ 258 current->task_state_change = _THIS_IP_; \ 259 current->state = (state_value); \ 260 } while (0) 261 #define set_current_state(state_value) \ 262 do { \ 263 current->task_state_change = _THIS_IP_; \ 264 smp_store_mb(current->state, (state_value)); \ 265 } while (0) 266 267 #else 268 /* 269 * set_current_state() includes a barrier so that the write of current->state 270 * is correctly serialised wrt the caller's subsequent test of whether to 271 * actually sleep: 272 * 273 * for (;;) { 274 * set_current_state(TASK_UNINTERRUPTIBLE); 275 * if (!need_sleep) 276 * break; 277 * 278 * schedule(); 279 * } 280 * __set_current_state(TASK_RUNNING); 281 * 282 * If the caller does not need such serialisation (because, for instance, the 283 * condition test and condition change and wakeup are under the same lock) then 284 * use __set_current_state(). 285 * 286 * The above is typically ordered against the wakeup, which does: 287 * 288 * need_sleep = false; 289 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 290 * 291 * Where wake_up_state() (and all other wakeup primitives) imply enough 292 * barriers to order the store of the variable against wakeup. 293 * 294 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is, 295 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 296 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 297 * 298 * This is obviously fine, since they both store the exact same value. 299 * 300 * Also see the comments of try_to_wake_up(). 301 */ 302 #define __set_current_state(state_value) \ 303 do { current->state = (state_value); } while (0) 304 #define set_current_state(state_value) \ 305 smp_store_mb(current->state, (state_value)) 306 307 #endif 308 309 /* Task command name length */ 310 #define TASK_COMM_LEN 16 311 312 #include <linux/spinlock.h> 313 314 /* 315 * This serializes "schedule()" and also protects 316 * the run-queue from deletions/modifications (but 317 * _adding_ to the beginning of the run-queue has 318 * a separate lock). 319 */ 320 extern rwlock_t tasklist_lock; 321 extern spinlock_t mmlist_lock; 322 323 struct task_struct; 324 325 #ifdef CONFIG_PROVE_RCU 326 extern int lockdep_tasklist_lock_is_held(void); 327 #endif /* #ifdef CONFIG_PROVE_RCU */ 328 329 extern void sched_init(void); 330 extern void sched_init_smp(void); 331 extern asmlinkage void schedule_tail(struct task_struct *prev); 332 extern void init_idle(struct task_struct *idle, int cpu); 333 extern void init_idle_bootup_task(struct task_struct *idle); 334 335 extern cpumask_var_t cpu_isolated_map; 336 337 extern int runqueue_is_locked(int cpu); 338 339 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 340 extern void nohz_balance_enter_idle(int cpu); 341 extern void set_cpu_sd_state_idle(void); 342 extern int get_nohz_timer_target(void); 343 #else 344 static inline void nohz_balance_enter_idle(int cpu) { } 345 static inline void set_cpu_sd_state_idle(void) { } 346 #endif 347 348 /* 349 * Only dump TASK_* tasks. (0 for all tasks) 350 */ 351 extern void show_state_filter(unsigned long state_filter); 352 353 static inline void show_state(void) 354 { 355 show_state_filter(0); 356 } 357 358 extern void show_regs(struct pt_regs *); 359 360 /* 361 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 362 * task), SP is the stack pointer of the first frame that should be shown in the back 363 * trace (or NULL if the entire call-chain of the task should be shown). 364 */ 365 extern void show_stack(struct task_struct *task, unsigned long *sp); 366 367 extern void cpu_init (void); 368 extern void trap_init(void); 369 extern void update_process_times(int user); 370 extern void scheduler_tick(void); 371 extern int sched_cpu_starting(unsigned int cpu); 372 extern int sched_cpu_activate(unsigned int cpu); 373 extern int sched_cpu_deactivate(unsigned int cpu); 374 375 #ifdef CONFIG_HOTPLUG_CPU 376 extern int sched_cpu_dying(unsigned int cpu); 377 #else 378 # define sched_cpu_dying NULL 379 #endif 380 381 extern void sched_show_task(struct task_struct *p); 382 383 #ifdef CONFIG_LOCKUP_DETECTOR 384 extern void touch_softlockup_watchdog_sched(void); 385 extern void touch_softlockup_watchdog(void); 386 extern void touch_softlockup_watchdog_sync(void); 387 extern void touch_all_softlockup_watchdogs(void); 388 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 389 void __user *buffer, 390 size_t *lenp, loff_t *ppos); 391 extern unsigned int softlockup_panic; 392 extern unsigned int hardlockup_panic; 393 void lockup_detector_init(void); 394 #else 395 static inline void touch_softlockup_watchdog_sched(void) 396 { 397 } 398 static inline void touch_softlockup_watchdog(void) 399 { 400 } 401 static inline void touch_softlockup_watchdog_sync(void) 402 { 403 } 404 static inline void touch_all_softlockup_watchdogs(void) 405 { 406 } 407 static inline void lockup_detector_init(void) 408 { 409 } 410 #endif 411 412 #ifdef CONFIG_DETECT_HUNG_TASK 413 void reset_hung_task_detector(void); 414 #else 415 static inline void reset_hung_task_detector(void) 416 { 417 } 418 #endif 419 420 /* Attach to any functions which should be ignored in wchan output. */ 421 #define __sched __attribute__((__section__(".sched.text"))) 422 423 /* Linker adds these: start and end of __sched functions */ 424 extern char __sched_text_start[], __sched_text_end[]; 425 426 /* Is this address in the __sched functions? */ 427 extern int in_sched_functions(unsigned long addr); 428 429 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 430 extern signed long schedule_timeout(signed long timeout); 431 extern signed long schedule_timeout_interruptible(signed long timeout); 432 extern signed long schedule_timeout_killable(signed long timeout); 433 extern signed long schedule_timeout_uninterruptible(signed long timeout); 434 extern signed long schedule_timeout_idle(signed long timeout); 435 asmlinkage void schedule(void); 436 extern void schedule_preempt_disabled(void); 437 438 extern int __must_check io_schedule_prepare(void); 439 extern void io_schedule_finish(int token); 440 extern long io_schedule_timeout(long timeout); 441 extern void io_schedule(void); 442 443 void __noreturn do_task_dead(void); 444 445 struct nsproxy; 446 struct user_namespace; 447 448 #ifdef CONFIG_MMU 449 extern void arch_pick_mmap_layout(struct mm_struct *mm); 450 extern unsigned long 451 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 452 unsigned long, unsigned long); 453 extern unsigned long 454 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 455 unsigned long len, unsigned long pgoff, 456 unsigned long flags); 457 #else 458 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 459 #endif 460 461 #define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 462 #define SUID_DUMP_USER 1 /* Dump as user of process */ 463 #define SUID_DUMP_ROOT 2 /* Dump as root */ 464 465 /* mm flags */ 466 467 /* for SUID_DUMP_* above */ 468 #define MMF_DUMPABLE_BITS 2 469 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 470 471 extern void set_dumpable(struct mm_struct *mm, int value); 472 /* 473 * This returns the actual value of the suid_dumpable flag. For things 474 * that are using this for checking for privilege transitions, it must 475 * test against SUID_DUMP_USER rather than treating it as a boolean 476 * value. 477 */ 478 static inline int __get_dumpable(unsigned long mm_flags) 479 { 480 return mm_flags & MMF_DUMPABLE_MASK; 481 } 482 483 static inline int get_dumpable(struct mm_struct *mm) 484 { 485 return __get_dumpable(mm->flags); 486 } 487 488 /* coredump filter bits */ 489 #define MMF_DUMP_ANON_PRIVATE 2 490 #define MMF_DUMP_ANON_SHARED 3 491 #define MMF_DUMP_MAPPED_PRIVATE 4 492 #define MMF_DUMP_MAPPED_SHARED 5 493 #define MMF_DUMP_ELF_HEADERS 6 494 #define MMF_DUMP_HUGETLB_PRIVATE 7 495 #define MMF_DUMP_HUGETLB_SHARED 8 496 #define MMF_DUMP_DAX_PRIVATE 9 497 #define MMF_DUMP_DAX_SHARED 10 498 499 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 500 #define MMF_DUMP_FILTER_BITS 9 501 #define MMF_DUMP_FILTER_MASK \ 502 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 503 #define MMF_DUMP_FILTER_DEFAULT \ 504 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 505 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 506 507 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 508 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 509 #else 510 # define MMF_DUMP_MASK_DEFAULT_ELF 0 511 #endif 512 /* leave room for more dump flags */ 513 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 514 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 515 /* 516 * This one-shot flag is dropped due to necessity of changing exe once again 517 * on NFS restore 518 */ 519 //#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 520 521 #define MMF_HAS_UPROBES 19 /* has uprobes */ 522 #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 523 #define MMF_OOM_SKIP 21 /* mm is of no interest for the OOM killer */ 524 #define MMF_UNSTABLE 22 /* mm is unstable for copy_from_user */ 525 #define MMF_HUGE_ZERO_PAGE 23 /* mm has ever used the global huge zero page */ 526 527 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 528 529 struct sighand_struct { 530 atomic_t count; 531 struct k_sigaction action[_NSIG]; 532 spinlock_t siglock; 533 wait_queue_head_t signalfd_wqh; 534 }; 535 536 struct pacct_struct { 537 int ac_flag; 538 long ac_exitcode; 539 unsigned long ac_mem; 540 u64 ac_utime, ac_stime; 541 unsigned long ac_minflt, ac_majflt; 542 }; 543 544 struct cpu_itimer { 545 u64 expires; 546 u64 incr; 547 }; 548 549 /** 550 * struct prev_cputime - snaphsot of system and user cputime 551 * @utime: time spent in user mode 552 * @stime: time spent in system mode 553 * @lock: protects the above two fields 554 * 555 * Stores previous user/system time values such that we can guarantee 556 * monotonicity. 557 */ 558 struct prev_cputime { 559 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 560 u64 utime; 561 u64 stime; 562 raw_spinlock_t lock; 563 #endif 564 }; 565 566 static inline void prev_cputime_init(struct prev_cputime *prev) 567 { 568 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 569 prev->utime = prev->stime = 0; 570 raw_spin_lock_init(&prev->lock); 571 #endif 572 } 573 574 /** 575 * struct task_cputime - collected CPU time counts 576 * @utime: time spent in user mode, in nanoseconds 577 * @stime: time spent in kernel mode, in nanoseconds 578 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 579 * 580 * This structure groups together three kinds of CPU time that are tracked for 581 * threads and thread groups. Most things considering CPU time want to group 582 * these counts together and treat all three of them in parallel. 583 */ 584 struct task_cputime { 585 u64 utime; 586 u64 stime; 587 unsigned long long sum_exec_runtime; 588 }; 589 590 /* Alternate field names when used to cache expirations. */ 591 #define virt_exp utime 592 #define prof_exp stime 593 #define sched_exp sum_exec_runtime 594 595 /* 596 * This is the atomic variant of task_cputime, which can be used for 597 * storing and updating task_cputime statistics without locking. 598 */ 599 struct task_cputime_atomic { 600 atomic64_t utime; 601 atomic64_t stime; 602 atomic64_t sum_exec_runtime; 603 }; 604 605 #define INIT_CPUTIME_ATOMIC \ 606 (struct task_cputime_atomic) { \ 607 .utime = ATOMIC64_INIT(0), \ 608 .stime = ATOMIC64_INIT(0), \ 609 .sum_exec_runtime = ATOMIC64_INIT(0), \ 610 } 611 612 #define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) 613 614 /* 615 * Disable preemption until the scheduler is running -- use an unconditional 616 * value so that it also works on !PREEMPT_COUNT kernels. 617 * 618 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count(). 619 */ 620 #define INIT_PREEMPT_COUNT PREEMPT_OFFSET 621 622 /* 623 * Initial preempt_count value; reflects the preempt_count schedule invariant 624 * which states that during context switches: 625 * 626 * preempt_count() == 2*PREEMPT_DISABLE_OFFSET 627 * 628 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels. 629 * Note: See finish_task_switch(). 630 */ 631 #define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) 632 633 /** 634 * struct thread_group_cputimer - thread group interval timer counts 635 * @cputime_atomic: atomic thread group interval timers. 636 * @running: true when there are timers running and 637 * @cputime_atomic receives updates. 638 * @checking_timer: true when a thread in the group is in the 639 * process of checking for thread group timers. 640 * 641 * This structure contains the version of task_cputime, above, that is 642 * used for thread group CPU timer calculations. 643 */ 644 struct thread_group_cputimer { 645 struct task_cputime_atomic cputime_atomic; 646 bool running; 647 bool checking_timer; 648 }; 649 650 #include <linux/rwsem.h> 651 struct autogroup; 652 653 /* 654 * NOTE! "signal_struct" does not have its own 655 * locking, because a shared signal_struct always 656 * implies a shared sighand_struct, so locking 657 * sighand_struct is always a proper superset of 658 * the locking of signal_struct. 659 */ 660 struct signal_struct { 661 atomic_t sigcnt; 662 atomic_t live; 663 int nr_threads; 664 struct list_head thread_head; 665 666 wait_queue_head_t wait_chldexit; /* for wait4() */ 667 668 /* current thread group signal load-balancing target: */ 669 struct task_struct *curr_target; 670 671 /* shared signal handling: */ 672 struct sigpending shared_pending; 673 674 /* thread group exit support */ 675 int group_exit_code; 676 /* overloaded: 677 * - notify group_exit_task when ->count is equal to notify_count 678 * - everyone except group_exit_task is stopped during signal delivery 679 * of fatal signals, group_exit_task processes the signal. 680 */ 681 int notify_count; 682 struct task_struct *group_exit_task; 683 684 /* thread group stop support, overloads group_exit_code too */ 685 int group_stop_count; 686 unsigned int flags; /* see SIGNAL_* flags below */ 687 688 /* 689 * PR_SET_CHILD_SUBREAPER marks a process, like a service 690 * manager, to re-parent orphan (double-forking) child processes 691 * to this process instead of 'init'. The service manager is 692 * able to receive SIGCHLD signals and is able to investigate 693 * the process until it calls wait(). All children of this 694 * process will inherit a flag if they should look for a 695 * child_subreaper process at exit. 696 */ 697 unsigned int is_child_subreaper:1; 698 unsigned int has_child_subreaper:1; 699 700 #ifdef CONFIG_POSIX_TIMERS 701 702 /* POSIX.1b Interval Timers */ 703 int posix_timer_id; 704 struct list_head posix_timers; 705 706 /* ITIMER_REAL timer for the process */ 707 struct hrtimer real_timer; 708 ktime_t it_real_incr; 709 710 /* 711 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 712 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 713 * values are defined to 0 and 1 respectively 714 */ 715 struct cpu_itimer it[2]; 716 717 /* 718 * Thread group totals for process CPU timers. 719 * See thread_group_cputimer(), et al, for details. 720 */ 721 struct thread_group_cputimer cputimer; 722 723 /* Earliest-expiration cache. */ 724 struct task_cputime cputime_expires; 725 726 struct list_head cpu_timers[3]; 727 728 #endif 729 730 struct pid *leader_pid; 731 732 #ifdef CONFIG_NO_HZ_FULL 733 atomic_t tick_dep_mask; 734 #endif 735 736 struct pid *tty_old_pgrp; 737 738 /* boolean value for session group leader */ 739 int leader; 740 741 struct tty_struct *tty; /* NULL if no tty */ 742 743 #ifdef CONFIG_SCHED_AUTOGROUP 744 struct autogroup *autogroup; 745 #endif 746 /* 747 * Cumulative resource counters for dead threads in the group, 748 * and for reaped dead child processes forked by this group. 749 * Live threads maintain their own counters and add to these 750 * in __exit_signal, except for the group leader. 751 */ 752 seqlock_t stats_lock; 753 u64 utime, stime, cutime, cstime; 754 u64 gtime; 755 u64 cgtime; 756 struct prev_cputime prev_cputime; 757 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 758 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 759 unsigned long inblock, oublock, cinblock, coublock; 760 unsigned long maxrss, cmaxrss; 761 struct task_io_accounting ioac; 762 763 /* 764 * Cumulative ns of schedule CPU time fo dead threads in the 765 * group, not including a zombie group leader, (This only differs 766 * from jiffies_to_ns(utime + stime) if sched_clock uses something 767 * other than jiffies.) 768 */ 769 unsigned long long sum_sched_runtime; 770 771 /* 772 * We don't bother to synchronize most readers of this at all, 773 * because there is no reader checking a limit that actually needs 774 * to get both rlim_cur and rlim_max atomically, and either one 775 * alone is a single word that can safely be read normally. 776 * getrlimit/setrlimit use task_lock(current->group_leader) to 777 * protect this instead of the siglock, because they really 778 * have no need to disable irqs. 779 */ 780 struct rlimit rlim[RLIM_NLIMITS]; 781 782 #ifdef CONFIG_BSD_PROCESS_ACCT 783 struct pacct_struct pacct; /* per-process accounting information */ 784 #endif 785 #ifdef CONFIG_TASKSTATS 786 struct taskstats *stats; 787 #endif 788 #ifdef CONFIG_AUDIT 789 unsigned audit_tty; 790 struct tty_audit_buf *tty_audit_buf; 791 #endif 792 793 /* 794 * Thread is the potential origin of an oom condition; kill first on 795 * oom 796 */ 797 bool oom_flag_origin; 798 short oom_score_adj; /* OOM kill score adjustment */ 799 short oom_score_adj_min; /* OOM kill score adjustment min value. 800 * Only settable by CAP_SYS_RESOURCE. */ 801 struct mm_struct *oom_mm; /* recorded mm when the thread group got 802 * killed by the oom killer */ 803 804 struct mutex cred_guard_mutex; /* guard against foreign influences on 805 * credential calculations 806 * (notably. ptrace) */ 807 }; 808 809 /* 810 * Bits in flags field of signal_struct. 811 */ 812 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 813 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 814 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 815 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 816 /* 817 * Pending notifications to parent. 818 */ 819 #define SIGNAL_CLD_STOPPED 0x00000010 820 #define SIGNAL_CLD_CONTINUED 0x00000020 821 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 822 823 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 824 825 #define SIGNAL_STOP_MASK (SIGNAL_CLD_MASK | SIGNAL_STOP_STOPPED | \ 826 SIGNAL_STOP_CONTINUED) 827 828 static inline void signal_set_stop_flags(struct signal_struct *sig, 829 unsigned int flags) 830 { 831 WARN_ON(sig->flags & (SIGNAL_GROUP_EXIT|SIGNAL_GROUP_COREDUMP)); 832 sig->flags = (sig->flags & ~SIGNAL_STOP_MASK) | flags; 833 } 834 835 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 836 static inline int signal_group_exit(const struct signal_struct *sig) 837 { 838 return (sig->flags & SIGNAL_GROUP_EXIT) || 839 (sig->group_exit_task != NULL); 840 } 841 842 /* 843 * Some day this will be a full-fledged user tracking system.. 844 */ 845 struct user_struct { 846 atomic_t __count; /* reference count */ 847 atomic_t processes; /* How many processes does this user have? */ 848 atomic_t sigpending; /* How many pending signals does this user have? */ 849 #ifdef CONFIG_INOTIFY_USER 850 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 851 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 852 #endif 853 #ifdef CONFIG_FANOTIFY 854 atomic_t fanotify_listeners; 855 #endif 856 #ifdef CONFIG_EPOLL 857 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 858 #endif 859 #ifdef CONFIG_POSIX_MQUEUE 860 /* protected by mq_lock */ 861 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 862 #endif 863 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 864 unsigned long unix_inflight; /* How many files in flight in unix sockets */ 865 atomic_long_t pipe_bufs; /* how many pages are allocated in pipe buffers */ 866 867 #ifdef CONFIG_KEYS 868 struct key *uid_keyring; /* UID specific keyring */ 869 struct key *session_keyring; /* UID's default session keyring */ 870 #endif 871 872 /* Hash table maintenance information */ 873 struct hlist_node uidhash_node; 874 kuid_t uid; 875 876 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL) 877 atomic_long_t locked_vm; 878 #endif 879 }; 880 881 extern int uids_sysfs_init(void); 882 883 extern struct user_struct *find_user(kuid_t); 884 885 extern struct user_struct root_user; 886 #define INIT_USER (&root_user) 887 888 889 struct backing_dev_info; 890 struct reclaim_state; 891 892 #ifdef CONFIG_SCHED_INFO 893 struct sched_info { 894 /* cumulative counters */ 895 unsigned long pcount; /* # of times run on this cpu */ 896 unsigned long long run_delay; /* time spent waiting on a runqueue */ 897 898 /* timestamps */ 899 unsigned long long last_arrival,/* when we last ran on a cpu */ 900 last_queued; /* when we were last queued to run */ 901 }; 902 #endif /* CONFIG_SCHED_INFO */ 903 904 #ifdef CONFIG_TASK_DELAY_ACCT 905 struct task_delay_info { 906 spinlock_t lock; 907 unsigned int flags; /* Private per-task flags */ 908 909 /* For each stat XXX, add following, aligned appropriately 910 * 911 * struct timespec XXX_start, XXX_end; 912 * u64 XXX_delay; 913 * u32 XXX_count; 914 * 915 * Atomicity of updates to XXX_delay, XXX_count protected by 916 * single lock above (split into XXX_lock if contention is an issue). 917 */ 918 919 /* 920 * XXX_count is incremented on every XXX operation, the delay 921 * associated with the operation is added to XXX_delay. 922 * XXX_delay contains the accumulated delay time in nanoseconds. 923 */ 924 u64 blkio_start; /* Shared by blkio, swapin */ 925 u64 blkio_delay; /* wait for sync block io completion */ 926 u64 swapin_delay; /* wait for swapin block io completion */ 927 u32 blkio_count; /* total count of the number of sync block */ 928 /* io operations performed */ 929 u32 swapin_count; /* total count of the number of swapin block */ 930 /* io operations performed */ 931 932 u64 freepages_start; 933 u64 freepages_delay; /* wait for memory reclaim */ 934 u32 freepages_count; /* total count of memory reclaim */ 935 }; 936 #endif /* CONFIG_TASK_DELAY_ACCT */ 937 938 static inline int sched_info_on(void) 939 { 940 #ifdef CONFIG_SCHEDSTATS 941 return 1; 942 #elif defined(CONFIG_TASK_DELAY_ACCT) 943 extern int delayacct_on; 944 return delayacct_on; 945 #else 946 return 0; 947 #endif 948 } 949 950 #ifdef CONFIG_SCHEDSTATS 951 void force_schedstat_enabled(void); 952 #endif 953 954 enum cpu_idle_type { 955 CPU_IDLE, 956 CPU_NOT_IDLE, 957 CPU_NEWLY_IDLE, 958 CPU_MAX_IDLE_TYPES 959 }; 960 961 /* 962 * Integer metrics need fixed point arithmetic, e.g., sched/fair 963 * has a few: load, load_avg, util_avg, freq, and capacity. 964 * 965 * We define a basic fixed point arithmetic range, and then formalize 966 * all these metrics based on that basic range. 967 */ 968 # define SCHED_FIXEDPOINT_SHIFT 10 969 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 970 971 /* 972 * Increase resolution of cpu_capacity calculations 973 */ 974 #define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 975 #define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 976 977 /* 978 * Wake-queues are lists of tasks with a pending wakeup, whose 979 * callers have already marked the task as woken internally, 980 * and can thus carry on. A common use case is being able to 981 * do the wakeups once the corresponding user lock as been 982 * released. 983 * 984 * We hold reference to each task in the list across the wakeup, 985 * thus guaranteeing that the memory is still valid by the time 986 * the actual wakeups are performed in wake_up_q(). 987 * 988 * One per task suffices, because there's never a need for a task to be 989 * in two wake queues simultaneously; it is forbidden to abandon a task 990 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is 991 * already in a wake queue, the wakeup will happen soon and the second 992 * waker can just skip it. 993 * 994 * The DEFINE_WAKE_Q macro declares and initializes the list head. 995 * wake_up_q() does NOT reinitialize the list; it's expected to be 996 * called near the end of a function. Otherwise, the list can be 997 * re-initialized for later re-use by wake_q_init(). 998 * 999 * Note that this can cause spurious wakeups. schedule() callers 1000 * must ensure the call is done inside a loop, confirming that the 1001 * wakeup condition has in fact occurred. 1002 */ 1003 struct wake_q_node { 1004 struct wake_q_node *next; 1005 }; 1006 1007 struct wake_q_head { 1008 struct wake_q_node *first; 1009 struct wake_q_node **lastp; 1010 }; 1011 1012 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01) 1013 1014 #define DEFINE_WAKE_Q(name) \ 1015 struct wake_q_head name = { WAKE_Q_TAIL, &name.first } 1016 1017 static inline void wake_q_init(struct wake_q_head *head) 1018 { 1019 head->first = WAKE_Q_TAIL; 1020 head->lastp = &head->first; 1021 } 1022 1023 extern void wake_q_add(struct wake_q_head *head, 1024 struct task_struct *task); 1025 extern void wake_up_q(struct wake_q_head *head); 1026 1027 /* 1028 * sched-domains (multiprocessor balancing) declarations: 1029 */ 1030 #ifdef CONFIG_SMP 1031 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 1032 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 1033 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 1034 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 1035 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 1036 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 1037 #define SD_ASYM_CPUCAPACITY 0x0040 /* Groups have different max cpu capacities */ 1038 #define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu capacity */ 1039 #define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ 1040 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 1041 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 1042 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 1043 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 1044 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 1045 #define SD_NUMA 0x4000 /* cross-node balancing */ 1046 1047 #ifdef CONFIG_SCHED_SMT 1048 static inline int cpu_smt_flags(void) 1049 { 1050 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; 1051 } 1052 #endif 1053 1054 #ifdef CONFIG_SCHED_MC 1055 static inline int cpu_core_flags(void) 1056 { 1057 return SD_SHARE_PKG_RESOURCES; 1058 } 1059 #endif 1060 1061 #ifdef CONFIG_NUMA 1062 static inline int cpu_numa_flags(void) 1063 { 1064 return SD_NUMA; 1065 } 1066 #endif 1067 1068 extern int arch_asym_cpu_priority(int cpu); 1069 1070 struct sched_domain_attr { 1071 int relax_domain_level; 1072 }; 1073 1074 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 1075 .relax_domain_level = -1, \ 1076 } 1077 1078 extern int sched_domain_level_max; 1079 1080 struct sched_group; 1081 1082 struct sched_domain_shared { 1083 atomic_t ref; 1084 atomic_t nr_busy_cpus; 1085 int has_idle_cores; 1086 }; 1087 1088 struct sched_domain { 1089 /* These fields must be setup */ 1090 struct sched_domain *parent; /* top domain must be null terminated */ 1091 struct sched_domain *child; /* bottom domain must be null terminated */ 1092 struct sched_group *groups; /* the balancing groups of the domain */ 1093 unsigned long min_interval; /* Minimum balance interval ms */ 1094 unsigned long max_interval; /* Maximum balance interval ms */ 1095 unsigned int busy_factor; /* less balancing by factor if busy */ 1096 unsigned int imbalance_pct; /* No balance until over watermark */ 1097 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 1098 unsigned int busy_idx; 1099 unsigned int idle_idx; 1100 unsigned int newidle_idx; 1101 unsigned int wake_idx; 1102 unsigned int forkexec_idx; 1103 unsigned int smt_gain; 1104 1105 int nohz_idle; /* NOHZ IDLE status */ 1106 int flags; /* See SD_* */ 1107 int level; 1108 1109 /* Runtime fields. */ 1110 unsigned long last_balance; /* init to jiffies. units in jiffies */ 1111 unsigned int balance_interval; /* initialise to 1. units in ms. */ 1112 unsigned int nr_balance_failed; /* initialise to 0 */ 1113 1114 /* idle_balance() stats */ 1115 u64 max_newidle_lb_cost; 1116 unsigned long next_decay_max_lb_cost; 1117 1118 u64 avg_scan_cost; /* select_idle_sibling */ 1119 1120 #ifdef CONFIG_SCHEDSTATS 1121 /* load_balance() stats */ 1122 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 1123 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 1124 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 1125 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 1126 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 1127 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 1128 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 1129 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 1130 1131 /* Active load balancing */ 1132 unsigned int alb_count; 1133 unsigned int alb_failed; 1134 unsigned int alb_pushed; 1135 1136 /* SD_BALANCE_EXEC stats */ 1137 unsigned int sbe_count; 1138 unsigned int sbe_balanced; 1139 unsigned int sbe_pushed; 1140 1141 /* SD_BALANCE_FORK stats */ 1142 unsigned int sbf_count; 1143 unsigned int sbf_balanced; 1144 unsigned int sbf_pushed; 1145 1146 /* try_to_wake_up() stats */ 1147 unsigned int ttwu_wake_remote; 1148 unsigned int ttwu_move_affine; 1149 unsigned int ttwu_move_balance; 1150 #endif 1151 #ifdef CONFIG_SCHED_DEBUG 1152 char *name; 1153 #endif 1154 union { 1155 void *private; /* used during construction */ 1156 struct rcu_head rcu; /* used during destruction */ 1157 }; 1158 struct sched_domain_shared *shared; 1159 1160 unsigned int span_weight; 1161 /* 1162 * Span of all CPUs in this domain. 1163 * 1164 * NOTE: this field is variable length. (Allocated dynamically 1165 * by attaching extra space to the end of the structure, 1166 * depending on how many CPUs the kernel has booted up with) 1167 */ 1168 unsigned long span[0]; 1169 }; 1170 1171 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 1172 { 1173 return to_cpumask(sd->span); 1174 } 1175 1176 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1177 struct sched_domain_attr *dattr_new); 1178 1179 /* Allocate an array of sched domains, for partition_sched_domains(). */ 1180 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 1181 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 1182 1183 bool cpus_share_cache(int this_cpu, int that_cpu); 1184 1185 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); 1186 typedef int (*sched_domain_flags_f)(void); 1187 1188 #define SDTL_OVERLAP 0x01 1189 1190 struct sd_data { 1191 struct sched_domain **__percpu sd; 1192 struct sched_domain_shared **__percpu sds; 1193 struct sched_group **__percpu sg; 1194 struct sched_group_capacity **__percpu sgc; 1195 }; 1196 1197 struct sched_domain_topology_level { 1198 sched_domain_mask_f mask; 1199 sched_domain_flags_f sd_flags; 1200 int flags; 1201 int numa_level; 1202 struct sd_data data; 1203 #ifdef CONFIG_SCHED_DEBUG 1204 char *name; 1205 #endif 1206 }; 1207 1208 extern void set_sched_topology(struct sched_domain_topology_level *tl); 1209 extern void wake_up_if_idle(int cpu); 1210 1211 #ifdef CONFIG_SCHED_DEBUG 1212 # define SD_INIT_NAME(type) .name = #type 1213 #else 1214 # define SD_INIT_NAME(type) 1215 #endif 1216 1217 #else /* CONFIG_SMP */ 1218 1219 struct sched_domain_attr; 1220 1221 static inline void 1222 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1223 struct sched_domain_attr *dattr_new) 1224 { 1225 } 1226 1227 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1228 { 1229 return true; 1230 } 1231 1232 #endif /* !CONFIG_SMP */ 1233 1234 1235 struct io_context; /* See blkdev.h */ 1236 1237 1238 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1239 extern void prefetch_stack(struct task_struct *t); 1240 #else 1241 static inline void prefetch_stack(struct task_struct *t) { } 1242 #endif 1243 1244 struct audit_context; /* See audit.c */ 1245 struct mempolicy; 1246 struct pipe_inode_info; 1247 struct uts_namespace; 1248 1249 struct load_weight { 1250 unsigned long weight; 1251 u32 inv_weight; 1252 }; 1253 1254 /* 1255 * The load_avg/util_avg accumulates an infinite geometric series 1256 * (see __update_load_avg() in kernel/sched/fair.c). 1257 * 1258 * [load_avg definition] 1259 * 1260 * load_avg = runnable% * scale_load_down(load) 1261 * 1262 * where runnable% is the time ratio that a sched_entity is runnable. 1263 * For cfs_rq, it is the aggregated load_avg of all runnable and 1264 * blocked sched_entities. 1265 * 1266 * load_avg may also take frequency scaling into account: 1267 * 1268 * load_avg = runnable% * scale_load_down(load) * freq% 1269 * 1270 * where freq% is the CPU frequency normalized to the highest frequency. 1271 * 1272 * [util_avg definition] 1273 * 1274 * util_avg = running% * SCHED_CAPACITY_SCALE 1275 * 1276 * where running% is the time ratio that a sched_entity is running on 1277 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable 1278 * and blocked sched_entities. 1279 * 1280 * util_avg may also factor frequency scaling and CPU capacity scaling: 1281 * 1282 * util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity% 1283 * 1284 * where freq% is the same as above, and capacity% is the CPU capacity 1285 * normalized to the greatest capacity (due to uarch differences, etc). 1286 * 1287 * N.B., the above ratios (runnable%, running%, freq%, and capacity%) 1288 * themselves are in the range of [0, 1]. To do fixed point arithmetics, 1289 * we therefore scale them to as large a range as necessary. This is for 1290 * example reflected by util_avg's SCHED_CAPACITY_SCALE. 1291 * 1292 * [Overflow issue] 1293 * 1294 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 1295 * with the highest load (=88761), always runnable on a single cfs_rq, 1296 * and should not overflow as the number already hits PID_MAX_LIMIT. 1297 * 1298 * For all other cases (including 32-bit kernels), struct load_weight's 1299 * weight will overflow first before we do, because: 1300 * 1301 * Max(load_avg) <= Max(load.weight) 1302 * 1303 * Then it is the load_weight's responsibility to consider overflow 1304 * issues. 1305 */ 1306 struct sched_avg { 1307 u64 last_update_time, load_sum; 1308 u32 util_sum, period_contrib; 1309 unsigned long load_avg, util_avg; 1310 }; 1311 1312 #ifdef CONFIG_SCHEDSTATS 1313 struct sched_statistics { 1314 u64 wait_start; 1315 u64 wait_max; 1316 u64 wait_count; 1317 u64 wait_sum; 1318 u64 iowait_count; 1319 u64 iowait_sum; 1320 1321 u64 sleep_start; 1322 u64 sleep_max; 1323 s64 sum_sleep_runtime; 1324 1325 u64 block_start; 1326 u64 block_max; 1327 u64 exec_max; 1328 u64 slice_max; 1329 1330 u64 nr_migrations_cold; 1331 u64 nr_failed_migrations_affine; 1332 u64 nr_failed_migrations_running; 1333 u64 nr_failed_migrations_hot; 1334 u64 nr_forced_migrations; 1335 1336 u64 nr_wakeups; 1337 u64 nr_wakeups_sync; 1338 u64 nr_wakeups_migrate; 1339 u64 nr_wakeups_local; 1340 u64 nr_wakeups_remote; 1341 u64 nr_wakeups_affine; 1342 u64 nr_wakeups_affine_attempts; 1343 u64 nr_wakeups_passive; 1344 u64 nr_wakeups_idle; 1345 }; 1346 #endif 1347 1348 struct sched_entity { 1349 struct load_weight load; /* for load-balancing */ 1350 struct rb_node run_node; 1351 struct list_head group_node; 1352 unsigned int on_rq; 1353 1354 u64 exec_start; 1355 u64 sum_exec_runtime; 1356 u64 vruntime; 1357 u64 prev_sum_exec_runtime; 1358 1359 u64 nr_migrations; 1360 1361 #ifdef CONFIG_SCHEDSTATS 1362 struct sched_statistics statistics; 1363 #endif 1364 1365 #ifdef CONFIG_FAIR_GROUP_SCHED 1366 int depth; 1367 struct sched_entity *parent; 1368 /* rq on which this entity is (to be) queued: */ 1369 struct cfs_rq *cfs_rq; 1370 /* rq "owned" by this entity/group: */ 1371 struct cfs_rq *my_q; 1372 #endif 1373 1374 #ifdef CONFIG_SMP 1375 /* 1376 * Per entity load average tracking. 1377 * 1378 * Put into separate cache line so it does not 1379 * collide with read-mostly values above. 1380 */ 1381 struct sched_avg avg ____cacheline_aligned_in_smp; 1382 #endif 1383 }; 1384 1385 struct sched_rt_entity { 1386 struct list_head run_list; 1387 unsigned long timeout; 1388 unsigned long watchdog_stamp; 1389 unsigned int time_slice; 1390 unsigned short on_rq; 1391 unsigned short on_list; 1392 1393 struct sched_rt_entity *back; 1394 #ifdef CONFIG_RT_GROUP_SCHED 1395 struct sched_rt_entity *parent; 1396 /* rq on which this entity is (to be) queued: */ 1397 struct rt_rq *rt_rq; 1398 /* rq "owned" by this entity/group: */ 1399 struct rt_rq *my_q; 1400 #endif 1401 }; 1402 1403 struct sched_dl_entity { 1404 struct rb_node rb_node; 1405 1406 /* 1407 * Original scheduling parameters. Copied here from sched_attr 1408 * during sched_setattr(), they will remain the same until 1409 * the next sched_setattr(). 1410 */ 1411 u64 dl_runtime; /* maximum runtime for each instance */ 1412 u64 dl_deadline; /* relative deadline of each instance */ 1413 u64 dl_period; /* separation of two instances (period) */ 1414 u64 dl_bw; /* dl_runtime / dl_deadline */ 1415 1416 /* 1417 * Actual scheduling parameters. Initialized with the values above, 1418 * they are continously updated during task execution. Note that 1419 * the remaining runtime could be < 0 in case we are in overrun. 1420 */ 1421 s64 runtime; /* remaining runtime for this instance */ 1422 u64 deadline; /* absolute deadline for this instance */ 1423 unsigned int flags; /* specifying the scheduler behaviour */ 1424 1425 /* 1426 * Some bool flags: 1427 * 1428 * @dl_throttled tells if we exhausted the runtime. If so, the 1429 * task has to wait for a replenishment to be performed at the 1430 * next firing of dl_timer. 1431 * 1432 * @dl_boosted tells if we are boosted due to DI. If so we are 1433 * outside bandwidth enforcement mechanism (but only until we 1434 * exit the critical section); 1435 * 1436 * @dl_yielded tells if task gave up the cpu before consuming 1437 * all its available runtime during the last job. 1438 */ 1439 int dl_throttled, dl_boosted, dl_yielded; 1440 1441 /* 1442 * Bandwidth enforcement timer. Each -deadline task has its 1443 * own bandwidth to be enforced, thus we need one timer per task. 1444 */ 1445 struct hrtimer dl_timer; 1446 }; 1447 1448 union rcu_special { 1449 struct { 1450 u8 blocked; 1451 u8 need_qs; 1452 u8 exp_need_qs; 1453 u8 pad; /* Otherwise the compiler can store garbage here. */ 1454 } b; /* Bits. */ 1455 u32 s; /* Set of bits. */ 1456 }; 1457 struct rcu_node; 1458 1459 enum perf_event_task_context { 1460 perf_invalid_context = -1, 1461 perf_hw_context = 0, 1462 perf_sw_context, 1463 perf_nr_task_contexts, 1464 }; 1465 1466 /* Track pages that require TLB flushes */ 1467 struct tlbflush_unmap_batch { 1468 /* 1469 * Each bit set is a CPU that potentially has a TLB entry for one of 1470 * the PFNs being flushed. See set_tlb_ubc_flush_pending(). 1471 */ 1472 struct cpumask cpumask; 1473 1474 /* True if any bit in cpumask is set */ 1475 bool flush_required; 1476 1477 /* 1478 * If true then the PTE was dirty when unmapped. The entry must be 1479 * flushed before IO is initiated or a stale TLB entry potentially 1480 * allows an update without redirtying the page. 1481 */ 1482 bool writable; 1483 }; 1484 1485 struct task_struct { 1486 #ifdef CONFIG_THREAD_INFO_IN_TASK 1487 /* 1488 * For reasons of header soup (see current_thread_info()), this 1489 * must be the first element of task_struct. 1490 */ 1491 struct thread_info thread_info; 1492 #endif 1493 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1494 void *stack; 1495 atomic_t usage; 1496 unsigned int flags; /* per process flags, defined below */ 1497 unsigned int ptrace; 1498 1499 #ifdef CONFIG_SMP 1500 struct llist_node wake_entry; 1501 int on_cpu; 1502 #ifdef CONFIG_THREAD_INFO_IN_TASK 1503 unsigned int cpu; /* current CPU */ 1504 #endif 1505 unsigned int wakee_flips; 1506 unsigned long wakee_flip_decay_ts; 1507 struct task_struct *last_wakee; 1508 1509 int wake_cpu; 1510 #endif 1511 int on_rq; 1512 1513 int prio, static_prio, normal_prio; 1514 unsigned int rt_priority; 1515 const struct sched_class *sched_class; 1516 struct sched_entity se; 1517 struct sched_rt_entity rt; 1518 #ifdef CONFIG_CGROUP_SCHED 1519 struct task_group *sched_task_group; 1520 #endif 1521 struct sched_dl_entity dl; 1522 1523 #ifdef CONFIG_PREEMPT_NOTIFIERS 1524 /* list of struct preempt_notifier: */ 1525 struct hlist_head preempt_notifiers; 1526 #endif 1527 1528 #ifdef CONFIG_BLK_DEV_IO_TRACE 1529 unsigned int btrace_seq; 1530 #endif 1531 1532 unsigned int policy; 1533 int nr_cpus_allowed; 1534 cpumask_t cpus_allowed; 1535 1536 #ifdef CONFIG_PREEMPT_RCU 1537 int rcu_read_lock_nesting; 1538 union rcu_special rcu_read_unlock_special; 1539 struct list_head rcu_node_entry; 1540 struct rcu_node *rcu_blocked_node; 1541 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1542 #ifdef CONFIG_TASKS_RCU 1543 unsigned long rcu_tasks_nvcsw; 1544 bool rcu_tasks_holdout; 1545 struct list_head rcu_tasks_holdout_list; 1546 int rcu_tasks_idle_cpu; 1547 #endif /* #ifdef CONFIG_TASKS_RCU */ 1548 1549 #ifdef CONFIG_SCHED_INFO 1550 struct sched_info sched_info; 1551 #endif 1552 1553 struct list_head tasks; 1554 #ifdef CONFIG_SMP 1555 struct plist_node pushable_tasks; 1556 struct rb_node pushable_dl_tasks; 1557 #endif 1558 1559 struct mm_struct *mm, *active_mm; 1560 /* per-thread vma caching */ 1561 u32 vmacache_seqnum; 1562 struct vm_area_struct *vmacache[VMACACHE_SIZE]; 1563 #if defined(SPLIT_RSS_COUNTING) 1564 struct task_rss_stat rss_stat; 1565 #endif 1566 /* task state */ 1567 int exit_state; 1568 int exit_code, exit_signal; 1569 int pdeath_signal; /* The signal sent when the parent dies */ 1570 unsigned long jobctl; /* JOBCTL_*, siglock protected */ 1571 1572 /* Used for emulating ABI behavior of previous Linux versions */ 1573 unsigned int personality; 1574 1575 /* scheduler bits, serialized by scheduler locks */ 1576 unsigned sched_reset_on_fork:1; 1577 unsigned sched_contributes_to_load:1; 1578 unsigned sched_migrated:1; 1579 unsigned sched_remote_wakeup:1; 1580 unsigned :0; /* force alignment to the next boundary */ 1581 1582 /* unserialized, strictly 'current' */ 1583 unsigned in_execve:1; /* bit to tell LSMs we're in execve */ 1584 unsigned in_iowait:1; 1585 #if !defined(TIF_RESTORE_SIGMASK) 1586 unsigned restore_sigmask:1; 1587 #endif 1588 #ifdef CONFIG_MEMCG 1589 unsigned memcg_may_oom:1; 1590 #ifndef CONFIG_SLOB 1591 unsigned memcg_kmem_skip_account:1; 1592 #endif 1593 #endif 1594 #ifdef CONFIG_COMPAT_BRK 1595 unsigned brk_randomized:1; 1596 #endif 1597 1598 unsigned long atomic_flags; /* Flags needing atomic access. */ 1599 1600 struct restart_block restart_block; 1601 1602 pid_t pid; 1603 pid_t tgid; 1604 1605 #ifdef CONFIG_CC_STACKPROTECTOR 1606 /* Canary value for the -fstack-protector gcc feature */ 1607 unsigned long stack_canary; 1608 #endif 1609 /* 1610 * pointers to (original) parent process, youngest child, younger sibling, 1611 * older sibling, respectively. (p->father can be replaced with 1612 * p->real_parent->pid) 1613 */ 1614 struct task_struct __rcu *real_parent; /* real parent process */ 1615 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1616 /* 1617 * children/sibling forms the list of my natural children 1618 */ 1619 struct list_head children; /* list of my children */ 1620 struct list_head sibling; /* linkage in my parent's children list */ 1621 struct task_struct *group_leader; /* threadgroup leader */ 1622 1623 /* 1624 * ptraced is the list of tasks this task is using ptrace on. 1625 * This includes both natural children and PTRACE_ATTACH targets. 1626 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1627 */ 1628 struct list_head ptraced; 1629 struct list_head ptrace_entry; 1630 1631 /* PID/PID hash table linkage. */ 1632 struct pid_link pids[PIDTYPE_MAX]; 1633 struct list_head thread_group; 1634 struct list_head thread_node; 1635 1636 struct completion *vfork_done; /* for vfork() */ 1637 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1638 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1639 1640 u64 utime, stime; 1641 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 1642 u64 utimescaled, stimescaled; 1643 #endif 1644 u64 gtime; 1645 struct prev_cputime prev_cputime; 1646 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1647 seqcount_t vtime_seqcount; 1648 unsigned long long vtime_snap; 1649 enum { 1650 /* Task is sleeping or running in a CPU with VTIME inactive */ 1651 VTIME_INACTIVE = 0, 1652 /* Task runs in userspace in a CPU with VTIME active */ 1653 VTIME_USER, 1654 /* Task runs in kernelspace in a CPU with VTIME active */ 1655 VTIME_SYS, 1656 } vtime_snap_whence; 1657 #endif 1658 1659 #ifdef CONFIG_NO_HZ_FULL 1660 atomic_t tick_dep_mask; 1661 #endif 1662 unsigned long nvcsw, nivcsw; /* context switch counts */ 1663 u64 start_time; /* monotonic time in nsec */ 1664 u64 real_start_time; /* boot based time in nsec */ 1665 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1666 unsigned long min_flt, maj_flt; 1667 1668 #ifdef CONFIG_POSIX_TIMERS 1669 struct task_cputime cputime_expires; 1670 struct list_head cpu_timers[3]; 1671 #endif 1672 1673 /* process credentials */ 1674 const struct cred __rcu *ptracer_cred; /* Tracer's credentials at attach */ 1675 const struct cred __rcu *real_cred; /* objective and real subjective task 1676 * credentials (COW) */ 1677 const struct cred __rcu *cred; /* effective (overridable) subjective task 1678 * credentials (COW) */ 1679 char comm[TASK_COMM_LEN]; /* executable name excluding path 1680 - access with [gs]et_task_comm (which lock 1681 it with task_lock()) 1682 - initialized normally by setup_new_exec */ 1683 /* file system info */ 1684 struct nameidata *nameidata; 1685 #ifdef CONFIG_SYSVIPC 1686 /* ipc stuff */ 1687 struct sysv_sem sysvsem; 1688 struct sysv_shm sysvshm; 1689 #endif 1690 #ifdef CONFIG_DETECT_HUNG_TASK 1691 /* hung task detection */ 1692 unsigned long last_switch_count; 1693 #endif 1694 /* filesystem information */ 1695 struct fs_struct *fs; 1696 /* open file information */ 1697 struct files_struct *files; 1698 /* namespaces */ 1699 struct nsproxy *nsproxy; 1700 /* signal handlers */ 1701 struct signal_struct *signal; 1702 struct sighand_struct *sighand; 1703 1704 sigset_t blocked, real_blocked; 1705 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1706 struct sigpending pending; 1707 1708 unsigned long sas_ss_sp; 1709 size_t sas_ss_size; 1710 unsigned sas_ss_flags; 1711 1712 struct callback_head *task_works; 1713 1714 struct audit_context *audit_context; 1715 #ifdef CONFIG_AUDITSYSCALL 1716 kuid_t loginuid; 1717 unsigned int sessionid; 1718 #endif 1719 struct seccomp seccomp; 1720 1721 /* Thread group tracking */ 1722 u32 parent_exec_id; 1723 u32 self_exec_id; 1724 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1725 * mempolicy */ 1726 spinlock_t alloc_lock; 1727 1728 /* Protection of the PI data structures: */ 1729 raw_spinlock_t pi_lock; 1730 1731 struct wake_q_node wake_q; 1732 1733 #ifdef CONFIG_RT_MUTEXES 1734 /* PI waiters blocked on a rt_mutex held by this task */ 1735 struct rb_root pi_waiters; 1736 struct rb_node *pi_waiters_leftmost; 1737 /* Deadlock detection and priority inheritance handling */ 1738 struct rt_mutex_waiter *pi_blocked_on; 1739 #endif 1740 1741 #ifdef CONFIG_DEBUG_MUTEXES 1742 /* mutex deadlock detection */ 1743 struct mutex_waiter *blocked_on; 1744 #endif 1745 #ifdef CONFIG_TRACE_IRQFLAGS 1746 unsigned int irq_events; 1747 unsigned long hardirq_enable_ip; 1748 unsigned long hardirq_disable_ip; 1749 unsigned int hardirq_enable_event; 1750 unsigned int hardirq_disable_event; 1751 int hardirqs_enabled; 1752 int hardirq_context; 1753 unsigned long softirq_disable_ip; 1754 unsigned long softirq_enable_ip; 1755 unsigned int softirq_disable_event; 1756 unsigned int softirq_enable_event; 1757 int softirqs_enabled; 1758 int softirq_context; 1759 #endif 1760 #ifdef CONFIG_LOCKDEP 1761 # define MAX_LOCK_DEPTH 48UL 1762 u64 curr_chain_key; 1763 int lockdep_depth; 1764 unsigned int lockdep_recursion; 1765 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1766 gfp_t lockdep_reclaim_gfp; 1767 #endif 1768 #ifdef CONFIG_UBSAN 1769 unsigned int in_ubsan; 1770 #endif 1771 1772 /* journalling filesystem info */ 1773 void *journal_info; 1774 1775 /* stacked block device info */ 1776 struct bio_list *bio_list; 1777 1778 #ifdef CONFIG_BLOCK 1779 /* stack plugging */ 1780 struct blk_plug *plug; 1781 #endif 1782 1783 /* VM state */ 1784 struct reclaim_state *reclaim_state; 1785 1786 struct backing_dev_info *backing_dev_info; 1787 1788 struct io_context *io_context; 1789 1790 unsigned long ptrace_message; 1791 siginfo_t *last_siginfo; /* For ptrace use. */ 1792 struct task_io_accounting ioac; 1793 #if defined(CONFIG_TASK_XACCT) 1794 u64 acct_rss_mem1; /* accumulated rss usage */ 1795 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1796 u64 acct_timexpd; /* stime + utime since last update */ 1797 #endif 1798 #ifdef CONFIG_CPUSETS 1799 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1800 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1801 int cpuset_mem_spread_rotor; 1802 int cpuset_slab_spread_rotor; 1803 #endif 1804 #ifdef CONFIG_CGROUPS 1805 /* Control Group info protected by css_set_lock */ 1806 struct css_set __rcu *cgroups; 1807 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1808 struct list_head cg_list; 1809 #endif 1810 #ifdef CONFIG_INTEL_RDT_A 1811 int closid; 1812 #endif 1813 #ifdef CONFIG_FUTEX 1814 struct robust_list_head __user *robust_list; 1815 #ifdef CONFIG_COMPAT 1816 struct compat_robust_list_head __user *compat_robust_list; 1817 #endif 1818 struct list_head pi_state_list; 1819 struct futex_pi_state *pi_state_cache; 1820 #endif 1821 #ifdef CONFIG_PERF_EVENTS 1822 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1823 struct mutex perf_event_mutex; 1824 struct list_head perf_event_list; 1825 #endif 1826 #ifdef CONFIG_DEBUG_PREEMPT 1827 unsigned long preempt_disable_ip; 1828 #endif 1829 #ifdef CONFIG_NUMA 1830 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1831 short il_next; 1832 short pref_node_fork; 1833 #endif 1834 #ifdef CONFIG_NUMA_BALANCING 1835 int numa_scan_seq; 1836 unsigned int numa_scan_period; 1837 unsigned int numa_scan_period_max; 1838 int numa_preferred_nid; 1839 unsigned long numa_migrate_retry; 1840 u64 node_stamp; /* migration stamp */ 1841 u64 last_task_numa_placement; 1842 u64 last_sum_exec_runtime; 1843 struct callback_head numa_work; 1844 1845 struct list_head numa_entry; 1846 struct numa_group *numa_group; 1847 1848 /* 1849 * numa_faults is an array split into four regions: 1850 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1851 * in this precise order. 1852 * 1853 * faults_memory: Exponential decaying average of faults on a per-node 1854 * basis. Scheduling placement decisions are made based on these 1855 * counts. The values remain static for the duration of a PTE scan. 1856 * faults_cpu: Track the nodes the process was running on when a NUMA 1857 * hinting fault was incurred. 1858 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1859 * during the current scan window. When the scan completes, the counts 1860 * in faults_memory and faults_cpu decay and these values are copied. 1861 */ 1862 unsigned long *numa_faults; 1863 unsigned long total_numa_faults; 1864 1865 /* 1866 * numa_faults_locality tracks if faults recorded during the last 1867 * scan window were remote/local or failed to migrate. The task scan 1868 * period is adapted based on the locality of the faults with different 1869 * weights depending on whether they were shared or private faults 1870 */ 1871 unsigned long numa_faults_locality[3]; 1872 1873 unsigned long numa_pages_migrated; 1874 #endif /* CONFIG_NUMA_BALANCING */ 1875 1876 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 1877 struct tlbflush_unmap_batch tlb_ubc; 1878 #endif 1879 1880 struct rcu_head rcu; 1881 1882 /* 1883 * cache last used pipe for splice 1884 */ 1885 struct pipe_inode_info *splice_pipe; 1886 1887 struct page_frag task_frag; 1888 1889 #ifdef CONFIG_TASK_DELAY_ACCT 1890 struct task_delay_info *delays; 1891 #endif 1892 #ifdef CONFIG_FAULT_INJECTION 1893 int make_it_fail; 1894 #endif 1895 /* 1896 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1897 * balance_dirty_pages() for some dirty throttling pause 1898 */ 1899 int nr_dirtied; 1900 int nr_dirtied_pause; 1901 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1902 1903 #ifdef CONFIG_LATENCYTOP 1904 int latency_record_count; 1905 struct latency_record latency_record[LT_SAVECOUNT]; 1906 #endif 1907 /* 1908 * time slack values; these are used to round up poll() and 1909 * select() etc timeout values. These are in nanoseconds. 1910 */ 1911 u64 timer_slack_ns; 1912 u64 default_timer_slack_ns; 1913 1914 #ifdef CONFIG_KASAN 1915 unsigned int kasan_depth; 1916 #endif 1917 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1918 /* Index of current stored address in ret_stack */ 1919 int curr_ret_stack; 1920 /* Stack of return addresses for return function tracing */ 1921 struct ftrace_ret_stack *ret_stack; 1922 /* time stamp for last schedule */ 1923 unsigned long long ftrace_timestamp; 1924 /* 1925 * Number of functions that haven't been traced 1926 * because of depth overrun. 1927 */ 1928 atomic_t trace_overrun; 1929 /* Pause for the tracing */ 1930 atomic_t tracing_graph_pause; 1931 #endif 1932 #ifdef CONFIG_TRACING 1933 /* state flags for use by tracers */ 1934 unsigned long trace; 1935 /* bitmask and counter of trace recursion */ 1936 unsigned long trace_recursion; 1937 #endif /* CONFIG_TRACING */ 1938 #ifdef CONFIG_KCOV 1939 /* Coverage collection mode enabled for this task (0 if disabled). */ 1940 enum kcov_mode kcov_mode; 1941 /* Size of the kcov_area. */ 1942 unsigned kcov_size; 1943 /* Buffer for coverage collection. */ 1944 void *kcov_area; 1945 /* kcov desciptor wired with this task or NULL. */ 1946 struct kcov *kcov; 1947 #endif 1948 #ifdef CONFIG_MEMCG 1949 struct mem_cgroup *memcg_in_oom; 1950 gfp_t memcg_oom_gfp_mask; 1951 int memcg_oom_order; 1952 1953 /* number of pages to reclaim on returning to userland */ 1954 unsigned int memcg_nr_pages_over_high; 1955 #endif 1956 #ifdef CONFIG_UPROBES 1957 struct uprobe_task *utask; 1958 #endif 1959 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1960 unsigned int sequential_io; 1961 unsigned int sequential_io_avg; 1962 #endif 1963 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1964 unsigned long task_state_change; 1965 #endif 1966 int pagefault_disabled; 1967 #ifdef CONFIG_MMU 1968 struct task_struct *oom_reaper_list; 1969 #endif 1970 #ifdef CONFIG_VMAP_STACK 1971 struct vm_struct *stack_vm_area; 1972 #endif 1973 #ifdef CONFIG_THREAD_INFO_IN_TASK 1974 /* A live task holds one reference. */ 1975 atomic_t stack_refcount; 1976 #endif 1977 /* CPU-specific state of this task */ 1978 struct thread_struct thread; 1979 /* 1980 * WARNING: on x86, 'thread_struct' contains a variable-sized 1981 * structure. It *MUST* be at the end of 'task_struct'. 1982 * 1983 * Do not put anything below here! 1984 */ 1985 }; 1986 1987 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT 1988 extern int arch_task_struct_size __read_mostly; 1989 #else 1990 # define arch_task_struct_size (sizeof(struct task_struct)) 1991 #endif 1992 1993 #ifdef CONFIG_VMAP_STACK 1994 static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t) 1995 { 1996 return t->stack_vm_area; 1997 } 1998 #else 1999 static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t) 2000 { 2001 return NULL; 2002 } 2003 #endif 2004 2005 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 2006 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 2007 2008 static inline int tsk_nr_cpus_allowed(struct task_struct *p) 2009 { 2010 return p->nr_cpus_allowed; 2011 } 2012 2013 #define TNF_MIGRATED 0x01 2014 #define TNF_NO_GROUP 0x02 2015 #define TNF_SHARED 0x04 2016 #define TNF_FAULT_LOCAL 0x08 2017 #define TNF_MIGRATE_FAIL 0x10 2018 2019 static inline bool in_vfork(struct task_struct *tsk) 2020 { 2021 bool ret; 2022 2023 /* 2024 * need RCU to access ->real_parent if CLONE_VM was used along with 2025 * CLONE_PARENT. 2026 * 2027 * We check real_parent->mm == tsk->mm because CLONE_VFORK does not 2028 * imply CLONE_VM 2029 * 2030 * CLONE_VFORK can be used with CLONE_PARENT/CLONE_THREAD and thus 2031 * ->real_parent is not necessarily the task doing vfork(), so in 2032 * theory we can't rely on task_lock() if we want to dereference it. 2033 * 2034 * And in this case we can't trust the real_parent->mm == tsk->mm 2035 * check, it can be false negative. But we do not care, if init or 2036 * another oom-unkillable task does this it should blame itself. 2037 */ 2038 rcu_read_lock(); 2039 ret = tsk->vfork_done && tsk->real_parent->mm == tsk->mm; 2040 rcu_read_unlock(); 2041 2042 return ret; 2043 } 2044 2045 #ifdef CONFIG_NUMA_BALANCING 2046 extern void task_numa_fault(int last_node, int node, int pages, int flags); 2047 extern pid_t task_numa_group_id(struct task_struct *p); 2048 extern void set_numabalancing_state(bool enabled); 2049 extern void task_numa_free(struct task_struct *p); 2050 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page, 2051 int src_nid, int dst_cpu); 2052 #else 2053 static inline void task_numa_fault(int last_node, int node, int pages, 2054 int flags) 2055 { 2056 } 2057 static inline pid_t task_numa_group_id(struct task_struct *p) 2058 { 2059 return 0; 2060 } 2061 static inline void set_numabalancing_state(bool enabled) 2062 { 2063 } 2064 static inline void task_numa_free(struct task_struct *p) 2065 { 2066 } 2067 static inline bool should_numa_migrate_memory(struct task_struct *p, 2068 struct page *page, int src_nid, int dst_cpu) 2069 { 2070 return true; 2071 } 2072 #endif 2073 2074 static inline struct pid *task_pid(struct task_struct *task) 2075 { 2076 return task->pids[PIDTYPE_PID].pid; 2077 } 2078 2079 static inline struct pid *task_tgid(struct task_struct *task) 2080 { 2081 return task->group_leader->pids[PIDTYPE_PID].pid; 2082 } 2083 2084 /* 2085 * Without tasklist or rcu lock it is not safe to dereference 2086 * the result of task_pgrp/task_session even if task == current, 2087 * we can race with another thread doing sys_setsid/sys_setpgid. 2088 */ 2089 static inline struct pid *task_pgrp(struct task_struct *task) 2090 { 2091 return task->group_leader->pids[PIDTYPE_PGID].pid; 2092 } 2093 2094 static inline struct pid *task_session(struct task_struct *task) 2095 { 2096 return task->group_leader->pids[PIDTYPE_SID].pid; 2097 } 2098 2099 struct pid_namespace; 2100 2101 /* 2102 * the helpers to get the task's different pids as they are seen 2103 * from various namespaces 2104 * 2105 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 2106 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 2107 * current. 2108 * task_xid_nr_ns() : id seen from the ns specified; 2109 * 2110 * set_task_vxid() : assigns a virtual id to a task; 2111 * 2112 * see also pid_nr() etc in include/linux/pid.h 2113 */ 2114 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 2115 struct pid_namespace *ns); 2116 2117 static inline pid_t task_pid_nr(struct task_struct *tsk) 2118 { 2119 return tsk->pid; 2120 } 2121 2122 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 2123 struct pid_namespace *ns) 2124 { 2125 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 2126 } 2127 2128 static inline pid_t task_pid_vnr(struct task_struct *tsk) 2129 { 2130 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 2131 } 2132 2133 2134 static inline pid_t task_tgid_nr(struct task_struct *tsk) 2135 { 2136 return tsk->tgid; 2137 } 2138 2139 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 2140 2141 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 2142 { 2143 return pid_vnr(task_tgid(tsk)); 2144 } 2145 2146 2147 static inline int pid_alive(const struct task_struct *p); 2148 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 2149 { 2150 pid_t pid = 0; 2151 2152 rcu_read_lock(); 2153 if (pid_alive(tsk)) 2154 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 2155 rcu_read_unlock(); 2156 2157 return pid; 2158 } 2159 2160 static inline pid_t task_ppid_nr(const struct task_struct *tsk) 2161 { 2162 return task_ppid_nr_ns(tsk, &init_pid_ns); 2163 } 2164 2165 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 2166 struct pid_namespace *ns) 2167 { 2168 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 2169 } 2170 2171 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 2172 { 2173 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 2174 } 2175 2176 2177 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 2178 struct pid_namespace *ns) 2179 { 2180 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 2181 } 2182 2183 static inline pid_t task_session_vnr(struct task_struct *tsk) 2184 { 2185 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 2186 } 2187 2188 /* obsolete, do not use */ 2189 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 2190 { 2191 return task_pgrp_nr_ns(tsk, &init_pid_ns); 2192 } 2193 2194 /** 2195 * pid_alive - check that a task structure is not stale 2196 * @p: Task structure to be checked. 2197 * 2198 * Test if a process is not yet dead (at most zombie state) 2199 * If pid_alive fails, then pointers within the task structure 2200 * can be stale and must not be dereferenced. 2201 * 2202 * Return: 1 if the process is alive. 0 otherwise. 2203 */ 2204 static inline int pid_alive(const struct task_struct *p) 2205 { 2206 return p->pids[PIDTYPE_PID].pid != NULL; 2207 } 2208 2209 /** 2210 * is_global_init - check if a task structure is init. Since init 2211 * is free to have sub-threads we need to check tgid. 2212 * @tsk: Task structure to be checked. 2213 * 2214 * Check if a task structure is the first user space task the kernel created. 2215 * 2216 * Return: 1 if the task structure is init. 0 otherwise. 2217 */ 2218 static inline int is_global_init(struct task_struct *tsk) 2219 { 2220 return task_tgid_nr(tsk) == 1; 2221 } 2222 2223 extern struct pid *cad_pid; 2224 2225 extern void free_task(struct task_struct *tsk); 2226 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 2227 2228 extern void __put_task_struct(struct task_struct *t); 2229 2230 static inline void put_task_struct(struct task_struct *t) 2231 { 2232 if (atomic_dec_and_test(&t->usage)) 2233 __put_task_struct(t); 2234 } 2235 2236 struct task_struct *task_rcu_dereference(struct task_struct **ptask); 2237 struct task_struct *try_get_task_struct(struct task_struct **ptask); 2238 2239 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 2240 extern void task_cputime(struct task_struct *t, 2241 u64 *utime, u64 *stime); 2242 extern u64 task_gtime(struct task_struct *t); 2243 #else 2244 static inline void task_cputime(struct task_struct *t, 2245 u64 *utime, u64 *stime) 2246 { 2247 *utime = t->utime; 2248 *stime = t->stime; 2249 } 2250 2251 static inline u64 task_gtime(struct task_struct *t) 2252 { 2253 return t->gtime; 2254 } 2255 #endif 2256 2257 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 2258 static inline void task_cputime_scaled(struct task_struct *t, 2259 u64 *utimescaled, 2260 u64 *stimescaled) 2261 { 2262 *utimescaled = t->utimescaled; 2263 *stimescaled = t->stimescaled; 2264 } 2265 #else 2266 static inline void task_cputime_scaled(struct task_struct *t, 2267 u64 *utimescaled, 2268 u64 *stimescaled) 2269 { 2270 task_cputime(t, utimescaled, stimescaled); 2271 } 2272 #endif 2273 2274 extern void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st); 2275 extern void thread_group_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st); 2276 2277 /* 2278 * Per process flags 2279 */ 2280 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 2281 #define PF_EXITING 0x00000004 /* getting shut down */ 2282 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 2283 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 2284 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 2285 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 2286 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 2287 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 2288 #define PF_DUMPCORE 0x00000200 /* dumped core */ 2289 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 2290 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 2291 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 2292 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 2293 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 2294 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 2295 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 2296 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 2297 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 2298 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 2299 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 2300 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 2301 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 2302 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 2303 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 2304 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 2305 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 2306 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 2307 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 2308 2309 /* 2310 * Only the _current_ task can read/write to tsk->flags, but other 2311 * tasks can access tsk->flags in readonly mode for example 2312 * with tsk_used_math (like during threaded core dumping). 2313 * There is however an exception to this rule during ptrace 2314 * or during fork: the ptracer task is allowed to write to the 2315 * child->flags of its traced child (same goes for fork, the parent 2316 * can write to the child->flags), because we're guaranteed the 2317 * child is not running and in turn not changing child->flags 2318 * at the same time the parent does it. 2319 */ 2320 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 2321 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 2322 #define clear_used_math() clear_stopped_child_used_math(current) 2323 #define set_used_math() set_stopped_child_used_math(current) 2324 #define conditional_stopped_child_used_math(condition, child) \ 2325 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 2326 #define conditional_used_math(condition) \ 2327 conditional_stopped_child_used_math(condition, current) 2328 #define copy_to_stopped_child_used_math(child) \ 2329 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 2330 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 2331 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 2332 #define used_math() tsk_used_math(current) 2333 2334 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags 2335 * __GFP_FS is also cleared as it implies __GFP_IO. 2336 */ 2337 static inline gfp_t memalloc_noio_flags(gfp_t flags) 2338 { 2339 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 2340 flags &= ~(__GFP_IO | __GFP_FS); 2341 return flags; 2342 } 2343 2344 static inline unsigned int memalloc_noio_save(void) 2345 { 2346 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 2347 current->flags |= PF_MEMALLOC_NOIO; 2348 return flags; 2349 } 2350 2351 static inline void memalloc_noio_restore(unsigned int flags) 2352 { 2353 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 2354 } 2355 2356 /* Per-process atomic flags. */ 2357 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 2358 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 2359 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 2360 #define PFA_LMK_WAITING 3 /* Lowmemorykiller is waiting */ 2361 2362 2363 #define TASK_PFA_TEST(name, func) \ 2364 static inline bool task_##func(struct task_struct *p) \ 2365 { return test_bit(PFA_##name, &p->atomic_flags); } 2366 #define TASK_PFA_SET(name, func) \ 2367 static inline void task_set_##func(struct task_struct *p) \ 2368 { set_bit(PFA_##name, &p->atomic_flags); } 2369 #define TASK_PFA_CLEAR(name, func) \ 2370 static inline void task_clear_##func(struct task_struct *p) \ 2371 { clear_bit(PFA_##name, &p->atomic_flags); } 2372 2373 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 2374 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 2375 2376 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 2377 TASK_PFA_SET(SPREAD_PAGE, spread_page) 2378 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 2379 2380 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 2381 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 2382 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 2383 2384 TASK_PFA_TEST(LMK_WAITING, lmk_waiting) 2385 TASK_PFA_SET(LMK_WAITING, lmk_waiting) 2386 2387 /* 2388 * task->jobctl flags 2389 */ 2390 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 2391 2392 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 2393 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 2394 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 2395 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 2396 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 2397 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 2398 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 2399 2400 #define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT) 2401 #define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT) 2402 #define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT) 2403 #define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT) 2404 #define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT) 2405 #define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT) 2406 #define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT) 2407 2408 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 2409 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 2410 2411 extern bool task_set_jobctl_pending(struct task_struct *task, 2412 unsigned long mask); 2413 extern void task_clear_jobctl_trapping(struct task_struct *task); 2414 extern void task_clear_jobctl_pending(struct task_struct *task, 2415 unsigned long mask); 2416 2417 static inline void rcu_copy_process(struct task_struct *p) 2418 { 2419 #ifdef CONFIG_PREEMPT_RCU 2420 p->rcu_read_lock_nesting = 0; 2421 p->rcu_read_unlock_special.s = 0; 2422 p->rcu_blocked_node = NULL; 2423 INIT_LIST_HEAD(&p->rcu_node_entry); 2424 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 2425 #ifdef CONFIG_TASKS_RCU 2426 p->rcu_tasks_holdout = false; 2427 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); 2428 p->rcu_tasks_idle_cpu = -1; 2429 #endif /* #ifdef CONFIG_TASKS_RCU */ 2430 } 2431 2432 static inline void tsk_restore_flags(struct task_struct *task, 2433 unsigned long orig_flags, unsigned long flags) 2434 { 2435 task->flags &= ~flags; 2436 task->flags |= orig_flags & flags; 2437 } 2438 2439 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, 2440 const struct cpumask *trial); 2441 extern int task_can_attach(struct task_struct *p, 2442 const struct cpumask *cs_cpus_allowed); 2443 #ifdef CONFIG_SMP 2444 extern void do_set_cpus_allowed(struct task_struct *p, 2445 const struct cpumask *new_mask); 2446 2447 extern int set_cpus_allowed_ptr(struct task_struct *p, 2448 const struct cpumask *new_mask); 2449 #else 2450 static inline void do_set_cpus_allowed(struct task_struct *p, 2451 const struct cpumask *new_mask) 2452 { 2453 } 2454 static inline int set_cpus_allowed_ptr(struct task_struct *p, 2455 const struct cpumask *new_mask) 2456 { 2457 if (!cpumask_test_cpu(0, new_mask)) 2458 return -EINVAL; 2459 return 0; 2460 } 2461 #endif 2462 2463 #ifdef CONFIG_NO_HZ_COMMON 2464 void calc_load_enter_idle(void); 2465 void calc_load_exit_idle(void); 2466 #else 2467 static inline void calc_load_enter_idle(void) { } 2468 static inline void calc_load_exit_idle(void) { } 2469 #endif /* CONFIG_NO_HZ_COMMON */ 2470 2471 #ifndef cpu_relax_yield 2472 #define cpu_relax_yield() cpu_relax() 2473 #endif 2474 2475 /* 2476 * Do not use outside of architecture code which knows its limitations. 2477 * 2478 * sched_clock() has no promise of monotonicity or bounded drift between 2479 * CPUs, use (which you should not) requires disabling IRQs. 2480 * 2481 * Please use one of the three interfaces below. 2482 */ 2483 extern unsigned long long notrace sched_clock(void); 2484 /* 2485 * See the comment in kernel/sched/clock.c 2486 */ 2487 extern u64 running_clock(void); 2488 extern u64 sched_clock_cpu(int cpu); 2489 2490 2491 extern void sched_clock_init(void); 2492 2493 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2494 static inline void sched_clock_init_late(void) 2495 { 2496 } 2497 2498 static inline void sched_clock_tick(void) 2499 { 2500 } 2501 2502 static inline void clear_sched_clock_stable(void) 2503 { 2504 } 2505 2506 static inline void sched_clock_idle_sleep_event(void) 2507 { 2508 } 2509 2510 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 2511 { 2512 } 2513 2514 static inline u64 cpu_clock(int cpu) 2515 { 2516 return sched_clock(); 2517 } 2518 2519 static inline u64 local_clock(void) 2520 { 2521 return sched_clock(); 2522 } 2523 #else 2524 extern void sched_clock_init_late(void); 2525 /* 2526 * Architectures can set this to 1 if they have specified 2527 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 2528 * but then during bootup it turns out that sched_clock() 2529 * is reliable after all: 2530 */ 2531 extern int sched_clock_stable(void); 2532 extern void clear_sched_clock_stable(void); 2533 2534 extern void sched_clock_tick(void); 2535 extern void sched_clock_idle_sleep_event(void); 2536 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2537 2538 /* 2539 * As outlined in clock.c, provides a fast, high resolution, nanosecond 2540 * time source that is monotonic per cpu argument and has bounded drift 2541 * between cpus. 2542 * 2543 * ######################### BIG FAT WARNING ########################## 2544 * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can # 2545 * # go backwards !! # 2546 * #################################################################### 2547 */ 2548 static inline u64 cpu_clock(int cpu) 2549 { 2550 return sched_clock_cpu(cpu); 2551 } 2552 2553 static inline u64 local_clock(void) 2554 { 2555 return sched_clock_cpu(raw_smp_processor_id()); 2556 } 2557 #endif 2558 2559 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2560 /* 2561 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 2562 * The reason for this explicit opt-in is not to have perf penalty with 2563 * slow sched_clocks. 2564 */ 2565 extern void enable_sched_clock_irqtime(void); 2566 extern void disable_sched_clock_irqtime(void); 2567 #else 2568 static inline void enable_sched_clock_irqtime(void) {} 2569 static inline void disable_sched_clock_irqtime(void) {} 2570 #endif 2571 2572 extern unsigned long long 2573 task_sched_runtime(struct task_struct *task); 2574 2575 /* sched_exec is called by processes performing an exec */ 2576 #ifdef CONFIG_SMP 2577 extern void sched_exec(void); 2578 #else 2579 #define sched_exec() {} 2580 #endif 2581 2582 extern void sched_clock_idle_sleep_event(void); 2583 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2584 2585 #ifdef CONFIG_HOTPLUG_CPU 2586 extern void idle_task_exit(void); 2587 #else 2588 static inline void idle_task_exit(void) {} 2589 #endif 2590 2591 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 2592 extern void wake_up_nohz_cpu(int cpu); 2593 #else 2594 static inline void wake_up_nohz_cpu(int cpu) { } 2595 #endif 2596 2597 #ifdef CONFIG_NO_HZ_FULL 2598 extern u64 scheduler_tick_max_deferment(void); 2599 #endif 2600 2601 #ifdef CONFIG_SCHED_AUTOGROUP 2602 extern void sched_autogroup_create_attach(struct task_struct *p); 2603 extern void sched_autogroup_detach(struct task_struct *p); 2604 extern void sched_autogroup_fork(struct signal_struct *sig); 2605 extern void sched_autogroup_exit(struct signal_struct *sig); 2606 extern void sched_autogroup_exit_task(struct task_struct *p); 2607 #ifdef CONFIG_PROC_FS 2608 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2609 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2610 #endif 2611 #else 2612 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2613 static inline void sched_autogroup_detach(struct task_struct *p) { } 2614 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2615 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2616 static inline void sched_autogroup_exit_task(struct task_struct *p) { } 2617 #endif 2618 2619 extern int yield_to(struct task_struct *p, bool preempt); 2620 extern void set_user_nice(struct task_struct *p, long nice); 2621 extern int task_prio(const struct task_struct *p); 2622 /** 2623 * task_nice - return the nice value of a given task. 2624 * @p: the task in question. 2625 * 2626 * Return: The nice value [ -20 ... 0 ... 19 ]. 2627 */ 2628 static inline int task_nice(const struct task_struct *p) 2629 { 2630 return PRIO_TO_NICE((p)->static_prio); 2631 } 2632 extern int can_nice(const struct task_struct *p, const int nice); 2633 extern int task_curr(const struct task_struct *p); 2634 extern int idle_cpu(int cpu); 2635 extern int sched_setscheduler(struct task_struct *, int, 2636 const struct sched_param *); 2637 extern int sched_setscheduler_nocheck(struct task_struct *, int, 2638 const struct sched_param *); 2639 extern int sched_setattr(struct task_struct *, 2640 const struct sched_attr *); 2641 extern struct task_struct *idle_task(int cpu); 2642 /** 2643 * is_idle_task - is the specified task an idle task? 2644 * @p: the task in question. 2645 * 2646 * Return: 1 if @p is an idle task. 0 otherwise. 2647 */ 2648 static inline bool is_idle_task(const struct task_struct *p) 2649 { 2650 return !!(p->flags & PF_IDLE); 2651 } 2652 extern struct task_struct *curr_task(int cpu); 2653 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 2654 2655 void yield(void); 2656 2657 union thread_union { 2658 #ifndef CONFIG_THREAD_INFO_IN_TASK 2659 struct thread_info thread_info; 2660 #endif 2661 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2662 }; 2663 2664 #ifndef __HAVE_ARCH_KSTACK_END 2665 static inline int kstack_end(void *addr) 2666 { 2667 /* Reliable end of stack detection: 2668 * Some APM bios versions misalign the stack 2669 */ 2670 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2671 } 2672 #endif 2673 2674 extern union thread_union init_thread_union; 2675 extern struct task_struct init_task; 2676 2677 extern struct mm_struct init_mm; 2678 2679 extern struct pid_namespace init_pid_ns; 2680 2681 /* 2682 * find a task by one of its numerical ids 2683 * 2684 * find_task_by_pid_ns(): 2685 * finds a task by its pid in the specified namespace 2686 * find_task_by_vpid(): 2687 * finds a task by its virtual pid 2688 * 2689 * see also find_vpid() etc in include/linux/pid.h 2690 */ 2691 2692 extern struct task_struct *find_task_by_vpid(pid_t nr); 2693 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2694 struct pid_namespace *ns); 2695 2696 /* per-UID process charging. */ 2697 extern struct user_struct * alloc_uid(kuid_t); 2698 static inline struct user_struct *get_uid(struct user_struct *u) 2699 { 2700 atomic_inc(&u->__count); 2701 return u; 2702 } 2703 extern void free_uid(struct user_struct *); 2704 2705 #include <asm/current.h> 2706 2707 extern void xtime_update(unsigned long ticks); 2708 2709 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2710 extern int wake_up_process(struct task_struct *tsk); 2711 extern void wake_up_new_task(struct task_struct *tsk); 2712 #ifdef CONFIG_SMP 2713 extern void kick_process(struct task_struct *tsk); 2714 #else 2715 static inline void kick_process(struct task_struct *tsk) { } 2716 #endif 2717 extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 2718 extern void sched_dead(struct task_struct *p); 2719 2720 extern void proc_caches_init(void); 2721 extern void flush_signals(struct task_struct *); 2722 extern void ignore_signals(struct task_struct *); 2723 extern void flush_signal_handlers(struct task_struct *, int force_default); 2724 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2725 2726 static inline int kernel_dequeue_signal(siginfo_t *info) 2727 { 2728 struct task_struct *tsk = current; 2729 siginfo_t __info; 2730 int ret; 2731 2732 spin_lock_irq(&tsk->sighand->siglock); 2733 ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info); 2734 spin_unlock_irq(&tsk->sighand->siglock); 2735 2736 return ret; 2737 } 2738 2739 static inline void kernel_signal_stop(void) 2740 { 2741 spin_lock_irq(¤t->sighand->siglock); 2742 if (current->jobctl & JOBCTL_STOP_DEQUEUED) 2743 __set_current_state(TASK_STOPPED); 2744 spin_unlock_irq(¤t->sighand->siglock); 2745 2746 schedule(); 2747 } 2748 2749 extern void release_task(struct task_struct * p); 2750 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2751 extern int force_sigsegv(int, struct task_struct *); 2752 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2753 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2754 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2755 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2756 const struct cred *, u32); 2757 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2758 extern int kill_pid(struct pid *pid, int sig, int priv); 2759 extern int kill_proc_info(int, struct siginfo *, pid_t); 2760 extern __must_check bool do_notify_parent(struct task_struct *, int); 2761 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2762 extern void force_sig(int, struct task_struct *); 2763 extern int send_sig(int, struct task_struct *, int); 2764 extern int zap_other_threads(struct task_struct *p); 2765 extern struct sigqueue *sigqueue_alloc(void); 2766 extern void sigqueue_free(struct sigqueue *); 2767 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2768 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2769 2770 #ifdef TIF_RESTORE_SIGMASK 2771 /* 2772 * Legacy restore_sigmask accessors. These are inefficient on 2773 * SMP architectures because they require atomic operations. 2774 */ 2775 2776 /** 2777 * set_restore_sigmask() - make sure saved_sigmask processing gets done 2778 * 2779 * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code 2780 * will run before returning to user mode, to process the flag. For 2781 * all callers, TIF_SIGPENDING is already set or it's no harm to set 2782 * it. TIF_RESTORE_SIGMASK need not be in the set of bits that the 2783 * arch code will notice on return to user mode, in case those bits 2784 * are scarce. We set TIF_SIGPENDING here to ensure that the arch 2785 * signal code always gets run when TIF_RESTORE_SIGMASK is set. 2786 */ 2787 static inline void set_restore_sigmask(void) 2788 { 2789 set_thread_flag(TIF_RESTORE_SIGMASK); 2790 WARN_ON(!test_thread_flag(TIF_SIGPENDING)); 2791 } 2792 static inline void clear_restore_sigmask(void) 2793 { 2794 clear_thread_flag(TIF_RESTORE_SIGMASK); 2795 } 2796 static inline bool test_restore_sigmask(void) 2797 { 2798 return test_thread_flag(TIF_RESTORE_SIGMASK); 2799 } 2800 static inline bool test_and_clear_restore_sigmask(void) 2801 { 2802 return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK); 2803 } 2804 2805 #else /* TIF_RESTORE_SIGMASK */ 2806 2807 /* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */ 2808 static inline void set_restore_sigmask(void) 2809 { 2810 current->restore_sigmask = true; 2811 WARN_ON(!test_thread_flag(TIF_SIGPENDING)); 2812 } 2813 static inline void clear_restore_sigmask(void) 2814 { 2815 current->restore_sigmask = false; 2816 } 2817 static inline bool test_restore_sigmask(void) 2818 { 2819 return current->restore_sigmask; 2820 } 2821 static inline bool test_and_clear_restore_sigmask(void) 2822 { 2823 if (!current->restore_sigmask) 2824 return false; 2825 current->restore_sigmask = false; 2826 return true; 2827 } 2828 #endif 2829 2830 static inline void restore_saved_sigmask(void) 2831 { 2832 if (test_and_clear_restore_sigmask()) 2833 __set_current_blocked(¤t->saved_sigmask); 2834 } 2835 2836 static inline sigset_t *sigmask_to_save(void) 2837 { 2838 sigset_t *res = ¤t->blocked; 2839 if (unlikely(test_restore_sigmask())) 2840 res = ¤t->saved_sigmask; 2841 return res; 2842 } 2843 2844 static inline int kill_cad_pid(int sig, int priv) 2845 { 2846 return kill_pid(cad_pid, sig, priv); 2847 } 2848 2849 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2850 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2851 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2852 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2853 2854 /* 2855 * True if we are on the alternate signal stack. 2856 */ 2857 static inline int on_sig_stack(unsigned long sp) 2858 { 2859 /* 2860 * If the signal stack is SS_AUTODISARM then, by construction, we 2861 * can't be on the signal stack unless user code deliberately set 2862 * SS_AUTODISARM when we were already on it. 2863 * 2864 * This improves reliability: if user state gets corrupted such that 2865 * the stack pointer points very close to the end of the signal stack, 2866 * then this check will enable the signal to be handled anyway. 2867 */ 2868 if (current->sas_ss_flags & SS_AUTODISARM) 2869 return 0; 2870 2871 #ifdef CONFIG_STACK_GROWSUP 2872 return sp >= current->sas_ss_sp && 2873 sp - current->sas_ss_sp < current->sas_ss_size; 2874 #else 2875 return sp > current->sas_ss_sp && 2876 sp - current->sas_ss_sp <= current->sas_ss_size; 2877 #endif 2878 } 2879 2880 static inline int sas_ss_flags(unsigned long sp) 2881 { 2882 if (!current->sas_ss_size) 2883 return SS_DISABLE; 2884 2885 return on_sig_stack(sp) ? SS_ONSTACK : 0; 2886 } 2887 2888 static inline void sas_ss_reset(struct task_struct *p) 2889 { 2890 p->sas_ss_sp = 0; 2891 p->sas_ss_size = 0; 2892 p->sas_ss_flags = SS_DISABLE; 2893 } 2894 2895 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2896 { 2897 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2898 #ifdef CONFIG_STACK_GROWSUP 2899 return current->sas_ss_sp; 2900 #else 2901 return current->sas_ss_sp + current->sas_ss_size; 2902 #endif 2903 return sp; 2904 } 2905 2906 /* 2907 * Routines for handling mm_structs 2908 */ 2909 extern struct mm_struct * mm_alloc(void); 2910 2911 /* mmdrop drops the mm and the page tables */ 2912 extern void __mmdrop(struct mm_struct *); 2913 static inline void mmdrop(struct mm_struct *mm) 2914 { 2915 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2916 __mmdrop(mm); 2917 } 2918 2919 static inline void mmdrop_async_fn(struct work_struct *work) 2920 { 2921 struct mm_struct *mm = container_of(work, struct mm_struct, async_put_work); 2922 __mmdrop(mm); 2923 } 2924 2925 static inline void mmdrop_async(struct mm_struct *mm) 2926 { 2927 if (unlikely(atomic_dec_and_test(&mm->mm_count))) { 2928 INIT_WORK(&mm->async_put_work, mmdrop_async_fn); 2929 schedule_work(&mm->async_put_work); 2930 } 2931 } 2932 2933 static inline bool mmget_not_zero(struct mm_struct *mm) 2934 { 2935 return atomic_inc_not_zero(&mm->mm_users); 2936 } 2937 2938 /* mmput gets rid of the mappings and all user-space */ 2939 extern void mmput(struct mm_struct *); 2940 #ifdef CONFIG_MMU 2941 /* same as above but performs the slow path from the async context. Can 2942 * be called from the atomic context as well 2943 */ 2944 extern void mmput_async(struct mm_struct *); 2945 #endif 2946 2947 /* Grab a reference to a task's mm, if it is not already going away */ 2948 extern struct mm_struct *get_task_mm(struct task_struct *task); 2949 /* 2950 * Grab a reference to a task's mm, if it is not already going away 2951 * and ptrace_may_access with the mode parameter passed to it 2952 * succeeds. 2953 */ 2954 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2955 /* Remove the current tasks stale references to the old mm_struct */ 2956 extern void mm_release(struct task_struct *, struct mm_struct *); 2957 2958 #ifdef CONFIG_HAVE_COPY_THREAD_TLS 2959 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, 2960 struct task_struct *, unsigned long); 2961 #else 2962 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2963 struct task_struct *); 2964 2965 /* Architectures that haven't opted into copy_thread_tls get the tls argument 2966 * via pt_regs, so ignore the tls argument passed via C. */ 2967 static inline int copy_thread_tls( 2968 unsigned long clone_flags, unsigned long sp, unsigned long arg, 2969 struct task_struct *p, unsigned long tls) 2970 { 2971 return copy_thread(clone_flags, sp, arg, p); 2972 } 2973 #endif 2974 extern void flush_thread(void); 2975 2976 #ifdef CONFIG_HAVE_EXIT_THREAD 2977 extern void exit_thread(struct task_struct *tsk); 2978 #else 2979 static inline void exit_thread(struct task_struct *tsk) 2980 { 2981 } 2982 #endif 2983 2984 extern void exit_files(struct task_struct *); 2985 extern void __cleanup_sighand(struct sighand_struct *); 2986 2987 extern void exit_itimers(struct signal_struct *); 2988 extern void flush_itimer_signals(void); 2989 2990 extern void do_group_exit(int); 2991 2992 extern int do_execve(struct filename *, 2993 const char __user * const __user *, 2994 const char __user * const __user *); 2995 extern int do_execveat(int, struct filename *, 2996 const char __user * const __user *, 2997 const char __user * const __user *, 2998 int); 2999 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long); 3000 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 3001 struct task_struct *fork_idle(int); 3002 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 3003 3004 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 3005 static inline void set_task_comm(struct task_struct *tsk, const char *from) 3006 { 3007 __set_task_comm(tsk, from, false); 3008 } 3009 extern char *get_task_comm(char *to, struct task_struct *tsk); 3010 3011 #ifdef CONFIG_SMP 3012 void scheduler_ipi(void); 3013 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 3014 #else 3015 static inline void scheduler_ipi(void) { } 3016 static inline unsigned long wait_task_inactive(struct task_struct *p, 3017 long match_state) 3018 { 3019 return 1; 3020 } 3021 #endif 3022 3023 #define tasklist_empty() \ 3024 list_empty(&init_task.tasks) 3025 3026 #define next_task(p) \ 3027 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 3028 3029 #define for_each_process(p) \ 3030 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 3031 3032 extern bool current_is_single_threaded(void); 3033 3034 /* 3035 * Careful: do_each_thread/while_each_thread is a double loop so 3036 * 'break' will not work as expected - use goto instead. 3037 */ 3038 #define do_each_thread(g, t) \ 3039 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 3040 3041 #define while_each_thread(g, t) \ 3042 while ((t = next_thread(t)) != g) 3043 3044 #define __for_each_thread(signal, t) \ 3045 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) 3046 3047 #define for_each_thread(p, t) \ 3048 __for_each_thread((p)->signal, t) 3049 3050 /* Careful: this is a double loop, 'break' won't work as expected. */ 3051 #define for_each_process_thread(p, t) \ 3052 for_each_process(p) for_each_thread(p, t) 3053 3054 static inline int get_nr_threads(struct task_struct *tsk) 3055 { 3056 return tsk->signal->nr_threads; 3057 } 3058 3059 static inline bool thread_group_leader(struct task_struct *p) 3060 { 3061 return p->exit_signal >= 0; 3062 } 3063 3064 /* Do to the insanities of de_thread it is possible for a process 3065 * to have the pid of the thread group leader without actually being 3066 * the thread group leader. For iteration through the pids in proc 3067 * all we care about is that we have a task with the appropriate 3068 * pid, we don't actually care if we have the right task. 3069 */ 3070 static inline bool has_group_leader_pid(struct task_struct *p) 3071 { 3072 return task_pid(p) == p->signal->leader_pid; 3073 } 3074 3075 static inline 3076 bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 3077 { 3078 return p1->signal == p2->signal; 3079 } 3080 3081 static inline struct task_struct *next_thread(const struct task_struct *p) 3082 { 3083 return list_entry_rcu(p->thread_group.next, 3084 struct task_struct, thread_group); 3085 } 3086 3087 static inline int thread_group_empty(struct task_struct *p) 3088 { 3089 return list_empty(&p->thread_group); 3090 } 3091 3092 #define delay_group_leader(p) \ 3093 (thread_group_leader(p) && !thread_group_empty(p)) 3094 3095 /* 3096 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 3097 * subscriptions and synchronises with wait4(). Also used in procfs. Also 3098 * pins the final release of task.io_context. Also protects ->cpuset and 3099 * ->cgroup.subsys[]. And ->vfork_done. 3100 * 3101 * Nests both inside and outside of read_lock(&tasklist_lock). 3102 * It must not be nested with write_lock_irq(&tasklist_lock), 3103 * neither inside nor outside. 3104 */ 3105 static inline void task_lock(struct task_struct *p) 3106 { 3107 spin_lock(&p->alloc_lock); 3108 } 3109 3110 static inline void task_unlock(struct task_struct *p) 3111 { 3112 spin_unlock(&p->alloc_lock); 3113 } 3114 3115 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 3116 unsigned long *flags); 3117 3118 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 3119 unsigned long *flags) 3120 { 3121 struct sighand_struct *ret; 3122 3123 ret = __lock_task_sighand(tsk, flags); 3124 (void)__cond_lock(&tsk->sighand->siglock, ret); 3125 return ret; 3126 } 3127 3128 static inline void unlock_task_sighand(struct task_struct *tsk, 3129 unsigned long *flags) 3130 { 3131 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 3132 } 3133 3134 /** 3135 * threadgroup_change_begin - mark the beginning of changes to a threadgroup 3136 * @tsk: task causing the changes 3137 * 3138 * All operations which modify a threadgroup - a new thread joining the 3139 * group, death of a member thread (the assertion of PF_EXITING) and 3140 * exec(2) dethreading the process and replacing the leader - are wrapped 3141 * by threadgroup_change_{begin|end}(). This is to provide a place which 3142 * subsystems needing threadgroup stability can hook into for 3143 * synchronization. 3144 */ 3145 static inline void threadgroup_change_begin(struct task_struct *tsk) 3146 { 3147 might_sleep(); 3148 cgroup_threadgroup_change_begin(tsk); 3149 } 3150 3151 /** 3152 * threadgroup_change_end - mark the end of changes to a threadgroup 3153 * @tsk: task causing the changes 3154 * 3155 * See threadgroup_change_begin(). 3156 */ 3157 static inline void threadgroup_change_end(struct task_struct *tsk) 3158 { 3159 cgroup_threadgroup_change_end(tsk); 3160 } 3161 3162 #ifdef CONFIG_THREAD_INFO_IN_TASK 3163 3164 static inline struct thread_info *task_thread_info(struct task_struct *task) 3165 { 3166 return &task->thread_info; 3167 } 3168 3169 /* 3170 * When accessing the stack of a non-current task that might exit, use 3171 * try_get_task_stack() instead. task_stack_page will return a pointer 3172 * that could get freed out from under you. 3173 */ 3174 static inline void *task_stack_page(const struct task_struct *task) 3175 { 3176 return task->stack; 3177 } 3178 3179 #define setup_thread_stack(new,old) do { } while(0) 3180 3181 static inline unsigned long *end_of_stack(const struct task_struct *task) 3182 { 3183 return task->stack; 3184 } 3185 3186 #elif !defined(__HAVE_THREAD_FUNCTIONS) 3187 3188 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 3189 #define task_stack_page(task) ((void *)(task)->stack) 3190 3191 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 3192 { 3193 *task_thread_info(p) = *task_thread_info(org); 3194 task_thread_info(p)->task = p; 3195 } 3196 3197 /* 3198 * Return the address of the last usable long on the stack. 3199 * 3200 * When the stack grows down, this is just above the thread 3201 * info struct. Going any lower will corrupt the threadinfo. 3202 * 3203 * When the stack grows up, this is the highest address. 3204 * Beyond that position, we corrupt data on the next page. 3205 */ 3206 static inline unsigned long *end_of_stack(struct task_struct *p) 3207 { 3208 #ifdef CONFIG_STACK_GROWSUP 3209 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1; 3210 #else 3211 return (unsigned long *)(task_thread_info(p) + 1); 3212 #endif 3213 } 3214 3215 #endif 3216 3217 #ifdef CONFIG_THREAD_INFO_IN_TASK 3218 static inline void *try_get_task_stack(struct task_struct *tsk) 3219 { 3220 return atomic_inc_not_zero(&tsk->stack_refcount) ? 3221 task_stack_page(tsk) : NULL; 3222 } 3223 3224 extern void put_task_stack(struct task_struct *tsk); 3225 #else 3226 static inline void *try_get_task_stack(struct task_struct *tsk) 3227 { 3228 return task_stack_page(tsk); 3229 } 3230 3231 static inline void put_task_stack(struct task_struct *tsk) {} 3232 #endif 3233 3234 #define task_stack_end_corrupted(task) \ 3235 (*(end_of_stack(task)) != STACK_END_MAGIC) 3236 3237 static inline int object_is_on_stack(void *obj) 3238 { 3239 void *stack = task_stack_page(current); 3240 3241 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 3242 } 3243 3244 extern void thread_stack_cache_init(void); 3245 3246 #ifdef CONFIG_DEBUG_STACK_USAGE 3247 static inline unsigned long stack_not_used(struct task_struct *p) 3248 { 3249 unsigned long *n = end_of_stack(p); 3250 3251 do { /* Skip over canary */ 3252 # ifdef CONFIG_STACK_GROWSUP 3253 n--; 3254 # else 3255 n++; 3256 # endif 3257 } while (!*n); 3258 3259 # ifdef CONFIG_STACK_GROWSUP 3260 return (unsigned long)end_of_stack(p) - (unsigned long)n; 3261 # else 3262 return (unsigned long)n - (unsigned long)end_of_stack(p); 3263 # endif 3264 } 3265 #endif 3266 extern void set_task_stack_end_magic(struct task_struct *tsk); 3267 3268 /* set thread flags in other task's structures 3269 * - see asm/thread_info.h for TIF_xxxx flags available 3270 */ 3271 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 3272 { 3273 set_ti_thread_flag(task_thread_info(tsk), flag); 3274 } 3275 3276 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 3277 { 3278 clear_ti_thread_flag(task_thread_info(tsk), flag); 3279 } 3280 3281 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 3282 { 3283 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 3284 } 3285 3286 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 3287 { 3288 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 3289 } 3290 3291 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 3292 { 3293 return test_ti_thread_flag(task_thread_info(tsk), flag); 3294 } 3295 3296 static inline void set_tsk_need_resched(struct task_struct *tsk) 3297 { 3298 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 3299 } 3300 3301 static inline void clear_tsk_need_resched(struct task_struct *tsk) 3302 { 3303 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 3304 } 3305 3306 static inline int test_tsk_need_resched(struct task_struct *tsk) 3307 { 3308 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 3309 } 3310 3311 static inline int restart_syscall(void) 3312 { 3313 set_tsk_thread_flag(current, TIF_SIGPENDING); 3314 return -ERESTARTNOINTR; 3315 } 3316 3317 static inline int signal_pending(struct task_struct *p) 3318 { 3319 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 3320 } 3321 3322 static inline int __fatal_signal_pending(struct task_struct *p) 3323 { 3324 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 3325 } 3326 3327 static inline int fatal_signal_pending(struct task_struct *p) 3328 { 3329 return signal_pending(p) && __fatal_signal_pending(p); 3330 } 3331 3332 static inline int signal_pending_state(long state, struct task_struct *p) 3333 { 3334 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 3335 return 0; 3336 if (!signal_pending(p)) 3337 return 0; 3338 3339 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 3340 } 3341 3342 /* 3343 * cond_resched() and cond_resched_lock(): latency reduction via 3344 * explicit rescheduling in places that are safe. The return 3345 * value indicates whether a reschedule was done in fact. 3346 * cond_resched_lock() will drop the spinlock before scheduling, 3347 * cond_resched_softirq() will enable bhs before scheduling. 3348 */ 3349 #ifndef CONFIG_PREEMPT 3350 extern int _cond_resched(void); 3351 #else 3352 static inline int _cond_resched(void) { return 0; } 3353 #endif 3354 3355 #define cond_resched() ({ \ 3356 ___might_sleep(__FILE__, __LINE__, 0); \ 3357 _cond_resched(); \ 3358 }) 3359 3360 extern int __cond_resched_lock(spinlock_t *lock); 3361 3362 #define cond_resched_lock(lock) ({ \ 3363 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 3364 __cond_resched_lock(lock); \ 3365 }) 3366 3367 extern int __cond_resched_softirq(void); 3368 3369 #define cond_resched_softirq() ({ \ 3370 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 3371 __cond_resched_softirq(); \ 3372 }) 3373 3374 static inline void cond_resched_rcu(void) 3375 { 3376 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 3377 rcu_read_unlock(); 3378 cond_resched(); 3379 rcu_read_lock(); 3380 #endif 3381 } 3382 3383 static inline unsigned long get_preempt_disable_ip(struct task_struct *p) 3384 { 3385 #ifdef CONFIG_DEBUG_PREEMPT 3386 return p->preempt_disable_ip; 3387 #else 3388 return 0; 3389 #endif 3390 } 3391 3392 /* 3393 * Does a critical section need to be broken due to another 3394 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 3395 * but a general need for low latency) 3396 */ 3397 static inline int spin_needbreak(spinlock_t *lock) 3398 { 3399 #ifdef CONFIG_PREEMPT 3400 return spin_is_contended(lock); 3401 #else 3402 return 0; 3403 #endif 3404 } 3405 3406 /* 3407 * Idle thread specific functions to determine the need_resched 3408 * polling state. 3409 */ 3410 #ifdef TIF_POLLING_NRFLAG 3411 static inline int tsk_is_polling(struct task_struct *p) 3412 { 3413 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 3414 } 3415 3416 static inline void __current_set_polling(void) 3417 { 3418 set_thread_flag(TIF_POLLING_NRFLAG); 3419 } 3420 3421 static inline bool __must_check current_set_polling_and_test(void) 3422 { 3423 __current_set_polling(); 3424 3425 /* 3426 * Polling state must be visible before we test NEED_RESCHED, 3427 * paired by resched_curr() 3428 */ 3429 smp_mb__after_atomic(); 3430 3431 return unlikely(tif_need_resched()); 3432 } 3433 3434 static inline void __current_clr_polling(void) 3435 { 3436 clear_thread_flag(TIF_POLLING_NRFLAG); 3437 } 3438 3439 static inline bool __must_check current_clr_polling_and_test(void) 3440 { 3441 __current_clr_polling(); 3442 3443 /* 3444 * Polling state must be visible before we test NEED_RESCHED, 3445 * paired by resched_curr() 3446 */ 3447 smp_mb__after_atomic(); 3448 3449 return unlikely(tif_need_resched()); 3450 } 3451 3452 #else 3453 static inline int tsk_is_polling(struct task_struct *p) { return 0; } 3454 static inline void __current_set_polling(void) { } 3455 static inline void __current_clr_polling(void) { } 3456 3457 static inline bool __must_check current_set_polling_and_test(void) 3458 { 3459 return unlikely(tif_need_resched()); 3460 } 3461 static inline bool __must_check current_clr_polling_and_test(void) 3462 { 3463 return unlikely(tif_need_resched()); 3464 } 3465 #endif 3466 3467 static inline void current_clr_polling(void) 3468 { 3469 __current_clr_polling(); 3470 3471 /* 3472 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit. 3473 * Once the bit is cleared, we'll get IPIs with every new 3474 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also 3475 * fold. 3476 */ 3477 smp_mb(); /* paired with resched_curr() */ 3478 3479 preempt_fold_need_resched(); 3480 } 3481 3482 static __always_inline bool need_resched(void) 3483 { 3484 return unlikely(tif_need_resched()); 3485 } 3486 3487 /* 3488 * Thread group CPU time accounting. 3489 */ 3490 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 3491 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 3492 3493 /* 3494 * Reevaluate whether the task has signals pending delivery. 3495 * Wake the task if so. 3496 * This is required every time the blocked sigset_t changes. 3497 * callers must hold sighand->siglock. 3498 */ 3499 extern void recalc_sigpending_and_wake(struct task_struct *t); 3500 extern void recalc_sigpending(void); 3501 3502 extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 3503 3504 static inline void signal_wake_up(struct task_struct *t, bool resume) 3505 { 3506 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 3507 } 3508 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 3509 { 3510 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 3511 } 3512 3513 /* 3514 * Wrappers for p->thread_info->cpu access. No-op on UP. 3515 */ 3516 #ifdef CONFIG_SMP 3517 3518 static inline unsigned int task_cpu(const struct task_struct *p) 3519 { 3520 #ifdef CONFIG_THREAD_INFO_IN_TASK 3521 return p->cpu; 3522 #else 3523 return task_thread_info(p)->cpu; 3524 #endif 3525 } 3526 3527 static inline int task_node(const struct task_struct *p) 3528 { 3529 return cpu_to_node(task_cpu(p)); 3530 } 3531 3532 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 3533 3534 #else 3535 3536 static inline unsigned int task_cpu(const struct task_struct *p) 3537 { 3538 return 0; 3539 } 3540 3541 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 3542 { 3543 } 3544 3545 #endif /* CONFIG_SMP */ 3546 3547 /* 3548 * In order to reduce various lock holder preemption latencies provide an 3549 * interface to see if a vCPU is currently running or not. 3550 * 3551 * This allows us to terminate optimistic spin loops and block, analogous to 3552 * the native optimistic spin heuristic of testing if the lock owner task is 3553 * running or not. 3554 */ 3555 #ifndef vcpu_is_preempted 3556 # define vcpu_is_preempted(cpu) false 3557 #endif 3558 3559 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 3560 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 3561 3562 #ifdef CONFIG_CGROUP_SCHED 3563 extern struct task_group root_task_group; 3564 #endif /* CONFIG_CGROUP_SCHED */ 3565 3566 extern int task_can_switch_user(struct user_struct *up, 3567 struct task_struct *tsk); 3568 3569 #ifdef CONFIG_TASK_XACCT 3570 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3571 { 3572 tsk->ioac.rchar += amt; 3573 } 3574 3575 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3576 { 3577 tsk->ioac.wchar += amt; 3578 } 3579 3580 static inline void inc_syscr(struct task_struct *tsk) 3581 { 3582 tsk->ioac.syscr++; 3583 } 3584 3585 static inline void inc_syscw(struct task_struct *tsk) 3586 { 3587 tsk->ioac.syscw++; 3588 } 3589 #else 3590 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3591 { 3592 } 3593 3594 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3595 { 3596 } 3597 3598 static inline void inc_syscr(struct task_struct *tsk) 3599 { 3600 } 3601 3602 static inline void inc_syscw(struct task_struct *tsk) 3603 { 3604 } 3605 #endif 3606 3607 #ifndef TASK_SIZE_OF 3608 #define TASK_SIZE_OF(tsk) TASK_SIZE 3609 #endif 3610 3611 #ifdef CONFIG_MEMCG 3612 extern void mm_update_next_owner(struct mm_struct *mm); 3613 #else 3614 static inline void mm_update_next_owner(struct mm_struct *mm) 3615 { 3616 } 3617 #endif /* CONFIG_MEMCG */ 3618 3619 static inline unsigned long task_rlimit(const struct task_struct *tsk, 3620 unsigned int limit) 3621 { 3622 return READ_ONCE(tsk->signal->rlim[limit].rlim_cur); 3623 } 3624 3625 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 3626 unsigned int limit) 3627 { 3628 return READ_ONCE(tsk->signal->rlim[limit].rlim_max); 3629 } 3630 3631 static inline unsigned long rlimit(unsigned int limit) 3632 { 3633 return task_rlimit(current, limit); 3634 } 3635 3636 static inline unsigned long rlimit_max(unsigned int limit) 3637 { 3638 return task_rlimit_max(current, limit); 3639 } 3640 3641 #define SCHED_CPUFREQ_RT (1U << 0) 3642 #define SCHED_CPUFREQ_DL (1U << 1) 3643 #define SCHED_CPUFREQ_IOWAIT (1U << 2) 3644 3645 #define SCHED_CPUFREQ_RT_DL (SCHED_CPUFREQ_RT | SCHED_CPUFREQ_DL) 3646 3647 #ifdef CONFIG_CPU_FREQ 3648 struct update_util_data { 3649 void (*func)(struct update_util_data *data, u64 time, unsigned int flags); 3650 }; 3651 3652 void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data, 3653 void (*func)(struct update_util_data *data, u64 time, 3654 unsigned int flags)); 3655 void cpufreq_remove_update_util_hook(int cpu); 3656 #endif /* CONFIG_CPU_FREQ */ 3657 3658 #endif 3659