1 #ifndef _LINUX_SCHED_H 2 #define _LINUX_SCHED_H 3 4 #include <uapi/linux/sched.h> 5 6 #include <linux/sched/prio.h> 7 8 9 struct sched_param { 10 int sched_priority; 11 }; 12 13 #include <asm/param.h> /* for HZ */ 14 15 #include <linux/capability.h> 16 #include <linux/threads.h> 17 #include <linux/kernel.h> 18 #include <linux/types.h> 19 #include <linux/timex.h> 20 #include <linux/jiffies.h> 21 #include <linux/plist.h> 22 #include <linux/rbtree.h> 23 #include <linux/thread_info.h> 24 #include <linux/cpumask.h> 25 #include <linux/errno.h> 26 #include <linux/nodemask.h> 27 #include <linux/mm_types.h> 28 #include <linux/preempt.h> 29 30 #include <asm/page.h> 31 #include <asm/ptrace.h> 32 #include <linux/cputime.h> 33 34 #include <linux/smp.h> 35 #include <linux/sem.h> 36 #include <linux/shm.h> 37 #include <linux/signal.h> 38 #include <linux/compiler.h> 39 #include <linux/completion.h> 40 #include <linux/pid.h> 41 #include <linux/percpu.h> 42 #include <linux/topology.h> 43 #include <linux/seccomp.h> 44 #include <linux/rcupdate.h> 45 #include <linux/rculist.h> 46 #include <linux/rtmutex.h> 47 48 #include <linux/time.h> 49 #include <linux/param.h> 50 #include <linux/resource.h> 51 #include <linux/timer.h> 52 #include <linux/hrtimer.h> 53 #include <linux/kcov.h> 54 #include <linux/task_io_accounting.h> 55 #include <linux/latencytop.h> 56 #include <linux/cred.h> 57 #include <linux/llist.h> 58 #include <linux/uidgid.h> 59 #include <linux/gfp.h> 60 #include <linux/magic.h> 61 #include <linux/cgroup-defs.h> 62 63 #include <asm/processor.h> 64 65 #define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */ 66 67 /* 68 * Extended scheduling parameters data structure. 69 * 70 * This is needed because the original struct sched_param can not be 71 * altered without introducing ABI issues with legacy applications 72 * (e.g., in sched_getparam()). 73 * 74 * However, the possibility of specifying more than just a priority for 75 * the tasks may be useful for a wide variety of application fields, e.g., 76 * multimedia, streaming, automation and control, and many others. 77 * 78 * This variant (sched_attr) is meant at describing a so-called 79 * sporadic time-constrained task. In such model a task is specified by: 80 * - the activation period or minimum instance inter-arrival time; 81 * - the maximum (or average, depending on the actual scheduling 82 * discipline) computation time of all instances, a.k.a. runtime; 83 * - the deadline (relative to the actual activation time) of each 84 * instance. 85 * Very briefly, a periodic (sporadic) task asks for the execution of 86 * some specific computation --which is typically called an instance-- 87 * (at most) every period. Moreover, each instance typically lasts no more 88 * than the runtime and must be completed by time instant t equal to 89 * the instance activation time + the deadline. 90 * 91 * This is reflected by the actual fields of the sched_attr structure: 92 * 93 * @size size of the structure, for fwd/bwd compat. 94 * 95 * @sched_policy task's scheduling policy 96 * @sched_flags for customizing the scheduler behaviour 97 * @sched_nice task's nice value (SCHED_NORMAL/BATCH) 98 * @sched_priority task's static priority (SCHED_FIFO/RR) 99 * @sched_deadline representative of the task's deadline 100 * @sched_runtime representative of the task's runtime 101 * @sched_period representative of the task's period 102 * 103 * Given this task model, there are a multiplicity of scheduling algorithms 104 * and policies, that can be used to ensure all the tasks will make their 105 * timing constraints. 106 * 107 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the 108 * only user of this new interface. More information about the algorithm 109 * available in the scheduling class file or in Documentation/. 110 */ 111 struct sched_attr { 112 u32 size; 113 114 u32 sched_policy; 115 u64 sched_flags; 116 117 /* SCHED_NORMAL, SCHED_BATCH */ 118 s32 sched_nice; 119 120 /* SCHED_FIFO, SCHED_RR */ 121 u32 sched_priority; 122 123 /* SCHED_DEADLINE */ 124 u64 sched_runtime; 125 u64 sched_deadline; 126 u64 sched_period; 127 }; 128 129 struct futex_pi_state; 130 struct robust_list_head; 131 struct bio_list; 132 struct fs_struct; 133 struct perf_event_context; 134 struct blk_plug; 135 struct filename; 136 struct nameidata; 137 138 #define VMACACHE_BITS 2 139 #define VMACACHE_SIZE (1U << VMACACHE_BITS) 140 #define VMACACHE_MASK (VMACACHE_SIZE - 1) 141 142 /* 143 * These are the constant used to fake the fixed-point load-average 144 * counting. Some notes: 145 * - 11 bit fractions expand to 22 bits by the multiplies: this gives 146 * a load-average precision of 10 bits integer + 11 bits fractional 147 * - if you want to count load-averages more often, you need more 148 * precision, or rounding will get you. With 2-second counting freq, 149 * the EXP_n values would be 1981, 2034 and 2043 if still using only 150 * 11 bit fractions. 151 */ 152 extern unsigned long avenrun[]; /* Load averages */ 153 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift); 154 155 #define FSHIFT 11 /* nr of bits of precision */ 156 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */ 157 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */ 158 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */ 159 #define EXP_5 2014 /* 1/exp(5sec/5min) */ 160 #define EXP_15 2037 /* 1/exp(5sec/15min) */ 161 162 #define CALC_LOAD(load,exp,n) \ 163 load *= exp; \ 164 load += n*(FIXED_1-exp); \ 165 load >>= FSHIFT; 166 167 extern unsigned long total_forks; 168 extern int nr_threads; 169 DECLARE_PER_CPU(unsigned long, process_counts); 170 extern int nr_processes(void); 171 extern unsigned long nr_running(void); 172 extern bool single_task_running(void); 173 extern unsigned long nr_iowait(void); 174 extern unsigned long nr_iowait_cpu(int cpu); 175 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load); 176 177 extern void calc_global_load(unsigned long ticks); 178 179 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 180 extern void cpu_load_update_nohz_start(void); 181 extern void cpu_load_update_nohz_stop(void); 182 #else 183 static inline void cpu_load_update_nohz_start(void) { } 184 static inline void cpu_load_update_nohz_stop(void) { } 185 #endif 186 187 extern void dump_cpu_task(int cpu); 188 189 struct seq_file; 190 struct cfs_rq; 191 struct task_group; 192 #ifdef CONFIG_SCHED_DEBUG 193 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); 194 extern void proc_sched_set_task(struct task_struct *p); 195 #endif 196 197 /* 198 * Task state bitmask. NOTE! These bits are also 199 * encoded in fs/proc/array.c: get_task_state(). 200 * 201 * We have two separate sets of flags: task->state 202 * is about runnability, while task->exit_state are 203 * about the task exiting. Confusing, but this way 204 * modifying one set can't modify the other one by 205 * mistake. 206 */ 207 #define TASK_RUNNING 0 208 #define TASK_INTERRUPTIBLE 1 209 #define TASK_UNINTERRUPTIBLE 2 210 #define __TASK_STOPPED 4 211 #define __TASK_TRACED 8 212 /* in tsk->exit_state */ 213 #define EXIT_DEAD 16 214 #define EXIT_ZOMBIE 32 215 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 216 /* in tsk->state again */ 217 #define TASK_DEAD 64 218 #define TASK_WAKEKILL 128 219 #define TASK_WAKING 256 220 #define TASK_PARKED 512 221 #define TASK_NOLOAD 1024 222 #define TASK_NEW 2048 223 #define TASK_STATE_MAX 4096 224 225 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPNn" 226 227 extern char ___assert_task_state[1 - 2*!!( 228 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; 229 230 /* Convenience macros for the sake of set_task_state */ 231 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 232 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 233 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 234 235 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 236 237 /* Convenience macros for the sake of wake_up */ 238 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 239 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) 240 241 /* get_task_state() */ 242 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 243 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 244 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD) 245 246 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) 247 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) 248 #define task_is_stopped_or_traced(task) \ 249 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) 250 #define task_contributes_to_load(task) \ 251 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ 252 (task->flags & PF_FROZEN) == 0 && \ 253 (task->state & TASK_NOLOAD) == 0) 254 255 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 256 257 #define __set_task_state(tsk, state_value) \ 258 do { \ 259 (tsk)->task_state_change = _THIS_IP_; \ 260 (tsk)->state = (state_value); \ 261 } while (0) 262 #define set_task_state(tsk, state_value) \ 263 do { \ 264 (tsk)->task_state_change = _THIS_IP_; \ 265 smp_store_mb((tsk)->state, (state_value)); \ 266 } while (0) 267 268 /* 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 * set_current_state(TASK_UNINTERRUPTIBLE); 274 * if (do_i_need_to_sleep()) 275 * schedule(); 276 * 277 * If the caller does not need such serialisation then use __set_current_state() 278 */ 279 #define __set_current_state(state_value) \ 280 do { \ 281 current->task_state_change = _THIS_IP_; \ 282 current->state = (state_value); \ 283 } while (0) 284 #define set_current_state(state_value) \ 285 do { \ 286 current->task_state_change = _THIS_IP_; \ 287 smp_store_mb(current->state, (state_value)); \ 288 } while (0) 289 290 #else 291 292 #define __set_task_state(tsk, state_value) \ 293 do { (tsk)->state = (state_value); } while (0) 294 #define set_task_state(tsk, state_value) \ 295 smp_store_mb((tsk)->state, (state_value)) 296 297 /* 298 * set_current_state() includes a barrier so that the write of current->state 299 * is correctly serialised wrt the caller's subsequent test of whether to 300 * actually sleep: 301 * 302 * set_current_state(TASK_UNINTERRUPTIBLE); 303 * if (do_i_need_to_sleep()) 304 * schedule(); 305 * 306 * If the caller does not need such serialisation then use __set_current_state() 307 */ 308 #define __set_current_state(state_value) \ 309 do { current->state = (state_value); } while (0) 310 #define set_current_state(state_value) \ 311 smp_store_mb(current->state, (state_value)) 312 313 #endif 314 315 /* Task command name length */ 316 #define TASK_COMM_LEN 16 317 318 #include <linux/spinlock.h> 319 320 /* 321 * This serializes "schedule()" and also protects 322 * the run-queue from deletions/modifications (but 323 * _adding_ to the beginning of the run-queue has 324 * a separate lock). 325 */ 326 extern rwlock_t tasklist_lock; 327 extern spinlock_t mmlist_lock; 328 329 struct task_struct; 330 331 #ifdef CONFIG_PROVE_RCU 332 extern int lockdep_tasklist_lock_is_held(void); 333 #endif /* #ifdef CONFIG_PROVE_RCU */ 334 335 extern void sched_init(void); 336 extern void sched_init_smp(void); 337 extern asmlinkage void schedule_tail(struct task_struct *prev); 338 extern void init_idle(struct task_struct *idle, int cpu); 339 extern void init_idle_bootup_task(struct task_struct *idle); 340 341 extern cpumask_var_t cpu_isolated_map; 342 343 extern int runqueue_is_locked(int cpu); 344 345 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 346 extern void nohz_balance_enter_idle(int cpu); 347 extern void set_cpu_sd_state_idle(void); 348 extern int get_nohz_timer_target(void); 349 #else 350 static inline void nohz_balance_enter_idle(int cpu) { } 351 static inline void set_cpu_sd_state_idle(void) { } 352 #endif 353 354 /* 355 * Only dump TASK_* tasks. (0 for all tasks) 356 */ 357 extern void show_state_filter(unsigned long state_filter); 358 359 static inline void show_state(void) 360 { 361 show_state_filter(0); 362 } 363 364 extern void show_regs(struct pt_regs *); 365 366 /* 367 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current 368 * task), SP is the stack pointer of the first frame that should be shown in the back 369 * trace (or NULL if the entire call-chain of the task should be shown). 370 */ 371 extern void show_stack(struct task_struct *task, unsigned long *sp); 372 373 extern void cpu_init (void); 374 extern void trap_init(void); 375 extern void update_process_times(int user); 376 extern void scheduler_tick(void); 377 extern int sched_cpu_starting(unsigned int cpu); 378 extern int sched_cpu_activate(unsigned int cpu); 379 extern int sched_cpu_deactivate(unsigned int cpu); 380 381 #ifdef CONFIG_HOTPLUG_CPU 382 extern int sched_cpu_dying(unsigned int cpu); 383 #else 384 # define sched_cpu_dying NULL 385 #endif 386 387 extern void sched_show_task(struct task_struct *p); 388 389 #ifdef CONFIG_LOCKUP_DETECTOR 390 extern void touch_softlockup_watchdog_sched(void); 391 extern void touch_softlockup_watchdog(void); 392 extern void touch_softlockup_watchdog_sync(void); 393 extern void touch_all_softlockup_watchdogs(void); 394 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write, 395 void __user *buffer, 396 size_t *lenp, loff_t *ppos); 397 extern unsigned int softlockup_panic; 398 extern unsigned int hardlockup_panic; 399 void lockup_detector_init(void); 400 #else 401 static inline void touch_softlockup_watchdog_sched(void) 402 { 403 } 404 static inline void touch_softlockup_watchdog(void) 405 { 406 } 407 static inline void touch_softlockup_watchdog_sync(void) 408 { 409 } 410 static inline void touch_all_softlockup_watchdogs(void) 411 { 412 } 413 static inline void lockup_detector_init(void) 414 { 415 } 416 #endif 417 418 #ifdef CONFIG_DETECT_HUNG_TASK 419 void reset_hung_task_detector(void); 420 #else 421 static inline void reset_hung_task_detector(void) 422 { 423 } 424 #endif 425 426 /* Attach to any functions which should be ignored in wchan output. */ 427 #define __sched __attribute__((__section__(".sched.text"))) 428 429 /* Linker adds these: start and end of __sched functions */ 430 extern char __sched_text_start[], __sched_text_end[]; 431 432 /* Is this address in the __sched functions? */ 433 extern int in_sched_functions(unsigned long addr); 434 435 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 436 extern signed long schedule_timeout(signed long timeout); 437 extern signed long schedule_timeout_interruptible(signed long timeout); 438 extern signed long schedule_timeout_killable(signed long timeout); 439 extern signed long schedule_timeout_uninterruptible(signed long timeout); 440 extern signed long schedule_timeout_idle(signed long timeout); 441 asmlinkage void schedule(void); 442 extern void schedule_preempt_disabled(void); 443 444 extern long io_schedule_timeout(long timeout); 445 446 static inline void io_schedule(void) 447 { 448 io_schedule_timeout(MAX_SCHEDULE_TIMEOUT); 449 } 450 451 void __noreturn do_task_dead(void); 452 453 struct nsproxy; 454 struct user_namespace; 455 456 #ifdef CONFIG_MMU 457 extern void arch_pick_mmap_layout(struct mm_struct *mm); 458 extern unsigned long 459 arch_get_unmapped_area(struct file *, unsigned long, unsigned long, 460 unsigned long, unsigned long); 461 extern unsigned long 462 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 463 unsigned long len, unsigned long pgoff, 464 unsigned long flags); 465 #else 466 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {} 467 #endif 468 469 #define SUID_DUMP_DISABLE 0 /* No setuid dumping */ 470 #define SUID_DUMP_USER 1 /* Dump as user of process */ 471 #define SUID_DUMP_ROOT 2 /* Dump as root */ 472 473 /* mm flags */ 474 475 /* for SUID_DUMP_* above */ 476 #define MMF_DUMPABLE_BITS 2 477 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1) 478 479 extern void set_dumpable(struct mm_struct *mm, int value); 480 /* 481 * This returns the actual value of the suid_dumpable flag. For things 482 * that are using this for checking for privilege transitions, it must 483 * test against SUID_DUMP_USER rather than treating it as a boolean 484 * value. 485 */ 486 static inline int __get_dumpable(unsigned long mm_flags) 487 { 488 return mm_flags & MMF_DUMPABLE_MASK; 489 } 490 491 static inline int get_dumpable(struct mm_struct *mm) 492 { 493 return __get_dumpable(mm->flags); 494 } 495 496 /* coredump filter bits */ 497 #define MMF_DUMP_ANON_PRIVATE 2 498 #define MMF_DUMP_ANON_SHARED 3 499 #define MMF_DUMP_MAPPED_PRIVATE 4 500 #define MMF_DUMP_MAPPED_SHARED 5 501 #define MMF_DUMP_ELF_HEADERS 6 502 #define MMF_DUMP_HUGETLB_PRIVATE 7 503 #define MMF_DUMP_HUGETLB_SHARED 8 504 #define MMF_DUMP_DAX_PRIVATE 9 505 #define MMF_DUMP_DAX_SHARED 10 506 507 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS 508 #define MMF_DUMP_FILTER_BITS 9 509 #define MMF_DUMP_FILTER_MASK \ 510 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) 511 #define MMF_DUMP_FILTER_DEFAULT \ 512 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\ 513 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF) 514 515 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS 516 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS) 517 #else 518 # define MMF_DUMP_MASK_DEFAULT_ELF 0 519 #endif 520 /* leave room for more dump flags */ 521 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */ 522 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ 523 #define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ 524 525 #define MMF_HAS_UPROBES 19 /* has uprobes */ 526 #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ 527 #define MMF_OOM_SKIP 21 /* mm is of no interest for the OOM killer */ 528 #define MMF_UNSTABLE 22 /* mm is unstable for copy_from_user */ 529 #define MMF_HUGE_ZERO_PAGE 23 /* mm has ever used the global huge zero page */ 530 531 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) 532 533 struct sighand_struct { 534 atomic_t count; 535 struct k_sigaction action[_NSIG]; 536 spinlock_t siglock; 537 wait_queue_head_t signalfd_wqh; 538 }; 539 540 struct pacct_struct { 541 int ac_flag; 542 long ac_exitcode; 543 unsigned long ac_mem; 544 cputime_t ac_utime, ac_stime; 545 unsigned long ac_minflt, ac_majflt; 546 }; 547 548 struct cpu_itimer { 549 cputime_t expires; 550 cputime_t incr; 551 u32 error; 552 u32 incr_error; 553 }; 554 555 /** 556 * struct prev_cputime - snaphsot of system and user cputime 557 * @utime: time spent in user mode 558 * @stime: time spent in system mode 559 * @lock: protects the above two fields 560 * 561 * Stores previous user/system time values such that we can guarantee 562 * monotonicity. 563 */ 564 struct prev_cputime { 565 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 566 cputime_t utime; 567 cputime_t stime; 568 raw_spinlock_t lock; 569 #endif 570 }; 571 572 static inline void prev_cputime_init(struct prev_cputime *prev) 573 { 574 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 575 prev->utime = prev->stime = 0; 576 raw_spin_lock_init(&prev->lock); 577 #endif 578 } 579 580 /** 581 * struct task_cputime - collected CPU time counts 582 * @utime: time spent in user mode, in &cputime_t units 583 * @stime: time spent in kernel mode, in &cputime_t units 584 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds 585 * 586 * This structure groups together three kinds of CPU time that are tracked for 587 * threads and thread groups. Most things considering CPU time want to group 588 * these counts together and treat all three of them in parallel. 589 */ 590 struct task_cputime { 591 cputime_t utime; 592 cputime_t stime; 593 unsigned long long sum_exec_runtime; 594 }; 595 596 /* Alternate field names when used to cache expirations. */ 597 #define virt_exp utime 598 #define prof_exp stime 599 #define sched_exp sum_exec_runtime 600 601 #define INIT_CPUTIME \ 602 (struct task_cputime) { \ 603 .utime = 0, \ 604 .stime = 0, \ 605 .sum_exec_runtime = 0, \ 606 } 607 608 /* 609 * This is the atomic variant of task_cputime, which can be used for 610 * storing and updating task_cputime statistics without locking. 611 */ 612 struct task_cputime_atomic { 613 atomic64_t utime; 614 atomic64_t stime; 615 atomic64_t sum_exec_runtime; 616 }; 617 618 #define INIT_CPUTIME_ATOMIC \ 619 (struct task_cputime_atomic) { \ 620 .utime = ATOMIC64_INIT(0), \ 621 .stime = ATOMIC64_INIT(0), \ 622 .sum_exec_runtime = ATOMIC64_INIT(0), \ 623 } 624 625 #define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) 626 627 /* 628 * Disable preemption until the scheduler is running -- use an unconditional 629 * value so that it also works on !PREEMPT_COUNT kernels. 630 * 631 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count(). 632 */ 633 #define INIT_PREEMPT_COUNT PREEMPT_OFFSET 634 635 /* 636 * Initial preempt_count value; reflects the preempt_count schedule invariant 637 * which states that during context switches: 638 * 639 * preempt_count() == 2*PREEMPT_DISABLE_OFFSET 640 * 641 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels. 642 * Note: See finish_task_switch(). 643 */ 644 #define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) 645 646 /** 647 * struct thread_group_cputimer - thread group interval timer counts 648 * @cputime_atomic: atomic thread group interval timers. 649 * @running: true when there are timers running and 650 * @cputime_atomic receives updates. 651 * @checking_timer: true when a thread in the group is in the 652 * process of checking for thread group timers. 653 * 654 * This structure contains the version of task_cputime, above, that is 655 * used for thread group CPU timer calculations. 656 */ 657 struct thread_group_cputimer { 658 struct task_cputime_atomic cputime_atomic; 659 bool running; 660 bool checking_timer; 661 }; 662 663 #include <linux/rwsem.h> 664 struct autogroup; 665 666 /* 667 * NOTE! "signal_struct" does not have its own 668 * locking, because a shared signal_struct always 669 * implies a shared sighand_struct, so locking 670 * sighand_struct is always a proper superset of 671 * the locking of signal_struct. 672 */ 673 struct signal_struct { 674 atomic_t sigcnt; 675 atomic_t live; 676 int nr_threads; 677 struct list_head thread_head; 678 679 wait_queue_head_t wait_chldexit; /* for wait4() */ 680 681 /* current thread group signal load-balancing target: */ 682 struct task_struct *curr_target; 683 684 /* shared signal handling: */ 685 struct sigpending shared_pending; 686 687 /* thread group exit support */ 688 int group_exit_code; 689 /* overloaded: 690 * - notify group_exit_task when ->count is equal to notify_count 691 * - everyone except group_exit_task is stopped during signal delivery 692 * of fatal signals, group_exit_task processes the signal. 693 */ 694 int notify_count; 695 struct task_struct *group_exit_task; 696 697 /* thread group stop support, overloads group_exit_code too */ 698 int group_stop_count; 699 unsigned int flags; /* see SIGNAL_* flags below */ 700 701 /* 702 * PR_SET_CHILD_SUBREAPER marks a process, like a service 703 * manager, to re-parent orphan (double-forking) child processes 704 * to this process instead of 'init'. The service manager is 705 * able to receive SIGCHLD signals and is able to investigate 706 * the process until it calls wait(). All children of this 707 * process will inherit a flag if they should look for a 708 * child_subreaper process at exit. 709 */ 710 unsigned int is_child_subreaper:1; 711 unsigned int has_child_subreaper:1; 712 713 /* POSIX.1b Interval Timers */ 714 int posix_timer_id; 715 struct list_head posix_timers; 716 717 /* ITIMER_REAL timer for the process */ 718 struct hrtimer real_timer; 719 struct pid *leader_pid; 720 ktime_t it_real_incr; 721 722 /* 723 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use 724 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these 725 * values are defined to 0 and 1 respectively 726 */ 727 struct cpu_itimer it[2]; 728 729 /* 730 * Thread group totals for process CPU timers. 731 * See thread_group_cputimer(), et al, for details. 732 */ 733 struct thread_group_cputimer cputimer; 734 735 /* Earliest-expiration cache. */ 736 struct task_cputime cputime_expires; 737 738 #ifdef CONFIG_NO_HZ_FULL 739 atomic_t tick_dep_mask; 740 #endif 741 742 struct list_head cpu_timers[3]; 743 744 struct pid *tty_old_pgrp; 745 746 /* boolean value for session group leader */ 747 int leader; 748 749 struct tty_struct *tty; /* NULL if no tty */ 750 751 #ifdef CONFIG_SCHED_AUTOGROUP 752 struct autogroup *autogroup; 753 #endif 754 /* 755 * Cumulative resource counters for dead threads in the group, 756 * and for reaped dead child processes forked by this group. 757 * Live threads maintain their own counters and add to these 758 * in __exit_signal, except for the group leader. 759 */ 760 seqlock_t stats_lock; 761 cputime_t utime, stime, cutime, cstime; 762 cputime_t gtime; 763 cputime_t cgtime; 764 struct prev_cputime prev_cputime; 765 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; 766 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; 767 unsigned long inblock, oublock, cinblock, coublock; 768 unsigned long maxrss, cmaxrss; 769 struct task_io_accounting ioac; 770 771 /* 772 * Cumulative ns of schedule CPU time fo dead threads in the 773 * group, not including a zombie group leader, (This only differs 774 * from jiffies_to_ns(utime + stime) if sched_clock uses something 775 * other than jiffies.) 776 */ 777 unsigned long long sum_sched_runtime; 778 779 /* 780 * We don't bother to synchronize most readers of this at all, 781 * because there is no reader checking a limit that actually needs 782 * to get both rlim_cur and rlim_max atomically, and either one 783 * alone is a single word that can safely be read normally. 784 * getrlimit/setrlimit use task_lock(current->group_leader) to 785 * protect this instead of the siglock, because they really 786 * have no need to disable irqs. 787 */ 788 struct rlimit rlim[RLIM_NLIMITS]; 789 790 #ifdef CONFIG_BSD_PROCESS_ACCT 791 struct pacct_struct pacct; /* per-process accounting information */ 792 #endif 793 #ifdef CONFIG_TASKSTATS 794 struct taskstats *stats; 795 #endif 796 #ifdef CONFIG_AUDIT 797 unsigned audit_tty; 798 struct tty_audit_buf *tty_audit_buf; 799 #endif 800 801 /* 802 * Thread is the potential origin of an oom condition; kill first on 803 * oom 804 */ 805 bool oom_flag_origin; 806 short oom_score_adj; /* OOM kill score adjustment */ 807 short oom_score_adj_min; /* OOM kill score adjustment min value. 808 * Only settable by CAP_SYS_RESOURCE. */ 809 struct mm_struct *oom_mm; /* recorded mm when the thread group got 810 * killed by the oom killer */ 811 812 struct mutex cred_guard_mutex; /* guard against foreign influences on 813 * credential calculations 814 * (notably. ptrace) */ 815 }; 816 817 /* 818 * Bits in flags field of signal_struct. 819 */ 820 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ 821 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ 822 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ 823 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ 824 /* 825 * Pending notifications to parent. 826 */ 827 #define SIGNAL_CLD_STOPPED 0x00000010 828 #define SIGNAL_CLD_CONTINUED 0x00000020 829 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) 830 831 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ 832 833 /* If true, all threads except ->group_exit_task have pending SIGKILL */ 834 static inline int signal_group_exit(const struct signal_struct *sig) 835 { 836 return (sig->flags & SIGNAL_GROUP_EXIT) || 837 (sig->group_exit_task != NULL); 838 } 839 840 /* 841 * Some day this will be a full-fledged user tracking system.. 842 */ 843 struct user_struct { 844 atomic_t __count; /* reference count */ 845 atomic_t processes; /* How many processes does this user have? */ 846 atomic_t sigpending; /* How many pending signals does this user have? */ 847 #ifdef CONFIG_INOTIFY_USER 848 atomic_t inotify_watches; /* How many inotify watches does this user have? */ 849 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ 850 #endif 851 #ifdef CONFIG_FANOTIFY 852 atomic_t fanotify_listeners; 853 #endif 854 #ifdef CONFIG_EPOLL 855 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */ 856 #endif 857 #ifdef CONFIG_POSIX_MQUEUE 858 /* protected by mq_lock */ 859 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ 860 #endif 861 unsigned long locked_shm; /* How many pages of mlocked shm ? */ 862 unsigned long unix_inflight; /* How many files in flight in unix sockets */ 863 atomic_long_t pipe_bufs; /* how many pages are allocated in pipe buffers */ 864 865 #ifdef CONFIG_KEYS 866 struct key *uid_keyring; /* UID specific keyring */ 867 struct key *session_keyring; /* UID's default session keyring */ 868 #endif 869 870 /* Hash table maintenance information */ 871 struct hlist_node uidhash_node; 872 kuid_t uid; 873 874 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL) 875 atomic_long_t locked_vm; 876 #endif 877 }; 878 879 extern int uids_sysfs_init(void); 880 881 extern struct user_struct *find_user(kuid_t); 882 883 extern struct user_struct root_user; 884 #define INIT_USER (&root_user) 885 886 887 struct backing_dev_info; 888 struct reclaim_state; 889 890 #ifdef CONFIG_SCHED_INFO 891 struct sched_info { 892 /* cumulative counters */ 893 unsigned long pcount; /* # of times run on this cpu */ 894 unsigned long long run_delay; /* time spent waiting on a runqueue */ 895 896 /* timestamps */ 897 unsigned long long last_arrival,/* when we last ran on a cpu */ 898 last_queued; /* when we were last queued to run */ 899 }; 900 #endif /* CONFIG_SCHED_INFO */ 901 902 #ifdef CONFIG_TASK_DELAY_ACCT 903 struct task_delay_info { 904 spinlock_t lock; 905 unsigned int flags; /* Private per-task flags */ 906 907 /* For each stat XXX, add following, aligned appropriately 908 * 909 * struct timespec XXX_start, XXX_end; 910 * u64 XXX_delay; 911 * u32 XXX_count; 912 * 913 * Atomicity of updates to XXX_delay, XXX_count protected by 914 * single lock above (split into XXX_lock if contention is an issue). 915 */ 916 917 /* 918 * XXX_count is incremented on every XXX operation, the delay 919 * associated with the operation is added to XXX_delay. 920 * XXX_delay contains the accumulated delay time in nanoseconds. 921 */ 922 u64 blkio_start; /* Shared by blkio, swapin */ 923 u64 blkio_delay; /* wait for sync block io completion */ 924 u64 swapin_delay; /* wait for swapin block io completion */ 925 u32 blkio_count; /* total count of the number of sync block */ 926 /* io operations performed */ 927 u32 swapin_count; /* total count of the number of swapin block */ 928 /* io operations performed */ 929 930 u64 freepages_start; 931 u64 freepages_delay; /* wait for memory reclaim */ 932 u32 freepages_count; /* total count of memory reclaim */ 933 }; 934 #endif /* CONFIG_TASK_DELAY_ACCT */ 935 936 static inline int sched_info_on(void) 937 { 938 #ifdef CONFIG_SCHEDSTATS 939 return 1; 940 #elif defined(CONFIG_TASK_DELAY_ACCT) 941 extern int delayacct_on; 942 return delayacct_on; 943 #else 944 return 0; 945 #endif 946 } 947 948 #ifdef CONFIG_SCHEDSTATS 949 void force_schedstat_enabled(void); 950 #endif 951 952 enum cpu_idle_type { 953 CPU_IDLE, 954 CPU_NOT_IDLE, 955 CPU_NEWLY_IDLE, 956 CPU_MAX_IDLE_TYPES 957 }; 958 959 /* 960 * Integer metrics need fixed point arithmetic, e.g., sched/fair 961 * has a few: load, load_avg, util_avg, freq, and capacity. 962 * 963 * We define a basic fixed point arithmetic range, and then formalize 964 * all these metrics based on that basic range. 965 */ 966 # define SCHED_FIXEDPOINT_SHIFT 10 967 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 968 969 /* 970 * Increase resolution of cpu_capacity calculations 971 */ 972 #define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 973 #define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 974 975 /* 976 * Wake-queues are lists of tasks with a pending wakeup, whose 977 * callers have already marked the task as woken internally, 978 * and can thus carry on. A common use case is being able to 979 * do the wakeups once the corresponding user lock as been 980 * released. 981 * 982 * We hold reference to each task in the list across the wakeup, 983 * thus guaranteeing that the memory is still valid by the time 984 * the actual wakeups are performed in wake_up_q(). 985 * 986 * One per task suffices, because there's never a need for a task to be 987 * in two wake queues simultaneously; it is forbidden to abandon a task 988 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is 989 * already in a wake queue, the wakeup will happen soon and the second 990 * waker can just skip it. 991 * 992 * The WAKE_Q macro declares and initializes the list head. 993 * wake_up_q() does NOT reinitialize the list; it's expected to be 994 * called near the end of a function, where the fact that the queue is 995 * not used again will be easy to see by inspection. 996 * 997 * Note that this can cause spurious wakeups. schedule() callers 998 * must ensure the call is done inside a loop, confirming that the 999 * wakeup condition has in fact occurred. 1000 */ 1001 struct wake_q_node { 1002 struct wake_q_node *next; 1003 }; 1004 1005 struct wake_q_head { 1006 struct wake_q_node *first; 1007 struct wake_q_node **lastp; 1008 }; 1009 1010 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01) 1011 1012 #define WAKE_Q(name) \ 1013 struct wake_q_head name = { WAKE_Q_TAIL, &name.first } 1014 1015 extern void wake_q_add(struct wake_q_head *head, 1016 struct task_struct *task); 1017 extern void wake_up_q(struct wake_q_head *head); 1018 1019 /* 1020 * sched-domains (multiprocessor balancing) declarations: 1021 */ 1022 #ifdef CONFIG_SMP 1023 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */ 1024 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */ 1025 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */ 1026 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ 1027 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ 1028 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ 1029 #define SD_ASYM_CPUCAPACITY 0x0040 /* Groups have different max cpu capacities */ 1030 #define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu capacity */ 1031 #define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ 1032 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ 1033 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ 1034 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ 1035 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */ 1036 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */ 1037 #define SD_NUMA 0x4000 /* cross-node balancing */ 1038 1039 #ifdef CONFIG_SCHED_SMT 1040 static inline int cpu_smt_flags(void) 1041 { 1042 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; 1043 } 1044 #endif 1045 1046 #ifdef CONFIG_SCHED_MC 1047 static inline int cpu_core_flags(void) 1048 { 1049 return SD_SHARE_PKG_RESOURCES; 1050 } 1051 #endif 1052 1053 #ifdef CONFIG_NUMA 1054 static inline int cpu_numa_flags(void) 1055 { 1056 return SD_NUMA; 1057 } 1058 #endif 1059 1060 struct sched_domain_attr { 1061 int relax_domain_level; 1062 }; 1063 1064 #define SD_ATTR_INIT (struct sched_domain_attr) { \ 1065 .relax_domain_level = -1, \ 1066 } 1067 1068 extern int sched_domain_level_max; 1069 1070 struct sched_group; 1071 1072 struct sched_domain_shared { 1073 atomic_t ref; 1074 atomic_t nr_busy_cpus; 1075 int has_idle_cores; 1076 }; 1077 1078 struct sched_domain { 1079 /* These fields must be setup */ 1080 struct sched_domain *parent; /* top domain must be null terminated */ 1081 struct sched_domain *child; /* bottom domain must be null terminated */ 1082 struct sched_group *groups; /* the balancing groups of the domain */ 1083 unsigned long min_interval; /* Minimum balance interval ms */ 1084 unsigned long max_interval; /* Maximum balance interval ms */ 1085 unsigned int busy_factor; /* less balancing by factor if busy */ 1086 unsigned int imbalance_pct; /* No balance until over watermark */ 1087 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */ 1088 unsigned int busy_idx; 1089 unsigned int idle_idx; 1090 unsigned int newidle_idx; 1091 unsigned int wake_idx; 1092 unsigned int forkexec_idx; 1093 unsigned int smt_gain; 1094 1095 int nohz_idle; /* NOHZ IDLE status */ 1096 int flags; /* See SD_* */ 1097 int level; 1098 1099 /* Runtime fields. */ 1100 unsigned long last_balance; /* init to jiffies. units in jiffies */ 1101 unsigned int balance_interval; /* initialise to 1. units in ms. */ 1102 unsigned int nr_balance_failed; /* initialise to 0 */ 1103 1104 /* idle_balance() stats */ 1105 u64 max_newidle_lb_cost; 1106 unsigned long next_decay_max_lb_cost; 1107 1108 u64 avg_scan_cost; /* select_idle_sibling */ 1109 1110 #ifdef CONFIG_SCHEDSTATS 1111 /* load_balance() stats */ 1112 unsigned int lb_count[CPU_MAX_IDLE_TYPES]; 1113 unsigned int lb_failed[CPU_MAX_IDLE_TYPES]; 1114 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES]; 1115 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES]; 1116 unsigned int lb_gained[CPU_MAX_IDLE_TYPES]; 1117 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES]; 1118 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES]; 1119 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES]; 1120 1121 /* Active load balancing */ 1122 unsigned int alb_count; 1123 unsigned int alb_failed; 1124 unsigned int alb_pushed; 1125 1126 /* SD_BALANCE_EXEC stats */ 1127 unsigned int sbe_count; 1128 unsigned int sbe_balanced; 1129 unsigned int sbe_pushed; 1130 1131 /* SD_BALANCE_FORK stats */ 1132 unsigned int sbf_count; 1133 unsigned int sbf_balanced; 1134 unsigned int sbf_pushed; 1135 1136 /* try_to_wake_up() stats */ 1137 unsigned int ttwu_wake_remote; 1138 unsigned int ttwu_move_affine; 1139 unsigned int ttwu_move_balance; 1140 #endif 1141 #ifdef CONFIG_SCHED_DEBUG 1142 char *name; 1143 #endif 1144 union { 1145 void *private; /* used during construction */ 1146 struct rcu_head rcu; /* used during destruction */ 1147 }; 1148 struct sched_domain_shared *shared; 1149 1150 unsigned int span_weight; 1151 /* 1152 * Span of all CPUs in this domain. 1153 * 1154 * NOTE: this field is variable length. (Allocated dynamically 1155 * by attaching extra space to the end of the structure, 1156 * depending on how many CPUs the kernel has booted up with) 1157 */ 1158 unsigned long span[0]; 1159 }; 1160 1161 static inline struct cpumask *sched_domain_span(struct sched_domain *sd) 1162 { 1163 return to_cpumask(sd->span); 1164 } 1165 1166 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1167 struct sched_domain_attr *dattr_new); 1168 1169 /* Allocate an array of sched domains, for partition_sched_domains(). */ 1170 cpumask_var_t *alloc_sched_domains(unsigned int ndoms); 1171 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms); 1172 1173 bool cpus_share_cache(int this_cpu, int that_cpu); 1174 1175 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); 1176 typedef int (*sched_domain_flags_f)(void); 1177 1178 #define SDTL_OVERLAP 0x01 1179 1180 struct sd_data { 1181 struct sched_domain **__percpu sd; 1182 struct sched_domain_shared **__percpu sds; 1183 struct sched_group **__percpu sg; 1184 struct sched_group_capacity **__percpu sgc; 1185 }; 1186 1187 struct sched_domain_topology_level { 1188 sched_domain_mask_f mask; 1189 sched_domain_flags_f sd_flags; 1190 int flags; 1191 int numa_level; 1192 struct sd_data data; 1193 #ifdef CONFIG_SCHED_DEBUG 1194 char *name; 1195 #endif 1196 }; 1197 1198 extern void set_sched_topology(struct sched_domain_topology_level *tl); 1199 extern void wake_up_if_idle(int cpu); 1200 1201 #ifdef CONFIG_SCHED_DEBUG 1202 # define SD_INIT_NAME(type) .name = #type 1203 #else 1204 # define SD_INIT_NAME(type) 1205 #endif 1206 1207 #else /* CONFIG_SMP */ 1208 1209 struct sched_domain_attr; 1210 1211 static inline void 1212 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], 1213 struct sched_domain_attr *dattr_new) 1214 { 1215 } 1216 1217 static inline bool cpus_share_cache(int this_cpu, int that_cpu) 1218 { 1219 return true; 1220 } 1221 1222 #endif /* !CONFIG_SMP */ 1223 1224 1225 struct io_context; /* See blkdev.h */ 1226 1227 1228 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK 1229 extern void prefetch_stack(struct task_struct *t); 1230 #else 1231 static inline void prefetch_stack(struct task_struct *t) { } 1232 #endif 1233 1234 struct audit_context; /* See audit.c */ 1235 struct mempolicy; 1236 struct pipe_inode_info; 1237 struct uts_namespace; 1238 1239 struct load_weight { 1240 unsigned long weight; 1241 u32 inv_weight; 1242 }; 1243 1244 /* 1245 * The load_avg/util_avg accumulates an infinite geometric series 1246 * (see __update_load_avg() in kernel/sched/fair.c). 1247 * 1248 * [load_avg definition] 1249 * 1250 * load_avg = runnable% * scale_load_down(load) 1251 * 1252 * where runnable% is the time ratio that a sched_entity is runnable. 1253 * For cfs_rq, it is the aggregated load_avg of all runnable and 1254 * blocked sched_entities. 1255 * 1256 * load_avg may also take frequency scaling into account: 1257 * 1258 * load_avg = runnable% * scale_load_down(load) * freq% 1259 * 1260 * where freq% is the CPU frequency normalized to the highest frequency. 1261 * 1262 * [util_avg definition] 1263 * 1264 * util_avg = running% * SCHED_CAPACITY_SCALE 1265 * 1266 * where running% is the time ratio that a sched_entity is running on 1267 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable 1268 * and blocked sched_entities. 1269 * 1270 * util_avg may also factor frequency scaling and CPU capacity scaling: 1271 * 1272 * util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity% 1273 * 1274 * where freq% is the same as above, and capacity% is the CPU capacity 1275 * normalized to the greatest capacity (due to uarch differences, etc). 1276 * 1277 * N.B., the above ratios (runnable%, running%, freq%, and capacity%) 1278 * themselves are in the range of [0, 1]. To do fixed point arithmetics, 1279 * we therefore scale them to as large a range as necessary. This is for 1280 * example reflected by util_avg's SCHED_CAPACITY_SCALE. 1281 * 1282 * [Overflow issue] 1283 * 1284 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 1285 * with the highest load (=88761), always runnable on a single cfs_rq, 1286 * and should not overflow as the number already hits PID_MAX_LIMIT. 1287 * 1288 * For all other cases (including 32-bit kernels), struct load_weight's 1289 * weight will overflow first before we do, because: 1290 * 1291 * Max(load_avg) <= Max(load.weight) 1292 * 1293 * Then it is the load_weight's responsibility to consider overflow 1294 * issues. 1295 */ 1296 struct sched_avg { 1297 u64 last_update_time, load_sum; 1298 u32 util_sum, period_contrib; 1299 unsigned long load_avg, util_avg; 1300 }; 1301 1302 #ifdef CONFIG_SCHEDSTATS 1303 struct sched_statistics { 1304 u64 wait_start; 1305 u64 wait_max; 1306 u64 wait_count; 1307 u64 wait_sum; 1308 u64 iowait_count; 1309 u64 iowait_sum; 1310 1311 u64 sleep_start; 1312 u64 sleep_max; 1313 s64 sum_sleep_runtime; 1314 1315 u64 block_start; 1316 u64 block_max; 1317 u64 exec_max; 1318 u64 slice_max; 1319 1320 u64 nr_migrations_cold; 1321 u64 nr_failed_migrations_affine; 1322 u64 nr_failed_migrations_running; 1323 u64 nr_failed_migrations_hot; 1324 u64 nr_forced_migrations; 1325 1326 u64 nr_wakeups; 1327 u64 nr_wakeups_sync; 1328 u64 nr_wakeups_migrate; 1329 u64 nr_wakeups_local; 1330 u64 nr_wakeups_remote; 1331 u64 nr_wakeups_affine; 1332 u64 nr_wakeups_affine_attempts; 1333 u64 nr_wakeups_passive; 1334 u64 nr_wakeups_idle; 1335 }; 1336 #endif 1337 1338 struct sched_entity { 1339 struct load_weight load; /* for load-balancing */ 1340 struct rb_node run_node; 1341 struct list_head group_node; 1342 unsigned int on_rq; 1343 1344 u64 exec_start; 1345 u64 sum_exec_runtime; 1346 u64 vruntime; 1347 u64 prev_sum_exec_runtime; 1348 1349 u64 nr_migrations; 1350 1351 #ifdef CONFIG_SCHEDSTATS 1352 struct sched_statistics statistics; 1353 #endif 1354 1355 #ifdef CONFIG_FAIR_GROUP_SCHED 1356 int depth; 1357 struct sched_entity *parent; 1358 /* rq on which this entity is (to be) queued: */ 1359 struct cfs_rq *cfs_rq; 1360 /* rq "owned" by this entity/group: */ 1361 struct cfs_rq *my_q; 1362 #endif 1363 1364 #ifdef CONFIG_SMP 1365 /* 1366 * Per entity load average tracking. 1367 * 1368 * Put into separate cache line so it does not 1369 * collide with read-mostly values above. 1370 */ 1371 struct sched_avg avg ____cacheline_aligned_in_smp; 1372 #endif 1373 }; 1374 1375 struct sched_rt_entity { 1376 struct list_head run_list; 1377 unsigned long timeout; 1378 unsigned long watchdog_stamp; 1379 unsigned int time_slice; 1380 unsigned short on_rq; 1381 unsigned short on_list; 1382 1383 struct sched_rt_entity *back; 1384 #ifdef CONFIG_RT_GROUP_SCHED 1385 struct sched_rt_entity *parent; 1386 /* rq on which this entity is (to be) queued: */ 1387 struct rt_rq *rt_rq; 1388 /* rq "owned" by this entity/group: */ 1389 struct rt_rq *my_q; 1390 #endif 1391 }; 1392 1393 struct sched_dl_entity { 1394 struct rb_node rb_node; 1395 1396 /* 1397 * Original scheduling parameters. Copied here from sched_attr 1398 * during sched_setattr(), they will remain the same until 1399 * the next sched_setattr(). 1400 */ 1401 u64 dl_runtime; /* maximum runtime for each instance */ 1402 u64 dl_deadline; /* relative deadline of each instance */ 1403 u64 dl_period; /* separation of two instances (period) */ 1404 u64 dl_bw; /* dl_runtime / dl_deadline */ 1405 1406 /* 1407 * Actual scheduling parameters. Initialized with the values above, 1408 * they are continously updated during task execution. Note that 1409 * the remaining runtime could be < 0 in case we are in overrun. 1410 */ 1411 s64 runtime; /* remaining runtime for this instance */ 1412 u64 deadline; /* absolute deadline for this instance */ 1413 unsigned int flags; /* specifying the scheduler behaviour */ 1414 1415 /* 1416 * Some bool flags: 1417 * 1418 * @dl_throttled tells if we exhausted the runtime. If so, the 1419 * task has to wait for a replenishment to be performed at the 1420 * next firing of dl_timer. 1421 * 1422 * @dl_boosted tells if we are boosted due to DI. If so we are 1423 * outside bandwidth enforcement mechanism (but only until we 1424 * exit the critical section); 1425 * 1426 * @dl_yielded tells if task gave up the cpu before consuming 1427 * all its available runtime during the last job. 1428 */ 1429 int dl_throttled, dl_boosted, dl_yielded; 1430 1431 /* 1432 * Bandwidth enforcement timer. Each -deadline task has its 1433 * own bandwidth to be enforced, thus we need one timer per task. 1434 */ 1435 struct hrtimer dl_timer; 1436 }; 1437 1438 union rcu_special { 1439 struct { 1440 u8 blocked; 1441 u8 need_qs; 1442 u8 exp_need_qs; 1443 u8 pad; /* Otherwise the compiler can store garbage here. */ 1444 } b; /* Bits. */ 1445 u32 s; /* Set of bits. */ 1446 }; 1447 struct rcu_node; 1448 1449 enum perf_event_task_context { 1450 perf_invalid_context = -1, 1451 perf_hw_context = 0, 1452 perf_sw_context, 1453 perf_nr_task_contexts, 1454 }; 1455 1456 /* Track pages that require TLB flushes */ 1457 struct tlbflush_unmap_batch { 1458 /* 1459 * Each bit set is a CPU that potentially has a TLB entry for one of 1460 * the PFNs being flushed. See set_tlb_ubc_flush_pending(). 1461 */ 1462 struct cpumask cpumask; 1463 1464 /* True if any bit in cpumask is set */ 1465 bool flush_required; 1466 1467 /* 1468 * If true then the PTE was dirty when unmapped. The entry must be 1469 * flushed before IO is initiated or a stale TLB entry potentially 1470 * allows an update without redirtying the page. 1471 */ 1472 bool writable; 1473 }; 1474 1475 struct task_struct { 1476 #ifdef CONFIG_THREAD_INFO_IN_TASK 1477 /* 1478 * For reasons of header soup (see current_thread_info()), this 1479 * must be the first element of task_struct. 1480 */ 1481 struct thread_info thread_info; 1482 #endif 1483 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ 1484 void *stack; 1485 atomic_t usage; 1486 unsigned int flags; /* per process flags, defined below */ 1487 unsigned int ptrace; 1488 1489 #ifdef CONFIG_SMP 1490 struct llist_node wake_entry; 1491 int on_cpu; 1492 #ifdef CONFIG_THREAD_INFO_IN_TASK 1493 unsigned int cpu; /* current CPU */ 1494 #endif 1495 unsigned int wakee_flips; 1496 unsigned long wakee_flip_decay_ts; 1497 struct task_struct *last_wakee; 1498 1499 int wake_cpu; 1500 #endif 1501 int on_rq; 1502 1503 int prio, static_prio, normal_prio; 1504 unsigned int rt_priority; 1505 const struct sched_class *sched_class; 1506 struct sched_entity se; 1507 struct sched_rt_entity rt; 1508 #ifdef CONFIG_CGROUP_SCHED 1509 struct task_group *sched_task_group; 1510 #endif 1511 struct sched_dl_entity dl; 1512 1513 #ifdef CONFIG_PREEMPT_NOTIFIERS 1514 /* list of struct preempt_notifier: */ 1515 struct hlist_head preempt_notifiers; 1516 #endif 1517 1518 #ifdef CONFIG_BLK_DEV_IO_TRACE 1519 unsigned int btrace_seq; 1520 #endif 1521 1522 unsigned int policy; 1523 int nr_cpus_allowed; 1524 cpumask_t cpus_allowed; 1525 1526 #ifdef CONFIG_PREEMPT_RCU 1527 int rcu_read_lock_nesting; 1528 union rcu_special rcu_read_unlock_special; 1529 struct list_head rcu_node_entry; 1530 struct rcu_node *rcu_blocked_node; 1531 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 1532 #ifdef CONFIG_TASKS_RCU 1533 unsigned long rcu_tasks_nvcsw; 1534 bool rcu_tasks_holdout; 1535 struct list_head rcu_tasks_holdout_list; 1536 int rcu_tasks_idle_cpu; 1537 #endif /* #ifdef CONFIG_TASKS_RCU */ 1538 1539 #ifdef CONFIG_SCHED_INFO 1540 struct sched_info sched_info; 1541 #endif 1542 1543 struct list_head tasks; 1544 #ifdef CONFIG_SMP 1545 struct plist_node pushable_tasks; 1546 struct rb_node pushable_dl_tasks; 1547 #endif 1548 1549 struct mm_struct *mm, *active_mm; 1550 /* per-thread vma caching */ 1551 u32 vmacache_seqnum; 1552 struct vm_area_struct *vmacache[VMACACHE_SIZE]; 1553 #if defined(SPLIT_RSS_COUNTING) 1554 struct task_rss_stat rss_stat; 1555 #endif 1556 /* task state */ 1557 int exit_state; 1558 int exit_code, exit_signal; 1559 int pdeath_signal; /* The signal sent when the parent dies */ 1560 unsigned long jobctl; /* JOBCTL_*, siglock protected */ 1561 1562 /* Used for emulating ABI behavior of previous Linux versions */ 1563 unsigned int personality; 1564 1565 /* scheduler bits, serialized by scheduler locks */ 1566 unsigned sched_reset_on_fork:1; 1567 unsigned sched_contributes_to_load:1; 1568 unsigned sched_migrated:1; 1569 unsigned sched_remote_wakeup:1; 1570 unsigned :0; /* force alignment to the next boundary */ 1571 1572 /* unserialized, strictly 'current' */ 1573 unsigned in_execve:1; /* bit to tell LSMs we're in execve */ 1574 unsigned in_iowait:1; 1575 #if !defined(TIF_RESTORE_SIGMASK) 1576 unsigned restore_sigmask:1; 1577 #endif 1578 #ifdef CONFIG_MEMCG 1579 unsigned memcg_may_oom:1; 1580 #ifndef CONFIG_SLOB 1581 unsigned memcg_kmem_skip_account:1; 1582 #endif 1583 #endif 1584 #ifdef CONFIG_COMPAT_BRK 1585 unsigned brk_randomized:1; 1586 #endif 1587 1588 unsigned long atomic_flags; /* Flags needing atomic access. */ 1589 1590 struct restart_block restart_block; 1591 1592 pid_t pid; 1593 pid_t tgid; 1594 1595 #ifdef CONFIG_CC_STACKPROTECTOR 1596 /* Canary value for the -fstack-protector gcc feature */ 1597 unsigned long stack_canary; 1598 #endif 1599 /* 1600 * pointers to (original) parent process, youngest child, younger sibling, 1601 * older sibling, respectively. (p->father can be replaced with 1602 * p->real_parent->pid) 1603 */ 1604 struct task_struct __rcu *real_parent; /* real parent process */ 1605 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */ 1606 /* 1607 * children/sibling forms the list of my natural children 1608 */ 1609 struct list_head children; /* list of my children */ 1610 struct list_head sibling; /* linkage in my parent's children list */ 1611 struct task_struct *group_leader; /* threadgroup leader */ 1612 1613 /* 1614 * ptraced is the list of tasks this task is using ptrace on. 1615 * This includes both natural children and PTRACE_ATTACH targets. 1616 * p->ptrace_entry is p's link on the p->parent->ptraced list. 1617 */ 1618 struct list_head ptraced; 1619 struct list_head ptrace_entry; 1620 1621 /* PID/PID hash table linkage. */ 1622 struct pid_link pids[PIDTYPE_MAX]; 1623 struct list_head thread_group; 1624 struct list_head thread_node; 1625 1626 struct completion *vfork_done; /* for vfork() */ 1627 int __user *set_child_tid; /* CLONE_CHILD_SETTID */ 1628 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ 1629 1630 cputime_t utime, stime, utimescaled, stimescaled; 1631 cputime_t gtime; 1632 struct prev_cputime prev_cputime; 1633 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1634 seqcount_t vtime_seqcount; 1635 unsigned long long vtime_snap; 1636 enum { 1637 /* Task is sleeping or running in a CPU with VTIME inactive */ 1638 VTIME_INACTIVE = 0, 1639 /* Task runs in userspace in a CPU with VTIME active */ 1640 VTIME_USER, 1641 /* Task runs in kernelspace in a CPU with VTIME active */ 1642 VTIME_SYS, 1643 } vtime_snap_whence; 1644 #endif 1645 1646 #ifdef CONFIG_NO_HZ_FULL 1647 atomic_t tick_dep_mask; 1648 #endif 1649 unsigned long nvcsw, nivcsw; /* context switch counts */ 1650 u64 start_time; /* monotonic time in nsec */ 1651 u64 real_start_time; /* boot based time in nsec */ 1652 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */ 1653 unsigned long min_flt, maj_flt; 1654 1655 struct task_cputime cputime_expires; 1656 struct list_head cpu_timers[3]; 1657 1658 /* process credentials */ 1659 const struct cred __rcu *real_cred; /* objective and real subjective task 1660 * credentials (COW) */ 1661 const struct cred __rcu *cred; /* effective (overridable) subjective task 1662 * credentials (COW) */ 1663 char comm[TASK_COMM_LEN]; /* executable name excluding path 1664 - access with [gs]et_task_comm (which lock 1665 it with task_lock()) 1666 - initialized normally by setup_new_exec */ 1667 /* file system info */ 1668 struct nameidata *nameidata; 1669 #ifdef CONFIG_SYSVIPC 1670 /* ipc stuff */ 1671 struct sysv_sem sysvsem; 1672 struct sysv_shm sysvshm; 1673 #endif 1674 #ifdef CONFIG_DETECT_HUNG_TASK 1675 /* hung task detection */ 1676 unsigned long last_switch_count; 1677 #endif 1678 /* filesystem information */ 1679 struct fs_struct *fs; 1680 /* open file information */ 1681 struct files_struct *files; 1682 /* namespaces */ 1683 struct nsproxy *nsproxy; 1684 /* signal handlers */ 1685 struct signal_struct *signal; 1686 struct sighand_struct *sighand; 1687 1688 sigset_t blocked, real_blocked; 1689 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ 1690 struct sigpending pending; 1691 1692 unsigned long sas_ss_sp; 1693 size_t sas_ss_size; 1694 unsigned sas_ss_flags; 1695 1696 struct callback_head *task_works; 1697 1698 struct audit_context *audit_context; 1699 #ifdef CONFIG_AUDITSYSCALL 1700 kuid_t loginuid; 1701 unsigned int sessionid; 1702 #endif 1703 struct seccomp seccomp; 1704 1705 /* Thread group tracking */ 1706 u32 parent_exec_id; 1707 u32 self_exec_id; 1708 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, 1709 * mempolicy */ 1710 spinlock_t alloc_lock; 1711 1712 /* Protection of the PI data structures: */ 1713 raw_spinlock_t pi_lock; 1714 1715 struct wake_q_node wake_q; 1716 1717 #ifdef CONFIG_RT_MUTEXES 1718 /* PI waiters blocked on a rt_mutex held by this task */ 1719 struct rb_root pi_waiters; 1720 struct rb_node *pi_waiters_leftmost; 1721 /* Deadlock detection and priority inheritance handling */ 1722 struct rt_mutex_waiter *pi_blocked_on; 1723 #endif 1724 1725 #ifdef CONFIG_DEBUG_MUTEXES 1726 /* mutex deadlock detection */ 1727 struct mutex_waiter *blocked_on; 1728 #endif 1729 #ifdef CONFIG_TRACE_IRQFLAGS 1730 unsigned int irq_events; 1731 unsigned long hardirq_enable_ip; 1732 unsigned long hardirq_disable_ip; 1733 unsigned int hardirq_enable_event; 1734 unsigned int hardirq_disable_event; 1735 int hardirqs_enabled; 1736 int hardirq_context; 1737 unsigned long softirq_disable_ip; 1738 unsigned long softirq_enable_ip; 1739 unsigned int softirq_disable_event; 1740 unsigned int softirq_enable_event; 1741 int softirqs_enabled; 1742 int softirq_context; 1743 #endif 1744 #ifdef CONFIG_LOCKDEP 1745 # define MAX_LOCK_DEPTH 48UL 1746 u64 curr_chain_key; 1747 int lockdep_depth; 1748 unsigned int lockdep_recursion; 1749 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1750 gfp_t lockdep_reclaim_gfp; 1751 #endif 1752 #ifdef CONFIG_UBSAN 1753 unsigned int in_ubsan; 1754 #endif 1755 1756 /* journalling filesystem info */ 1757 void *journal_info; 1758 1759 /* stacked block device info */ 1760 struct bio_list *bio_list; 1761 1762 #ifdef CONFIG_BLOCK 1763 /* stack plugging */ 1764 struct blk_plug *plug; 1765 #endif 1766 1767 /* VM state */ 1768 struct reclaim_state *reclaim_state; 1769 1770 struct backing_dev_info *backing_dev_info; 1771 1772 struct io_context *io_context; 1773 1774 unsigned long ptrace_message; 1775 siginfo_t *last_siginfo; /* For ptrace use. */ 1776 struct task_io_accounting ioac; 1777 #if defined(CONFIG_TASK_XACCT) 1778 u64 acct_rss_mem1; /* accumulated rss usage */ 1779 u64 acct_vm_mem1; /* accumulated virtual memory usage */ 1780 cputime_t acct_timexpd; /* stime + utime since last update */ 1781 #endif 1782 #ifdef CONFIG_CPUSETS 1783 nodemask_t mems_allowed; /* Protected by alloc_lock */ 1784 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */ 1785 int cpuset_mem_spread_rotor; 1786 int cpuset_slab_spread_rotor; 1787 #endif 1788 #ifdef CONFIG_CGROUPS 1789 /* Control Group info protected by css_set_lock */ 1790 struct css_set __rcu *cgroups; 1791 /* cg_list protected by css_set_lock and tsk->alloc_lock */ 1792 struct list_head cg_list; 1793 #endif 1794 #ifdef CONFIG_FUTEX 1795 struct robust_list_head __user *robust_list; 1796 #ifdef CONFIG_COMPAT 1797 struct compat_robust_list_head __user *compat_robust_list; 1798 #endif 1799 struct list_head pi_state_list; 1800 struct futex_pi_state *pi_state_cache; 1801 #endif 1802 #ifdef CONFIG_PERF_EVENTS 1803 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1804 struct mutex perf_event_mutex; 1805 struct list_head perf_event_list; 1806 #endif 1807 #ifdef CONFIG_DEBUG_PREEMPT 1808 unsigned long preempt_disable_ip; 1809 #endif 1810 #ifdef CONFIG_NUMA 1811 struct mempolicy *mempolicy; /* Protected by alloc_lock */ 1812 short il_next; 1813 short pref_node_fork; 1814 #endif 1815 #ifdef CONFIG_NUMA_BALANCING 1816 int numa_scan_seq; 1817 unsigned int numa_scan_period; 1818 unsigned int numa_scan_period_max; 1819 int numa_preferred_nid; 1820 unsigned long numa_migrate_retry; 1821 u64 node_stamp; /* migration stamp */ 1822 u64 last_task_numa_placement; 1823 u64 last_sum_exec_runtime; 1824 struct callback_head numa_work; 1825 1826 struct list_head numa_entry; 1827 struct numa_group *numa_group; 1828 1829 /* 1830 * numa_faults is an array split into four regions: 1831 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1832 * in this precise order. 1833 * 1834 * faults_memory: Exponential decaying average of faults on a per-node 1835 * basis. Scheduling placement decisions are made based on these 1836 * counts. The values remain static for the duration of a PTE scan. 1837 * faults_cpu: Track the nodes the process was running on when a NUMA 1838 * hinting fault was incurred. 1839 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1840 * during the current scan window. When the scan completes, the counts 1841 * in faults_memory and faults_cpu decay and these values are copied. 1842 */ 1843 unsigned long *numa_faults; 1844 unsigned long total_numa_faults; 1845 1846 /* 1847 * numa_faults_locality tracks if faults recorded during the last 1848 * scan window were remote/local or failed to migrate. The task scan 1849 * period is adapted based on the locality of the faults with different 1850 * weights depending on whether they were shared or private faults 1851 */ 1852 unsigned long numa_faults_locality[3]; 1853 1854 unsigned long numa_pages_migrated; 1855 #endif /* CONFIG_NUMA_BALANCING */ 1856 1857 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 1858 struct tlbflush_unmap_batch tlb_ubc; 1859 #endif 1860 1861 struct rcu_head rcu; 1862 1863 /* 1864 * cache last used pipe for splice 1865 */ 1866 struct pipe_inode_info *splice_pipe; 1867 1868 struct page_frag task_frag; 1869 1870 #ifdef CONFIG_TASK_DELAY_ACCT 1871 struct task_delay_info *delays; 1872 #endif 1873 #ifdef CONFIG_FAULT_INJECTION 1874 int make_it_fail; 1875 #endif 1876 /* 1877 * when (nr_dirtied >= nr_dirtied_pause), it's time to call 1878 * balance_dirty_pages() for some dirty throttling pause 1879 */ 1880 int nr_dirtied; 1881 int nr_dirtied_pause; 1882 unsigned long dirty_paused_when; /* start of a write-and-pause period */ 1883 1884 #ifdef CONFIG_LATENCYTOP 1885 int latency_record_count; 1886 struct latency_record latency_record[LT_SAVECOUNT]; 1887 #endif 1888 /* 1889 * time slack values; these are used to round up poll() and 1890 * select() etc timeout values. These are in nanoseconds. 1891 */ 1892 u64 timer_slack_ns; 1893 u64 default_timer_slack_ns; 1894 1895 #ifdef CONFIG_KASAN 1896 unsigned int kasan_depth; 1897 #endif 1898 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1899 /* Index of current stored address in ret_stack */ 1900 int curr_ret_stack; 1901 /* Stack of return addresses for return function tracing */ 1902 struct ftrace_ret_stack *ret_stack; 1903 /* time stamp for last schedule */ 1904 unsigned long long ftrace_timestamp; 1905 /* 1906 * Number of functions that haven't been traced 1907 * because of depth overrun. 1908 */ 1909 atomic_t trace_overrun; 1910 /* Pause for the tracing */ 1911 atomic_t tracing_graph_pause; 1912 #endif 1913 #ifdef CONFIG_TRACING 1914 /* state flags for use by tracers */ 1915 unsigned long trace; 1916 /* bitmask and counter of trace recursion */ 1917 unsigned long trace_recursion; 1918 #endif /* CONFIG_TRACING */ 1919 #ifdef CONFIG_KCOV 1920 /* Coverage collection mode enabled for this task (0 if disabled). */ 1921 enum kcov_mode kcov_mode; 1922 /* Size of the kcov_area. */ 1923 unsigned kcov_size; 1924 /* Buffer for coverage collection. */ 1925 void *kcov_area; 1926 /* kcov desciptor wired with this task or NULL. */ 1927 struct kcov *kcov; 1928 #endif 1929 #ifdef CONFIG_MEMCG 1930 struct mem_cgroup *memcg_in_oom; 1931 gfp_t memcg_oom_gfp_mask; 1932 int memcg_oom_order; 1933 1934 /* number of pages to reclaim on returning to userland */ 1935 unsigned int memcg_nr_pages_over_high; 1936 #endif 1937 #ifdef CONFIG_UPROBES 1938 struct uprobe_task *utask; 1939 #endif 1940 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1941 unsigned int sequential_io; 1942 unsigned int sequential_io_avg; 1943 #endif 1944 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1945 unsigned long task_state_change; 1946 #endif 1947 int pagefault_disabled; 1948 #ifdef CONFIG_MMU 1949 struct task_struct *oom_reaper_list; 1950 #endif 1951 #ifdef CONFIG_VMAP_STACK 1952 struct vm_struct *stack_vm_area; 1953 #endif 1954 #ifdef CONFIG_THREAD_INFO_IN_TASK 1955 /* A live task holds one reference. */ 1956 atomic_t stack_refcount; 1957 #endif 1958 /* CPU-specific state of this task */ 1959 struct thread_struct thread; 1960 /* 1961 * WARNING: on x86, 'thread_struct' contains a variable-sized 1962 * structure. It *MUST* be at the end of 'task_struct'. 1963 * 1964 * Do not put anything below here! 1965 */ 1966 }; 1967 1968 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT 1969 extern int arch_task_struct_size __read_mostly; 1970 #else 1971 # define arch_task_struct_size (sizeof(struct task_struct)) 1972 #endif 1973 1974 #ifdef CONFIG_VMAP_STACK 1975 static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t) 1976 { 1977 return t->stack_vm_area; 1978 } 1979 #else 1980 static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t) 1981 { 1982 return NULL; 1983 } 1984 #endif 1985 1986 /* Future-safe accessor for struct task_struct's cpus_allowed. */ 1987 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) 1988 1989 static inline int tsk_nr_cpus_allowed(struct task_struct *p) 1990 { 1991 return p->nr_cpus_allowed; 1992 } 1993 1994 #define TNF_MIGRATED 0x01 1995 #define TNF_NO_GROUP 0x02 1996 #define TNF_SHARED 0x04 1997 #define TNF_FAULT_LOCAL 0x08 1998 #define TNF_MIGRATE_FAIL 0x10 1999 2000 static inline bool in_vfork(struct task_struct *tsk) 2001 { 2002 bool ret; 2003 2004 /* 2005 * need RCU to access ->real_parent if CLONE_VM was used along with 2006 * CLONE_PARENT. 2007 * 2008 * We check real_parent->mm == tsk->mm because CLONE_VFORK does not 2009 * imply CLONE_VM 2010 * 2011 * CLONE_VFORK can be used with CLONE_PARENT/CLONE_THREAD and thus 2012 * ->real_parent is not necessarily the task doing vfork(), so in 2013 * theory we can't rely on task_lock() if we want to dereference it. 2014 * 2015 * And in this case we can't trust the real_parent->mm == tsk->mm 2016 * check, it can be false negative. But we do not care, if init or 2017 * another oom-unkillable task does this it should blame itself. 2018 */ 2019 rcu_read_lock(); 2020 ret = tsk->vfork_done && tsk->real_parent->mm == tsk->mm; 2021 rcu_read_unlock(); 2022 2023 return ret; 2024 } 2025 2026 #ifdef CONFIG_NUMA_BALANCING 2027 extern void task_numa_fault(int last_node, int node, int pages, int flags); 2028 extern pid_t task_numa_group_id(struct task_struct *p); 2029 extern void set_numabalancing_state(bool enabled); 2030 extern void task_numa_free(struct task_struct *p); 2031 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page, 2032 int src_nid, int dst_cpu); 2033 #else 2034 static inline void task_numa_fault(int last_node, int node, int pages, 2035 int flags) 2036 { 2037 } 2038 static inline pid_t task_numa_group_id(struct task_struct *p) 2039 { 2040 return 0; 2041 } 2042 static inline void set_numabalancing_state(bool enabled) 2043 { 2044 } 2045 static inline void task_numa_free(struct task_struct *p) 2046 { 2047 } 2048 static inline bool should_numa_migrate_memory(struct task_struct *p, 2049 struct page *page, int src_nid, int dst_cpu) 2050 { 2051 return true; 2052 } 2053 #endif 2054 2055 static inline struct pid *task_pid(struct task_struct *task) 2056 { 2057 return task->pids[PIDTYPE_PID].pid; 2058 } 2059 2060 static inline struct pid *task_tgid(struct task_struct *task) 2061 { 2062 return task->group_leader->pids[PIDTYPE_PID].pid; 2063 } 2064 2065 /* 2066 * Without tasklist or rcu lock it is not safe to dereference 2067 * the result of task_pgrp/task_session even if task == current, 2068 * we can race with another thread doing sys_setsid/sys_setpgid. 2069 */ 2070 static inline struct pid *task_pgrp(struct task_struct *task) 2071 { 2072 return task->group_leader->pids[PIDTYPE_PGID].pid; 2073 } 2074 2075 static inline struct pid *task_session(struct task_struct *task) 2076 { 2077 return task->group_leader->pids[PIDTYPE_SID].pid; 2078 } 2079 2080 struct pid_namespace; 2081 2082 /* 2083 * the helpers to get the task's different pids as they are seen 2084 * from various namespaces 2085 * 2086 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 2087 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 2088 * current. 2089 * task_xid_nr_ns() : id seen from the ns specified; 2090 * 2091 * set_task_vxid() : assigns a virtual id to a task; 2092 * 2093 * see also pid_nr() etc in include/linux/pid.h 2094 */ 2095 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, 2096 struct pid_namespace *ns); 2097 2098 static inline pid_t task_pid_nr(struct task_struct *tsk) 2099 { 2100 return tsk->pid; 2101 } 2102 2103 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, 2104 struct pid_namespace *ns) 2105 { 2106 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 2107 } 2108 2109 static inline pid_t task_pid_vnr(struct task_struct *tsk) 2110 { 2111 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 2112 } 2113 2114 2115 static inline pid_t task_tgid_nr(struct task_struct *tsk) 2116 { 2117 return tsk->tgid; 2118 } 2119 2120 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns); 2121 2122 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 2123 { 2124 return pid_vnr(task_tgid(tsk)); 2125 } 2126 2127 2128 static inline int pid_alive(const struct task_struct *p); 2129 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 2130 { 2131 pid_t pid = 0; 2132 2133 rcu_read_lock(); 2134 if (pid_alive(tsk)) 2135 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 2136 rcu_read_unlock(); 2137 2138 return pid; 2139 } 2140 2141 static inline pid_t task_ppid_nr(const struct task_struct *tsk) 2142 { 2143 return task_ppid_nr_ns(tsk, &init_pid_ns); 2144 } 2145 2146 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, 2147 struct pid_namespace *ns) 2148 { 2149 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 2150 } 2151 2152 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 2153 { 2154 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 2155 } 2156 2157 2158 static inline pid_t task_session_nr_ns(struct task_struct *tsk, 2159 struct pid_namespace *ns) 2160 { 2161 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 2162 } 2163 2164 static inline pid_t task_session_vnr(struct task_struct *tsk) 2165 { 2166 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 2167 } 2168 2169 /* obsolete, do not use */ 2170 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 2171 { 2172 return task_pgrp_nr_ns(tsk, &init_pid_ns); 2173 } 2174 2175 /** 2176 * pid_alive - check that a task structure is not stale 2177 * @p: Task structure to be checked. 2178 * 2179 * Test if a process is not yet dead (at most zombie state) 2180 * If pid_alive fails, then pointers within the task structure 2181 * can be stale and must not be dereferenced. 2182 * 2183 * Return: 1 if the process is alive. 0 otherwise. 2184 */ 2185 static inline int pid_alive(const struct task_struct *p) 2186 { 2187 return p->pids[PIDTYPE_PID].pid != NULL; 2188 } 2189 2190 /** 2191 * is_global_init - check if a task structure is init. Since init 2192 * is free to have sub-threads we need to check tgid. 2193 * @tsk: Task structure to be checked. 2194 * 2195 * Check if a task structure is the first user space task the kernel created. 2196 * 2197 * Return: 1 if the task structure is init. 0 otherwise. 2198 */ 2199 static inline int is_global_init(struct task_struct *tsk) 2200 { 2201 return task_tgid_nr(tsk) == 1; 2202 } 2203 2204 extern struct pid *cad_pid; 2205 2206 extern void free_task(struct task_struct *tsk); 2207 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 2208 2209 extern void __put_task_struct(struct task_struct *t); 2210 2211 static inline void put_task_struct(struct task_struct *t) 2212 { 2213 if (atomic_dec_and_test(&t->usage)) 2214 __put_task_struct(t); 2215 } 2216 2217 struct task_struct *task_rcu_dereference(struct task_struct **ptask); 2218 struct task_struct *try_get_task_struct(struct task_struct **ptask); 2219 2220 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 2221 extern void task_cputime(struct task_struct *t, 2222 cputime_t *utime, cputime_t *stime); 2223 extern void task_cputime_scaled(struct task_struct *t, 2224 cputime_t *utimescaled, cputime_t *stimescaled); 2225 extern cputime_t task_gtime(struct task_struct *t); 2226 #else 2227 static inline void task_cputime(struct task_struct *t, 2228 cputime_t *utime, cputime_t *stime) 2229 { 2230 if (utime) 2231 *utime = t->utime; 2232 if (stime) 2233 *stime = t->stime; 2234 } 2235 2236 static inline void task_cputime_scaled(struct task_struct *t, 2237 cputime_t *utimescaled, 2238 cputime_t *stimescaled) 2239 { 2240 if (utimescaled) 2241 *utimescaled = t->utimescaled; 2242 if (stimescaled) 2243 *stimescaled = t->stimescaled; 2244 } 2245 2246 static inline cputime_t task_gtime(struct task_struct *t) 2247 { 2248 return t->gtime; 2249 } 2250 #endif 2251 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2252 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st); 2253 2254 /* 2255 * Per process flags 2256 */ 2257 #define PF_EXITING 0x00000004 /* getting shut down */ 2258 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ 2259 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ 2260 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 2261 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */ 2262 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */ 2263 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */ 2264 #define PF_DUMPCORE 0x00000200 /* dumped core */ 2265 #define PF_SIGNALED 0x00000400 /* killed by a signal */ 2266 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 2267 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */ 2268 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ 2269 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */ 2270 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ 2271 #define PF_FROZEN 0x00010000 /* frozen for system suspend */ 2272 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */ 2273 #define PF_KSWAPD 0x00040000 /* I am kswapd */ 2274 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */ 2275 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */ 2276 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 2277 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */ 2278 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 2279 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ 2280 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 2281 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ 2282 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 2283 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */ 2284 2285 /* 2286 * Only the _current_ task can read/write to tsk->flags, but other 2287 * tasks can access tsk->flags in readonly mode for example 2288 * with tsk_used_math (like during threaded core dumping). 2289 * There is however an exception to this rule during ptrace 2290 * or during fork: the ptracer task is allowed to write to the 2291 * child->flags of its traced child (same goes for fork, the parent 2292 * can write to the child->flags), because we're guaranteed the 2293 * child is not running and in turn not changing child->flags 2294 * at the same time the parent does it. 2295 */ 2296 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 2297 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 2298 #define clear_used_math() clear_stopped_child_used_math(current) 2299 #define set_used_math() set_stopped_child_used_math(current) 2300 #define conditional_stopped_child_used_math(condition, child) \ 2301 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 2302 #define conditional_used_math(condition) \ 2303 conditional_stopped_child_used_math(condition, current) 2304 #define copy_to_stopped_child_used_math(child) \ 2305 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 2306 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 2307 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 2308 #define used_math() tsk_used_math(current) 2309 2310 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags 2311 * __GFP_FS is also cleared as it implies __GFP_IO. 2312 */ 2313 static inline gfp_t memalloc_noio_flags(gfp_t flags) 2314 { 2315 if (unlikely(current->flags & PF_MEMALLOC_NOIO)) 2316 flags &= ~(__GFP_IO | __GFP_FS); 2317 return flags; 2318 } 2319 2320 static inline unsigned int memalloc_noio_save(void) 2321 { 2322 unsigned int flags = current->flags & PF_MEMALLOC_NOIO; 2323 current->flags |= PF_MEMALLOC_NOIO; 2324 return flags; 2325 } 2326 2327 static inline void memalloc_noio_restore(unsigned int flags) 2328 { 2329 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags; 2330 } 2331 2332 /* Per-process atomic flags. */ 2333 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 2334 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 2335 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 2336 #define PFA_LMK_WAITING 3 /* Lowmemorykiller is waiting */ 2337 2338 2339 #define TASK_PFA_TEST(name, func) \ 2340 static inline bool task_##func(struct task_struct *p) \ 2341 { return test_bit(PFA_##name, &p->atomic_flags); } 2342 #define TASK_PFA_SET(name, func) \ 2343 static inline void task_set_##func(struct task_struct *p) \ 2344 { set_bit(PFA_##name, &p->atomic_flags); } 2345 #define TASK_PFA_CLEAR(name, func) \ 2346 static inline void task_clear_##func(struct task_struct *p) \ 2347 { clear_bit(PFA_##name, &p->atomic_flags); } 2348 2349 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 2350 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 2351 2352 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 2353 TASK_PFA_SET(SPREAD_PAGE, spread_page) 2354 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 2355 2356 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 2357 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 2358 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 2359 2360 TASK_PFA_TEST(LMK_WAITING, lmk_waiting) 2361 TASK_PFA_SET(LMK_WAITING, lmk_waiting) 2362 2363 /* 2364 * task->jobctl flags 2365 */ 2366 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */ 2367 2368 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */ 2369 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */ 2370 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */ 2371 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */ 2372 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */ 2373 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */ 2374 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */ 2375 2376 #define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT) 2377 #define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT) 2378 #define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT) 2379 #define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT) 2380 #define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT) 2381 #define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT) 2382 #define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT) 2383 2384 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY) 2385 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK) 2386 2387 extern bool task_set_jobctl_pending(struct task_struct *task, 2388 unsigned long mask); 2389 extern void task_clear_jobctl_trapping(struct task_struct *task); 2390 extern void task_clear_jobctl_pending(struct task_struct *task, 2391 unsigned long mask); 2392 2393 static inline void rcu_copy_process(struct task_struct *p) 2394 { 2395 #ifdef CONFIG_PREEMPT_RCU 2396 p->rcu_read_lock_nesting = 0; 2397 p->rcu_read_unlock_special.s = 0; 2398 p->rcu_blocked_node = NULL; 2399 INIT_LIST_HEAD(&p->rcu_node_entry); 2400 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 2401 #ifdef CONFIG_TASKS_RCU 2402 p->rcu_tasks_holdout = false; 2403 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list); 2404 p->rcu_tasks_idle_cpu = -1; 2405 #endif /* #ifdef CONFIG_TASKS_RCU */ 2406 } 2407 2408 static inline void tsk_restore_flags(struct task_struct *task, 2409 unsigned long orig_flags, unsigned long flags) 2410 { 2411 task->flags &= ~flags; 2412 task->flags |= orig_flags & flags; 2413 } 2414 2415 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, 2416 const struct cpumask *trial); 2417 extern int task_can_attach(struct task_struct *p, 2418 const struct cpumask *cs_cpus_allowed); 2419 #ifdef CONFIG_SMP 2420 extern void do_set_cpus_allowed(struct task_struct *p, 2421 const struct cpumask *new_mask); 2422 2423 extern int set_cpus_allowed_ptr(struct task_struct *p, 2424 const struct cpumask *new_mask); 2425 #else 2426 static inline void do_set_cpus_allowed(struct task_struct *p, 2427 const struct cpumask *new_mask) 2428 { 2429 } 2430 static inline int set_cpus_allowed_ptr(struct task_struct *p, 2431 const struct cpumask *new_mask) 2432 { 2433 if (!cpumask_test_cpu(0, new_mask)) 2434 return -EINVAL; 2435 return 0; 2436 } 2437 #endif 2438 2439 #ifdef CONFIG_NO_HZ_COMMON 2440 void calc_load_enter_idle(void); 2441 void calc_load_exit_idle(void); 2442 #else 2443 static inline void calc_load_enter_idle(void) { } 2444 static inline void calc_load_exit_idle(void) { } 2445 #endif /* CONFIG_NO_HZ_COMMON */ 2446 2447 /* 2448 * Do not use outside of architecture code which knows its limitations. 2449 * 2450 * sched_clock() has no promise of monotonicity or bounded drift between 2451 * CPUs, use (which you should not) requires disabling IRQs. 2452 * 2453 * Please use one of the three interfaces below. 2454 */ 2455 extern unsigned long long notrace sched_clock(void); 2456 /* 2457 * See the comment in kernel/sched/clock.c 2458 */ 2459 extern u64 running_clock(void); 2460 extern u64 sched_clock_cpu(int cpu); 2461 2462 2463 extern void sched_clock_init(void); 2464 2465 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2466 static inline void sched_clock_tick(void) 2467 { 2468 } 2469 2470 static inline void sched_clock_idle_sleep_event(void) 2471 { 2472 } 2473 2474 static inline void sched_clock_idle_wakeup_event(u64 delta_ns) 2475 { 2476 } 2477 2478 static inline u64 cpu_clock(int cpu) 2479 { 2480 return sched_clock(); 2481 } 2482 2483 static inline u64 local_clock(void) 2484 { 2485 return sched_clock(); 2486 } 2487 #else 2488 /* 2489 * Architectures can set this to 1 if they have specified 2490 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig, 2491 * but then during bootup it turns out that sched_clock() 2492 * is reliable after all: 2493 */ 2494 extern int sched_clock_stable(void); 2495 extern void set_sched_clock_stable(void); 2496 extern void clear_sched_clock_stable(void); 2497 2498 extern void sched_clock_tick(void); 2499 extern void sched_clock_idle_sleep_event(void); 2500 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2501 2502 /* 2503 * As outlined in clock.c, provides a fast, high resolution, nanosecond 2504 * time source that is monotonic per cpu argument and has bounded drift 2505 * between cpus. 2506 * 2507 * ######################### BIG FAT WARNING ########################## 2508 * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can # 2509 * # go backwards !! # 2510 * #################################################################### 2511 */ 2512 static inline u64 cpu_clock(int cpu) 2513 { 2514 return sched_clock_cpu(cpu); 2515 } 2516 2517 static inline u64 local_clock(void) 2518 { 2519 return sched_clock_cpu(raw_smp_processor_id()); 2520 } 2521 #endif 2522 2523 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2524 /* 2525 * An i/f to runtime opt-in for irq time accounting based off of sched_clock. 2526 * The reason for this explicit opt-in is not to have perf penalty with 2527 * slow sched_clocks. 2528 */ 2529 extern void enable_sched_clock_irqtime(void); 2530 extern void disable_sched_clock_irqtime(void); 2531 #else 2532 static inline void enable_sched_clock_irqtime(void) {} 2533 static inline void disable_sched_clock_irqtime(void) {} 2534 #endif 2535 2536 extern unsigned long long 2537 task_sched_runtime(struct task_struct *task); 2538 2539 /* sched_exec is called by processes performing an exec */ 2540 #ifdef CONFIG_SMP 2541 extern void sched_exec(void); 2542 #else 2543 #define sched_exec() {} 2544 #endif 2545 2546 extern void sched_clock_idle_sleep_event(void); 2547 extern void sched_clock_idle_wakeup_event(u64 delta_ns); 2548 2549 #ifdef CONFIG_HOTPLUG_CPU 2550 extern void idle_task_exit(void); 2551 #else 2552 static inline void idle_task_exit(void) {} 2553 #endif 2554 2555 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP) 2556 extern void wake_up_nohz_cpu(int cpu); 2557 #else 2558 static inline void wake_up_nohz_cpu(int cpu) { } 2559 #endif 2560 2561 #ifdef CONFIG_NO_HZ_FULL 2562 extern u64 scheduler_tick_max_deferment(void); 2563 #endif 2564 2565 #ifdef CONFIG_SCHED_AUTOGROUP 2566 extern void sched_autogroup_create_attach(struct task_struct *p); 2567 extern void sched_autogroup_detach(struct task_struct *p); 2568 extern void sched_autogroup_fork(struct signal_struct *sig); 2569 extern void sched_autogroup_exit(struct signal_struct *sig); 2570 extern void sched_autogroup_exit_task(struct task_struct *p); 2571 #ifdef CONFIG_PROC_FS 2572 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); 2573 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice); 2574 #endif 2575 #else 2576 static inline void sched_autogroup_create_attach(struct task_struct *p) { } 2577 static inline void sched_autogroup_detach(struct task_struct *p) { } 2578 static inline void sched_autogroup_fork(struct signal_struct *sig) { } 2579 static inline void sched_autogroup_exit(struct signal_struct *sig) { } 2580 static inline void sched_autogroup_exit_task(struct task_struct *p) { } 2581 #endif 2582 2583 extern int yield_to(struct task_struct *p, bool preempt); 2584 extern void set_user_nice(struct task_struct *p, long nice); 2585 extern int task_prio(const struct task_struct *p); 2586 /** 2587 * task_nice - return the nice value of a given task. 2588 * @p: the task in question. 2589 * 2590 * Return: The nice value [ -20 ... 0 ... 19 ]. 2591 */ 2592 static inline int task_nice(const struct task_struct *p) 2593 { 2594 return PRIO_TO_NICE((p)->static_prio); 2595 } 2596 extern int can_nice(const struct task_struct *p, const int nice); 2597 extern int task_curr(const struct task_struct *p); 2598 extern int idle_cpu(int cpu); 2599 extern int sched_setscheduler(struct task_struct *, int, 2600 const struct sched_param *); 2601 extern int sched_setscheduler_nocheck(struct task_struct *, int, 2602 const struct sched_param *); 2603 extern int sched_setattr(struct task_struct *, 2604 const struct sched_attr *); 2605 extern struct task_struct *idle_task(int cpu); 2606 /** 2607 * is_idle_task - is the specified task an idle task? 2608 * @p: the task in question. 2609 * 2610 * Return: 1 if @p is an idle task. 0 otherwise. 2611 */ 2612 static inline bool is_idle_task(const struct task_struct *p) 2613 { 2614 return p->pid == 0; 2615 } 2616 extern struct task_struct *curr_task(int cpu); 2617 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 2618 2619 void yield(void); 2620 2621 union thread_union { 2622 #ifndef CONFIG_THREAD_INFO_IN_TASK 2623 struct thread_info thread_info; 2624 #endif 2625 unsigned long stack[THREAD_SIZE/sizeof(long)]; 2626 }; 2627 2628 #ifndef __HAVE_ARCH_KSTACK_END 2629 static inline int kstack_end(void *addr) 2630 { 2631 /* Reliable end of stack detection: 2632 * Some APM bios versions misalign the stack 2633 */ 2634 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*))); 2635 } 2636 #endif 2637 2638 extern union thread_union init_thread_union; 2639 extern struct task_struct init_task; 2640 2641 extern struct mm_struct init_mm; 2642 2643 extern struct pid_namespace init_pid_ns; 2644 2645 /* 2646 * find a task by one of its numerical ids 2647 * 2648 * find_task_by_pid_ns(): 2649 * finds a task by its pid in the specified namespace 2650 * find_task_by_vpid(): 2651 * finds a task by its virtual pid 2652 * 2653 * see also find_vpid() etc in include/linux/pid.h 2654 */ 2655 2656 extern struct task_struct *find_task_by_vpid(pid_t nr); 2657 extern struct task_struct *find_task_by_pid_ns(pid_t nr, 2658 struct pid_namespace *ns); 2659 2660 /* per-UID process charging. */ 2661 extern struct user_struct * alloc_uid(kuid_t); 2662 static inline struct user_struct *get_uid(struct user_struct *u) 2663 { 2664 atomic_inc(&u->__count); 2665 return u; 2666 } 2667 extern void free_uid(struct user_struct *); 2668 2669 #include <asm/current.h> 2670 2671 extern void xtime_update(unsigned long ticks); 2672 2673 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 2674 extern int wake_up_process(struct task_struct *tsk); 2675 extern void wake_up_new_task(struct task_struct *tsk); 2676 #ifdef CONFIG_SMP 2677 extern void kick_process(struct task_struct *tsk); 2678 #else 2679 static inline void kick_process(struct task_struct *tsk) { } 2680 #endif 2681 extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 2682 extern void sched_dead(struct task_struct *p); 2683 2684 extern void proc_caches_init(void); 2685 extern void flush_signals(struct task_struct *); 2686 extern void ignore_signals(struct task_struct *); 2687 extern void flush_signal_handlers(struct task_struct *, int force_default); 2688 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); 2689 2690 static inline int kernel_dequeue_signal(siginfo_t *info) 2691 { 2692 struct task_struct *tsk = current; 2693 siginfo_t __info; 2694 int ret; 2695 2696 spin_lock_irq(&tsk->sighand->siglock); 2697 ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info); 2698 spin_unlock_irq(&tsk->sighand->siglock); 2699 2700 return ret; 2701 } 2702 2703 static inline void kernel_signal_stop(void) 2704 { 2705 spin_lock_irq(¤t->sighand->siglock); 2706 if (current->jobctl & JOBCTL_STOP_DEQUEUED) 2707 __set_current_state(TASK_STOPPED); 2708 spin_unlock_irq(¤t->sighand->siglock); 2709 2710 schedule(); 2711 } 2712 2713 extern void release_task(struct task_struct * p); 2714 extern int send_sig_info(int, struct siginfo *, struct task_struct *); 2715 extern int force_sigsegv(int, struct task_struct *); 2716 extern int force_sig_info(int, struct siginfo *, struct task_struct *); 2717 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); 2718 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); 2719 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, 2720 const struct cred *, u32); 2721 extern int kill_pgrp(struct pid *pid, int sig, int priv); 2722 extern int kill_pid(struct pid *pid, int sig, int priv); 2723 extern int kill_proc_info(int, struct siginfo *, pid_t); 2724 extern __must_check bool do_notify_parent(struct task_struct *, int); 2725 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); 2726 extern void force_sig(int, struct task_struct *); 2727 extern int send_sig(int, struct task_struct *, int); 2728 extern int zap_other_threads(struct task_struct *p); 2729 extern struct sigqueue *sigqueue_alloc(void); 2730 extern void sigqueue_free(struct sigqueue *); 2731 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group); 2732 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); 2733 2734 #ifdef TIF_RESTORE_SIGMASK 2735 /* 2736 * Legacy restore_sigmask accessors. These are inefficient on 2737 * SMP architectures because they require atomic operations. 2738 */ 2739 2740 /** 2741 * set_restore_sigmask() - make sure saved_sigmask processing gets done 2742 * 2743 * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code 2744 * will run before returning to user mode, to process the flag. For 2745 * all callers, TIF_SIGPENDING is already set or it's no harm to set 2746 * it. TIF_RESTORE_SIGMASK need not be in the set of bits that the 2747 * arch code will notice on return to user mode, in case those bits 2748 * are scarce. We set TIF_SIGPENDING here to ensure that the arch 2749 * signal code always gets run when TIF_RESTORE_SIGMASK is set. 2750 */ 2751 static inline void set_restore_sigmask(void) 2752 { 2753 set_thread_flag(TIF_RESTORE_SIGMASK); 2754 WARN_ON(!test_thread_flag(TIF_SIGPENDING)); 2755 } 2756 static inline void clear_restore_sigmask(void) 2757 { 2758 clear_thread_flag(TIF_RESTORE_SIGMASK); 2759 } 2760 static inline bool test_restore_sigmask(void) 2761 { 2762 return test_thread_flag(TIF_RESTORE_SIGMASK); 2763 } 2764 static inline bool test_and_clear_restore_sigmask(void) 2765 { 2766 return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK); 2767 } 2768 2769 #else /* TIF_RESTORE_SIGMASK */ 2770 2771 /* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */ 2772 static inline void set_restore_sigmask(void) 2773 { 2774 current->restore_sigmask = true; 2775 WARN_ON(!test_thread_flag(TIF_SIGPENDING)); 2776 } 2777 static inline void clear_restore_sigmask(void) 2778 { 2779 current->restore_sigmask = false; 2780 } 2781 static inline bool test_restore_sigmask(void) 2782 { 2783 return current->restore_sigmask; 2784 } 2785 static inline bool test_and_clear_restore_sigmask(void) 2786 { 2787 if (!current->restore_sigmask) 2788 return false; 2789 current->restore_sigmask = false; 2790 return true; 2791 } 2792 #endif 2793 2794 static inline void restore_saved_sigmask(void) 2795 { 2796 if (test_and_clear_restore_sigmask()) 2797 __set_current_blocked(¤t->saved_sigmask); 2798 } 2799 2800 static inline sigset_t *sigmask_to_save(void) 2801 { 2802 sigset_t *res = ¤t->blocked; 2803 if (unlikely(test_restore_sigmask())) 2804 res = ¤t->saved_sigmask; 2805 return res; 2806 } 2807 2808 static inline int kill_cad_pid(int sig, int priv) 2809 { 2810 return kill_pid(cad_pid, sig, priv); 2811 } 2812 2813 /* These can be the second arg to send_sig_info/send_group_sig_info. */ 2814 #define SEND_SIG_NOINFO ((struct siginfo *) 0) 2815 #define SEND_SIG_PRIV ((struct siginfo *) 1) 2816 #define SEND_SIG_FORCED ((struct siginfo *) 2) 2817 2818 /* 2819 * True if we are on the alternate signal stack. 2820 */ 2821 static inline int on_sig_stack(unsigned long sp) 2822 { 2823 /* 2824 * If the signal stack is SS_AUTODISARM then, by construction, we 2825 * can't be on the signal stack unless user code deliberately set 2826 * SS_AUTODISARM when we were already on it. 2827 * 2828 * This improves reliability: if user state gets corrupted such that 2829 * the stack pointer points very close to the end of the signal stack, 2830 * then this check will enable the signal to be handled anyway. 2831 */ 2832 if (current->sas_ss_flags & SS_AUTODISARM) 2833 return 0; 2834 2835 #ifdef CONFIG_STACK_GROWSUP 2836 return sp >= current->sas_ss_sp && 2837 sp - current->sas_ss_sp < current->sas_ss_size; 2838 #else 2839 return sp > current->sas_ss_sp && 2840 sp - current->sas_ss_sp <= current->sas_ss_size; 2841 #endif 2842 } 2843 2844 static inline int sas_ss_flags(unsigned long sp) 2845 { 2846 if (!current->sas_ss_size) 2847 return SS_DISABLE; 2848 2849 return on_sig_stack(sp) ? SS_ONSTACK : 0; 2850 } 2851 2852 static inline void sas_ss_reset(struct task_struct *p) 2853 { 2854 p->sas_ss_sp = 0; 2855 p->sas_ss_size = 0; 2856 p->sas_ss_flags = SS_DISABLE; 2857 } 2858 2859 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) 2860 { 2861 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) 2862 #ifdef CONFIG_STACK_GROWSUP 2863 return current->sas_ss_sp; 2864 #else 2865 return current->sas_ss_sp + current->sas_ss_size; 2866 #endif 2867 return sp; 2868 } 2869 2870 /* 2871 * Routines for handling mm_structs 2872 */ 2873 extern struct mm_struct * mm_alloc(void); 2874 2875 /* mmdrop drops the mm and the page tables */ 2876 extern void __mmdrop(struct mm_struct *); 2877 static inline void mmdrop(struct mm_struct *mm) 2878 { 2879 if (unlikely(atomic_dec_and_test(&mm->mm_count))) 2880 __mmdrop(mm); 2881 } 2882 2883 static inline void mmdrop_async_fn(struct work_struct *work) 2884 { 2885 struct mm_struct *mm = container_of(work, struct mm_struct, async_put_work); 2886 __mmdrop(mm); 2887 } 2888 2889 static inline void mmdrop_async(struct mm_struct *mm) 2890 { 2891 if (unlikely(atomic_dec_and_test(&mm->mm_count))) { 2892 INIT_WORK(&mm->async_put_work, mmdrop_async_fn); 2893 schedule_work(&mm->async_put_work); 2894 } 2895 } 2896 2897 static inline bool mmget_not_zero(struct mm_struct *mm) 2898 { 2899 return atomic_inc_not_zero(&mm->mm_users); 2900 } 2901 2902 /* mmput gets rid of the mappings and all user-space */ 2903 extern void mmput(struct mm_struct *); 2904 #ifdef CONFIG_MMU 2905 /* same as above but performs the slow path from the async context. Can 2906 * be called from the atomic context as well 2907 */ 2908 extern void mmput_async(struct mm_struct *); 2909 #endif 2910 2911 /* Grab a reference to a task's mm, if it is not already going away */ 2912 extern struct mm_struct *get_task_mm(struct task_struct *task); 2913 /* 2914 * Grab a reference to a task's mm, if it is not already going away 2915 * and ptrace_may_access with the mode parameter passed to it 2916 * succeeds. 2917 */ 2918 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode); 2919 /* Remove the current tasks stale references to the old mm_struct */ 2920 extern void mm_release(struct task_struct *, struct mm_struct *); 2921 2922 #ifdef CONFIG_HAVE_COPY_THREAD_TLS 2923 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, 2924 struct task_struct *, unsigned long); 2925 #else 2926 extern int copy_thread(unsigned long, unsigned long, unsigned long, 2927 struct task_struct *); 2928 2929 /* Architectures that haven't opted into copy_thread_tls get the tls argument 2930 * via pt_regs, so ignore the tls argument passed via C. */ 2931 static inline int copy_thread_tls( 2932 unsigned long clone_flags, unsigned long sp, unsigned long arg, 2933 struct task_struct *p, unsigned long tls) 2934 { 2935 return copy_thread(clone_flags, sp, arg, p); 2936 } 2937 #endif 2938 extern void flush_thread(void); 2939 2940 #ifdef CONFIG_HAVE_EXIT_THREAD 2941 extern void exit_thread(struct task_struct *tsk); 2942 #else 2943 static inline void exit_thread(struct task_struct *tsk) 2944 { 2945 } 2946 #endif 2947 2948 extern void exit_files(struct task_struct *); 2949 extern void __cleanup_sighand(struct sighand_struct *); 2950 2951 extern void exit_itimers(struct signal_struct *); 2952 extern void flush_itimer_signals(void); 2953 2954 extern void do_group_exit(int); 2955 2956 extern int do_execve(struct filename *, 2957 const char __user * const __user *, 2958 const char __user * const __user *); 2959 extern int do_execveat(int, struct filename *, 2960 const char __user * const __user *, 2961 const char __user * const __user *, 2962 int); 2963 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long); 2964 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 2965 struct task_struct *fork_idle(int); 2966 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 2967 2968 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 2969 static inline void set_task_comm(struct task_struct *tsk, const char *from) 2970 { 2971 __set_task_comm(tsk, from, false); 2972 } 2973 extern char *get_task_comm(char *to, struct task_struct *tsk); 2974 2975 #ifdef CONFIG_SMP 2976 void scheduler_ipi(void); 2977 extern unsigned long wait_task_inactive(struct task_struct *, long match_state); 2978 #else 2979 static inline void scheduler_ipi(void) { } 2980 static inline unsigned long wait_task_inactive(struct task_struct *p, 2981 long match_state) 2982 { 2983 return 1; 2984 } 2985 #endif 2986 2987 #define tasklist_empty() \ 2988 list_empty(&init_task.tasks) 2989 2990 #define next_task(p) \ 2991 list_entry_rcu((p)->tasks.next, struct task_struct, tasks) 2992 2993 #define for_each_process(p) \ 2994 for (p = &init_task ; (p = next_task(p)) != &init_task ; ) 2995 2996 extern bool current_is_single_threaded(void); 2997 2998 /* 2999 * Careful: do_each_thread/while_each_thread is a double loop so 3000 * 'break' will not work as expected - use goto instead. 3001 */ 3002 #define do_each_thread(g, t) \ 3003 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do 3004 3005 #define while_each_thread(g, t) \ 3006 while ((t = next_thread(t)) != g) 3007 3008 #define __for_each_thread(signal, t) \ 3009 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) 3010 3011 #define for_each_thread(p, t) \ 3012 __for_each_thread((p)->signal, t) 3013 3014 /* Careful: this is a double loop, 'break' won't work as expected. */ 3015 #define for_each_process_thread(p, t) \ 3016 for_each_process(p) for_each_thread(p, t) 3017 3018 static inline int get_nr_threads(struct task_struct *tsk) 3019 { 3020 return tsk->signal->nr_threads; 3021 } 3022 3023 static inline bool thread_group_leader(struct task_struct *p) 3024 { 3025 return p->exit_signal >= 0; 3026 } 3027 3028 /* Do to the insanities of de_thread it is possible for a process 3029 * to have the pid of the thread group leader without actually being 3030 * the thread group leader. For iteration through the pids in proc 3031 * all we care about is that we have a task with the appropriate 3032 * pid, we don't actually care if we have the right task. 3033 */ 3034 static inline bool has_group_leader_pid(struct task_struct *p) 3035 { 3036 return task_pid(p) == p->signal->leader_pid; 3037 } 3038 3039 static inline 3040 bool same_thread_group(struct task_struct *p1, struct task_struct *p2) 3041 { 3042 return p1->signal == p2->signal; 3043 } 3044 3045 static inline struct task_struct *next_thread(const struct task_struct *p) 3046 { 3047 return list_entry_rcu(p->thread_group.next, 3048 struct task_struct, thread_group); 3049 } 3050 3051 static inline int thread_group_empty(struct task_struct *p) 3052 { 3053 return list_empty(&p->thread_group); 3054 } 3055 3056 #define delay_group_leader(p) \ 3057 (thread_group_leader(p) && !thread_group_empty(p)) 3058 3059 /* 3060 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 3061 * subscriptions and synchronises with wait4(). Also used in procfs. Also 3062 * pins the final release of task.io_context. Also protects ->cpuset and 3063 * ->cgroup.subsys[]. And ->vfork_done. 3064 * 3065 * Nests both inside and outside of read_lock(&tasklist_lock). 3066 * It must not be nested with write_lock_irq(&tasklist_lock), 3067 * neither inside nor outside. 3068 */ 3069 static inline void task_lock(struct task_struct *p) 3070 { 3071 spin_lock(&p->alloc_lock); 3072 } 3073 3074 static inline void task_unlock(struct task_struct *p) 3075 { 3076 spin_unlock(&p->alloc_lock); 3077 } 3078 3079 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, 3080 unsigned long *flags); 3081 3082 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, 3083 unsigned long *flags) 3084 { 3085 struct sighand_struct *ret; 3086 3087 ret = __lock_task_sighand(tsk, flags); 3088 (void)__cond_lock(&tsk->sighand->siglock, ret); 3089 return ret; 3090 } 3091 3092 static inline void unlock_task_sighand(struct task_struct *tsk, 3093 unsigned long *flags) 3094 { 3095 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); 3096 } 3097 3098 /** 3099 * threadgroup_change_begin - mark the beginning of changes to a threadgroup 3100 * @tsk: task causing the changes 3101 * 3102 * All operations which modify a threadgroup - a new thread joining the 3103 * group, death of a member thread (the assertion of PF_EXITING) and 3104 * exec(2) dethreading the process and replacing the leader - are wrapped 3105 * by threadgroup_change_{begin|end}(). This is to provide a place which 3106 * subsystems needing threadgroup stability can hook into for 3107 * synchronization. 3108 */ 3109 static inline void threadgroup_change_begin(struct task_struct *tsk) 3110 { 3111 might_sleep(); 3112 cgroup_threadgroup_change_begin(tsk); 3113 } 3114 3115 /** 3116 * threadgroup_change_end - mark the end of changes to a threadgroup 3117 * @tsk: task causing the changes 3118 * 3119 * See threadgroup_change_begin(). 3120 */ 3121 static inline void threadgroup_change_end(struct task_struct *tsk) 3122 { 3123 cgroup_threadgroup_change_end(tsk); 3124 } 3125 3126 #ifdef CONFIG_THREAD_INFO_IN_TASK 3127 3128 static inline struct thread_info *task_thread_info(struct task_struct *task) 3129 { 3130 return &task->thread_info; 3131 } 3132 3133 /* 3134 * When accessing the stack of a non-current task that might exit, use 3135 * try_get_task_stack() instead. task_stack_page will return a pointer 3136 * that could get freed out from under you. 3137 */ 3138 static inline void *task_stack_page(const struct task_struct *task) 3139 { 3140 return task->stack; 3141 } 3142 3143 #define setup_thread_stack(new,old) do { } while(0) 3144 3145 static inline unsigned long *end_of_stack(const struct task_struct *task) 3146 { 3147 return task->stack; 3148 } 3149 3150 #elif !defined(__HAVE_THREAD_FUNCTIONS) 3151 3152 #define task_thread_info(task) ((struct thread_info *)(task)->stack) 3153 #define task_stack_page(task) ((void *)(task)->stack) 3154 3155 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) 3156 { 3157 *task_thread_info(p) = *task_thread_info(org); 3158 task_thread_info(p)->task = p; 3159 } 3160 3161 /* 3162 * Return the address of the last usable long on the stack. 3163 * 3164 * When the stack grows down, this is just above the thread 3165 * info struct. Going any lower will corrupt the threadinfo. 3166 * 3167 * When the stack grows up, this is the highest address. 3168 * Beyond that position, we corrupt data on the next page. 3169 */ 3170 static inline unsigned long *end_of_stack(struct task_struct *p) 3171 { 3172 #ifdef CONFIG_STACK_GROWSUP 3173 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1; 3174 #else 3175 return (unsigned long *)(task_thread_info(p) + 1); 3176 #endif 3177 } 3178 3179 #endif 3180 3181 #ifdef CONFIG_THREAD_INFO_IN_TASK 3182 static inline void *try_get_task_stack(struct task_struct *tsk) 3183 { 3184 return atomic_inc_not_zero(&tsk->stack_refcount) ? 3185 task_stack_page(tsk) : NULL; 3186 } 3187 3188 extern void put_task_stack(struct task_struct *tsk); 3189 #else 3190 static inline void *try_get_task_stack(struct task_struct *tsk) 3191 { 3192 return task_stack_page(tsk); 3193 } 3194 3195 static inline void put_task_stack(struct task_struct *tsk) {} 3196 #endif 3197 3198 #define task_stack_end_corrupted(task) \ 3199 (*(end_of_stack(task)) != STACK_END_MAGIC) 3200 3201 static inline int object_is_on_stack(void *obj) 3202 { 3203 void *stack = task_stack_page(current); 3204 3205 return (obj >= stack) && (obj < (stack + THREAD_SIZE)); 3206 } 3207 3208 extern void thread_stack_cache_init(void); 3209 3210 #ifdef CONFIG_DEBUG_STACK_USAGE 3211 static inline unsigned long stack_not_used(struct task_struct *p) 3212 { 3213 unsigned long *n = end_of_stack(p); 3214 3215 do { /* Skip over canary */ 3216 # ifdef CONFIG_STACK_GROWSUP 3217 n--; 3218 # else 3219 n++; 3220 # endif 3221 } while (!*n); 3222 3223 # ifdef CONFIG_STACK_GROWSUP 3224 return (unsigned long)end_of_stack(p) - (unsigned long)n; 3225 # else 3226 return (unsigned long)n - (unsigned long)end_of_stack(p); 3227 # endif 3228 } 3229 #endif 3230 extern void set_task_stack_end_magic(struct task_struct *tsk); 3231 3232 /* set thread flags in other task's structures 3233 * - see asm/thread_info.h for TIF_xxxx flags available 3234 */ 3235 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 3236 { 3237 set_ti_thread_flag(task_thread_info(tsk), flag); 3238 } 3239 3240 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 3241 { 3242 clear_ti_thread_flag(task_thread_info(tsk), flag); 3243 } 3244 3245 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 3246 { 3247 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 3248 } 3249 3250 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 3251 { 3252 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 3253 } 3254 3255 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 3256 { 3257 return test_ti_thread_flag(task_thread_info(tsk), flag); 3258 } 3259 3260 static inline void set_tsk_need_resched(struct task_struct *tsk) 3261 { 3262 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 3263 } 3264 3265 static inline void clear_tsk_need_resched(struct task_struct *tsk) 3266 { 3267 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 3268 } 3269 3270 static inline int test_tsk_need_resched(struct task_struct *tsk) 3271 { 3272 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 3273 } 3274 3275 static inline int restart_syscall(void) 3276 { 3277 set_tsk_thread_flag(current, TIF_SIGPENDING); 3278 return -ERESTARTNOINTR; 3279 } 3280 3281 static inline int signal_pending(struct task_struct *p) 3282 { 3283 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); 3284 } 3285 3286 static inline int __fatal_signal_pending(struct task_struct *p) 3287 { 3288 return unlikely(sigismember(&p->pending.signal, SIGKILL)); 3289 } 3290 3291 static inline int fatal_signal_pending(struct task_struct *p) 3292 { 3293 return signal_pending(p) && __fatal_signal_pending(p); 3294 } 3295 3296 static inline int signal_pending_state(long state, struct task_struct *p) 3297 { 3298 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) 3299 return 0; 3300 if (!signal_pending(p)) 3301 return 0; 3302 3303 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); 3304 } 3305 3306 /* 3307 * cond_resched() and cond_resched_lock(): latency reduction via 3308 * explicit rescheduling in places that are safe. The return 3309 * value indicates whether a reschedule was done in fact. 3310 * cond_resched_lock() will drop the spinlock before scheduling, 3311 * cond_resched_softirq() will enable bhs before scheduling. 3312 */ 3313 #ifndef CONFIG_PREEMPT 3314 extern int _cond_resched(void); 3315 #else 3316 static inline int _cond_resched(void) { return 0; } 3317 #endif 3318 3319 #define cond_resched() ({ \ 3320 ___might_sleep(__FILE__, __LINE__, 0); \ 3321 _cond_resched(); \ 3322 }) 3323 3324 extern int __cond_resched_lock(spinlock_t *lock); 3325 3326 #define cond_resched_lock(lock) ({ \ 3327 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 3328 __cond_resched_lock(lock); \ 3329 }) 3330 3331 extern int __cond_resched_softirq(void); 3332 3333 #define cond_resched_softirq() ({ \ 3334 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ 3335 __cond_resched_softirq(); \ 3336 }) 3337 3338 static inline void cond_resched_rcu(void) 3339 { 3340 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 3341 rcu_read_unlock(); 3342 cond_resched(); 3343 rcu_read_lock(); 3344 #endif 3345 } 3346 3347 static inline unsigned long get_preempt_disable_ip(struct task_struct *p) 3348 { 3349 #ifdef CONFIG_DEBUG_PREEMPT 3350 return p->preempt_disable_ip; 3351 #else 3352 return 0; 3353 #endif 3354 } 3355 3356 /* 3357 * Does a critical section need to be broken due to another 3358 * task waiting?: (technically does not depend on CONFIG_PREEMPT, 3359 * but a general need for low latency) 3360 */ 3361 static inline int spin_needbreak(spinlock_t *lock) 3362 { 3363 #ifdef CONFIG_PREEMPT 3364 return spin_is_contended(lock); 3365 #else 3366 return 0; 3367 #endif 3368 } 3369 3370 /* 3371 * Idle thread specific functions to determine the need_resched 3372 * polling state. 3373 */ 3374 #ifdef TIF_POLLING_NRFLAG 3375 static inline int tsk_is_polling(struct task_struct *p) 3376 { 3377 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG); 3378 } 3379 3380 static inline void __current_set_polling(void) 3381 { 3382 set_thread_flag(TIF_POLLING_NRFLAG); 3383 } 3384 3385 static inline bool __must_check current_set_polling_and_test(void) 3386 { 3387 __current_set_polling(); 3388 3389 /* 3390 * Polling state must be visible before we test NEED_RESCHED, 3391 * paired by resched_curr() 3392 */ 3393 smp_mb__after_atomic(); 3394 3395 return unlikely(tif_need_resched()); 3396 } 3397 3398 static inline void __current_clr_polling(void) 3399 { 3400 clear_thread_flag(TIF_POLLING_NRFLAG); 3401 } 3402 3403 static inline bool __must_check current_clr_polling_and_test(void) 3404 { 3405 __current_clr_polling(); 3406 3407 /* 3408 * Polling state must be visible before we test NEED_RESCHED, 3409 * paired by resched_curr() 3410 */ 3411 smp_mb__after_atomic(); 3412 3413 return unlikely(tif_need_resched()); 3414 } 3415 3416 #else 3417 static inline int tsk_is_polling(struct task_struct *p) { return 0; } 3418 static inline void __current_set_polling(void) { } 3419 static inline void __current_clr_polling(void) { } 3420 3421 static inline bool __must_check current_set_polling_and_test(void) 3422 { 3423 return unlikely(tif_need_resched()); 3424 } 3425 static inline bool __must_check current_clr_polling_and_test(void) 3426 { 3427 return unlikely(tif_need_resched()); 3428 } 3429 #endif 3430 3431 static inline void current_clr_polling(void) 3432 { 3433 __current_clr_polling(); 3434 3435 /* 3436 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit. 3437 * Once the bit is cleared, we'll get IPIs with every new 3438 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also 3439 * fold. 3440 */ 3441 smp_mb(); /* paired with resched_curr() */ 3442 3443 preempt_fold_need_resched(); 3444 } 3445 3446 static __always_inline bool need_resched(void) 3447 { 3448 return unlikely(tif_need_resched()); 3449 } 3450 3451 /* 3452 * Thread group CPU time accounting. 3453 */ 3454 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 3455 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times); 3456 3457 /* 3458 * Reevaluate whether the task has signals pending delivery. 3459 * Wake the task if so. 3460 * This is required every time the blocked sigset_t changes. 3461 * callers must hold sighand->siglock. 3462 */ 3463 extern void recalc_sigpending_and_wake(struct task_struct *t); 3464 extern void recalc_sigpending(void); 3465 3466 extern void signal_wake_up_state(struct task_struct *t, unsigned int state); 3467 3468 static inline void signal_wake_up(struct task_struct *t, bool resume) 3469 { 3470 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); 3471 } 3472 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) 3473 { 3474 signal_wake_up_state(t, resume ? __TASK_TRACED : 0); 3475 } 3476 3477 /* 3478 * Wrappers for p->thread_info->cpu access. No-op on UP. 3479 */ 3480 #ifdef CONFIG_SMP 3481 3482 static inline unsigned int task_cpu(const struct task_struct *p) 3483 { 3484 #ifdef CONFIG_THREAD_INFO_IN_TASK 3485 return p->cpu; 3486 #else 3487 return task_thread_info(p)->cpu; 3488 #endif 3489 } 3490 3491 static inline int task_node(const struct task_struct *p) 3492 { 3493 return cpu_to_node(task_cpu(p)); 3494 } 3495 3496 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 3497 3498 #else 3499 3500 static inline unsigned int task_cpu(const struct task_struct *p) 3501 { 3502 return 0; 3503 } 3504 3505 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 3506 { 3507 } 3508 3509 #endif /* CONFIG_SMP */ 3510 3511 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 3512 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 3513 3514 #ifdef CONFIG_CGROUP_SCHED 3515 extern struct task_group root_task_group; 3516 #endif /* CONFIG_CGROUP_SCHED */ 3517 3518 extern int task_can_switch_user(struct user_struct *up, 3519 struct task_struct *tsk); 3520 3521 #ifdef CONFIG_TASK_XACCT 3522 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3523 { 3524 tsk->ioac.rchar += amt; 3525 } 3526 3527 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3528 { 3529 tsk->ioac.wchar += amt; 3530 } 3531 3532 static inline void inc_syscr(struct task_struct *tsk) 3533 { 3534 tsk->ioac.syscr++; 3535 } 3536 3537 static inline void inc_syscw(struct task_struct *tsk) 3538 { 3539 tsk->ioac.syscw++; 3540 } 3541 #else 3542 static inline void add_rchar(struct task_struct *tsk, ssize_t amt) 3543 { 3544 } 3545 3546 static inline void add_wchar(struct task_struct *tsk, ssize_t amt) 3547 { 3548 } 3549 3550 static inline void inc_syscr(struct task_struct *tsk) 3551 { 3552 } 3553 3554 static inline void inc_syscw(struct task_struct *tsk) 3555 { 3556 } 3557 #endif 3558 3559 #ifndef TASK_SIZE_OF 3560 #define TASK_SIZE_OF(tsk) TASK_SIZE 3561 #endif 3562 3563 #ifdef CONFIG_MEMCG 3564 extern void mm_update_next_owner(struct mm_struct *mm); 3565 #else 3566 static inline void mm_update_next_owner(struct mm_struct *mm) 3567 { 3568 } 3569 #endif /* CONFIG_MEMCG */ 3570 3571 static inline unsigned long task_rlimit(const struct task_struct *tsk, 3572 unsigned int limit) 3573 { 3574 return READ_ONCE(tsk->signal->rlim[limit].rlim_cur); 3575 } 3576 3577 static inline unsigned long task_rlimit_max(const struct task_struct *tsk, 3578 unsigned int limit) 3579 { 3580 return READ_ONCE(tsk->signal->rlim[limit].rlim_max); 3581 } 3582 3583 static inline unsigned long rlimit(unsigned int limit) 3584 { 3585 return task_rlimit(current, limit); 3586 } 3587 3588 static inline unsigned long rlimit_max(unsigned int limit) 3589 { 3590 return task_rlimit_max(current, limit); 3591 } 3592 3593 #define SCHED_CPUFREQ_RT (1U << 0) 3594 #define SCHED_CPUFREQ_DL (1U << 1) 3595 #define SCHED_CPUFREQ_IOWAIT (1U << 2) 3596 3597 #define SCHED_CPUFREQ_RT_DL (SCHED_CPUFREQ_RT | SCHED_CPUFREQ_DL) 3598 3599 #ifdef CONFIG_CPU_FREQ 3600 struct update_util_data { 3601 void (*func)(struct update_util_data *data, u64 time, unsigned int flags); 3602 }; 3603 3604 void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data, 3605 void (*func)(struct update_util_data *data, u64 time, 3606 unsigned int flags)); 3607 void cpufreq_remove_update_util_hook(int cpu); 3608 #endif /* CONFIG_CPU_FREQ */ 3609 3610 #endif 3611