1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SCHED_H
3 #define _LINUX_SCHED_H
4
5 /*
6 * Define 'struct task_struct' and provide the main scheduler
7 * APIs (schedule(), wakeup variants, etc.)
8 */
9
10 #include <uapi/linux/sched.h>
11
12 #include <asm/current.h>
13
14 #include <linux/pid.h>
15 #include <linux/sem.h>
16 #include <linux/shm.h>
17 #include <linux/kcov.h>
18 #include <linux/mutex.h>
19 #include <linux/plist.h>
20 #include <linux/hrtimer.h>
21 #include <linux/irqflags.h>
22 #include <linux/seccomp.h>
23 #include <linux/nodemask.h>
24 #include <linux/rcupdate.h>
25 #include <linux/refcount.h>
26 #include <linux/resource.h>
27 #include <linux/latencytop.h>
28 #include <linux/sched/prio.h>
29 #include <linux/sched/types.h>
30 #include <linux/signal_types.h>
31 #include <linux/mm_types_task.h>
32 #include <linux/task_io_accounting.h>
33 #include <linux/posix-timers.h>
34 #include <linux/rseq.h>
35 #include <linux/seqlock.h>
36 #include <linux/kcsan.h>
37 #include <linux/sched/rtg.h>
38
39 /* task_struct member predeclarations (sorted alphabetically): */
40 struct audit_context;
41 struct backing_dev_info;
42 struct bio_list;
43 struct blk_plug;
44 struct bpf_run_ctx;
45 struct capture_control;
46 struct cfs_rq;
47 struct fs_struct;
48 struct futex_pi_state;
49 struct io_context;
50 struct mempolicy;
51 struct nameidata;
52 struct nsproxy;
53 struct perf_event_context;
54 struct pid_namespace;
55 struct pipe_inode_info;
56 struct rcu_node;
57 struct reclaim_state;
58 struct robust_list_head;
59 struct root_domain;
60 struct rq;
61 struct sched_attr;
62 struct sched_param;
63 struct seq_file;
64 struct sighand_struct;
65 struct signal_struct;
66 struct task_delay_info;
67 struct task_group;
68 struct io_uring_task;
69
70 /*
71 * Task state bitmask. NOTE! These bits are also
72 * encoded in fs/proc/array.c: get_task_state().
73 *
74 * We have two separate sets of flags: task->state
75 * is about runnability, while task->exit_state are
76 * about the task exiting. Confusing, but this way
77 * modifying one set can't modify the other one by
78 * mistake.
79 */
80
81 /* Used in tsk->state: */
82 #define TASK_RUNNING 0x0000
83 #define TASK_INTERRUPTIBLE 0x0001
84 #define TASK_UNINTERRUPTIBLE 0x0002
85 #define __TASK_STOPPED 0x0004
86 #define __TASK_TRACED 0x0008
87 /* Used in tsk->exit_state: */
88 #define EXIT_DEAD 0x0010
89 #define EXIT_ZOMBIE 0x0020
90 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
91 /* Used in tsk->state again: */
92 #define TASK_PARKED 0x0040
93 #define TASK_DEAD 0x0080
94 #define TASK_WAKEKILL 0x0100
95 #define TASK_WAKING 0x0200
96 #define TASK_NOLOAD 0x0400
97 #define TASK_NEW 0x0800
98 #define TASK_STATE_MAX 0x1000
99
100 /* Convenience macros for the sake of set_current_state: */
101 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
102 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
103 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
104
105 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
106
107 /* Convenience macros for the sake of wake_up(): */
108 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
109
110 /* get_task_state(): */
111 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
112 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
113 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
114 TASK_PARKED)
115
116 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
117
118 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
119
120 #define task_is_stopped_or_traced(task) ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
121
122 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
123
124 /*
125 * Special states are those that do not use the normal wait-loop pattern. See
126 * the comment with set_special_state().
127 */
128 #define is_special_task_state(state) \
129 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
130
131 #define __set_current_state(state_value) \
132 do { \
133 WARN_ON_ONCE(is_special_task_state(state_value));\
134 current->task_state_change = _THIS_IP_; \
135 current->state = (state_value); \
136 } while (0)
137
138 #define set_current_state(state_value) \
139 do { \
140 WARN_ON_ONCE(is_special_task_state(state_value));\
141 current->task_state_change = _THIS_IP_; \
142 smp_store_mb(current->state, (state_value)); \
143 } while (0)
144
145 #define set_special_state(state_value) \
146 do { \
147 unsigned long flags; /* may shadow */ \
148 WARN_ON_ONCE(!is_special_task_state(state_value)); \
149 raw_spin_lock_irqsave(¤t->pi_lock, flags); \
150 current->task_state_change = _THIS_IP_; \
151 current->state = (state_value); \
152 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \
153 } while (0)
154 #else
155 /*
156 * set_current_state() includes a barrier so that the write of current->state
157 * is correctly serialised wrt the caller's subsequent test of whether to
158 * actually sleep:
159 *
160 * for (;;) {
161 * set_current_state(TASK_UNINTERRUPTIBLE);
162 * if (CONDITION)
163 * break;
164 *
165 * schedule();
166 * }
167 * __set_current_state(TASK_RUNNING);
168 *
169 * If the caller does not need such serialisation (because, for instance, the
170 * CONDITION test and condition change and wakeup are under the same lock) then
171 * use __set_current_state().
172 *
173 * The above is typically ordered against the wakeup, which does:
174 *
175 * CONDITION = 1;
176 * wake_up_state(p, TASK_UNINTERRUPTIBLE);
177 *
178 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before
179 * accessing p->state.
180 *
181 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
182 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
183 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
184 *
185 * However, with slightly different timing the wakeup TASK_RUNNING store can
186 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
187 * a problem either because that will result in one extra go around the loop
188 * and our @cond test will save the day.
189 *
190 * Also see the comments of try_to_wake_up().
191 */
192 #define __set_current_state(state_value) \
193 current->state = (state_value)
194
195 #define set_current_state(state_value) \
196 smp_store_mb(current->state, (state_value))
197
198 /*
199 * set_special_state() should be used for those states when the blocking task
200 * can not use the regular condition based wait-loop. In that case we must
201 * serialize against wakeups such that any possible in-flight TASK_RUNNING stores
202 * will not collide with our state change.
203 */
204 #define set_special_state(state_value) \
205 do { \
206 unsigned long flags; /* may shadow */ \
207 raw_spin_lock_irqsave(¤t->pi_lock, flags); \
208 current->state = (state_value); \
209 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \
210 } while (0)
211
212 #endif
213
214 /* Task command name length: */
215 #define TASK_COMM_LEN 16
216
217 enum task_event {
218 PUT_PREV_TASK = 0,
219 PICK_NEXT_TASK = 1,
220 TASK_WAKE = 2,
221 TASK_MIGRATE = 3,
222 TASK_UPDATE = 4,
223 IRQ_UPDATE = 5,
224 };
225
226 /* Note: this need to be in sync with migrate_type_names array */
227 enum migrate_types {
228 GROUP_TO_RQ,
229 RQ_TO_GROUP,
230 };
231
232 #ifdef CONFIG_CPU_ISOLATION_OPT
233 extern int sched_isolate_count(const cpumask_t *mask, bool include_offline);
234 extern int sched_isolate_cpu(int cpu);
235 extern int sched_unisolate_cpu(int cpu);
236 extern int sched_unisolate_cpu_unlocked(int cpu);
237 #else
sched_isolate_count(const cpumask_t * mask,bool include_offline)238 static inline int sched_isolate_count(const cpumask_t *mask,
239 bool include_offline)
240 {
241 cpumask_t count_mask;
242
243 if (include_offline)
244 cpumask_andnot(&count_mask, mask, cpu_online_mask);
245 else
246 return 0;
247
248 return cpumask_weight(&count_mask);
249 }
250
sched_isolate_cpu(int cpu)251 static inline int sched_isolate_cpu(int cpu)
252 {
253 return 0;
254 }
255
sched_unisolate_cpu(int cpu)256 static inline int sched_unisolate_cpu(int cpu)
257 {
258 return 0;
259 }
260
sched_unisolate_cpu_unlocked(int cpu)261 static inline int sched_unisolate_cpu_unlocked(int cpu)
262 {
263 return 0;
264 }
265 #endif
266
267 extern void scheduler_tick(void);
268
269 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
270
271 extern long schedule_timeout(long timeout);
272 extern long schedule_timeout_interruptible(long timeout);
273 extern long schedule_timeout_killable(long timeout);
274 extern long schedule_timeout_uninterruptible(long timeout);
275 extern long schedule_timeout_idle(long timeout);
276 asmlinkage void schedule(void);
277 extern void schedule_preempt_disabled(void);
278 asmlinkage void preempt_schedule_irq(void);
279
280 extern int __must_check io_schedule_prepare(void);
281 extern void io_schedule_finish(int token);
282 extern long io_schedule_timeout(long timeout);
283 extern void io_schedule(void);
284
285 /**
286 * struct prev_cputime - snapshot of system and user cputime
287 * @utime: time spent in user mode
288 * @stime: time spent in system mode
289 * @lock: protects the above two fields
290 *
291 * Stores previous user/system time values such that we can guarantee
292 * monotonicity.
293 */
294 struct prev_cputime {
295 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
296 u64 utime;
297 u64 stime;
298 raw_spinlock_t lock;
299 #endif
300 };
301
302 enum vtime_state {
303 /* Task is sleeping or running in a CPU with VTIME inactive: */
304 VTIME_INACTIVE = 0,
305 /* Task is idle */
306 VTIME_IDLE,
307 /* Task runs in kernelspace in a CPU with VTIME active: */
308 VTIME_SYS,
309 /* Task runs in userspace in a CPU with VTIME active: */
310 VTIME_USER,
311 /* Task runs as guests in a CPU with VTIME active: */
312 VTIME_GUEST,
313 };
314
315 struct vtime {
316 seqcount_t seqcount;
317 unsigned long long starttime;
318 enum vtime_state state;
319 unsigned int cpu;
320 u64 utime;
321 u64 stime;
322 u64 gtime;
323 };
324
325 /*
326 * Utilization clamp constraints.
327 * @UCLAMP_MIN: Minimum utilization
328 * @UCLAMP_MAX: Maximum utilization
329 * @UCLAMP_CNT: Utilization clamp constraints count
330 */
331 enum uclamp_id {
332 UCLAMP_MIN = 0,
333 UCLAMP_MAX,
334 UCLAMP_CNT
335 };
336
337 #ifdef CONFIG_SMP
338 extern struct root_domain def_root_domain;
339 extern struct mutex sched_domains_mutex;
340 #endif
341
342 struct sched_info {
343 #ifdef CONFIG_SCHED_INFO
344 /* Cumulative counters: */
345
346 /* # of times we have run on this CPU: */
347 unsigned long pcount;
348
349 /* Time spent waiting on a runqueue: */
350 unsigned long long run_delay;
351
352 /* Timestamps: */
353
354 /* When did we last run on a CPU? */
355 unsigned long long last_arrival;
356
357 /* When were we last queued to run? */
358 unsigned long long last_queued;
359
360 #endif /* CONFIG_SCHED_INFO */
361 };
362
363 /*
364 * Integer metrics need fixed point arithmetic, e.g., sched/fair
365 * has a few: load, load_avg, util_avg, freq, and capacity.
366 *
367 * We define a basic fixed point arithmetic range, and then formalize
368 * all these metrics based on that basic range.
369 */
370 # define SCHED_FIXEDPOINT_SHIFT 10
371 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
372
373 /* Increase resolution of cpu_capacity calculations */
374 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
375 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
376
377 struct load_weight {
378 unsigned long weight;
379 u32 inv_weight;
380 };
381
382 /**
383 * struct util_est - Estimation utilization of FAIR tasks
384 * @enqueued: instantaneous estimated utilization of a task/cpu
385 * @ewma: the Exponential Weighted Moving Average (EWMA)
386 * utilization of a task
387 *
388 * Support data structure to track an Exponential Weighted Moving Average
389 * (EWMA) of a FAIR task's utilization. New samples are added to the moving
390 * average each time a task completes an activation. Sample's weight is chosen
391 * so that the EWMA will be relatively insensitive to transient changes to the
392 * task's workload.
393 *
394 * The enqueued attribute has a slightly different meaning for tasks and cpus:
395 * - task: the task's util_avg at last task dequeue time
396 * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
397 * Thus, the util_est.enqueued of a task represents the contribution on the
398 * estimated utilization of the CPU where that task is currently enqueued.
399 *
400 * Only for tasks we track a moving average of the past instantaneous
401 * estimated utilization. This allows to absorb sporadic drops in utilization
402 * of an otherwise almost periodic task.
403 *
404 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
405 * updates. When a task is dequeued, its util_est should not be updated if its
406 * util_avg has not been updated in the meantime.
407 * This information is mapped into the MSB bit of util_est.enqueued at dequeue
408 * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg
409 * for a task) it is safe to use MSB.
410 */
411 struct util_est {
412 unsigned int enqueued;
413 unsigned int ewma;
414 #define UTIL_EST_WEIGHT_SHIFT 2
415 #define UTIL_AVG_UNCHANGED 0x80000000
416 } __attribute__((__aligned__(sizeof(u64))));
417
418 /*
419 * The load/runnable/util_avg accumulates an infinite geometric series
420 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
421 *
422 * [load_avg definition]
423 *
424 * load_avg = runnable% * scale_load_down(load)
425 *
426 * [runnable_avg definition]
427 *
428 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE
429 *
430 * [util_avg definition]
431 *
432 * util_avg = running% * SCHED_CAPACITY_SCALE
433 *
434 * where runnable% is the time ratio that a sched_entity is runnable and
435 * running% the time ratio that a sched_entity is running.
436 *
437 * For cfs_rq, they are the aggregated values of all runnable and blocked
438 * sched_entities.
439 *
440 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
441 * capacity scaling. The scaling is done through the rq_clock_pelt that is used
442 * for computing those signals (see update_rq_clock_pelt())
443 *
444 * N.B., the above ratios (runnable% and running%) themselves are in the
445 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
446 * to as large a range as necessary. This is for example reflected by
447 * util_avg's SCHED_CAPACITY_SCALE.
448 *
449 * [Overflow issue]
450 *
451 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
452 * with the highest load (=88761), always runnable on a single cfs_rq,
453 * and should not overflow as the number already hits PID_MAX_LIMIT.
454 *
455 * For all other cases (including 32-bit kernels), struct load_weight's
456 * weight will overflow first before we do, because:
457 *
458 * Max(load_avg) <= Max(load.weight)
459 *
460 * Then it is the load_weight's responsibility to consider overflow
461 * issues.
462 */
463 struct sched_avg {
464 u64 last_update_time;
465 u64 load_sum;
466 u64 runnable_sum;
467 u32 util_sum;
468 u32 period_contrib;
469 unsigned long load_avg;
470 unsigned long runnable_avg;
471 unsigned long util_avg;
472 struct util_est util_est;
473 } ____cacheline_aligned;
474
475 struct sched_statistics {
476 #ifdef CONFIG_SCHEDSTATS
477 u64 wait_start;
478 u64 wait_max;
479 u64 wait_count;
480 u64 wait_sum;
481 u64 iowait_count;
482 u64 iowait_sum;
483
484 u64 sleep_start;
485 u64 sleep_max;
486 s64 sum_sleep_runtime;
487
488 u64 block_start;
489 u64 block_max;
490 u64 exec_max;
491 u64 slice_max;
492
493 u64 nr_migrations_cold;
494 u64 nr_failed_migrations_affine;
495 u64 nr_failed_migrations_running;
496 u64 nr_failed_migrations_hot;
497 u64 nr_forced_migrations;
498
499 u64 nr_wakeups;
500 u64 nr_wakeups_sync;
501 u64 nr_wakeups_migrate;
502 u64 nr_wakeups_local;
503 u64 nr_wakeups_remote;
504 u64 nr_wakeups_affine;
505 u64 nr_wakeups_affine_attempts;
506 u64 nr_wakeups_passive;
507 u64 nr_wakeups_idle;
508 #endif
509 };
510
511 struct sched_entity {
512 /* For load-balancing: */
513 struct load_weight load;
514 struct rb_node run_node;
515 struct list_head group_node;
516 unsigned int on_rq;
517
518 u64 exec_start;
519 u64 sum_exec_runtime;
520 u64 vruntime;
521 u64 prev_sum_exec_runtime;
522
523 u64 nr_migrations;
524
525 struct sched_statistics statistics;
526
527 #ifdef CONFIG_FAIR_GROUP_SCHED
528 int depth;
529 struct sched_entity *parent;
530 /* rq on which this entity is (to be) queued: */
531 struct cfs_rq *cfs_rq;
532 /* rq "owned" by this entity/group: */
533 struct cfs_rq *my_q;
534 /* cached value of my_q->h_nr_running */
535 unsigned long runnable_weight;
536 #endif
537
538 #ifdef CONFIG_SMP
539 /*
540 * Per entity load average tracking.
541 *
542 * Put into separate cache line so it does not
543 * collide with read-mostly values above.
544 */
545 struct sched_avg avg;
546 #endif
547 };
548
549 #ifdef CONFIG_SCHED_WALT
550 extern void sched_exit(struct task_struct *p);
551 extern int sched_set_init_task_load(struct task_struct *p, int init_load_pct);
552 extern u32 sched_get_init_task_load(struct task_struct *p);
553 extern void free_task_load_ptrs(struct task_struct *p);
554 #define RAVG_HIST_SIZE_MAX 5
555 struct ravg {
556 /*
557 * 'mark_start' marks the beginning of an event (task waking up, task
558 * starting to execute, task being preempted) within a window
559 *
560 * 'sum' represents how runnable a task has been within current
561 * window. It incorporates both running time and wait time and is
562 * frequency scaled.
563 *
564 * 'sum_history' keeps track of history of 'sum' seen over previous
565 * RAVG_HIST_SIZE windows. Windows where task was entirely sleeping are
566 * ignored.
567 *
568 * 'demand' represents maximum sum seen over previous
569 * sysctl_sched_ravg_hist_size windows. 'demand' could drive frequency
570 * demand for tasks.
571 *
572 * 'curr_window_cpu' represents task's contribution to cpu busy time on
573 * various CPUs in the current window
574 *
575 * 'prev_window_cpu' represents task's contribution to cpu busy time on
576 * various CPUs in the previous window
577 *
578 * 'curr_window' represents the sum of all entries in curr_window_cpu
579 *
580 * 'prev_window' represents the sum of all entries in prev_window_cpu
581 *
582 */
583 u64 mark_start;
584 u32 sum, demand;
585 u32 sum_history[RAVG_HIST_SIZE_MAX];
586 u32 *curr_window_cpu, *prev_window_cpu;
587 u32 curr_window, prev_window;
588 u16 active_windows;
589 u16 demand_scaled;
590 };
591 #else
sched_exit(struct task_struct * p)592 static inline void sched_exit(struct task_struct *p) { }
free_task_load_ptrs(struct task_struct * p)593 static inline void free_task_load_ptrs(struct task_struct *p) { }
594 #endif /* CONFIG_SCHED_WALT */
595
596 struct sched_rt_entity {
597 struct list_head run_list;
598 unsigned long timeout;
599 unsigned long watchdog_stamp;
600 unsigned int time_slice;
601 unsigned short on_rq;
602 unsigned short on_list;
603
604 struct sched_rt_entity *back;
605 #ifdef CONFIG_RT_GROUP_SCHED
606 struct sched_rt_entity *parent;
607 /* rq on which this entity is (to be) queued: */
608 struct rt_rq *rt_rq;
609 /* rq "owned" by this entity/group: */
610 struct rt_rq *my_q;
611 #endif
612 } __randomize_layout;
613
614 struct sched_dl_entity {
615 struct rb_node rb_node;
616
617 /*
618 * Original scheduling parameters. Copied here from sched_attr
619 * during sched_setattr(), they will remain the same until
620 * the next sched_setattr().
621 */
622 u64 dl_runtime; /* Maximum runtime for each instance */
623 u64 dl_deadline; /* Relative deadline of each instance */
624 u64 dl_period; /* Separation of two instances (period) */
625 u64 dl_bw; /* dl_runtime / dl_period */
626 u64 dl_density; /* dl_runtime / dl_deadline */
627
628 /*
629 * Actual scheduling parameters. Initialized with the values above,
630 * they are continuously updated during task execution. Note that
631 * the remaining runtime could be < 0 in case we are in overrun.
632 */
633 s64 runtime; /* Remaining runtime for this instance */
634 u64 deadline; /* Absolute deadline for this instance */
635 unsigned int flags; /* Specifying the scheduler behaviour */
636
637 /*
638 * Some bool flags:
639 *
640 * @dl_throttled tells if we exhausted the runtime. If so, the
641 * task has to wait for a replenishment to be performed at the
642 * next firing of dl_timer.
643 *
644 * @dl_boosted tells if we are boosted due to DI. If so we are
645 * outside bandwidth enforcement mechanism (but only until we
646 * exit the critical section);
647 *
648 * @dl_yielded tells if task gave up the CPU before consuming
649 * all its available runtime during the last job.
650 *
651 * @dl_non_contending tells if the task is inactive while still
652 * contributing to the active utilization. In other words, it
653 * indicates if the inactive timer has been armed and its handler
654 * has not been executed yet. This flag is useful to avoid race
655 * conditions between the inactive timer handler and the wakeup
656 * code.
657 *
658 * @dl_overrun tells if the task asked to be informed about runtime
659 * overruns.
660 */
661 unsigned int dl_throttled : 1;
662 unsigned int dl_yielded : 1;
663 unsigned int dl_non_contending : 1;
664 unsigned int dl_overrun : 1;
665
666 /*
667 * Bandwidth enforcement timer. Each -deadline task has its
668 * own bandwidth to be enforced, thus we need one timer per task.
669 */
670 struct hrtimer dl_timer;
671
672 /*
673 * Inactive timer, responsible for decreasing the active utilization
674 * at the "0-lag time". When a -deadline task blocks, it contributes
675 * to GRUB's active utilization until the "0-lag time", hence a
676 * timer is needed to decrease the active utilization at the correct
677 * time.
678 */
679 struct hrtimer inactive_timer;
680
681 #ifdef CONFIG_RT_MUTEXES
682 /*
683 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
684 * pi_se points to the donor, otherwise points to the dl_se it belongs
685 * to (the original one/itself).
686 */
687 struct sched_dl_entity *pi_se;
688 #endif
689 };
690
691 #ifdef CONFIG_UCLAMP_TASK
692 /* Number of utilization clamp buckets (shorter alias) */
693 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
694
695 /*
696 * Utilization clamp for a scheduling entity
697 * @value: clamp value "assigned" to a se
698 * @bucket_id: bucket index corresponding to the "assigned" value
699 * @active: the se is currently refcounted in a rq's bucket
700 * @user_defined: the requested clamp value comes from user-space
701 *
702 * The bucket_id is the index of the clamp bucket matching the clamp value
703 * which is pre-computed and stored to avoid expensive integer divisions from
704 * the fast path.
705 *
706 * The active bit is set whenever a task has got an "effective" value assigned,
707 * which can be different from the clamp value "requested" from user-space.
708 * This allows to know a task is refcounted in the rq's bucket corresponding
709 * to the "effective" bucket_id.
710 *
711 * The user_defined bit is set whenever a task has got a task-specific clamp
712 * value requested from userspace, i.e. the system defaults apply to this task
713 * just as a restriction. This allows to relax default clamps when a less
714 * restrictive task-specific value has been requested, thus allowing to
715 * implement a "nice" semantic. For example, a task running with a 20%
716 * default boost can still drop its own boosting to 0%.
717 */
718 struct uclamp_se {
719 unsigned int value : bits_per(SCHED_CAPACITY_SCALE);
720 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS);
721 unsigned int active : 1;
722 unsigned int user_defined : 1;
723 };
724 #endif /* CONFIG_UCLAMP_TASK */
725
726 union rcu_special {
727 struct {
728 u8 blocked;
729 u8 need_qs;
730 u8 exp_hint; /* Hint for performance. */
731 u8 need_mb; /* Readers need smp_mb(). */
732 } b; /* Bits. */
733 u32 s; /* Set of bits. */
734 };
735
736 enum perf_event_task_context {
737 perf_invalid_context = -1,
738 perf_hw_context = 0,
739 perf_sw_context,
740 perf_nr_task_contexts,
741 };
742
743 struct wake_q_node {
744 struct wake_q_node *next;
745 };
746
747 struct task_struct {
748 #ifdef CONFIG_THREAD_INFO_IN_TASK
749 /*
750 * For reasons of header soup (see current_thread_info()), this
751 * must be the first element of task_struct.
752 */
753 struct thread_info thread_info;
754 #endif
755 /* -1 unrunnable, 0 runnable, >0 stopped: */
756 volatile long state;
757
758 /*
759 * This begins the randomizable portion of task_struct. Only
760 * scheduling-critical items should be added above here.
761 */
762 randomized_struct_fields_start
763
764 void *stack;
765 refcount_t usage;
766 /* Per task flags (PF_*), defined further below: */
767 unsigned int flags;
768 unsigned int ptrace;
769
770 #ifdef CONFIG_SMP
771 int on_cpu;
772 struct __call_single_node wake_entry;
773 #ifdef CONFIG_THREAD_INFO_IN_TASK
774 /* Current CPU: */
775 unsigned int cpu;
776 #endif
777 unsigned int wakee_flips;
778 unsigned long wakee_flip_decay_ts;
779 struct task_struct *last_wakee;
780
781 /*
782 * recent_used_cpu is initially set as the last CPU used by a task
783 * that wakes affine another task. Waker/wakee relationships can
784 * push tasks around a CPU where each wakeup moves to the next one.
785 * Tracking a recently used CPU allows a quick search for a recently
786 * used CPU that may be idle.
787 */
788 int recent_used_cpu;
789 int wake_cpu;
790 #endif
791 int on_rq;
792
793 int prio;
794 int static_prio;
795 int normal_prio;
796 unsigned int rt_priority;
797
798 const struct sched_class *sched_class;
799 struct sched_entity se;
800 struct sched_rt_entity rt;
801 #ifdef CONFIG_SCHED_WALT
802 struct ravg ravg;
803 /*
804 * 'init_load_pct' represents the initial task load assigned to children
805 * of this task
806 */
807 u32 init_load_pct;
808 u64 last_sleep_ts;
809 #endif
810
811 #ifdef CONFIG_SCHED_RTG
812 int rtg_depth;
813 struct related_thread_group *grp;
814 struct list_head grp_list;
815 #endif
816
817 #ifdef CONFIG_CGROUP_SCHED
818 struct task_group *sched_task_group;
819 #endif
820 struct sched_dl_entity dl;
821
822 #ifdef CONFIG_UCLAMP_TASK
823 /*
824 * Clamp values requested for a scheduling entity.
825 * Must be updated with task_rq_lock() held.
826 */
827 struct uclamp_se uclamp_req[UCLAMP_CNT];
828 /*
829 * Effective clamp values used for a scheduling entity.
830 * Must be updated with task_rq_lock() held.
831 */
832 struct uclamp_se uclamp[UCLAMP_CNT];
833 #endif
834
835 #ifdef CONFIG_PREEMPT_NOTIFIERS
836 /* List of struct preempt_notifier: */
837 struct hlist_head preempt_notifiers;
838 #endif
839
840 #ifdef CONFIG_BLK_DEV_IO_TRACE
841 unsigned int btrace_seq;
842 #endif
843
844 unsigned int policy;
845 int nr_cpus_allowed;
846 const cpumask_t *cpus_ptr;
847 cpumask_t cpus_mask;
848
849 #ifdef CONFIG_PREEMPT_RCU
850 int rcu_read_lock_nesting;
851 union rcu_special rcu_read_unlock_special;
852 struct list_head rcu_node_entry;
853 struct rcu_node *rcu_blocked_node;
854 #endif /* #ifdef CONFIG_PREEMPT_RCU */
855
856 #ifdef CONFIG_TASKS_RCU
857 unsigned long rcu_tasks_nvcsw;
858 u8 rcu_tasks_holdout;
859 u8 rcu_tasks_idx;
860 int rcu_tasks_idle_cpu;
861 struct list_head rcu_tasks_holdout_list;
862 #endif /* #ifdef CONFIG_TASKS_RCU */
863
864 #ifdef CONFIG_TASKS_TRACE_RCU
865 int trc_reader_nesting;
866 int trc_ipi_to_cpu;
867 union rcu_special trc_reader_special;
868 bool trc_reader_checked;
869 struct list_head trc_holdout_list;
870 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
871
872 struct sched_info sched_info;
873
874 struct list_head tasks;
875 #ifdef CONFIG_SMP
876 struct plist_node pushable_tasks;
877 struct rb_node pushable_dl_tasks;
878 #endif
879
880 struct mm_struct *mm;
881 struct mm_struct *active_mm;
882
883 /* Per-thread vma caching: */
884 struct vmacache vmacache;
885
886 #ifdef SPLIT_RSS_COUNTING
887 struct task_rss_stat rss_stat;
888 #endif
889 int exit_state;
890 int exit_code;
891 int exit_signal;
892 /* The signal sent when the parent dies: */
893 int pdeath_signal;
894 /* JOBCTL_*, siglock protected: */
895 unsigned long jobctl;
896
897 /* Used for emulating ABI behavior of previous Linux versions: */
898 unsigned int personality;
899
900 /* Scheduler bits, serialized by scheduler locks: */
901 unsigned sched_reset_on_fork:1;
902 unsigned sched_contributes_to_load:1;
903 unsigned sched_migrated:1;
904 #ifdef CONFIG_PSI
905 unsigned sched_psi_wake_requeue:1;
906 #endif
907
908 /* Force alignment to the next boundary: */
909 unsigned :0;
910
911 /* Unserialized, strictly 'current' */
912
913 /*
914 * This field must not be in the scheduler word above due to wakelist
915 * queueing no longer being serialized by p->on_cpu. However:
916 *
917 * p->XXX = X; ttwu()
918 * schedule() if (p->on_rq && ..) // false
919 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true
920 * deactivate_task() ttwu_queue_wakelist())
921 * p->on_rq = 0; p->sched_remote_wakeup = Y;
922 *
923 * guarantees all stores of 'current' are visible before
924 * ->sched_remote_wakeup gets used, so it can be in this word.
925 */
926 unsigned sched_remote_wakeup:1;
927
928 /* Bit to tell LSMs we're in execve(): */
929 unsigned in_execve:1;
930 unsigned in_iowait:1;
931 #ifndef TIF_RESTORE_SIGMASK
932 unsigned restore_sigmask:1;
933 #endif
934 #ifdef CONFIG_MEMCG
935 unsigned in_user_fault:1;
936 #endif
937 #ifdef CONFIG_COMPAT_BRK
938 unsigned brk_randomized:1;
939 #endif
940 #ifdef CONFIG_CGROUPS
941 /* disallow userland-initiated cgroup migration */
942 unsigned no_cgroup_migration:1;
943 /* task is frozen/stopped (used by the cgroup freezer) */
944 unsigned frozen:1;
945 #endif
946 #ifdef CONFIG_BLK_CGROUP
947 unsigned use_memdelay:1;
948 #endif
949 #ifdef CONFIG_PSI
950 /* Stalled due to lack of memory */
951 unsigned in_memstall:1;
952 #endif
953
954 unsigned long atomic_flags; /* Flags requiring atomic access. */
955
956 struct restart_block restart_block;
957
958 pid_t pid;
959 pid_t tgid;
960
961 #ifdef CONFIG_STACKPROTECTOR
962 /* Canary value for the -fstack-protector GCC feature: */
963 unsigned long stack_canary;
964 #endif
965 /*
966 * Pointers to the (original) parent process, youngest child, younger sibling,
967 * older sibling, respectively. (p->father can be replaced with
968 * p->real_parent->pid)
969 */
970
971 /* Real parent process: */
972 struct task_struct __rcu *real_parent;
973
974 /* Recipient of SIGCHLD, wait4() reports: */
975 struct task_struct __rcu *parent;
976
977 /*
978 * Children/sibling form the list of natural children:
979 */
980 struct list_head children;
981 struct list_head sibling;
982 struct task_struct *group_leader;
983
984 /*
985 * 'ptraced' is the list of tasks this task is using ptrace() on.
986 *
987 * This includes both natural children and PTRACE_ATTACH targets.
988 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
989 */
990 struct list_head ptraced;
991 struct list_head ptrace_entry;
992
993 /* PID/PID hash table linkage. */
994 struct pid *thread_pid;
995 struct hlist_node pid_links[PIDTYPE_MAX];
996 struct list_head thread_group;
997 struct list_head thread_node;
998
999 struct completion *vfork_done;
1000
1001 /* CLONE_CHILD_SETTID: */
1002 int __user *set_child_tid;
1003
1004 /* CLONE_CHILD_CLEARTID: */
1005 int __user *clear_child_tid;
1006
1007 u64 utime;
1008 u64 stime;
1009 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1010 u64 utimescaled;
1011 u64 stimescaled;
1012 #endif
1013 u64 gtime;
1014 struct prev_cputime prev_cputime;
1015 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1016 struct vtime vtime;
1017 #endif
1018
1019 #ifdef CONFIG_NO_HZ_FULL
1020 atomic_t tick_dep_mask;
1021 #endif
1022 /* Context switch counts: */
1023 unsigned long nvcsw;
1024 unsigned long nivcsw;
1025
1026 /* Monotonic time in nsecs: */
1027 u64 start_time;
1028
1029 /* Boot based time in nsecs: */
1030 u64 start_boottime;
1031
1032 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1033 unsigned long min_flt;
1034 unsigned long maj_flt;
1035
1036 /* Empty if CONFIG_POSIX_CPUTIMERS=n */
1037 struct posix_cputimers posix_cputimers;
1038
1039 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1040 struct posix_cputimers_work posix_cputimers_work;
1041 #endif
1042
1043 /* Process credentials: */
1044
1045 /* Tracer's credentials at attach: */
1046 const struct cred __rcu *ptracer_cred;
1047
1048 /* Objective and real subjective task credentials (COW): */
1049 const struct cred __rcu *real_cred;
1050
1051 /* Effective (overridable) subjective task credentials (COW): */
1052 const struct cred __rcu *cred;
1053
1054 #ifdef CONFIG_KEYS
1055 /* Cached requested key. */
1056 struct key *cached_requested_key;
1057 #endif
1058
1059 /*
1060 * executable name, excluding path.
1061 *
1062 * - normally initialized setup_new_exec()
1063 * - access it with [gs]et_task_comm()
1064 * - lock it with task_lock()
1065 */
1066 char comm[TASK_COMM_LEN];
1067
1068 struct nameidata *nameidata;
1069
1070 #ifdef CONFIG_SYSVIPC
1071 struct sysv_sem sysvsem;
1072 struct sysv_shm sysvshm;
1073 #endif
1074 #ifdef CONFIG_DETECT_HUNG_TASK
1075 unsigned long last_switch_count;
1076 unsigned long last_switch_time;
1077 #endif
1078 /* Filesystem information: */
1079 struct fs_struct *fs;
1080
1081 /* Open file information: */
1082 struct files_struct *files;
1083
1084 #ifdef CONFIG_IO_URING
1085 struct io_uring_task *io_uring;
1086 #endif
1087
1088 /* Namespaces: */
1089 struct nsproxy *nsproxy;
1090
1091 /* Signal handlers: */
1092 struct signal_struct *signal;
1093 struct sighand_struct __rcu *sighand;
1094 sigset_t blocked;
1095 sigset_t real_blocked;
1096 /* Restored if set_restore_sigmask() was used: */
1097 sigset_t saved_sigmask;
1098 struct sigpending pending;
1099 unsigned long sas_ss_sp;
1100 size_t sas_ss_size;
1101 unsigned int sas_ss_flags;
1102
1103 struct callback_head *task_works;
1104
1105 #ifdef CONFIG_AUDIT
1106 #ifdef CONFIG_AUDITSYSCALL
1107 struct audit_context *audit_context;
1108 #endif
1109 kuid_t loginuid;
1110 unsigned int sessionid;
1111 #endif
1112 struct seccomp seccomp;
1113
1114 /* Thread group tracking: */
1115 u64 parent_exec_id;
1116 u64 self_exec_id;
1117
1118 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1119 spinlock_t alloc_lock;
1120
1121 /* Protection of the PI data structures: */
1122 raw_spinlock_t pi_lock;
1123
1124 struct wake_q_node wake_q;
1125
1126 #ifdef CONFIG_RT_MUTEXES
1127 /* PI waiters blocked on a rt_mutex held by this task: */
1128 struct rb_root_cached pi_waiters;
1129 /* Updated under owner's pi_lock and rq lock */
1130 struct task_struct *pi_top_task;
1131 /* Deadlock detection and priority inheritance handling: */
1132 struct rt_mutex_waiter *pi_blocked_on;
1133 #endif
1134
1135 #ifdef CONFIG_DEBUG_MUTEXES
1136 /* Mutex deadlock detection: */
1137 struct mutex_waiter *blocked_on;
1138 #endif
1139
1140 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1141 int non_block_count;
1142 #endif
1143
1144 #ifdef CONFIG_TRACE_IRQFLAGS
1145 struct irqtrace_events irqtrace;
1146 unsigned int hardirq_threaded;
1147 u64 hardirq_chain_key;
1148 int softirqs_enabled;
1149 int softirq_context;
1150 int irq_config;
1151 #endif
1152
1153 #ifdef CONFIG_LOCKDEP
1154 # define MAX_LOCK_DEPTH 48UL
1155 u64 curr_chain_key;
1156 int lockdep_depth;
1157 unsigned int lockdep_recursion;
1158 struct held_lock held_locks[MAX_LOCK_DEPTH];
1159 #endif
1160
1161 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1162 unsigned int in_ubsan;
1163 #endif
1164
1165 /* Journalling filesystem info: */
1166 void *journal_info;
1167
1168 /* Stacked block device info: */
1169 struct bio_list *bio_list;
1170
1171 #ifdef CONFIG_BLOCK
1172 /* Stack plugging: */
1173 struct blk_plug *plug;
1174 #endif
1175
1176 /* VM state: */
1177 struct reclaim_state *reclaim_state;
1178
1179 struct backing_dev_info *backing_dev_info;
1180
1181 struct io_context *io_context;
1182
1183 #ifdef CONFIG_COMPACTION
1184 struct capture_control *capture_control;
1185 #endif
1186 /* Ptrace state: */
1187 unsigned long ptrace_message;
1188 kernel_siginfo_t *last_siginfo;
1189
1190 struct task_io_accounting ioac;
1191 #ifdef CONFIG_PSI
1192 /* Pressure stall state */
1193 unsigned int psi_flags;
1194 #endif
1195 #ifdef CONFIG_TASK_XACCT
1196 /* Accumulated RSS usage: */
1197 u64 acct_rss_mem1;
1198 /* Accumulated virtual memory usage: */
1199 u64 acct_vm_mem1;
1200 /* stime + utime since last update: */
1201 u64 acct_timexpd;
1202 #endif
1203 #ifdef CONFIG_CPUSETS
1204 /* Protected by ->alloc_lock: */
1205 nodemask_t mems_allowed;
1206 /* Seqence number to catch updates: */
1207 seqcount_spinlock_t mems_allowed_seq;
1208 int cpuset_mem_spread_rotor;
1209 int cpuset_slab_spread_rotor;
1210 #endif
1211 #ifdef CONFIG_CGROUPS
1212 /* Control Group info protected by css_set_lock: */
1213 struct css_set __rcu *cgroups;
1214 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
1215 struct list_head cg_list;
1216 #endif
1217 #ifdef CONFIG_X86_CPU_RESCTRL
1218 u32 closid;
1219 u32 rmid;
1220 #endif
1221 #ifdef CONFIG_FUTEX
1222 struct robust_list_head __user *robust_list;
1223 #ifdef CONFIG_COMPAT
1224 struct compat_robust_list_head __user *compat_robust_list;
1225 #endif
1226 struct list_head pi_state_list;
1227 struct futex_pi_state *pi_state_cache;
1228 struct mutex futex_exit_mutex;
1229 unsigned int futex_state;
1230 #endif
1231 #ifdef CONFIG_PERF_EVENTS
1232 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1233 struct mutex perf_event_mutex;
1234 struct list_head perf_event_list;
1235 #endif
1236 #ifdef CONFIG_DEBUG_PREEMPT
1237 unsigned long preempt_disable_ip;
1238 #endif
1239 #ifdef CONFIG_NUMA
1240 /* Protected by alloc_lock: */
1241 struct mempolicy *mempolicy;
1242 short il_prev;
1243 short pref_node_fork;
1244 #endif
1245 #ifdef CONFIG_NUMA_BALANCING
1246 int numa_scan_seq;
1247 unsigned int numa_scan_period;
1248 unsigned int numa_scan_period_max;
1249 int numa_preferred_nid;
1250 unsigned long numa_migrate_retry;
1251 /* Migration stamp: */
1252 u64 node_stamp;
1253 u64 last_task_numa_placement;
1254 u64 last_sum_exec_runtime;
1255 struct callback_head numa_work;
1256
1257 /*
1258 * This pointer is only modified for current in syscall and
1259 * pagefault context (and for tasks being destroyed), so it can be read
1260 * from any of the following contexts:
1261 * - RCU read-side critical section
1262 * - current->numa_group from everywhere
1263 * - task's runqueue locked, task not running
1264 */
1265 struct numa_group __rcu *numa_group;
1266
1267 /*
1268 * numa_faults is an array split into four regions:
1269 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1270 * in this precise order.
1271 *
1272 * faults_memory: Exponential decaying average of faults on a per-node
1273 * basis. Scheduling placement decisions are made based on these
1274 * counts. The values remain static for the duration of a PTE scan.
1275 * faults_cpu: Track the nodes the process was running on when a NUMA
1276 * hinting fault was incurred.
1277 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1278 * during the current scan window. When the scan completes, the counts
1279 * in faults_memory and faults_cpu decay and these values are copied.
1280 */
1281 unsigned long *numa_faults;
1282 unsigned long total_numa_faults;
1283
1284 /*
1285 * numa_faults_locality tracks if faults recorded during the last
1286 * scan window were remote/local or failed to migrate. The task scan
1287 * period is adapted based on the locality of the faults with different
1288 * weights depending on whether they were shared or private faults
1289 */
1290 unsigned long numa_faults_locality[3];
1291
1292 unsigned long numa_pages_migrated;
1293 #endif /* CONFIG_NUMA_BALANCING */
1294
1295 #ifdef CONFIG_RSEQ
1296 struct rseq __user *rseq;
1297 u32 rseq_sig;
1298 /*
1299 * RmW on rseq_event_mask must be performed atomically
1300 * with respect to preemption.
1301 */
1302 unsigned long rseq_event_mask;
1303 #endif
1304
1305 struct tlbflush_unmap_batch tlb_ubc;
1306
1307 union {
1308 refcount_t rcu_users;
1309 struct rcu_head rcu;
1310 };
1311
1312 /* Cache last used pipe for splice(): */
1313 struct pipe_inode_info *splice_pipe;
1314
1315 struct page_frag task_frag;
1316
1317 #ifdef CONFIG_TASK_DELAY_ACCT
1318 struct task_delay_info *delays;
1319 #endif
1320
1321 #ifdef CONFIG_FAULT_INJECTION
1322 int make_it_fail;
1323 unsigned int fail_nth;
1324 #endif
1325 /*
1326 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1327 * balance_dirty_pages() for a dirty throttling pause:
1328 */
1329 int nr_dirtied;
1330 int nr_dirtied_pause;
1331 /* Start of a write-and-pause period: */
1332 unsigned long dirty_paused_when;
1333
1334 #ifdef CONFIG_LATENCYTOP
1335 int latency_record_count;
1336 struct latency_record latency_record[LT_SAVECOUNT];
1337 #endif
1338 /*
1339 * Time slack values; these are used to round up poll() and
1340 * select() etc timeout values. These are in nanoseconds.
1341 */
1342 u64 timer_slack_ns;
1343 u64 default_timer_slack_ns;
1344
1345 #ifdef CONFIG_KASAN
1346 unsigned int kasan_depth;
1347 #endif
1348
1349 #ifdef CONFIG_KCSAN
1350 struct kcsan_ctx kcsan_ctx;
1351 #ifdef CONFIG_TRACE_IRQFLAGS
1352 struct irqtrace_events kcsan_save_irqtrace;
1353 #endif
1354 #endif
1355
1356 #if IS_ENABLED(CONFIG_KUNIT)
1357 struct kunit *kunit_test;
1358 #endif
1359
1360 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1361 /* Index of current stored address in ret_stack: */
1362 int curr_ret_stack;
1363 int curr_ret_depth;
1364
1365 /* Stack of return addresses for return function tracing: */
1366 struct ftrace_ret_stack *ret_stack;
1367
1368 /* Timestamp for last schedule: */
1369 unsigned long long ftrace_timestamp;
1370
1371 /*
1372 * Number of functions that haven't been traced
1373 * because of depth overrun:
1374 */
1375 atomic_t trace_overrun;
1376
1377 /* Pause tracing: */
1378 atomic_t tracing_graph_pause;
1379 #endif
1380
1381 #ifdef CONFIG_TRACING
1382 /* State flags for use by tracers: */
1383 unsigned long trace;
1384
1385 /* Bitmask and counter of trace recursion: */
1386 unsigned long trace_recursion;
1387 #endif /* CONFIG_TRACING */
1388
1389 #ifdef CONFIG_KCOV
1390 /* See kernel/kcov.c for more details. */
1391
1392 /* Coverage collection mode enabled for this task (0 if disabled): */
1393 unsigned int kcov_mode;
1394
1395 /* Size of the kcov_area: */
1396 unsigned int kcov_size;
1397
1398 /* Buffer for coverage collection: */
1399 void *kcov_area;
1400
1401 /* KCOV descriptor wired with this task or NULL: */
1402 struct kcov *kcov;
1403
1404 /* KCOV common handle for remote coverage collection: */
1405 u64 kcov_handle;
1406
1407 /* KCOV sequence number: */
1408 int kcov_sequence;
1409
1410 /* Collect coverage from softirq context: */
1411 unsigned int kcov_softirq;
1412 #endif
1413
1414 #ifdef CONFIG_MEMCG
1415 struct mem_cgroup *memcg_in_oom;
1416 gfp_t memcg_oom_gfp_mask;
1417 int memcg_oom_order;
1418
1419 /* Number of pages to reclaim on returning to userland: */
1420 unsigned int memcg_nr_pages_over_high;
1421
1422 /* Used by memcontrol for targeted memcg charge: */
1423 struct mem_cgroup *active_memcg;
1424 #endif
1425
1426 #ifdef CONFIG_BLK_CGROUP
1427 struct request_queue *throttle_queue;
1428 #endif
1429
1430 #ifdef CONFIG_UPROBES
1431 struct uprobe_task *utask;
1432 #endif
1433 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1434 unsigned int sequential_io;
1435 unsigned int sequential_io_avg;
1436 #endif
1437 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1438 unsigned long task_state_change;
1439 #endif
1440 int pagefault_disabled;
1441 #ifdef CONFIG_MMU
1442 struct task_struct *oom_reaper_list;
1443 #endif
1444 #ifdef CONFIG_VMAP_STACK
1445 struct vm_struct *stack_vm_area;
1446 #endif
1447 #ifdef CONFIG_THREAD_INFO_IN_TASK
1448 /* A live task holds one reference: */
1449 refcount_t stack_refcount;
1450 #endif
1451 #ifdef CONFIG_LIVEPATCH
1452 int patch_state;
1453 #endif
1454 #ifdef CONFIG_SECURITY
1455 /* Used by LSM modules for access restriction: */
1456 void *security;
1457 #endif
1458 #ifdef CONFIG_BPF_SYSCALL
1459 /* Used for BPF run context */
1460 struct bpf_run_ctx *bpf_ctx;
1461 #endif
1462
1463 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1464 unsigned long lowest_stack;
1465 unsigned long prev_lowest_stack;
1466 #endif
1467
1468 #ifdef CONFIG_X86_MCE
1469 void __user *mce_vaddr;
1470 __u64 mce_kflags;
1471 u64 mce_addr;
1472 __u64 mce_ripv : 1,
1473 mce_whole_page : 1,
1474 __mce_reserved : 62;
1475 struct callback_head mce_kill_me;
1476 int mce_count;
1477 #endif
1478
1479 #ifdef CONFIG_ACCESS_TOKENID
1480 u64 token;
1481 u64 ftoken;
1482 #endif
1483 /*
1484 * New fields for task_struct should be added above here, so that
1485 * they are included in the randomized portion of task_struct.
1486 */
1487 randomized_struct_fields_end
1488
1489 /* CPU-specific state of this task: */
1490 struct thread_struct thread;
1491
1492 /*
1493 * WARNING: on x86, 'thread_struct' contains a variable-sized
1494 * structure. It *MUST* be at the end of 'task_struct'.
1495 *
1496 * Do not put anything below here!
1497 */
1498 };
1499
task_pid(struct task_struct * task)1500 static inline struct pid *task_pid(struct task_struct *task)
1501 {
1502 return task->thread_pid;
1503 }
1504
1505 /*
1506 * the helpers to get the task's different pids as they are seen
1507 * from various namespaces
1508 *
1509 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1510 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1511 * current.
1512 * task_xid_nr_ns() : id seen from the ns specified;
1513 *
1514 * see also pid_nr() etc in include/linux/pid.h
1515 */
1516 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1517
task_pid_nr(struct task_struct * tsk)1518 static inline pid_t task_pid_nr(struct task_struct *tsk)
1519 {
1520 return tsk->pid;
1521 }
1522
task_pid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1523 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1524 {
1525 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1526 }
1527
task_pid_vnr(struct task_struct * tsk)1528 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1529 {
1530 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1531 }
1532
1533
task_tgid_nr(struct task_struct * tsk)1534 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1535 {
1536 return tsk->tgid;
1537 }
1538
1539 /**
1540 * pid_alive - check that a task structure is not stale
1541 * @p: Task structure to be checked.
1542 *
1543 * Test if a process is not yet dead (at most zombie state)
1544 * If pid_alive fails, then pointers within the task structure
1545 * can be stale and must not be dereferenced.
1546 *
1547 * Return: 1 if the process is alive. 0 otherwise.
1548 */
pid_alive(const struct task_struct * p)1549 static inline int pid_alive(const struct task_struct *p)
1550 {
1551 return p->thread_pid != NULL;
1552 }
1553
task_pgrp_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1554 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1555 {
1556 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1557 }
1558
task_pgrp_vnr(struct task_struct * tsk)1559 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1560 {
1561 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1562 }
1563
1564
task_session_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1565 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1566 {
1567 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1568 }
1569
task_session_vnr(struct task_struct * tsk)1570 static inline pid_t task_session_vnr(struct task_struct *tsk)
1571 {
1572 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1573 }
1574
task_tgid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1575 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1576 {
1577 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1578 }
1579
task_tgid_vnr(struct task_struct * tsk)1580 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1581 {
1582 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1583 }
1584
task_ppid_nr_ns(const struct task_struct * tsk,struct pid_namespace * ns)1585 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1586 {
1587 pid_t pid = 0;
1588
1589 rcu_read_lock();
1590 if (pid_alive(tsk))
1591 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1592 rcu_read_unlock();
1593
1594 return pid;
1595 }
1596
task_ppid_nr(const struct task_struct * tsk)1597 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1598 {
1599 return task_ppid_nr_ns(tsk, &init_pid_ns);
1600 }
1601
1602 /* Obsolete, do not use: */
task_pgrp_nr(struct task_struct * tsk)1603 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1604 {
1605 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1606 }
1607
1608 #define TASK_REPORT_IDLE (TASK_REPORT + 1)
1609 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1610
task_state_index(struct task_struct * tsk)1611 static inline unsigned int task_state_index(struct task_struct *tsk)
1612 {
1613 unsigned int tsk_state = READ_ONCE(tsk->state);
1614 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1615
1616 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1617
1618 if (tsk_state == TASK_IDLE)
1619 state = TASK_REPORT_IDLE;
1620
1621 return fls(state);
1622 }
1623
task_index_to_char(unsigned int state)1624 static inline char task_index_to_char(unsigned int state)
1625 {
1626 static const char state_char[] = "RSDTtXZPI";
1627
1628 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1629
1630 return state_char[state];
1631 }
1632
task_state_to_char(struct task_struct * tsk)1633 static inline char task_state_to_char(struct task_struct *tsk)
1634 {
1635 return task_index_to_char(task_state_index(tsk));
1636 }
1637
1638 /**
1639 * is_global_init - check if a task structure is init. Since init
1640 * is free to have sub-threads we need to check tgid.
1641 * @tsk: Task structure to be checked.
1642 *
1643 * Check if a task structure is the first user space task the kernel created.
1644 *
1645 * Return: 1 if the task structure is init. 0 otherwise.
1646 */
is_global_init(struct task_struct * tsk)1647 static inline int is_global_init(struct task_struct *tsk)
1648 {
1649 return task_tgid_nr(tsk) == 1;
1650 }
1651
1652 extern struct pid *cad_pid;
1653
1654 /*
1655 * Per process flags
1656 */
1657 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */
1658 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1659 #define PF_EXITING 0x00000004 /* Getting shut down */
1660 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */
1661 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1662 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1663 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1664 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1665 #define PF_DUMPCORE 0x00000200 /* Dumped core */
1666 #define PF_SIGNALED 0x00000400 /* Killed by a signal */
1667 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
1668 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1669 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1670 #define PF_USED_ASYNC 0x00004000 /* Used async_schedule*(), used by module init */
1671 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1672 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */
1673 #define PF_KSWAPD 0x00020000 /* I am kswapd */
1674 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */
1675 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */
1676 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to,
1677 * I am cleaning dirty pages from some other bdi. */
1678 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1679 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1680 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1681 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
1682 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1683 #define PF_MEMALLOC_NOCMA 0x10000000 /* All allocation request will have _GFP_MOVABLE cleared */
1684 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1685 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1686
1687 /*
1688 * Only the _current_ task can read/write to tsk->flags, but other
1689 * tasks can access tsk->flags in readonly mode for example
1690 * with tsk_used_math (like during threaded core dumping).
1691 * There is however an exception to this rule during ptrace
1692 * or during fork: the ptracer task is allowed to write to the
1693 * child->flags of its traced child (same goes for fork, the parent
1694 * can write to the child->flags), because we're guaranteed the
1695 * child is not running and in turn not changing child->flags
1696 * at the same time the parent does it.
1697 */
1698 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1699 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1700 #define clear_used_math() clear_stopped_child_used_math(current)
1701 #define set_used_math() set_stopped_child_used_math(current)
1702
1703 #define conditional_stopped_child_used_math(condition, child) \
1704 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1705
1706 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1707
1708 #define copy_to_stopped_child_used_math(child) \
1709 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1710
1711 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1712 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1713 #define used_math() tsk_used_math(current)
1714
is_percpu_thread(void)1715 static __always_inline bool is_percpu_thread(void)
1716 {
1717 #ifdef CONFIG_SMP
1718 return (current->flags & PF_NO_SETAFFINITY) &&
1719 (current->nr_cpus_allowed == 1);
1720 #else
1721 return true;
1722 #endif
1723 }
1724
1725 /* Per-process atomic flags. */
1726 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1727 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1728 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1729 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */
1730 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/
1731 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */
1732 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */
1733 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */
1734
1735 #define TASK_PFA_TEST(name, func) \
1736 static inline bool task_##func(struct task_struct *p) \
1737 { return test_bit(PFA_##name, &p->atomic_flags); }
1738
1739 #define TASK_PFA_SET(name, func) \
1740 static inline void task_set_##func(struct task_struct *p) \
1741 { set_bit(PFA_##name, &p->atomic_flags); }
1742
1743 #define TASK_PFA_CLEAR(name, func) \
1744 static inline void task_clear_##func(struct task_struct *p) \
1745 { clear_bit(PFA_##name, &p->atomic_flags); }
1746
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1747 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1748 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1749
1750 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1751 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1752 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1753
1754 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1755 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1756 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1757
1758 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1759 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1760 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1761
1762 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1763 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1764 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1765
1766 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1767 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1768
1769 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1770 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1771 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1772
1773 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1774 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1775
1776 static inline void
1777 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1778 {
1779 current->flags &= ~flags;
1780 current->flags |= orig_flags & flags;
1781 }
1782
1783 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1784 extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
1785 #ifdef CONFIG_SMP
1786 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1787 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1788 #else
do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1789 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1790 {
1791 }
set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1792 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1793 {
1794 if (!cpumask_test_cpu(0, new_mask))
1795 return -EINVAL;
1796 return 0;
1797 }
1798 #endif
1799
1800 extern int yield_to(struct task_struct *p, bool preempt);
1801 extern void set_user_nice(struct task_struct *p, long nice);
1802 extern int task_prio(const struct task_struct *p);
1803
1804 /**
1805 * task_nice - return the nice value of a given task.
1806 * @p: the task in question.
1807 *
1808 * Return: The nice value [ -20 ... 0 ... 19 ].
1809 */
task_nice(const struct task_struct * p)1810 static inline int task_nice(const struct task_struct *p)
1811 {
1812 return PRIO_TO_NICE((p)->static_prio);
1813 }
1814
1815 extern int can_nice(const struct task_struct *p, const int nice);
1816 extern int task_curr(const struct task_struct *p);
1817 extern int idle_cpu(int cpu);
1818 extern int available_idle_cpu(int cpu);
1819 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1820 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1821 extern void sched_set_fifo(struct task_struct *p);
1822 extern void sched_set_fifo_low(struct task_struct *p);
1823 extern void sched_set_normal(struct task_struct *p, int nice);
1824 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1825 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1826 extern struct task_struct *idle_task(int cpu);
1827
1828 /**
1829 * is_idle_task - is the specified task an idle task?
1830 * @p: the task in question.
1831 *
1832 * Return: 1 if @p is an idle task. 0 otherwise.
1833 */
is_idle_task(const struct task_struct * p)1834 static __always_inline bool is_idle_task(const struct task_struct *p)
1835 {
1836 return !!(p->flags & PF_IDLE);
1837 }
1838
1839 extern struct task_struct *curr_task(int cpu);
1840 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1841
1842 void yield(void);
1843
1844 union thread_union {
1845 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1846 struct task_struct task;
1847 #endif
1848 #ifndef CONFIG_THREAD_INFO_IN_TASK
1849 struct thread_info thread_info;
1850 #endif
1851 unsigned long stack[THREAD_SIZE/sizeof(long)];
1852 };
1853
1854 #ifndef CONFIG_THREAD_INFO_IN_TASK
1855 extern struct thread_info init_thread_info;
1856 #endif
1857
1858 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1859
1860 #ifdef CONFIG_THREAD_INFO_IN_TASK
task_thread_info(struct task_struct * task)1861 static inline struct thread_info *task_thread_info(struct task_struct *task)
1862 {
1863 return &task->thread_info;
1864 }
1865 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1866 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1867 #endif
1868
1869 /*
1870 * find a task by one of its numerical ids
1871 *
1872 * find_task_by_pid_ns():
1873 * finds a task by its pid in the specified namespace
1874 * find_task_by_vpid():
1875 * finds a task by its virtual pid
1876 *
1877 * see also find_vpid() etc in include/linux/pid.h
1878 */
1879
1880 extern struct task_struct *find_task_by_vpid(pid_t nr);
1881 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1882
1883 /*
1884 * find a task by its virtual pid and get the task struct
1885 */
1886 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1887
1888 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1889 extern int wake_up_process(struct task_struct *tsk);
1890 extern void wake_up_new_task(struct task_struct *tsk);
1891
1892 #ifdef CONFIG_SMP
1893 extern void kick_process(struct task_struct *tsk);
1894 #else
kick_process(struct task_struct * tsk)1895 static inline void kick_process(struct task_struct *tsk) { }
1896 #endif
1897
1898 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1899
set_task_comm(struct task_struct * tsk,const char * from)1900 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1901 {
1902 __set_task_comm(tsk, from, false);
1903 }
1904
1905 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1906 #define get_task_comm(buf, tsk) ({ \
1907 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \
1908 __get_task_comm(buf, sizeof(buf), tsk); \
1909 })
1910
1911 #ifdef CONFIG_SMP
scheduler_ipi(void)1912 static __always_inline void scheduler_ipi(void)
1913 {
1914 /*
1915 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1916 * TIF_NEED_RESCHED remotely (for the first time) will also send
1917 * this IPI.
1918 */
1919 preempt_fold_need_resched();
1920 }
1921 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
1922 #else
scheduler_ipi(void)1923 static inline void scheduler_ipi(void) { }
wait_task_inactive(struct task_struct * p,long match_state)1924 static inline unsigned long wait_task_inactive(struct task_struct *p, long match_state)
1925 {
1926 return 1;
1927 }
1928 #endif
1929
1930 /*
1931 * Set thread flags in other task's structures.
1932 * See asm/thread_info.h for TIF_xxxx flags available:
1933 */
set_tsk_thread_flag(struct task_struct * tsk,int flag)1934 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1935 {
1936 set_ti_thread_flag(task_thread_info(tsk), flag);
1937 }
1938
clear_tsk_thread_flag(struct task_struct * tsk,int flag)1939 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1940 {
1941 clear_ti_thread_flag(task_thread_info(tsk), flag);
1942 }
1943
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)1944 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
1945 bool value)
1946 {
1947 update_ti_thread_flag(task_thread_info(tsk), flag, value);
1948 }
1949
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)1950 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1951 {
1952 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1953 }
1954
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)1955 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1956 {
1957 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1958 }
1959
test_tsk_thread_flag(struct task_struct * tsk,int flag)1960 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1961 {
1962 return test_ti_thread_flag(task_thread_info(tsk), flag);
1963 }
1964
set_tsk_need_resched(struct task_struct * tsk)1965 static inline void set_tsk_need_resched(struct task_struct *tsk)
1966 {
1967 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1968 }
1969
clear_tsk_need_resched(struct task_struct * tsk)1970 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1971 {
1972 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1973 }
1974
test_tsk_need_resched(struct task_struct * tsk)1975 static inline int test_tsk_need_resched(struct task_struct *tsk)
1976 {
1977 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1978 }
1979
1980 /*
1981 * cond_resched() and cond_resched_lock(): latency reduction via
1982 * explicit rescheduling in places that are safe. The return
1983 * value indicates whether a reschedule was done in fact.
1984 * cond_resched_lock() will drop the spinlock before scheduling,
1985 */
1986 #ifndef CONFIG_PREEMPTION
1987 extern int _cond_resched(void);
1988 #else
_cond_resched(void)1989 static inline int _cond_resched(void) { return 0; }
1990 #endif
1991
1992 #define cond_resched() ({ \
1993 ___might_sleep(__FILE__, __LINE__, 0); \
1994 _cond_resched(); \
1995 })
1996
1997 extern int __cond_resched_lock(spinlock_t *lock);
1998
1999 #define cond_resched_lock(lock) ({ \
2000 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2001 __cond_resched_lock(lock); \
2002 })
2003
cond_resched_rcu(void)2004 static inline void cond_resched_rcu(void)
2005 {
2006 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2007 rcu_read_unlock();
2008 cond_resched();
2009 rcu_read_lock();
2010 #endif
2011 }
2012
2013 /*
2014 * Does a critical section need to be broken due to another
2015 * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
2016 * but a general need for low latency)
2017 */
spin_needbreak(spinlock_t * lock)2018 static inline int spin_needbreak(spinlock_t *lock)
2019 {
2020 #ifdef CONFIG_PREEMPTION
2021 return spin_is_contended(lock);
2022 #else
2023 return 0;
2024 #endif
2025 }
2026
need_resched(void)2027 static __always_inline bool need_resched(void)
2028 {
2029 return unlikely(tif_need_resched());
2030 }
2031
2032 /*
2033 * Wrappers for p->thread_info->cpu access. No-op on UP.
2034 */
2035 #ifdef CONFIG_SMP
2036
task_cpu(const struct task_struct * p)2037 static inline unsigned int task_cpu(const struct task_struct *p)
2038 {
2039 #ifdef CONFIG_THREAD_INFO_IN_TASK
2040 return READ_ONCE(p->cpu);
2041 #else
2042 return READ_ONCE(task_thread_info(p)->cpu);
2043 #endif
2044 }
2045
2046 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2047
2048 #else
2049
task_cpu(const struct task_struct * p)2050 static inline unsigned int task_cpu(const struct task_struct *p)
2051 {
2052 return 0;
2053 }
2054
set_task_cpu(struct task_struct * p,unsigned int cpu)2055 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2056 {
2057 }
2058
2059 #endif /* CONFIG_SMP */
2060
2061 /*
2062 * In order to reduce various lock holder preemption latencies provide an
2063 * interface to see if a vCPU is currently running or not.
2064 *
2065 * This allows us to terminate optimistic spin loops and block, analogous to
2066 * the native optimistic spin heuristic of testing if the lock owner task is
2067 * running or not.
2068 */
2069 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2070 static inline bool vcpu_is_preempted(int cpu)
2071 {
2072 return false;
2073 }
2074 #endif
2075
2076 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2077 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2078
2079 #ifndef TASK_SIZE_OF
2080 #define TASK_SIZE_OF(tsk) TASK_SIZE
2081 #endif
2082
2083 #ifdef CONFIG_RSEQ
2084
2085 /*
2086 * Map the event mask on the user-space ABI enum rseq_cs_flags
2087 * for direct mask checks.
2088 */
2089 enum rseq_event_mask_bits {
2090 RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
2091 RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
2092 RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
2093 };
2094
2095 enum rseq_event_mask {
2096 RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT),
2097 RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT),
2098 RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT),
2099 };
2100
rseq_set_notify_resume(struct task_struct * t)2101 static inline void rseq_set_notify_resume(struct task_struct *t)
2102 {
2103 if (t->rseq)
2104 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
2105 }
2106
2107 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
2108
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2109 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2110 struct pt_regs *regs)
2111 {
2112 if (current->rseq)
2113 __rseq_handle_notify_resume(ksig, regs);
2114 }
2115
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2116 static inline void rseq_signal_deliver(struct ksignal *ksig,
2117 struct pt_regs *regs)
2118 {
2119 preempt_disable();
2120 __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask);
2121 preempt_enable();
2122 rseq_handle_notify_resume(ksig, regs);
2123 }
2124
2125 /* rseq_preempt() requires preemption to be disabled. */
rseq_preempt(struct task_struct * t)2126 static inline void rseq_preempt(struct task_struct *t)
2127 {
2128 __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
2129 rseq_set_notify_resume(t);
2130 }
2131
2132 /* rseq_migrate() requires preemption to be disabled. */
rseq_migrate(struct task_struct * t)2133 static inline void rseq_migrate(struct task_struct *t)
2134 {
2135 __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
2136 rseq_set_notify_resume(t);
2137 }
2138
2139 /*
2140 * If parent process has a registered restartable sequences area, the
2141 * child inherits. Unregister rseq for a clone with CLONE_VM set.
2142 */
rseq_fork(struct task_struct * t,unsigned long clone_flags)2143 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2144 {
2145 if (clone_flags & CLONE_VM) {
2146 t->rseq = NULL;
2147 t->rseq_sig = 0;
2148 t->rseq_event_mask = 0;
2149 } else {
2150 t->rseq = current->rseq;
2151 t->rseq_sig = current->rseq_sig;
2152 t->rseq_event_mask = current->rseq_event_mask;
2153 }
2154 }
2155
rseq_execve(struct task_struct * t)2156 static inline void rseq_execve(struct task_struct *t)
2157 {
2158 t->rseq = NULL;
2159 t->rseq_sig = 0;
2160 t->rseq_event_mask = 0;
2161 }
2162
2163 #else
2164
rseq_set_notify_resume(struct task_struct * t)2165 static inline void rseq_set_notify_resume(struct task_struct *t)
2166 {
2167 }
rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2168 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
2169 struct pt_regs *regs)
2170 {
2171 }
rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2172 static inline void rseq_signal_deliver(struct ksignal *ksig,
2173 struct pt_regs *regs)
2174 {
2175 }
rseq_preempt(struct task_struct * t)2176 static inline void rseq_preempt(struct task_struct *t)
2177 {
2178 }
rseq_migrate(struct task_struct * t)2179 static inline void rseq_migrate(struct task_struct *t)
2180 {
2181 }
rseq_fork(struct task_struct * t,unsigned long clone_flags)2182 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
2183 {
2184 }
rseq_execve(struct task_struct * t)2185 static inline void rseq_execve(struct task_struct *t)
2186 {
2187 }
2188
2189 #endif
2190
2191 #ifdef CONFIG_DEBUG_RSEQ
2192
2193 void rseq_syscall(struct pt_regs *regs);
2194
2195 #else
2196
rseq_syscall(struct pt_regs * regs)2197 static inline void rseq_syscall(struct pt_regs *regs)
2198 {
2199 }
2200
2201 #endif
2202
2203 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq);
2204 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len);
2205 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq);
2206
2207 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq);
2208 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
2209 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
2210
2211 int sched_trace_rq_cpu(struct rq *rq);
2212 int sched_trace_rq_cpu_capacity(struct rq *rq);
2213 int sched_trace_rq_nr_running(struct rq *rq);
2214
2215 const struct cpumask *sched_trace_rd_span(struct root_domain *rd);
2216
2217 #endif
2218