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/kmsan_types.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/syscall_user_dispatch.h> |
32 | #include <linux/mm_types_task.h> |
33 | #include <linux/task_io_accounting.h> |
34 | #include <linux/posix-timers.h> |
35 | #include <linux/rseq.h> |
36 | #include <linux/seqlock.h> |
37 | #include <linux/kcsan.h> |
38 | #include <linux/rv.h> |
39 | #include <linux/livepatch_sched.h> |
40 | #include <asm/kmap_size.h> |
41 | |
42 | /* task_struct member predeclarations (sorted alphabetically): */ |
43 | struct audit_context; |
44 | struct bio_list; |
45 | struct blk_plug; |
46 | struct bpf_local_storage; |
47 | struct bpf_run_ctx; |
48 | struct capture_control; |
49 | struct cfs_rq; |
50 | struct fs_struct; |
51 | struct futex_pi_state; |
52 | struct io_context; |
53 | struct io_uring_task; |
54 | struct mempolicy; |
55 | struct nameidata; |
56 | struct nsproxy; |
57 | struct perf_event_context; |
58 | struct pid_namespace; |
59 | struct pipe_inode_info; |
60 | struct rcu_node; |
61 | struct reclaim_state; |
62 | struct robust_list_head; |
63 | struct root_domain; |
64 | struct rq; |
65 | struct sched_attr; |
66 | struct seq_file; |
67 | struct sighand_struct; |
68 | struct signal_struct; |
69 | struct task_delay_info; |
70 | struct task_group; |
71 | struct user_event_mm; |
72 | |
73 | /* |
74 | * Task state bitmask. NOTE! These bits are also |
75 | * encoded in fs/proc/array.c: get_task_state(). |
76 | * |
77 | * We have two separate sets of flags: task->__state |
78 | * is about runnability, while task->exit_state are |
79 | * about the task exiting. Confusing, but this way |
80 | * modifying one set can't modify the other one by |
81 | * mistake. |
82 | */ |
83 | |
84 | /* Used in tsk->__state: */ |
85 | #define TASK_RUNNING 0x00000000 |
86 | #define TASK_INTERRUPTIBLE 0x00000001 |
87 | #define TASK_UNINTERRUPTIBLE 0x00000002 |
88 | #define __TASK_STOPPED 0x00000004 |
89 | #define __TASK_TRACED 0x00000008 |
90 | /* Used in tsk->exit_state: */ |
91 | #define EXIT_DEAD 0x00000010 |
92 | #define EXIT_ZOMBIE 0x00000020 |
93 | #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) |
94 | /* Used in tsk->__state again: */ |
95 | #define TASK_PARKED 0x00000040 |
96 | #define TASK_DEAD 0x00000080 |
97 | #define TASK_WAKEKILL 0x00000100 |
98 | #define TASK_WAKING 0x00000200 |
99 | #define TASK_NOLOAD 0x00000400 |
100 | #define TASK_NEW 0x00000800 |
101 | #define TASK_RTLOCK_WAIT 0x00001000 |
102 | #define TASK_FREEZABLE 0x00002000 |
103 | #define __TASK_FREEZABLE_UNSAFE (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP)) |
104 | #define TASK_FROZEN 0x00008000 |
105 | #define TASK_STATE_MAX 0x00010000 |
106 | |
107 | #define TASK_ANY (TASK_STATE_MAX-1) |
108 | |
109 | /* |
110 | * DO NOT ADD ANY NEW USERS ! |
111 | */ |
112 | #define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE) |
113 | |
114 | /* Convenience macros for the sake of set_current_state: */ |
115 | #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) |
116 | #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) |
117 | #define TASK_TRACED __TASK_TRACED |
118 | |
119 | #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) |
120 | |
121 | /* Convenience macros for the sake of wake_up(): */ |
122 | #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) |
123 | |
124 | /* get_task_state(): */ |
125 | #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ |
126 | TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ |
127 | __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ |
128 | TASK_PARKED) |
129 | |
130 | #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) |
131 | |
132 | #define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0) |
133 | #define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0) |
134 | #define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0) |
135 | |
136 | /* |
137 | * Special states are those that do not use the normal wait-loop pattern. See |
138 | * the comment with set_special_state(). |
139 | */ |
140 | #define is_special_task_state(state) \ |
141 | ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD)) |
142 | |
143 | #ifdef CONFIG_DEBUG_ATOMIC_SLEEP |
144 | # define debug_normal_state_change(state_value) \ |
145 | do { \ |
146 | WARN_ON_ONCE(is_special_task_state(state_value)); \ |
147 | current->task_state_change = _THIS_IP_; \ |
148 | } while (0) |
149 | |
150 | # define debug_special_state_change(state_value) \ |
151 | do { \ |
152 | WARN_ON_ONCE(!is_special_task_state(state_value)); \ |
153 | current->task_state_change = _THIS_IP_; \ |
154 | } while (0) |
155 | |
156 | # define debug_rtlock_wait_set_state() \ |
157 | do { \ |
158 | current->saved_state_change = current->task_state_change;\ |
159 | current->task_state_change = _THIS_IP_; \ |
160 | } while (0) |
161 | |
162 | # define debug_rtlock_wait_restore_state() \ |
163 | do { \ |
164 | current->task_state_change = current->saved_state_change;\ |
165 | } while (0) |
166 | |
167 | #else |
168 | # define debug_normal_state_change(cond) do { } while (0) |
169 | # define debug_special_state_change(cond) do { } while (0) |
170 | # define debug_rtlock_wait_set_state() do { } while (0) |
171 | # define debug_rtlock_wait_restore_state() do { } while (0) |
172 | #endif |
173 | |
174 | /* |
175 | * set_current_state() includes a barrier so that the write of current->__state |
176 | * is correctly serialised wrt the caller's subsequent test of whether to |
177 | * actually sleep: |
178 | * |
179 | * for (;;) { |
180 | * set_current_state(TASK_UNINTERRUPTIBLE); |
181 | * if (CONDITION) |
182 | * break; |
183 | * |
184 | * schedule(); |
185 | * } |
186 | * __set_current_state(TASK_RUNNING); |
187 | * |
188 | * If the caller does not need such serialisation (because, for instance, the |
189 | * CONDITION test and condition change and wakeup are under the same lock) then |
190 | * use __set_current_state(). |
191 | * |
192 | * The above is typically ordered against the wakeup, which does: |
193 | * |
194 | * CONDITION = 1; |
195 | * wake_up_state(p, TASK_UNINTERRUPTIBLE); |
196 | * |
197 | * where wake_up_state()/try_to_wake_up() executes a full memory barrier before |
198 | * accessing p->__state. |
199 | * |
200 | * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is, |
201 | * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a |
202 | * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). |
203 | * |
204 | * However, with slightly different timing the wakeup TASK_RUNNING store can |
205 | * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not |
206 | * a problem either because that will result in one extra go around the loop |
207 | * and our @cond test will save the day. |
208 | * |
209 | * Also see the comments of try_to_wake_up(). |
210 | */ |
211 | #define __set_current_state(state_value) \ |
212 | do { \ |
213 | debug_normal_state_change((state_value)); \ |
214 | WRITE_ONCE(current->__state, (state_value)); \ |
215 | } while (0) |
216 | |
217 | #define set_current_state(state_value) \ |
218 | do { \ |
219 | debug_normal_state_change((state_value)); \ |
220 | smp_store_mb(current->__state, (state_value)); \ |
221 | } while (0) |
222 | |
223 | /* |
224 | * set_special_state() should be used for those states when the blocking task |
225 | * can not use the regular condition based wait-loop. In that case we must |
226 | * serialize against wakeups such that any possible in-flight TASK_RUNNING |
227 | * stores will not collide with our state change. |
228 | */ |
229 | #define set_special_state(state_value) \ |
230 | do { \ |
231 | unsigned long flags; /* may shadow */ \ |
232 | \ |
233 | raw_spin_lock_irqsave(¤t->pi_lock, flags); \ |
234 | debug_special_state_change((state_value)); \ |
235 | WRITE_ONCE(current->__state, (state_value)); \ |
236 | raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ |
237 | } while (0) |
238 | |
239 | /* |
240 | * PREEMPT_RT specific variants for "sleeping" spin/rwlocks |
241 | * |
242 | * RT's spin/rwlock substitutions are state preserving. The state of the |
243 | * task when blocking on the lock is saved in task_struct::saved_state and |
244 | * restored after the lock has been acquired. These operations are |
245 | * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT |
246 | * lock related wakeups while the task is blocked on the lock are |
247 | * redirected to operate on task_struct::saved_state to ensure that these |
248 | * are not dropped. On restore task_struct::saved_state is set to |
249 | * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail. |
250 | * |
251 | * The lock operation looks like this: |
252 | * |
253 | * current_save_and_set_rtlock_wait_state(); |
254 | * for (;;) { |
255 | * if (try_lock()) |
256 | * break; |
257 | * raw_spin_unlock_irq(&lock->wait_lock); |
258 | * schedule_rtlock(); |
259 | * raw_spin_lock_irq(&lock->wait_lock); |
260 | * set_current_state(TASK_RTLOCK_WAIT); |
261 | * } |
262 | * current_restore_rtlock_saved_state(); |
263 | */ |
264 | #define current_save_and_set_rtlock_wait_state() \ |
265 | do { \ |
266 | lockdep_assert_irqs_disabled(); \ |
267 | raw_spin_lock(¤t->pi_lock); \ |
268 | current->saved_state = current->__state; \ |
269 | debug_rtlock_wait_set_state(); \ |
270 | WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ |
271 | raw_spin_unlock(¤t->pi_lock); \ |
272 | } while (0); |
273 | |
274 | #define current_restore_rtlock_saved_state() \ |
275 | do { \ |
276 | lockdep_assert_irqs_disabled(); \ |
277 | raw_spin_lock(¤t->pi_lock); \ |
278 | debug_rtlock_wait_restore_state(); \ |
279 | WRITE_ONCE(current->__state, current->saved_state); \ |
280 | current->saved_state = TASK_RUNNING; \ |
281 | raw_spin_unlock(¤t->pi_lock); \ |
282 | } while (0); |
283 | |
284 | #define get_current_state() READ_ONCE(current->__state) |
285 | |
286 | /* |
287 | * Define the task command name length as enum, then it can be visible to |
288 | * BPF programs. |
289 | */ |
290 | enum { |
291 | TASK_COMM_LEN = 16, |
292 | }; |
293 | |
294 | extern void scheduler_tick(void); |
295 | |
296 | #define MAX_SCHEDULE_TIMEOUT LONG_MAX |
297 | |
298 | extern long schedule_timeout(long timeout); |
299 | extern long schedule_timeout_interruptible(long timeout); |
300 | extern long schedule_timeout_killable(long timeout); |
301 | extern long schedule_timeout_uninterruptible(long timeout); |
302 | extern long schedule_timeout_idle(long timeout); |
303 | asmlinkage void schedule(void); |
304 | extern void schedule_preempt_disabled(void); |
305 | asmlinkage void preempt_schedule_irq(void); |
306 | #ifdef CONFIG_PREEMPT_RT |
307 | extern void schedule_rtlock(void); |
308 | #endif |
309 | |
310 | extern int __must_check io_schedule_prepare(void); |
311 | extern void io_schedule_finish(int token); |
312 | extern long io_schedule_timeout(long timeout); |
313 | extern void io_schedule(void); |
314 | |
315 | /** |
316 | * struct prev_cputime - snapshot of system and user cputime |
317 | * @utime: time spent in user mode |
318 | * @stime: time spent in system mode |
319 | * @lock: protects the above two fields |
320 | * |
321 | * Stores previous user/system time values such that we can guarantee |
322 | * monotonicity. |
323 | */ |
324 | struct prev_cputime { |
325 | #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE |
326 | u64 utime; |
327 | u64 stime; |
328 | raw_spinlock_t lock; |
329 | #endif |
330 | }; |
331 | |
332 | enum vtime_state { |
333 | /* Task is sleeping or running in a CPU with VTIME inactive: */ |
334 | VTIME_INACTIVE = 0, |
335 | /* Task is idle */ |
336 | VTIME_IDLE, |
337 | /* Task runs in kernelspace in a CPU with VTIME active: */ |
338 | VTIME_SYS, |
339 | /* Task runs in userspace in a CPU with VTIME active: */ |
340 | VTIME_USER, |
341 | /* Task runs as guests in a CPU with VTIME active: */ |
342 | VTIME_GUEST, |
343 | }; |
344 | |
345 | struct vtime { |
346 | seqcount_t seqcount; |
347 | unsigned long long starttime; |
348 | enum vtime_state state; |
349 | unsigned int cpu; |
350 | u64 utime; |
351 | u64 stime; |
352 | u64 gtime; |
353 | }; |
354 | |
355 | /* |
356 | * Utilization clamp constraints. |
357 | * @UCLAMP_MIN: Minimum utilization |
358 | * @UCLAMP_MAX: Maximum utilization |
359 | * @UCLAMP_CNT: Utilization clamp constraints count |
360 | */ |
361 | enum uclamp_id { |
362 | UCLAMP_MIN = 0, |
363 | UCLAMP_MAX, |
364 | UCLAMP_CNT |
365 | }; |
366 | |
367 | #ifdef CONFIG_SMP |
368 | extern struct root_domain def_root_domain; |
369 | extern struct mutex sched_domains_mutex; |
370 | #endif |
371 | |
372 | struct sched_param { |
373 | int sched_priority; |
374 | }; |
375 | |
376 | struct sched_info { |
377 | #ifdef CONFIG_SCHED_INFO |
378 | /* Cumulative counters: */ |
379 | |
380 | /* # of times we have run on this CPU: */ |
381 | unsigned long pcount; |
382 | |
383 | /* Time spent waiting on a runqueue: */ |
384 | unsigned long long run_delay; |
385 | |
386 | /* Timestamps: */ |
387 | |
388 | /* When did we last run on a CPU? */ |
389 | unsigned long long last_arrival; |
390 | |
391 | /* When were we last queued to run? */ |
392 | unsigned long long last_queued; |
393 | |
394 | #endif /* CONFIG_SCHED_INFO */ |
395 | }; |
396 | |
397 | /* |
398 | * Integer metrics need fixed point arithmetic, e.g., sched/fair |
399 | * has a few: load, load_avg, util_avg, freq, and capacity. |
400 | * |
401 | * We define a basic fixed point arithmetic range, and then formalize |
402 | * all these metrics based on that basic range. |
403 | */ |
404 | # define SCHED_FIXEDPOINT_SHIFT 10 |
405 | # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) |
406 | |
407 | /* Increase resolution of cpu_capacity calculations */ |
408 | # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT |
409 | # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) |
410 | |
411 | struct load_weight { |
412 | unsigned long weight; |
413 | u32 inv_weight; |
414 | }; |
415 | |
416 | /** |
417 | * struct util_est - Estimation utilization of FAIR tasks |
418 | * @enqueued: instantaneous estimated utilization of a task/cpu |
419 | * @ewma: the Exponential Weighted Moving Average (EWMA) |
420 | * utilization of a task |
421 | * |
422 | * Support data structure to track an Exponential Weighted Moving Average |
423 | * (EWMA) of a FAIR task's utilization. New samples are added to the moving |
424 | * average each time a task completes an activation. Sample's weight is chosen |
425 | * so that the EWMA will be relatively insensitive to transient changes to the |
426 | * task's workload. |
427 | * |
428 | * The enqueued attribute has a slightly different meaning for tasks and cpus: |
429 | * - task: the task's util_avg at last task dequeue time |
430 | * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU |
431 | * Thus, the util_est.enqueued of a task represents the contribution on the |
432 | * estimated utilization of the CPU where that task is currently enqueued. |
433 | * |
434 | * Only for tasks we track a moving average of the past instantaneous |
435 | * estimated utilization. This allows to absorb sporadic drops in utilization |
436 | * of an otherwise almost periodic task. |
437 | * |
438 | * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg |
439 | * updates. When a task is dequeued, its util_est should not be updated if its |
440 | * util_avg has not been updated in the meantime. |
441 | * This information is mapped into the MSB bit of util_est.enqueued at dequeue |
442 | * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg |
443 | * for a task) it is safe to use MSB. |
444 | */ |
445 | struct util_est { |
446 | unsigned int enqueued; |
447 | unsigned int ewma; |
448 | #define UTIL_EST_WEIGHT_SHIFT 2 |
449 | #define UTIL_AVG_UNCHANGED 0x80000000 |
450 | } __attribute__((__aligned__(sizeof(u64)))); |
451 | |
452 | /* |
453 | * The load/runnable/util_avg accumulates an infinite geometric series |
454 | * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). |
455 | * |
456 | * [load_avg definition] |
457 | * |
458 | * load_avg = runnable% * scale_load_down(load) |
459 | * |
460 | * [runnable_avg definition] |
461 | * |
462 | * runnable_avg = runnable% * SCHED_CAPACITY_SCALE |
463 | * |
464 | * [util_avg definition] |
465 | * |
466 | * util_avg = running% * SCHED_CAPACITY_SCALE |
467 | * |
468 | * where runnable% is the time ratio that a sched_entity is runnable and |
469 | * running% the time ratio that a sched_entity is running. |
470 | * |
471 | * For cfs_rq, they are the aggregated values of all runnable and blocked |
472 | * sched_entities. |
473 | * |
474 | * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU |
475 | * capacity scaling. The scaling is done through the rq_clock_pelt that is used |
476 | * for computing those signals (see update_rq_clock_pelt()) |
477 | * |
478 | * N.B., the above ratios (runnable% and running%) themselves are in the |
479 | * range of [0, 1]. To do fixed point arithmetics, we therefore scale them |
480 | * to as large a range as necessary. This is for example reflected by |
481 | * util_avg's SCHED_CAPACITY_SCALE. |
482 | * |
483 | * [Overflow issue] |
484 | * |
485 | * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities |
486 | * with the highest load (=88761), always runnable on a single cfs_rq, |
487 | * and should not overflow as the number already hits PID_MAX_LIMIT. |
488 | * |
489 | * For all other cases (including 32-bit kernels), struct load_weight's |
490 | * weight will overflow first before we do, because: |
491 | * |
492 | * Max(load_avg) <= Max(load.weight) |
493 | * |
494 | * Then it is the load_weight's responsibility to consider overflow |
495 | * issues. |
496 | */ |
497 | struct sched_avg { |
498 | u64 last_update_time; |
499 | u64 load_sum; |
500 | u64 runnable_sum; |
501 | u32 util_sum; |
502 | u32 period_contrib; |
503 | unsigned long load_avg; |
504 | unsigned long runnable_avg; |
505 | unsigned long util_avg; |
506 | struct util_est util_est; |
507 | } ____cacheline_aligned; |
508 | |
509 | struct sched_statistics { |
510 | #ifdef CONFIG_SCHEDSTATS |
511 | u64 wait_start; |
512 | u64 wait_max; |
513 | u64 wait_count; |
514 | u64 wait_sum; |
515 | u64 iowait_count; |
516 | u64 iowait_sum; |
517 | |
518 | u64 sleep_start; |
519 | u64 sleep_max; |
520 | s64 sum_sleep_runtime; |
521 | |
522 | u64 block_start; |
523 | u64 block_max; |
524 | s64 sum_block_runtime; |
525 | |
526 | u64 exec_max; |
527 | u64 slice_max; |
528 | |
529 | u64 nr_migrations_cold; |
530 | u64 nr_failed_migrations_affine; |
531 | u64 nr_failed_migrations_running; |
532 | u64 nr_failed_migrations_hot; |
533 | u64 nr_forced_migrations; |
534 | |
535 | u64 nr_wakeups; |
536 | u64 nr_wakeups_sync; |
537 | u64 nr_wakeups_migrate; |
538 | u64 nr_wakeups_local; |
539 | u64 nr_wakeups_remote; |
540 | u64 nr_wakeups_affine; |
541 | u64 nr_wakeups_affine_attempts; |
542 | u64 nr_wakeups_passive; |
543 | u64 nr_wakeups_idle; |
544 | |
545 | #ifdef CONFIG_SCHED_CORE |
546 | u64 core_forceidle_sum; |
547 | #endif |
548 | #endif /* CONFIG_SCHEDSTATS */ |
549 | } ____cacheline_aligned; |
550 | |
551 | struct sched_entity { |
552 | /* For load-balancing: */ |
553 | struct load_weight load; |
554 | struct rb_node run_node; |
555 | u64 deadline; |
556 | u64 min_deadline; |
557 | |
558 | struct list_head group_node; |
559 | unsigned int on_rq; |
560 | |
561 | u64 exec_start; |
562 | u64 sum_exec_runtime; |
563 | u64 prev_sum_exec_runtime; |
564 | u64 vruntime; |
565 | s64 vlag; |
566 | u64 slice; |
567 | |
568 | u64 nr_migrations; |
569 | |
570 | #ifdef CONFIG_FAIR_GROUP_SCHED |
571 | int depth; |
572 | struct sched_entity *parent; |
573 | /* rq on which this entity is (to be) queued: */ |
574 | struct cfs_rq *cfs_rq; |
575 | /* rq "owned" by this entity/group: */ |
576 | struct cfs_rq *my_q; |
577 | /* cached value of my_q->h_nr_running */ |
578 | unsigned long runnable_weight; |
579 | #endif |
580 | |
581 | #ifdef CONFIG_SMP |
582 | /* |
583 | * Per entity load average tracking. |
584 | * |
585 | * Put into separate cache line so it does not |
586 | * collide with read-mostly values above. |
587 | */ |
588 | struct sched_avg avg; |
589 | #endif |
590 | }; |
591 | |
592 | struct sched_rt_entity { |
593 | struct list_head run_list; |
594 | unsigned long timeout; |
595 | unsigned long watchdog_stamp; |
596 | unsigned int time_slice; |
597 | unsigned short on_rq; |
598 | unsigned short on_list; |
599 | |
600 | struct sched_rt_entity *back; |
601 | #ifdef CONFIG_RT_GROUP_SCHED |
602 | struct sched_rt_entity *parent; |
603 | /* rq on which this entity is (to be) queued: */ |
604 | struct rt_rq *rt_rq; |
605 | /* rq "owned" by this entity/group: */ |
606 | struct rt_rq *my_q; |
607 | #endif |
608 | } __randomize_layout; |
609 | |
610 | struct sched_dl_entity { |
611 | struct rb_node rb_node; |
612 | |
613 | /* |
614 | * Original scheduling parameters. Copied here from sched_attr |
615 | * during sched_setattr(), they will remain the same until |
616 | * the next sched_setattr(). |
617 | */ |
618 | u64 dl_runtime; /* Maximum runtime for each instance */ |
619 | u64 dl_deadline; /* Relative deadline of each instance */ |
620 | u64 dl_period; /* Separation of two instances (period) */ |
621 | u64 dl_bw; /* dl_runtime / dl_period */ |
622 | u64 dl_density; /* dl_runtime / dl_deadline */ |
623 | |
624 | /* |
625 | * Actual scheduling parameters. Initialized with the values above, |
626 | * they are continuously updated during task execution. Note that |
627 | * the remaining runtime could be < 0 in case we are in overrun. |
628 | */ |
629 | s64 runtime; /* Remaining runtime for this instance */ |
630 | u64 deadline; /* Absolute deadline for this instance */ |
631 | unsigned int flags; /* Specifying the scheduler behaviour */ |
632 | |
633 | /* |
634 | * Some bool flags: |
635 | * |
636 | * @dl_throttled tells if we exhausted the runtime. If so, the |
637 | * task has to wait for a replenishment to be performed at the |
638 | * next firing of dl_timer. |
639 | * |
640 | * @dl_yielded tells if task gave up the CPU before consuming |
641 | * all its available runtime during the last job. |
642 | * |
643 | * @dl_non_contending tells if the task is inactive while still |
644 | * contributing to the active utilization. In other words, it |
645 | * indicates if the inactive timer has been armed and its handler |
646 | * has not been executed yet. This flag is useful to avoid race |
647 | * conditions between the inactive timer handler and the wakeup |
648 | * code. |
649 | * |
650 | * @dl_overrun tells if the task asked to be informed about runtime |
651 | * overruns. |
652 | */ |
653 | unsigned int dl_throttled : 1; |
654 | unsigned int dl_yielded : 1; |
655 | unsigned int dl_non_contending : 1; |
656 | unsigned int dl_overrun : 1; |
657 | |
658 | /* |
659 | * Bandwidth enforcement timer. Each -deadline task has its |
660 | * own bandwidth to be enforced, thus we need one timer per task. |
661 | */ |
662 | struct hrtimer dl_timer; |
663 | |
664 | /* |
665 | * Inactive timer, responsible for decreasing the active utilization |
666 | * at the "0-lag time". When a -deadline task blocks, it contributes |
667 | * to GRUB's active utilization until the "0-lag time", hence a |
668 | * timer is needed to decrease the active utilization at the correct |
669 | * time. |
670 | */ |
671 | struct hrtimer inactive_timer; |
672 | |
673 | #ifdef CONFIG_RT_MUTEXES |
674 | /* |
675 | * Priority Inheritance. When a DEADLINE scheduling entity is boosted |
676 | * pi_se points to the donor, otherwise points to the dl_se it belongs |
677 | * to (the original one/itself). |
678 | */ |
679 | struct sched_dl_entity *pi_se; |
680 | #endif |
681 | }; |
682 | |
683 | #ifdef CONFIG_UCLAMP_TASK |
684 | /* Number of utilization clamp buckets (shorter alias) */ |
685 | #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT |
686 | |
687 | /* |
688 | * Utilization clamp for a scheduling entity |
689 | * @value: clamp value "assigned" to a se |
690 | * @bucket_id: bucket index corresponding to the "assigned" value |
691 | * @active: the se is currently refcounted in a rq's bucket |
692 | * @user_defined: the requested clamp value comes from user-space |
693 | * |
694 | * The bucket_id is the index of the clamp bucket matching the clamp value |
695 | * which is pre-computed and stored to avoid expensive integer divisions from |
696 | * the fast path. |
697 | * |
698 | * The active bit is set whenever a task has got an "effective" value assigned, |
699 | * which can be different from the clamp value "requested" from user-space. |
700 | * This allows to know a task is refcounted in the rq's bucket corresponding |
701 | * to the "effective" bucket_id. |
702 | * |
703 | * The user_defined bit is set whenever a task has got a task-specific clamp |
704 | * value requested from userspace, i.e. the system defaults apply to this task |
705 | * just as a restriction. This allows to relax default clamps when a less |
706 | * restrictive task-specific value has been requested, thus allowing to |
707 | * implement a "nice" semantic. For example, a task running with a 20% |
708 | * default boost can still drop its own boosting to 0%. |
709 | */ |
710 | struct uclamp_se { |
711 | unsigned int value : bits_per(SCHED_CAPACITY_SCALE); |
712 | unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); |
713 | unsigned int active : 1; |
714 | unsigned int user_defined : 1; |
715 | }; |
716 | #endif /* CONFIG_UCLAMP_TASK */ |
717 | |
718 | union rcu_special { |
719 | struct { |
720 | u8 blocked; |
721 | u8 need_qs; |
722 | u8 exp_hint; /* Hint for performance. */ |
723 | u8 need_mb; /* Readers need smp_mb(). */ |
724 | } b; /* Bits. */ |
725 | u32 s; /* Set of bits. */ |
726 | }; |
727 | |
728 | enum perf_event_task_context { |
729 | perf_invalid_context = -1, |
730 | perf_hw_context = 0, |
731 | perf_sw_context, |
732 | perf_nr_task_contexts, |
733 | }; |
734 | |
735 | struct wake_q_node { |
736 | struct wake_q_node *next; |
737 | }; |
738 | |
739 | struct kmap_ctrl { |
740 | #ifdef CONFIG_KMAP_LOCAL |
741 | int idx; |
742 | pte_t pteval[KM_MAX_IDX]; |
743 | #endif |
744 | }; |
745 | |
746 | struct task_struct { |
747 | #ifdef CONFIG_THREAD_INFO_IN_TASK |
748 | /* |
749 | * For reasons of header soup (see current_thread_info()), this |
750 | * must be the first element of task_struct. |
751 | */ |
752 | struct thread_info thread_info; |
753 | #endif |
754 | unsigned int __state; |
755 | |
756 | /* saved state for "spinlock sleepers" */ |
757 | unsigned int saved_state; |
758 | |
759 | /* |
760 | * This begins the randomizable portion of task_struct. Only |
761 | * scheduling-critical items should be added above here. |
762 | */ |
763 | randomized_struct_fields_start |
764 | |
765 | void *stack; |
766 | refcount_t usage; |
767 | /* Per task flags (PF_*), defined further below: */ |
768 | unsigned int flags; |
769 | unsigned int ptrace; |
770 | |
771 | #ifdef CONFIG_SMP |
772 | int on_cpu; |
773 | struct __call_single_node wake_entry; |
774 | unsigned int wakee_flips; |
775 | unsigned long wakee_flip_decay_ts; |
776 | struct task_struct *last_wakee; |
777 | |
778 | /* |
779 | * recent_used_cpu is initially set as the last CPU used by a task |
780 | * that wakes affine another task. Waker/wakee relationships can |
781 | * push tasks around a CPU where each wakeup moves to the next one. |
782 | * Tracking a recently used CPU allows a quick search for a recently |
783 | * used CPU that may be idle. |
784 | */ |
785 | int recent_used_cpu; |
786 | int wake_cpu; |
787 | #endif |
788 | int on_rq; |
789 | |
790 | int prio; |
791 | int static_prio; |
792 | int normal_prio; |
793 | unsigned int rt_priority; |
794 | |
795 | struct sched_entity se; |
796 | struct sched_rt_entity rt; |
797 | struct sched_dl_entity dl; |
798 | const struct sched_class *sched_class; |
799 | |
800 | #ifdef CONFIG_SCHED_CORE |
801 | struct rb_node core_node; |
802 | unsigned long core_cookie; |
803 | unsigned int core_occupation; |
804 | #endif |
805 | |
806 | #ifdef CONFIG_CGROUP_SCHED |
807 | struct task_group *sched_task_group; |
808 | #endif |
809 | |
810 | #ifdef CONFIG_UCLAMP_TASK |
811 | /* |
812 | * Clamp values requested for a scheduling entity. |
813 | * Must be updated with task_rq_lock() held. |
814 | */ |
815 | struct uclamp_se uclamp_req[UCLAMP_CNT]; |
816 | /* |
817 | * Effective clamp values used for a scheduling entity. |
818 | * Must be updated with task_rq_lock() held. |
819 | */ |
820 | struct uclamp_se uclamp[UCLAMP_CNT]; |
821 | #endif |
822 | |
823 | struct sched_statistics stats; |
824 | |
825 | #ifdef CONFIG_PREEMPT_NOTIFIERS |
826 | /* List of struct preempt_notifier: */ |
827 | struct hlist_head preempt_notifiers; |
828 | #endif |
829 | |
830 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
831 | unsigned int btrace_seq; |
832 | #endif |
833 | |
834 | unsigned int policy; |
835 | int nr_cpus_allowed; |
836 | const cpumask_t *cpus_ptr; |
837 | cpumask_t *user_cpus_ptr; |
838 | cpumask_t cpus_mask; |
839 | void *migration_pending; |
840 | #ifdef CONFIG_SMP |
841 | unsigned short migration_disabled; |
842 | #endif |
843 | unsigned short migration_flags; |
844 | |
845 | #ifdef CONFIG_PREEMPT_RCU |
846 | int rcu_read_lock_nesting; |
847 | union rcu_special rcu_read_unlock_special; |
848 | struct list_head rcu_node_entry; |
849 | struct rcu_node *rcu_blocked_node; |
850 | #endif /* #ifdef CONFIG_PREEMPT_RCU */ |
851 | |
852 | #ifdef CONFIG_TASKS_RCU |
853 | unsigned long rcu_tasks_nvcsw; |
854 | u8 rcu_tasks_holdout; |
855 | u8 rcu_tasks_idx; |
856 | int rcu_tasks_idle_cpu; |
857 | struct list_head rcu_tasks_holdout_list; |
858 | #endif /* #ifdef CONFIG_TASKS_RCU */ |
859 | |
860 | #ifdef CONFIG_TASKS_TRACE_RCU |
861 | int trc_reader_nesting; |
862 | int trc_ipi_to_cpu; |
863 | union rcu_special trc_reader_special; |
864 | struct list_head trc_holdout_list; |
865 | struct list_head trc_blkd_node; |
866 | int trc_blkd_cpu; |
867 | #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ |
868 | |
869 | struct sched_info sched_info; |
870 | |
871 | struct list_head tasks; |
872 | #ifdef CONFIG_SMP |
873 | struct plist_node pushable_tasks; |
874 | struct rb_node pushable_dl_tasks; |
875 | #endif |
876 | |
877 | struct mm_struct *mm; |
878 | struct mm_struct *active_mm; |
879 | struct address_space *faults_disabled_mapping; |
880 | |
881 | int exit_state; |
882 | int exit_code; |
883 | int exit_signal; |
884 | /* The signal sent when the parent dies: */ |
885 | int pdeath_signal; |
886 | /* JOBCTL_*, siglock protected: */ |
887 | unsigned long jobctl; |
888 | |
889 | /* Used for emulating ABI behavior of previous Linux versions: */ |
890 | unsigned int personality; |
891 | |
892 | /* Scheduler bits, serialized by scheduler locks: */ |
893 | unsigned sched_reset_on_fork:1; |
894 | unsigned sched_contributes_to_load:1; |
895 | unsigned sched_migrated:1; |
896 | |
897 | /* Force alignment to the next boundary: */ |
898 | unsigned :0; |
899 | |
900 | /* Unserialized, strictly 'current' */ |
901 | |
902 | /* |
903 | * This field must not be in the scheduler word above due to wakelist |
904 | * queueing no longer being serialized by p->on_cpu. However: |
905 | * |
906 | * p->XXX = X; ttwu() |
907 | * schedule() if (p->on_rq && ..) // false |
908 | * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true |
909 | * deactivate_task() ttwu_queue_wakelist()) |
910 | * p->on_rq = 0; p->sched_remote_wakeup = Y; |
911 | * |
912 | * guarantees all stores of 'current' are visible before |
913 | * ->sched_remote_wakeup gets used, so it can be in this word. |
914 | */ |
915 | unsigned sched_remote_wakeup:1; |
916 | #ifdef CONFIG_RT_MUTEXES |
917 | unsigned sched_rt_mutex:1; |
918 | #endif |
919 | |
920 | /* Bit to tell LSMs we're in execve(): */ |
921 | unsigned in_execve:1; |
922 | unsigned in_iowait:1; |
923 | #ifndef TIF_RESTORE_SIGMASK |
924 | unsigned restore_sigmask:1; |
925 | #endif |
926 | #ifdef CONFIG_MEMCG |
927 | unsigned in_user_fault:1; |
928 | #endif |
929 | #ifdef CONFIG_LRU_GEN |
930 | /* whether the LRU algorithm may apply to this access */ |
931 | unsigned in_lru_fault:1; |
932 | #endif |
933 | #ifdef CONFIG_COMPAT_BRK |
934 | unsigned brk_randomized:1; |
935 | #endif |
936 | #ifdef CONFIG_CGROUPS |
937 | /* disallow userland-initiated cgroup migration */ |
938 | unsigned no_cgroup_migration:1; |
939 | /* task is frozen/stopped (used by the cgroup freezer) */ |
940 | unsigned frozen:1; |
941 | #endif |
942 | #ifdef CONFIG_BLK_CGROUP |
943 | unsigned use_memdelay:1; |
944 | #endif |
945 | #ifdef CONFIG_PSI |
946 | /* Stalled due to lack of memory */ |
947 | unsigned in_memstall:1; |
948 | #endif |
949 | #ifdef CONFIG_PAGE_OWNER |
950 | /* Used by page_owner=on to detect recursion in page tracking. */ |
951 | unsigned in_page_owner:1; |
952 | #endif |
953 | #ifdef CONFIG_EVENTFD |
954 | /* Recursion prevention for eventfd_signal() */ |
955 | unsigned in_eventfd:1; |
956 | #endif |
957 | #ifdef CONFIG_IOMMU_SVA |
958 | unsigned pasid_activated:1; |
959 | #endif |
960 | #ifdef CONFIG_CPU_SUP_INTEL |
961 | unsigned reported_split_lock:1; |
962 | #endif |
963 | #ifdef CONFIG_TASK_DELAY_ACCT |
964 | /* delay due to memory thrashing */ |
965 | unsigned in_thrashing:1; |
966 | #endif |
967 | |
968 | unsigned long atomic_flags; /* Flags requiring atomic access. */ |
969 | |
970 | struct restart_block restart_block; |
971 | |
972 | pid_t pid; |
973 | pid_t tgid; |
974 | |
975 | #ifdef CONFIG_STACKPROTECTOR |
976 | /* Canary value for the -fstack-protector GCC feature: */ |
977 | unsigned long stack_canary; |
978 | #endif |
979 | /* |
980 | * Pointers to the (original) parent process, youngest child, younger sibling, |
981 | * older sibling, respectively. (p->father can be replaced with |
982 | * p->real_parent->pid) |
983 | */ |
984 | |
985 | /* Real parent process: */ |
986 | struct task_struct __rcu *real_parent; |
987 | |
988 | /* Recipient of SIGCHLD, wait4() reports: */ |
989 | struct task_struct __rcu *parent; |
990 | |
991 | /* |
992 | * Children/sibling form the list of natural children: |
993 | */ |
994 | struct list_head children; |
995 | struct list_head sibling; |
996 | struct task_struct *group_leader; |
997 | |
998 | /* |
999 | * 'ptraced' is the list of tasks this task is using ptrace() on. |
1000 | * |
1001 | * This includes both natural children and PTRACE_ATTACH targets. |
1002 | * 'ptrace_entry' is this task's link on the p->parent->ptraced list. |
1003 | */ |
1004 | struct list_head ptraced; |
1005 | struct list_head ptrace_entry; |
1006 | |
1007 | /* PID/PID hash table linkage. */ |
1008 | struct pid *thread_pid; |
1009 | struct hlist_node pid_links[PIDTYPE_MAX]; |
1010 | struct list_head thread_node; |
1011 | |
1012 | struct completion *vfork_done; |
1013 | |
1014 | /* CLONE_CHILD_SETTID: */ |
1015 | int __user *set_child_tid; |
1016 | |
1017 | /* CLONE_CHILD_CLEARTID: */ |
1018 | int __user *clear_child_tid; |
1019 | |
1020 | /* PF_KTHREAD | PF_IO_WORKER */ |
1021 | void *worker_private; |
1022 | |
1023 | u64 utime; |
1024 | u64 stime; |
1025 | #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME |
1026 | u64 utimescaled; |
1027 | u64 stimescaled; |
1028 | #endif |
1029 | u64 gtime; |
1030 | struct prev_cputime prev_cputime; |
1031 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN |
1032 | struct vtime vtime; |
1033 | #endif |
1034 | |
1035 | #ifdef CONFIG_NO_HZ_FULL |
1036 | atomic_t tick_dep_mask; |
1037 | #endif |
1038 | /* Context switch counts: */ |
1039 | unsigned long nvcsw; |
1040 | unsigned long nivcsw; |
1041 | |
1042 | /* Monotonic time in nsecs: */ |
1043 | u64 start_time; |
1044 | |
1045 | /* Boot based time in nsecs: */ |
1046 | u64 start_boottime; |
1047 | |
1048 | /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ |
1049 | unsigned long min_flt; |
1050 | unsigned long maj_flt; |
1051 | |
1052 | /* Empty if CONFIG_POSIX_CPUTIMERS=n */ |
1053 | struct posix_cputimers posix_cputimers; |
1054 | |
1055 | #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK |
1056 | struct posix_cputimers_work posix_cputimers_work; |
1057 | #endif |
1058 | |
1059 | /* Process credentials: */ |
1060 | |
1061 | /* Tracer's credentials at attach: */ |
1062 | const struct cred __rcu *ptracer_cred; |
1063 | |
1064 | /* Objective and real subjective task credentials (COW): */ |
1065 | const struct cred __rcu *real_cred; |
1066 | |
1067 | /* Effective (overridable) subjective task credentials (COW): */ |
1068 | const struct cred __rcu *cred; |
1069 | |
1070 | #ifdef CONFIG_KEYS |
1071 | /* Cached requested key. */ |
1072 | struct key *cached_requested_key; |
1073 | #endif |
1074 | |
1075 | /* |
1076 | * executable name, excluding path. |
1077 | * |
1078 | * - normally initialized setup_new_exec() |
1079 | * - access it with [gs]et_task_comm() |
1080 | * - lock it with task_lock() |
1081 | */ |
1082 | char comm[TASK_COMM_LEN]; |
1083 | |
1084 | struct nameidata *nameidata; |
1085 | |
1086 | #ifdef CONFIG_SYSVIPC |
1087 | struct sysv_sem sysvsem; |
1088 | struct sysv_shm sysvshm; |
1089 | #endif |
1090 | #ifdef CONFIG_DETECT_HUNG_TASK |
1091 | unsigned long last_switch_count; |
1092 | unsigned long last_switch_time; |
1093 | #endif |
1094 | /* Filesystem information: */ |
1095 | struct fs_struct *fs; |
1096 | |
1097 | /* Open file information: */ |
1098 | struct files_struct *files; |
1099 | |
1100 | #ifdef CONFIG_IO_URING |
1101 | struct io_uring_task *io_uring; |
1102 | #endif |
1103 | |
1104 | /* Namespaces: */ |
1105 | struct nsproxy *nsproxy; |
1106 | |
1107 | /* Signal handlers: */ |
1108 | struct signal_struct *signal; |
1109 | struct sighand_struct __rcu *sighand; |
1110 | sigset_t blocked; |
1111 | sigset_t real_blocked; |
1112 | /* Restored if set_restore_sigmask() was used: */ |
1113 | sigset_t saved_sigmask; |
1114 | struct sigpending pending; |
1115 | unsigned long sas_ss_sp; |
1116 | size_t sas_ss_size; |
1117 | unsigned int sas_ss_flags; |
1118 | |
1119 | struct callback_head *task_works; |
1120 | |
1121 | #ifdef CONFIG_AUDIT |
1122 | #ifdef CONFIG_AUDITSYSCALL |
1123 | struct audit_context *audit_context; |
1124 | #endif |
1125 | kuid_t loginuid; |
1126 | unsigned int sessionid; |
1127 | #endif |
1128 | struct seccomp seccomp; |
1129 | struct syscall_user_dispatch syscall_dispatch; |
1130 | |
1131 | /* Thread group tracking: */ |
1132 | u64 parent_exec_id; |
1133 | u64 self_exec_id; |
1134 | |
1135 | /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ |
1136 | spinlock_t alloc_lock; |
1137 | |
1138 | /* Protection of the PI data structures: */ |
1139 | raw_spinlock_t pi_lock; |
1140 | |
1141 | struct wake_q_node wake_q; |
1142 | |
1143 | #ifdef CONFIG_RT_MUTEXES |
1144 | /* PI waiters blocked on a rt_mutex held by this task: */ |
1145 | struct rb_root_cached pi_waiters; |
1146 | /* Updated under owner's pi_lock and rq lock */ |
1147 | struct task_struct *pi_top_task; |
1148 | /* Deadlock detection and priority inheritance handling: */ |
1149 | struct rt_mutex_waiter *pi_blocked_on; |
1150 | #endif |
1151 | |
1152 | #ifdef CONFIG_DEBUG_MUTEXES |
1153 | /* Mutex deadlock detection: */ |
1154 | struct mutex_waiter *blocked_on; |
1155 | #endif |
1156 | |
1157 | #ifdef CONFIG_DEBUG_ATOMIC_SLEEP |
1158 | int non_block_count; |
1159 | #endif |
1160 | |
1161 | #ifdef CONFIG_TRACE_IRQFLAGS |
1162 | struct irqtrace_events irqtrace; |
1163 | unsigned int hardirq_threaded; |
1164 | u64 hardirq_chain_key; |
1165 | int softirqs_enabled; |
1166 | int softirq_context; |
1167 | int irq_config; |
1168 | #endif |
1169 | #ifdef CONFIG_PREEMPT_RT |
1170 | int softirq_disable_cnt; |
1171 | #endif |
1172 | |
1173 | #ifdef CONFIG_LOCKDEP |
1174 | # define MAX_LOCK_DEPTH 48UL |
1175 | u64 curr_chain_key; |
1176 | int lockdep_depth; |
1177 | unsigned int lockdep_recursion; |
1178 | struct held_lock held_locks[MAX_LOCK_DEPTH]; |
1179 | #endif |
1180 | |
1181 | #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) |
1182 | unsigned int in_ubsan; |
1183 | #endif |
1184 | |
1185 | /* Journalling filesystem info: */ |
1186 | void *journal_info; |
1187 | |
1188 | /* Stacked block device info: */ |
1189 | struct bio_list *bio_list; |
1190 | |
1191 | /* Stack plugging: */ |
1192 | struct blk_plug *plug; |
1193 | |
1194 | /* VM state: */ |
1195 | struct reclaim_state *reclaim_state; |
1196 | |
1197 | struct io_context *io_context; |
1198 | |
1199 | #ifdef CONFIG_COMPACTION |
1200 | struct capture_control *capture_control; |
1201 | #endif |
1202 | /* Ptrace state: */ |
1203 | unsigned long ptrace_message; |
1204 | kernel_siginfo_t *last_siginfo; |
1205 | |
1206 | struct task_io_accounting ioac; |
1207 | #ifdef CONFIG_PSI |
1208 | /* Pressure stall state */ |
1209 | unsigned int psi_flags; |
1210 | #endif |
1211 | #ifdef CONFIG_TASK_XACCT |
1212 | /* Accumulated RSS usage: */ |
1213 | u64 ; |
1214 | /* Accumulated virtual memory usage: */ |
1215 | u64 acct_vm_mem1; |
1216 | /* stime + utime since last update: */ |
1217 | u64 acct_timexpd; |
1218 | #endif |
1219 | #ifdef CONFIG_CPUSETS |
1220 | /* Protected by ->alloc_lock: */ |
1221 | nodemask_t mems_allowed; |
1222 | /* Sequence number to catch updates: */ |
1223 | seqcount_spinlock_t mems_allowed_seq; |
1224 | int cpuset_mem_spread_rotor; |
1225 | int cpuset_slab_spread_rotor; |
1226 | #endif |
1227 | #ifdef CONFIG_CGROUPS |
1228 | /* Control Group info protected by css_set_lock: */ |
1229 | struct css_set __rcu *cgroups; |
1230 | /* cg_list protected by css_set_lock and tsk->alloc_lock: */ |
1231 | struct list_head cg_list; |
1232 | #endif |
1233 | #ifdef CONFIG_X86_CPU_RESCTRL |
1234 | u32 closid; |
1235 | u32 rmid; |
1236 | #endif |
1237 | #ifdef CONFIG_FUTEX |
1238 | struct robust_list_head __user *robust_list; |
1239 | #ifdef CONFIG_COMPAT |
1240 | struct compat_robust_list_head __user *compat_robust_list; |
1241 | #endif |
1242 | struct list_head pi_state_list; |
1243 | struct futex_pi_state *pi_state_cache; |
1244 | struct mutex futex_exit_mutex; |
1245 | unsigned int futex_state; |
1246 | #endif |
1247 | #ifdef CONFIG_PERF_EVENTS |
1248 | struct perf_event_context *perf_event_ctxp; |
1249 | struct mutex perf_event_mutex; |
1250 | struct list_head perf_event_list; |
1251 | #endif |
1252 | #ifdef CONFIG_DEBUG_PREEMPT |
1253 | unsigned long preempt_disable_ip; |
1254 | #endif |
1255 | #ifdef CONFIG_NUMA |
1256 | /* Protected by alloc_lock: */ |
1257 | struct mempolicy *mempolicy; |
1258 | short il_prev; |
1259 | short pref_node_fork; |
1260 | #endif |
1261 | #ifdef CONFIG_NUMA_BALANCING |
1262 | int numa_scan_seq; |
1263 | unsigned int numa_scan_period; |
1264 | unsigned int numa_scan_period_max; |
1265 | int numa_preferred_nid; |
1266 | unsigned long numa_migrate_retry; |
1267 | /* Migration stamp: */ |
1268 | u64 node_stamp; |
1269 | u64 last_task_numa_placement; |
1270 | u64 last_sum_exec_runtime; |
1271 | struct callback_head numa_work; |
1272 | |
1273 | /* |
1274 | * This pointer is only modified for current in syscall and |
1275 | * pagefault context (and for tasks being destroyed), so it can be read |
1276 | * from any of the following contexts: |
1277 | * - RCU read-side critical section |
1278 | * - current->numa_group from everywhere |
1279 | * - task's runqueue locked, task not running |
1280 | */ |
1281 | struct numa_group __rcu *numa_group; |
1282 | |
1283 | /* |
1284 | * numa_faults is an array split into four regions: |
1285 | * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer |
1286 | * in this precise order. |
1287 | * |
1288 | * faults_memory: Exponential decaying average of faults on a per-node |
1289 | * basis. Scheduling placement decisions are made based on these |
1290 | * counts. The values remain static for the duration of a PTE scan. |
1291 | * faults_cpu: Track the nodes the process was running on when a NUMA |
1292 | * hinting fault was incurred. |
1293 | * faults_memory_buffer and faults_cpu_buffer: Record faults per node |
1294 | * during the current scan window. When the scan completes, the counts |
1295 | * in faults_memory and faults_cpu decay and these values are copied. |
1296 | */ |
1297 | unsigned long *numa_faults; |
1298 | unsigned long total_numa_faults; |
1299 | |
1300 | /* |
1301 | * numa_faults_locality tracks if faults recorded during the last |
1302 | * scan window were remote/local or failed to migrate. The task scan |
1303 | * period is adapted based on the locality of the faults with different |
1304 | * weights depending on whether they were shared or private faults |
1305 | */ |
1306 | unsigned long numa_faults_locality[3]; |
1307 | |
1308 | unsigned long numa_pages_migrated; |
1309 | #endif /* CONFIG_NUMA_BALANCING */ |
1310 | |
1311 | #ifdef CONFIG_RSEQ |
1312 | struct rseq __user *rseq; |
1313 | u32 rseq_len; |
1314 | u32 rseq_sig; |
1315 | /* |
1316 | * RmW on rseq_event_mask must be performed atomically |
1317 | * with respect to preemption. |
1318 | */ |
1319 | unsigned long rseq_event_mask; |
1320 | #endif |
1321 | |
1322 | #ifdef CONFIG_SCHED_MM_CID |
1323 | int mm_cid; /* Current cid in mm */ |
1324 | int last_mm_cid; /* Most recent cid in mm */ |
1325 | int migrate_from_cpu; |
1326 | int mm_cid_active; /* Whether cid bitmap is active */ |
1327 | struct callback_head cid_work; |
1328 | #endif |
1329 | |
1330 | struct tlbflush_unmap_batch tlb_ubc; |
1331 | |
1332 | /* Cache last used pipe for splice(): */ |
1333 | struct pipe_inode_info *splice_pipe; |
1334 | |
1335 | struct page_frag task_frag; |
1336 | |
1337 | #ifdef CONFIG_TASK_DELAY_ACCT |
1338 | struct task_delay_info *delays; |
1339 | #endif |
1340 | |
1341 | #ifdef CONFIG_FAULT_INJECTION |
1342 | int make_it_fail; |
1343 | unsigned int fail_nth; |
1344 | #endif |
1345 | /* |
1346 | * When (nr_dirtied >= nr_dirtied_pause), it's time to call |
1347 | * balance_dirty_pages() for a dirty throttling pause: |
1348 | */ |
1349 | int nr_dirtied; |
1350 | int nr_dirtied_pause; |
1351 | /* Start of a write-and-pause period: */ |
1352 | unsigned long dirty_paused_when; |
1353 | |
1354 | #ifdef CONFIG_LATENCYTOP |
1355 | int latency_record_count; |
1356 | struct latency_record latency_record[LT_SAVECOUNT]; |
1357 | #endif |
1358 | /* |
1359 | * Time slack values; these are used to round up poll() and |
1360 | * select() etc timeout values. These are in nanoseconds. |
1361 | */ |
1362 | u64 timer_slack_ns; |
1363 | u64 default_timer_slack_ns; |
1364 | |
1365 | #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) |
1366 | unsigned int kasan_depth; |
1367 | #endif |
1368 | |
1369 | #ifdef CONFIG_KCSAN |
1370 | struct kcsan_ctx kcsan_ctx; |
1371 | #ifdef CONFIG_TRACE_IRQFLAGS |
1372 | struct irqtrace_events kcsan_save_irqtrace; |
1373 | #endif |
1374 | #ifdef CONFIG_KCSAN_WEAK_MEMORY |
1375 | int kcsan_stack_depth; |
1376 | #endif |
1377 | #endif |
1378 | |
1379 | #ifdef CONFIG_KMSAN |
1380 | struct kmsan_ctx kmsan_ctx; |
1381 | #endif |
1382 | |
1383 | #if IS_ENABLED(CONFIG_KUNIT) |
1384 | struct kunit *kunit_test; |
1385 | #endif |
1386 | |
1387 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1388 | /* Index of current stored address in ret_stack: */ |
1389 | int curr_ret_stack; |
1390 | int curr_ret_depth; |
1391 | |
1392 | /* Stack of return addresses for return function tracing: */ |
1393 | struct ftrace_ret_stack *ret_stack; |
1394 | |
1395 | /* Timestamp for last schedule: */ |
1396 | unsigned long long ftrace_timestamp; |
1397 | |
1398 | /* |
1399 | * Number of functions that haven't been traced |
1400 | * because of depth overrun: |
1401 | */ |
1402 | atomic_t trace_overrun; |
1403 | |
1404 | /* Pause tracing: */ |
1405 | atomic_t tracing_graph_pause; |
1406 | #endif |
1407 | |
1408 | #ifdef CONFIG_TRACING |
1409 | /* Bitmask and counter of trace recursion: */ |
1410 | unsigned long trace_recursion; |
1411 | #endif /* CONFIG_TRACING */ |
1412 | |
1413 | #ifdef CONFIG_KCOV |
1414 | /* See kernel/kcov.c for more details. */ |
1415 | |
1416 | /* Coverage collection mode enabled for this task (0 if disabled): */ |
1417 | unsigned int kcov_mode; |
1418 | |
1419 | /* Size of the kcov_area: */ |
1420 | unsigned int kcov_size; |
1421 | |
1422 | /* Buffer for coverage collection: */ |
1423 | void *kcov_area; |
1424 | |
1425 | /* KCOV descriptor wired with this task or NULL: */ |
1426 | struct kcov *kcov; |
1427 | |
1428 | /* KCOV common handle for remote coverage collection: */ |
1429 | u64 kcov_handle; |
1430 | |
1431 | /* KCOV sequence number: */ |
1432 | int kcov_sequence; |
1433 | |
1434 | /* Collect coverage from softirq context: */ |
1435 | unsigned int kcov_softirq; |
1436 | #endif |
1437 | |
1438 | #ifdef CONFIG_MEMCG |
1439 | struct mem_cgroup *memcg_in_oom; |
1440 | gfp_t memcg_oom_gfp_mask; |
1441 | int memcg_oom_order; |
1442 | |
1443 | /* Number of pages to reclaim on returning to userland: */ |
1444 | unsigned int memcg_nr_pages_over_high; |
1445 | |
1446 | /* Used by memcontrol for targeted memcg charge: */ |
1447 | struct mem_cgroup *active_memcg; |
1448 | #endif |
1449 | |
1450 | #ifdef CONFIG_MEMCG_KMEM |
1451 | struct obj_cgroup *objcg; |
1452 | #endif |
1453 | |
1454 | #ifdef CONFIG_BLK_CGROUP |
1455 | struct gendisk *throttle_disk; |
1456 | #endif |
1457 | |
1458 | #ifdef CONFIG_UPROBES |
1459 | struct uprobe_task *utask; |
1460 | #endif |
1461 | #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) |
1462 | unsigned int sequential_io; |
1463 | unsigned int sequential_io_avg; |
1464 | #endif |
1465 | struct kmap_ctrl kmap_ctrl; |
1466 | #ifdef CONFIG_DEBUG_ATOMIC_SLEEP |
1467 | unsigned long task_state_change; |
1468 | # ifdef CONFIG_PREEMPT_RT |
1469 | unsigned long saved_state_change; |
1470 | # endif |
1471 | #endif |
1472 | struct rcu_head rcu; |
1473 | refcount_t rcu_users; |
1474 | int pagefault_disabled; |
1475 | #ifdef CONFIG_MMU |
1476 | struct task_struct *oom_reaper_list; |
1477 | struct timer_list oom_reaper_timer; |
1478 | #endif |
1479 | #ifdef CONFIG_VMAP_STACK |
1480 | struct vm_struct *stack_vm_area; |
1481 | #endif |
1482 | #ifdef CONFIG_THREAD_INFO_IN_TASK |
1483 | /* A live task holds one reference: */ |
1484 | refcount_t stack_refcount; |
1485 | #endif |
1486 | #ifdef CONFIG_LIVEPATCH |
1487 | int patch_state; |
1488 | #endif |
1489 | #ifdef CONFIG_SECURITY |
1490 | /* Used by LSM modules for access restriction: */ |
1491 | void *security; |
1492 | #endif |
1493 | #ifdef CONFIG_BPF_SYSCALL |
1494 | /* Used by BPF task local storage */ |
1495 | struct bpf_local_storage __rcu *bpf_storage; |
1496 | /* Used for BPF run context */ |
1497 | struct bpf_run_ctx *bpf_ctx; |
1498 | #endif |
1499 | |
1500 | #ifdef CONFIG_GCC_PLUGIN_STACKLEAK |
1501 | unsigned long lowest_stack; |
1502 | unsigned long prev_lowest_stack; |
1503 | #endif |
1504 | |
1505 | #ifdef CONFIG_X86_MCE |
1506 | void __user *mce_vaddr; |
1507 | __u64 mce_kflags; |
1508 | u64 mce_addr; |
1509 | __u64 mce_ripv : 1, |
1510 | mce_whole_page : 1, |
1511 | __mce_reserved : 62; |
1512 | struct callback_head mce_kill_me; |
1513 | int mce_count; |
1514 | #endif |
1515 | |
1516 | #ifdef CONFIG_KRETPROBES |
1517 | struct llist_head kretprobe_instances; |
1518 | #endif |
1519 | #ifdef CONFIG_RETHOOK |
1520 | struct llist_head rethooks; |
1521 | #endif |
1522 | |
1523 | #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH |
1524 | /* |
1525 | * If L1D flush is supported on mm context switch |
1526 | * then we use this callback head to queue kill work |
1527 | * to kill tasks that are not running on SMT disabled |
1528 | * cores |
1529 | */ |
1530 | struct callback_head l1d_flush_kill; |
1531 | #endif |
1532 | |
1533 | #ifdef CONFIG_RV |
1534 | /* |
1535 | * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS. |
1536 | * If we find justification for more monitors, we can think |
1537 | * about adding more or developing a dynamic method. So far, |
1538 | * none of these are justified. |
1539 | */ |
1540 | union rv_task_monitor rv[RV_PER_TASK_MONITORS]; |
1541 | #endif |
1542 | |
1543 | #ifdef CONFIG_USER_EVENTS |
1544 | struct user_event_mm *user_event_mm; |
1545 | #endif |
1546 | |
1547 | /* |
1548 | * New fields for task_struct should be added above here, so that |
1549 | * they are included in the randomized portion of task_struct. |
1550 | */ |
1551 | randomized_struct_fields_end |
1552 | |
1553 | /* CPU-specific state of this task: */ |
1554 | struct thread_struct thread; |
1555 | |
1556 | /* |
1557 | * WARNING: on x86, 'thread_struct' contains a variable-sized |
1558 | * structure. It *MUST* be at the end of 'task_struct'. |
1559 | * |
1560 | * Do not put anything below here! |
1561 | */ |
1562 | }; |
1563 | |
1564 | static inline struct pid *task_pid(struct task_struct *task) |
1565 | { |
1566 | return task->thread_pid; |
1567 | } |
1568 | |
1569 | /* |
1570 | * the helpers to get the task's different pids as they are seen |
1571 | * from various namespaces |
1572 | * |
1573 | * task_xid_nr() : global id, i.e. the id seen from the init namespace; |
1574 | * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of |
1575 | * current. |
1576 | * task_xid_nr_ns() : id seen from the ns specified; |
1577 | * |
1578 | * see also pid_nr() etc in include/linux/pid.h |
1579 | */ |
1580 | pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns); |
1581 | |
1582 | static inline pid_t task_pid_nr(struct task_struct *tsk) |
1583 | { |
1584 | return tsk->pid; |
1585 | } |
1586 | |
1587 | static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) |
1588 | { |
1589 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_PID, ns); |
1590 | } |
1591 | |
1592 | static inline pid_t task_pid_vnr(struct task_struct *tsk) |
1593 | { |
1594 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_PID, NULL); |
1595 | } |
1596 | |
1597 | |
1598 | static inline pid_t task_tgid_nr(struct task_struct *tsk) |
1599 | { |
1600 | return tsk->tgid; |
1601 | } |
1602 | |
1603 | /** |
1604 | * pid_alive - check that a task structure is not stale |
1605 | * @p: Task structure to be checked. |
1606 | * |
1607 | * Test if a process is not yet dead (at most zombie state) |
1608 | * If pid_alive fails, then pointers within the task structure |
1609 | * can be stale and must not be dereferenced. |
1610 | * |
1611 | * Return: 1 if the process is alive. 0 otherwise. |
1612 | */ |
1613 | static inline int pid_alive(const struct task_struct *p) |
1614 | { |
1615 | return p->thread_pid != NULL; |
1616 | } |
1617 | |
1618 | static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) |
1619 | { |
1620 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_PGID, ns); |
1621 | } |
1622 | |
1623 | static inline pid_t task_pgrp_vnr(struct task_struct *tsk) |
1624 | { |
1625 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_PGID, NULL); |
1626 | } |
1627 | |
1628 | |
1629 | static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) |
1630 | { |
1631 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_SID, ns); |
1632 | } |
1633 | |
1634 | static inline pid_t task_session_vnr(struct task_struct *tsk) |
1635 | { |
1636 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_SID, NULL); |
1637 | } |
1638 | |
1639 | static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) |
1640 | { |
1641 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_TGID, ns); |
1642 | } |
1643 | |
1644 | static inline pid_t task_tgid_vnr(struct task_struct *tsk) |
1645 | { |
1646 | return __task_pid_nr_ns(task: tsk, type: PIDTYPE_TGID, NULL); |
1647 | } |
1648 | |
1649 | static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) |
1650 | { |
1651 | pid_t pid = 0; |
1652 | |
1653 | rcu_read_lock(); |
1654 | if (pid_alive(p: tsk)) |
1655 | pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); |
1656 | rcu_read_unlock(); |
1657 | |
1658 | return pid; |
1659 | } |
1660 | |
1661 | static inline pid_t task_ppid_nr(const struct task_struct *tsk) |
1662 | { |
1663 | return task_ppid_nr_ns(tsk, ns: &init_pid_ns); |
1664 | } |
1665 | |
1666 | /* Obsolete, do not use: */ |
1667 | static inline pid_t task_pgrp_nr(struct task_struct *tsk) |
1668 | { |
1669 | return task_pgrp_nr_ns(tsk, ns: &init_pid_ns); |
1670 | } |
1671 | |
1672 | #define TASK_REPORT_IDLE (TASK_REPORT + 1) |
1673 | #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) |
1674 | |
1675 | static inline unsigned int __task_state_index(unsigned int tsk_state, |
1676 | unsigned int tsk_exit_state) |
1677 | { |
1678 | unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT; |
1679 | |
1680 | BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); |
1681 | |
1682 | if ((tsk_state & TASK_IDLE) == TASK_IDLE) |
1683 | state = TASK_REPORT_IDLE; |
1684 | |
1685 | /* |
1686 | * We're lying here, but rather than expose a completely new task state |
1687 | * to userspace, we can make this appear as if the task has gone through |
1688 | * a regular rt_mutex_lock() call. |
1689 | */ |
1690 | if (tsk_state & TASK_RTLOCK_WAIT) |
1691 | state = TASK_UNINTERRUPTIBLE; |
1692 | |
1693 | return fls(x: state); |
1694 | } |
1695 | |
1696 | static inline unsigned int task_state_index(struct task_struct *tsk) |
1697 | { |
1698 | return __task_state_index(READ_ONCE(tsk->__state), tsk_exit_state: tsk->exit_state); |
1699 | } |
1700 | |
1701 | static inline char task_index_to_char(unsigned int state) |
1702 | { |
1703 | static const char state_char[] = "RSDTtXZPI" ; |
1704 | |
1705 | BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1); |
1706 | |
1707 | return state_char[state]; |
1708 | } |
1709 | |
1710 | static inline char task_state_to_char(struct task_struct *tsk) |
1711 | { |
1712 | return task_index_to_char(state: task_state_index(tsk)); |
1713 | } |
1714 | |
1715 | /** |
1716 | * is_global_init - check if a task structure is init. Since init |
1717 | * is free to have sub-threads we need to check tgid. |
1718 | * @tsk: Task structure to be checked. |
1719 | * |
1720 | * Check if a task structure is the first user space task the kernel created. |
1721 | * |
1722 | * Return: 1 if the task structure is init. 0 otherwise. |
1723 | */ |
1724 | static inline int is_global_init(struct task_struct *tsk) |
1725 | { |
1726 | return task_tgid_nr(tsk) == 1; |
1727 | } |
1728 | |
1729 | extern struct pid *cad_pid; |
1730 | |
1731 | /* |
1732 | * Per process flags |
1733 | */ |
1734 | #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ |
1735 | #define PF_IDLE 0x00000002 /* I am an IDLE thread */ |
1736 | #define PF_EXITING 0x00000004 /* Getting shut down */ |
1737 | #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */ |
1738 | #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ |
1739 | #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ |
1740 | #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ |
1741 | #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ |
1742 | #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ |
1743 | #define PF_DUMPCORE 0x00000200 /* Dumped core */ |
1744 | #define PF_SIGNALED 0x00000400 /* Killed by a signal */ |
1745 | #define PF_MEMALLOC 0x00000800 /* Allocating memory */ |
1746 | #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ |
1747 | #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ |
1748 | #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ |
1749 | #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ |
1750 | #define PF__HOLE__00010000 0x00010000 |
1751 | #define PF_KSWAPD 0x00020000 /* I am kswapd */ |
1752 | #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */ |
1753 | #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */ |
1754 | #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, |
1755 | * I am cleaning dirty pages from some other bdi. */ |
1756 | #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ |
1757 | #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ |
1758 | #define PF__HOLE__00800000 0x00800000 |
1759 | #define PF__HOLE__01000000 0x01000000 |
1760 | #define PF__HOLE__02000000 0x02000000 |
1761 | #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ |
1762 | #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ |
1763 | #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */ |
1764 | #define PF__HOLE__20000000 0x20000000 |
1765 | #define PF__HOLE__40000000 0x40000000 |
1766 | #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ |
1767 | |
1768 | /* |
1769 | * Only the _current_ task can read/write to tsk->flags, but other |
1770 | * tasks can access tsk->flags in readonly mode for example |
1771 | * with tsk_used_math (like during threaded core dumping). |
1772 | * There is however an exception to this rule during ptrace |
1773 | * or during fork: the ptracer task is allowed to write to the |
1774 | * child->flags of its traced child (same goes for fork, the parent |
1775 | * can write to the child->flags), because we're guaranteed the |
1776 | * child is not running and in turn not changing child->flags |
1777 | * at the same time the parent does it. |
1778 | */ |
1779 | #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) |
1780 | #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) |
1781 | #define clear_used_math() clear_stopped_child_used_math(current) |
1782 | #define set_used_math() set_stopped_child_used_math(current) |
1783 | |
1784 | #define conditional_stopped_child_used_math(condition, child) \ |
1785 | do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) |
1786 | |
1787 | #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) |
1788 | |
1789 | #define copy_to_stopped_child_used_math(child) \ |
1790 | do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) |
1791 | |
1792 | /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ |
1793 | #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) |
1794 | #define used_math() tsk_used_math(current) |
1795 | |
1796 | static __always_inline bool is_percpu_thread(void) |
1797 | { |
1798 | #ifdef CONFIG_SMP |
1799 | return (current->flags & PF_NO_SETAFFINITY) && |
1800 | (current->nr_cpus_allowed == 1); |
1801 | #else |
1802 | return true; |
1803 | #endif |
1804 | } |
1805 | |
1806 | /* Per-process atomic flags. */ |
1807 | #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ |
1808 | #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ |
1809 | #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ |
1810 | #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ |
1811 | #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ |
1812 | #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ |
1813 | #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ |
1814 | #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ |
1815 | |
1816 | #define TASK_PFA_TEST(name, func) \ |
1817 | static inline bool task_##func(struct task_struct *p) \ |
1818 | { return test_bit(PFA_##name, &p->atomic_flags); } |
1819 | |
1820 | #define TASK_PFA_SET(name, func) \ |
1821 | static inline void task_set_##func(struct task_struct *p) \ |
1822 | { set_bit(PFA_##name, &p->atomic_flags); } |
1823 | |
1824 | #define TASK_PFA_CLEAR(name, func) \ |
1825 | static inline void task_clear_##func(struct task_struct *p) \ |
1826 | { clear_bit(PFA_##name, &p->atomic_flags); } |
1827 | |
1828 | TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) |
1829 | TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) |
1830 | |
1831 | TASK_PFA_TEST(SPREAD_PAGE, spread_page) |
1832 | TASK_PFA_SET(SPREAD_PAGE, spread_page) |
1833 | TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) |
1834 | |
1835 | TASK_PFA_TEST(SPREAD_SLAB, spread_slab) |
1836 | TASK_PFA_SET(SPREAD_SLAB, spread_slab) |
1837 | TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) |
1838 | |
1839 | TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) |
1840 | TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) |
1841 | TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) |
1842 | |
1843 | TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) |
1844 | TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) |
1845 | TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) |
1846 | |
1847 | TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) |
1848 | TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) |
1849 | |
1850 | TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) |
1851 | TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) |
1852 | TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) |
1853 | |
1854 | TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) |
1855 | TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) |
1856 | |
1857 | static inline void |
1858 | current_restore_flags(unsigned long orig_flags, unsigned long flags) |
1859 | { |
1860 | current->flags &= ~flags; |
1861 | current->flags |= orig_flags & flags; |
1862 | } |
1863 | |
1864 | extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); |
1865 | extern int task_can_attach(struct task_struct *p); |
1866 | extern int dl_bw_alloc(int cpu, u64 dl_bw); |
1867 | extern void dl_bw_free(int cpu, u64 dl_bw); |
1868 | #ifdef CONFIG_SMP |
1869 | |
1870 | /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */ |
1871 | extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); |
1872 | |
1873 | /** |
1874 | * set_cpus_allowed_ptr - set CPU affinity mask of a task |
1875 | * @p: the task |
1876 | * @new_mask: CPU affinity mask |
1877 | * |
1878 | * Return: zero if successful, or a negative error code |
1879 | */ |
1880 | extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); |
1881 | extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); |
1882 | extern void release_user_cpus_ptr(struct task_struct *p); |
1883 | extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask); |
1884 | extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); |
1885 | extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); |
1886 | #else |
1887 | static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) |
1888 | { |
1889 | } |
1890 | static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) |
1891 | { |
1892 | if (!cpumask_test_cpu(0, new_mask)) |
1893 | return -EINVAL; |
1894 | return 0; |
1895 | } |
1896 | static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node) |
1897 | { |
1898 | if (src->user_cpus_ptr) |
1899 | return -EINVAL; |
1900 | return 0; |
1901 | } |
1902 | static inline void release_user_cpus_ptr(struct task_struct *p) |
1903 | { |
1904 | WARN_ON(p->user_cpus_ptr); |
1905 | } |
1906 | |
1907 | static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask) |
1908 | { |
1909 | return 0; |
1910 | } |
1911 | #endif |
1912 | |
1913 | extern int yield_to(struct task_struct *p, bool preempt); |
1914 | extern void set_user_nice(struct task_struct *p, long nice); |
1915 | extern int task_prio(const struct task_struct *p); |
1916 | |
1917 | /** |
1918 | * task_nice - return the nice value of a given task. |
1919 | * @p: the task in question. |
1920 | * |
1921 | * Return: The nice value [ -20 ... 0 ... 19 ]. |
1922 | */ |
1923 | static inline int task_nice(const struct task_struct *p) |
1924 | { |
1925 | return PRIO_TO_NICE((p)->static_prio); |
1926 | } |
1927 | |
1928 | extern int can_nice(const struct task_struct *p, const int nice); |
1929 | extern int task_curr(const struct task_struct *p); |
1930 | extern int idle_cpu(int cpu); |
1931 | extern int available_idle_cpu(int cpu); |
1932 | extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); |
1933 | extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); |
1934 | extern void sched_set_fifo(struct task_struct *p); |
1935 | extern void sched_set_fifo_low(struct task_struct *p); |
1936 | extern void sched_set_normal(struct task_struct *p, int nice); |
1937 | extern int sched_setattr(struct task_struct *, const struct sched_attr *); |
1938 | extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); |
1939 | extern struct task_struct *idle_task(int cpu); |
1940 | |
1941 | /** |
1942 | * is_idle_task - is the specified task an idle task? |
1943 | * @p: the task in question. |
1944 | * |
1945 | * Return: 1 if @p is an idle task. 0 otherwise. |
1946 | */ |
1947 | static __always_inline bool is_idle_task(const struct task_struct *p) |
1948 | { |
1949 | return !!(p->flags & PF_IDLE); |
1950 | } |
1951 | |
1952 | extern struct task_struct *curr_task(int cpu); |
1953 | extern void ia64_set_curr_task(int cpu, struct task_struct *p); |
1954 | |
1955 | void yield(void); |
1956 | |
1957 | union thread_union { |
1958 | #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK |
1959 | struct task_struct task; |
1960 | #endif |
1961 | #ifndef CONFIG_THREAD_INFO_IN_TASK |
1962 | struct thread_info thread_info; |
1963 | #endif |
1964 | unsigned long stack[THREAD_SIZE/sizeof(long)]; |
1965 | }; |
1966 | |
1967 | #ifndef CONFIG_THREAD_INFO_IN_TASK |
1968 | extern struct thread_info init_thread_info; |
1969 | #endif |
1970 | |
1971 | extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; |
1972 | |
1973 | #ifdef CONFIG_THREAD_INFO_IN_TASK |
1974 | # define task_thread_info(task) (&(task)->thread_info) |
1975 | #elif !defined(__HAVE_THREAD_FUNCTIONS) |
1976 | # define task_thread_info(task) ((struct thread_info *)(task)->stack) |
1977 | #endif |
1978 | |
1979 | /* |
1980 | * find a task by one of its numerical ids |
1981 | * |
1982 | * find_task_by_pid_ns(): |
1983 | * finds a task by its pid in the specified namespace |
1984 | * find_task_by_vpid(): |
1985 | * finds a task by its virtual pid |
1986 | * |
1987 | * see also find_vpid() etc in include/linux/pid.h |
1988 | */ |
1989 | |
1990 | extern struct task_struct *find_task_by_vpid(pid_t nr); |
1991 | extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); |
1992 | |
1993 | /* |
1994 | * find a task by its virtual pid and get the task struct |
1995 | */ |
1996 | extern struct task_struct *find_get_task_by_vpid(pid_t nr); |
1997 | |
1998 | extern int wake_up_state(struct task_struct *tsk, unsigned int state); |
1999 | extern int wake_up_process(struct task_struct *tsk); |
2000 | extern void wake_up_new_task(struct task_struct *tsk); |
2001 | |
2002 | #ifdef CONFIG_SMP |
2003 | extern void kick_process(struct task_struct *tsk); |
2004 | #else |
2005 | static inline void kick_process(struct task_struct *tsk) { } |
2006 | #endif |
2007 | |
2008 | extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); |
2009 | |
2010 | static inline void set_task_comm(struct task_struct *tsk, const char *from) |
2011 | { |
2012 | __set_task_comm(tsk, from, exec: false); |
2013 | } |
2014 | |
2015 | extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk); |
2016 | #define get_task_comm(buf, tsk) ({ \ |
2017 | BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \ |
2018 | __get_task_comm(buf, sizeof(buf), tsk); \ |
2019 | }) |
2020 | |
2021 | #ifdef CONFIG_SMP |
2022 | static __always_inline void scheduler_ipi(void) |
2023 | { |
2024 | /* |
2025 | * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting |
2026 | * TIF_NEED_RESCHED remotely (for the first time) will also send |
2027 | * this IPI. |
2028 | */ |
2029 | preempt_fold_need_resched(); |
2030 | } |
2031 | #else |
2032 | static inline void scheduler_ipi(void) { } |
2033 | #endif |
2034 | |
2035 | extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); |
2036 | |
2037 | /* |
2038 | * Set thread flags in other task's structures. |
2039 | * See asm/thread_info.h for TIF_xxxx flags available: |
2040 | */ |
2041 | static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) |
2042 | { |
2043 | set_ti_thread_flag(task_thread_info(tsk), flag); |
2044 | } |
2045 | |
2046 | static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) |
2047 | { |
2048 | clear_ti_thread_flag(task_thread_info(tsk), flag); |
2049 | } |
2050 | |
2051 | static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, |
2052 | bool value) |
2053 | { |
2054 | update_ti_thread_flag(task_thread_info(tsk), flag, value); |
2055 | } |
2056 | |
2057 | static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) |
2058 | { |
2059 | return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); |
2060 | } |
2061 | |
2062 | static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) |
2063 | { |
2064 | return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); |
2065 | } |
2066 | |
2067 | static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) |
2068 | { |
2069 | return test_ti_thread_flag(task_thread_info(tsk), flag); |
2070 | } |
2071 | |
2072 | static inline void set_tsk_need_resched(struct task_struct *tsk) |
2073 | { |
2074 | set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); |
2075 | } |
2076 | |
2077 | static inline void clear_tsk_need_resched(struct task_struct *tsk) |
2078 | { |
2079 | clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); |
2080 | } |
2081 | |
2082 | static inline int test_tsk_need_resched(struct task_struct *tsk) |
2083 | { |
2084 | return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); |
2085 | } |
2086 | |
2087 | /* |
2088 | * cond_resched() and cond_resched_lock(): latency reduction via |
2089 | * explicit rescheduling in places that are safe. The return |
2090 | * value indicates whether a reschedule was done in fact. |
2091 | * cond_resched_lock() will drop the spinlock before scheduling, |
2092 | */ |
2093 | #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) |
2094 | extern int __cond_resched(void); |
2095 | |
2096 | #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) |
2097 | |
2098 | void sched_dynamic_klp_enable(void); |
2099 | void sched_dynamic_klp_disable(void); |
2100 | |
2101 | DECLARE_STATIC_CALL(cond_resched, __cond_resched); |
2102 | |
2103 | static __always_inline int _cond_resched(void) |
2104 | { |
2105 | return static_call_mod(cond_resched)(); |
2106 | } |
2107 | |
2108 | #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) |
2109 | |
2110 | extern int dynamic_cond_resched(void); |
2111 | |
2112 | static __always_inline int _cond_resched(void) |
2113 | { |
2114 | return dynamic_cond_resched(); |
2115 | } |
2116 | |
2117 | #else /* !CONFIG_PREEMPTION */ |
2118 | |
2119 | static inline int _cond_resched(void) |
2120 | { |
2121 | klp_sched_try_switch(); |
2122 | return __cond_resched(); |
2123 | } |
2124 | |
2125 | #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */ |
2126 | |
2127 | #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */ |
2128 | |
2129 | static inline int _cond_resched(void) |
2130 | { |
2131 | klp_sched_try_switch(); |
2132 | return 0; |
2133 | } |
2134 | |
2135 | #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */ |
2136 | |
2137 | #define cond_resched() ({ \ |
2138 | __might_resched(__FILE__, __LINE__, 0); \ |
2139 | _cond_resched(); \ |
2140 | }) |
2141 | |
2142 | extern int __cond_resched_lock(spinlock_t *lock); |
2143 | extern int __cond_resched_rwlock_read(rwlock_t *lock); |
2144 | extern int __cond_resched_rwlock_write(rwlock_t *lock); |
2145 | |
2146 | #define MIGHT_RESCHED_RCU_SHIFT 8 |
2147 | #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1) |
2148 | |
2149 | #ifndef CONFIG_PREEMPT_RT |
2150 | /* |
2151 | * Non RT kernels have an elevated preempt count due to the held lock, |
2152 | * but are not allowed to be inside a RCU read side critical section |
2153 | */ |
2154 | # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET |
2155 | #else |
2156 | /* |
2157 | * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in |
2158 | * cond_resched*lock() has to take that into account because it checks for |
2159 | * preempt_count() and rcu_preempt_depth(). |
2160 | */ |
2161 | # define PREEMPT_LOCK_RESCHED_OFFSETS \ |
2162 | (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT)) |
2163 | #endif |
2164 | |
2165 | #define cond_resched_lock(lock) ({ \ |
2166 | __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ |
2167 | __cond_resched_lock(lock); \ |
2168 | }) |
2169 | |
2170 | #define cond_resched_rwlock_read(lock) ({ \ |
2171 | __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ |
2172 | __cond_resched_rwlock_read(lock); \ |
2173 | }) |
2174 | |
2175 | #define cond_resched_rwlock_write(lock) ({ \ |
2176 | __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ |
2177 | __cond_resched_rwlock_write(lock); \ |
2178 | }) |
2179 | |
2180 | static inline void cond_resched_rcu(void) |
2181 | { |
2182 | #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) |
2183 | rcu_read_unlock(); |
2184 | cond_resched(); |
2185 | rcu_read_lock(); |
2186 | #endif |
2187 | } |
2188 | |
2189 | #ifdef CONFIG_PREEMPT_DYNAMIC |
2190 | |
2191 | extern bool preempt_model_none(void); |
2192 | extern bool preempt_model_voluntary(void); |
2193 | extern bool preempt_model_full(void); |
2194 | |
2195 | #else |
2196 | |
2197 | static inline bool preempt_model_none(void) |
2198 | { |
2199 | return IS_ENABLED(CONFIG_PREEMPT_NONE); |
2200 | } |
2201 | static inline bool preempt_model_voluntary(void) |
2202 | { |
2203 | return IS_ENABLED(CONFIG_PREEMPT_VOLUNTARY); |
2204 | } |
2205 | static inline bool preempt_model_full(void) |
2206 | { |
2207 | return IS_ENABLED(CONFIG_PREEMPT); |
2208 | } |
2209 | |
2210 | #endif |
2211 | |
2212 | static inline bool preempt_model_rt(void) |
2213 | { |
2214 | return IS_ENABLED(CONFIG_PREEMPT_RT); |
2215 | } |
2216 | |
2217 | /* |
2218 | * Does the preemption model allow non-cooperative preemption? |
2219 | * |
2220 | * For !CONFIG_PREEMPT_DYNAMIC kernels this is an exact match with |
2221 | * CONFIG_PREEMPTION; for CONFIG_PREEMPT_DYNAMIC this doesn't work as the |
2222 | * kernel is *built* with CONFIG_PREEMPTION=y but may run with e.g. the |
2223 | * PREEMPT_NONE model. |
2224 | */ |
2225 | static inline bool preempt_model_preemptible(void) |
2226 | { |
2227 | return preempt_model_full() || preempt_model_rt(); |
2228 | } |
2229 | |
2230 | /* |
2231 | * Does a critical section need to be broken due to another |
2232 | * task waiting?: (technically does not depend on CONFIG_PREEMPTION, |
2233 | * but a general need for low latency) |
2234 | */ |
2235 | static inline int spin_needbreak(spinlock_t *lock) |
2236 | { |
2237 | #ifdef CONFIG_PREEMPTION |
2238 | return spin_is_contended(lock); |
2239 | #else |
2240 | return 0; |
2241 | #endif |
2242 | } |
2243 | |
2244 | /* |
2245 | * Check if a rwlock is contended. |
2246 | * Returns non-zero if there is another task waiting on the rwlock. |
2247 | * Returns zero if the lock is not contended or the system / underlying |
2248 | * rwlock implementation does not support contention detection. |
2249 | * Technically does not depend on CONFIG_PREEMPTION, but a general need |
2250 | * for low latency. |
2251 | */ |
2252 | static inline int rwlock_needbreak(rwlock_t *lock) |
2253 | { |
2254 | #ifdef CONFIG_PREEMPTION |
2255 | return rwlock_is_contended(lock); |
2256 | #else |
2257 | return 0; |
2258 | #endif |
2259 | } |
2260 | |
2261 | static __always_inline bool need_resched(void) |
2262 | { |
2263 | return unlikely(tif_need_resched()); |
2264 | } |
2265 | |
2266 | /* |
2267 | * Wrappers for p->thread_info->cpu access. No-op on UP. |
2268 | */ |
2269 | #ifdef CONFIG_SMP |
2270 | |
2271 | static inline unsigned int task_cpu(const struct task_struct *p) |
2272 | { |
2273 | return READ_ONCE(task_thread_info(p)->cpu); |
2274 | } |
2275 | |
2276 | extern void set_task_cpu(struct task_struct *p, unsigned int cpu); |
2277 | |
2278 | #else |
2279 | |
2280 | static inline unsigned int task_cpu(const struct task_struct *p) |
2281 | { |
2282 | return 0; |
2283 | } |
2284 | |
2285 | static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) |
2286 | { |
2287 | } |
2288 | |
2289 | #endif /* CONFIG_SMP */ |
2290 | |
2291 | extern bool sched_task_on_rq(struct task_struct *p); |
2292 | extern unsigned long get_wchan(struct task_struct *p); |
2293 | extern struct task_struct *cpu_curr_snapshot(int cpu); |
2294 | |
2295 | /* |
2296 | * In order to reduce various lock holder preemption latencies provide an |
2297 | * interface to see if a vCPU is currently running or not. |
2298 | * |
2299 | * This allows us to terminate optimistic spin loops and block, analogous to |
2300 | * the native optimistic spin heuristic of testing if the lock owner task is |
2301 | * running or not. |
2302 | */ |
2303 | #ifndef vcpu_is_preempted |
2304 | static inline bool vcpu_is_preempted(int cpu) |
2305 | { |
2306 | return false; |
2307 | } |
2308 | #endif |
2309 | |
2310 | extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); |
2311 | extern long sched_getaffinity(pid_t pid, struct cpumask *mask); |
2312 | |
2313 | #ifndef TASK_SIZE_OF |
2314 | #define TASK_SIZE_OF(tsk) TASK_SIZE |
2315 | #endif |
2316 | |
2317 | #ifdef CONFIG_SMP |
2318 | static inline bool owner_on_cpu(struct task_struct *owner) |
2319 | { |
2320 | /* |
2321 | * As lock holder preemption issue, we both skip spinning if |
2322 | * task is not on cpu or its cpu is preempted |
2323 | */ |
2324 | return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(cpu: task_cpu(p: owner)); |
2325 | } |
2326 | |
2327 | /* Returns effective CPU energy utilization, as seen by the scheduler */ |
2328 | unsigned long sched_cpu_util(int cpu); |
2329 | #endif /* CONFIG_SMP */ |
2330 | |
2331 | #ifdef CONFIG_RSEQ |
2332 | |
2333 | /* |
2334 | * Map the event mask on the user-space ABI enum rseq_cs_flags |
2335 | * for direct mask checks. |
2336 | */ |
2337 | enum rseq_event_mask_bits { |
2338 | RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT, |
2339 | RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT, |
2340 | RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT, |
2341 | }; |
2342 | |
2343 | enum rseq_event_mask { |
2344 | RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT), |
2345 | RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT), |
2346 | RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT), |
2347 | }; |
2348 | |
2349 | static inline void rseq_set_notify_resume(struct task_struct *t) |
2350 | { |
2351 | if (t->rseq) |
2352 | set_tsk_thread_flag(tsk: t, TIF_NOTIFY_RESUME); |
2353 | } |
2354 | |
2355 | void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs); |
2356 | |
2357 | static inline void rseq_handle_notify_resume(struct ksignal *ksig, |
2358 | struct pt_regs *regs) |
2359 | { |
2360 | if (current->rseq) |
2361 | __rseq_handle_notify_resume(sig: ksig, regs); |
2362 | } |
2363 | |
2364 | static inline void rseq_signal_deliver(struct ksignal *ksig, |
2365 | struct pt_regs *regs) |
2366 | { |
2367 | preempt_disable(); |
2368 | __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask); |
2369 | preempt_enable(); |
2370 | rseq_handle_notify_resume(ksig, regs); |
2371 | } |
2372 | |
2373 | /* rseq_preempt() requires preemption to be disabled. */ |
2374 | static inline void rseq_preempt(struct task_struct *t) |
2375 | { |
2376 | __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask); |
2377 | rseq_set_notify_resume(t); |
2378 | } |
2379 | |
2380 | /* rseq_migrate() requires preemption to be disabled. */ |
2381 | static inline void rseq_migrate(struct task_struct *t) |
2382 | { |
2383 | __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask); |
2384 | rseq_set_notify_resume(t); |
2385 | } |
2386 | |
2387 | /* |
2388 | * If parent process has a registered restartable sequences area, the |
2389 | * child inherits. Unregister rseq for a clone with CLONE_VM set. |
2390 | */ |
2391 | static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) |
2392 | { |
2393 | if (clone_flags & CLONE_VM) { |
2394 | t->rseq = NULL; |
2395 | t->rseq_len = 0; |
2396 | t->rseq_sig = 0; |
2397 | t->rseq_event_mask = 0; |
2398 | } else { |
2399 | t->rseq = current->rseq; |
2400 | t->rseq_len = current->rseq_len; |
2401 | t->rseq_sig = current->rseq_sig; |
2402 | t->rseq_event_mask = current->rseq_event_mask; |
2403 | } |
2404 | } |
2405 | |
2406 | static inline void rseq_execve(struct task_struct *t) |
2407 | { |
2408 | t->rseq = NULL; |
2409 | t->rseq_len = 0; |
2410 | t->rseq_sig = 0; |
2411 | t->rseq_event_mask = 0; |
2412 | } |
2413 | |
2414 | #else |
2415 | |
2416 | static inline void rseq_set_notify_resume(struct task_struct *t) |
2417 | { |
2418 | } |
2419 | static inline void rseq_handle_notify_resume(struct ksignal *ksig, |
2420 | struct pt_regs *regs) |
2421 | { |
2422 | } |
2423 | static inline void rseq_signal_deliver(struct ksignal *ksig, |
2424 | struct pt_regs *regs) |
2425 | { |
2426 | } |
2427 | static inline void rseq_preempt(struct task_struct *t) |
2428 | { |
2429 | } |
2430 | static inline void rseq_migrate(struct task_struct *t) |
2431 | { |
2432 | } |
2433 | static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) |
2434 | { |
2435 | } |
2436 | static inline void rseq_execve(struct task_struct *t) |
2437 | { |
2438 | } |
2439 | |
2440 | #endif |
2441 | |
2442 | #ifdef CONFIG_DEBUG_RSEQ |
2443 | |
2444 | void rseq_syscall(struct pt_regs *regs); |
2445 | |
2446 | #else |
2447 | |
2448 | static inline void rseq_syscall(struct pt_regs *regs) |
2449 | { |
2450 | } |
2451 | |
2452 | #endif |
2453 | |
2454 | #ifdef CONFIG_SCHED_CORE |
2455 | extern void sched_core_free(struct task_struct *tsk); |
2456 | extern void sched_core_fork(struct task_struct *p); |
2457 | extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, |
2458 | unsigned long uaddr); |
2459 | extern int sched_core_idle_cpu(int cpu); |
2460 | #else |
2461 | static inline void sched_core_free(struct task_struct *tsk) { } |
2462 | static inline void sched_core_fork(struct task_struct *p) { } |
2463 | static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); } |
2464 | #endif |
2465 | |
2466 | extern void sched_set_stop_task(int cpu, struct task_struct *stop); |
2467 | |
2468 | #endif |
2469 | |