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1da177e4
LT
1#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
607ca46e 4#include <uapi/linux/sched.h>
b7b3c76a 5
5c228079
DY
6#include <linux/sched/prio.h>
7
1da177e4 8#include <linux/capability.h>
b69339ba 9#include <linux/mutex.h>
fb00aca4 10#include <linux/plist.h>
77ba809e 11#include <linux/mm_types_task.h>
1da177e4 12#include <asm/ptrace.h>
1da177e4 13
1da177e4 14#include <linux/sem.h>
ab602f79 15#include <linux/shm.h>
1da177e4 16#include <linux/signal.h>
f361bf4a 17#include <linux/signal_types.h>
1da177e4 18#include <linux/pid.h>
1da177e4 19#include <linux/seccomp.h>
05725f7e 20#include <linux/rculist.h>
23f78d4a 21#include <linux/rtmutex.h>
1da177e4 22
a3b6714e 23#include <linux/resource.h>
a3b6714e 24#include <linux/hrtimer.h>
5c9a8750 25#include <linux/kcov.h>
7c3ab738 26#include <linux/task_io_accounting.h>
9745512c 27#include <linux/latencytop.h>
9e2b2dc4 28#include <linux/cred.h>
21caf2fc 29#include <linux/gfp.h>
fd771233 30#include <linux/topology.h>
d4311ff1 31#include <linux/magic.h>
7d7efec3 32#include <linux/cgroup-defs.h>
a3b6714e 33
70b8157e
IM
34#include <asm/current.h>
35
c7af7877
IM
36/* task_struct member predeclarations: */
37struct audit_context;
38struct autogroup;
39struct backing_dev_info;
bddd87c7 40struct bio_list;
73c10101 41struct blk_plug;
c7af7877 42struct cfs_rq;
c4ad8f98 43struct filename;
c7af7877
IM
44struct fs_struct;
45struct futex_pi_state;
46struct io_context;
47struct mempolicy;
89076bc3 48struct nameidata;
c7af7877
IM
49struct nsproxy;
50struct perf_event_context;
51struct pid_namespace;
52struct pipe_inode_info;
53struct rcu_node;
54struct reclaim_state;
55struct robust_list_head;
56struct sched_attr;
57struct sched_param;
43ae34cb 58struct seq_file;
c7af7877
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59struct sighand_struct;
60struct signal_struct;
61struct task_delay_info;
4cf86d77 62struct task_group;
c7af7877
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63struct task_struct;
64struct uts_namespace;
1da177e4 65
4a8342d2
LT
66/*
67 * Task state bitmask. NOTE! These bits are also
68 * encoded in fs/proc/array.c: get_task_state().
69 *
70 * We have two separate sets of flags: task->state
71 * is about runnability, while task->exit_state are
72 * about the task exiting. Confusing, but this way
73 * modifying one set can't modify the other one by
74 * mistake.
75 */
1da177e4
LT
76#define TASK_RUNNING 0
77#define TASK_INTERRUPTIBLE 1
78#define TASK_UNINTERRUPTIBLE 2
f021a3c2
MW
79#define __TASK_STOPPED 4
80#define __TASK_TRACED 8
4a8342d2 81/* in tsk->exit_state */
ad86622b
ON
82#define EXIT_DEAD 16
83#define EXIT_ZOMBIE 32
abd50b39 84#define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
4a8342d2 85/* in tsk->state again */
af927232 86#define TASK_DEAD 64
f021a3c2 87#define TASK_WAKEKILL 128
e9c84311 88#define TASK_WAKING 256
f2530dc7 89#define TASK_PARKED 512
80ed87c8 90#define TASK_NOLOAD 1024
7dc603c9
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91#define TASK_NEW 2048
92#define TASK_STATE_MAX 4096
f021a3c2 93
7dc603c9 94#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPNn"
73342151 95
642fa448 96/* Convenience macros for the sake of set_current_state */
f021a3c2
MW
97#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
98#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
99#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
1da177e4 100
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101#define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
102
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103/* Convenience macros for the sake of wake_up */
104#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
f021a3c2 105#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
92a1f4bc
MW
106
107/* get_task_state() */
108#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
f021a3c2 109 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
74e37200 110 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
92a1f4bc 111
f021a3c2
MW
112#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
113#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
92a1f4bc 114#define task_is_stopped_or_traced(task) \
f021a3c2 115 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
92a1f4bc 116#define task_contributes_to_load(task) \
e3c8ca83 117 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
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118 (task->flags & PF_FROZEN) == 0 && \
119 (task->state & TASK_NOLOAD) == 0)
1da177e4 120
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121#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
122
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123#define __set_current_state(state_value) \
124 do { \
125 current->task_state_change = _THIS_IP_; \
126 current->state = (state_value); \
127 } while (0)
128#define set_current_state(state_value) \
129 do { \
130 current->task_state_change = _THIS_IP_; \
a2250238 131 smp_store_mb(current->state, (state_value)); \
8eb23b9f
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132 } while (0)
133
134#else
498d0c57
AM
135/*
136 * set_current_state() includes a barrier so that the write of current->state
137 * is correctly serialised wrt the caller's subsequent test of whether to
138 * actually sleep:
139 *
a2250238 140 * for (;;) {
498d0c57 141 * set_current_state(TASK_UNINTERRUPTIBLE);
a2250238
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142 * if (!need_sleep)
143 * break;
144 *
145 * schedule();
146 * }
147 * __set_current_state(TASK_RUNNING);
148 *
149 * If the caller does not need such serialisation (because, for instance, the
150 * condition test and condition change and wakeup are under the same lock) then
151 * use __set_current_state().
152 *
153 * The above is typically ordered against the wakeup, which does:
154 *
155 * need_sleep = false;
156 * wake_up_state(p, TASK_UNINTERRUPTIBLE);
157 *
158 * Where wake_up_state() (and all other wakeup primitives) imply enough
159 * barriers to order the store of the variable against wakeup.
160 *
161 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
162 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
163 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
498d0c57 164 *
a2250238 165 * This is obviously fine, since they both store the exact same value.
498d0c57 166 *
a2250238 167 * Also see the comments of try_to_wake_up().
498d0c57 168 */
8eb23b9f 169#define __set_current_state(state_value) \
1da177e4 170 do { current->state = (state_value); } while (0)
8eb23b9f 171#define set_current_state(state_value) \
b92b8b35 172 smp_store_mb(current->state, (state_value))
1da177e4 173
8eb23b9f
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174#endif
175
1da177e4
LT
176/* Task command name length */
177#define TASK_COMM_LEN 16
178
3fa0818b
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179extern cpumask_var_t cpu_isolated_map;
180
89f19f04 181extern int runqueue_is_locked(int cpu);
017730c1 182
1da177e4
LT
183extern void scheduler_tick(void);
184
1da177e4 185#define MAX_SCHEDULE_TIMEOUT LONG_MAX
b3c97528 186extern signed long schedule_timeout(signed long timeout);
64ed93a2 187extern signed long schedule_timeout_interruptible(signed long timeout);
294d5cc2 188extern signed long schedule_timeout_killable(signed long timeout);
64ed93a2 189extern signed long schedule_timeout_uninterruptible(signed long timeout);
69b27baf 190extern signed long schedule_timeout_idle(signed long timeout);
1da177e4 191asmlinkage void schedule(void);
c5491ea7 192extern void schedule_preempt_disabled(void);
1da177e4 193
10ab5643
TH
194extern int __must_check io_schedule_prepare(void);
195extern void io_schedule_finish(int token);
9cff8ade 196extern long io_schedule_timeout(long timeout);
10ab5643 197extern void io_schedule(void);
9cff8ade 198
d37f761d 199/**
9d7fb042 200 * struct prev_cputime - snaphsot of system and user cputime
d37f761d
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201 * @utime: time spent in user mode
202 * @stime: time spent in system mode
9d7fb042 203 * @lock: protects the above two fields
d37f761d 204 *
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205 * Stores previous user/system time values such that we can guarantee
206 * monotonicity.
d37f761d 207 */
9d7fb042
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208struct prev_cputime {
209#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
5613fda9
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210 u64 utime;
211 u64 stime;
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212 raw_spinlock_t lock;
213#endif
d37f761d
FW
214};
215
f06febc9
FM
216/**
217 * struct task_cputime - collected CPU time counts
5613fda9
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218 * @utime: time spent in user mode, in nanoseconds
219 * @stime: time spent in kernel mode, in nanoseconds
f06febc9 220 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
5ce73a4a 221 *
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222 * This structure groups together three kinds of CPU time that are tracked for
223 * threads and thread groups. Most things considering CPU time want to group
224 * these counts together and treat all three of them in parallel.
f06febc9
FM
225 */
226struct task_cputime {
5613fda9
FW
227 u64 utime;
228 u64 stime;
f06febc9
FM
229 unsigned long long sum_exec_runtime;
230};
9d7fb042 231
f06febc9 232/* Alternate field names when used to cache expirations. */
f06febc9 233#define virt_exp utime
9d7fb042 234#define prof_exp stime
f06febc9
FM
235#define sched_exp sum_exec_runtime
236
4714d1d3 237#include <linux/rwsem.h>
1da177e4 238
f6db8347 239#ifdef CONFIG_SCHED_INFO
1da177e4
LT
240struct sched_info {
241 /* cumulative counters */
2d72376b 242 unsigned long pcount; /* # of times run on this cpu */
9c2c4802 243 unsigned long long run_delay; /* time spent waiting on a runqueue */
1da177e4
LT
244
245 /* timestamps */
172ba844
BS
246 unsigned long long last_arrival,/* when we last ran on a cpu */
247 last_queued; /* when we were last queued to run */
1da177e4 248};
f6db8347 249#endif /* CONFIG_SCHED_INFO */
1da177e4 250
6ecdd749
YD
251/*
252 * Integer metrics need fixed point arithmetic, e.g., sched/fair
253 * has a few: load, load_avg, util_avg, freq, and capacity.
254 *
255 * We define a basic fixed point arithmetic range, and then formalize
256 * all these metrics based on that basic range.
257 */
258# define SCHED_FIXEDPOINT_SHIFT 10
259# define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
260
383f2835 261#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
36c8b586 262extern void prefetch_stack(struct task_struct *t);
383f2835
KC
263#else
264static inline void prefetch_stack(struct task_struct *t) { }
265#endif
1da177e4 266
20b8a59f 267struct load_weight {
9dbdb155
PZ
268 unsigned long weight;
269 u32 inv_weight;
20b8a59f
IM
270};
271
9d89c257 272/*
7b595334
YD
273 * The load_avg/util_avg accumulates an infinite geometric series
274 * (see __update_load_avg() in kernel/sched/fair.c).
275 *
276 * [load_avg definition]
277 *
278 * load_avg = runnable% * scale_load_down(load)
279 *
280 * where runnable% is the time ratio that a sched_entity is runnable.
281 * For cfs_rq, it is the aggregated load_avg of all runnable and
9d89c257 282 * blocked sched_entities.
7b595334
YD
283 *
284 * load_avg may also take frequency scaling into account:
285 *
286 * load_avg = runnable% * scale_load_down(load) * freq%
287 *
288 * where freq% is the CPU frequency normalized to the highest frequency.
289 *
290 * [util_avg definition]
291 *
292 * util_avg = running% * SCHED_CAPACITY_SCALE
293 *
294 * where running% is the time ratio that a sched_entity is running on
295 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
296 * and blocked sched_entities.
297 *
298 * util_avg may also factor frequency scaling and CPU capacity scaling:
299 *
300 * util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity%
301 *
302 * where freq% is the same as above, and capacity% is the CPU capacity
303 * normalized to the greatest capacity (due to uarch differences, etc).
304 *
305 * N.B., the above ratios (runnable%, running%, freq%, and capacity%)
306 * themselves are in the range of [0, 1]. To do fixed point arithmetics,
307 * we therefore scale them to as large a range as necessary. This is for
308 * example reflected by util_avg's SCHED_CAPACITY_SCALE.
309 *
310 * [Overflow issue]
311 *
312 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
313 * with the highest load (=88761), always runnable on a single cfs_rq,
314 * and should not overflow as the number already hits PID_MAX_LIMIT.
315 *
316 * For all other cases (including 32-bit kernels), struct load_weight's
317 * weight will overflow first before we do, because:
318 *
319 * Max(load_avg) <= Max(load.weight)
320 *
321 * Then it is the load_weight's responsibility to consider overflow
322 * issues.
9d89c257 323 */
9d85f21c 324struct sched_avg {
9d89c257
YD
325 u64 last_update_time, load_sum;
326 u32 util_sum, period_contrib;
327 unsigned long load_avg, util_avg;
9d85f21c
PT
328};
329
94c18227 330#ifdef CONFIG_SCHEDSTATS
41acab88 331struct sched_statistics {
20b8a59f 332 u64 wait_start;
94c18227 333 u64 wait_max;
6d082592
AV
334 u64 wait_count;
335 u64 wait_sum;
8f0dfc34
AV
336 u64 iowait_count;
337 u64 iowait_sum;
94c18227 338
20b8a59f 339 u64 sleep_start;
20b8a59f 340 u64 sleep_max;
94c18227
IM
341 s64 sum_sleep_runtime;
342
343 u64 block_start;
20b8a59f
IM
344 u64 block_max;
345 u64 exec_max;
eba1ed4b 346 u64 slice_max;
cc367732 347
cc367732
IM
348 u64 nr_migrations_cold;
349 u64 nr_failed_migrations_affine;
350 u64 nr_failed_migrations_running;
351 u64 nr_failed_migrations_hot;
352 u64 nr_forced_migrations;
cc367732
IM
353
354 u64 nr_wakeups;
355 u64 nr_wakeups_sync;
356 u64 nr_wakeups_migrate;
357 u64 nr_wakeups_local;
358 u64 nr_wakeups_remote;
359 u64 nr_wakeups_affine;
360 u64 nr_wakeups_affine_attempts;
361 u64 nr_wakeups_passive;
362 u64 nr_wakeups_idle;
41acab88
LDM
363};
364#endif
365
366struct sched_entity {
367 struct load_weight load; /* for load-balancing */
368 struct rb_node run_node;
369 struct list_head group_node;
370 unsigned int on_rq;
371
372 u64 exec_start;
373 u64 sum_exec_runtime;
374 u64 vruntime;
375 u64 prev_sum_exec_runtime;
376
41acab88
LDM
377 u64 nr_migrations;
378
41acab88
LDM
379#ifdef CONFIG_SCHEDSTATS
380 struct sched_statistics statistics;
94c18227
IM
381#endif
382
20b8a59f 383#ifdef CONFIG_FAIR_GROUP_SCHED
fed14d45 384 int depth;
20b8a59f
IM
385 struct sched_entity *parent;
386 /* rq on which this entity is (to be) queued: */
387 struct cfs_rq *cfs_rq;
388 /* rq "owned" by this entity/group: */
389 struct cfs_rq *my_q;
390#endif
8bd75c77 391
141965c7 392#ifdef CONFIG_SMP
5a107804
JO
393 /*
394 * Per entity load average tracking.
395 *
396 * Put into separate cache line so it does not
397 * collide with read-mostly values above.
398 */
399 struct sched_avg avg ____cacheline_aligned_in_smp;
9d85f21c 400#endif
20b8a59f 401};
70b97a7f 402
fa717060
PZ
403struct sched_rt_entity {
404 struct list_head run_list;
78f2c7db 405 unsigned long timeout;
57d2aa00 406 unsigned long watchdog_stamp;
bee367ed 407 unsigned int time_slice;
ff77e468
PZ
408 unsigned short on_rq;
409 unsigned short on_list;
6f505b16 410
58d6c2d7 411 struct sched_rt_entity *back;
052f1dc7 412#ifdef CONFIG_RT_GROUP_SCHED
6f505b16
PZ
413 struct sched_rt_entity *parent;
414 /* rq on which this entity is (to be) queued: */
415 struct rt_rq *rt_rq;
416 /* rq "owned" by this entity/group: */
417 struct rt_rq *my_q;
418#endif
fa717060
PZ
419};
420
aab03e05
DF
421struct sched_dl_entity {
422 struct rb_node rb_node;
423
424 /*
425 * Original scheduling parameters. Copied here from sched_attr
4027d080 426 * during sched_setattr(), they will remain the same until
427 * the next sched_setattr().
aab03e05
DF
428 */
429 u64 dl_runtime; /* maximum runtime for each instance */
430 u64 dl_deadline; /* relative deadline of each instance */
755378a4 431 u64 dl_period; /* separation of two instances (period) */
332ac17e 432 u64 dl_bw; /* dl_runtime / dl_deadline */
aab03e05
DF
433
434 /*
435 * Actual scheduling parameters. Initialized with the values above,
436 * they are continously updated during task execution. Note that
437 * the remaining runtime could be < 0 in case we are in overrun.
438 */
439 s64 runtime; /* remaining runtime for this instance */
440 u64 deadline; /* absolute deadline for this instance */
441 unsigned int flags; /* specifying the scheduler behaviour */
442
443 /*
444 * Some bool flags:
445 *
446 * @dl_throttled tells if we exhausted the runtime. If so, the
447 * task has to wait for a replenishment to be performed at the
448 * next firing of dl_timer.
449 *
2d3d891d
DF
450 * @dl_boosted tells if we are boosted due to DI. If so we are
451 * outside bandwidth enforcement mechanism (but only until we
5bfd126e
JL
452 * exit the critical section);
453 *
454 * @dl_yielded tells if task gave up the cpu before consuming
455 * all its available runtime during the last job.
aab03e05 456 */
72f9f3fd 457 int dl_throttled, dl_boosted, dl_yielded;
aab03e05
DF
458
459 /*
460 * Bandwidth enforcement timer. Each -deadline task has its
461 * own bandwidth to be enforced, thus we need one timer per task.
462 */
463 struct hrtimer dl_timer;
464};
8bd75c77 465
1d082fd0
PM
466union rcu_special {
467 struct {
8203d6d0
PM
468 u8 blocked;
469 u8 need_qs;
470 u8 exp_need_qs;
471 u8 pad; /* Otherwise the compiler can store garbage here. */
472 } b; /* Bits. */
473 u32 s; /* Set of bits. */
1d082fd0 474};
86848966 475
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476enum perf_event_task_context {
477 perf_invalid_context = -1,
478 perf_hw_context = 0,
89a1e187 479 perf_sw_context,
8dc85d54
PZ
480 perf_nr_task_contexts,
481};
482
eb61baf6
IM
483struct wake_q_node {
484 struct wake_q_node *next;
485};
486
1da177e4 487struct task_struct {
c65eacbe
AL
488#ifdef CONFIG_THREAD_INFO_IN_TASK
489 /*
490 * For reasons of header soup (see current_thread_info()), this
491 * must be the first element of task_struct.
492 */
493 struct thread_info thread_info;
494#endif
1da177e4 495 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
f7e4217b 496 void *stack;
1da177e4 497 atomic_t usage;
97dc32cd
WC
498 unsigned int flags; /* per process flags, defined below */
499 unsigned int ptrace;
1da177e4 500
2dd73a4f 501#ifdef CONFIG_SMP
fa14ff4a 502 struct llist_node wake_entry;
3ca7a440 503 int on_cpu;
c65eacbe
AL
504#ifdef CONFIG_THREAD_INFO_IN_TASK
505 unsigned int cpu; /* current CPU */
506#endif
63b0e9ed 507 unsigned int wakee_flips;
62470419 508 unsigned long wakee_flip_decay_ts;
63b0e9ed 509 struct task_struct *last_wakee;
ac66f547
PZ
510
511 int wake_cpu;
2dd73a4f 512#endif
fd2f4419 513 int on_rq;
50e645a8 514
b29739f9 515 int prio, static_prio, normal_prio;
c7aceaba 516 unsigned int rt_priority;
5522d5d5 517 const struct sched_class *sched_class;
20b8a59f 518 struct sched_entity se;
fa717060 519 struct sched_rt_entity rt;
8323f26c
PZ
520#ifdef CONFIG_CGROUP_SCHED
521 struct task_group *sched_task_group;
522#endif
aab03e05 523 struct sched_dl_entity dl;
1da177e4 524
e107be36
AK
525#ifdef CONFIG_PREEMPT_NOTIFIERS
526 /* list of struct preempt_notifier: */
527 struct hlist_head preempt_notifiers;
528#endif
529
6c5c9341 530#ifdef CONFIG_BLK_DEV_IO_TRACE
2056a782 531 unsigned int btrace_seq;
6c5c9341 532#endif
1da177e4 533
97dc32cd 534 unsigned int policy;
29baa747 535 int nr_cpus_allowed;
1da177e4 536 cpumask_t cpus_allowed;
1da177e4 537
a57eb940 538#ifdef CONFIG_PREEMPT_RCU
e260be67 539 int rcu_read_lock_nesting;
1d082fd0 540 union rcu_special rcu_read_unlock_special;
f41d911f 541 struct list_head rcu_node_entry;
a57eb940 542 struct rcu_node *rcu_blocked_node;
28f6569a 543#endif /* #ifdef CONFIG_PREEMPT_RCU */
8315f422
PM
544#ifdef CONFIG_TASKS_RCU
545 unsigned long rcu_tasks_nvcsw;
546 bool rcu_tasks_holdout;
547 struct list_head rcu_tasks_holdout_list;
176f8f7a 548 int rcu_tasks_idle_cpu;
8315f422 549#endif /* #ifdef CONFIG_TASKS_RCU */
e260be67 550
f6db8347 551#ifdef CONFIG_SCHED_INFO
1da177e4
LT
552 struct sched_info sched_info;
553#endif
554
555 struct list_head tasks;
806c09a7 556#ifdef CONFIG_SMP
917b627d 557 struct plist_node pushable_tasks;
1baca4ce 558 struct rb_node pushable_dl_tasks;
806c09a7 559#endif
1da177e4
LT
560
561 struct mm_struct *mm, *active_mm;
314ff785
IM
562
563 /* Per-thread vma caching: */
564 struct vmacache vmacache;
565
34e55232
KH
566#if defined(SPLIT_RSS_COUNTING)
567 struct task_rss_stat rss_stat;
568#endif
1da177e4 569/* task state */
97dc32cd 570 int exit_state;
1da177e4
LT
571 int exit_code, exit_signal;
572 int pdeath_signal; /* The signal sent when the parent dies */
e7cc4173 573 unsigned long jobctl; /* JOBCTL_*, siglock protected */
9b89f6ba
AE
574
575 /* Used for emulating ABI behavior of previous Linux versions */
97dc32cd 576 unsigned int personality;
9b89f6ba 577
be958bdc 578 /* scheduler bits, serialized by scheduler locks */
ca94c442 579 unsigned sched_reset_on_fork:1;
a8e4f2ea 580 unsigned sched_contributes_to_load:1;
ff303e66 581 unsigned sched_migrated:1;
b7e7ade3 582 unsigned sched_remote_wakeup:1;
be958bdc
PZ
583 unsigned :0; /* force alignment to the next boundary */
584
585 /* unserialized, strictly 'current' */
586 unsigned in_execve:1; /* bit to tell LSMs we're in execve */
587 unsigned in_iowait:1;
7e781418
AL
588#if !defined(TIF_RESTORE_SIGMASK)
589 unsigned restore_sigmask:1;
590#endif
626ebc41
TH
591#ifdef CONFIG_MEMCG
592 unsigned memcg_may_oom:1;
127424c8 593#ifndef CONFIG_SLOB
6f185c29
VD
594 unsigned memcg_kmem_skip_account:1;
595#endif
127424c8 596#endif
ff303e66
PZ
597#ifdef CONFIG_COMPAT_BRK
598 unsigned brk_randomized:1;
599#endif
6f185c29 600
1d4457f9
KC
601 unsigned long atomic_flags; /* Flags needing atomic access. */
602
f56141e3
AL
603 struct restart_block restart_block;
604
1da177e4
LT
605 pid_t pid;
606 pid_t tgid;
0a425405 607
1314562a 608#ifdef CONFIG_CC_STACKPROTECTOR
0a425405
AV
609 /* Canary value for the -fstack-protector gcc feature */
610 unsigned long stack_canary;
1314562a 611#endif
4d1d61a6 612 /*
1da177e4 613 * pointers to (original) parent process, youngest child, younger sibling,
4d1d61a6 614 * older sibling, respectively. (p->father can be replaced with
f470021a 615 * p->real_parent->pid)
1da177e4 616 */
abd63bc3
KC
617 struct task_struct __rcu *real_parent; /* real parent process */
618 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1da177e4 619 /*
f470021a 620 * children/sibling forms the list of my natural children
1da177e4
LT
621 */
622 struct list_head children; /* list of my children */
623 struct list_head sibling; /* linkage in my parent's children list */
624 struct task_struct *group_leader; /* threadgroup leader */
625
f470021a
RM
626 /*
627 * ptraced is the list of tasks this task is using ptrace on.
628 * This includes both natural children and PTRACE_ATTACH targets.
629 * p->ptrace_entry is p's link on the p->parent->ptraced list.
630 */
631 struct list_head ptraced;
632 struct list_head ptrace_entry;
633
1da177e4 634 /* PID/PID hash table linkage. */
92476d7f 635 struct pid_link pids[PIDTYPE_MAX];
47e65328 636 struct list_head thread_group;
0c740d0a 637 struct list_head thread_node;
1da177e4
LT
638
639 struct completion *vfork_done; /* for vfork() */
640 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
641 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
642
5613fda9 643 u64 utime, stime;
40565b5a 644#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
5613fda9 645 u64 utimescaled, stimescaled;
40565b5a 646#endif
16a6d9be 647 u64 gtime;
9d7fb042 648 struct prev_cputime prev_cputime;
6a61671b 649#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
b7ce2277 650 seqcount_t vtime_seqcount;
6a61671b
FW
651 unsigned long long vtime_snap;
652 enum {
7098c1ea
FW
653 /* Task is sleeping or running in a CPU with VTIME inactive */
654 VTIME_INACTIVE = 0,
655 /* Task runs in userspace in a CPU with VTIME active */
6a61671b 656 VTIME_USER,
7098c1ea 657 /* Task runs in kernelspace in a CPU with VTIME active */
6a61671b
FW
658 VTIME_SYS,
659 } vtime_snap_whence;
d99ca3b9 660#endif
d027d45d
FW
661
662#ifdef CONFIG_NO_HZ_FULL
f009a7a7 663 atomic_t tick_dep_mask;
d027d45d 664#endif
1da177e4 665 unsigned long nvcsw, nivcsw; /* context switch counts */
ccbf62d8 666 u64 start_time; /* monotonic time in nsec */
57e0be04 667 u64 real_start_time; /* boot based time in nsec */
1da177e4
LT
668/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
669 unsigned long min_flt, maj_flt;
670
b18b6a9c 671#ifdef CONFIG_POSIX_TIMERS
f06febc9 672 struct task_cputime cputime_expires;
1da177e4 673 struct list_head cpu_timers[3];
b18b6a9c 674#endif
1da177e4
LT
675
676/* process credentials */
64b875f7 677 const struct cred __rcu *ptracer_cred; /* Tracer's credentials at attach */
1b0ba1c9 678 const struct cred __rcu *real_cred; /* objective and real subjective task
3b11a1de 679 * credentials (COW) */
1b0ba1c9 680 const struct cred __rcu *cred; /* effective (overridable) subjective task
3b11a1de 681 * credentials (COW) */
36772092
PBG
682 char comm[TASK_COMM_LEN]; /* executable name excluding path
683 - access with [gs]et_task_comm (which lock
684 it with task_lock())
221af7f8 685 - initialized normally by setup_new_exec */
1da177e4 686/* file system info */
756daf26 687 struct nameidata *nameidata;
3d5b6fcc 688#ifdef CONFIG_SYSVIPC
1da177e4
LT
689/* ipc stuff */
690 struct sysv_sem sysvsem;
ab602f79 691 struct sysv_shm sysvshm;
3d5b6fcc 692#endif
e162b39a 693#ifdef CONFIG_DETECT_HUNG_TASK
82a1fcb9 694/* hung task detection */
82a1fcb9
IM
695 unsigned long last_switch_count;
696#endif
1da177e4
LT
697/* filesystem information */
698 struct fs_struct *fs;
699/* open file information */
700 struct files_struct *files;
1651e14e 701/* namespaces */
ab516013 702 struct nsproxy *nsproxy;
1da177e4
LT
703/* signal handlers */
704 struct signal_struct *signal;
705 struct sighand_struct *sighand;
706
707 sigset_t blocked, real_blocked;
f3de272b 708 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1da177e4
LT
709 struct sigpending pending;
710
711 unsigned long sas_ss_sp;
712 size_t sas_ss_size;
2a742138 713 unsigned sas_ss_flags;
2e01fabe 714
67d12145 715 struct callback_head *task_works;
e73f8959 716
1da177e4 717 struct audit_context *audit_context;
bfef93a5 718#ifdef CONFIG_AUDITSYSCALL
e1760bd5 719 kuid_t loginuid;
4746ec5b 720 unsigned int sessionid;
bfef93a5 721#endif
932ecebb 722 struct seccomp seccomp;
1da177e4
LT
723
724/* Thread group tracking */
725 u32 parent_exec_id;
726 u32 self_exec_id;
58568d2a
MX
727/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
728 * mempolicy */
1da177e4 729 spinlock_t alloc_lock;
1da177e4 730
b29739f9 731 /* Protection of the PI data structures: */
1d615482 732 raw_spinlock_t pi_lock;
b29739f9 733
76751049
PZ
734 struct wake_q_node wake_q;
735
23f78d4a
IM
736#ifdef CONFIG_RT_MUTEXES
737 /* PI waiters blocked on a rt_mutex held by this task */
fb00aca4
PZ
738 struct rb_root pi_waiters;
739 struct rb_node *pi_waiters_leftmost;
23f78d4a
IM
740 /* Deadlock detection and priority inheritance handling */
741 struct rt_mutex_waiter *pi_blocked_on;
23f78d4a
IM
742#endif
743
408894ee
IM
744#ifdef CONFIG_DEBUG_MUTEXES
745 /* mutex deadlock detection */
746 struct mutex_waiter *blocked_on;
747#endif
de30a2b3
IM
748#ifdef CONFIG_TRACE_IRQFLAGS
749 unsigned int irq_events;
de30a2b3 750 unsigned long hardirq_enable_ip;
de30a2b3 751 unsigned long hardirq_disable_ip;
fa1452e8 752 unsigned int hardirq_enable_event;
de30a2b3 753 unsigned int hardirq_disable_event;
fa1452e8
HS
754 int hardirqs_enabled;
755 int hardirq_context;
de30a2b3 756 unsigned long softirq_disable_ip;
de30a2b3 757 unsigned long softirq_enable_ip;
fa1452e8 758 unsigned int softirq_disable_event;
de30a2b3 759 unsigned int softirq_enable_event;
fa1452e8 760 int softirqs_enabled;
de30a2b3
IM
761 int softirq_context;
762#endif
fbb9ce95 763#ifdef CONFIG_LOCKDEP
bdb9441e 764# define MAX_LOCK_DEPTH 48UL
fbb9ce95
IM
765 u64 curr_chain_key;
766 int lockdep_depth;
fbb9ce95 767 unsigned int lockdep_recursion;
c7aceaba 768 struct held_lock held_locks[MAX_LOCK_DEPTH];
cf40bd16 769 gfp_t lockdep_reclaim_gfp;
fbb9ce95 770#endif
c6d30853
AR
771#ifdef CONFIG_UBSAN
772 unsigned int in_ubsan;
773#endif
408894ee 774
1da177e4
LT
775/* journalling filesystem info */
776 void *journal_info;
777
d89d8796 778/* stacked block device info */
bddd87c7 779 struct bio_list *bio_list;
d89d8796 780
73c10101
JA
781#ifdef CONFIG_BLOCK
782/* stack plugging */
783 struct blk_plug *plug;
784#endif
785
1da177e4
LT
786/* VM state */
787 struct reclaim_state *reclaim_state;
788
1da177e4
LT
789 struct backing_dev_info *backing_dev_info;
790
791 struct io_context *io_context;
792
793 unsigned long ptrace_message;
794 siginfo_t *last_siginfo; /* For ptrace use. */
7c3ab738 795 struct task_io_accounting ioac;
8f0ab514 796#if defined(CONFIG_TASK_XACCT)
1da177e4
LT
797 u64 acct_rss_mem1; /* accumulated rss usage */
798 u64 acct_vm_mem1; /* accumulated virtual memory usage */
605dc2b3 799 u64 acct_timexpd; /* stime + utime since last update */
1da177e4
LT
800#endif
801#ifdef CONFIG_CPUSETS
58568d2a 802 nodemask_t mems_allowed; /* Protected by alloc_lock */
cc9a6c87 803 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */
825a46af 804 int cpuset_mem_spread_rotor;
6adef3eb 805 int cpuset_slab_spread_rotor;
1da177e4 806#endif
ddbcc7e8 807#ifdef CONFIG_CGROUPS
817929ec 808 /* Control Group info protected by css_set_lock */
2c392b8c 809 struct css_set __rcu *cgroups;
817929ec
PM
810 /* cg_list protected by css_set_lock and tsk->alloc_lock */
811 struct list_head cg_list;
ddbcc7e8 812#endif
e02737d5
FY
813#ifdef CONFIG_INTEL_RDT_A
814 int closid;
815#endif
42b2dd0a 816#ifdef CONFIG_FUTEX
0771dfef 817 struct robust_list_head __user *robust_list;
34f192c6
IM
818#ifdef CONFIG_COMPAT
819 struct compat_robust_list_head __user *compat_robust_list;
820#endif
c87e2837
IM
821 struct list_head pi_state_list;
822 struct futex_pi_state *pi_state_cache;
c7aceaba 823#endif
cdd6c482 824#ifdef CONFIG_PERF_EVENTS
8dc85d54 825 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
cdd6c482
IM
826 struct mutex perf_event_mutex;
827 struct list_head perf_event_list;
a63eaf34 828#endif
8f47b187
TG
829#ifdef CONFIG_DEBUG_PREEMPT
830 unsigned long preempt_disable_ip;
831#endif
c7aceaba 832#ifdef CONFIG_NUMA
58568d2a 833 struct mempolicy *mempolicy; /* Protected by alloc_lock */
c7aceaba 834 short il_next;
207205a2 835 short pref_node_fork;
42b2dd0a 836#endif
cbee9f88
PZ
837#ifdef CONFIG_NUMA_BALANCING
838 int numa_scan_seq;
cbee9f88 839 unsigned int numa_scan_period;
598f0ec0 840 unsigned int numa_scan_period_max;
de1c9ce6 841 int numa_preferred_nid;
6b9a7460 842 unsigned long numa_migrate_retry;
cbee9f88 843 u64 node_stamp; /* migration stamp */
7e2703e6
RR
844 u64 last_task_numa_placement;
845 u64 last_sum_exec_runtime;
cbee9f88 846 struct callback_head numa_work;
f809ca9a 847
8c8a743c
PZ
848 struct list_head numa_entry;
849 struct numa_group *numa_group;
850
745d6147 851 /*
44dba3d5
IM
852 * numa_faults is an array split into four regions:
853 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
854 * in this precise order.
855 *
856 * faults_memory: Exponential decaying average of faults on a per-node
857 * basis. Scheduling placement decisions are made based on these
858 * counts. The values remain static for the duration of a PTE scan.
859 * faults_cpu: Track the nodes the process was running on when a NUMA
860 * hinting fault was incurred.
861 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
862 * during the current scan window. When the scan completes, the counts
863 * in faults_memory and faults_cpu decay and these values are copied.
745d6147 864 */
44dba3d5 865 unsigned long *numa_faults;
83e1d2cd 866 unsigned long total_numa_faults;
745d6147 867
04bb2f94
RR
868 /*
869 * numa_faults_locality tracks if faults recorded during the last
074c2381
MG
870 * scan window were remote/local or failed to migrate. The task scan
871 * period is adapted based on the locality of the faults with different
872 * weights depending on whether they were shared or private faults
04bb2f94 873 */
074c2381 874 unsigned long numa_faults_locality[3];
04bb2f94 875
b32e86b4 876 unsigned long numa_pages_migrated;
cbee9f88
PZ
877#endif /* CONFIG_NUMA_BALANCING */
878
72b252ae 879 struct tlbflush_unmap_batch tlb_ubc;
72b252ae 880
e56d0903 881 struct rcu_head rcu;
b92ce558
JA
882
883 /*
884 * cache last used pipe for splice
885 */
886 struct pipe_inode_info *splice_pipe;
5640f768
ED
887
888 struct page_frag task_frag;
889
47913d4e
IM
890#ifdef CONFIG_TASK_DELAY_ACCT
891 struct task_delay_info *delays;
f4f154fd 892#endif
47913d4e 893
f4f154fd
AM
894#ifdef CONFIG_FAULT_INJECTION
895 int make_it_fail;
ca74e92b 896#endif
9d823e8f
WF
897 /*
898 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
899 * balance_dirty_pages() for some dirty throttling pause
900 */
901 int nr_dirtied;
902 int nr_dirtied_pause;
83712358 903 unsigned long dirty_paused_when; /* start of a write-and-pause period */
9d823e8f 904
9745512c
AV
905#ifdef CONFIG_LATENCYTOP
906 int latency_record_count;
907 struct latency_record latency_record[LT_SAVECOUNT];
908#endif
6976675d
AV
909 /*
910 * time slack values; these are used to round up poll() and
911 * select() etc timeout values. These are in nanoseconds.
912 */
da8b44d5
JS
913 u64 timer_slack_ns;
914 u64 default_timer_slack_ns;
f8d570a4 915
0b24becc
AR
916#ifdef CONFIG_KASAN
917 unsigned int kasan_depth;
918#endif
fb52607a 919#ifdef CONFIG_FUNCTION_GRAPH_TRACER
3ad2f3fb 920 /* Index of current stored address in ret_stack */
f201ae23
FW
921 int curr_ret_stack;
922 /* Stack of return addresses for return function tracing */
923 struct ftrace_ret_stack *ret_stack;
8aef2d28
SR
924 /* time stamp for last schedule */
925 unsigned long long ftrace_timestamp;
f201ae23
FW
926 /*
927 * Number of functions that haven't been traced
928 * because of depth overrun.
929 */
930 atomic_t trace_overrun;
380c4b14
FW
931 /* Pause for the tracing */
932 atomic_t tracing_graph_pause;
f201ae23 933#endif
ea4e2bc4
SR
934#ifdef CONFIG_TRACING
935 /* state flags for use by tracers */
936 unsigned long trace;
b1cff0ad 937 /* bitmask and counter of trace recursion */
261842b7
SR
938 unsigned long trace_recursion;
939#endif /* CONFIG_TRACING */
5c9a8750
DV
940#ifdef CONFIG_KCOV
941 /* Coverage collection mode enabled for this task (0 if disabled). */
942 enum kcov_mode kcov_mode;
943 /* Size of the kcov_area. */
944 unsigned kcov_size;
945 /* Buffer for coverage collection. */
946 void *kcov_area;
947 /* kcov desciptor wired with this task or NULL. */
948 struct kcov *kcov;
949#endif
6f185c29 950#ifdef CONFIG_MEMCG
626ebc41
TH
951 struct mem_cgroup *memcg_in_oom;
952 gfp_t memcg_oom_gfp_mask;
953 int memcg_oom_order;
b23afb93
TH
954
955 /* number of pages to reclaim on returning to userland */
956 unsigned int memcg_nr_pages_over_high;
569b846d 957#endif
0326f5a9
SD
958#ifdef CONFIG_UPROBES
959 struct uprobe_task *utask;
0326f5a9 960#endif
cafe5635
KO
961#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
962 unsigned int sequential_io;
963 unsigned int sequential_io_avg;
964#endif
8eb23b9f
PZ
965#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
966 unsigned long task_state_change;
967#endif
8bcbde54 968 int pagefault_disabled;
03049269 969#ifdef CONFIG_MMU
29c696e1 970 struct task_struct *oom_reaper_list;
03049269 971#endif
ba14a194
AL
972#ifdef CONFIG_VMAP_STACK
973 struct vm_struct *stack_vm_area;
974#endif
68f24b08
AL
975#ifdef CONFIG_THREAD_INFO_IN_TASK
976 /* A live task holds one reference. */
977 atomic_t stack_refcount;
978#endif
0c8c0f03
DH
979/* CPU-specific state of this task */
980 struct thread_struct thread;
981/*
982 * WARNING: on x86, 'thread_struct' contains a variable-sized
983 * structure. It *MUST* be at the end of 'task_struct'.
984 *
985 * Do not put anything below here!
986 */
1da177e4
LT
987};
988
e868171a 989static inline struct pid *task_pid(struct task_struct *task)
22c935f4
EB
990{
991 return task->pids[PIDTYPE_PID].pid;
992}
993
e868171a 994static inline struct pid *task_tgid(struct task_struct *task)
22c935f4
EB
995{
996 return task->group_leader->pids[PIDTYPE_PID].pid;
997}
998
6dda81f4
ON
999/*
1000 * Without tasklist or rcu lock it is not safe to dereference
1001 * the result of task_pgrp/task_session even if task == current,
1002 * we can race with another thread doing sys_setsid/sys_setpgid.
1003 */
e868171a 1004static inline struct pid *task_pgrp(struct task_struct *task)
22c935f4
EB
1005{
1006 return task->group_leader->pids[PIDTYPE_PGID].pid;
1007}
1008
e868171a 1009static inline struct pid *task_session(struct task_struct *task)
22c935f4
EB
1010{
1011 return task->group_leader->pids[PIDTYPE_SID].pid;
1012}
1013
7af57294
PE
1014/*
1015 * the helpers to get the task's different pids as they are seen
1016 * from various namespaces
1017 *
1018 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
44c4e1b2
EB
1019 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1020 * current.
7af57294
PE
1021 * task_xid_nr_ns() : id seen from the ns specified;
1022 *
1023 * set_task_vxid() : assigns a virtual id to a task;
1024 *
7af57294
PE
1025 * see also pid_nr() etc in include/linux/pid.h
1026 */
52ee2dfd
ON
1027pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1028 struct pid_namespace *ns);
7af57294 1029
e868171a 1030static inline pid_t task_pid_nr(struct task_struct *tsk)
7af57294
PE
1031{
1032 return tsk->pid;
1033}
1034
52ee2dfd
ON
1035static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1036 struct pid_namespace *ns)
1037{
1038 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1039}
7af57294
PE
1040
1041static inline pid_t task_pid_vnr(struct task_struct *tsk)
1042{
52ee2dfd 1043 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
7af57294
PE
1044}
1045
1046
e868171a 1047static inline pid_t task_tgid_nr(struct task_struct *tsk)
7af57294
PE
1048{
1049 return tsk->tgid;
1050}
1051
2f2a3a46 1052pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
7af57294
PE
1053
1054static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1055{
1056 return pid_vnr(task_tgid(tsk));
1057}
1058
1059
80e0b6e8 1060static inline int pid_alive(const struct task_struct *p);
ad36d282
RGB
1061static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1062{
1063 pid_t pid = 0;
1064
1065 rcu_read_lock();
1066 if (pid_alive(tsk))
1067 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1068 rcu_read_unlock();
1069
1070 return pid;
1071}
1072
1073static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1074{
1075 return task_ppid_nr_ns(tsk, &init_pid_ns);
1076}
1077
52ee2dfd
ON
1078static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1079 struct pid_namespace *ns)
7af57294 1080{
52ee2dfd 1081 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
7af57294
PE
1082}
1083
7af57294
PE
1084static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1085{
52ee2dfd 1086 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
7af57294
PE
1087}
1088
1089
52ee2dfd
ON
1090static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1091 struct pid_namespace *ns)
7af57294 1092{
52ee2dfd 1093 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
7af57294
PE
1094}
1095
7af57294
PE
1096static inline pid_t task_session_vnr(struct task_struct *tsk)
1097{
52ee2dfd 1098 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
7af57294
PE
1099}
1100
1b0f7ffd
ON
1101/* obsolete, do not use */
1102static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1103{
1104 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1105}
7af57294 1106
1da177e4
LT
1107/**
1108 * pid_alive - check that a task structure is not stale
1109 * @p: Task structure to be checked.
1110 *
1111 * Test if a process is not yet dead (at most zombie state)
1112 * If pid_alive fails, then pointers within the task structure
1113 * can be stale and must not be dereferenced.
e69f6186
YB
1114 *
1115 * Return: 1 if the process is alive. 0 otherwise.
1da177e4 1116 */
ad36d282 1117static inline int pid_alive(const struct task_struct *p)
1da177e4 1118{
92476d7f 1119 return p->pids[PIDTYPE_PID].pid != NULL;
1da177e4
LT
1120}
1121
f400e198 1122/**
570f5241
SS
1123 * is_global_init - check if a task structure is init. Since init
1124 * is free to have sub-threads we need to check tgid.
3260259f
HK
1125 * @tsk: Task structure to be checked.
1126 *
1127 * Check if a task structure is the first user space task the kernel created.
e69f6186
YB
1128 *
1129 * Return: 1 if the task structure is init. 0 otherwise.
b460cbc5 1130 */
e868171a 1131static inline int is_global_init(struct task_struct *tsk)
b461cc03 1132{
570f5241 1133 return task_tgid_nr(tsk) == 1;
b461cc03 1134}
b460cbc5 1135
9ec52099
CLG
1136extern struct pid *cad_pid;
1137
1da177e4
LT
1138/*
1139 * Per process flags
1140 */
c1de45ca 1141#define PF_IDLE 0x00000002 /* I am an IDLE thread */
1da177e4 1142#define PF_EXITING 0x00000004 /* getting shut down */
778e9a9c 1143#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
94886b84 1144#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
21aa9af0 1145#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1da177e4 1146#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
4db96cf0 1147#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
1da177e4
LT
1148#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1149#define PF_DUMPCORE 0x00000200 /* dumped core */
1150#define PF_SIGNALED 0x00000400 /* killed by a signal */
1151#define PF_MEMALLOC 0x00000800 /* Allocating memory */
72fa5997 1152#define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */
1da177e4 1153#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
774a1221 1154#define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */
1da177e4
LT
1155#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1156#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1157#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1158#define PF_KSWAPD 0x00040000 /* I am kswapd */
21caf2fc 1159#define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */
1da177e4 1160#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
246bb0b1 1161#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
b31dc66a
JA
1162#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1163#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
14a40ffc 1164#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
4db96cf0 1165#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
61a87122 1166#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
58a69cb4 1167#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
2b44c4db 1168#define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */
1da177e4
LT
1169
1170/*
1171 * Only the _current_ task can read/write to tsk->flags, but other
1172 * tasks can access tsk->flags in readonly mode for example
1173 * with tsk_used_math (like during threaded core dumping).
1174 * There is however an exception to this rule during ptrace
1175 * or during fork: the ptracer task is allowed to write to the
1176 * child->flags of its traced child (same goes for fork, the parent
1177 * can write to the child->flags), because we're guaranteed the
1178 * child is not running and in turn not changing child->flags
1179 * at the same time the parent does it.
1180 */
1181#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1182#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1183#define clear_used_math() clear_stopped_child_used_math(current)
1184#define set_used_math() set_stopped_child_used_math(current)
1185#define conditional_stopped_child_used_math(condition, child) \
1186 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1187#define conditional_used_math(condition) \
1188 conditional_stopped_child_used_math(condition, current)
1189#define copy_to_stopped_child_used_math(child) \
1190 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1191/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1192#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1193#define used_math() tsk_used_math(current)
1194
1d4457f9 1195/* Per-process atomic flags. */
a2b86f77 1196#define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
2ad654bc
ZL
1197#define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1198#define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
77ed2c57 1199#define PFA_LMK_WAITING 3 /* Lowmemorykiller is waiting */
2ad654bc 1200
1d4457f9 1201
e0e5070b
ZL
1202#define TASK_PFA_TEST(name, func) \
1203 static inline bool task_##func(struct task_struct *p) \
1204 { return test_bit(PFA_##name, &p->atomic_flags); }
1205#define TASK_PFA_SET(name, func) \
1206 static inline void task_set_##func(struct task_struct *p) \
1207 { set_bit(PFA_##name, &p->atomic_flags); }
1208#define TASK_PFA_CLEAR(name, func) \
1209 static inline void task_clear_##func(struct task_struct *p) \
1210 { clear_bit(PFA_##name, &p->atomic_flags); }
1211
1212TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1213TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1d4457f9 1214
2ad654bc
ZL
1215TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1216TASK_PFA_SET(SPREAD_PAGE, spread_page)
1217TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1218
1219TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1220TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1221TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1d4457f9 1222
77ed2c57
TH
1223TASK_PFA_TEST(LMK_WAITING, lmk_waiting)
1224TASK_PFA_SET(LMK_WAITING, lmk_waiting)
1225
907aed48
MG
1226static inline void tsk_restore_flags(struct task_struct *task,
1227 unsigned long orig_flags, unsigned long flags)
1228{
1229 task->flags &= ~flags;
1230 task->flags |= orig_flags & flags;
1231}
1232
f82f8042
JL
1233extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
1234 const struct cpumask *trial);
7f51412a
JL
1235extern int task_can_attach(struct task_struct *p,
1236 const struct cpumask *cs_cpus_allowed);
1da177e4 1237#ifdef CONFIG_SMP
1e1b6c51
KM
1238extern void do_set_cpus_allowed(struct task_struct *p,
1239 const struct cpumask *new_mask);
1240
cd8ba7cd 1241extern int set_cpus_allowed_ptr(struct task_struct *p,
96f874e2 1242 const struct cpumask *new_mask);
1da177e4 1243#else
1e1b6c51
KM
1244static inline void do_set_cpus_allowed(struct task_struct *p,
1245 const struct cpumask *new_mask)
1246{
1247}
cd8ba7cd 1248static inline int set_cpus_allowed_ptr(struct task_struct *p,
96f874e2 1249 const struct cpumask *new_mask)
1da177e4 1250{
96f874e2 1251 if (!cpumask_test_cpu(0, new_mask))
1da177e4
LT
1252 return -EINVAL;
1253 return 0;
1254}
1255#endif
e0ad9556 1256
6d0d2878
CB
1257#ifndef cpu_relax_yield
1258#define cpu_relax_yield() cpu_relax()
1259#endif
1260
1da177e4
LT
1261/* sched_exec is called by processes performing an exec */
1262#ifdef CONFIG_SMP
1263extern void sched_exec(void);
1264#else
1265#define sched_exec() {}
1266#endif
1267
fa93384f 1268extern int yield_to(struct task_struct *p, bool preempt);
36c8b586
IM
1269extern void set_user_nice(struct task_struct *p, long nice);
1270extern int task_prio(const struct task_struct *p);
d0ea0268
DY
1271/**
1272 * task_nice - return the nice value of a given task.
1273 * @p: the task in question.
1274 *
1275 * Return: The nice value [ -20 ... 0 ... 19 ].
1276 */
1277static inline int task_nice(const struct task_struct *p)
1278{
1279 return PRIO_TO_NICE((p)->static_prio);
1280}
36c8b586
IM
1281extern int can_nice(const struct task_struct *p, const int nice);
1282extern int task_curr(const struct task_struct *p);
1da177e4 1283extern int idle_cpu(int cpu);
fe7de49f
KM
1284extern int sched_setscheduler(struct task_struct *, int,
1285 const struct sched_param *);
961ccddd 1286extern int sched_setscheduler_nocheck(struct task_struct *, int,
fe7de49f 1287 const struct sched_param *);
d50dde5a
DF
1288extern int sched_setattr(struct task_struct *,
1289 const struct sched_attr *);
36c8b586 1290extern struct task_struct *idle_task(int cpu);
c4f30608
PM
1291/**
1292 * is_idle_task - is the specified task an idle task?
fa757281 1293 * @p: the task in question.
e69f6186
YB
1294 *
1295 * Return: 1 if @p is an idle task. 0 otherwise.
c4f30608 1296 */
7061ca3b 1297static inline bool is_idle_task(const struct task_struct *p)
c4f30608 1298{
c1de45ca 1299 return !!(p->flags & PF_IDLE);
c4f30608 1300}
36c8b586 1301extern struct task_struct *curr_task(int cpu);
a458ae2e 1302extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1da177e4
LT
1303
1304void yield(void);
1305
1da177e4 1306union thread_union {
c65eacbe 1307#ifndef CONFIG_THREAD_INFO_IN_TASK
1da177e4 1308 struct thread_info thread_info;
c65eacbe 1309#endif
1da177e4
LT
1310 unsigned long stack[THREAD_SIZE/sizeof(long)];
1311};
1312
f3ac6067
IM
1313#ifdef CONFIG_THREAD_INFO_IN_TASK
1314static inline struct thread_info *task_thread_info(struct task_struct *task)
1315{
1316 return &task->thread_info;
1317}
1318#elif !defined(__HAVE_THREAD_FUNCTIONS)
1319# define task_thread_info(task) ((struct thread_info *)(task)->stack)
1320#endif
1321
198fe21b
PE
1322extern struct pid_namespace init_pid_ns;
1323
1324/*
1325 * find a task by one of its numerical ids
1326 *
198fe21b
PE
1327 * find_task_by_pid_ns():
1328 * finds a task by its pid in the specified namespace
228ebcbe
PE
1329 * find_task_by_vpid():
1330 * finds a task by its virtual pid
198fe21b 1331 *
e49859e7 1332 * see also find_vpid() etc in include/linux/pid.h
198fe21b
PE
1333 */
1334
228ebcbe
PE
1335extern struct task_struct *find_task_by_vpid(pid_t nr);
1336extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1337 struct pid_namespace *ns);
198fe21b 1338
b3c97528
HH
1339extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1340extern int wake_up_process(struct task_struct *tsk);
3e51e3ed 1341extern void wake_up_new_task(struct task_struct *tsk);
1da177e4
LT
1342#ifdef CONFIG_SMP
1343 extern void kick_process(struct task_struct *tsk);
1344#else
1345 static inline void kick_process(struct task_struct *tsk) { }
1346#endif
1da177e4 1347
82b89778
AH
1348extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1349static inline void set_task_comm(struct task_struct *tsk, const char *from)
1350{
1351 __set_task_comm(tsk, from, false);
1352}
59714d65 1353extern char *get_task_comm(char *to, struct task_struct *tsk);
1da177e4
LT
1354
1355#ifdef CONFIG_SMP
317f3941 1356void scheduler_ipi(void);
85ba2d86 1357extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
1da177e4 1358#else
184748cc 1359static inline void scheduler_ipi(void) { }
85ba2d86
RM
1360static inline unsigned long wait_task_inactive(struct task_struct *p,
1361 long match_state)
1362{
1363 return 1;
1364}
1da177e4
LT
1365#endif
1366
1da177e4
LT
1367/* set thread flags in other task's structures
1368 * - see asm/thread_info.h for TIF_xxxx flags available
1369 */
1370static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1371{
a1261f54 1372 set_ti_thread_flag(task_thread_info(tsk), flag);
1da177e4
LT
1373}
1374
1375static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1376{
a1261f54 1377 clear_ti_thread_flag(task_thread_info(tsk), flag);
1da177e4
LT
1378}
1379
1380static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1381{
a1261f54 1382 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1da177e4
LT
1383}
1384
1385static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1386{
a1261f54 1387 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1da177e4
LT
1388}
1389
1390static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1391{
a1261f54 1392 return test_ti_thread_flag(task_thread_info(tsk), flag);
1da177e4
LT
1393}
1394
1395static inline void set_tsk_need_resched(struct task_struct *tsk)
1396{
1397 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1398}
1399
1400static inline void clear_tsk_need_resched(struct task_struct *tsk)
1401{
1402 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1403}
1404
8ae121ac
GH
1405static inline int test_tsk_need_resched(struct task_struct *tsk)
1406{
1407 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1408}
1409
1da177e4
LT
1410/*
1411 * cond_resched() and cond_resched_lock(): latency reduction via
1412 * explicit rescheduling in places that are safe. The return
1413 * value indicates whether a reschedule was done in fact.
1414 * cond_resched_lock() will drop the spinlock before scheduling,
1415 * cond_resched_softirq() will enable bhs before scheduling.
1416 */
35a773a0 1417#ifndef CONFIG_PREEMPT
c3921ab7 1418extern int _cond_resched(void);
35a773a0
PZ
1419#else
1420static inline int _cond_resched(void) { return 0; }
1421#endif
6f80bd98 1422
613afbf8 1423#define cond_resched() ({ \
3427445a 1424 ___might_sleep(__FILE__, __LINE__, 0); \
613afbf8
FW
1425 _cond_resched(); \
1426})
6f80bd98 1427
613afbf8
FW
1428extern int __cond_resched_lock(spinlock_t *lock);
1429
1430#define cond_resched_lock(lock) ({ \
3427445a 1431 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
613afbf8
FW
1432 __cond_resched_lock(lock); \
1433})
1434
1435extern int __cond_resched_softirq(void);
1436
75e1056f 1437#define cond_resched_softirq() ({ \
3427445a 1438 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
75e1056f 1439 __cond_resched_softirq(); \
613afbf8 1440})
1da177e4 1441
f6f3c437
SH
1442static inline void cond_resched_rcu(void)
1443{
1444#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
1445 rcu_read_unlock();
1446 cond_resched();
1447 rcu_read_lock();
1448#endif
1449}
1450
1da177e4
LT
1451/*
1452 * Does a critical section need to be broken due to another
95c354fe
NP
1453 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
1454 * but a general need for low latency)
1da177e4 1455 */
95c354fe 1456static inline int spin_needbreak(spinlock_t *lock)
1da177e4 1457{
95c354fe
NP
1458#ifdef CONFIG_PREEMPT
1459 return spin_is_contended(lock);
1460#else
1da177e4 1461 return 0;
95c354fe 1462#endif
1da177e4
LT
1463}
1464
75f93fed
PZ
1465static __always_inline bool need_resched(void)
1466{
1467 return unlikely(tif_need_resched());
1468}
1469
1da177e4
LT
1470/*
1471 * Wrappers for p->thread_info->cpu access. No-op on UP.
1472 */
1473#ifdef CONFIG_SMP
1474
1475static inline unsigned int task_cpu(const struct task_struct *p)
1476{
c65eacbe
AL
1477#ifdef CONFIG_THREAD_INFO_IN_TASK
1478 return p->cpu;
1479#else
a1261f54 1480 return task_thread_info(p)->cpu;
c65eacbe 1481#endif
1da177e4
LT
1482}
1483
b32e86b4
IM
1484static inline int task_node(const struct task_struct *p)
1485{
1486 return cpu_to_node(task_cpu(p));
1487}
1488
c65cc870 1489extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
1da177e4
LT
1490
1491#else
1492
1493static inline unsigned int task_cpu(const struct task_struct *p)
1494{
1495 return 0;
1496}
1497
1498static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1499{
1500}
1501
1502#endif /* CONFIG_SMP */
1503
d9345c65
PX
1504/*
1505 * In order to reduce various lock holder preemption latencies provide an
1506 * interface to see if a vCPU is currently running or not.
1507 *
1508 * This allows us to terminate optimistic spin loops and block, analogous to
1509 * the native optimistic spin heuristic of testing if the lock owner task is
1510 * running or not.
1511 */
1512#ifndef vcpu_is_preempted
1513# define vcpu_is_preempted(cpu) false
1514#endif
1515
96f874e2
RR
1516extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
1517extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
5c45bf27 1518
54e99124
DG
1519extern int task_can_switch_user(struct user_struct *up,
1520 struct task_struct *tsk);
1521
82455257
DH
1522#ifndef TASK_SIZE_OF
1523#define TASK_SIZE_OF(tsk) TASK_SIZE
1524#endif
1525
1da177e4 1526#endif