~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/include/linux/sched.h

Version: ~ [ linux-4.15-rc3 ] ~ [ linux-4.14.5 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.68 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.105 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.47 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.87 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.51 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.96 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.27.62 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /* SPDX-License-Identifier: GPL-2.0 */
  2 #ifndef _LINUX_SCHED_H
  3 #define _LINUX_SCHED_H
  4 
  5 /*
  6  * Define 'struct task_struct' and provide the main scheduler
  7  * APIs (schedule(), wakeup variants, etc.)
  8  */
  9 
 10 #include <uapi/linux/sched.h>
 11 
 12 #include <asm/current.h>
 13 
 14 #include <linux/pid.h>
 15 #include <linux/sem.h>
 16 #include <linux/shm.h>
 17 #include <linux/kcov.h>
 18 #include <linux/mutex.h>
 19 #include <linux/plist.h>
 20 #include <linux/hrtimer.h>
 21 #include <linux/seccomp.h>
 22 #include <linux/nodemask.h>
 23 #include <linux/rcupdate.h>
 24 #include <linux/resource.h>
 25 #include <linux/latencytop.h>
 26 #include <linux/sched/prio.h>
 27 #include <linux/signal_types.h>
 28 #include <linux/mm_types_task.h>
 29 #include <linux/task_io_accounting.h>
 30 
 31 /* task_struct member predeclarations (sorted alphabetically): */
 32 struct audit_context;
 33 struct backing_dev_info;
 34 struct bio_list;
 35 struct blk_plug;
 36 struct ccs_domain_info;
 37 struct cfs_rq;
 38 struct fs_struct;
 39 struct futex_pi_state;
 40 struct io_context;
 41 struct mempolicy;
 42 struct nameidata;
 43 struct nsproxy;
 44 struct perf_event_context;
 45 struct pid_namespace;
 46 struct pipe_inode_info;
 47 struct rcu_node;
 48 struct reclaim_state;
 49 struct robust_list_head;
 50 struct sched_attr;
 51 struct sched_param;
 52 struct seq_file;
 53 struct sighand_struct;
 54 struct signal_struct;
 55 struct task_delay_info;
 56 struct task_group;
 57 
 58 /*
 59  * Task state bitmask. NOTE! These bits are also
 60  * encoded in fs/proc/array.c: get_task_state().
 61  *
 62  * We have two separate sets of flags: task->state
 63  * is about runnability, while task->exit_state are
 64  * about the task exiting. Confusing, but this way
 65  * modifying one set can't modify the other one by
 66  * mistake.
 67  */
 68 
 69 /* Used in tsk->state: */
 70 #define TASK_RUNNING                    0x0000
 71 #define TASK_INTERRUPTIBLE              0x0001
 72 #define TASK_UNINTERRUPTIBLE            0x0002
 73 #define __TASK_STOPPED                  0x0004
 74 #define __TASK_TRACED                   0x0008
 75 /* Used in tsk->exit_state: */
 76 #define EXIT_DEAD                       0x0010
 77 #define EXIT_ZOMBIE                     0x0020
 78 #define EXIT_TRACE                      (EXIT_ZOMBIE | EXIT_DEAD)
 79 /* Used in tsk->state again: */
 80 #define TASK_PARKED                     0x0040
 81 #define TASK_DEAD                       0x0080
 82 #define TASK_WAKEKILL                   0x0100
 83 #define TASK_WAKING                     0x0200
 84 #define TASK_NOLOAD                     0x0400
 85 #define TASK_NEW                        0x0800
 86 #define TASK_STATE_MAX                  0x1000
 87 
 88 /* Convenience macros for the sake of set_current_state: */
 89 #define TASK_KILLABLE                   (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
 90 #define TASK_STOPPED                    (TASK_WAKEKILL | __TASK_STOPPED)
 91 #define TASK_TRACED                     (TASK_WAKEKILL | __TASK_TRACED)
 92 
 93 #define TASK_IDLE                       (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
 94 
 95 /* Convenience macros for the sake of wake_up(): */
 96 #define TASK_NORMAL                     (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
 97 #define TASK_ALL                        (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
 98 
 99 /* get_task_state(): */
100 #define TASK_REPORT                     (TASK_RUNNING | TASK_INTERRUPTIBLE | \
101                                          TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
102                                          __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
103                                          TASK_PARKED)
104 
105 #define task_is_traced(task)            ((task->state & __TASK_TRACED) != 0)
106 
107 #define task_is_stopped(task)           ((task->state & __TASK_STOPPED) != 0)
108 
109 #define task_is_stopped_or_traced(task) ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
110 
111 #define task_contributes_to_load(task)  ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
112                                          (task->flags & PF_FROZEN) == 0 && \
113                                          (task->state & TASK_NOLOAD) == 0)
114 
115 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
116 
117 #define __set_current_state(state_value)                        \
118         do {                                                    \
119                 current->task_state_change = _THIS_IP_;         \
120                 current->state = (state_value);                 \
121         } while (0)
122 #define set_current_state(state_value)                          \
123         do {                                                    \
124                 current->task_state_change = _THIS_IP_;         \
125                 smp_store_mb(current->state, (state_value));    \
126         } while (0)
127 
128 #else
129 /*
130  * set_current_state() includes a barrier so that the write of current->state
131  * is correctly serialised wrt the caller's subsequent test of whether to
132  * actually sleep:
133  *
134  *   for (;;) {
135  *      set_current_state(TASK_UNINTERRUPTIBLE);
136  *      if (!need_sleep)
137  *              break;
138  *
139  *      schedule();
140  *   }
141  *   __set_current_state(TASK_RUNNING);
142  *
143  * If the caller does not need such serialisation (because, for instance, the
144  * condition test and condition change and wakeup are under the same lock) then
145  * use __set_current_state().
146  *
147  * The above is typically ordered against the wakeup, which does:
148  *
149  *      need_sleep = false;
150  *      wake_up_state(p, TASK_UNINTERRUPTIBLE);
151  *
152  * Where wake_up_state() (and all other wakeup primitives) imply enough
153  * barriers to order the store of the variable against wakeup.
154  *
155  * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
156  * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
157  * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
158  *
159  * This is obviously fine, since they both store the exact same value.
160  *
161  * Also see the comments of try_to_wake_up().
162  */
163 #define __set_current_state(state_value) do { current->state = (state_value); } while (0)
164 #define set_current_state(state_value)   smp_store_mb(current->state, (state_value))
165 #endif
166 
167 /* Task command name length: */
168 #define TASK_COMM_LEN                   16
169 
170 extern void scheduler_tick(void);
171 
172 #define MAX_SCHEDULE_TIMEOUT            LONG_MAX
173 
174 extern long schedule_timeout(long timeout);
175 extern long schedule_timeout_interruptible(long timeout);
176 extern long schedule_timeout_killable(long timeout);
177 extern long schedule_timeout_uninterruptible(long timeout);
178 extern long schedule_timeout_idle(long timeout);
179 asmlinkage void schedule(void);
180 extern void schedule_preempt_disabled(void);
181 
182 extern int __must_check io_schedule_prepare(void);
183 extern void io_schedule_finish(int token);
184 extern long io_schedule_timeout(long timeout);
185 extern void io_schedule(void);
186 
187 /**
188  * struct prev_cputime - snapshot of system and user cputime
189  * @utime: time spent in user mode
190  * @stime: time spent in system mode
191  * @lock: protects the above two fields
192  *
193  * Stores previous user/system time values such that we can guarantee
194  * monotonicity.
195  */
196 struct prev_cputime {
197 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
198         u64                             utime;
199         u64                             stime;
200         raw_spinlock_t                  lock;
201 #endif
202 };
203 
204 /**
205  * struct task_cputime - collected CPU time counts
206  * @utime:              time spent in user mode, in nanoseconds
207  * @stime:              time spent in kernel mode, in nanoseconds
208  * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
209  *
210  * This structure groups together three kinds of CPU time that are tracked for
211  * threads and thread groups.  Most things considering CPU time want to group
212  * these counts together and treat all three of them in parallel.
213  */
214 struct task_cputime {
215         u64                             utime;
216         u64                             stime;
217         unsigned long long              sum_exec_runtime;
218 };
219 
220 /* Alternate field names when used on cache expirations: */
221 #define virt_exp                        utime
222 #define prof_exp                        stime
223 #define sched_exp                       sum_exec_runtime
224 
225 enum vtime_state {
226         /* Task is sleeping or running in a CPU with VTIME inactive: */
227         VTIME_INACTIVE = 0,
228         /* Task runs in userspace in a CPU with VTIME active: */
229         VTIME_USER,
230         /* Task runs in kernelspace in a CPU with VTIME active: */
231         VTIME_SYS,
232 };
233 
234 struct vtime {
235         seqcount_t              seqcount;
236         unsigned long long      starttime;
237         enum vtime_state        state;
238         u64                     utime;
239         u64                     stime;
240         u64                     gtime;
241 };
242 
243 struct sched_info {
244 #ifdef CONFIG_SCHED_INFO
245         /* Cumulative counters: */
246 
247         /* # of times we have run on this CPU: */
248         unsigned long                   pcount;
249 
250         /* Time spent waiting on a runqueue: */
251         unsigned long long              run_delay;
252 
253         /* Timestamps: */
254 
255         /* When did we last run on a CPU? */
256         unsigned long long              last_arrival;
257 
258         /* When were we last queued to run? */
259         unsigned long long              last_queued;
260 
261 #endif /* CONFIG_SCHED_INFO */
262 };
263 
264 /*
265  * Integer metrics need fixed point arithmetic, e.g., sched/fair
266  * has a few: load, load_avg, util_avg, freq, and capacity.
267  *
268  * We define a basic fixed point arithmetic range, and then formalize
269  * all these metrics based on that basic range.
270  */
271 # define SCHED_FIXEDPOINT_SHIFT         10
272 # define SCHED_FIXEDPOINT_SCALE         (1L << SCHED_FIXEDPOINT_SHIFT)
273 
274 struct load_weight {
275         unsigned long                   weight;
276         u32                             inv_weight;
277 };
278 
279 /*
280  * The load_avg/util_avg accumulates an infinite geometric series
281  * (see __update_load_avg() in kernel/sched/fair.c).
282  *
283  * [load_avg definition]
284  *
285  *   load_avg = runnable% * scale_load_down(load)
286  *
287  * where runnable% is the time ratio that a sched_entity is runnable.
288  * For cfs_rq, it is the aggregated load_avg of all runnable and
289  * blocked sched_entities.
290  *
291  * load_avg may also take frequency scaling into account:
292  *
293  *   load_avg = runnable% * scale_load_down(load) * freq%
294  *
295  * where freq% is the CPU frequency normalized to the highest frequency.
296  *
297  * [util_avg definition]
298  *
299  *   util_avg = running% * SCHED_CAPACITY_SCALE
300  *
301  * where running% is the time ratio that a sched_entity is running on
302  * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
303  * and blocked sched_entities.
304  *
305  * util_avg may also factor frequency scaling and CPU capacity scaling:
306  *
307  *   util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity%
308  *
309  * where freq% is the same as above, and capacity% is the CPU capacity
310  * normalized to the greatest capacity (due to uarch differences, etc).
311  *
312  * N.B., the above ratios (runnable%, running%, freq%, and capacity%)
313  * themselves are in the range of [0, 1]. To do fixed point arithmetics,
314  * we therefore scale them to as large a range as necessary. This is for
315  * example reflected by util_avg's SCHED_CAPACITY_SCALE.
316  *
317  * [Overflow issue]
318  *
319  * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
320  * with the highest load (=88761), always runnable on a single cfs_rq,
321  * and should not overflow as the number already hits PID_MAX_LIMIT.
322  *
323  * For all other cases (including 32-bit kernels), struct load_weight's
324  * weight will overflow first before we do, because:
325  *
326  *    Max(load_avg) <= Max(load.weight)
327  *
328  * Then it is the load_weight's responsibility to consider overflow
329  * issues.
330  */
331 struct sched_avg {
332         u64                             last_update_time;
333         u64                             load_sum;
334         u64                             runnable_load_sum;
335         u32                             util_sum;
336         u32                             period_contrib;
337         unsigned long                   load_avg;
338         unsigned long                   runnable_load_avg;
339         unsigned long                   util_avg;
340 };
341 
342 struct sched_statistics {
343 #ifdef CONFIG_SCHEDSTATS
344         u64                             wait_start;
345         u64                             wait_max;
346         u64                             wait_count;
347         u64                             wait_sum;
348         u64                             iowait_count;
349         u64                             iowait_sum;
350 
351         u64                             sleep_start;
352         u64                             sleep_max;
353         s64                             sum_sleep_runtime;
354 
355         u64                             block_start;
356         u64                             block_max;
357         u64                             exec_max;
358         u64                             slice_max;
359 
360         u64                             nr_migrations_cold;
361         u64                             nr_failed_migrations_affine;
362         u64                             nr_failed_migrations_running;
363         u64                             nr_failed_migrations_hot;
364         u64                             nr_forced_migrations;
365 
366         u64                             nr_wakeups;
367         u64                             nr_wakeups_sync;
368         u64                             nr_wakeups_migrate;
369         u64                             nr_wakeups_local;
370         u64                             nr_wakeups_remote;
371         u64                             nr_wakeups_affine;
372         u64                             nr_wakeups_affine_attempts;
373         u64                             nr_wakeups_passive;
374         u64                             nr_wakeups_idle;
375 #endif
376 };
377 
378 struct sched_entity {
379         /* For load-balancing: */
380         struct load_weight              load;
381         unsigned long                   runnable_weight;
382         struct rb_node                  run_node;
383         struct list_head                group_node;
384         unsigned int                    on_rq;
385 
386         u64                             exec_start;
387         u64                             sum_exec_runtime;
388         u64                             vruntime;
389         u64                             prev_sum_exec_runtime;
390 
391         u64                             nr_migrations;
392 
393         struct sched_statistics         statistics;
394 
395 #ifdef CONFIG_FAIR_GROUP_SCHED
396         int                             depth;
397         struct sched_entity             *parent;
398         /* rq on which this entity is (to be) queued: */
399         struct cfs_rq                   *cfs_rq;
400         /* rq "owned" by this entity/group: */
401         struct cfs_rq                   *my_q;
402 #endif
403 
404 #ifdef CONFIG_SMP
405         /*
406          * Per entity load average tracking.
407          *
408          * Put into separate cache line so it does not
409          * collide with read-mostly values above.
410          */
411         struct sched_avg                avg ____cacheline_aligned_in_smp;
412 #endif
413 };
414 
415 struct sched_rt_entity {
416         struct list_head                run_list;
417         unsigned long                   timeout;
418         unsigned long                   watchdog_stamp;
419         unsigned int                    time_slice;
420         unsigned short                  on_rq;
421         unsigned short                  on_list;
422 
423         struct sched_rt_entity          *back;
424 #ifdef CONFIG_RT_GROUP_SCHED
425         struct sched_rt_entity          *parent;
426         /* rq on which this entity is (to be) queued: */
427         struct rt_rq                    *rt_rq;
428         /* rq "owned" by this entity/group: */
429         struct rt_rq                    *my_q;
430 #endif
431 } __randomize_layout;
432 
433 struct sched_dl_entity {
434         struct rb_node                  rb_node;
435 
436         /*
437          * Original scheduling parameters. Copied here from sched_attr
438          * during sched_setattr(), they will remain the same until
439          * the next sched_setattr().
440          */
441         u64                             dl_runtime;     /* Maximum runtime for each instance    */
442         u64                             dl_deadline;    /* Relative deadline of each instance   */
443         u64                             dl_period;      /* Separation of two instances (period) */
444         u64                             dl_bw;          /* dl_runtime / dl_period               */
445         u64                             dl_density;     /* dl_runtime / dl_deadline             */
446 
447         /*
448          * Actual scheduling parameters. Initialized with the values above,
449          * they are continously updated during task execution. Note that
450          * the remaining runtime could be < 0 in case we are in overrun.
451          */
452         s64                             runtime;        /* Remaining runtime for this instance  */
453         u64                             deadline;       /* Absolute deadline for this instance  */
454         unsigned int                    flags;          /* Specifying the scheduler behaviour   */
455 
456         /*
457          * Some bool flags:
458          *
459          * @dl_throttled tells if we exhausted the runtime. If so, the
460          * task has to wait for a replenishment to be performed at the
461          * next firing of dl_timer.
462          *
463          * @dl_boosted tells if we are boosted due to DI. If so we are
464          * outside bandwidth enforcement mechanism (but only until we
465          * exit the critical section);
466          *
467          * @dl_yielded tells if task gave up the CPU before consuming
468          * all its available runtime during the last job.
469          *
470          * @dl_non_contending tells if the task is inactive while still
471          * contributing to the active utilization. In other words, it
472          * indicates if the inactive timer has been armed and its handler
473          * has not been executed yet. This flag is useful to avoid race
474          * conditions between the inactive timer handler and the wakeup
475          * code.
476          */
477         unsigned int                    dl_throttled      : 1;
478         unsigned int                    dl_boosted        : 1;
479         unsigned int                    dl_yielded        : 1;
480         unsigned int                    dl_non_contending : 1;
481 
482         /*
483          * Bandwidth enforcement timer. Each -deadline task has its
484          * own bandwidth to be enforced, thus we need one timer per task.
485          */
486         struct hrtimer                  dl_timer;
487 
488         /*
489          * Inactive timer, responsible for decreasing the active utilization
490          * at the "0-lag time". When a -deadline task blocks, it contributes
491          * to GRUB's active utilization until the "0-lag time", hence a
492          * timer is needed to decrease the active utilization at the correct
493          * time.
494          */
495         struct hrtimer inactive_timer;
496 };
497 
498 union rcu_special {
499         struct {
500                 u8                      blocked;
501                 u8                      need_qs;
502                 u8                      exp_need_qs;
503 
504                 /* Otherwise the compiler can store garbage here: */
505                 u8                      pad;
506         } b; /* Bits. */
507         u32 s; /* Set of bits. */
508 };
509 
510 enum perf_event_task_context {
511         perf_invalid_context = -1,
512         perf_hw_context = 0,
513         perf_sw_context,
514         perf_nr_task_contexts,
515 };
516 
517 struct wake_q_node {
518         struct wake_q_node *next;
519 };
520 
521 struct task_struct {
522 #ifdef CONFIG_THREAD_INFO_IN_TASK
523         /*
524          * For reasons of header soup (see current_thread_info()), this
525          * must be the first element of task_struct.
526          */
527         struct thread_info              thread_info;
528 #endif
529         /* -1 unrunnable, 0 runnable, >0 stopped: */
530         volatile long                   state;
531 
532         /*
533          * This begins the randomizable portion of task_struct. Only
534          * scheduling-critical items should be added above here.
535          */
536         randomized_struct_fields_start
537 
538         void                            *stack;
539         atomic_t                        usage;
540         /* Per task flags (PF_*), defined further below: */
541         unsigned int                    flags;
542         unsigned int                    ptrace;
543 
544 #ifdef CONFIG_SMP
545         struct llist_node               wake_entry;
546         int                             on_cpu;
547 #ifdef CONFIG_THREAD_INFO_IN_TASK
548         /* Current CPU: */
549         unsigned int                    cpu;
550 #endif
551         unsigned int                    wakee_flips;
552         unsigned long                   wakee_flip_decay_ts;
553         struct task_struct              *last_wakee;
554 
555         int                             wake_cpu;
556 #endif
557         int                             on_rq;
558 
559         int                             prio;
560         int                             static_prio;
561         int                             normal_prio;
562         unsigned int                    rt_priority;
563 
564         const struct sched_class        *sched_class;
565         struct sched_entity             se;
566         struct sched_rt_entity          rt;
567 #ifdef CONFIG_CGROUP_SCHED
568         struct task_group               *sched_task_group;
569 #endif
570         struct sched_dl_entity          dl;
571 
572 #ifdef CONFIG_PREEMPT_NOTIFIERS
573         /* List of struct preempt_notifier: */
574         struct hlist_head               preempt_notifiers;
575 #endif
576 
577 #ifdef CONFIG_BLK_DEV_IO_TRACE
578         unsigned int                    btrace_seq;
579 #endif
580 
581         unsigned int                    policy;
582         int                             nr_cpus_allowed;
583         cpumask_t                       cpus_allowed;
584 
585 #ifdef CONFIG_PREEMPT_RCU
586         int                             rcu_read_lock_nesting;
587         union rcu_special               rcu_read_unlock_special;
588         struct list_head                rcu_node_entry;
589         struct rcu_node                 *rcu_blocked_node;
590 #endif /* #ifdef CONFIG_PREEMPT_RCU */
591 
592 #ifdef CONFIG_TASKS_RCU
593         unsigned long                   rcu_tasks_nvcsw;
594         u8                              rcu_tasks_holdout;
595         u8                              rcu_tasks_idx;
596         int                             rcu_tasks_idle_cpu;
597         struct list_head                rcu_tasks_holdout_list;
598 #endif /* #ifdef CONFIG_TASKS_RCU */
599 
600         struct sched_info               sched_info;
601 
602         struct list_head                tasks;
603 #ifdef CONFIG_SMP
604         struct plist_node               pushable_tasks;
605         struct rb_node                  pushable_dl_tasks;
606 #endif
607 
608         struct mm_struct                *mm;
609         struct mm_struct                *active_mm;
610 
611         /* Per-thread vma caching: */
612         struct vmacache                 vmacache;
613 
614 #ifdef SPLIT_RSS_COUNTING
615         struct task_rss_stat            rss_stat;
616 #endif
617         int                             exit_state;
618         int                             exit_code;
619         int                             exit_signal;
620         /* The signal sent when the parent dies: */
621         int                             pdeath_signal;
622         /* JOBCTL_*, siglock protected: */
623         unsigned long                   jobctl;
624 
625         /* Used for emulating ABI behavior of previous Linux versions: */
626         unsigned int                    personality;
627 
628         /* Scheduler bits, serialized by scheduler locks: */
629         unsigned                        sched_reset_on_fork:1;
630         unsigned                        sched_contributes_to_load:1;
631         unsigned                        sched_migrated:1;
632         unsigned                        sched_remote_wakeup:1;
633         /* Force alignment to the next boundary: */
634         unsigned                        :0;
635 
636         /* Unserialized, strictly 'current' */
637 
638         /* Bit to tell LSMs we're in execve(): */
639         unsigned                        in_execve:1;
640         unsigned                        in_iowait:1;
641 #ifndef TIF_RESTORE_SIGMASK
642         unsigned                        restore_sigmask:1;
643 #endif
644 #ifdef CONFIG_MEMCG
645         unsigned                        memcg_may_oom:1;
646 #ifndef CONFIG_SLOB
647         unsigned                        memcg_kmem_skip_account:1;
648 #endif
649 #endif
650 #ifdef CONFIG_COMPAT_BRK
651         unsigned                        brk_randomized:1;
652 #endif
653 #ifdef CONFIG_CGROUPS
654         /* disallow userland-initiated cgroup migration */
655         unsigned                        no_cgroup_migration:1;
656 #endif
657 
658         unsigned long                   atomic_flags; /* Flags requiring atomic access. */
659 
660         struct restart_block            restart_block;
661 
662         pid_t                           pid;
663         pid_t                           tgid;
664 
665 #ifdef CONFIG_CC_STACKPROTECTOR
666         /* Canary value for the -fstack-protector GCC feature: */
667         unsigned long                   stack_canary;
668 #endif
669         /*
670          * Pointers to the (original) parent process, youngest child, younger sibling,
671          * older sibling, respectively.  (p->father can be replaced with
672          * p->real_parent->pid)
673          */
674 
675         /* Real parent process: */
676         struct task_struct __rcu        *real_parent;
677 
678         /* Recipient of SIGCHLD, wait4() reports: */
679         struct task_struct __rcu        *parent;
680 
681         /*
682          * Children/sibling form the list of natural children:
683          */
684         struct list_head                children;
685         struct list_head                sibling;
686         struct task_struct              *group_leader;
687 
688         /*
689          * 'ptraced' is the list of tasks this task is using ptrace() on.
690          *
691          * This includes both natural children and PTRACE_ATTACH targets.
692          * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
693          */
694         struct list_head                ptraced;
695         struct list_head                ptrace_entry;
696 
697         /* PID/PID hash table linkage. */
698         struct pid_link                 pids[PIDTYPE_MAX];
699         struct list_head                thread_group;
700         struct list_head                thread_node;
701 
702         struct completion               *vfork_done;
703 
704         /* CLONE_CHILD_SETTID: */
705         int __user                      *set_child_tid;
706 
707         /* CLONE_CHILD_CLEARTID: */
708         int __user                      *clear_child_tid;
709 
710         u64                             utime;
711         u64                             stime;
712 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
713         u64                             utimescaled;
714         u64                             stimescaled;
715 #endif
716         u64                             gtime;
717         struct prev_cputime             prev_cputime;
718 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
719         struct vtime                    vtime;
720 #endif
721 
722 #ifdef CONFIG_NO_HZ_FULL
723         atomic_t                        tick_dep_mask;
724 #endif
725         /* Context switch counts: */
726         unsigned long                   nvcsw;
727         unsigned long                   nivcsw;
728 
729         /* Monotonic time in nsecs: */
730         u64                             start_time;
731 
732         /* Boot based time in nsecs: */
733         u64                             real_start_time;
734 
735         /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
736         unsigned long                   min_flt;
737         unsigned long                   maj_flt;
738 
739 #ifdef CONFIG_POSIX_TIMERS
740         struct task_cputime             cputime_expires;
741         struct list_head                cpu_timers[3];
742 #endif
743 
744         /* Process credentials: */
745 
746         /* Tracer's credentials at attach: */
747         const struct cred __rcu         *ptracer_cred;
748 
749         /* Objective and real subjective task credentials (COW): */
750         const struct cred __rcu         *real_cred;
751 
752         /* Effective (overridable) subjective task credentials (COW): */
753         const struct cred __rcu         *cred;
754 
755         /*
756          * executable name, excluding path.
757          *
758          * - normally initialized setup_new_exec()
759          * - access it with [gs]et_task_comm()
760          * - lock it with task_lock()
761          */
762         char                            comm[TASK_COMM_LEN];
763 
764         struct nameidata                *nameidata;
765 
766 #ifdef CONFIG_SYSVIPC
767         struct sysv_sem                 sysvsem;
768         struct sysv_shm                 sysvshm;
769 #endif
770 #ifdef CONFIG_DETECT_HUNG_TASK
771         unsigned long                   last_switch_count;
772 #endif
773         /* Filesystem information: */
774         struct fs_struct                *fs;
775 
776         /* Open file information: */
777         struct files_struct             *files;
778 
779         /* Namespaces: */
780         struct nsproxy                  *nsproxy;
781 
782         /* Signal handlers: */
783         struct signal_struct            *signal;
784         struct sighand_struct           *sighand;
785         sigset_t                        blocked;
786         sigset_t                        real_blocked;
787         /* Restored if set_restore_sigmask() was used: */
788         sigset_t                        saved_sigmask;
789         struct sigpending               pending;
790         unsigned long                   sas_ss_sp;
791         size_t                          sas_ss_size;
792         unsigned int                    sas_ss_flags;
793 
794         struct callback_head            *task_works;
795 
796         struct audit_context            *audit_context;
797 #ifdef CONFIG_AUDITSYSCALL
798         kuid_t                          loginuid;
799         unsigned int                    sessionid;
800 #endif
801         struct seccomp                  seccomp;
802 
803         /* Thread group tracking: */
804         u32                             parent_exec_id;
805         u32                             self_exec_id;
806 
807         /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
808         spinlock_t                      alloc_lock;
809 
810         /* Protection of the PI data structures: */
811         raw_spinlock_t                  pi_lock;
812 
813         struct wake_q_node              wake_q;
814 
815 #ifdef CONFIG_RT_MUTEXES
816         /* PI waiters blocked on a rt_mutex held by this task: */
817         struct rb_root_cached           pi_waiters;
818         /* Updated under owner's pi_lock and rq lock */
819         struct task_struct              *pi_top_task;
820         /* Deadlock detection and priority inheritance handling: */
821         struct rt_mutex_waiter          *pi_blocked_on;
822 #endif
823 
824 #ifdef CONFIG_DEBUG_MUTEXES
825         /* Mutex deadlock detection: */
826         struct mutex_waiter             *blocked_on;
827 #endif
828 
829 #ifdef CONFIG_TRACE_IRQFLAGS
830         unsigned int                    irq_events;
831         unsigned long                   hardirq_enable_ip;
832         unsigned long                   hardirq_disable_ip;
833         unsigned int                    hardirq_enable_event;
834         unsigned int                    hardirq_disable_event;
835         int                             hardirqs_enabled;
836         int                             hardirq_context;
837         unsigned long                   softirq_disable_ip;
838         unsigned long                   softirq_enable_ip;
839         unsigned int                    softirq_disable_event;
840         unsigned int                    softirq_enable_event;
841         int                             softirqs_enabled;
842         int                             softirq_context;
843 #endif
844 
845 #ifdef CONFIG_LOCKDEP
846 # define MAX_LOCK_DEPTH                 48UL
847         u64                             curr_chain_key;
848         int                             lockdep_depth;
849         unsigned int                    lockdep_recursion;
850         struct held_lock                held_locks[MAX_LOCK_DEPTH];
851 #endif
852 
853 #ifdef CONFIG_LOCKDEP_CROSSRELEASE
854 #define MAX_XHLOCKS_NR 64UL
855         struct hist_lock *xhlocks; /* Crossrelease history locks */
856         unsigned int xhlock_idx;
857         /* For restoring at history boundaries */
858         unsigned int xhlock_idx_hist[XHLOCK_CTX_NR];
859         unsigned int hist_id;
860         /* For overwrite check at each context exit */
861         unsigned int hist_id_save[XHLOCK_CTX_NR];
862 #endif
863 
864 #ifdef CONFIG_UBSAN
865         unsigned int                    in_ubsan;
866 #endif
867 
868         /* Journalling filesystem info: */
869         void                            *journal_info;
870 
871         /* Stacked block device info: */
872         struct bio_list                 *bio_list;
873 
874 #ifdef CONFIG_BLOCK
875         /* Stack plugging: */
876         struct blk_plug                 *plug;
877 #endif
878 
879         /* VM state: */
880         struct reclaim_state            *reclaim_state;
881 
882         struct backing_dev_info         *backing_dev_info;
883 
884         struct io_context               *io_context;
885 
886         /* Ptrace state: */
887         unsigned long                   ptrace_message;
888         siginfo_t                       *last_siginfo;
889 
890         struct task_io_accounting       ioac;
891 #ifdef CONFIG_TASK_XACCT
892         /* Accumulated RSS usage: */
893         u64                             acct_rss_mem1;
894         /* Accumulated virtual memory usage: */
895         u64                             acct_vm_mem1;
896         /* stime + utime since last update: */
897         u64                             acct_timexpd;
898 #endif
899 #ifdef CONFIG_CPUSETS
900         /* Protected by ->alloc_lock: */
901         nodemask_t                      mems_allowed;
902         /* Seqence number to catch updates: */
903         seqcount_t                      mems_allowed_seq;
904         int                             cpuset_mem_spread_rotor;
905         int                             cpuset_slab_spread_rotor;
906 #endif
907 #ifdef CONFIG_CGROUPS
908         /* Control Group info protected by css_set_lock: */
909         struct css_set __rcu            *cgroups;
910         /* cg_list protected by css_set_lock and tsk->alloc_lock: */
911         struct list_head                cg_list;
912 #endif
913 #ifdef CONFIG_INTEL_RDT
914         u32                             closid;
915         u32                             rmid;
916 #endif
917 #ifdef CONFIG_FUTEX
918         struct robust_list_head __user  *robust_list;
919 #ifdef CONFIG_COMPAT
920         struct compat_robust_list_head __user *compat_robust_list;
921 #endif
922         struct list_head                pi_state_list;
923         struct futex_pi_state           *pi_state_cache;
924 #endif
925 #ifdef CONFIG_PERF_EVENTS
926         struct perf_event_context       *perf_event_ctxp[perf_nr_task_contexts];
927         struct mutex                    perf_event_mutex;
928         struct list_head                perf_event_list;
929 #endif
930 #ifdef CONFIG_DEBUG_PREEMPT
931         unsigned long                   preempt_disable_ip;
932 #endif
933 #ifdef CONFIG_NUMA
934         /* Protected by alloc_lock: */
935         struct mempolicy                *mempolicy;
936         short                           il_prev;
937         short                           pref_node_fork;
938 #endif
939 #ifdef CONFIG_NUMA_BALANCING
940         int                             numa_scan_seq;
941         unsigned int                    numa_scan_period;
942         unsigned int                    numa_scan_period_max;
943         int                             numa_preferred_nid;
944         unsigned long                   numa_migrate_retry;
945         /* Migration stamp: */
946         u64                             node_stamp;
947         u64                             last_task_numa_placement;
948         u64                             last_sum_exec_runtime;
949         struct callback_head            numa_work;
950 
951         struct list_head                numa_entry;
952         struct numa_group               *numa_group;
953 
954         /*
955          * numa_faults is an array split into four regions:
956          * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
957          * in this precise order.
958          *
959          * faults_memory: Exponential decaying average of faults on a per-node
960          * basis. Scheduling placement decisions are made based on these
961          * counts. The values remain static for the duration of a PTE scan.
962          * faults_cpu: Track the nodes the process was running on when a NUMA
963          * hinting fault was incurred.
964          * faults_memory_buffer and faults_cpu_buffer: Record faults per node
965          * during the current scan window. When the scan completes, the counts
966          * in faults_memory and faults_cpu decay and these values are copied.
967          */
968         unsigned long                   *numa_faults;
969         unsigned long                   total_numa_faults;
970 
971         /*
972          * numa_faults_locality tracks if faults recorded during the last
973          * scan window were remote/local or failed to migrate. The task scan
974          * period is adapted based on the locality of the faults with different
975          * weights depending on whether they were shared or private faults
976          */
977         unsigned long                   numa_faults_locality[3];
978 
979         unsigned long                   numa_pages_migrated;
980 #endif /* CONFIG_NUMA_BALANCING */
981 
982         struct tlbflush_unmap_batch     tlb_ubc;
983 
984         struct rcu_head                 rcu;
985 
986         /* Cache last used pipe for splice(): */
987         struct pipe_inode_info          *splice_pipe;
988 
989         struct page_frag                task_frag;
990 
991 #ifdef CONFIG_TASK_DELAY_ACCT
992         struct task_delay_info          *delays;
993 #endif
994 
995 #ifdef CONFIG_FAULT_INJECTION
996         int                             make_it_fail;
997         unsigned int                    fail_nth;
998 #endif
999         /*
1000          * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1001          * balance_dirty_pages() for a dirty throttling pause:
1002          */
1003         int                             nr_dirtied;
1004         int                             nr_dirtied_pause;
1005         /* Start of a write-and-pause period: */
1006         unsigned long                   dirty_paused_when;
1007 
1008 #ifdef CONFIG_LATENCYTOP
1009         int                             latency_record_count;
1010         struct latency_record           latency_record[LT_SAVECOUNT];
1011 #endif
1012         /*
1013          * Time slack values; these are used to round up poll() and
1014          * select() etc timeout values. These are in nanoseconds.
1015          */
1016         u64                             timer_slack_ns;
1017         u64                             default_timer_slack_ns;
1018 
1019 #ifdef CONFIG_KASAN
1020         unsigned int                    kasan_depth;
1021 #endif
1022 
1023 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1024         /* Index of current stored address in ret_stack: */
1025         int                             curr_ret_stack;
1026 
1027         /* Stack of return addresses for return function tracing: */
1028         struct ftrace_ret_stack         *ret_stack;
1029 
1030         /* Timestamp for last schedule: */
1031         unsigned long long              ftrace_timestamp;
1032 
1033         /*
1034          * Number of functions that haven't been traced
1035          * because of depth overrun:
1036          */
1037         atomic_t                        trace_overrun;
1038 
1039         /* Pause tracing: */
1040         atomic_t                        tracing_graph_pause;
1041 #endif
1042 
1043 #ifdef CONFIG_TRACING
1044         /* State flags for use by tracers: */
1045         unsigned long                   trace;
1046 
1047         /* Bitmask and counter of trace recursion: */
1048         unsigned long                   trace_recursion;
1049 #endif /* CONFIG_TRACING */
1050 
1051 #ifdef CONFIG_KCOV
1052         /* Coverage collection mode enabled for this task (0 if disabled): */
1053         enum kcov_mode                  kcov_mode;
1054 
1055         /* Size of the kcov_area: */
1056         unsigned int                    kcov_size;
1057 
1058         /* Buffer for coverage collection: */
1059         void                            *kcov_area;
1060 
1061         /* KCOV descriptor wired with this task or NULL: */
1062         struct kcov                     *kcov;
1063 #endif
1064 
1065 #ifdef CONFIG_MEMCG
1066         struct mem_cgroup               *memcg_in_oom;
1067         gfp_t                           memcg_oom_gfp_mask;
1068         int                             memcg_oom_order;
1069 
1070         /* Number of pages to reclaim on returning to userland: */
1071         unsigned int                    memcg_nr_pages_over_high;
1072 #endif
1073 
1074 #ifdef CONFIG_UPROBES
1075         struct uprobe_task              *utask;
1076 #endif
1077 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1078         unsigned int                    sequential_io;
1079         unsigned int                    sequential_io_avg;
1080 #endif
1081 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1082         unsigned long                   task_state_change;
1083 #endif
1084         int                             pagefault_disabled;
1085 #ifdef CONFIG_MMU
1086         struct task_struct              *oom_reaper_list;
1087 #endif
1088 #ifdef CONFIG_VMAP_STACK
1089         struct vm_struct                *stack_vm_area;
1090 #endif
1091 #ifdef CONFIG_THREAD_INFO_IN_TASK
1092         /* A live task holds one reference: */
1093         atomic_t                        stack_refcount;
1094 #endif
1095 #ifdef CONFIG_LIVEPATCH
1096         int patch_state;
1097 #endif
1098 #ifdef CONFIG_SECURITY
1099         /* Used by LSM modules for access restriction: */
1100         void                            *security;
1101 #endif
1102 #if defined(CONFIG_CCSECURITY) && !defined(CONFIG_CCSECURITY_USE_EXTERNAL_TASK_SECURITY)
1103         struct ccs_domain_info          *ccs_domain_info;
1104         u32                             ccs_flags;
1105 #endif
1106 
1107         /*
1108          * New fields for task_struct should be added above here, so that
1109          * they are included in the randomized portion of task_struct.
1110          */
1111         randomized_struct_fields_end
1112 
1113         /* CPU-specific state of this task: */
1114         struct thread_struct            thread;
1115 
1116         /*
1117          * WARNING: on x86, 'thread_struct' contains a variable-sized
1118          * structure.  It *MUST* be at the end of 'task_struct'.
1119          *
1120          * Do not put anything below here!
1121          */
1122 };
1123 
1124 static inline struct pid *task_pid(struct task_struct *task)
1125 {
1126         return task->pids[PIDTYPE_PID].pid;
1127 }
1128 
1129 static inline struct pid *task_tgid(struct task_struct *task)
1130 {
1131         return task->group_leader->pids[PIDTYPE_PID].pid;
1132 }
1133 
1134 /*
1135  * Without tasklist or RCU lock it is not safe to dereference
1136  * the result of task_pgrp/task_session even if task == current,
1137  * we can race with another thread doing sys_setsid/sys_setpgid.
1138  */
1139 static inline struct pid *task_pgrp(struct task_struct *task)
1140 {
1141         return task->group_leader->pids[PIDTYPE_PGID].pid;
1142 }
1143 
1144 static inline struct pid *task_session(struct task_struct *task)
1145 {
1146         return task->group_leader->pids[PIDTYPE_SID].pid;
1147 }
1148 
1149 /*
1150  * the helpers to get the task's different pids as they are seen
1151  * from various namespaces
1152  *
1153  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1154  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1155  *                     current.
1156  * task_xid_nr_ns()  : id seen from the ns specified;
1157  *
1158  * see also pid_nr() etc in include/linux/pid.h
1159  */
1160 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1161 
1162 static inline pid_t task_pid_nr(struct task_struct *tsk)
1163 {
1164         return tsk->pid;
1165 }
1166 
1167 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1168 {
1169         return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1170 }
1171 
1172 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1173 {
1174         return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1175 }
1176 
1177 
1178 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1179 {
1180         return tsk->tgid;
1181 }
1182 
1183 /**
1184  * pid_alive - check that a task structure is not stale
1185  * @p: Task structure to be checked.
1186  *
1187  * Test if a process is not yet dead (at most zombie state)
1188  * If pid_alive fails, then pointers within the task structure
1189  * can be stale and must not be dereferenced.
1190  *
1191  * Return: 1 if the process is alive. 0 otherwise.
1192  */
1193 static inline int pid_alive(const struct task_struct *p)
1194 {
1195         return p->pids[PIDTYPE_PID].pid != NULL;
1196 }
1197 
1198 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1199 {
1200         return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1201 }
1202 
1203 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1204 {
1205         return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1206 }
1207 
1208 
1209 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1210 {
1211         return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1212 }
1213 
1214 static inline pid_t task_session_vnr(struct task_struct *tsk)
1215 {
1216         return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1217 }
1218 
1219 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1220 {
1221         return __task_pid_nr_ns(tsk, __PIDTYPE_TGID, ns);
1222 }
1223 
1224 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1225 {
1226         return __task_pid_nr_ns(tsk, __PIDTYPE_TGID, NULL);
1227 }
1228 
1229 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1230 {
1231         pid_t pid = 0;
1232 
1233         rcu_read_lock();
1234         if (pid_alive(tsk))
1235                 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1236         rcu_read_unlock();
1237 
1238         return pid;
1239 }
1240 
1241 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1242 {
1243         return task_ppid_nr_ns(tsk, &init_pid_ns);
1244 }
1245 
1246 /* Obsolete, do not use: */
1247 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1248 {
1249         return task_pgrp_nr_ns(tsk, &init_pid_ns);
1250 }
1251 
1252 #define TASK_REPORT_IDLE        (TASK_REPORT + 1)
1253 #define TASK_REPORT_MAX         (TASK_REPORT_IDLE << 1)
1254 
1255 static inline unsigned int task_state_index(struct task_struct *tsk)
1256 {
1257         unsigned int tsk_state = READ_ONCE(tsk->state);
1258         unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1259 
1260         BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1261 
1262         if (tsk_state == TASK_IDLE)
1263                 state = TASK_REPORT_IDLE;
1264 
1265         return fls(state);
1266 }
1267 
1268 static inline char task_index_to_char(unsigned int state)
1269 {
1270         static const char state_char[] = "RSDTtXZPI";
1271 
1272         BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1273 
1274         return state_char[state];
1275 }
1276 
1277 static inline char task_state_to_char(struct task_struct *tsk)
1278 {
1279         return task_index_to_char(task_state_index(tsk));
1280 }
1281 
1282 /**
1283  * is_global_init - check if a task structure is init. Since init
1284  * is free to have sub-threads we need to check tgid.
1285  * @tsk: Task structure to be checked.
1286  *
1287  * Check if a task structure is the first user space task the kernel created.
1288  *
1289  * Return: 1 if the task structure is init. 0 otherwise.
1290  */
1291 static inline int is_global_init(struct task_struct *tsk)
1292 {
1293         return task_tgid_nr(tsk) == 1;
1294 }
1295 
1296 extern struct pid *cad_pid;
1297 
1298 /*
1299  * Per process flags
1300  */
1301 #define PF_IDLE                 0x00000002      /* I am an IDLE thread */
1302 #define PF_EXITING              0x00000004      /* Getting shut down */
1303 #define PF_EXITPIDONE           0x00000008      /* PI exit done on shut down */
1304 #define PF_VCPU                 0x00000010      /* I'm a virtual CPU */
1305 #define PF_WQ_WORKER            0x00000020      /* I'm a workqueue worker */
1306 #define PF_FORKNOEXEC           0x00000040      /* Forked but didn't exec */
1307 #define PF_MCE_PROCESS          0x00000080      /* Process policy on mce errors */
1308 #define PF_SUPERPRIV            0x00000100      /* Used super-user privileges */
1309 #define PF_DUMPCORE             0x00000200      /* Dumped core */
1310 #define PF_SIGNALED             0x00000400      /* Killed by a signal */
1311 #define PF_MEMALLOC             0x00000800      /* Allocating memory */
1312 #define PF_NPROC_EXCEEDED       0x00001000      /* set_user() noticed that RLIMIT_NPROC was exceeded */
1313 #define PF_USED_MATH            0x00002000      /* If unset the fpu must be initialized before use */
1314 #define PF_USED_ASYNC           0x00004000      /* Used async_schedule*(), used by module init */
1315 #define PF_NOFREEZE             0x00008000      /* This thread should not be frozen */
1316 #define PF_FROZEN               0x00010000      /* Frozen for system suspend */
1317 #define PF_KSWAPD               0x00020000      /* I am kswapd */
1318 #define PF_MEMALLOC_NOFS        0x00040000      /* All allocation requests will inherit GFP_NOFS */
1319 #define PF_MEMALLOC_NOIO        0x00080000      /* All allocation requests will inherit GFP_NOIO */
1320 #define PF_LESS_THROTTLE        0x00100000      /* Throttle me less: I clean memory */
1321 #define PF_KTHREAD              0x00200000      /* I am a kernel thread */
1322 #define PF_RANDOMIZE            0x00400000      /* Randomize virtual address space */
1323 #define PF_SWAPWRITE            0x00800000      /* Allowed to write to swap */
1324 #define PF_NO_SETAFFINITY       0x04000000      /* Userland is not allowed to meddle with cpus_allowed */
1325 #define PF_MCE_EARLY            0x08000000      /* Early kill for mce process policy */
1326 #define PF_MUTEX_TESTER         0x20000000      /* Thread belongs to the rt mutex tester */
1327 #define PF_FREEZER_SKIP         0x40000000      /* Freezer should not count it as freezable */
1328 #define PF_SUSPEND_TASK         0x80000000      /* This thread called freeze_processes() and should not be frozen */
1329 
1330 /*
1331  * Only the _current_ task can read/write to tsk->flags, but other
1332  * tasks can access tsk->flags in readonly mode for example
1333  * with tsk_used_math (like during threaded core dumping).
1334  * There is however an exception to this rule during ptrace
1335  * or during fork: the ptracer task is allowed to write to the
1336  * child->flags of its traced child (same goes for fork, the parent
1337  * can write to the child->flags), because we're guaranteed the
1338  * child is not running and in turn not changing child->flags
1339  * at the same time the parent does it.
1340  */
1341 #define clear_stopped_child_used_math(child)    do { (child)->flags &= ~PF_USED_MATH; } while (0)
1342 #define set_stopped_child_used_math(child)      do { (child)->flags |= PF_USED_MATH; } while (0)
1343 #define clear_used_math()                       clear_stopped_child_used_math(current)
1344 #define set_used_math()                         set_stopped_child_used_math(current)
1345 
1346 #define conditional_stopped_child_used_math(condition, child) \
1347         do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1348 
1349 #define conditional_used_math(condition)        conditional_stopped_child_used_math(condition, current)
1350 
1351 #define copy_to_stopped_child_used_math(child) \
1352         do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1353 
1354 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1355 #define tsk_used_math(p)                        ((p)->flags & PF_USED_MATH)
1356 #define used_math()                             tsk_used_math(current)
1357 
1358 static inline bool is_percpu_thread(void)
1359 {
1360 #ifdef CONFIG_SMP
1361         return (current->flags & PF_NO_SETAFFINITY) &&
1362                 (current->nr_cpus_allowed  == 1);
1363 #else
1364         return true;
1365 #endif
1366 }
1367 
1368 /* Per-process atomic flags. */
1369 #define PFA_NO_NEW_PRIVS                0       /* May not gain new privileges. */
1370 #define PFA_SPREAD_PAGE                 1       /* Spread page cache over cpuset */
1371 #define PFA_SPREAD_SLAB                 2       /* Spread some slab caches over cpuset */
1372 
1373 
1374 #define TASK_PFA_TEST(name, func)                                       \
1375         static inline bool task_##func(struct task_struct *p)           \
1376         { return test_bit(PFA_##name, &p->atomic_flags); }
1377 
1378 #define TASK_PFA_SET(name, func)                                        \
1379         static inline void task_set_##func(struct task_struct *p)       \
1380         { set_bit(PFA_##name, &p->atomic_flags); }
1381 
1382 #define TASK_PFA_CLEAR(name, func)                                      \
1383         static inline void task_clear_##func(struct task_struct *p)     \
1384         { clear_bit(PFA_##name, &p->atomic_flags); }
1385 
1386 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1387 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1388 
1389 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1390 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1391 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1392 
1393 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1394 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1395 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1396 
1397 static inline void
1398 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1399 {
1400         current->flags &= ~flags;
1401         current->flags |= orig_flags & flags;
1402 }
1403 
1404 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1405 extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
1406 #ifdef CONFIG_SMP
1407 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1408 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1409 #else
1410 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1411 {
1412 }
1413 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1414 {
1415         if (!cpumask_test_cpu(0, new_mask))
1416                 return -EINVAL;
1417         return 0;
1418 }
1419 #endif
1420 
1421 #ifndef cpu_relax_yield
1422 #define cpu_relax_yield() cpu_relax()
1423 #endif
1424 
1425 extern int yield_to(struct task_struct *p, bool preempt);
1426 extern void set_user_nice(struct task_struct *p, long nice);
1427 extern int task_prio(const struct task_struct *p);
1428 
1429 /**
1430  * task_nice - return the nice value of a given task.
1431  * @p: the task in question.
1432  *
1433  * Return: The nice value [ -20 ... 0 ... 19 ].
1434  */
1435 static inline int task_nice(const struct task_struct *p)
1436 {
1437         return PRIO_TO_NICE((p)->static_prio);
1438 }
1439 
1440 extern int can_nice(const struct task_struct *p, const int nice);
1441 extern int task_curr(const struct task_struct *p);
1442 extern int idle_cpu(int cpu);
1443 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1444 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1445 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1446 extern struct task_struct *idle_task(int cpu);
1447 
1448 /**
1449  * is_idle_task - is the specified task an idle task?
1450  * @p: the task in question.
1451  *
1452  * Return: 1 if @p is an idle task. 0 otherwise.
1453  */
1454 static inline bool is_idle_task(const struct task_struct *p)
1455 {
1456         return !!(p->flags & PF_IDLE);
1457 }
1458 
1459 extern struct task_struct *curr_task(int cpu);
1460 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1461 
1462 void yield(void);
1463 
1464 union thread_union {
1465 #ifndef CONFIG_THREAD_INFO_IN_TASK
1466         struct thread_info thread_info;
1467 #endif
1468         unsigned long stack[THREAD_SIZE/sizeof(long)];
1469 };
1470 
1471 #ifdef CONFIG_THREAD_INFO_IN_TASK
1472 static inline struct thread_info *task_thread_info(struct task_struct *task)
1473 {
1474         return &task->thread_info;
1475 }
1476 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1477 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1478 #endif
1479 
1480 /*
1481  * find a task by one of its numerical ids
1482  *
1483  * find_task_by_pid_ns():
1484  *      finds a task by its pid in the specified namespace
1485  * find_task_by_vpid():
1486  *      finds a task by its virtual pid
1487  *
1488  * see also find_vpid() etc in include/linux/pid.h
1489  */
1490 
1491 extern struct task_struct *find_task_by_vpid(pid_t nr);
1492 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1493 
1494 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1495 extern int wake_up_process(struct task_struct *tsk);
1496 extern void wake_up_new_task(struct task_struct *tsk);
1497 
1498 #ifdef CONFIG_SMP
1499 extern void kick_process(struct task_struct *tsk);
1500 #else
1501 static inline void kick_process(struct task_struct *tsk) { }
1502 #endif
1503 
1504 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1505 
1506 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1507 {
1508         __set_task_comm(tsk, from, false);
1509 }
1510 
1511 extern char *get_task_comm(char *to, struct task_struct *tsk);
1512 
1513 #ifdef CONFIG_SMP
1514 void scheduler_ipi(void);
1515 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
1516 #else
1517 static inline void scheduler_ipi(void) { }
1518 static inline unsigned long wait_task_inactive(struct task_struct *p, long match_state)
1519 {
1520         return 1;
1521 }
1522 #endif
1523 
1524 /*
1525  * Set thread flags in other task's structures.
1526  * See asm/thread_info.h for TIF_xxxx flags available:
1527  */
1528 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1529 {
1530         set_ti_thread_flag(task_thread_info(tsk), flag);
1531 }
1532 
1533 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1534 {
1535         clear_ti_thread_flag(task_thread_info(tsk), flag);
1536 }
1537 
1538 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1539 {
1540         return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1541 }
1542 
1543 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1544 {
1545         return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1546 }
1547 
1548 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1549 {
1550         return test_ti_thread_flag(task_thread_info(tsk), flag);
1551 }
1552 
1553 static inline void set_tsk_need_resched(struct task_struct *tsk)
1554 {
1555         set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1556 }
1557 
1558 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1559 {
1560         clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1561 }
1562 
1563 static inline int test_tsk_need_resched(struct task_struct *tsk)
1564 {
1565         return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1566 }
1567 
1568 /*
1569  * cond_resched() and cond_resched_lock(): latency reduction via
1570  * explicit rescheduling in places that are safe. The return
1571  * value indicates whether a reschedule was done in fact.
1572  * cond_resched_lock() will drop the spinlock before scheduling,
1573  * cond_resched_softirq() will enable bhs before scheduling.
1574  */
1575 #ifndef CONFIG_PREEMPT
1576 extern int _cond_resched(void);
1577 #else
1578 static inline int _cond_resched(void) { return 0; }
1579 #endif
1580 
1581 #define cond_resched() ({                       \
1582         ___might_sleep(__FILE__, __LINE__, 0);  \
1583         _cond_resched();                        \
1584 })
1585 
1586 extern int __cond_resched_lock(spinlock_t *lock);
1587 
1588 #define cond_resched_lock(lock) ({                              \
1589         ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
1590         __cond_resched_lock(lock);                              \
1591 })
1592 
1593 extern int __cond_resched_softirq(void);
1594 
1595 #define cond_resched_softirq() ({                                       \
1596         ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);     \
1597         __cond_resched_softirq();                                       \
1598 })
1599 
1600 static inline void cond_resched_rcu(void)
1601 {
1602 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
1603         rcu_read_unlock();
1604         cond_resched();
1605         rcu_read_lock();
1606 #endif
1607 }
1608 
1609 /*
1610  * Does a critical section need to be broken due to another
1611  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
1612  * but a general need for low latency)
1613  */
1614 static inline int spin_needbreak(spinlock_t *lock)
1615 {
1616 #ifdef CONFIG_PREEMPT
1617         return spin_is_contended(lock);
1618 #else
1619         return 0;
1620 #endif
1621 }
1622 
1623 static __always_inline bool need_resched(void)
1624 {
1625         return unlikely(tif_need_resched());
1626 }
1627 
1628 /*
1629  * Wrappers for p->thread_info->cpu access. No-op on UP.
1630  */
1631 #ifdef CONFIG_SMP
1632 
1633 static inline unsigned int task_cpu(const struct task_struct *p)
1634 {
1635 #ifdef CONFIG_THREAD_INFO_IN_TASK
1636         return p->cpu;
1637 #else
1638         return task_thread_info(p)->cpu;
1639 #endif
1640 }
1641 
1642 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
1643 
1644 #else
1645 
1646 static inline unsigned int task_cpu(const struct task_struct *p)
1647 {
1648         return 0;
1649 }
1650 
1651 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1652 {
1653 }
1654 
1655 #endif /* CONFIG_SMP */
1656 
1657 /*
1658  * In order to reduce various lock holder preemption latencies provide an
1659  * interface to see if a vCPU is currently running or not.
1660  *
1661  * This allows us to terminate optimistic spin loops and block, analogous to
1662  * the native optimistic spin heuristic of testing if the lock owner task is
1663  * running or not.
1664  */
1665 #ifndef vcpu_is_preempted
1666 # define vcpu_is_preempted(cpu) false
1667 #endif
1668 
1669 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
1670 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
1671 
1672 #ifndef TASK_SIZE_OF
1673 #define TASK_SIZE_OF(tsk)       TASK_SIZE
1674 #endif
1675 
1676 #endif
1677 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp