source: src/linux/universal/linux-4.9/include/linux/sched.h @ 31885

Last change on this file since 31885 was 31885, checked in by brainslayer, 3 months ago

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1#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
4#include <uapi/linux/sched.h>
5
6#include <linux/sched/prio.h>
7
8
9struct sched_param {
10        int sched_priority;
11};
12
13#include <asm/param.h>  /* for HZ */
14
15#include <linux/capability.h>
16#include <linux/threads.h>
17#include <linux/kernel.h>
18#include <linux/types.h>
19#include <linux/timex.h>
20#include <linux/jiffies.h>
21#include <linux/plist.h>
22#include <linux/rbtree.h>
23#include <linux/thread_info.h>
24#include <linux/cpumask.h>
25#include <linux/errno.h>
26#include <linux/nodemask.h>
27#include <linux/mm_types.h>
28#include <linux/preempt.h>
29
30#include <asm/page.h>
31#include <asm/ptrace.h>
32#include <linux/cputime.h>
33
34#include <linux/smp.h>
35#include <linux/sem.h>
36#include <linux/shm.h>
37#include <linux/signal.h>
38#include <linux/compiler.h>
39#include <linux/completion.h>
40#include <linux/pid.h>
41#include <linux/percpu.h>
42#include <linux/topology.h>
43#include <linux/seccomp.h>
44#include <linux/rcupdate.h>
45#include <linux/rculist.h>
46#include <linux/rtmutex.h>
47
48#include <linux/time.h>
49#include <linux/param.h>
50#include <linux/resource.h>
51#include <linux/timer.h>
52#include <linux/hrtimer.h>
53#include <linux/kcov.h>
54#include <linux/task_io_accounting.h>
55#include <linux/latencytop.h>
56#include <linux/cred.h>
57#include <linux/llist.h>
58#include <linux/uidgid.h>
59#include <linux/gfp.h>
60#include <linux/magic.h>
61#include <linux/cgroup-defs.h>
62
63#include <asm/processor.h>
64
65#define SCHED_ATTR_SIZE_VER0    48      /* sizeof first published struct */
66
67/*
68 * Extended scheduling parameters data structure.
69 *
70 * This is needed because the original struct sched_param can not be
71 * altered without introducing ABI issues with legacy applications
72 * (e.g., in sched_getparam()).
73 *
74 * However, the possibility of specifying more than just a priority for
75 * the tasks may be useful for a wide variety of application fields, e.g.,
76 * multimedia, streaming, automation and control, and many others.
77 *
78 * This variant (sched_attr) is meant at describing a so-called
79 * sporadic time-constrained task. In such model a task is specified by:
80 *  - the activation period or minimum instance inter-arrival time;
81 *  - the maximum (or average, depending on the actual scheduling
82 *    discipline) computation time of all instances, a.k.a. runtime;
83 *  - the deadline (relative to the actual activation time) of each
84 *    instance.
85 * Very briefly, a periodic (sporadic) task asks for the execution of
86 * some specific computation --which is typically called an instance--
87 * (at most) every period. Moreover, each instance typically lasts no more
88 * than the runtime and must be completed by time instant t equal to
89 * the instance activation time + the deadline.
90 *
91 * This is reflected by the actual fields of the sched_attr structure:
92 *
93 *  @size               size of the structure, for fwd/bwd compat.
94 *
95 *  @sched_policy       task's scheduling policy
96 *  @sched_flags        for customizing the scheduler behaviour
97 *  @sched_nice         task's nice value      (SCHED_NORMAL/BATCH)
98 *  @sched_priority     task's static priority (SCHED_FIFO/RR)
99 *  @sched_deadline     representative of the task's deadline
100 *  @sched_runtime      representative of the task's runtime
101 *  @sched_period       representative of the task's period
102 *
103 * Given this task model, there are a multiplicity of scheduling algorithms
104 * and policies, that can be used to ensure all the tasks will make their
105 * timing constraints.
106 *
107 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
108 * only user of this new interface. More information about the algorithm
109 * available in the scheduling class file or in Documentation/.
110 */
111struct sched_attr {
112        u32 size;
113
114        u32 sched_policy;
115        u64 sched_flags;
116
117        /* SCHED_NORMAL, SCHED_BATCH */
118        s32 sched_nice;
119
120        /* SCHED_FIFO, SCHED_RR */
121        u32 sched_priority;
122
123        /* SCHED_DEADLINE */
124        u64 sched_runtime;
125        u64 sched_deadline;
126        u64 sched_period;
127};
128
129struct futex_pi_state;
130struct robust_list_head;
131struct bio_list;
132struct fs_struct;
133struct perf_event_context;
134struct blk_plug;
135struct filename;
136struct nameidata;
137
138#define VMACACHE_BITS 2
139#define VMACACHE_SIZE (1U << VMACACHE_BITS)
140#define VMACACHE_MASK (VMACACHE_SIZE - 1)
141
142/*
143 * These are the constant used to fake the fixed-point load-average
144 * counting. Some notes:
145 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
146 *    a load-average precision of 10 bits integer + 11 bits fractional
147 *  - if you want to count load-averages more often, you need more
148 *    precision, or rounding will get you. With 2-second counting freq,
149 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
150 *    11 bit fractions.
151 */
152extern unsigned long avenrun[];         /* Load averages */
153extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
154
155#define FSHIFT          11              /* nr of bits of precision */
156#define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
157#define LOAD_FREQ       (5*HZ+1)        /* 5 sec intervals */
158#define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
159#define EXP_5           2014            /* 1/exp(5sec/5min) */
160#define EXP_15          2037            /* 1/exp(5sec/15min) */
161
162#define CALC_LOAD(load,exp,n) \
163        load *= exp; \
164        load += n*(FIXED_1-exp); \
165        load >>= FSHIFT;
166
167extern unsigned long total_forks;
168extern int nr_threads;
169DECLARE_PER_CPU(unsigned long, process_counts);
170extern int nr_processes(void);
171extern unsigned long nr_running(void);
172extern bool single_task_running(void);
173extern unsigned long nr_iowait(void);
174extern unsigned long nr_iowait_cpu(int cpu);
175extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
176
177extern void calc_global_load(unsigned long ticks);
178
179#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
180extern void cpu_load_update_nohz_start(void);
181extern void cpu_load_update_nohz_stop(void);
182#else
183static inline void cpu_load_update_nohz_start(void) { }
184static inline void cpu_load_update_nohz_stop(void) { }
185#endif
186
187extern void dump_cpu_task(int cpu);
188
189struct seq_file;
190struct cfs_rq;
191struct task_group;
192#ifdef CONFIG_SCHED_DEBUG
193extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
194extern void proc_sched_set_task(struct task_struct *p);
195#endif
196
197/*
198 * Task state bitmask. NOTE! These bits are also
199 * encoded in fs/proc/array.c: get_task_state().
200 *
201 * We have two separate sets of flags: task->state
202 * is about runnability, while task->exit_state are
203 * about the task exiting. Confusing, but this way
204 * modifying one set can't modify the other one by
205 * mistake.
206 */
207#define TASK_RUNNING            0
208#define TASK_INTERRUPTIBLE      1
209#define TASK_UNINTERRUPTIBLE    2
210#define __TASK_STOPPED          4
211#define __TASK_TRACED           8
212/* in tsk->exit_state */
213#define EXIT_DEAD               16
214#define EXIT_ZOMBIE             32
215#define EXIT_TRACE              (EXIT_ZOMBIE | EXIT_DEAD)
216/* in tsk->state again */
217#define TASK_DEAD               64
218#define TASK_WAKEKILL           128
219#define TASK_WAKING             256
220#define TASK_PARKED             512
221#define TASK_NOLOAD             1024
222#define TASK_NEW                2048
223#define TASK_STATE_MAX          4096
224
225#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPNn"
226
227extern char ___assert_task_state[1 - 2*!!(
228                sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
229
230/* Convenience macros for the sake of set_task_state */
231#define TASK_KILLABLE           (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
232#define TASK_STOPPED            (TASK_WAKEKILL | __TASK_STOPPED)
233#define TASK_TRACED             (TASK_WAKEKILL | __TASK_TRACED)
234
235#define TASK_IDLE               (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
236
237/* Convenience macros for the sake of wake_up */
238#define TASK_NORMAL             (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
239#define TASK_ALL                (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
240
241/* get_task_state() */
242#define TASK_REPORT             (TASK_RUNNING | TASK_INTERRUPTIBLE | \
243                                 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
244                                 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
245
246#define task_is_traced(task)    ((task->state & __TASK_TRACED) != 0)
247#define task_is_stopped(task)   ((task->state & __TASK_STOPPED) != 0)
248#define task_is_stopped_or_traced(task) \
249                        ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
250#define task_contributes_to_load(task)  \
251                                ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
252                                 (task->flags & PF_FROZEN) == 0 && \
253                                 (task->state & TASK_NOLOAD) == 0)
254
255#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
256
257#define __set_task_state(tsk, state_value)                      \
258        do {                                                    \
259                (tsk)->task_state_change = _THIS_IP_;           \
260                (tsk)->state = (state_value);                   \
261        } while (0)
262#define set_task_state(tsk, state_value)                        \
263        do {                                                    \
264                (tsk)->task_state_change = _THIS_IP_;           \
265                smp_store_mb((tsk)->state, (state_value));              \
266        } while (0)
267
268/*
269 * set_current_state() includes a barrier so that the write of current->state
270 * is correctly serialised wrt the caller's subsequent test of whether to
271 * actually sleep:
272 *
273 *      set_current_state(TASK_UNINTERRUPTIBLE);
274 *      if (do_i_need_to_sleep())
275 *              schedule();
276 *
277 * If the caller does not need such serialisation then use __set_current_state()
278 */
279#define __set_current_state(state_value)                        \
280        do {                                                    \
281                current->task_state_change = _THIS_IP_;         \
282                current->state = (state_value);                 \
283        } while (0)
284#define set_current_state(state_value)                          \
285        do {                                                    \
286                current->task_state_change = _THIS_IP_;         \
287                smp_store_mb(current->state, (state_value));            \
288        } while (0)
289
290#else
291
292#define __set_task_state(tsk, state_value)              \
293        do { (tsk)->state = (state_value); } while (0)
294#define set_task_state(tsk, state_value)                \
295        smp_store_mb((tsk)->state, (state_value))
296
297/*
298 * set_current_state() includes a barrier so that the write of current->state
299 * is correctly serialised wrt the caller's subsequent test of whether to
300 * actually sleep:
301 *
302 *      set_current_state(TASK_UNINTERRUPTIBLE);
303 *      if (do_i_need_to_sleep())
304 *              schedule();
305 *
306 * If the caller does not need such serialisation then use __set_current_state()
307 */
308#define __set_current_state(state_value)                \
309        do { current->state = (state_value); } while (0)
310#define set_current_state(state_value)                  \
311        smp_store_mb(current->state, (state_value))
312
313#endif
314
315/* Task command name length */
316#define TASK_COMM_LEN 16
317
318#include <linux/spinlock.h>
319
320/*
321 * This serializes "schedule()" and also protects
322 * the run-queue from deletions/modifications (but
323 * _adding_ to the beginning of the run-queue has
324 * a separate lock).
325 */
326extern rwlock_t tasklist_lock;
327extern spinlock_t mmlist_lock;
328
329struct task_struct;
330
331#ifdef CONFIG_PROVE_RCU
332extern int lockdep_tasklist_lock_is_held(void);
333#endif /* #ifdef CONFIG_PROVE_RCU */
334
335extern void sched_init(void);
336extern void sched_init_smp(void);
337extern asmlinkage void schedule_tail(struct task_struct *prev);
338extern void init_idle(struct task_struct *idle, int cpu);
339extern void init_idle_bootup_task(struct task_struct *idle);
340
341extern cpumask_var_t cpu_isolated_map;
342
343extern int runqueue_is_locked(int cpu);
344
345#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
346extern void nohz_balance_enter_idle(int cpu);
347extern void set_cpu_sd_state_idle(void);
348extern int get_nohz_timer_target(void);
349#else
350static inline void nohz_balance_enter_idle(int cpu) { }
351static inline void set_cpu_sd_state_idle(void) { }
352#endif
353
354/*
355 * Only dump TASK_* tasks. (0 for all tasks)
356 */
357extern void show_state_filter(unsigned long state_filter);
358
359static inline void show_state(void)
360{
361        show_state_filter(0);
362}
363
364extern void show_regs(struct pt_regs *);
365
366/*
367 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
368 * task), SP is the stack pointer of the first frame that should be shown in the back
369 * trace (or NULL if the entire call-chain of the task should be shown).
370 */
371extern void show_stack(struct task_struct *task, unsigned long *sp);
372
373extern void cpu_init (void);
374extern void trap_init(void);
375extern void update_process_times(int user);
376extern void scheduler_tick(void);
377extern int sched_cpu_starting(unsigned int cpu);
378extern int sched_cpu_activate(unsigned int cpu);
379extern int sched_cpu_deactivate(unsigned int cpu);
380
381#ifdef CONFIG_HOTPLUG_CPU
382extern int sched_cpu_dying(unsigned int cpu);
383#else
384# define sched_cpu_dying        NULL
385#endif
386
387extern void sched_show_task(struct task_struct *p);
388
389#ifdef CONFIG_LOCKUP_DETECTOR
390extern void touch_softlockup_watchdog_sched(void);
391extern void touch_softlockup_watchdog(void);
392extern void touch_softlockup_watchdog_sync(void);
393extern void touch_all_softlockup_watchdogs(void);
394extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
395                                  void __user *buffer,
396                                  size_t *lenp, loff_t *ppos);
397extern unsigned int  softlockup_panic;
398extern unsigned int  hardlockup_panic;
399void lockup_detector_init(void);
400#else
401static inline void touch_softlockup_watchdog_sched(void)
402{
403}
404static inline void touch_softlockup_watchdog(void)
405{
406}
407static inline void touch_softlockup_watchdog_sync(void)
408{
409}
410static inline void touch_all_softlockup_watchdogs(void)
411{
412}
413static inline void lockup_detector_init(void)
414{
415}
416#endif
417
418#ifdef CONFIG_DETECT_HUNG_TASK
419void reset_hung_task_detector(void);
420#else
421static inline void reset_hung_task_detector(void)
422{
423}
424#endif
425
426/* Attach to any functions which should be ignored in wchan output. */
427#define __sched         __attribute__((__section__(".sched.text")))
428
429/* Linker adds these: start and end of __sched functions */
430extern char __sched_text_start[], __sched_text_end[];
431
432/* Is this address in the __sched functions? */
433extern int in_sched_functions(unsigned long addr);
434
435#define MAX_SCHEDULE_TIMEOUT    LONG_MAX
436extern signed long schedule_timeout(signed long timeout);
437extern signed long schedule_timeout_interruptible(signed long timeout);
438extern signed long schedule_timeout_killable(signed long timeout);
439extern signed long schedule_timeout_uninterruptible(signed long timeout);
440extern signed long schedule_timeout_idle(signed long timeout);
441asmlinkage void schedule(void);
442extern void schedule_preempt_disabled(void);
443
444extern long io_schedule_timeout(long timeout);
445
446static inline void io_schedule(void)
447{
448        io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
449}
450
451void __noreturn do_task_dead(void);
452
453struct nsproxy;
454struct user_namespace;
455
456#ifdef CONFIG_MMU
457extern void arch_pick_mmap_layout(struct mm_struct *mm);
458extern unsigned long
459arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
460                       unsigned long, unsigned long);
461extern unsigned long
462arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
463                          unsigned long len, unsigned long pgoff,
464                          unsigned long flags);
465#else
466static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
467#endif
468
469#define SUID_DUMP_DISABLE       0       /* No setuid dumping */
470#define SUID_DUMP_USER          1       /* Dump as user of process */
471#define SUID_DUMP_ROOT          2       /* Dump as root */
472
473/* mm flags */
474
475/* for SUID_DUMP_* above */
476#define MMF_DUMPABLE_BITS 2
477#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
478
479extern void set_dumpable(struct mm_struct *mm, int value);
480/*
481 * This returns the actual value of the suid_dumpable flag. For things
482 * that are using this for checking for privilege transitions, it must
483 * test against SUID_DUMP_USER rather than treating it as a boolean
484 * value.
485 */
486static inline int __get_dumpable(unsigned long mm_flags)
487{
488        return mm_flags & MMF_DUMPABLE_MASK;
489}
490
491static inline int get_dumpable(struct mm_struct *mm)
492{
493        return __get_dumpable(mm->flags);
494}
495
496/* coredump filter bits */
497#define MMF_DUMP_ANON_PRIVATE   2
498#define MMF_DUMP_ANON_SHARED    3
499#define MMF_DUMP_MAPPED_PRIVATE 4
500#define MMF_DUMP_MAPPED_SHARED  5
501#define MMF_DUMP_ELF_HEADERS    6
502#define MMF_DUMP_HUGETLB_PRIVATE 7
503#define MMF_DUMP_HUGETLB_SHARED  8
504#define MMF_DUMP_DAX_PRIVATE    9
505#define MMF_DUMP_DAX_SHARED     10
506
507#define MMF_DUMP_FILTER_SHIFT   MMF_DUMPABLE_BITS
508#define MMF_DUMP_FILTER_BITS    9
509#define MMF_DUMP_FILTER_MASK \
510        (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
511#define MMF_DUMP_FILTER_DEFAULT \
512        ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
513         (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
514
515#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
516# define MMF_DUMP_MASK_DEFAULT_ELF      (1 << MMF_DUMP_ELF_HEADERS)
517#else
518# define MMF_DUMP_MASK_DEFAULT_ELF      0
519#endif
520                                        /* leave room for more dump flags */
521#define MMF_VM_MERGEABLE        16      /* KSM may merge identical pages */
522#define MMF_VM_HUGEPAGE         17      /* set when VM_HUGEPAGE is set on vma */
523#define MMF_EXE_FILE_CHANGED    18      /* see prctl_set_mm_exe_file() */
524
525#define MMF_HAS_UPROBES         19      /* has uprobes */
526#define MMF_RECALC_UPROBES      20      /* MMF_HAS_UPROBES can be wrong */
527#define MMF_OOM_SKIP            21      /* mm is of no interest for the OOM killer */
528#define MMF_UNSTABLE            22      /* mm is unstable for copy_from_user */
529#define MMF_HUGE_ZERO_PAGE      23      /* mm has ever used the global huge zero page */
530
531#define MMF_INIT_MASK           (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
532
533struct sighand_struct {
534        atomic_t                count;
535        struct k_sigaction      action[_NSIG];
536        spinlock_t              siglock;
537        wait_queue_head_t       signalfd_wqh;
538};
539
540struct pacct_struct {
541        int                     ac_flag;
542        long                    ac_exitcode;
543        unsigned long           ac_mem;
544        cputime_t               ac_utime, ac_stime;
545        unsigned long           ac_minflt, ac_majflt;
546};
547
548struct cpu_itimer {
549        cputime_t expires;
550        cputime_t incr;
551        u32 error;
552        u32 incr_error;
553};
554
555/**
556 * struct prev_cputime - snaphsot of system and user cputime
557 * @utime: time spent in user mode
558 * @stime: time spent in system mode
559 * @lock: protects the above two fields
560 *
561 * Stores previous user/system time values such that we can guarantee
562 * monotonicity.
563 */
564struct prev_cputime {
565#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
566        cputime_t utime;
567        cputime_t stime;
568        raw_spinlock_t lock;
569#endif
570};
571
572static inline void prev_cputime_init(struct prev_cputime *prev)
573{
574#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
575        prev->utime = prev->stime = 0;
576        raw_spin_lock_init(&prev->lock);
577#endif
578}
579
580/**
581 * struct task_cputime - collected CPU time counts
582 * @utime:              time spent in user mode, in &cputime_t units
583 * @stime:              time spent in kernel mode, in &cputime_t units
584 * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
585 *
586 * This structure groups together three kinds of CPU time that are tracked for
587 * threads and thread groups.  Most things considering CPU time want to group
588 * these counts together and treat all three of them in parallel.
589 */
590struct task_cputime {
591        cputime_t utime;
592        cputime_t stime;
593        unsigned long long sum_exec_runtime;
594};
595
596/* Alternate field names when used to cache expirations. */
597#define virt_exp        utime
598#define prof_exp        stime
599#define sched_exp       sum_exec_runtime
600
601#define INIT_CPUTIME    \
602        (struct task_cputime) {                                 \
603                .utime = 0,                                     \
604                .stime = 0,                                     \
605                .sum_exec_runtime = 0,                          \
606        }
607
608/*
609 * This is the atomic variant of task_cputime, which can be used for
610 * storing and updating task_cputime statistics without locking.
611 */
612struct task_cputime_atomic {
613        atomic64_t utime;
614        atomic64_t stime;
615        atomic64_t sum_exec_runtime;
616};
617
618#define INIT_CPUTIME_ATOMIC \
619        (struct task_cputime_atomic) {                          \
620                .utime = ATOMIC64_INIT(0),                      \
621                .stime = ATOMIC64_INIT(0),                      \
622                .sum_exec_runtime = ATOMIC64_INIT(0),           \
623        }
624
625#define PREEMPT_DISABLED        (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
626
627/*
628 * Disable preemption until the scheduler is running -- use an unconditional
629 * value so that it also works on !PREEMPT_COUNT kernels.
630 *
631 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
632 */
633#define INIT_PREEMPT_COUNT      PREEMPT_OFFSET
634
635/*
636 * Initial preempt_count value; reflects the preempt_count schedule invariant
637 * which states that during context switches:
638 *
639 *    preempt_count() == 2*PREEMPT_DISABLE_OFFSET
640 *
641 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
642 * Note: See finish_task_switch().
643 */
644#define FORK_PREEMPT_COUNT      (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
645
646/**
647 * struct thread_group_cputimer - thread group interval timer counts
648 * @cputime_atomic:     atomic thread group interval timers.
649 * @running:            true when there are timers running and
650 *                      @cputime_atomic receives updates.
651 * @checking_timer:     true when a thread in the group is in the
652 *                      process of checking for thread group timers.
653 *
654 * This structure contains the version of task_cputime, above, that is
655 * used for thread group CPU timer calculations.
656 */
657struct thread_group_cputimer {
658        struct task_cputime_atomic cputime_atomic;
659        bool running;
660        bool checking_timer;
661};
662
663#include <linux/rwsem.h>
664struct autogroup;
665
666/*
667 * NOTE! "signal_struct" does not have its own
668 * locking, because a shared signal_struct always
669 * implies a shared sighand_struct, so locking
670 * sighand_struct is always a proper superset of
671 * the locking of signal_struct.
672 */
673struct signal_struct {
674        atomic_t                sigcnt;
675        atomic_t                live;
676        int                     nr_threads;
677        struct list_head        thread_head;
678
679        wait_queue_head_t       wait_chldexit;  /* for wait4() */
680
681        /* current thread group signal load-balancing target: */
682        struct task_struct      *curr_target;
683
684        /* shared signal handling: */
685        struct sigpending       shared_pending;
686
687        /* thread group exit support */
688        int                     group_exit_code;
689        /* overloaded:
690         * - notify group_exit_task when ->count is equal to notify_count
691         * - everyone except group_exit_task is stopped during signal delivery
692         *   of fatal signals, group_exit_task processes the signal.
693         */
694        int                     notify_count;
695        struct task_struct      *group_exit_task;
696
697        /* thread group stop support, overloads group_exit_code too */
698        int                     group_stop_count;
699        unsigned int            flags; /* see SIGNAL_* flags below */
700
701        /*
702         * PR_SET_CHILD_SUBREAPER marks a process, like a service
703         * manager, to re-parent orphan (double-forking) child processes
704         * to this process instead of 'init'. The service manager is
705         * able to receive SIGCHLD signals and is able to investigate
706         * the process until it calls wait(). All children of this
707         * process will inherit a flag if they should look for a
708         * child_subreaper process at exit.
709         */
710        unsigned int            is_child_subreaper:1;
711        unsigned int            has_child_subreaper:1;
712
713        /* POSIX.1b Interval Timers */
714        int                     posix_timer_id;
715        struct list_head        posix_timers;
716
717        /* ITIMER_REAL timer for the process */
718        struct hrtimer real_timer;
719        struct pid *leader_pid;
720        ktime_t it_real_incr;
721
722        /*
723         * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
724         * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
725         * values are defined to 0 and 1 respectively
726         */
727        struct cpu_itimer it[2];
728
729        /*
730         * Thread group totals for process CPU timers.
731         * See thread_group_cputimer(), et al, for details.
732         */
733        struct thread_group_cputimer cputimer;
734
735        /* Earliest-expiration cache. */
736        struct task_cputime cputime_expires;
737
738#ifdef CONFIG_NO_HZ_FULL
739        atomic_t tick_dep_mask;
740#endif
741
742        struct list_head cpu_timers[3];
743
744        struct pid *tty_old_pgrp;
745
746        /* boolean value for session group leader */
747        int leader;
748
749        struct tty_struct *tty; /* NULL if no tty */
750
751#ifdef CONFIG_SCHED_AUTOGROUP
752        struct autogroup *autogroup;
753#endif
754        /*
755         * Cumulative resource counters for dead threads in the group,
756         * and for reaped dead child processes forked by this group.
757         * Live threads maintain their own counters and add to these
758         * in __exit_signal, except for the group leader.
759         */
760        seqlock_t stats_lock;
761        cputime_t utime, stime, cutime, cstime;
762        cputime_t gtime;
763        cputime_t cgtime;
764        struct prev_cputime prev_cputime;
765        unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
766        unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
767        unsigned long inblock, oublock, cinblock, coublock;
768        unsigned long maxrss, cmaxrss;
769        struct task_io_accounting ioac;
770
771        /*
772         * Cumulative ns of schedule CPU time fo dead threads in the
773         * group, not including a zombie group leader, (This only differs
774         * from jiffies_to_ns(utime + stime) if sched_clock uses something
775         * other than jiffies.)
776         */
777        unsigned long long sum_sched_runtime;
778
779        /*
780         * We don't bother to synchronize most readers of this at all,
781         * because there is no reader checking a limit that actually needs
782         * to get both rlim_cur and rlim_max atomically, and either one
783         * alone is a single word that can safely be read normally.
784         * getrlimit/setrlimit use task_lock(current->group_leader) to
785         * protect this instead of the siglock, because they really
786         * have no need to disable irqs.
787         */
788        struct rlimit rlim[RLIM_NLIMITS];
789
790#ifdef CONFIG_BSD_PROCESS_ACCT
791        struct pacct_struct pacct;      /* per-process accounting information */
792#endif
793#ifdef CONFIG_TASKSTATS
794        struct taskstats *stats;
795#endif
796#ifdef CONFIG_AUDIT
797        unsigned audit_tty;
798        struct tty_audit_buf *tty_audit_buf;
799#endif
800
801        /*
802         * Thread is the potential origin of an oom condition; kill first on
803         * oom
804         */
805        bool oom_flag_origin;
806        short oom_score_adj;            /* OOM kill score adjustment */
807        short oom_score_adj_min;        /* OOM kill score adjustment min value.
808                                         * Only settable by CAP_SYS_RESOURCE. */
809        struct mm_struct *oom_mm;       /* recorded mm when the thread group got
810                                         * killed by the oom killer */
811
812        struct mutex cred_guard_mutex;  /* guard against foreign influences on
813                                         * credential calculations
814                                         * (notably. ptrace) */
815};
816
817/*
818 * Bits in flags field of signal_struct.
819 */
820#define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
821#define SIGNAL_STOP_CONTINUED   0x00000002 /* SIGCONT since WCONTINUED reap */
822#define SIGNAL_GROUP_EXIT       0x00000004 /* group exit in progress */
823#define SIGNAL_GROUP_COREDUMP   0x00000008 /* coredump in progress */
824/*
825 * Pending notifications to parent.
826 */
827#define SIGNAL_CLD_STOPPED      0x00000010
828#define SIGNAL_CLD_CONTINUED    0x00000020
829#define SIGNAL_CLD_MASK         (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
830
831#define SIGNAL_UNKILLABLE       0x00000040 /* for init: ignore fatal signals */
832
833/* If true, all threads except ->group_exit_task have pending SIGKILL */
834static inline int signal_group_exit(const struct signal_struct *sig)
835{
836        return  (sig->flags & SIGNAL_GROUP_EXIT) ||
837                (sig->group_exit_task != NULL);
838}
839
840/*
841 * Some day this will be a full-fledged user tracking system..
842 */
843struct user_struct {
844        atomic_t __count;       /* reference count */
845        atomic_t processes;     /* How many processes does this user have? */
846        atomic_t sigpending;    /* How many pending signals does this user have? */
847#ifdef CONFIG_INOTIFY_USER
848        atomic_t inotify_watches; /* How many inotify watches does this user have? */
849        atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
850#endif
851#ifdef CONFIG_FANOTIFY
852        atomic_t fanotify_listeners;
853#endif
854#ifdef CONFIG_EPOLL
855        atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
856#endif
857#ifdef CONFIG_POSIX_MQUEUE
858        /* protected by mq_lock */
859        unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
860#endif
861        unsigned long locked_shm; /* How many pages of mlocked shm ? */
862        unsigned long unix_inflight;    /* How many files in flight in unix sockets */
863        atomic_long_t pipe_bufs;  /* how many pages are allocated in pipe buffers */
864
865#ifdef CONFIG_KEYS
866        struct key *uid_keyring;        /* UID specific keyring */
867        struct key *session_keyring;    /* UID's default session keyring */
868#endif
869
870        /* Hash table maintenance information */
871        struct hlist_node uidhash_node;
872        kuid_t uid;
873
874#if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
875        atomic_long_t locked_vm;
876#endif
877};
878
879extern int uids_sysfs_init(void);
880
881extern struct user_struct *find_user(kuid_t);
882
883extern struct user_struct root_user;
884#define INIT_USER (&root_user)
885
886
887struct backing_dev_info;
888struct reclaim_state;
889
890#ifdef CONFIG_SCHED_INFO
891struct sched_info {
892        /* cumulative counters */
893        unsigned long pcount;         /* # of times run on this cpu */
894        unsigned long long run_delay; /* time spent waiting on a runqueue */
895
896        /* timestamps */
897        unsigned long long last_arrival,/* when we last ran on a cpu */
898                           last_queued; /* when we were last queued to run */
899};
900#endif /* CONFIG_SCHED_INFO */
901
902#ifdef CONFIG_TASK_DELAY_ACCT
903struct task_delay_info {
904        spinlock_t      lock;
905        unsigned int    flags;  /* Private per-task flags */
906
907        /* For each stat XXX, add following, aligned appropriately
908         *
909         * struct timespec XXX_start, XXX_end;
910         * u64 XXX_delay;
911         * u32 XXX_count;
912         *
913         * Atomicity of updates to XXX_delay, XXX_count protected by
914         * single lock above (split into XXX_lock if contention is an issue).
915         */
916
917        /*
918         * XXX_count is incremented on every XXX operation, the delay
919         * associated with the operation is added to XXX_delay.
920         * XXX_delay contains the accumulated delay time in nanoseconds.
921         */
922        u64 blkio_start;        /* Shared by blkio, swapin */
923        u64 blkio_delay;        /* wait for sync block io completion */
924        u64 swapin_delay;       /* wait for swapin block io completion */
925        u32 blkio_count;        /* total count of the number of sync block */
926                                /* io operations performed */
927        u32 swapin_count;       /* total count of the number of swapin block */
928                                /* io operations performed */
929
930        u64 freepages_start;
931        u64 freepages_delay;    /* wait for memory reclaim */
932        u32 freepages_count;    /* total count of memory reclaim */
933};
934#endif  /* CONFIG_TASK_DELAY_ACCT */
935
936static inline int sched_info_on(void)
937{
938#ifdef CONFIG_SCHEDSTATS
939        return 1;
940#elif defined(CONFIG_TASK_DELAY_ACCT)
941        extern int delayacct_on;
942        return delayacct_on;
943#else
944        return 0;
945#endif
946}
947
948#ifdef CONFIG_SCHEDSTATS
949void force_schedstat_enabled(void);
950#endif
951
952enum cpu_idle_type {
953        CPU_IDLE,
954        CPU_NOT_IDLE,
955        CPU_NEWLY_IDLE,
956        CPU_MAX_IDLE_TYPES
957};
958
959/*
960 * Integer metrics need fixed point arithmetic, e.g., sched/fair
961 * has a few: load, load_avg, util_avg, freq, and capacity.
962 *
963 * We define a basic fixed point arithmetic range, and then formalize
964 * all these metrics based on that basic range.
965 */
966# define SCHED_FIXEDPOINT_SHIFT 10
967# define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
968
969/*
970 * Increase resolution of cpu_capacity calculations
971 */
972#define SCHED_CAPACITY_SHIFT    SCHED_FIXEDPOINT_SHIFT
973#define SCHED_CAPACITY_SCALE    (1L << SCHED_CAPACITY_SHIFT)
974
975/*
976 * Wake-queues are lists of tasks with a pending wakeup, whose
977 * callers have already marked the task as woken internally,
978 * and can thus carry on. A common use case is being able to
979 * do the wakeups once the corresponding user lock as been
980 * released.
981 *
982 * We hold reference to each task in the list across the wakeup,
983 * thus guaranteeing that the memory is still valid by the time
984 * the actual wakeups are performed in wake_up_q().
985 *
986 * One per task suffices, because there's never a need for a task to be
987 * in two wake queues simultaneously; it is forbidden to abandon a task
988 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
989 * already in a wake queue, the wakeup will happen soon and the second
990 * waker can just skip it.
991 *
992 * The WAKE_Q macro declares and initializes the list head.
993 * wake_up_q() does NOT reinitialize the list; it's expected to be
994 * called near the end of a function, where the fact that the queue is
995 * not used again will be easy to see by inspection.
996 *
997 * Note that this can cause spurious wakeups. schedule() callers
998 * must ensure the call is done inside a loop, confirming that the
999 * wakeup condition has in fact occurred.
1000 */
1001struct wake_q_node {
1002        struct wake_q_node *next;
1003};
1004
1005struct wake_q_head {
1006        struct wake_q_node *first;
1007        struct wake_q_node **lastp;
1008};
1009
1010#define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
1011
1012#define WAKE_Q(name)                                    \
1013        struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
1014
1015extern void wake_q_add(struct wake_q_head *head,
1016                       struct task_struct *task);
1017extern void wake_up_q(struct wake_q_head *head);
1018
1019/*
1020 * sched-domains (multiprocessor balancing) declarations:
1021 */
1022#ifdef CONFIG_SMP
1023#define SD_LOAD_BALANCE         0x0001  /* Do load balancing on this domain. */
1024#define SD_BALANCE_NEWIDLE      0x0002  /* Balance when about to become idle */
1025#define SD_BALANCE_EXEC         0x0004  /* Balance on exec */
1026#define SD_BALANCE_FORK         0x0008  /* Balance on fork, clone */
1027#define SD_BALANCE_WAKE         0x0010  /* Balance on wakeup */
1028#define SD_WAKE_AFFINE          0x0020  /* Wake task to waking CPU */
1029#define SD_ASYM_CPUCAPACITY     0x0040  /* Groups have different max cpu capacities */
1030#define SD_SHARE_CPUCAPACITY    0x0080  /* Domain members share cpu capacity */
1031#define SD_SHARE_POWERDOMAIN    0x0100  /* Domain members share power domain */
1032#define SD_SHARE_PKG_RESOURCES  0x0200  /* Domain members share cpu pkg resources */
1033#define SD_SERIALIZE            0x0400  /* Only a single load balancing instance */
1034#define SD_ASYM_PACKING         0x0800  /* Place busy groups earlier in the domain */
1035#define SD_PREFER_SIBLING       0x1000  /* Prefer to place tasks in a sibling domain */
1036#define SD_OVERLAP              0x2000  /* sched_domains of this level overlap */
1037#define SD_NUMA                 0x4000  /* cross-node balancing */
1038
1039#ifdef CONFIG_SCHED_SMT
1040static inline int cpu_smt_flags(void)
1041{
1042        return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
1043}
1044#endif
1045
1046#ifdef CONFIG_SCHED_MC
1047static inline int cpu_core_flags(void)
1048{
1049        return SD_SHARE_PKG_RESOURCES;
1050}
1051#endif
1052
1053#ifdef CONFIG_NUMA
1054static inline int cpu_numa_flags(void)
1055{
1056        return SD_NUMA;
1057}
1058#endif
1059
1060struct sched_domain_attr {
1061        int relax_domain_level;
1062};
1063
1064#define SD_ATTR_INIT    (struct sched_domain_attr) {    \
1065        .relax_domain_level = -1,                       \
1066}
1067
1068extern int sched_domain_level_max;
1069
1070struct sched_group;
1071
1072struct sched_domain_shared {
1073        atomic_t        ref;
1074        atomic_t        nr_busy_cpus;
1075        int             has_idle_cores;
1076};
1077
1078struct sched_domain {
1079        /* These fields must be setup */
1080        struct sched_domain *parent;    /* top domain must be null terminated */
1081        struct sched_domain *child;     /* bottom domain must be null terminated */
1082        struct sched_group *groups;     /* the balancing groups of the domain */
1083        unsigned long min_interval;     /* Minimum balance interval ms */
1084        unsigned long max_interval;     /* Maximum balance interval ms */
1085        unsigned int busy_factor;       /* less balancing by factor if busy */
1086        unsigned int imbalance_pct;     /* No balance until over watermark */
1087        unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
1088        unsigned int busy_idx;
1089        unsigned int idle_idx;
1090        unsigned int newidle_idx;
1091        unsigned int wake_idx;
1092        unsigned int forkexec_idx;
1093        unsigned int smt_gain;
1094
1095        int nohz_idle;                  /* NOHZ IDLE status */
1096        int flags;                      /* See SD_* */
1097        int level;
1098
1099        /* Runtime fields. */
1100        unsigned long last_balance;     /* init to jiffies. units in jiffies */
1101        unsigned int balance_interval;  /* initialise to 1. units in ms. */
1102        unsigned int nr_balance_failed; /* initialise to 0 */
1103
1104        /* idle_balance() stats */
1105        u64 max_newidle_lb_cost;
1106        unsigned long next_decay_max_lb_cost;
1107
1108        u64 avg_scan_cost;              /* select_idle_sibling */
1109
1110#ifdef CONFIG_SCHEDSTATS
1111        /* load_balance() stats */
1112        unsigned int lb_count[CPU_MAX_IDLE_TYPES];
1113        unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
1114        unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
1115        unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
1116        unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
1117        unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
1118        unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
1119        unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
1120
1121        /* Active load balancing */
1122        unsigned int alb_count;
1123        unsigned int alb_failed;
1124        unsigned int alb_pushed;
1125
1126        /* SD_BALANCE_EXEC stats */
1127        unsigned int sbe_count;
1128        unsigned int sbe_balanced;
1129        unsigned int sbe_pushed;
1130
1131        /* SD_BALANCE_FORK stats */
1132        unsigned int sbf_count;
1133        unsigned int sbf_balanced;
1134        unsigned int sbf_pushed;
1135
1136        /* try_to_wake_up() stats */
1137        unsigned int ttwu_wake_remote;
1138        unsigned int ttwu_move_affine;
1139        unsigned int ttwu_move_balance;
1140#endif
1141#ifdef CONFIG_SCHED_DEBUG
1142        char *name;
1143#endif
1144        union {
1145                void *private;          /* used during construction */
1146                struct rcu_head rcu;    /* used during destruction */
1147        };
1148        struct sched_domain_shared *shared;
1149
1150        unsigned int span_weight;
1151        /*
1152         * Span of all CPUs in this domain.
1153         *
1154         * NOTE: this field is variable length. (Allocated dynamically
1155         * by attaching extra space to the end of the structure,
1156         * depending on how many CPUs the kernel has booted up with)
1157         */
1158        unsigned long span[0];
1159};
1160
1161static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1162{
1163        return to_cpumask(sd->span);
1164}
1165
1166extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1167                                    struct sched_domain_attr *dattr_new);
1168
1169/* Allocate an array of sched domains, for partition_sched_domains(). */
1170cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1171void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1172
1173bool cpus_share_cache(int this_cpu, int that_cpu);
1174
1175typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
1176typedef int (*sched_domain_flags_f)(void);
1177
1178#define SDTL_OVERLAP    0x01
1179
1180struct sd_data {
1181        struct sched_domain **__percpu sd;
1182        struct sched_domain_shared **__percpu sds;
1183        struct sched_group **__percpu sg;
1184        struct sched_group_capacity **__percpu sgc;
1185};
1186
1187struct sched_domain_topology_level {
1188        sched_domain_mask_f mask;
1189        sched_domain_flags_f sd_flags;
1190        int                 flags;
1191        int                 numa_level;
1192        struct sd_data      data;
1193#ifdef CONFIG_SCHED_DEBUG
1194        char                *name;
1195#endif
1196};
1197
1198extern void set_sched_topology(struct sched_domain_topology_level *tl);
1199extern void wake_up_if_idle(int cpu);
1200
1201#ifdef CONFIG_SCHED_DEBUG
1202# define SD_INIT_NAME(type)             .name = #type
1203#else
1204# define SD_INIT_NAME(type)
1205#endif
1206
1207#else /* CONFIG_SMP */
1208
1209struct sched_domain_attr;
1210
1211static inline void
1212partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1213                        struct sched_domain_attr *dattr_new)
1214{
1215}
1216
1217static inline bool cpus_share_cache(int this_cpu, int that_cpu)
1218{
1219        return true;
1220}
1221
1222#endif  /* !CONFIG_SMP */
1223
1224
1225struct io_context;                      /* See blkdev.h */
1226
1227
1228#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1229extern void prefetch_stack(struct task_struct *t);
1230#else
1231static inline void prefetch_stack(struct task_struct *t) { }
1232#endif
1233
1234struct audit_context;           /* See audit.c */
1235struct mempolicy;
1236struct pipe_inode_info;
1237struct uts_namespace;
1238
1239struct load_weight {
1240        unsigned long weight;
1241        u32 inv_weight;
1242};
1243
1244/*
1245 * The load_avg/util_avg accumulates an infinite geometric series
1246 * (see __update_load_avg() in kernel/sched/fair.c).
1247 *
1248 * [load_avg definition]
1249 *
1250 *   load_avg = runnable% * scale_load_down(load)
1251 *
1252 * where runnable% is the time ratio that a sched_entity is runnable.
1253 * For cfs_rq, it is the aggregated load_avg of all runnable and
1254 * blocked sched_entities.
1255 *
1256 * load_avg may also take frequency scaling into account:
1257 *
1258 *   load_avg = runnable% * scale_load_down(load) * freq%
1259 *
1260 * where freq% is the CPU frequency normalized to the highest frequency.
1261 *
1262 * [util_avg definition]
1263 *
1264 *   util_avg = running% * SCHED_CAPACITY_SCALE
1265 *
1266 * where running% is the time ratio that a sched_entity is running on
1267 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
1268 * and blocked sched_entities.
1269 *
1270 * util_avg may also factor frequency scaling and CPU capacity scaling:
1271 *
1272 *   util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity%
1273 *
1274 * where freq% is the same as above, and capacity% is the CPU capacity
1275 * normalized to the greatest capacity (due to uarch differences, etc).
1276 *
1277 * N.B., the above ratios (runnable%, running%, freq%, and capacity%)
1278 * themselves are in the range of [0, 1]. To do fixed point arithmetics,
1279 * we therefore scale them to as large a range as necessary. This is for
1280 * example reflected by util_avg's SCHED_CAPACITY_SCALE.
1281 *
1282 * [Overflow issue]
1283 *
1284 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
1285 * with the highest load (=88761), always runnable on a single cfs_rq,
1286 * and should not overflow as the number already hits PID_MAX_LIMIT.
1287 *
1288 * For all other cases (including 32-bit kernels), struct load_weight's
1289 * weight will overflow first before we do, because:
1290 *
1291 *    Max(load_avg) <= Max(load.weight)
1292 *
1293 * Then it is the load_weight's responsibility to consider overflow
1294 * issues.
1295 */
1296struct sched_avg {
1297        u64 last_update_time, load_sum;
1298        u32 util_sum, period_contrib;
1299        unsigned long load_avg, util_avg;
1300};
1301
1302#ifdef CONFIG_SCHEDSTATS
1303struct sched_statistics {
1304        u64                     wait_start;
1305        u64                     wait_max;
1306        u64                     wait_count;
1307        u64                     wait_sum;
1308        u64                     iowait_count;
1309        u64                     iowait_sum;
1310
1311        u64                     sleep_start;
1312        u64                     sleep_max;
1313        s64                     sum_sleep_runtime;
1314
1315        u64                     block_start;
1316        u64                     block_max;
1317        u64                     exec_max;
1318        u64                     slice_max;
1319
1320        u64                     nr_migrations_cold;
1321        u64                     nr_failed_migrations_affine;
1322        u64                     nr_failed_migrations_running;
1323        u64                     nr_failed_migrations_hot;
1324        u64                     nr_forced_migrations;
1325
1326        u64                     nr_wakeups;
1327        u64                     nr_wakeups_sync;
1328        u64                     nr_wakeups_migrate;
1329        u64                     nr_wakeups_local;
1330        u64                     nr_wakeups_remote;
1331        u64                     nr_wakeups_affine;
1332        u64                     nr_wakeups_affine_attempts;
1333        u64                     nr_wakeups_passive;
1334        u64                     nr_wakeups_idle;
1335};
1336#endif
1337
1338struct sched_entity {
1339        struct load_weight      load;           /* for load-balancing */
1340        struct rb_node          run_node;
1341        struct list_head        group_node;
1342        unsigned int            on_rq;
1343
1344        u64                     exec_start;
1345        u64                     sum_exec_runtime;
1346        u64                     vruntime;
1347        u64                     prev_sum_exec_runtime;
1348
1349        u64                     nr_migrations;
1350
1351#ifdef CONFIG_SCHEDSTATS
1352        struct sched_statistics statistics;
1353#endif
1354
1355#ifdef CONFIG_FAIR_GROUP_SCHED
1356        int                     depth;
1357        struct sched_entity     *parent;
1358        /* rq on which this entity is (to be) queued: */
1359        struct cfs_rq           *cfs_rq;
1360        /* rq "owned" by this entity/group: */
1361        struct cfs_rq           *my_q;
1362#endif
1363
1364#ifdef CONFIG_SMP
1365        /*
1366         * Per entity load average tracking.
1367         *
1368         * Put into separate cache line so it does not
1369         * collide with read-mostly values above.
1370         */
1371        struct sched_avg        avg ____cacheline_aligned_in_smp;
1372#endif
1373};
1374
1375struct sched_rt_entity {
1376        struct list_head run_list;
1377        unsigned long timeout;
1378        unsigned long watchdog_stamp;
1379        unsigned int time_slice;
1380        unsigned short on_rq;
1381        unsigned short on_list;
1382
1383        struct sched_rt_entity *back;
1384#ifdef CONFIG_RT_GROUP_SCHED
1385        struct sched_rt_entity  *parent;
1386        /* rq on which this entity is (to be) queued: */
1387        struct rt_rq            *rt_rq;
1388        /* rq "owned" by this entity/group: */
1389        struct rt_rq            *my_q;
1390#endif
1391};
1392
1393struct sched_dl_entity {
1394        struct rb_node  rb_node;
1395
1396        /*
1397         * Original scheduling parameters. Copied here from sched_attr
1398         * during sched_setattr(), they will remain the same until
1399         * the next sched_setattr().
1400         */
1401        u64 dl_runtime;         /* maximum runtime for each instance    */
1402        u64 dl_deadline;        /* relative deadline of each instance   */
1403        u64 dl_period;          /* separation of two instances (period) */
1404        u64 dl_bw;              /* dl_runtime / dl_deadline             */
1405
1406        /*
1407         * Actual scheduling parameters. Initialized with the values above,
1408         * they are continously updated during task execution. Note that
1409         * the remaining runtime could be < 0 in case we are in overrun.
1410         */
1411        s64 runtime;            /* remaining runtime for this instance  */
1412        u64 deadline;           /* absolute deadline for this instance  */
1413        unsigned int flags;     /* specifying the scheduler behaviour   */
1414
1415        /*
1416         * Some bool flags:
1417         *
1418         * @dl_throttled tells if we exhausted the runtime. If so, the
1419         * task has to wait for a replenishment to be performed at the
1420         * next firing of dl_timer.
1421         *
1422         * @dl_boosted tells if we are boosted due to DI. If so we are
1423         * outside bandwidth enforcement mechanism (but only until we
1424         * exit the critical section);
1425         *
1426         * @dl_yielded tells if task gave up the cpu before consuming
1427         * all its available runtime during the last job.
1428         */
1429        int dl_throttled, dl_boosted, dl_yielded;
1430
1431        /*
1432         * Bandwidth enforcement timer. Each -deadline task has its
1433         * own bandwidth to be enforced, thus we need one timer per task.
1434         */
1435        struct hrtimer dl_timer;
1436};
1437
1438union rcu_special {
1439        struct {
1440                u8 blocked;
1441                u8 need_qs;
1442                u8 exp_need_qs;
1443                u8 pad; /* Otherwise the compiler can store garbage here. */
1444        } b; /* Bits. */
1445        u32 s; /* Set of bits. */
1446};
1447struct rcu_node;
1448
1449enum perf_event_task_context {
1450        perf_invalid_context = -1,
1451        perf_hw_context = 0,
1452        perf_sw_context,
1453        perf_nr_task_contexts,
1454};
1455
1456/* Track pages that require TLB flushes */
1457struct tlbflush_unmap_batch {
1458        /*
1459         * Each bit set is a CPU that potentially has a TLB entry for one of
1460         * the PFNs being flushed. See set_tlb_ubc_flush_pending().
1461         */
1462        struct cpumask cpumask;
1463
1464        /* True if any bit in cpumask is set */
1465        bool flush_required;
1466
1467        /*
1468         * If true then the PTE was dirty when unmapped. The entry must be
1469         * flushed before IO is initiated or a stale TLB entry potentially
1470         * allows an update without redirtying the page.
1471         */
1472        bool writable;
1473};
1474
1475struct task_struct {
1476#ifdef CONFIG_THREAD_INFO_IN_TASK
1477        /*
1478         * For reasons of header soup (see current_thread_info()), this
1479         * must be the first element of task_struct.
1480         */
1481        struct thread_info thread_info;
1482#endif
1483        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
1484        void *stack;
1485        atomic_t usage;
1486        unsigned int flags;     /* per process flags, defined below */
1487        unsigned int ptrace;
1488
1489#ifdef CONFIG_SMP
1490        struct llist_node wake_entry;
1491        int on_cpu;
1492#ifdef CONFIG_THREAD_INFO_IN_TASK
1493        unsigned int cpu;       /* current CPU */
1494#endif
1495        unsigned int wakee_flips;
1496        unsigned long wakee_flip_decay_ts;
1497        struct task_struct *last_wakee;
1498
1499        int wake_cpu;
1500#endif
1501        int on_rq;
1502
1503        int prio, static_prio, normal_prio;
1504        unsigned int rt_priority;
1505        const struct sched_class *sched_class;
1506        struct sched_entity se;
1507        struct sched_rt_entity rt;
1508#ifdef CONFIG_CGROUP_SCHED
1509        struct task_group *sched_task_group;
1510#endif
1511        struct sched_dl_entity dl;
1512
1513#ifdef CONFIG_PREEMPT_NOTIFIERS
1514        /* list of struct preempt_notifier: */
1515        struct hlist_head preempt_notifiers;
1516#endif
1517
1518#ifdef CONFIG_BLK_DEV_IO_TRACE
1519        unsigned int btrace_seq;
1520#endif
1521
1522        unsigned int policy;
1523        int nr_cpus_allowed;
1524        cpumask_t cpus_allowed;
1525
1526#ifdef CONFIG_PREEMPT_RCU
1527        int rcu_read_lock_nesting;
1528        union rcu_special rcu_read_unlock_special;
1529        struct list_head rcu_node_entry;
1530        struct rcu_node *rcu_blocked_node;
1531#endif /* #ifdef CONFIG_PREEMPT_RCU */
1532#ifdef CONFIG_TASKS_RCU
1533        unsigned long rcu_tasks_nvcsw;
1534        bool rcu_tasks_holdout;
1535        struct list_head rcu_tasks_holdout_list;
1536        int rcu_tasks_idle_cpu;
1537#endif /* #ifdef CONFIG_TASKS_RCU */
1538
1539#ifdef CONFIG_SCHED_INFO
1540        struct sched_info sched_info;
1541#endif
1542
1543        struct list_head tasks;
1544#ifdef CONFIG_SMP
1545        struct plist_node pushable_tasks;
1546        struct rb_node pushable_dl_tasks;
1547#endif
1548
1549        struct mm_struct *mm, *active_mm;
1550        /* per-thread vma caching */
1551        u32 vmacache_seqnum;
1552        struct vm_area_struct *vmacache[VMACACHE_SIZE];
1553#if defined(SPLIT_RSS_COUNTING)
1554        struct task_rss_stat    rss_stat;
1555#endif
1556/* task state */
1557        int exit_state;
1558        int exit_code, exit_signal;
1559        int pdeath_signal;  /*  The signal sent when the parent dies  */
1560        unsigned long jobctl;   /* JOBCTL_*, siglock protected */
1561
1562        /* Used for emulating ABI behavior of previous Linux versions */
1563        unsigned int personality;
1564
1565        /* scheduler bits, serialized by scheduler locks */
1566        unsigned sched_reset_on_fork:1;
1567        unsigned sched_contributes_to_load:1;
1568        unsigned sched_migrated:1;
1569        unsigned sched_remote_wakeup:1;
1570        unsigned :0; /* force alignment to the next boundary */
1571
1572        /* unserialized, strictly 'current' */
1573        unsigned in_execve:1; /* bit to tell LSMs we're in execve */
1574        unsigned in_iowait:1;
1575#if !defined(TIF_RESTORE_SIGMASK)
1576        unsigned restore_sigmask:1;
1577#endif
1578#ifdef CONFIG_MEMCG
1579        unsigned memcg_may_oom:1;
1580#ifndef CONFIG_SLOB
1581        unsigned memcg_kmem_skip_account:1;
1582#endif
1583#endif
1584#ifdef CONFIG_COMPAT_BRK
1585        unsigned brk_randomized:1;
1586#endif
1587#ifdef CONFIG_CGROUPS
1588        /* disallow userland-initiated cgroup migration */
1589        unsigned no_cgroup_migration:1;
1590#endif
1591
1592        unsigned long atomic_flags; /* Flags needing atomic access. */
1593
1594        struct restart_block restart_block;
1595
1596        pid_t pid;
1597        pid_t tgid;
1598
1599#ifdef CONFIG_CC_STACKPROTECTOR
1600        /* Canary value for the -fstack-protector gcc feature */
1601        unsigned long stack_canary;
1602#endif
1603        /*
1604         * pointers to (original) parent process, youngest child, younger sibling,
1605         * older sibling, respectively.  (p->father can be replaced with
1606         * p->real_parent->pid)
1607         */
1608        struct task_struct __rcu *real_parent; /* real parent process */
1609        struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1610        /*
1611         * children/sibling forms the list of my natural children
1612         */
1613        struct list_head children;      /* list of my children */
1614        struct list_head sibling;       /* linkage in my parent's children list */
1615        struct task_struct *group_leader;       /* threadgroup leader */
1616
1617        /*
1618         * ptraced is the list of tasks this task is using ptrace on.
1619         * This includes both natural children and PTRACE_ATTACH targets.
1620         * p->ptrace_entry is p's link on the p->parent->ptraced list.
1621         */
1622        struct list_head ptraced;
1623        struct list_head ptrace_entry;
1624
1625        /* PID/PID hash table linkage. */
1626        struct pid_link pids[PIDTYPE_MAX];
1627        struct list_head thread_group;
1628        struct list_head thread_node;
1629
1630        struct completion *vfork_done;          /* for vfork() */
1631        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
1632        int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
1633
1634        cputime_t utime, stime, utimescaled, stimescaled;
1635        cputime_t gtime;
1636        struct prev_cputime prev_cputime;
1637#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1638        seqcount_t vtime_seqcount;
1639        unsigned long long vtime_snap;
1640        enum {
1641                /* Task is sleeping or running in a CPU with VTIME inactive */
1642                VTIME_INACTIVE = 0,
1643                /* Task runs in userspace in a CPU with VTIME active */
1644                VTIME_USER,
1645                /* Task runs in kernelspace in a CPU with VTIME active */
1646                VTIME_SYS,
1647        } vtime_snap_whence;
1648#endif
1649
1650#ifdef CONFIG_NO_HZ_FULL
1651        atomic_t tick_dep_mask;
1652#endif
1653        unsigned long nvcsw, nivcsw; /* context switch counts */
1654        u64 start_time;         /* monotonic time in nsec */
1655        u64 real_start_time;    /* boot based time in nsec */
1656/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1657        unsigned long min_flt, maj_flt;
1658
1659        struct task_cputime cputime_expires;
1660        struct list_head cpu_timers[3];
1661
1662/* process credentials */
1663        const struct cred __rcu *ptracer_cred; /* Tracer's credentials at attach */
1664        const struct cred __rcu *real_cred; /* objective and real subjective task
1665                                         * credentials (COW) */
1666        const struct cred __rcu *cred;  /* effective (overridable) subjective task
1667                                         * credentials (COW) */
1668        char comm[TASK_COMM_LEN]; /* executable name excluding path
1669                                     - access with [gs]et_task_comm (which lock
1670                                       it with task_lock())
1671                                     - initialized normally by setup_new_exec */
1672/* file system info */
1673        struct nameidata *nameidata;
1674#ifdef CONFIG_SYSVIPC
1675/* ipc stuff */
1676        struct sysv_sem sysvsem;
1677        struct sysv_shm sysvshm;
1678#endif
1679#ifdef CONFIG_DETECT_HUNG_TASK
1680/* hung task detection */
1681        unsigned long last_switch_count;
1682#endif
1683/* filesystem information */
1684        struct fs_struct *fs;
1685/* open file information */
1686        struct files_struct *files;
1687/* namespaces */
1688        struct nsproxy *nsproxy;
1689/* signal handlers */
1690        struct signal_struct *signal;
1691        struct sighand_struct *sighand;
1692
1693        sigset_t blocked, real_blocked;
1694        sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1695        struct sigpending pending;
1696
1697        unsigned long sas_ss_sp;
1698        size_t sas_ss_size;
1699        unsigned sas_ss_flags;
1700
1701        struct callback_head *task_works;
1702
1703        struct audit_context *audit_context;
1704#ifdef CONFIG_AUDITSYSCALL
1705        kuid_t loginuid;
1706        unsigned int sessionid;
1707#endif
1708        struct seccomp seccomp;
1709
1710/* Thread group tracking */
1711        u32 parent_exec_id;
1712        u32 self_exec_id;
1713/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1714 * mempolicy */
1715        spinlock_t alloc_lock;
1716
1717        /* Protection of the PI data structures: */
1718        raw_spinlock_t pi_lock;
1719
1720        struct wake_q_node wake_q;
1721
1722#ifdef CONFIG_RT_MUTEXES
1723        /* PI waiters blocked on a rt_mutex held by this task */
1724        struct rb_root pi_waiters;
1725        struct rb_node *pi_waiters_leftmost;
1726        /* Deadlock detection and priority inheritance handling */
1727        struct rt_mutex_waiter *pi_blocked_on;
1728#endif
1729
1730#ifdef CONFIG_DEBUG_MUTEXES
1731        /* mutex deadlock detection */
1732        struct mutex_waiter *blocked_on;
1733#endif
1734#ifdef CONFIG_TRACE_IRQFLAGS
1735        unsigned int irq_events;
1736        unsigned long hardirq_enable_ip;
1737        unsigned long hardirq_disable_ip;
1738        unsigned int hardirq_enable_event;
1739        unsigned int hardirq_disable_event;
1740        int hardirqs_enabled;
1741        int hardirq_context;
1742        unsigned long softirq_disable_ip;
1743        unsigned long softirq_enable_ip;
1744        unsigned int softirq_disable_event;
1745        unsigned int softirq_enable_event;
1746        int softirqs_enabled;
1747        int softirq_context;
1748#endif
1749#ifdef CONFIG_LOCKDEP
1750# define MAX_LOCK_DEPTH 48UL
1751        u64 curr_chain_key;
1752        int lockdep_depth;
1753        unsigned int lockdep_recursion;
1754        struct held_lock held_locks[MAX_LOCK_DEPTH];
1755        gfp_t lockdep_reclaim_gfp;
1756#endif
1757#ifdef CONFIG_UBSAN
1758        unsigned int in_ubsan;
1759#endif
1760
1761/* journalling filesystem info */
1762        void *journal_info;
1763
1764/* stacked block device info */
1765        struct bio_list *bio_list;
1766
1767#ifdef CONFIG_BLOCK
1768/* stack plugging */
1769        struct blk_plug *plug;
1770#endif
1771
1772/* VM state */
1773        struct reclaim_state *reclaim_state;
1774
1775        struct backing_dev_info *backing_dev_info;
1776
1777        struct io_context *io_context;
1778
1779        unsigned long ptrace_message;
1780        siginfo_t *last_siginfo; /* For ptrace use.  */
1781        struct task_io_accounting ioac;
1782#if defined(CONFIG_TASK_XACCT)
1783        u64 acct_rss_mem1;      /* accumulated rss usage */
1784        u64 acct_vm_mem1;       /* accumulated virtual memory usage */
1785        cputime_t acct_timexpd; /* stime + utime since last update */
1786#endif
1787#ifdef CONFIG_CPUSETS
1788        nodemask_t mems_allowed;        /* Protected by alloc_lock */
1789        seqcount_t mems_allowed_seq;    /* Seqence no to catch updates */
1790        int cpuset_mem_spread_rotor;
1791        int cpuset_slab_spread_rotor;
1792#endif
1793#ifdef CONFIG_CGROUPS
1794        /* Control Group info protected by css_set_lock */
1795        struct css_set __rcu *cgroups;
1796        /* cg_list protected by css_set_lock and tsk->alloc_lock */
1797        struct list_head cg_list;
1798#endif
1799#ifdef CONFIG_FUTEX
1800        struct robust_list_head __user *robust_list;
1801#ifdef CONFIG_COMPAT
1802        struct compat_robust_list_head __user *compat_robust_list;
1803#endif
1804        struct list_head pi_state_list;
1805        struct futex_pi_state *pi_state_cache;
1806#endif
1807#ifdef CONFIG_PERF_EVENTS
1808        struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1809        struct mutex perf_event_mutex;
1810        struct list_head perf_event_list;
1811#endif
1812#ifdef CONFIG_DEBUG_PREEMPT
1813        unsigned long preempt_disable_ip;
1814#endif
1815#ifdef CONFIG_NUMA
1816        struct mempolicy *mempolicy;    /* Protected by alloc_lock */
1817        short il_next;
1818        short pref_node_fork;
1819#endif
1820#ifdef CONFIG_NUMA_BALANCING
1821        int numa_scan_seq;
1822        unsigned int numa_scan_period;
1823        unsigned int numa_scan_period_max;
1824        int numa_preferred_nid;
1825        unsigned long numa_migrate_retry;
1826        u64 node_stamp;                 /* migration stamp  */
1827        u64 last_task_numa_placement;
1828        u64 last_sum_exec_runtime;
1829        struct callback_head numa_work;
1830
1831        struct list_head numa_entry;
1832        struct numa_group *numa_group;
1833
1834        /*
1835         * numa_faults is an array split into four regions:
1836         * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1837         * in this precise order.
1838         *
1839         * faults_memory: Exponential decaying average of faults on a per-node
1840         * basis. Scheduling placement decisions are made based on these
1841         * counts. The values remain static for the duration of a PTE scan.
1842         * faults_cpu: Track the nodes the process was running on when a NUMA
1843         * hinting fault was incurred.
1844         * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1845         * during the current scan window. When the scan completes, the counts
1846         * in faults_memory and faults_cpu decay and these values are copied.
1847         */
1848        unsigned long *numa_faults;
1849        unsigned long total_numa_faults;
1850
1851        /*
1852         * numa_faults_locality tracks if faults recorded during the last
1853         * scan window were remote/local or failed to migrate. The task scan
1854         * period is adapted based on the locality of the faults with different
1855         * weights depending on whether they were shared or private faults
1856         */
1857        unsigned long numa_faults_locality[3];
1858
1859        unsigned long numa_pages_migrated;
1860#endif /* CONFIG_NUMA_BALANCING */
1861
1862#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
1863        struct tlbflush_unmap_batch tlb_ubc;
1864#endif
1865
1866        struct rcu_head rcu;
1867
1868        /*
1869         * cache last used pipe for splice
1870         */
1871        struct pipe_inode_info *splice_pipe;
1872
1873        struct page_frag task_frag;
1874
1875#ifdef  CONFIG_TASK_DELAY_ACCT
1876        struct task_delay_info *delays;
1877#endif
1878#ifdef CONFIG_FAULT_INJECTION
1879        int make_it_fail;
1880#endif
1881        /*
1882         * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1883         * balance_dirty_pages() for some dirty throttling pause
1884         */
1885        int nr_dirtied;
1886        int nr_dirtied_pause;
1887        unsigned long dirty_paused_when; /* start of a write-and-pause period */
1888
1889#ifdef CONFIG_LATENCYTOP
1890        int latency_record_count;
1891        struct latency_record latency_record[LT_SAVECOUNT];
1892#endif
1893        /*
1894         * time slack values; these are used to round up poll() and
1895         * select() etc timeout values. These are in nanoseconds.
1896         */
1897        u64 timer_slack_ns;
1898        u64 default_timer_slack_ns;
1899
1900#ifdef CONFIG_KASAN
1901        unsigned int kasan_depth;
1902#endif
1903#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1904        /* Index of current stored address in ret_stack */
1905        int curr_ret_stack;
1906        /* Stack of return addresses for return function tracing */
1907        struct ftrace_ret_stack *ret_stack;
1908        /* time stamp for last schedule */
1909        unsigned long long ftrace_timestamp;
1910        /*
1911         * Number of functions that haven't been traced
1912         * because of depth overrun.
1913         */
1914        atomic_t trace_overrun;
1915        /* Pause for the tracing */
1916        atomic_t tracing_graph_pause;
1917#endif
1918#ifdef CONFIG_TRACING
1919        /* state flags for use by tracers */
1920        unsigned long trace;
1921        /* bitmask and counter of trace recursion */
1922        unsigned long trace_recursion;
1923#endif /* CONFIG_TRACING */
1924#ifdef CONFIG_KCOV
1925        /* Coverage collection mode enabled for this task (0 if disabled). */
1926        enum kcov_mode kcov_mode;
1927        /* Size of the kcov_area. */
1928        unsigned        kcov_size;
1929        /* Buffer for coverage collection. */
1930        void            *kcov_area;
1931        /* kcov desciptor wired with this task or NULL. */
1932        struct kcov     *kcov;
1933#endif
1934#ifdef CONFIG_MEMCG
1935        struct mem_cgroup *memcg_in_oom;
1936        gfp_t memcg_oom_gfp_mask;
1937        int memcg_oom_order;
1938
1939        /* number of pages to reclaim on returning to userland */
1940        unsigned int memcg_nr_pages_over_high;
1941#endif
1942#ifdef CONFIG_UPROBES
1943        struct uprobe_task *utask;
1944#endif
1945#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1946        unsigned int    sequential_io;
1947        unsigned int    sequential_io_avg;
1948#endif
1949#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1950        unsigned long   task_state_change;
1951#endif
1952        int pagefault_disabled;
1953#ifdef CONFIG_MMU
1954        struct task_struct *oom_reaper_list;
1955#endif
1956#ifdef CONFIG_VMAP_STACK
1957        struct vm_struct *stack_vm_area;
1958#endif
1959#ifdef CONFIG_THREAD_INFO_IN_TASK
1960        /* A live task holds one reference. */
1961        atomic_t stack_refcount;
1962#endif
1963/* CPU-specific state of this task */
1964        struct thread_struct thread;
1965/*
1966 * WARNING: on x86, 'thread_struct' contains a variable-sized
1967 * structure.  It *MUST* be at the end of 'task_struct'.
1968 *
1969 * Do not put anything below here!
1970 */
1971};
1972
1973#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
1974extern int arch_task_struct_size __read_mostly;
1975#else
1976# define arch_task_struct_size (sizeof(struct task_struct))
1977#endif
1978
1979#ifdef CONFIG_VMAP_STACK
1980static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
1981{
1982        return t->stack_vm_area;
1983}
1984#else
1985static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
1986{
1987        return NULL;
1988}
1989#endif
1990
1991/* Future-safe accessor for struct task_struct's cpus_allowed. */
1992#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1993
1994static inline int tsk_nr_cpus_allowed(struct task_struct *p)
1995{
1996        return p->nr_cpus_allowed;
1997}
1998
1999#define TNF_MIGRATED    0x01
2000#define TNF_NO_GROUP    0x02
2001#define TNF_SHARED      0x04
2002#define TNF_FAULT_LOCAL 0x08
2003#define TNF_MIGRATE_FAIL 0x10
2004
2005static inline bool in_vfork(struct task_struct *tsk)
2006{
2007        bool ret;
2008
2009        /*
2010         * need RCU to access ->real_parent if CLONE_VM was used along with
2011         * CLONE_PARENT.
2012         *
2013         * We check real_parent->mm == tsk->mm because CLONE_VFORK does not
2014         * imply CLONE_VM
2015         *
2016         * CLONE_VFORK can be used with CLONE_PARENT/CLONE_THREAD and thus
2017         * ->real_parent is not necessarily the task doing vfork(), so in
2018         * theory we can't rely on task_lock() if we want to dereference it.
2019         *
2020         * And in this case we can't trust the real_parent->mm == tsk->mm
2021         * check, it can be false negative. But we do not care, if init or
2022         * another oom-unkillable task does this it should blame itself.
2023         */
2024        rcu_read_lock();
2025        ret = tsk->vfork_done && tsk->real_parent->mm == tsk->mm;
2026        rcu_read_unlock();
2027
2028        return ret;
2029}
2030
2031#ifdef CONFIG_NUMA_BALANCING
2032extern void task_numa_fault(int last_node, int node, int pages, int flags);
2033extern pid_t task_numa_group_id(struct task_struct *p);
2034extern void set_numabalancing_state(bool enabled);
2035extern void task_numa_free(struct task_struct *p);
2036extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
2037                                        int src_nid, int dst_cpu);
2038#else
2039static inline void task_numa_fault(int last_node, int node, int pages,
2040                                   int flags)
2041{
2042}
2043static inline pid_t task_numa_group_id(struct task_struct *p)
2044{
2045        return 0;
2046}
2047static inline void set_numabalancing_state(bool enabled)
2048{
2049}
2050static inline void task_numa_free(struct task_struct *p)
2051{
2052}
2053static inline bool should_numa_migrate_memory(struct task_struct *p,
2054                                struct page *page, int src_nid, int dst_cpu)
2055{
2056        return true;
2057}
2058#endif
2059
2060static inline struct pid *task_pid(struct task_struct *task)
2061{
2062        return task->pids[PIDTYPE_PID].pid;
2063}
2064
2065static inline struct pid *task_tgid(struct task_struct *task)
2066{
2067        return task->group_leader->pids[PIDTYPE_PID].pid;
2068}
2069
2070/*
2071 * Without tasklist or rcu lock it is not safe to dereference
2072 * the result of task_pgrp/task_session even if task == current,
2073 * we can race with another thread doing sys_setsid/sys_setpgid.
2074 */
2075static inline struct pid *task_pgrp(struct task_struct *task)
2076{
2077        return task->group_leader->pids[PIDTYPE_PGID].pid;
2078}
2079
2080static inline struct pid *task_session(struct task_struct *task)
2081{
2082        return task->group_leader->pids[PIDTYPE_SID].pid;
2083}
2084
2085struct pid_namespace;
2086
2087/*
2088 * the helpers to get the task's different pids as they are seen
2089 * from various namespaces
2090 *
2091 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
2092 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
2093 *                     current.
2094 * task_xid_nr_ns()  : id seen from the ns specified;
2095 *
2096 * set_task_vxid()   : assigns a virtual id to a task;
2097 *
2098 * see also pid_nr() etc in include/linux/pid.h
2099 */
2100pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
2101                        struct pid_namespace *ns);
2102
2103static inline pid_t task_pid_nr(struct task_struct *tsk)
2104{
2105        return tsk->pid;
2106}
2107
2108static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
2109                                        struct pid_namespace *ns)
2110{
2111        return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
2112}
2113
2114static inline pid_t task_pid_vnr(struct task_struct *tsk)
2115{
2116        return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
2117}
2118
2119
2120static inline pid_t task_tgid_nr(struct task_struct *tsk)
2121{
2122        return tsk->tgid;
2123}
2124
2125pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
2126
2127static inline pid_t task_tgid_vnr(struct task_struct *tsk)
2128{
2129        return pid_vnr(task_tgid(tsk));
2130}
2131
2132
2133static inline int pid_alive(const struct task_struct *p);
2134static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
2135{
2136        pid_t pid = 0;
2137
2138        rcu_read_lock();
2139        if (pid_alive(tsk))
2140                pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
2141        rcu_read_unlock();
2142
2143        return pid;
2144}
2145
2146static inline pid_t task_ppid_nr(const struct task_struct *tsk)
2147{
2148        return task_ppid_nr_ns(tsk, &init_pid_ns);
2149}
2150
2151static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
2152                                        struct pid_namespace *ns)
2153{
2154        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
2155}
2156
2157static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
2158{
2159        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
2160}
2161
2162
2163static inline pid_t task_session_nr_ns(struct task_struct *tsk,
2164                                        struct pid_namespace *ns)
2165{
2166        return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
2167}
2168
2169static inline pid_t task_session_vnr(struct task_struct *tsk)
2170{
2171        return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
2172}
2173
2174/* obsolete, do not use */
2175static inline pid_t task_pgrp_nr(struct task_struct *tsk)
2176{
2177        return task_pgrp_nr_ns(tsk, &init_pid_ns);
2178}
2179
2180/**
2181 * pid_alive - check that a task structure is not stale
2182 * @p: Task structure to be checked.
2183 *
2184 * Test if a process is not yet dead (at most zombie state)
2185 * If pid_alive fails, then pointers within the task structure
2186 * can be stale and must not be dereferenced.
2187 *
2188 * Return: 1 if the process is alive. 0 otherwise.
2189 */
2190static inline int pid_alive(const struct task_struct *p)
2191{
2192        return p->pids[PIDTYPE_PID].pid != NULL;
2193}
2194
2195/**
2196 * is_global_init - check if a task structure is init. Since init
2197 * is free to have sub-threads we need to check tgid.
2198 * @tsk: Task structure to be checked.
2199 *
2200 * Check if a task structure is the first user space task the kernel created.
2201 *
2202 * Return: 1 if the task structure is init. 0 otherwise.
2203 */
2204static inline int is_global_init(struct task_struct *tsk)
2205{
2206        return task_tgid_nr(tsk) == 1;
2207}
2208
2209extern struct pid *cad_pid;
2210
2211extern void free_task(struct task_struct *tsk);
2212#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
2213
2214extern void __put_task_struct(struct task_struct *t);
2215
2216static inline void put_task_struct(struct task_struct *t)
2217{
2218        if (atomic_dec_and_test(&t->usage))
2219                __put_task_struct(t);
2220}
2221
2222struct task_struct *task_rcu_dereference(struct task_struct **ptask);
2223struct task_struct *try_get_task_struct(struct task_struct **ptask);
2224
2225#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
2226extern void task_cputime(struct task_struct *t,
2227                         cputime_t *utime, cputime_t *stime);
2228extern void task_cputime_scaled(struct task_struct *t,
2229                                cputime_t *utimescaled, cputime_t *stimescaled);
2230extern cputime_t task_gtime(struct task_struct *t);
2231#else
2232static inline void task_cputime(struct task_struct *t,
2233                                cputime_t *utime, cputime_t *stime)
2234{
2235        if (utime)
2236                *utime = t->utime;
2237        if (stime)
2238                *stime = t->stime;
2239}
2240
2241static inline void task_cputime_scaled(struct task_struct *t,
2242                                       cputime_t *utimescaled,
2243                                       cputime_t *stimescaled)
2244{
2245        if (utimescaled)
2246                *utimescaled = t->utimescaled;
2247        if (stimescaled)
2248                *stimescaled = t->stimescaled;
2249}
2250
2251static inline cputime_t task_gtime(struct task_struct *t)
2252{
2253        return t->gtime;
2254}
2255#endif
2256extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2257extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2258
2259/*
2260 * Per process flags
2261 */
2262#define PF_EXITING      0x00000004      /* getting shut down */
2263#define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
2264#define PF_VCPU         0x00000010      /* I'm a virtual CPU */
2265#define PF_WQ_WORKER    0x00000020      /* I'm a workqueue worker */
2266#define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
2267#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
2268#define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
2269#define PF_DUMPCORE     0x00000200      /* dumped core */
2270#define PF_SIGNALED     0x00000400      /* killed by a signal */
2271#define PF_MEMALLOC     0x00000800      /* Allocating memory */
2272#define PF_NPROC_EXCEEDED 0x00001000    /* set_user noticed that RLIMIT_NPROC was exceeded */
2273#define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
2274#define PF_USED_ASYNC   0x00004000      /* used async_schedule*(), used by module init */
2275#define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
2276#define PF_FROZEN       0x00010000      /* frozen for system suspend */
2277#define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
2278#define PF_KSWAPD       0x00040000      /* I am kswapd */
2279#define PF_MEMALLOC_NOIO 0x00080000     /* Allocating memory without IO involved */
2280#define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
2281#define PF_KTHREAD      0x00200000      /* I am a kernel thread */
2282#define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
2283#define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
2284#define PF_NO_SETAFFINITY 0x04000000    /* Userland is not allowed to meddle with cpus_allowed */
2285#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
2286#define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
2287#define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezable */
2288#define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
2289
2290/*
2291 * Only the _current_ task can read/write to tsk->flags, but other
2292 * tasks can access tsk->flags in readonly mode for example
2293 * with tsk_used_math (like during threaded core dumping).
2294 * There is however an exception to this rule during ptrace
2295 * or during fork: the ptracer task is allowed to write to the
2296 * child->flags of its traced child (same goes for fork, the parent
2297 * can write to the child->flags), because we're guaranteed the
2298 * child is not running and in turn not changing child->flags
2299 * at the same time the parent does it.
2300 */
2301#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
2302#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
2303#define clear_used_math() clear_stopped_child_used_math(current)
2304#define set_used_math() set_stopped_child_used_math(current)
2305#define conditional_stopped_child_used_math(condition, child) \
2306        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
2307#define conditional_used_math(condition) \
2308        conditional_stopped_child_used_math(condition, current)
2309#define copy_to_stopped_child_used_math(child) \
2310        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
2311/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
2312#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
2313#define used_math() tsk_used_math(current)
2314
2315/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
2316 * __GFP_FS is also cleared as it implies __GFP_IO.
2317 */
2318static inline gfp_t memalloc_noio_flags(gfp_t flags)
2319{
2320        if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2321                flags &= ~(__GFP_IO | __GFP_FS);
2322        return flags;
2323}
2324
2325static inline unsigned int memalloc_noio_save(void)
2326{
2327        unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
2328        current->flags |= PF_MEMALLOC_NOIO;
2329        return flags;
2330}
2331
2332static inline void memalloc_noio_restore(unsigned int flags)
2333{
2334        current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
2335}
2336
2337/* Per-process atomic flags. */
2338#define PFA_NO_NEW_PRIVS 0      /* May not gain new privileges. */
2339#define PFA_SPREAD_PAGE  1      /* Spread page cache over cpuset */
2340#define PFA_SPREAD_SLAB  2      /* Spread some slab caches over cpuset */
2341#define PFA_LMK_WAITING  3      /* Lowmemorykiller is waiting */
2342
2343
2344#define TASK_PFA_TEST(name, func)                                       \
2345        static inline bool task_##func(struct task_struct *p)           \
2346        { return test_bit(PFA_##name, &p->atomic_flags); }
2347#define TASK_PFA_SET(name, func)                                        \
2348        static inline void task_set_##func(struct task_struct *p)       \
2349        { set_bit(PFA_##name, &p->atomic_flags); }
2350#define TASK_PFA_CLEAR(name, func)                                      \
2351        static inline void task_clear_##func(struct task_struct *p)     \
2352        { clear_bit(PFA_##name, &p->atomic_flags); }
2353
2354TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
2355TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2356
2357TASK_PFA_TEST(SPREAD_PAGE, spread_page)
2358TASK_PFA_SET(SPREAD_PAGE, spread_page)
2359TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2360
2361TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2362TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2363TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2364
2365TASK_PFA_TEST(LMK_WAITING, lmk_waiting)
2366TASK_PFA_SET(LMK_WAITING, lmk_waiting)
2367
2368/*
2369 * task->jobctl flags
2370 */
2371#define JOBCTL_STOP_SIGMASK     0xffff  /* signr of the last group stop */
2372
2373#define JOBCTL_STOP_DEQUEUED_BIT 16     /* stop signal dequeued */
2374#define JOBCTL_STOP_PENDING_BIT 17      /* task should stop for group stop */
2375#define JOBCTL_STOP_CONSUME_BIT 18      /* consume group stop count */
2376#define JOBCTL_TRAP_STOP_BIT    19      /* trap for STOP */
2377#define JOBCTL_TRAP_NOTIFY_BIT  20      /* trap for NOTIFY */
2378#define JOBCTL_TRAPPING_BIT     21      /* switching to TRACED */
2379#define JOBCTL_LISTENING_BIT    22      /* ptracer is listening for events */
2380
2381#define JOBCTL_STOP_DEQUEUED    (1UL << JOBCTL_STOP_DEQUEUED_BIT)
2382#define JOBCTL_STOP_PENDING     (1UL << JOBCTL_STOP_PENDING_BIT)
2383#define JOBCTL_STOP_CONSUME     (1UL << JOBCTL_STOP_CONSUME_BIT)
2384#define JOBCTL_TRAP_STOP        (1UL << JOBCTL_TRAP_STOP_BIT)
2385#define JOBCTL_TRAP_NOTIFY      (1UL << JOBCTL_TRAP_NOTIFY_BIT)
2386#define JOBCTL_TRAPPING         (1UL << JOBCTL_TRAPPING_BIT)
2387#define JOBCTL_LISTENING        (1UL << JOBCTL_LISTENING_BIT)
2388
2389#define JOBCTL_TRAP_MASK        (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2390#define JOBCTL_PENDING_MASK     (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2391
2392extern bool task_set_jobctl_pending(struct task_struct *task,
2393                                    unsigned long mask);
2394extern void task_clear_jobctl_trapping(struct task_struct *task);
2395extern void task_clear_jobctl_pending(struct task_struct *task,
2396                                      unsigned long mask);
2397
2398static inline void rcu_copy_process(struct task_struct *p)
2399{
2400#ifdef CONFIG_PREEMPT_RCU
2401        p->rcu_read_lock_nesting = 0;
2402        p->rcu_read_unlock_special.s = 0;
2403        p->rcu_blocked_node = NULL;
2404        INIT_LIST_HEAD(&p->rcu_node_entry);
2405#endif /* #ifdef CONFIG_PREEMPT_RCU */
2406#ifdef CONFIG_TASKS_RCU
2407        p->rcu_tasks_holdout = false;
2408        INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2409        p->rcu_tasks_idle_cpu = -1;
2410#endif /* #ifdef CONFIG_TASKS_RCU */
2411}
2412
2413static inline void tsk_restore_flags(struct task_struct *task,
2414                                unsigned long orig_flags, unsigned long flags)
2415{
2416        task->flags &= ~flags;
2417        task->flags |= orig_flags & flags;
2418}
2419
2420extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2421                                     const struct cpumask *trial);
2422extern int task_can_attach(struct task_struct *p,
2423                           const struct cpumask *cs_cpus_allowed);
2424#ifdef CONFIG_SMP
2425extern void do_set_cpus_allowed(struct task_struct *p,
2426                               const struct cpumask *new_mask);
2427
2428extern int set_cpus_allowed_ptr(struct task_struct *p,
2429                                const struct cpumask *new_mask);
2430#else
2431static inline void do_set_cpus_allowed(struct task_struct *p,
2432                                      const struct cpumask *new_mask)
2433{
2434}
2435static inline int set_cpus_allowed_ptr(struct task_struct *p,
2436                                       const struct cpumask *new_mask)
2437{
2438        if (!cpumask_test_cpu(0, new_mask))
2439                return -EINVAL;
2440        return 0;
2441}
2442#endif
2443
2444#ifdef CONFIG_NO_HZ_COMMON
2445void calc_load_enter_idle(void);
2446void calc_load_exit_idle(void);
2447#else
2448static inline void calc_load_enter_idle(void) { }
2449static inline void calc_load_exit_idle(void) { }
2450#endif /* CONFIG_NO_HZ_COMMON */
2451
2452/*
2453 * Do not use outside of architecture code which knows its limitations.
2454 *
2455 * sched_clock() has no promise of monotonicity or bounded drift between
2456 * CPUs, use (which you should not) requires disabling IRQs.
2457 *
2458 * Please use one of the three interfaces below.
2459 */
2460extern unsigned long long notrace sched_clock(void);
2461/*
2462 * See the comment in kernel/sched/clock.c
2463 */
2464extern u64 running_clock(void);
2465extern u64 sched_clock_cpu(int cpu);
2466
2467
2468extern void sched_clock_init(void);
2469
2470#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2471static inline void sched_clock_tick(void)
2472{
2473}
2474
2475static inline void sched_clock_idle_sleep_event(void)
2476{
2477}
2478
2479static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2480{
2481}
2482
2483static inline u64 cpu_clock(int cpu)
2484{
2485        return sched_clock();
2486}
2487
2488static inline u64 local_clock(void)
2489{
2490        return sched_clock();
2491}
2492#else
2493/*
2494 * Architectures can set this to 1 if they have specified
2495 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2496 * but then during bootup it turns out that sched_clock()
2497 * is reliable after all:
2498 */
2499extern int sched_clock_stable(void);
2500extern void set_sched_clock_stable(void);
2501extern void clear_sched_clock_stable(void);
2502
2503extern void sched_clock_tick(void);
2504extern void sched_clock_idle_sleep_event(void);
2505extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2506
2507/*
2508 * As outlined in clock.c, provides a fast, high resolution, nanosecond
2509 * time source that is monotonic per cpu argument and has bounded drift
2510 * between cpus.
2511 *
2512 * ######################### BIG FAT WARNING ##########################
2513 * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can #
2514 * # go backwards !!                                                  #
2515 * ####################################################################
2516 */
2517static inline u64 cpu_clock(int cpu)
2518{
2519        return sched_clock_cpu(cpu);
2520}
2521
2522static inline u64 local_clock(void)
2523{
2524        return sched_clock_cpu(raw_smp_processor_id());
2525}
2526#endif
2527
2528#ifdef CONFIG_IRQ_TIME_ACCOUNTING
2529/*
2530 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2531 * The reason for this explicit opt-in is not to have perf penalty with
2532 * slow sched_clocks.
2533 */
2534extern void enable_sched_clock_irqtime(void);
2535extern void disable_sched_clock_irqtime(void);
2536#else
2537static inline void enable_sched_clock_irqtime(void) {}
2538static inline void disable_sched_clock_irqtime(void) {}
2539#endif
2540
2541extern unsigned long long
2542task_sched_runtime(struct task_struct *task);
2543
2544/* sched_exec is called by processes performing an exec */
2545#ifdef CONFIG_SMP
2546extern void sched_exec(void);
2547#else
2548#define sched_exec()   {}
2549#endif
2550
2551extern void sched_clock_idle_sleep_event(void);
2552extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2553
2554#ifdef CONFIG_HOTPLUG_CPU
2555extern void idle_task_exit(void);
2556#else
2557static inline void idle_task_exit(void) {}
2558#endif
2559
2560#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2561extern void wake_up_nohz_cpu(int cpu);
2562#else
2563static inline void wake_up_nohz_cpu(int cpu) { }
2564#endif
2565
2566#ifdef CONFIG_NO_HZ_FULL
2567extern u64 scheduler_tick_max_deferment(void);
2568#endif
2569
2570#ifdef CONFIG_SCHED_AUTOGROUP
2571extern void sched_autogroup_create_attach(struct task_struct *p);
2572extern void sched_autogroup_detach(struct task_struct *p);
2573extern void sched_autogroup_fork(struct signal_struct *sig);
2574extern void sched_autogroup_exit(struct signal_struct *sig);
2575extern void sched_autogroup_exit_task(struct task_struct *p);
2576#ifdef CONFIG_PROC_FS
2577extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2578extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2579#endif
2580#else
2581static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2582static inline void sched_autogroup_detach(struct task_struct *p) { }
2583static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2584static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2585static inline void sched_autogroup_exit_task(struct task_struct *p) { }
2586#endif
2587
2588extern int yield_to(struct task_struct *p, bool preempt);
2589extern void set_user_nice(struct task_struct *p, long nice);
2590extern int task_prio(const struct task_struct *p);
2591/**
2592 * task_nice - return the nice value of a given task.
2593 * @p: the task in question.
2594 *
2595 * Return: The nice value [ -20 ... 0 ... 19 ].
2596 */
2597static inline int task_nice(const struct task_struct *p)
2598{
2599        return PRIO_TO_NICE((p)->static_prio);
2600}
2601extern int can_nice(const struct task_struct *p, const int nice);
2602extern int task_curr(const struct task_struct *p);
2603extern int idle_cpu(int cpu);
2604extern int sched_setscheduler(struct task_struct *, int,
2605                              const struct sched_param *);
2606extern int sched_setscheduler_nocheck(struct task_struct *, int,
2607                                      const struct sched_param *);
2608extern int sched_setattr(struct task_struct *,
2609                         const struct sched_attr *);
2610extern struct task_struct *idle_task(int cpu);
2611/**
2612 * is_idle_task - is the specified task an idle task?
2613 * @p: the task in question.
2614 *
2615 * Return: 1 if @p is an idle task. 0 otherwise.
2616 */
2617static inline bool is_idle_task(const struct task_struct *p)
2618{
2619        return p->pid == 0;
2620}
2621extern struct task_struct *curr_task(int cpu);
2622extern void ia64_set_curr_task(int cpu, struct task_struct *p);
2623
2624void yield(void);
2625
2626union thread_union {
2627#ifndef CONFIG_THREAD_INFO_IN_TASK
2628        struct thread_info thread_info;
2629#endif
2630        unsigned long stack[THREAD_SIZE/sizeof(long)];
2631};
2632
2633#ifndef __HAVE_ARCH_KSTACK_END
2634static inline int kstack_end(void *addr)
2635{
2636        /* Reliable end of stack detection:
2637         * Some APM bios versions misalign the stack
2638         */
2639        return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2640}
2641#endif
2642
2643extern union thread_union init_thread_union;
2644extern struct task_struct init_task;
2645
2646extern struct   mm_struct init_mm;
2647
2648extern struct pid_namespace init_pid_ns;
2649
2650/*
2651 * find a task by one of its numerical ids
2652 *
2653 * find_task_by_pid_ns():
2654 *      finds a task by its pid in the specified namespace
2655 * find_task_by_vpid():
2656 *      finds a task by its virtual pid
2657 *
2658 * see also find_vpid() etc in include/linux/pid.h
2659 */
2660
2661extern struct task_struct *find_task_by_vpid(pid_t nr);
2662extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2663                struct pid_namespace *ns);
2664
2665/* per-UID process charging. */
2666extern struct user_struct * alloc_uid(kuid_t);
2667static inline struct user_struct *get_uid(struct user_struct *u)
2668{
2669        atomic_inc(&u->__count);
2670        return u;
2671}
2672extern void free_uid(struct user_struct *);
2673
2674#include <asm/current.h>
2675
2676extern void xtime_update(unsigned long ticks);
2677
2678extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2679extern int wake_up_process(struct task_struct *tsk);
2680extern void wake_up_new_task(struct task_struct *tsk);
2681#ifdef CONFIG_SMP
2682 extern void kick_process(struct task_struct *tsk);
2683#else
2684 static inline void kick_process(struct task_struct *tsk) { }
2685#endif
2686extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2687extern void sched_dead(struct task_struct *p);
2688
2689extern void proc_caches_init(void);
2690extern void flush_signals(struct task_struct *);
2691extern void ignore_signals(struct task_struct *);
2692extern void flush_signal_handlers(struct task_struct *, int force_default);
2693extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2694
2695static inline int kernel_dequeue_signal(siginfo_t *info)
2696{
2697        struct task_struct *tsk = current;
2698        siginfo_t __info;
2699        int ret;
2700
2701        spin_lock_irq(&tsk->sighand->siglock);
2702        ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info);
2703        spin_unlock_irq(&tsk->sighand->siglock);
2704
2705        return ret;
2706}
2707
2708static inline void kernel_signal_stop(void)
2709{
2710        spin_lock_irq(&current->sighand->siglock);
2711        if (current->jobctl & JOBCTL_STOP_DEQUEUED)
2712                __set_current_state(TASK_STOPPED);
2713        spin_unlock_irq(&current->sighand->siglock);
2714
2715        schedule();
2716}
2717
2718extern void release_task(struct task_struct * p);
2719extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2720extern int force_sigsegv(int, struct task_struct *);
2721extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2722extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2723extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2724extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2725                                const struct cred *, u32);
2726extern int kill_pgrp(struct pid *pid, int sig, int priv);
2727extern int kill_pid(struct pid *pid, int sig, int priv);
2728extern int kill_proc_info(int, struct siginfo *, pid_t);
2729extern __must_check bool do_notify_parent(struct task_struct *, int);
2730extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2731extern void force_sig(int, struct task_struct *);
2732extern int send_sig(int, struct task_struct *, int);
2733extern int zap_other_threads(struct task_struct *p);
2734extern struct sigqueue *sigqueue_alloc(void);
2735extern void sigqueue_free(struct sigqueue *);
2736extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2737extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2738
2739#ifdef TIF_RESTORE_SIGMASK
2740/*
2741 * Legacy restore_sigmask accessors.  These are inefficient on
2742 * SMP architectures because they require atomic operations.
2743 */
2744
2745/**
2746 * set_restore_sigmask() - make sure saved_sigmask processing gets done
2747 *
2748 * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
2749 * will run before returning to user mode, to process the flag.  For
2750 * all callers, TIF_SIGPENDING is already set or it's no harm to set
2751 * it.  TIF_RESTORE_SIGMASK need not be in the set of bits that the
2752 * arch code will notice on return to user mode, in case those bits
2753 * are scarce.  We set TIF_SIGPENDING here to ensure that the arch
2754 * signal code always gets run when TIF_RESTORE_SIGMASK is set.
2755 */
2756static inline void set_restore_sigmask(void)
2757{
2758        set_thread_flag(TIF_RESTORE_SIGMASK);
2759        WARN_ON(!test_thread_flag(TIF_SIGPENDING));
2760}
2761static inline void clear_restore_sigmask(void)
2762{
2763        clear_thread_flag(TIF_RESTORE_SIGMASK);
2764}
2765static inline bool test_restore_sigmask(void)
2766{
2767        return test_thread_flag(TIF_RESTORE_SIGMASK);
2768}
2769static inline bool test_and_clear_restore_sigmask(void)
2770{
2771        return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
2772}
2773
2774#else   /* TIF_RESTORE_SIGMASK */
2775
2776/* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */
2777static inline void set_restore_sigmask(void)
2778{
2779        current->restore_sigmask = true;
2780        WARN_ON(!test_thread_flag(TIF_SIGPENDING));
2781}
2782static inline void clear_restore_sigmask(void)
2783{
2784        current->restore_sigmask = false;
2785}
2786static inline bool test_restore_sigmask(void)
2787{
2788        return current->restore_sigmask;
2789}
2790static inline bool test_and_clear_restore_sigmask(void)
2791{
2792        if (!current->restore_sigmask)
2793                return false;
2794        current->restore_sigmask = false;
2795        return true;
2796}
2797#endif
2798
2799static inline void restore_saved_sigmask(void)
2800{
2801        if (test_and_clear_restore_sigmask())
2802                __set_current_blocked(&current->saved_sigmask);
2803}
2804
2805static inline sigset_t *sigmask_to_save(void)
2806{
2807        sigset_t *res = &current->blocked;
2808        if (unlikely(test_restore_sigmask()))
2809                res = &current->saved_sigmask;
2810        return res;
2811}
2812
2813static inline int kill_cad_pid(int sig, int priv)
2814{
2815        return kill_pid(cad_pid, sig, priv);
2816}
2817
2818/* These can be the second arg to send_sig_info/send_group_sig_info.  */
2819#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2820#define SEND_SIG_PRIV   ((struct siginfo *) 1)
2821#define SEND_SIG_FORCED ((struct siginfo *) 2)
2822
2823/*
2824 * True if we are on the alternate signal stack.
2825 */
2826static inline int on_sig_stack(unsigned long sp)
2827{
2828        /*
2829         * If the signal stack is SS_AUTODISARM then, by construction, we
2830         * can't be on the signal stack unless user code deliberately set
2831         * SS_AUTODISARM when we were already on it.
2832         *
2833         * This improves reliability: if user state gets corrupted such that
2834         * the stack pointer points very close to the end of the signal stack,
2835         * then this check will enable the signal to be handled anyway.
2836         */
2837        if (current->sas_ss_flags & SS_AUTODISARM)
2838                return 0;
2839
2840#ifdef CONFIG_STACK_GROWSUP
2841        return sp >= current->sas_ss_sp &&
2842                sp - current->sas_ss_sp < current->sas_ss_size;
2843#else
2844        return sp > current->sas_ss_sp &&
2845                sp - current->sas_ss_sp <= current->sas_ss_size;
2846#endif
2847}
2848
2849static inline int sas_ss_flags(unsigned long sp)
2850{
2851        if (!current->sas_ss_size)
2852                return SS_DISABLE;
2853
2854        return on_sig_stack(sp) ? SS_ONSTACK : 0;
2855}
2856
2857static inline void sas_ss_reset(struct task_struct *p)
2858{
2859        p->sas_ss_sp = 0;
2860        p->sas_ss_size = 0;
2861        p->sas_ss_flags = SS_DISABLE;
2862}
2863
2864static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2865{
2866        if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2867#ifdef CONFIG_STACK_GROWSUP
2868                return current->sas_ss_sp;
2869#else
2870                return current->sas_ss_sp + current->sas_ss_size;
2871#endif
2872        return sp;
2873}
2874
2875/*
2876 * Routines for handling mm_structs
2877 */
2878extern struct mm_struct * mm_alloc(void);
2879
2880/* mmdrop drops the mm and the page tables */
2881extern void __mmdrop(struct mm_struct *);
2882static inline void mmdrop(struct mm_struct *mm)
2883{
2884        if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2885                __mmdrop(mm);
2886}
2887
2888static inline void mmdrop_async_fn(struct work_struct *work)
2889{
2890        struct mm_struct *mm = container_of(work, struct mm_struct, async_put_work);
2891        __mmdrop(mm);
2892}
2893
2894static inline void mmdrop_async(struct mm_struct *mm)
2895{
2896        if (unlikely(atomic_dec_and_test(&mm->mm_count))) {
2897                INIT_WORK(&mm->async_put_work, mmdrop_async_fn);
2898                schedule_work(&mm->async_put_work);
2899        }
2900}
2901
2902static inline bool mmget_not_zero(struct mm_struct *mm)
2903{
2904        return atomic_inc_not_zero(&mm->mm_users);
2905}
2906
2907/* mmput gets rid of the mappings and all user-space */
2908extern void mmput(struct mm_struct *);
2909#ifdef CONFIG_MMU
2910/* same as above but performs the slow path from the async context. Can
2911 * be called from the atomic context as well
2912 */
2913extern void mmput_async(struct mm_struct *);
2914#endif
2915
2916/* Grab a reference to a task's mm, if it is not already going away */
2917extern struct mm_struct *get_task_mm(struct task_struct *task);
2918/*
2919 * Grab a reference to a task's mm, if it is not already going away
2920 * and ptrace_may_access with the mode parameter passed to it
2921 * succeeds.
2922 */
2923extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2924/* Remove the current tasks stale references to the old mm_struct */
2925extern void mm_release(struct task_struct *, struct mm_struct *);
2926
2927#ifdef CONFIG_HAVE_COPY_THREAD_TLS
2928extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
2929                        struct task_struct *, unsigned long);
2930#else
2931extern int copy_thread(unsigned long, unsigned long, unsigned long,
2932                        struct task_struct *);
2933
2934/* Architectures that haven't opted into copy_thread_tls get the tls argument
2935 * via pt_regs, so ignore the tls argument passed via C. */
2936static inline int copy_thread_tls(
2937                unsigned long clone_flags, unsigned long sp, unsigned long arg,
2938                struct task_struct *p, unsigned long tls)
2939{
2940        return copy_thread(clone_flags, sp, arg, p);
2941}
2942#endif
2943extern void flush_thread(void);
2944
2945#ifdef CONFIG_HAVE_EXIT_THREAD
2946extern void exit_thread(struct task_struct *tsk);
2947#else
2948static inline void exit_thread(struct task_struct *tsk)
2949{
2950}
2951#endif
2952
2953extern void exit_files(struct task_struct *);
2954extern void __cleanup_sighand(struct sighand_struct *);
2955
2956extern void exit_itimers(struct signal_struct *);
2957extern void flush_itimer_signals(void);
2958
2959extern void do_group_exit(int);
2960
2961extern int do_execve(struct filename *,
2962                     const char __user * const __user *,
2963                     const char __user * const __user *);
2964extern int do_execveat(int, struct filename *,
2965                       const char __user * const __user *,
2966                       const char __user * const __user *,
2967                       int);
2968extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2969extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2970struct task_struct *fork_idle(int);
2971extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2972
2973extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2974static inline void set_task_comm(struct task_struct *tsk, const char *from)
2975{
2976        __set_task_comm(tsk, from, false);
2977}
2978extern char *get_task_comm(char *to, struct task_struct *tsk);
2979
2980#ifdef CONFIG_SMP
2981void scheduler_ipi(void);
2982extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2983#else
2984static inline void scheduler_ipi(void) { }
2985static inline unsigned long wait_task_inactive(struct task_struct *p,
2986                                               long match_state)
2987{
2988        return 1;
2989}
2990#endif
2991
2992#define tasklist_empty() \
2993        list_empty(&init_task.tasks)
2994
2995#define next_task(p) \
2996        list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2997
2998#define for_each_process(p) \
2999        for (p = &init_task ; (p = next_task(p)) != &init_task ; )
3000
3001extern bool current_is_single_threaded(void);
3002
3003/*
3004 * Careful: do_each_thread/while_each_thread is a double loop so
3005 *          'break' will not work as expected - use goto instead.
3006 */
3007#define do_each_thread(g, t) \
3008        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
3009
3010#define while_each_thread(g, t) \
3011        while ((t = next_thread(t)) != g)
3012
3013#define __for_each_thread(signal, t)    \
3014        list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
3015
3016#define for_each_thread(p, t)           \
3017        __for_each_thread((p)->signal, t)
3018
3019/* Careful: this is a double loop, 'break' won't work as expected. */
3020#define for_each_process_thread(p, t)   \
3021        for_each_process(p) for_each_thread(p, t)
3022
3023static inline int get_nr_threads(struct task_struct *tsk)
3024{
3025        return tsk->signal->nr_threads;
3026}
3027
3028static inline bool thread_group_leader(struct task_struct *p)
3029{
3030        return p->exit_signal >= 0;
3031}
3032
3033/* Do to the insanities of de_thread it is possible for a process
3034 * to have the pid of the thread group leader without actually being
3035 * the thread group leader.  For iteration through the pids in proc
3036 * all we care about is that we have a task with the appropriate
3037 * pid, we don't actually care if we have the right task.
3038 */
3039static inline bool has_group_leader_pid(struct task_struct *p)
3040{
3041        return task_pid(p) == p->signal->leader_pid;
3042}
3043
3044static inline
3045bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
3046{
3047        return p1->signal == p2->signal;
3048}
3049
3050static inline struct task_struct *next_thread(const struct task_struct *p)
3051{
3052        return list_entry_rcu(p->thread_group.next,
3053                              struct task_struct, thread_group);
3054}
3055
3056static inline int thread_group_empty(struct task_struct *p)
3057{
3058        return list_empty(&p->thread_group);
3059}
3060
3061#define delay_group_leader(p) \
3062                (thread_group_leader(p) && !thread_group_empty(p))
3063
3064/*
3065 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
3066 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
3067 * pins the final release of task.io_context.  Also protects ->cpuset and
3068 * ->cgroup.subsys[]. And ->vfork_done.
3069 *
3070 * Nests both inside and outside of read_lock(&tasklist_lock).
3071 * It must not be nested with write_lock_irq(&tasklist_lock),
3072 * neither inside nor outside.
3073 */
3074static inline void task_lock(struct task_struct *p)
3075{
3076        spin_lock(&p->alloc_lock);
3077}
3078
3079static inline void task_unlock(struct task_struct *p)
3080{
3081        spin_unlock(&p->alloc_lock);
3082}
3083
3084extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
3085                                                        unsigned long *flags);
3086
3087static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
3088                                                       unsigned long *flags)
3089{
3090        struct sighand_struct *ret;
3091
3092        ret = __lock_task_sighand(tsk, flags);
3093        (void)__cond_lock(&tsk->sighand->siglock, ret);
3094        return ret;
3095}
3096
3097static inline void unlock_task_sighand(struct task_struct *tsk,
3098                                                unsigned long *flags)
3099{
3100        spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
3101}
3102
3103/**
3104 * threadgroup_change_begin - mark the beginning of changes to a threadgroup
3105 * @tsk: task causing the changes
3106 *
3107 * All operations which modify a threadgroup - a new thread joining the
3108 * group, death of a member thread (the assertion of PF_EXITING) and
3109 * exec(2) dethreading the process and replacing the leader - are wrapped
3110 * by threadgroup_change_{begin|end}().  This is to provide a place which
3111 * subsystems needing threadgroup stability can hook into for
3112 * synchronization.
3113 */
3114static inline void threadgroup_change_begin(struct task_struct *tsk)
3115{
3116        might_sleep();
3117        cgroup_threadgroup_change_begin(tsk);
3118}
3119
3120/**
3121 * threadgroup_change_end - mark the end of changes to a threadgroup
3122 * @tsk: task causing the changes
3123 *
3124 * See threadgroup_change_begin().
3125 */
3126static inline void threadgroup_change_end(struct task_struct *tsk)
3127{
3128        cgroup_threadgroup_change_end(tsk);
3129}
3130
3131#ifdef CONFIG_THREAD_INFO_IN_TASK
3132
3133static inline struct thread_info *task_thread_info(struct task_struct *task)
3134{
3135        return &task->thread_info;
3136}
3137
3138/*
3139 * When accessing the stack of a non-current task that might exit, use
3140 * try_get_task_stack() instead.  task_stack_page will return a pointer
3141 * that could get freed out from under you.
3142 */
3143static inline void *task_stack_page(const struct task_struct *task)
3144{
3145        return task->stack;
3146}
3147
3148#define setup_thread_stack(new,old)     do { } while(0)
3149
3150static inline unsigned long *end_of_stack(const struct task_struct *task)
3151{
3152        return task->stack;
3153}
3154
3155#elif !defined(__HAVE_THREAD_FUNCTIONS)
3156
3157#define task_thread_info(task)  ((struct thread_info *)(task)->stack)
3158#define task_stack_page(task)   ((void *)(task)->stack)
3159
3160static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
3161{
3162        *task_thread_info(p) = *task_thread_info(org);
3163        task_thread_info(p)->task = p;
3164}
3165
3166/*
3167 * Return the address of the last usable long on the stack.
3168 *
3169 * When the stack grows down, this is just above the thread
3170 * info struct. Going any lower will corrupt the threadinfo.
3171 *
3172 * When the stack grows up, this is the highest address.
3173 * Beyond that position, we corrupt data on the next page.
3174 */
3175static inline unsigned long *end_of_stack(struct task_struct *p)
3176{
3177#ifdef CONFIG_STACK_GROWSUP
3178        return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
3179#else
3180        return (unsigned long *)(task_thread_info(p) + 1);
3181#endif
3182}
3183
3184#endif
3185
3186#ifdef CONFIG_THREAD_INFO_IN_TASK
3187static inline void *try_get_task_stack(struct task_struct *tsk)
3188{
3189        return atomic_inc_not_zero(&tsk->stack_refcount) ?
3190                task_stack_page(tsk) : NULL;
3191}
3192
3193extern void put_task_stack(struct task_struct *tsk);
3194#else
3195static inline void *try_get_task_stack(struct task_struct *tsk)
3196{
3197        return task_stack_page(tsk);
3198}
3199
3200static inline void put_task_stack(struct task_struct *tsk) {}
3201#endif
3202
3203#define task_stack_end_corrupted(task) \
3204                (*(end_of_stack(task)) != STACK_END_MAGIC)
3205
3206static inline int object_is_on_stack(void *obj)
3207{
3208        void *stack = task_stack_page(current);
3209
3210        return (obj >= stack) && (obj < (stack + THREAD_SIZE));
3211}
3212
3213extern void thread_stack_cache_init(void);
3214
3215#ifdef CONFIG_DEBUG_STACK_USAGE
3216static inline unsigned long stack_not_used(struct task_struct *p)
3217{
3218        unsigned long *n = end_of_stack(p);
3219
3220        do {    /* Skip over canary */
3221# ifdef CONFIG_STACK_GROWSUP
3222                n--;
3223# else
3224                n++;
3225# endif
3226        } while (!*n);
3227
3228# ifdef CONFIG_STACK_GROWSUP
3229        return (unsigned long)end_of_stack(p) - (unsigned long)n;
3230# else
3231        return (unsigned long)n - (unsigned long)end_of_stack(p);
3232# endif
3233}
3234#endif
3235extern void set_task_stack_end_magic(struct task_struct *tsk);
3236
3237/* set thread flags in other task's structures
3238 * - see asm/thread_info.h for TIF_xxxx flags available
3239 */
3240static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
3241{
3242        set_ti_thread_flag(task_thread_info(tsk), flag);
3243}
3244
3245static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
3246{
3247        clear_ti_thread_flag(task_thread_info(tsk), flag);
3248}
3249
3250static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
3251{
3252        return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
3253}
3254
3255static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
3256{
3257        return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
3258}
3259
3260static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
3261{
3262        return test_ti_thread_flag(task_thread_info(tsk), flag);
3263}
3264
3265static inline void set_tsk_need_resched(struct task_struct *tsk)
3266{
3267        set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
3268}
3269
3270static inline void clear_tsk_need_resched(struct task_struct *tsk)
3271{
3272        clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
3273}
3274
3275static inline int test_tsk_need_resched(struct task_struct *tsk)
3276{
3277        return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
3278}
3279
3280static inline int restart_syscall(void)
3281{
3282        set_tsk_thread_flag(current, TIF_SIGPENDING);
3283        return -ERESTARTNOINTR;
3284}
3285
3286static inline int signal_pending(struct task_struct *p)
3287{
3288        return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
3289}
3290
3291static inline int __fatal_signal_pending(struct task_struct *p)
3292{
3293        return unlikely(sigismember(&p->pending.signal, SIGKILL));
3294}
3295
3296static inline int fatal_signal_pending(struct task_struct *p)
3297{
3298        return signal_pending(p) && __fatal_signal_pending(p);
3299}
3300
3301static inline int signal_pending_state(long state, struct task_struct *p)
3302{
3303        if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
3304                return 0;
3305        if (!signal_pending(p))
3306                return 0;
3307
3308        return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
3309}
3310
3311/*
3312 * cond_resched() and cond_resched_lock(): latency reduction via
3313 * explicit rescheduling in places that are safe. The return
3314 * value indicates whether a reschedule was done in fact.
3315 * cond_resched_lock() will drop the spinlock before scheduling,
3316 * cond_resched_softirq() will enable bhs before scheduling.
3317 */
3318#ifndef CONFIG_PREEMPT
3319extern int _cond_resched(void);
3320#else
3321static inline int _cond_resched(void) { return 0; }
3322#endif
3323
3324#define cond_resched() ({                       \
3325        ___might_sleep(__FILE__, __LINE__, 0);  \
3326        _cond_resched();                        \
3327})
3328
3329extern int __cond_resched_lock(spinlock_t *lock);
3330
3331#define cond_resched_lock(lock) ({                              \
3332        ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
3333        __cond_resched_lock(lock);                              \
3334})
3335
3336extern int __cond_resched_softirq(void);
3337
3338#define cond_resched_softirq() ({                                       \
3339        ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);     \
3340        __cond_resched_softirq();                                       \
3341})
3342
3343static inline void cond_resched_rcu(void)
3344{
3345#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
3346        rcu_read_unlock();
3347        cond_resched();
3348        rcu_read_lock();
3349#endif
3350}
3351
3352static inline unsigned long get_preempt_disable_ip(struct task_struct *p)
3353{
3354#ifdef CONFIG_DEBUG_PREEMPT
3355        return p->preempt_disable_ip;
3356#else
3357        return 0;
3358#endif
3359}
3360
3361/*
3362 * Does a critical section need to be broken due to another
3363 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
3364 * but a general need for low latency)
3365 */
3366static inline int spin_needbreak(spinlock_t *lock)
3367{
3368#ifdef CONFIG_PREEMPT
3369        return spin_is_contended(lock);
3370#else
3371        return 0;
3372#endif
3373}
3374
3375/*
3376 * Idle thread specific functions to determine the need_resched
3377 * polling state.
3378 */
3379#ifdef TIF_POLLING_NRFLAG
3380static inline int tsk_is_polling(struct task_struct *p)
3381{
3382        return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
3383}
3384
3385static inline void __current_set_polling(void)
3386{
3387        set_thread_flag(TIF_POLLING_NRFLAG);
3388}
3389
3390static inline bool __must_check current_set_polling_and_test(void)
3391{
3392        __current_set_polling();
3393
3394        /*
3395         * Polling state must be visible before we test NEED_RESCHED,
3396         * paired by resched_curr()
3397         */
3398        smp_mb__after_atomic();
3399
3400        return unlikely(tif_need_resched());
3401}
3402
3403static inline void __current_clr_polling(void)
3404{
3405        clear_thread_flag(TIF_POLLING_NRFLAG);
3406}
3407
3408static inline bool __must_check current_clr_polling_and_test(void)
3409{
3410        __current_clr_polling();
3411
3412        /*
3413         * Polling state must be visible before we test NEED_RESCHED,
3414         * paired by resched_curr()
3415         */
3416        smp_mb__after_atomic();
3417
3418        return unlikely(tif_need_resched());
3419}
3420
3421#else
3422static inline int tsk_is_polling(struct task_struct *p) { return 0; }
3423static inline void __current_set_polling(void) { }
3424static inline void __current_clr_polling(void) { }
3425
3426static inline bool __must_check current_set_polling_and_test(void)
3427{
3428        return unlikely(tif_need_resched());
3429}
3430static inline bool __must_check current_clr_polling_and_test(void)
3431{
3432        return unlikely(tif_need_resched());
3433}
3434#endif
3435
3436static inline void current_clr_polling(void)
3437{
3438        __current_clr_polling();
3439
3440        /*
3441         * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
3442         * Once the bit is cleared, we'll get IPIs with every new
3443         * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
3444         * fold.
3445         */
3446        smp_mb(); /* paired with resched_curr() */
3447
3448        preempt_fold_need_resched();
3449}
3450
3451static __always_inline bool need_resched(void)
3452{
3453        return unlikely(tif_need_resched());
3454}
3455
3456/*
3457 * Thread group CPU time accounting.
3458 */
3459void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
3460void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
3461
3462/*
3463 * Reevaluate whether the task has signals pending delivery.
3464 * Wake the task if so.
3465 * This is required every time the blocked sigset_t changes.
3466 * callers must hold sighand->siglock.
3467 */
3468extern void recalc_sigpending_and_wake(struct task_struct *t);
3469extern void recalc_sigpending(void);
3470
3471extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
3472
3473static inline void signal_wake_up(struct task_struct *t, bool resume)
3474{
3475        signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
3476}
3477static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
3478{
3479        signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
3480}
3481
3482/*
3483 * Wrappers for p->thread_info->cpu access. No-op on UP.
3484 */
3485#ifdef CONFIG_SMP
3486
3487static inline unsigned int task_cpu(const struct task_struct *p)
3488{
3489#ifdef CONFIG_THREAD_INFO_IN_TASK
3490        return p->cpu;
3491#else
3492        return task_thread_info(p)->cpu;
3493#endif
3494}
3495
3496static inline int task_node(const struct task_struct *p)
3497{
3498        return cpu_to_node(task_cpu(p));
3499}
3500
3501extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
3502
3503#else
3504
3505static inline unsigned int task_cpu(const struct task_struct *p)
3506{
3507        return 0;
3508}
3509
3510static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
3511{
3512}
3513
3514#endif /* CONFIG_SMP */
3515
3516extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3517extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3518
3519#ifdef CONFIG_CGROUP_SCHED
3520extern struct task_group root_task_group;
3521#endif /* CONFIG_CGROUP_SCHED */
3522
3523extern int task_can_switch_user(struct user_struct *up,
3524                                        struct task_struct *tsk);
3525
3526#ifdef CONFIG_TASK_XACCT
3527static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3528{
3529        tsk->ioac.rchar += amt;
3530}
3531
3532static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3533{
3534        tsk->ioac.wchar += amt;
3535}
3536
3537static inline void inc_syscr(struct task_struct *tsk)
3538{
3539        tsk->ioac.syscr++;
3540}
3541
3542static inline void inc_syscw(struct task_struct *tsk)
3543{
3544        tsk->ioac.syscw++;
3545}
3546#else
3547static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3548{
3549}
3550
3551static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3552{
3553}
3554
3555static inline void inc_syscr(struct task_struct *tsk)
3556{
3557}
3558
3559static inline void inc_syscw(struct task_struct *tsk)
3560{
3561}
3562#endif
3563
3564#ifndef TASK_SIZE_OF
3565#define TASK_SIZE_OF(tsk)       TASK_SIZE
3566#endif
3567
3568#ifdef CONFIG_MEMCG
3569extern void mm_update_next_owner(struct mm_struct *mm);
3570#else
3571static inline void mm_update_next_owner(struct mm_struct *mm)
3572{
3573}
3574#endif /* CONFIG_MEMCG */
3575
3576static inline unsigned long task_rlimit(const struct task_struct *tsk,
3577                unsigned int limit)
3578{
3579        return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3580}
3581
3582static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3583                unsigned int limit)
3584{
3585        return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3586}
3587
3588static inline unsigned long rlimit(unsigned int limit)
3589{
3590        return task_rlimit(current, limit);
3591}
3592
3593static inline unsigned long rlimit_max(unsigned int limit)
3594{
3595        return task_rlimit_max(current, limit);
3596}
3597
3598#define SCHED_CPUFREQ_RT        (1U << 0)
3599#define SCHED_CPUFREQ_DL        (1U << 1)
3600#define SCHED_CPUFREQ_IOWAIT    (1U << 2)
3601
3602#define SCHED_CPUFREQ_RT_DL     (SCHED_CPUFREQ_RT | SCHED_CPUFREQ_DL)
3603
3604#ifdef CONFIG_CPU_FREQ
3605struct update_util_data {
3606       void (*func)(struct update_util_data *data, u64 time, unsigned int flags);
3607};
3608
3609void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
3610                       void (*func)(struct update_util_data *data, u64 time,
3611                                    unsigned int flags));
3612void cpufreq_remove_update_util_hook(int cpu);
3613#endif /* CONFIG_CPU_FREQ */
3614
3615#endif
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