1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3
4 #include <asm/param.h> /* for HZ */
5
6 #include <linux/config.h>
7 #include <linux/capability.h>
8 #include <linux/threads.h>
9 #include <linux/kernel.h>
10 #include <linux/types.h>
11 #include <linux/timex.h>
12 #include <linux/jiffies.h>
13 #include <linux/rbtree.h>
14 #include <linux/thread_info.h>
15 #include <linux/cpumask.h>
16 #include <linux/errno.h>
17
18 #include <asm/system.h>
19 #include <asm/semaphore.h>
20 #include <asm/page.h>
21 #include <asm/ptrace.h>
22 #include <asm/mmu.h>
23 #include <asm/cputime.h>
24
25 #include <linux/smp.h>
26 #include <linux/sem.h>
27 #include <linux/signal.h>
28 #include <linux/securebits.h>
29 #include <linux/fs_struct.h>
30 #include <linux/compiler.h>
31 #include <linux/completion.h>
32 #include <linux/pid.h>
33 #include <linux/percpu.h>
34 #include <linux/topology.h>
35
36 struct exec_domain;
37
38 /*
39 * cloning flags:
40 */
41 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
42 #define CLONE_VM 0x00000100 /* set if VM shared between processes */
43 #define CLONE_FS 0x00000200 /* set if fs info shared between processes */
44 #define CLONE_FILES 0x00000400 /* set if open files shared between processes */
45 #define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
46 #define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
47 #define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
48 #define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
49 #define CLONE_THREAD 0x00010000 /* Same thread group? */
50 #define CLONE_NEWNS 0x00020000 /* New namespace group? */
51 #define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
52 #define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
53 #define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */
54 #define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */
55 #define CLONE_DETACHED 0x00400000 /* Unused, ignored */
56 #define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
57 #define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */
58 #define CLONE_STOPPED 0x02000000 /* Start in stopped state */
59
60 /*
61 * List of flags we want to share for kernel threads,
62 * if only because they are not used by them anyway.
63 */
64 #define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
65
66 /*
67 * These are the constant used to fake the fixed-point load-average
68 * counting. Some notes:
69 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
70 * a load-average precision of 10 bits integer + 11 bits fractional
71 * - if you want to count load-averages more often, you need more
72 * precision, or rounding will get you. With 2-second counting freq,
73 * the EXP_n values would be 1981, 2034 and 2043 if still using only
74 * 11 bit fractions.
75 */
76 extern unsigned long avenrun[]; /* Load averages */
77
78 #define FSHIFT 11 /* nr of bits of precision */
79 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
80 #define LOAD_FREQ (5*HZ) /* 5 sec intervals */
81 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
82 #define EXP_5 2014 /* 1/exp(5sec/5min) */
83 #define EXP_15 2037 /* 1/exp(5sec/15min) */
84
85 #define CALC_LOAD(load,exp,n) \
86 load *= exp; \
87 load += n*(FIXED_1-exp); \
88 load >>= FSHIFT;
89
90 extern unsigned long total_forks;
91 extern int nr_threads;
92 extern int last_pid;
93 DECLARE_PER_CPU(unsigned long, process_counts);
94 extern int nr_processes(void);
95 extern unsigned long nr_running(void);
96 extern unsigned long nr_uninterruptible(void);
97 extern unsigned long nr_iowait(void);
98
99 #include <linux/time.h>
100 #include <linux/param.h>
101 #include <linux/resource.h>
102 #include <linux/timer.h>
103
104 #include <asm/processor.h>
105
106 #define TASK_RUNNING 0
107 #define TASK_INTERRUPTIBLE 1
108 #define TASK_UNINTERRUPTIBLE 2
109 #define TASK_STOPPED 4
110 #define TASK_TRACED 8
111 #define EXIT_ZOMBIE 16
112 #define EXIT_DEAD 32
113
114 #define __set_task_state(tsk, state_value) \
115 do { (tsk)->state = (state_value); } while (0)
116 #define set_task_state(tsk, state_value) \
117 set_mb((tsk)->state, (state_value))
118
119 #define __set_current_state(state_value) \
120 do { current->state = (state_value); } while (0)
121 #define set_current_state(state_value) \
122 set_mb(current->state, (state_value))
123
124 /* Task command name length */
125 #define TASK_COMM_LEN 16
126
127 /*
128 * Scheduling policies
129 */
130 #define SCHED_NORMAL 0
131 #define SCHED_FIFO 1
132 #define SCHED_RR 2
133
134 struct sched_param {
135 int sched_priority;
136 };
137
138 #ifdef __KERNEL__
139
140 #include <linux/spinlock.h>
141
142 /*
143 * This serializes "schedule()" and also protects
144 * the run-queue from deletions/modifications (but
145 * _adding_ to the beginning of the run-queue has
146 * a separate lock).
147 */
148 extern rwlock_t tasklist_lock;
149 extern spinlock_t mmlist_lock;
150
151 typedef struct task_struct task_t;
152
153 extern void sched_init(void);
154 extern void sched_init_smp(void);
155 extern void init_idle(task_t *idle, int cpu);
156
157 extern cpumask_t nohz_cpu_mask;
158
159 extern void show_state(void);
160 extern void show_regs(struct pt_regs *);
161
162 /*
163 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
164 * task), SP is the stack pointer of the first frame that should be shown in the back
165 * trace (or NULL if the entire call-chain of the task should be shown).
166 */
167 extern void show_stack(struct task_struct *task, unsigned long *sp);
168
169 void io_schedule(void);
170 long io_schedule_timeout(long timeout);
171
172 extern void cpu_init (void);
173 extern void trap_init(void);
174 extern void update_process_times(int user);
175 extern void scheduler_tick(void);
176 extern unsigned long cache_decay_ticks;
177
178 /* Attach to any functions which should be ignored in wchan output. */
179 #define __sched __attribute__((__section__(".sched.text")))
180 /* Is this address in the __sched functions? */
181 extern int in_sched_functions(unsigned long addr);
182
183 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
184 extern signed long FASTCALL(schedule_timeout(signed long timeout));
185 asmlinkage void schedule(void);
186
187 struct namespace;
188
189 /* Maximum number of active map areas.. This is a random (large) number */
190 #define DEFAULT_MAX_MAP_COUNT 65536
191
192 extern int sysctl_max_map_count;
193
194 #include <linux/aio.h>
195
196 extern unsigned long
197 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
198 unsigned long, unsigned long);
199 extern unsigned long
200 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
201 unsigned long len, unsigned long pgoff,
202 unsigned long flags);
203 extern void arch_unmap_area(struct vm_area_struct *area);
204 extern void arch_unmap_area_topdown(struct vm_area_struct *area);
205
206
207 struct mm_struct {
208 struct vm_area_struct * mmap; /* list of VMAs */
209 struct rb_root mm_rb;
210 struct vm_area_struct * mmap_cache; /* last find_vma result */
211 unsigned long (*get_unmapped_area) (struct file *filp,
212 unsigned long addr, unsigned long len,
213 unsigned long pgoff, unsigned long flags);
214 void (*unmap_area) (struct vm_area_struct *area);
215 unsigned long mmap_base; /* base of mmap area */
216 unsigned long free_area_cache; /* first hole */
217 pgd_t * pgd;
218 atomic_t mm_users; /* How many users with user space? */
219 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
220 int map_count; /* number of VMAs */
221 struct rw_semaphore mmap_sem;
222 spinlock_t page_table_lock; /* Protects page tables, mm->rss, mm->anon_rss */
223
224 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
225 * together off init_mm.mmlist, and are protected
226 * by mmlist_lock
227 */
228
229 unsigned long start_code, end_code, start_data, end_data;
230 unsigned long start_brk, brk, start_stack;
231 unsigned long arg_start, arg_end, env_start, env_end;
232 unsigned long rss, anon_rss, total_vm, locked_vm, shared_vm;
233 unsigned long exec_vm, stack_vm, reserved_vm, def_flags, nr_ptes;
234
235 unsigned long saved_auxv[42]; /* for /proc/PID/auxv */
236
237 unsigned dumpable:1;
238 cpumask_t cpu_vm_mask;
239
240 /* Architecture-specific MM context */
241 mm_context_t context;
242
243 /* Token based thrashing protection. */
244 unsigned long swap_token_time;
245 char recent_pagein;
246
247 /* coredumping support */
248 int core_waiters;
249 struct completion *core_startup_done, core_done;
250
251 /* aio bits */
252 rwlock_t ioctx_list_lock;
253 struct kioctx *ioctx_list;
254
255 struct kioctx default_kioctx;
256
257 unsigned long hiwater_rss; /* High-water RSS usage */
258 unsigned long hiwater_vm; /* High-water virtual memory usage */
259 };
260
261 struct sighand_struct {
262 atomic_t count;
263 struct k_sigaction action[_NSIG];
264 spinlock_t siglock;
265 };
266
267 /*
268 * NOTE! "signal_struct" does not have it's own
269 * locking, because a shared signal_struct always
270 * implies a shared sighand_struct, so locking
271 * sighand_struct is always a proper superset of
272 * the locking of signal_struct.
273 */
274 struct signal_struct {
275 atomic_t count;
276 atomic_t live;
277
278 wait_queue_head_t wait_chldexit; /* for wait4() */
279
280 /* current thread group signal load-balancing target: */
281 task_t *curr_target;
282
283 /* shared signal handling: */
284 struct sigpending shared_pending;
285
286 /* thread group exit support */
287 int group_exit_code;
288 /* overloaded:
289 * - notify group_exit_task when ->count is equal to notify_count
290 * - everyone except group_exit_task is stopped during signal delivery
291 * of fatal signals, group_exit_task processes the signal.
292 */
293 struct task_struct *group_exit_task;
294 int notify_count;
295
296 /* thread group stop support, overloads group_exit_code too */
297 int group_stop_count;
298 unsigned int flags; /* see SIGNAL_* flags below */
299
300 /* POSIX.1b Interval Timers */
301 struct list_head posix_timers;
302
303 /* job control IDs */
304 pid_t pgrp;
305 pid_t tty_old_pgrp;
306 pid_t session;
307 /* boolean value for session group leader */
308 int leader;
309
310 struct tty_struct *tty; /* NULL if no tty */
311
312 /*
313 * Cumulative resource counters for dead threads in the group,
314 * and for reaped dead child processes forked by this group.
315 * Live threads maintain their own counters and add to these
316 * in __exit_signal, except for the group leader.
317 */
318 cputime_t utime, stime, cutime, cstime;
319 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
320 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
321
322 /*
323 * We don't bother to synchronize most readers of this at all,
324 * because there is no reader checking a limit that actually needs
325 * to get both rlim_cur and rlim_max atomically, and either one
326 * alone is a single word that can safely be read normally.
327 * getrlimit/setrlimit use task_lock(current->group_leader) to
328 * protect this instead of the siglock, because they really
329 * have no need to disable irqs.
330 */
331 struct rlimit rlim[RLIM_NLIMITS];
332 };
333
334 /*
335 * Bits in flags field of signal_struct.
336 */
337 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
338 #define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
339 #define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
340 #define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
341
342
343 /*
344 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
345 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL tasks are
346 * in the range MAX_RT_PRIO..MAX_PRIO-1. Priority values
347 * are inverted: lower p->prio value means higher priority.
348 *
349 * The MAX_USER_RT_PRIO value allows the actual maximum
350 * RT priority to be separate from the value exported to
351 * user-space. This allows kernel threads to set their
352 * priority to a value higher than any user task. Note:
353 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
354 */
355
356 #define MAX_USER_RT_PRIO 100
357 #define MAX_RT_PRIO MAX_USER_RT_PRIO
358
359 #define MAX_PRIO (MAX_RT_PRIO + 40)
360
361 #define rt_task(p) (unlikely((p)->prio < MAX_RT_PRIO))
362
363 /*
364 * Some day this will be a full-fledged user tracking system..
365 */
366 struct user_struct {
367 atomic_t __count; /* reference count */
368 atomic_t processes; /* How many processes does this user have? */
369 atomic_t files; /* How many open files does this user have? */
370 atomic_t sigpending; /* How many pending signals does this user have? */
371 /* protected by mq_lock */
372 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
373 unsigned long locked_shm; /* How many pages of mlocked shm ? */
374
375 #ifdef CONFIG_KEYS
376 struct key *uid_keyring; /* UID specific keyring */
377 struct key *session_keyring; /* UID's default session keyring */
378 #endif
379
380 /* Hash table maintenance information */
381 struct list_head uidhash_list;
382 uid_t uid;
383 };
384
385 extern struct user_struct *find_user(uid_t);
386
387 extern struct user_struct root_user;
388 #define INIT_USER (&root_user)
389
390 typedef struct prio_array prio_array_t;
391 struct backing_dev_info;
392 struct reclaim_state;
393
394 #ifdef CONFIG_SCHEDSTATS
395 struct sched_info {
396 /* cumulative counters */
397 unsigned long cpu_time, /* time spent on the cpu */
398 run_delay, /* time spent waiting on a runqueue */
399 pcnt; /* # of timeslices run on this cpu */
400
401 /* timestamps */
402 unsigned long last_arrival, /* when we last ran on a cpu */
403 last_queued; /* when we were last queued to run */
404 };
405
406 extern struct file_operations proc_schedstat_operations;
407 #endif
408
409 enum idle_type
410 {
411 SCHED_IDLE,
412 NOT_IDLE,
413 NEWLY_IDLE,
414 MAX_IDLE_TYPES
415 };
416
417 /*
418 * sched-domains (multiprocessor balancing) declarations:
419 */
420 #ifdef CONFIG_SMP
421 #define SCHED_LOAD_SCALE 128UL /* increase resolution of load */
422
423 #define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
424 #define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
425 #define SD_BALANCE_EXEC 4 /* Balance on exec */
426 #define SD_WAKE_IDLE 8 /* Wake to idle CPU on task wakeup */
427 #define SD_WAKE_AFFINE 16 /* Wake task to waking CPU */
428 #define SD_WAKE_BALANCE 32 /* Perform balancing at task wakeup */
429 #define SD_SHARE_CPUPOWER 64 /* Domain members share cpu power */
430
431 struct sched_group {
432 struct sched_group *next; /* Must be a circular list */
433 cpumask_t cpumask;
434
435 /*
436 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
437 * single CPU. This is read only (except for setup, hotplug CPU).
438 */
439 unsigned long cpu_power;
440 };
441
442 struct sched_domain {
443 /* These fields must be setup */
444 struct sched_domain *parent; /* top domain must be null terminated */
445 struct sched_group *groups; /* the balancing groups of the domain */
446 cpumask_t span; /* span of all CPUs in this domain */
447 unsigned long min_interval; /* Minimum balance interval ms */
448 unsigned long max_interval; /* Maximum balance interval ms */
449 unsigned int busy_factor; /* less balancing by factor if busy */
450 unsigned int imbalance_pct; /* No balance until over watermark */
451 unsigned long long cache_hot_time; /* Task considered cache hot (ns) */
452 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
453 unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
454 int flags; /* See SD_* */
455
456 /* Runtime fields. */
457 unsigned long last_balance; /* init to jiffies. units in jiffies */
458 unsigned int balance_interval; /* initialise to 1. units in ms. */
459 unsigned int nr_balance_failed; /* initialise to 0 */
460
461 #ifdef CONFIG_SCHEDSTATS
462 /* load_balance() stats */
463 unsigned long lb_cnt[MAX_IDLE_TYPES];
464 unsigned long lb_failed[MAX_IDLE_TYPES];
465 unsigned long lb_imbalance[MAX_IDLE_TYPES];
466 unsigned long lb_nobusyg[MAX_IDLE_TYPES];
467 unsigned long lb_nobusyq[MAX_IDLE_TYPES];
468
469 /* sched_balance_exec() stats */
470 unsigned long sbe_attempts;
471 unsigned long sbe_pushed;
472
473 /* try_to_wake_up() stats */
474 unsigned long ttwu_wake_affine;
475 unsigned long ttwu_wake_balance;
476 #endif
477 };
478
479 #ifdef ARCH_HAS_SCHED_DOMAIN
480 /* Useful helpers that arch setup code may use. Defined in kernel/sched.c */
481 extern cpumask_t cpu_isolated_map;
482 extern void init_sched_build_groups(struct sched_group groups[],
483 cpumask_t span, int (*group_fn)(int cpu));
484 extern void cpu_attach_domain(struct sched_domain *sd, int cpu);
485 #endif /* ARCH_HAS_SCHED_DOMAIN */
486 #endif /* CONFIG_SMP */
487
488
489 struct io_context; /* See blkdev.h */
490 void exit_io_context(void);
491
492 #define NGROUPS_SMALL 32
493 #define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
494 struct group_info {
495 int ngroups;
496 atomic_t usage;
497 gid_t small_block[NGROUPS_SMALL];
498 int nblocks;
499 gid_t *blocks[0];
500 };
501
502 /*
503 * get_group_info() must be called with the owning task locked (via task_lock())
504 * when task != current. The reason being that the vast majority of callers are
505 * looking at current->group_info, which can not be changed except by the
506 * current task. Changing current->group_info requires the task lock, too.
507 */
508 #define get_group_info(group_info) do { \
509 atomic_inc(&(group_info)->usage); \
510 } while (0)
511
512 #define put_group_info(group_info) do { \
513 if (atomic_dec_and_test(&(group_info)->usage)) \
514 groups_free(group_info); \
515 } while (0)
516
517 struct group_info *groups_alloc(int gidsetsize);
518 void groups_free(struct group_info *group_info);
519 int set_current_groups(struct group_info *group_info);
520 /* access the groups "array" with this macro */
521 #define GROUP_AT(gi, i) \
522 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
523
524
525 struct audit_context; /* See audit.c */
526 struct mempolicy;
527
528 struct task_struct {
529 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
530 struct thread_info *thread_info;
531 atomic_t usage;
532 unsigned long flags; /* per process flags, defined below */
533 unsigned long ptrace;
534
535 int lock_depth; /* Lock depth */
536
537 int prio, static_prio;
538 struct list_head run_list;
539 prio_array_t *array;
540
541 unsigned long sleep_avg;
542 unsigned long long timestamp, last_ran;
543 int activated;
544
545 unsigned long policy;
546 cpumask_t cpus_allowed;
547 unsigned int time_slice, first_time_slice;
548
549 #ifdef CONFIG_SCHEDSTATS
550 struct sched_info sched_info;
551 #endif
552
553 struct list_head tasks;
554 /*
555 * ptrace_list/ptrace_children forms the list of my children
556 * that were stolen by a ptracer.
557 */
558 struct list_head ptrace_children;
559 struct list_head ptrace_list;
560
561 struct mm_struct *mm, *active_mm;
562
563 /* task state */
564 struct linux_binfmt *binfmt;
565 long exit_state;
566 int exit_code, exit_signal;
567 int pdeath_signal; /* The signal sent when the parent dies */
568 /* ??? */
569 unsigned long personality;
570 unsigned did_exec:1;
571 pid_t pid;
572 pid_t tgid;
573 /*
574 * pointers to (original) parent process, youngest child, younger sibling,
575 * older sibling, respectively. (p->father can be replaced with
576 * p->parent->pid)
577 */
578 struct task_struct *real_parent; /* real parent process (when being debugged) */
579 struct task_struct *parent; /* parent process */
580 /*
581 * children/sibling forms the list of my children plus the
582 * tasks I'm ptracing.
583 */
584 struct list_head children; /* list of my children */
585 struct list_head sibling; /* linkage in my parent's children list */
586 struct task_struct *group_leader; /* threadgroup leader */
587
588 /* PID/PID hash table linkage. */
589 struct pid pids[PIDTYPE_MAX];
590
591 struct completion *vfork_done; /* for vfork() */
592 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
593 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
594
595 unsigned long rt_priority;
596 unsigned long it_real_value, it_real_incr;
597 cputime_t it_virt_value, it_virt_incr;
598 cputime_t it_prof_value, it_prof_incr;
599 struct timer_list real_timer;
600 cputime_t utime, stime;
601 unsigned long nvcsw, nivcsw; /* context switch counts */
602 struct timespec start_time;
603 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
604 unsigned long min_flt, maj_flt;
605 /* process credentials */
606 uid_t uid,euid,suid,fsuid;
607 gid_t gid,egid,sgid,fsgid;
608 struct group_info *group_info;
609 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
610 unsigned keep_capabilities:1;
611 struct user_struct *user;
612 #ifdef CONFIG_KEYS
613 struct key *session_keyring; /* keyring inherited over fork */
614 struct key *process_keyring; /* keyring private to this process (CLONE_THREAD) */
615 struct key *thread_keyring; /* keyring private to this thread */
616 #endif
617 int oomkilladj; /* OOM kill score adjustment (bit shift). */
618 char comm[TASK_COMM_LEN];
619 /* file system info */
620 int link_count, total_link_count;
621 /* ipc stuff */
622 struct sysv_sem sysvsem;
623 /* CPU-specific state of this task */
624 struct thread_struct thread;
625 /* filesystem information */
626 struct fs_struct *fs;
627 /* open file information */
628 struct files_struct *files;
629 /* namespace */
630 struct namespace *namespace;
631 /* signal handlers */
632 struct signal_struct *signal;
633 struct sighand_struct *sighand;
634
635 sigset_t blocked, real_blocked;
636 struct sigpending pending;
637
638 unsigned long sas_ss_sp;
639 size_t sas_ss_size;
640 int (*notifier)(void *priv);
641 void *notifier_data;
642 sigset_t *notifier_mask;
643
644 void *security;
645 struct audit_context *audit_context;
646
647 /* Thread group tracking */
648 u32 parent_exec_id;
649 u32 self_exec_id;
650 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
651 spinlock_t alloc_lock;
652 /* Protection of proc_dentry: nesting proc_lock, dcache_lock, write_lock_irq(&tasklist_lock); */
653 spinlock_t proc_lock;
654 /* context-switch lock */
655 spinlock_t switch_lock;
656
657 /* journalling filesystem info */
658 void *journal_info;
659
660 /* VM state */
661 struct reclaim_state *reclaim_state;
662
663 struct dentry *proc_dentry;
664 struct backing_dev_info *backing_dev_info;
665
666 struct io_context *io_context;
667
668 unsigned long ptrace_message;
669 siginfo_t *last_siginfo; /* For ptrace use. */
670 /*
671 * current io wait handle: wait queue entry to use for io waits
672 * If this thread is processing aio, this points at the waitqueue
673 * inside the currently handled kiocb. It may be NULL (i.e. default
674 * to a stack based synchronous wait) if its doing sync IO.
675 */
676 wait_queue_t *io_wait;
677 /* i/o counters(bytes read/written, #syscalls */
678 u64 rchar, wchar, syscr, syscw;
679 #if defined(CONFIG_BSD_PROCESS_ACCT)
680 u64 acct_rss_mem1; /* accumulated rss usage */
681 u64 acct_vm_mem1; /* accumulated virtual memory usage */
682 clock_t acct_stimexpd; /* clock_t-converted stime since last update */
683 #endif
684 #ifdef CONFIG_NUMA
685 struct mempolicy *mempolicy;
686 short il_next;
687 #endif
688 };
689
690 static inline pid_t process_group(struct task_struct *tsk)
691 {
692 return tsk->signal->pgrp;
693 }
694
695 /**
696 * pid_alive - check that a task structure is not stale
697 * @p: Task structure to be checked.
698 *
699 * Test if a process is not yet dead (at most zombie state)
700 * If pid_alive fails, then pointers within the task structure
701 * can be stale and must not be dereferenced.
702 */
703 static inline int pid_alive(struct task_struct *p)
704 {
705 return p->pids[PIDTYPE_PID].nr != 0;
706 }
707
708 extern void free_task(struct task_struct *tsk);
709 extern void __put_task_struct(struct task_struct *tsk);
710 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
711 #define put_task_struct(tsk) \
712 do { if (atomic_dec_and_test(&(tsk)->usage)) __put_task_struct(tsk); } while(0)
713
714 /*
715 * Per process flags
716 */
717 #define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
718 /* Not implemented yet, only for 486*/
719 #define PF_STARTING 0x00000002 /* being created */
720 #define PF_EXITING 0x00000004 /* getting shut down */
721 #define PF_DEAD 0x00000008 /* Dead */
722 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
723 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
724 #define PF_DUMPCORE 0x00000200 /* dumped core */
725 #define PF_SIGNALED 0x00000400 /* killed by a signal */
726 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
727 #define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
728 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
729 #define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */
730 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
731 #define PF_FROZEN 0x00010000 /* frozen for system suspend */
732 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
733 #define PF_KSWAPD 0x00040000 /* I am kswapd */
734 #define PF_SWAPOFF 0x00080000 /* I am in swapoff */
735 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
736 #define PF_SYNCWRITE 0x00200000 /* I am doing a sync write */
737 #define PF_BORROWED_MM 0x00400000 /* I am a kthread doing use_mm */
738
739 /*
740 * Only the _current_ task can read/write to tsk->flags, but other
741 * tasks can access tsk->flags in readonly mode for example
742 * with tsk_used_math (like during threaded core dumping).
743 * There is however an exception to this rule during ptrace
744 * or during fork: the ptracer task is allowed to write to the
745 * child->flags of its traced child (same goes for fork, the parent
746 * can write to the child->flags), because we're guaranteed the
747 * child is not running and in turn not changing child->flags
748 * at the same time the parent does it.
749 */
750 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
751 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
752 #define clear_used_math() clear_stopped_child_used_math(current)
753 #define set_used_math() set_stopped_child_used_math(current)
754 #define conditional_stopped_child_used_math(condition, child) \
755 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
756 #define conditional_used_math(condition) \
757 conditional_stopped_child_used_math(condition, current)
758 #define copy_to_stopped_child_used_math(child) \
759 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
760 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
761 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
762 #define used_math() tsk_used_math(current)
763
764 #ifdef CONFIG_SMP
765 extern int set_cpus_allowed(task_t *p, cpumask_t new_mask);
766 #else
767 static inline int set_cpus_allowed(task_t *p, cpumask_t new_mask)
768 {
769 if (!cpus_intersects(new_mask, cpu_online_map))
770 return -EINVAL;
771 return 0;
772 }
773 #endif
774
775 extern unsigned long long sched_clock(void);
776
777 /* sched_exec is called by processes performing an exec */
778 #ifdef CONFIG_SMP
779 extern void sched_exec(void);
780 #else
781 #define sched_exec() {}
782 #endif
783
784 #ifdef CONFIG_HOTPLUG_CPU
785 extern void idle_task_exit(void);
786 #else
787 static inline void idle_task_exit(void) {}
788 #endif
789
790 extern void sched_idle_next(void);
791 extern void set_user_nice(task_t *p, long nice);
792 extern int task_prio(const task_t *p);
793 extern int task_nice(const task_t *p);
794 extern int task_curr(const task_t *p);
795 extern int idle_cpu(int cpu);
796 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
797 extern task_t *idle_task(int cpu);
798
799 void yield(void);
800
801 /*
802 * The default (Linux) execution domain.
803 */
804 extern struct exec_domain default_exec_domain;
805
806 union thread_union {
807 struct thread_info thread_info;
808 unsigned long stack[THREAD_SIZE/sizeof(long)];
809 };
810
811 #ifndef __HAVE_ARCH_KSTACK_END
812 static inline int kstack_end(void *addr)
813 {
814 /* Reliable end of stack detection:
815 * Some APM bios versions misalign the stack
816 */
817 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
818 }
819 #endif
820
821 extern union thread_union init_thread_union;
822 extern struct task_struct init_task;
823
824 extern struct mm_struct init_mm;
825
826 #define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
827 extern struct task_struct *find_task_by_pid_type(int type, int pid);
828 extern void set_special_pids(pid_t session, pid_t pgrp);
829 extern void __set_special_pids(pid_t session, pid_t pgrp);
830
831 /* per-UID process charging. */
832 extern struct user_struct * alloc_uid(uid_t);
833 static inline struct user_struct *get_uid(struct user_struct *u)
834 {
835 atomic_inc(&u->__count);
836 return u;
837 }
838 extern void free_uid(struct user_struct *);
839 extern void switch_uid(struct user_struct *);
840
841 #include <asm/current.h>
842
843 extern void do_timer(struct pt_regs *);
844
845 extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
846 extern int FASTCALL(wake_up_process(struct task_struct * tsk));
847 extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
848 unsigned long clone_flags));
849 #ifdef CONFIG_SMP
850 extern void kick_process(struct task_struct *tsk);
851 #else
852 static inline void kick_process(struct task_struct *tsk) { }
853 #endif
854 extern void FASTCALL(sched_fork(task_t * p));
855 extern void FASTCALL(sched_exit(task_t * p));
856
857 extern int in_group_p(gid_t);
858 extern int in_egroup_p(gid_t);
859
860 extern void proc_caches_init(void);
861 extern void flush_signals(struct task_struct *);
862 extern void flush_signal_handlers(struct task_struct *, int force_default);
863 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
864
865 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
866 {
867 unsigned long flags;
868 int ret;
869
870 spin_lock_irqsave(&tsk->sighand->siglock, flags);
871 ret = dequeue_signal(tsk, mask, info);
872 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
873
874 return ret;
875 }
876
877 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
878 sigset_t *mask);
879 extern void unblock_all_signals(void);
880 extern void release_task(struct task_struct * p);
881 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
882 extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
883 extern int force_sigsegv(int, struct task_struct *);
884 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
885 extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp);
886 extern int kill_pg_info(int, struct siginfo *, pid_t);
887 extern int kill_proc_info(int, struct siginfo *, pid_t);
888 extern void do_notify_parent(struct task_struct *, int);
889 extern void force_sig(int, struct task_struct *);
890 extern void force_sig_specific(int, struct task_struct *);
891 extern int send_sig(int, struct task_struct *, int);
892 extern void zap_other_threads(struct task_struct *p);
893 extern int kill_pg(pid_t, int, int);
894 extern int kill_sl(pid_t, int, int);
895 extern int kill_proc(pid_t, int, int);
896 extern struct sigqueue *sigqueue_alloc(void);
897 extern void sigqueue_free(struct sigqueue *);
898 extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
899 extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
900 extern int do_sigaction(int, const struct k_sigaction *, struct k_sigaction *);
901 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
902
903 /* These can be the second arg to send_sig_info/send_group_sig_info. */
904 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
905 #define SEND_SIG_PRIV ((struct siginfo *) 1)
906 #define SEND_SIG_FORCED ((struct siginfo *) 2)
907
908 /* True if we are on the alternate signal stack. */
909
910 static inline int on_sig_stack(unsigned long sp)
911 {
912 return (sp - current->sas_ss_sp < current->sas_ss_size);
913 }
914
915 static inline int sas_ss_flags(unsigned long sp)
916 {
917 return (current->sas_ss_size == 0 ? SS_DISABLE
918 : on_sig_stack(sp) ? SS_ONSTACK : 0);
919 }
920
921
922 #ifdef CONFIG_SECURITY
923 /* code is in security.c */
924 extern int capable(int cap);
925 #else
926 static inline int capable(int cap)
927 {
928 if (cap_raised(current->cap_effective, cap)) {
929 current->flags |= PF_SUPERPRIV;
930 return 1;
931 }
932 return 0;
933 }
934 #endif
935
936 /*
937 * Routines for handling mm_structs
938 */
939 extern struct mm_struct * mm_alloc(void);
940
941 /* mmdrop drops the mm and the page tables */
942 extern void FASTCALL(__mmdrop(struct mm_struct *));
943 static inline void mmdrop(struct mm_struct * mm)
944 {
945 if (atomic_dec_and_test(&mm->mm_count))
946 __mmdrop(mm);
947 }
948
949 /* mmput gets rid of the mappings and all user-space */
950 extern void mmput(struct mm_struct *);
951 /* Grab a reference to a task's mm, if it is not already going away */
952 extern struct mm_struct *get_task_mm(struct task_struct *task);
953 /* Remove the current tasks stale references to the old mm_struct */
954 extern void mm_release(struct task_struct *, struct mm_struct *);
955
956 extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
957 extern void flush_thread(void);
958 extern void exit_thread(void);
959
960 extern void exit_mm(struct task_struct *);
961 extern void exit_files(struct task_struct *);
962 extern void exit_signal(struct task_struct *);
963 extern void __exit_signal(struct task_struct *);
964 extern void exit_sighand(struct task_struct *);
965 extern void __exit_sighand(struct task_struct *);
966 extern void exit_itimers(struct signal_struct *);
967
968 extern NORET_TYPE void do_group_exit(int);
969
970 extern void reparent_to_init(void);
971 extern void daemonize(const char *, ...);
972 extern int allow_signal(int);
973 extern int disallow_signal(int);
974 extern task_t *child_reaper;
975
976 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
977 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
978 task_t *fork_idle(int);
979
980 extern void set_task_comm(struct task_struct *tsk, char *from);
981 extern void get_task_comm(char *to, struct task_struct *tsk);
982
983 #ifdef CONFIG_SMP
984 extern void wait_task_inactive(task_t * p);
985 #else
986 #define wait_task_inactive(p) do { } while (0)
987 #endif
988
989 #define remove_parent(p) list_del_init(&(p)->sibling)
990 #define add_parent(p, parent) list_add_tail(&(p)->sibling,&(parent)->children)
991
992 #define REMOVE_LINKS(p) do { \
993 if (thread_group_leader(p)) \
994 list_del_init(&(p)->tasks); \
995 remove_parent(p); \
996 } while (0)
997
998 #define SET_LINKS(p) do { \
999 if (thread_group_leader(p)) \
1000 list_add_tail(&(p)->tasks,&init_task.tasks); \
1001 add_parent(p, (p)->parent); \
1002 } while (0)
1003
1004 #define next_task(p) list_entry((p)->tasks.next, struct task_struct, tasks)
1005 #define prev_task(p) list_entry((p)->tasks.prev, struct task_struct, tasks)
1006
1007 #define for_each_process(p) \
1008 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1009
1010 /*
1011 * Careful: do_each_thread/while_each_thread is a double loop so
1012 * 'break' will not work as expected - use goto instead.
1013 */
1014 #define do_each_thread(g, t) \
1015 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1016
1017 #define while_each_thread(g, t) \
1018 while ((t = next_thread(t)) != g)
1019
1020 extern task_t * FASTCALL(next_thread(const task_t *p));
1021
1022 #define thread_group_leader(p) (p->pid == p->tgid)
1023
1024 static inline int thread_group_empty(task_t *p)
1025 {
1026 return list_empty(&p->pids[PIDTYPE_TGID].pid_list);
1027 }
1028
1029 #define delay_group_leader(p) \
1030 (thread_group_leader(p) && !thread_group_empty(p))
1031
1032 extern void unhash_process(struct task_struct *p);
1033
1034 /*
1035 * Protects ->fs, ->files, ->mm, ->ptrace, ->group_info, ->comm, keyring
1036 * subscriptions and synchronises with wait4(). Also used in procfs.
1037 *
1038 * Nests both inside and outside of read_lock(&tasklist_lock).
1039 * It must not be nested with write_lock_irq(&tasklist_lock),
1040 * neither inside nor outside.
1041 */
1042 static inline void task_lock(struct task_struct *p)
1043 {
1044 spin_lock(&p->alloc_lock);
1045 }
1046
1047 static inline void task_unlock(struct task_struct *p)
1048 {
1049 spin_unlock(&p->alloc_lock);
1050 }
1051
1052 /* set thread flags in other task's structures
1053 * - see asm/thread_info.h for TIF_xxxx flags available
1054 */
1055 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1056 {
1057 set_ti_thread_flag(tsk->thread_info,flag);
1058 }
1059
1060 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1061 {
1062 clear_ti_thread_flag(tsk->thread_info,flag);
1063 }
1064
1065 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1066 {
1067 return test_and_set_ti_thread_flag(tsk->thread_info,flag);
1068 }
1069
1070 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1071 {
1072 return test_and_clear_ti_thread_flag(tsk->thread_info,flag);
1073 }
1074
1075 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1076 {
1077 return test_ti_thread_flag(tsk->thread_info,flag);
1078 }
1079
1080 static inline void set_tsk_need_resched(struct task_struct *tsk)
1081 {
1082 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1083 }
1084
1085 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1086 {
1087 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1088 }
1089
1090 static inline int signal_pending(struct task_struct *p)
1091 {
1092 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1093 }
1094
1095 static inline int need_resched(void)
1096 {
1097 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1098 }
1099
1100 /*
1101 * cond_resched() and cond_resched_lock(): latency reduction via
1102 * explicit rescheduling in places that are safe. The return
1103 * value indicates whether a reschedule was done in fact.
1104 * cond_resched_lock() will drop the spinlock before scheduling,
1105 * cond_resched_softirq() will enable bhs before scheduling.
1106 */
1107 extern int cond_resched(void);
1108 extern int cond_resched_lock(spinlock_t * lock);
1109 extern int cond_resched_softirq(void);
1110
1111 /*
1112 * Does a critical section need to be broken due to another
1113 * task waiting?:
1114 */
1115 #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1116 # define need_lockbreak(lock) ((lock)->break_lock)
1117 #else
1118 # define need_lockbreak(lock) 0
1119 #endif
1120
1121 /*
1122 * Does a critical section need to be broken due to another
1123 * task waiting or preemption being signalled:
1124 */
1125 static inline int lock_need_resched(spinlock_t *lock)
1126 {
1127 if (need_lockbreak(lock) || need_resched())
1128 return 1;
1129 return 0;
1130 }
1131
1132 /* Reevaluate whether the task has signals pending delivery.
1133 This is required every time the blocked sigset_t changes.
1134 callers must hold sighand->siglock. */
1135
1136 extern FASTCALL(void recalc_sigpending_tsk(struct task_struct *t));
1137 extern void recalc_sigpending(void);
1138
1139 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1140
1141 /*
1142 * Wrappers for p->thread_info->cpu access. No-op on UP.
1143 */
1144 #ifdef CONFIG_SMP
1145
1146 static inline unsigned int task_cpu(const struct task_struct *p)
1147 {
1148 return p->thread_info->cpu;
1149 }
1150
1151 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1152 {
1153 p->thread_info->cpu = cpu;
1154 }
1155
1156 #else
1157
1158 static inline unsigned int task_cpu(const struct task_struct *p)
1159 {
1160 return 0;
1161 }
1162
1163 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1164 {
1165 }
1166
1167 #endif /* CONFIG_SMP */
1168
1169 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1170 extern void arch_pick_mmap_layout(struct mm_struct *mm);
1171 #else
1172 static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1173 {
1174 mm->mmap_base = TASK_UNMAPPED_BASE;
1175 mm->get_unmapped_area = arch_get_unmapped_area;
1176 mm->unmap_area = arch_unmap_area;
1177 }
1178 #endif
1179
1180 extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1181 extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1182
1183 #ifdef CONFIG_MAGIC_SYSRQ
1184
1185 extern void normalize_rt_tasks(void);
1186
1187 #endif
1188
1189 /* try_to_freeze
1190 *
1191 * Checks whether we need to enter the refrigerator
1192 * and returns 1 if we did so.
1193 */
1194 #ifdef CONFIG_PM
1195 extern void refrigerator(unsigned long);
1196 extern int freeze_processes(void);
1197 extern void thaw_processes(void);
1198
1199 static inline int try_to_freeze(unsigned long refrigerator_flags)
1200 {
1201 if (unlikely(current->flags & PF_FREEZE)) {
1202 refrigerator(refrigerator_flags);
1203 return 1;
1204 } else
1205 return 0;
1206 }
1207 #else
1208 static inline void refrigerator(unsigned long flag) {}
1209 static inline int freeze_processes(void) { BUG(); return 0; }
1210 static inline void thaw_processes(void) {}
1211
1212 static inline int try_to_freeze(unsigned long refrigerator_flags)
1213 {
1214 return 0;
1215 }
1216 #endif /* CONFIG_PM */
1217 #endif /* __KERNEL__ */
1218
1219 #endif
1220
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