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

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

Version: ~ [ linux-5.1-rc1 ] ~ [ linux-5.0.3 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.30 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.107 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.164 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.176 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.136 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.63 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 #ifndef _LINUX_SCHED_H
  2 #define _LINUX_SCHED_H
  3 
  4 /*
  5  * cloning flags:
  6  */
  7 #define CSIGNAL         0x000000ff      /* signal mask to be sent at exit */
  8 #define CLONE_VM        0x00000100      /* set if VM shared between processes */
  9 #define CLONE_FS        0x00000200      /* set if fs info shared between processes */
 10 #define CLONE_FILES     0x00000400      /* set if open files shared between processes */
 11 #define CLONE_SIGHAND   0x00000800      /* set if signal handlers and blocked signals shared */
 12 #define CLONE_PTRACE    0x00002000      /* set if we want to let tracing continue on the child too */
 13 #define CLONE_VFORK     0x00004000      /* set if the parent wants the child to wake it up on mm_release */
 14 #define CLONE_PARENT    0x00008000      /* set if we want to have the same parent as the cloner */
 15 #define CLONE_THREAD    0x00010000      /* Same thread group? */
 16 #define CLONE_NEWNS     0x00020000      /* New namespace group? */
 17 #define CLONE_SYSVSEM   0x00040000      /* share system V SEM_UNDO semantics */
 18 #define CLONE_SETTLS    0x00080000      /* create a new TLS for the child */
 19 #define CLONE_PARENT_SETTID     0x00100000      /* set the TID in the parent */
 20 #define CLONE_CHILD_CLEARTID    0x00200000      /* clear the TID in the child */
 21 #define CLONE_DETACHED          0x00400000      /* Unused, ignored */
 22 #define CLONE_UNTRACED          0x00800000      /* set if the tracing process can't force CLONE_PTRACE on this clone */
 23 #define CLONE_CHILD_SETTID      0x01000000      /* set the TID in the child */
 24 /* 0x02000000 was previously the unused CLONE_STOPPED (Start in stopped state)
 25    and is now available for re-use. */
 26 #define CLONE_NEWUTS            0x04000000      /* New utsname group? */
 27 #define CLONE_NEWIPC            0x08000000      /* New ipcs */
 28 #define CLONE_NEWUSER           0x10000000      /* New user namespace */
 29 #define CLONE_NEWPID            0x20000000      /* New pid namespace */
 30 #define CLONE_NEWNET            0x40000000      /* New network namespace */
 31 #define CLONE_IO                0x80000000      /* Clone io context */
 32 
 33 /*
 34  * Scheduling policies
 35  */
 36 #define SCHED_NORMAL            0
 37 #define SCHED_FIFO              1
 38 #define SCHED_RR                2
 39 #define SCHED_BATCH             3
 40 /* SCHED_ISO: reserved but not implemented yet */
 41 #define SCHED_IDLE              5
 42 /* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
 43 #define SCHED_RESET_ON_FORK     0x40000000
 44 
 45 #ifdef __KERNEL__
 46 
 47 struct ccs_domain_info;
 48 
 49 struct sched_param {
 50         int sched_priority;
 51 };
 52 
 53 #include <asm/param.h>  /* for HZ */
 54 
 55 #include <linux/capability.h>
 56 #include <linux/threads.h>
 57 #include <linux/kernel.h>
 58 #include <linux/types.h>
 59 #include <linux/timex.h>
 60 #include <linux/jiffies.h>
 61 #include <linux/rbtree.h>
 62 #include <linux/thread_info.h>
 63 #include <linux/cpumask.h>
 64 #include <linux/errno.h>
 65 #include <linux/nodemask.h>
 66 #include <linux/mm_types.h>
 67 
 68 #include <asm/system.h>
 69 #include <asm/page.h>
 70 #include <asm/ptrace.h>
 71 #include <asm/cputime.h>
 72 
 73 #include <linux/smp.h>
 74 #include <linux/sem.h>
 75 #include <linux/signal.h>
 76 #include <linux/compiler.h>
 77 #include <linux/completion.h>
 78 #include <linux/pid.h>
 79 #include <linux/percpu.h>
 80 #include <linux/topology.h>
 81 #include <linux/proportions.h>
 82 #include <linux/seccomp.h>
 83 #include <linux/rcupdate.h>
 84 #include <linux/rculist.h>
 85 #include <linux/rtmutex.h>
 86 
 87 #include <linux/time.h>
 88 #include <linux/param.h>
 89 #include <linux/resource.h>
 90 #include <linux/timer.h>
 91 #include <linux/hrtimer.h>
 92 #include <linux/task_io_accounting.h>
 93 #include <linux/latencytop.h>
 94 #include <linux/cred.h>
 95 
 96 #include <asm/processor.h>
 97 
 98 struct exec_domain;
 99 struct futex_pi_state;
100 struct robust_list_head;
101 struct bio_list;
102 struct fs_struct;
103 struct perf_event_context;
104 struct blk_plug;
105 
106 /*
107  * List of flags we want to share for kernel threads,
108  * if only because they are not used by them anyway.
109  */
110 #define CLONE_KERNEL    (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
111 
112 /*
113  * These are the constant used to fake the fixed-point load-average
114  * counting. Some notes:
115  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
116  *    a load-average precision of 10 bits integer + 11 bits fractional
117  *  - if you want to count load-averages more often, you need more
118  *    precision, or rounding will get you. With 2-second counting freq,
119  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
120  *    11 bit fractions.
121  */
122 extern unsigned long avenrun[];         /* Load averages */
123 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
124 
125 #define FSHIFT          11              /* nr of bits of precision */
126 #define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
127 #define LOAD_FREQ       (5*HZ+1)        /* 5 sec intervals */
128 #define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
129 #define EXP_5           2014            /* 1/exp(5sec/5min) */
130 #define EXP_15          2037            /* 1/exp(5sec/15min) */
131 
132 #define CALC_LOAD(load,exp,n) \
133         load *= exp; \
134         load += n*(FIXED_1-exp); \
135         load >>= FSHIFT;
136 
137 extern unsigned long total_forks;
138 extern int nr_threads;
139 DECLARE_PER_CPU(unsigned long, process_counts);
140 extern int nr_processes(void);
141 extern unsigned long nr_running(void);
142 extern unsigned long nr_uninterruptible(void);
143 extern unsigned long nr_iowait(void);
144 extern unsigned long nr_iowait_cpu(int cpu);
145 extern unsigned long this_cpu_load(void);
146 
147 
148 extern void calc_global_load(unsigned long ticks);
149 
150 extern unsigned long get_parent_ip(unsigned long addr);
151 
152 struct seq_file;
153 struct cfs_rq;
154 struct task_group;
155 #ifdef CONFIG_SCHED_DEBUG
156 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
157 extern void proc_sched_set_task(struct task_struct *p);
158 extern void
159 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
160 #else
161 static inline void
162 proc_sched_show_task(struct task_struct *p, struct seq_file *m)
163 {
164 }
165 static inline void proc_sched_set_task(struct task_struct *p)
166 {
167 }
168 static inline void
169 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
170 {
171 }
172 #endif
173 
174 /*
175  * Task state bitmask. NOTE! These bits are also
176  * encoded in fs/proc/array.c: get_task_state().
177  *
178  * We have two separate sets of flags: task->state
179  * is about runnability, while task->exit_state are
180  * about the task exiting. Confusing, but this way
181  * modifying one set can't modify the other one by
182  * mistake.
183  */
184 #define TASK_RUNNING            0
185 #define TASK_INTERRUPTIBLE      1
186 #define TASK_UNINTERRUPTIBLE    2
187 #define __TASK_STOPPED          4
188 #define __TASK_TRACED           8
189 /* in tsk->exit_state */
190 #define EXIT_ZOMBIE             16
191 #define EXIT_DEAD               32
192 /* in tsk->state again */
193 #define TASK_DEAD               64
194 #define TASK_WAKEKILL           128
195 #define TASK_WAKING             256
196 #define TASK_STATE_MAX          512
197 
198 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
199 
200 extern char ___assert_task_state[1 - 2*!!(
201                 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
202 
203 /* Convenience macros for the sake of set_task_state */
204 #define TASK_KILLABLE           (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
205 #define TASK_STOPPED            (TASK_WAKEKILL | __TASK_STOPPED)
206 #define TASK_TRACED             (TASK_WAKEKILL | __TASK_TRACED)
207 
208 /* Convenience macros for the sake of wake_up */
209 #define TASK_NORMAL             (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
210 #define TASK_ALL                (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
211 
212 /* get_task_state() */
213 #define TASK_REPORT             (TASK_RUNNING | TASK_INTERRUPTIBLE | \
214                                  TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
215                                  __TASK_TRACED)
216 
217 #define task_is_traced(task)    ((task->state & __TASK_TRACED) != 0)
218 #define task_is_stopped(task)   ((task->state & __TASK_STOPPED) != 0)
219 #define task_is_dead(task)      ((task)->exit_state != 0)
220 #define task_is_stopped_or_traced(task) \
221                         ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
222 #define task_contributes_to_load(task)  \
223                                 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
224                                  (task->flags & PF_FREEZING) == 0)
225 
226 #define __set_task_state(tsk, state_value)              \
227         do { (tsk)->state = (state_value); } while (0)
228 #define set_task_state(tsk, state_value)                \
229         set_mb((tsk)->state, (state_value))
230 
231 /*
232  * set_current_state() includes a barrier so that the write of current->state
233  * is correctly serialised wrt the caller's subsequent test of whether to
234  * actually sleep:
235  *
236  *      set_current_state(TASK_UNINTERRUPTIBLE);
237  *      if (do_i_need_to_sleep())
238  *              schedule();
239  *
240  * If the caller does not need such serialisation then use __set_current_state()
241  */
242 #define __set_current_state(state_value)                        \
243         do { current->state = (state_value); } while (0)
244 #define set_current_state(state_value)          \
245         set_mb(current->state, (state_value))
246 
247 /* Task command name length */
248 #define TASK_COMM_LEN 16
249 
250 #include <linux/spinlock.h>
251 
252 /*
253  * This serializes "schedule()" and also protects
254  * the run-queue from deletions/modifications (but
255  * _adding_ to the beginning of the run-queue has
256  * a separate lock).
257  */
258 extern rwlock_t tasklist_lock;
259 extern spinlock_t mmlist_lock;
260 
261 struct task_struct;
262 
263 #ifdef CONFIG_PROVE_RCU
264 extern int lockdep_tasklist_lock_is_held(void);
265 #endif /* #ifdef CONFIG_PROVE_RCU */
266 
267 extern void sched_init(void);
268 extern void sched_init_smp(void);
269 extern asmlinkage void schedule_tail(struct task_struct *prev);
270 extern void init_idle(struct task_struct *idle, int cpu);
271 extern void init_idle_bootup_task(struct task_struct *idle);
272 
273 extern int runqueue_is_locked(int cpu);
274 
275 extern cpumask_var_t nohz_cpu_mask;
276 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
277 extern void select_nohz_load_balancer(int stop_tick);
278 extern int get_nohz_timer_target(void);
279 #else
280 static inline void select_nohz_load_balancer(int stop_tick) { }
281 #endif
282 
283 /*
284  * Only dump TASK_* tasks. (0 for all tasks)
285  */
286 extern void show_state_filter(unsigned long state_filter);
287 
288 static inline void show_state(void)
289 {
290         show_state_filter(0);
291 }
292 
293 extern void show_regs(struct pt_regs *);
294 
295 /*
296  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
297  * task), SP is the stack pointer of the first frame that should be shown in the back
298  * trace (or NULL if the entire call-chain of the task should be shown).
299  */
300 extern void show_stack(struct task_struct *task, unsigned long *sp);
301 
302 void io_schedule(void);
303 long io_schedule_timeout(long timeout);
304 
305 extern void cpu_init (void);
306 extern void trap_init(void);
307 extern void update_process_times(int user);
308 extern void scheduler_tick(void);
309 
310 extern void sched_show_task(struct task_struct *p);
311 
312 #ifdef CONFIG_LOCKUP_DETECTOR
313 extern void touch_softlockup_watchdog(void);
314 extern void touch_softlockup_watchdog_sync(void);
315 extern void touch_all_softlockup_watchdogs(void);
316 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
317                                   void __user *buffer,
318                                   size_t *lenp, loff_t *ppos);
319 extern unsigned int  softlockup_panic;
320 void lockup_detector_init(void);
321 #else
322 static inline void touch_softlockup_watchdog(void)
323 {
324 }
325 static inline void touch_softlockup_watchdog_sync(void)
326 {
327 }
328 static inline void touch_all_softlockup_watchdogs(void)
329 {
330 }
331 static inline void lockup_detector_init(void)
332 {
333 }
334 #endif
335 
336 #ifdef CONFIG_DETECT_HUNG_TASK
337 extern unsigned int  sysctl_hung_task_panic;
338 extern unsigned long sysctl_hung_task_check_count;
339 extern unsigned long sysctl_hung_task_timeout_secs;
340 extern unsigned long sysctl_hung_task_warnings;
341 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
342                                          void __user *buffer,
343                                          size_t *lenp, loff_t *ppos);
344 #else
345 /* Avoid need for ifdefs elsewhere in the code */
346 enum { sysctl_hung_task_timeout_secs = 0 };
347 #endif
348 
349 /* Attach to any functions which should be ignored in wchan output. */
350 #define __sched         __attribute__((__section__(".sched.text")))
351 
352 /* Linker adds these: start and end of __sched functions */
353 extern char __sched_text_start[], __sched_text_end[];
354 
355 /* Is this address in the __sched functions? */
356 extern int in_sched_functions(unsigned long addr);
357 
358 #define MAX_SCHEDULE_TIMEOUT    LONG_MAX
359 extern signed long schedule_timeout(signed long timeout);
360 extern signed long schedule_timeout_interruptible(signed long timeout);
361 extern signed long schedule_timeout_killable(signed long timeout);
362 extern signed long schedule_timeout_uninterruptible(signed long timeout);
363 asmlinkage void schedule(void);
364 extern int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner);
365 
366 struct nsproxy;
367 struct user_namespace;
368 
369 /*
370  * Default maximum number of active map areas, this limits the number of vmas
371  * per mm struct. Users can overwrite this number by sysctl but there is a
372  * problem.
373  *
374  * When a program's coredump is generated as ELF format, a section is created
375  * per a vma. In ELF, the number of sections is represented in unsigned short.
376  * This means the number of sections should be smaller than 65535 at coredump.
377  * Because the kernel adds some informative sections to a image of program at
378  * generating coredump, we need some margin. The number of extra sections is
379  * 1-3 now and depends on arch. We use "5" as safe margin, here.
380  */
381 #define MAPCOUNT_ELF_CORE_MARGIN        (5)
382 #define DEFAULT_MAX_MAP_COUNT   (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
383 
384 extern int sysctl_max_map_count;
385 
386 #include <linux/aio.h>
387 
388 #ifdef CONFIG_MMU
389 extern void arch_pick_mmap_layout(struct mm_struct *mm);
390 extern unsigned long
391 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
392                        unsigned long, unsigned long);
393 extern unsigned long
394 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
395                           unsigned long len, unsigned long pgoff,
396                           unsigned long flags);
397 extern void arch_unmap_area(struct mm_struct *, unsigned long);
398 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
399 #else
400 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
401 #endif
402 
403 
404 extern void set_dumpable(struct mm_struct *mm, int value);
405 extern int get_dumpable(struct mm_struct *mm);
406 
407 /* mm flags */
408 /* dumpable bits */
409 #define MMF_DUMPABLE      0  /* core dump is permitted */
410 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
411 
412 #define MMF_DUMPABLE_BITS 2
413 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
414 
415 /* coredump filter bits */
416 #define MMF_DUMP_ANON_PRIVATE   2
417 #define MMF_DUMP_ANON_SHARED    3
418 #define MMF_DUMP_MAPPED_PRIVATE 4
419 #define MMF_DUMP_MAPPED_SHARED  5
420 #define MMF_DUMP_ELF_HEADERS    6
421 #define MMF_DUMP_HUGETLB_PRIVATE 7
422 #define MMF_DUMP_HUGETLB_SHARED  8
423 
424 #define MMF_DUMP_FILTER_SHIFT   MMF_DUMPABLE_BITS
425 #define MMF_DUMP_FILTER_BITS    7
426 #define MMF_DUMP_FILTER_MASK \
427         (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
428 #define MMF_DUMP_FILTER_DEFAULT \
429         ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
430          (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
431 
432 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
433 # define MMF_DUMP_MASK_DEFAULT_ELF      (1 << MMF_DUMP_ELF_HEADERS)
434 #else
435 # define MMF_DUMP_MASK_DEFAULT_ELF      0
436 #endif
437                                         /* leave room for more dump flags */
438 #define MMF_VM_MERGEABLE        16      /* KSM may merge identical pages */
439 #define MMF_VM_HUGEPAGE         17      /* set when VM_HUGEPAGE is set on vma */
440 
441 #define MMF_INIT_MASK           (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
442 
443 struct sighand_struct {
444         atomic_t                count;
445         struct k_sigaction      action[_NSIG];
446         spinlock_t              siglock;
447         wait_queue_head_t       signalfd_wqh;
448 };
449 
450 struct pacct_struct {
451         int                     ac_flag;
452         long                    ac_exitcode;
453         unsigned long           ac_mem;
454         cputime_t               ac_utime, ac_stime;
455         unsigned long           ac_minflt, ac_majflt;
456 };
457 
458 struct cpu_itimer {
459         cputime_t expires;
460         cputime_t incr;
461         u32 error;
462         u32 incr_error;
463 };
464 
465 /**
466  * struct task_cputime - collected CPU time counts
467  * @utime:              time spent in user mode, in &cputime_t units
468  * @stime:              time spent in kernel mode, in &cputime_t units
469  * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
470  *
471  * This structure groups together three kinds of CPU time that are
472  * tracked for threads and thread groups.  Most things considering
473  * CPU time want to group these counts together and treat all three
474  * of them in parallel.
475  */
476 struct task_cputime {
477         cputime_t utime;
478         cputime_t stime;
479         unsigned long long sum_exec_runtime;
480 };
481 /* Alternate field names when used to cache expirations. */
482 #define prof_exp        stime
483 #define virt_exp        utime
484 #define sched_exp       sum_exec_runtime
485 
486 #define INIT_CPUTIME    \
487         (struct task_cputime) {                                 \
488                 .utime = cputime_zero,                          \
489                 .stime = cputime_zero,                          \
490                 .sum_exec_runtime = 0,                          \
491         }
492 
493 /*
494  * Disable preemption until the scheduler is running.
495  * Reset by start_kernel()->sched_init()->init_idle().
496  *
497  * We include PREEMPT_ACTIVE to avoid cond_resched() from working
498  * before the scheduler is active -- see should_resched().
499  */
500 #define INIT_PREEMPT_COUNT      (1 + PREEMPT_ACTIVE)
501 
502 /**
503  * struct thread_group_cputimer - thread group interval timer counts
504  * @cputime:            thread group interval timers.
505  * @running:            non-zero when there are timers running and
506  *                      @cputime receives updates.
507  * @lock:               lock for fields in this struct.
508  *
509  * This structure contains the version of task_cputime, above, that is
510  * used for thread group CPU timer calculations.
511  */
512 struct thread_group_cputimer {
513         struct task_cputime cputime;
514         int running;
515         spinlock_t lock;
516 };
517 
518 #include <linux/rwsem.h>
519 struct autogroup;
520 
521 /*
522  * NOTE! "signal_struct" does not have its own
523  * locking, because a shared signal_struct always
524  * implies a shared sighand_struct, so locking
525  * sighand_struct is always a proper superset of
526  * the locking of signal_struct.
527  */
528 struct signal_struct {
529         atomic_t                sigcnt;
530         atomic_t                live;
531         int                     nr_threads;
532 
533         wait_queue_head_t       wait_chldexit;  /* for wait4() */
534 
535         /* current thread group signal load-balancing target: */
536         struct task_struct      *curr_target;
537 
538         /* shared signal handling: */
539         struct sigpending       shared_pending;
540 
541         /* thread group exit support */
542         int                     group_exit_code;
543         /* overloaded:
544          * - notify group_exit_task when ->count is equal to notify_count
545          * - everyone except group_exit_task is stopped during signal delivery
546          *   of fatal signals, group_exit_task processes the signal.
547          */
548         int                     notify_count;
549         struct task_struct      *group_exit_task;
550 
551         /* thread group stop support, overloads group_exit_code too */
552         int                     group_stop_count;
553         unsigned int            flags; /* see SIGNAL_* flags below */
554 
555         /* POSIX.1b Interval Timers */
556         struct list_head posix_timers;
557 
558         /* ITIMER_REAL timer for the process */
559         struct hrtimer real_timer;
560         struct pid *leader_pid;
561         ktime_t it_real_incr;
562 
563         /*
564          * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
565          * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
566          * values are defined to 0 and 1 respectively
567          */
568         struct cpu_itimer it[2];
569 
570         /*
571          * Thread group totals for process CPU timers.
572          * See thread_group_cputimer(), et al, for details.
573          */
574         struct thread_group_cputimer cputimer;
575 
576         /* Earliest-expiration cache. */
577         struct task_cputime cputime_expires;
578 
579         struct list_head cpu_timers[3];
580 
581         struct pid *tty_old_pgrp;
582 
583         /* boolean value for session group leader */
584         int leader;
585 
586         struct tty_struct *tty; /* NULL if no tty */
587 
588 #ifdef CONFIG_SCHED_AUTOGROUP
589         struct autogroup *autogroup;
590 #endif
591         /*
592          * Cumulative resource counters for dead threads in the group,
593          * and for reaped dead child processes forked by this group.
594          * Live threads maintain their own counters and add to these
595          * in __exit_signal, except for the group leader.
596          */
597         cputime_t utime, stime, cutime, cstime;
598         cputime_t gtime;
599         cputime_t cgtime;
600 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
601         cputime_t prev_utime, prev_stime;
602 #endif
603         unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
604         unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
605         unsigned long inblock, oublock, cinblock, coublock;
606         unsigned long maxrss, cmaxrss;
607         struct task_io_accounting ioac;
608 
609         /*
610          * Cumulative ns of schedule CPU time fo dead threads in the
611          * group, not including a zombie group leader, (This only differs
612          * from jiffies_to_ns(utime + stime) if sched_clock uses something
613          * other than jiffies.)
614          */
615         unsigned long long sum_sched_runtime;
616 
617         /*
618          * We don't bother to synchronize most readers of this at all,
619          * because there is no reader checking a limit that actually needs
620          * to get both rlim_cur and rlim_max atomically, and either one
621          * alone is a single word that can safely be read normally.
622          * getrlimit/setrlimit use task_lock(current->group_leader) to
623          * protect this instead of the siglock, because they really
624          * have no need to disable irqs.
625          */
626         struct rlimit rlim[RLIM_NLIMITS];
627 
628 #ifdef CONFIG_BSD_PROCESS_ACCT
629         struct pacct_struct pacct;      /* per-process accounting information */
630 #endif
631 #ifdef CONFIG_TASKSTATS
632         struct taskstats *stats;
633 #endif
634 #ifdef CONFIG_AUDIT
635         unsigned audit_tty;
636         struct tty_audit_buf *tty_audit_buf;
637 #endif
638 #ifdef CONFIG_CGROUPS
639         /*
640          * The threadgroup_fork_lock prevents threads from forking with
641          * CLONE_THREAD while held for writing. Use this for fork-sensitive
642          * threadgroup-wide operations. It's taken for reading in fork.c in
643          * copy_process().
644          * Currently only needed write-side by cgroups.
645          */
646         struct rw_semaphore threadgroup_fork_lock;
647 #endif
648 
649         int oom_adj;            /* OOM kill score adjustment (bit shift) */
650         int oom_score_adj;      /* OOM kill score adjustment */
651         int oom_score_adj_min;  /* OOM kill score adjustment minimum value.
652                                  * Only settable by CAP_SYS_RESOURCE. */
653 
654         struct mutex cred_guard_mutex;  /* guard against foreign influences on
655                                          * credential calculations
656                                          * (notably. ptrace) */
657 };
658 
659 /* Context switch must be unlocked if interrupts are to be enabled */
660 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
661 # define __ARCH_WANT_UNLOCKED_CTXSW
662 #endif
663 
664 /*
665  * Bits in flags field of signal_struct.
666  */
667 #define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
668 #define SIGNAL_STOP_CONTINUED   0x00000002 /* SIGCONT since WCONTINUED reap */
669 #define SIGNAL_GROUP_EXIT       0x00000004 /* group exit in progress */
670 /*
671  * Pending notifications to parent.
672  */
673 #define SIGNAL_CLD_STOPPED      0x00000010
674 #define SIGNAL_CLD_CONTINUED    0x00000020
675 #define SIGNAL_CLD_MASK         (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
676 
677 #define SIGNAL_UNKILLABLE       0x00000040 /* for init: ignore fatal signals */
678 
679 /* If true, all threads except ->group_exit_task have pending SIGKILL */
680 static inline int signal_group_exit(const struct signal_struct *sig)
681 {
682         return  (sig->flags & SIGNAL_GROUP_EXIT) ||
683                 (sig->group_exit_task != NULL);
684 }
685 
686 /*
687  * Some day this will be a full-fledged user tracking system..
688  */
689 struct user_struct {
690         atomic_t __count;       /* reference count */
691         atomic_t processes;     /* How many processes does this user have? */
692         atomic_t files;         /* How many open files does this user have? */
693         atomic_t sigpending;    /* How many pending signals does this user have? */
694 #ifdef CONFIG_INOTIFY_USER
695         atomic_t inotify_watches; /* How many inotify watches does this user have? */
696         atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
697 #endif
698 #ifdef CONFIG_FANOTIFY
699         atomic_t fanotify_listeners;
700 #endif
701 #ifdef CONFIG_EPOLL
702         atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
703 #endif
704 #ifdef CONFIG_POSIX_MQUEUE
705         /* protected by mq_lock */
706         unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
707 #endif
708         unsigned long locked_shm; /* How many pages of mlocked shm ? */
709 
710 #ifdef CONFIG_KEYS
711         struct key *uid_keyring;        /* UID specific keyring */
712         struct key *session_keyring;    /* UID's default session keyring */
713 #endif
714 
715         /* Hash table maintenance information */
716         struct hlist_node uidhash_node;
717         uid_t uid;
718         struct user_namespace *user_ns;
719 
720 #ifdef CONFIG_PERF_EVENTS
721         atomic_long_t locked_vm;
722 #endif
723 };
724 
725 extern int uids_sysfs_init(void);
726 
727 extern struct user_struct *find_user(uid_t);
728 
729 extern struct user_struct root_user;
730 #define INIT_USER (&root_user)
731 
732 
733 struct backing_dev_info;
734 struct reclaim_state;
735 
736 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
737 struct sched_info {
738         /* cumulative counters */
739         unsigned long pcount;         /* # of times run on this cpu */
740         unsigned long long run_delay; /* time spent waiting on a runqueue */
741 
742         /* timestamps */
743         unsigned long long last_arrival,/* when we last ran on a cpu */
744                            last_queued; /* when we were last queued to run */
745 };
746 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
747 
748 #ifdef CONFIG_TASK_DELAY_ACCT
749 struct task_delay_info {
750         spinlock_t      lock;
751         unsigned int    flags;  /* Private per-task flags */
752 
753         /* For each stat XXX, add following, aligned appropriately
754          *
755          * struct timespec XXX_start, XXX_end;
756          * u64 XXX_delay;
757          * u32 XXX_count;
758          *
759          * Atomicity of updates to XXX_delay, XXX_count protected by
760          * single lock above (split into XXX_lock if contention is an issue).
761          */
762 
763         /*
764          * XXX_count is incremented on every XXX operation, the delay
765          * associated with the operation is added to XXX_delay.
766          * XXX_delay contains the accumulated delay time in nanoseconds.
767          */
768         struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
769         u64 blkio_delay;        /* wait for sync block io completion */
770         u64 swapin_delay;       /* wait for swapin block io completion */
771         u32 blkio_count;        /* total count of the number of sync block */
772                                 /* io operations performed */
773         u32 swapin_count;       /* total count of the number of swapin block */
774                                 /* io operations performed */
775 
776         struct timespec freepages_start, freepages_end;
777         u64 freepages_delay;    /* wait for memory reclaim */
778         u32 freepages_count;    /* total count of memory reclaim */
779 };
780 #endif  /* CONFIG_TASK_DELAY_ACCT */
781 
782 static inline int sched_info_on(void)
783 {
784 #ifdef CONFIG_SCHEDSTATS
785         return 1;
786 #elif defined(CONFIG_TASK_DELAY_ACCT)
787         extern int delayacct_on;
788         return delayacct_on;
789 #else
790         return 0;
791 #endif
792 }
793 
794 enum cpu_idle_type {
795         CPU_IDLE,
796         CPU_NOT_IDLE,
797         CPU_NEWLY_IDLE,
798         CPU_MAX_IDLE_TYPES
799 };
800 
801 /*
802  * Increase resolution of nice-level calculations for 64-bit architectures.
803  * The extra resolution improves shares distribution and load balancing of
804  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
805  * hierarchies, especially on larger systems. This is not a user-visible change
806  * and does not change the user-interface for setting shares/weights.
807  *
808  * We increase resolution only if we have enough bits to allow this increased
809  * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
810  * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
811  * increased costs.
812  */
813 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load  */
814 # define SCHED_LOAD_RESOLUTION  10
815 # define scale_load(w)          ((w) << SCHED_LOAD_RESOLUTION)
816 # define scale_load_down(w)     ((w) >> SCHED_LOAD_RESOLUTION)
817 #else
818 # define SCHED_LOAD_RESOLUTION  0
819 # define scale_load(w)          (w)
820 # define scale_load_down(w)     (w)
821 #endif
822 
823 #define SCHED_LOAD_SHIFT        (10 + SCHED_LOAD_RESOLUTION)
824 #define SCHED_LOAD_SCALE        (1L << SCHED_LOAD_SHIFT)
825 
826 /*
827  * Increase resolution of cpu_power calculations
828  */
829 #define SCHED_POWER_SHIFT       10
830 #define SCHED_POWER_SCALE       (1L << SCHED_POWER_SHIFT)
831 
832 /*
833  * sched-domains (multiprocessor balancing) declarations:
834  */
835 #ifdef CONFIG_SMP
836 #define SD_LOAD_BALANCE         0x0001  /* Do load balancing on this domain. */
837 #define SD_BALANCE_NEWIDLE      0x0002  /* Balance when about to become idle */
838 #define SD_BALANCE_EXEC         0x0004  /* Balance on exec */
839 #define SD_BALANCE_FORK         0x0008  /* Balance on fork, clone */
840 #define SD_BALANCE_WAKE         0x0010  /* Balance on wakeup */
841 #define SD_WAKE_AFFINE          0x0020  /* Wake task to waking CPU */
842 #define SD_PREFER_LOCAL         0x0040  /* Prefer to keep tasks local to this domain */
843 #define SD_SHARE_CPUPOWER       0x0080  /* Domain members share cpu power */
844 #define SD_POWERSAVINGS_BALANCE 0x0100  /* Balance for power savings */
845 #define SD_SHARE_PKG_RESOURCES  0x0200  /* Domain members share cpu pkg resources */
846 #define SD_SERIALIZE            0x0400  /* Only a single load balancing instance */
847 #define SD_ASYM_PACKING         0x0800  /* Place busy groups earlier in the domain */
848 #define SD_PREFER_SIBLING       0x1000  /* Prefer to place tasks in a sibling domain */
849 #define SD_OVERLAP              0x2000  /* sched_domains of this level overlap */
850 
851 enum powersavings_balance_level {
852         POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
853         POWERSAVINGS_BALANCE_BASIC,     /* Fill one thread/core/package
854                                          * first for long running threads
855                                          */
856         POWERSAVINGS_BALANCE_WAKEUP,    /* Also bias task wakeups to semi-idle
857                                          * cpu package for power savings
858                                          */
859         MAX_POWERSAVINGS_BALANCE_LEVELS
860 };
861 
862 extern int sched_mc_power_savings, sched_smt_power_savings;
863 
864 static inline int sd_balance_for_mc_power(void)
865 {
866         if (sched_smt_power_savings)
867                 return SD_POWERSAVINGS_BALANCE;
868 
869         if (!sched_mc_power_savings)
870                 return SD_PREFER_SIBLING;
871 
872         return 0;
873 }
874 
875 static inline int sd_balance_for_package_power(void)
876 {
877         if (sched_mc_power_savings | sched_smt_power_savings)
878                 return SD_POWERSAVINGS_BALANCE;
879 
880         return SD_PREFER_SIBLING;
881 }
882 
883 extern int __weak arch_sd_sibiling_asym_packing(void);
884 
885 /*
886  * Optimise SD flags for power savings:
887  * SD_BALANCE_NEWIDLE helps aggressive task consolidation and power savings.
888  * Keep default SD flags if sched_{smt,mc}_power_saving=0
889  */
890 
891 static inline int sd_power_saving_flags(void)
892 {
893         if (sched_mc_power_savings | sched_smt_power_savings)
894                 return SD_BALANCE_NEWIDLE;
895 
896         return 0;
897 }
898 
899 struct sched_group_power {
900         atomic_t ref;
901         /*
902          * CPU power of this group, SCHED_LOAD_SCALE being max power for a
903          * single CPU.
904          */
905         unsigned int power, power_orig;
906 };
907 
908 struct sched_group {
909         struct sched_group *next;       /* Must be a circular list */
910         atomic_t ref;
911 
912         unsigned int group_weight;
913         struct sched_group_power *sgp;
914 
915         /*
916          * The CPUs this group covers.
917          *
918          * NOTE: this field is variable length. (Allocated dynamically
919          * by attaching extra space to the end of the structure,
920          * depending on how many CPUs the kernel has booted up with)
921          */
922         unsigned long cpumask[0];
923 };
924 
925 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
926 {
927         return to_cpumask(sg->cpumask);
928 }
929 
930 struct sched_domain_attr {
931         int relax_domain_level;
932 };
933 
934 #define SD_ATTR_INIT    (struct sched_domain_attr) {    \
935         .relax_domain_level = -1,                       \
936 }
937 
938 extern int sched_domain_level_max;
939 
940 struct sched_domain {
941         /* These fields must be setup */
942         struct sched_domain *parent;    /* top domain must be null terminated */
943         struct sched_domain *child;     /* bottom domain must be null terminated */
944         struct sched_group *groups;     /* the balancing groups of the domain */
945         unsigned long min_interval;     /* Minimum balance interval ms */
946         unsigned long max_interval;     /* Maximum balance interval ms */
947         unsigned int busy_factor;       /* less balancing by factor if busy */
948         unsigned int imbalance_pct;     /* No balance until over watermark */
949         unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
950         unsigned int busy_idx;
951         unsigned int idle_idx;
952         unsigned int newidle_idx;
953         unsigned int wake_idx;
954         unsigned int forkexec_idx;
955         unsigned int smt_gain;
956         int flags;                      /* See SD_* */
957         int level;
958 
959         /* Runtime fields. */
960         unsigned long last_balance;     /* init to jiffies. units in jiffies */
961         unsigned int balance_interval;  /* initialise to 1. units in ms. */
962         unsigned int nr_balance_failed; /* initialise to 0 */
963 
964         u64 last_update;
965 
966 #ifdef CONFIG_SCHEDSTATS
967         /* load_balance() stats */
968         unsigned int lb_count[CPU_MAX_IDLE_TYPES];
969         unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
970         unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
971         unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
972         unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
973         unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
974         unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
975         unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
976 
977         /* Active load balancing */
978         unsigned int alb_count;
979         unsigned int alb_failed;
980         unsigned int alb_pushed;
981 
982         /* SD_BALANCE_EXEC stats */
983         unsigned int sbe_count;
984         unsigned int sbe_balanced;
985         unsigned int sbe_pushed;
986 
987         /* SD_BALANCE_FORK stats */
988         unsigned int sbf_count;
989         unsigned int sbf_balanced;
990         unsigned int sbf_pushed;
991 
992         /* try_to_wake_up() stats */
993         unsigned int ttwu_wake_remote;
994         unsigned int ttwu_move_affine;
995         unsigned int ttwu_move_balance;
996 #endif
997 #ifdef CONFIG_SCHED_DEBUG
998         char *name;
999 #endif
1000         union {
1001                 void *private;          /* used during construction */
1002                 struct rcu_head rcu;    /* used during destruction */
1003         };
1004 
1005         unsigned int span_weight;
1006         /*
1007          * Span of all CPUs in this domain.
1008          *
1009          * NOTE: this field is variable length. (Allocated dynamically
1010          * by attaching extra space to the end of the structure,
1011          * depending on how many CPUs the kernel has booted up with)
1012          */
1013         unsigned long span[0];
1014 };
1015 
1016 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1017 {
1018         return to_cpumask(sd->span);
1019 }
1020 
1021 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1022                                     struct sched_domain_attr *dattr_new);
1023 
1024 /* Allocate an array of sched domains, for partition_sched_domains(). */
1025 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1026 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1027 
1028 /* Test a flag in parent sched domain */
1029 static inline int test_sd_parent(struct sched_domain *sd, int flag)
1030 {
1031         if (sd->parent && (sd->parent->flags & flag))
1032                 return 1;
1033 
1034         return 0;
1035 }
1036 
1037 unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
1038 unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
1039 
1040 #else /* CONFIG_SMP */
1041 
1042 struct sched_domain_attr;
1043 
1044 static inline void
1045 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1046                         struct sched_domain_attr *dattr_new)
1047 {
1048 }
1049 #endif  /* !CONFIG_SMP */
1050 
1051 
1052 struct io_context;                      /* See blkdev.h */
1053 
1054 
1055 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1056 extern void prefetch_stack(struct task_struct *t);
1057 #else
1058 static inline void prefetch_stack(struct task_struct *t) { }
1059 #endif
1060 
1061 struct audit_context;           /* See audit.c */
1062 struct mempolicy;
1063 struct pipe_inode_info;
1064 struct uts_namespace;
1065 
1066 struct rq;
1067 struct sched_domain;
1068 
1069 /*
1070  * wake flags
1071  */
1072 #define WF_SYNC         0x01            /* waker goes to sleep after wakup */
1073 #define WF_FORK         0x02            /* child wakeup after fork */
1074 #define WF_MIGRATED     0x04            /* internal use, task got migrated */
1075 
1076 #define ENQUEUE_WAKEUP          1
1077 #define ENQUEUE_HEAD            2
1078 #ifdef CONFIG_SMP
1079 #define ENQUEUE_WAKING          4       /* sched_class::task_waking was called */
1080 #else
1081 #define ENQUEUE_WAKING          0
1082 #endif
1083 
1084 #define DEQUEUE_SLEEP           1
1085 
1086 struct sched_class {
1087         const struct sched_class *next;
1088 
1089         void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1090         void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1091         void (*yield_task) (struct rq *rq);
1092         bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1093 
1094         void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1095 
1096         struct task_struct * (*pick_next_task) (struct rq *rq);
1097         void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1098 
1099 #ifdef CONFIG_SMP
1100         int  (*select_task_rq)(struct task_struct *p, int sd_flag, int flags);
1101 
1102         void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1103         void (*post_schedule) (struct rq *this_rq);
1104         void (*task_waking) (struct task_struct *task);
1105         void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1106 
1107         void (*set_cpus_allowed)(struct task_struct *p,
1108                                  const struct cpumask *newmask);
1109 
1110         void (*rq_online)(struct rq *rq);
1111         void (*rq_offline)(struct rq *rq);
1112 #endif
1113 
1114         void (*set_curr_task) (struct rq *rq);
1115         void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1116         void (*task_fork) (struct task_struct *p);
1117 
1118         void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1119         void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1120         void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1121                              int oldprio);
1122 
1123         unsigned int (*get_rr_interval) (struct rq *rq,
1124                                          struct task_struct *task);
1125 
1126 #ifdef CONFIG_FAIR_GROUP_SCHED
1127         void (*task_move_group) (struct task_struct *p, int on_rq);
1128 #endif
1129 };
1130 
1131 struct load_weight {
1132         unsigned long weight, inv_weight;
1133 };
1134 
1135 #ifdef CONFIG_SCHEDSTATS
1136 struct sched_statistics {
1137         u64                     wait_start;
1138         u64                     wait_max;
1139         u64                     wait_count;
1140         u64                     wait_sum;
1141         u64                     iowait_count;
1142         u64                     iowait_sum;
1143 
1144         u64                     sleep_start;
1145         u64                     sleep_max;
1146         s64                     sum_sleep_runtime;
1147 
1148         u64                     block_start;
1149         u64                     block_max;
1150         u64                     exec_max;
1151         u64                     slice_max;
1152 
1153         u64                     nr_migrations_cold;
1154         u64                     nr_failed_migrations_affine;
1155         u64                     nr_failed_migrations_running;
1156         u64                     nr_failed_migrations_hot;
1157         u64                     nr_forced_migrations;
1158 
1159         u64                     nr_wakeups;
1160         u64                     nr_wakeups_sync;
1161         u64                     nr_wakeups_migrate;
1162         u64                     nr_wakeups_local;
1163         u64                     nr_wakeups_remote;
1164         u64                     nr_wakeups_affine;
1165         u64                     nr_wakeups_affine_attempts;
1166         u64                     nr_wakeups_passive;
1167         u64                     nr_wakeups_idle;
1168 };
1169 #endif
1170 
1171 struct sched_entity {
1172         struct load_weight      load;           /* for load-balancing */
1173         struct rb_node          run_node;
1174         struct list_head        group_node;
1175         unsigned int            on_rq;
1176 
1177         u64                     exec_start;
1178         u64                     sum_exec_runtime;
1179         u64                     vruntime;
1180         u64                     prev_sum_exec_runtime;
1181 
1182         u64                     nr_migrations;
1183 
1184 #ifdef CONFIG_SCHEDSTATS
1185         struct sched_statistics statistics;
1186 #endif
1187 
1188 #ifdef CONFIG_FAIR_GROUP_SCHED
1189         struct sched_entity     *parent;
1190         /* rq on which this entity is (to be) queued: */
1191         struct cfs_rq           *cfs_rq;
1192         /* rq "owned" by this entity/group: */
1193         struct cfs_rq           *my_q;
1194 #endif
1195 };
1196 
1197 struct sched_rt_entity {
1198         struct list_head run_list;
1199         unsigned long timeout;
1200         unsigned int time_slice;
1201         int nr_cpus_allowed;
1202 
1203         struct sched_rt_entity *back;
1204 #ifdef CONFIG_RT_GROUP_SCHED
1205         struct sched_rt_entity  *parent;
1206         /* rq on which this entity is (to be) queued: */
1207         struct rt_rq            *rt_rq;
1208         /* rq "owned" by this entity/group: */
1209         struct rt_rq            *my_q;
1210 #endif
1211 };
1212 
1213 struct rcu_node;
1214 
1215 enum perf_event_task_context {
1216         perf_invalid_context = -1,
1217         perf_hw_context = 0,
1218         perf_sw_context,
1219         perf_nr_task_contexts,
1220 };
1221 
1222 struct task_struct {
1223         volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
1224         void *stack;
1225         atomic_t usage;
1226         unsigned int flags;     /* per process flags, defined below */
1227         unsigned int ptrace;
1228 
1229 #ifdef CONFIG_SMP
1230         struct task_struct *wake_entry;
1231         int on_cpu;
1232 #endif
1233         int on_rq;
1234 
1235         int prio, static_prio, normal_prio;
1236         unsigned int rt_priority;
1237         const struct sched_class *sched_class;
1238         struct sched_entity se;
1239         struct sched_rt_entity rt;
1240 #ifdef CONFIG_CGROUP_SCHED
1241         struct task_group *sched_task_group;
1242 #endif
1243 
1244 #ifdef CONFIG_PREEMPT_NOTIFIERS
1245         /* list of struct preempt_notifier: */
1246         struct hlist_head preempt_notifiers;
1247 #endif
1248 
1249         /*
1250          * fpu_counter contains the number of consecutive context switches
1251          * that the FPU is used. If this is over a threshold, the lazy fpu
1252          * saving becomes unlazy to save the trap. This is an unsigned char
1253          * so that after 256 times the counter wraps and the behavior turns
1254          * lazy again; this to deal with bursty apps that only use FPU for
1255          * a short time
1256          */
1257         unsigned char fpu_counter;
1258 #ifdef CONFIG_BLK_DEV_IO_TRACE
1259         unsigned int btrace_seq;
1260 #endif
1261 
1262         unsigned int policy;
1263         cpumask_t cpus_allowed;
1264 
1265 #ifdef CONFIG_PREEMPT_RCU
1266         int rcu_read_lock_nesting;
1267         char rcu_read_unlock_special;
1268 #if defined(CONFIG_RCU_BOOST) && defined(CONFIG_TREE_PREEMPT_RCU)
1269         int rcu_boosted;
1270 #endif /* #if defined(CONFIG_RCU_BOOST) && defined(CONFIG_TREE_PREEMPT_RCU) */
1271         struct list_head rcu_node_entry;
1272 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1273 #ifdef CONFIG_TREE_PREEMPT_RCU
1274         struct rcu_node *rcu_blocked_node;
1275 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1276 #ifdef CONFIG_RCU_BOOST
1277         struct rt_mutex *rcu_boost_mutex;
1278 #endif /* #ifdef CONFIG_RCU_BOOST */
1279 
1280 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1281         struct sched_info sched_info;
1282 #endif
1283 
1284         struct list_head tasks;
1285 #ifdef CONFIG_SMP
1286         struct plist_node pushable_tasks;
1287 #endif
1288 
1289         struct mm_struct *mm, *active_mm;
1290 #ifdef CONFIG_COMPAT_BRK
1291         unsigned brk_randomized:1;
1292 #endif
1293 #if defined(SPLIT_RSS_COUNTING)
1294         struct task_rss_stat    rss_stat;
1295 #endif
1296 /* task state */
1297         int exit_state;
1298         int exit_code, exit_signal;
1299         int pdeath_signal;  /*  The signal sent when the parent dies  */
1300         unsigned int group_stop;        /* GROUP_STOP_*, siglock protected */
1301         /* ??? */
1302         unsigned int personality;
1303         unsigned did_exec:1;
1304         unsigned in_execve:1;   /* Tell the LSMs that the process is doing an
1305                                  * execve */
1306         unsigned in_iowait:1;
1307 
1308 
1309         /* Revert to default priority/policy when forking */
1310         unsigned sched_reset_on_fork:1;
1311         unsigned sched_contributes_to_load:1;
1312 
1313         pid_t pid;
1314         pid_t tgid;
1315 
1316 #ifdef CONFIG_CC_STACKPROTECTOR
1317         /* Canary value for the -fstack-protector gcc feature */
1318         unsigned long stack_canary;
1319 #endif
1320 
1321         /* 
1322          * pointers to (original) parent process, youngest child, younger sibling,
1323          * older sibling, respectively.  (p->father can be replaced with 
1324          * p->real_parent->pid)
1325          */
1326         struct task_struct *real_parent; /* real parent process */
1327         struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1328         /*
1329          * children/sibling forms the list of my natural children
1330          */
1331         struct list_head children;      /* list of my children */
1332         struct list_head sibling;       /* linkage in my parent's children list */
1333         struct task_struct *group_leader;       /* threadgroup leader */
1334 
1335         /*
1336          * ptraced is the list of tasks this task is using ptrace on.
1337          * This includes both natural children and PTRACE_ATTACH targets.
1338          * p->ptrace_entry is p's link on the p->parent->ptraced list.
1339          */
1340         struct list_head ptraced;
1341         struct list_head ptrace_entry;
1342 
1343         /* PID/PID hash table linkage. */
1344         struct pid_link pids[PIDTYPE_MAX];
1345         struct list_head thread_group;
1346 
1347         struct completion *vfork_done;          /* for vfork() */
1348         int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
1349         int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
1350 
1351         cputime_t utime, stime, utimescaled, stimescaled;
1352         cputime_t gtime;
1353 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
1354         cputime_t prev_utime, prev_stime;
1355 #endif
1356         unsigned long nvcsw, nivcsw; /* context switch counts */
1357         struct timespec start_time;             /* monotonic time */
1358         struct timespec real_start_time;        /* boot based time */
1359 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1360         unsigned long min_flt, maj_flt;
1361 
1362         struct task_cputime cputime_expires;
1363         struct list_head cpu_timers[3];
1364 
1365 /* process credentials */
1366         const struct cred __rcu *real_cred; /* objective and real subjective task
1367                                          * credentials (COW) */
1368         const struct cred __rcu *cred;  /* effective (overridable) subjective task
1369                                          * credentials (COW) */
1370         struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1371 
1372         char comm[TASK_COMM_LEN]; /* executable name excluding path
1373                                      - access with [gs]et_task_comm (which lock
1374                                        it with task_lock())
1375                                      - initialized normally by setup_new_exec */
1376 /* file system info */
1377         int link_count, total_link_count;
1378 #ifdef CONFIG_SYSVIPC
1379 /* ipc stuff */
1380         struct sysv_sem sysvsem;
1381 #endif
1382 #ifdef CONFIG_DETECT_HUNG_TASK
1383 /* hung task detection */
1384         unsigned long last_switch_count;
1385 #endif
1386 /* CPU-specific state of this task */
1387         struct thread_struct thread;
1388 /* filesystem information */
1389         struct fs_struct *fs;
1390 /* open file information */
1391         struct files_struct *files;
1392 /* namespaces */
1393         struct nsproxy *nsproxy;
1394 /* signal handlers */
1395         struct signal_struct *signal;
1396         struct sighand_struct *sighand;
1397 
1398         sigset_t blocked, real_blocked;
1399         sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1400         struct sigpending pending;
1401 
1402         unsigned long sas_ss_sp;
1403         size_t sas_ss_size;
1404         int (*notifier)(void *priv);
1405         void *notifier_data;
1406         sigset_t *notifier_mask;
1407         struct audit_context *audit_context;
1408 #ifdef CONFIG_AUDITSYSCALL
1409         uid_t loginuid;
1410         unsigned int sessionid;
1411 #endif
1412         seccomp_t seccomp;
1413 
1414 /* Thread group tracking */
1415         u32 parent_exec_id;
1416         u32 self_exec_id;
1417 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1418  * mempolicy */
1419         spinlock_t alloc_lock;
1420 
1421 #ifdef CONFIG_GENERIC_HARDIRQS
1422         /* IRQ handler threads */
1423         struct irqaction *irqaction;
1424 #endif
1425 
1426         /* Protection of the PI data structures: */
1427         raw_spinlock_t pi_lock;
1428 
1429 #ifdef CONFIG_RT_MUTEXES
1430         /* PI waiters blocked on a rt_mutex held by this task */
1431         struct plist_head pi_waiters;
1432         /* Deadlock detection and priority inheritance handling */
1433         struct rt_mutex_waiter *pi_blocked_on;
1434 #endif
1435 
1436 #ifdef CONFIG_DEBUG_MUTEXES
1437         /* mutex deadlock detection */
1438         struct mutex_waiter *blocked_on;
1439 #endif
1440 #ifdef CONFIG_TRACE_IRQFLAGS
1441         unsigned int irq_events;
1442         unsigned long hardirq_enable_ip;
1443         unsigned long hardirq_disable_ip;
1444         unsigned int hardirq_enable_event;
1445         unsigned int hardirq_disable_event;
1446         int hardirqs_enabled;
1447         int hardirq_context;
1448         unsigned long softirq_disable_ip;
1449         unsigned long softirq_enable_ip;
1450         unsigned int softirq_disable_event;
1451         unsigned int softirq_enable_event;
1452         int softirqs_enabled;
1453         int softirq_context;
1454 #endif
1455 #ifdef CONFIG_LOCKDEP
1456 # define MAX_LOCK_DEPTH 48UL
1457         u64 curr_chain_key;
1458         int lockdep_depth;
1459         unsigned int lockdep_recursion;
1460         struct held_lock held_locks[MAX_LOCK_DEPTH];
1461         gfp_t lockdep_reclaim_gfp;
1462 #endif
1463 
1464 /* journalling filesystem info */
1465         void *journal_info;
1466 
1467 /* stacked block device info */
1468         struct bio_list *bio_list;
1469 
1470 #ifdef CONFIG_BLOCK
1471 /* stack plugging */
1472         struct blk_plug *plug;
1473 #endif
1474 
1475 /* VM state */
1476         struct reclaim_state *reclaim_state;
1477 
1478         struct backing_dev_info *backing_dev_info;
1479 
1480         struct io_context *io_context;
1481 
1482         unsigned long ptrace_message;
1483         siginfo_t *last_siginfo; /* For ptrace use.  */
1484         struct task_io_accounting ioac;
1485 #if defined(CONFIG_TASK_XACCT)
1486         u64 acct_rss_mem1;      /* accumulated rss usage */
1487         u64 acct_vm_mem1;       /* accumulated virtual memory usage */
1488         cputime_t acct_timexpd; /* stime + utime since last update */
1489 #endif
1490 #ifdef CONFIG_CPUSETS
1491         nodemask_t mems_allowed;        /* Protected by alloc_lock */
1492         seqcount_t mems_allowed_seq;    /* Seqence no to catch updates */
1493         int cpuset_mem_spread_rotor;
1494         int cpuset_slab_spread_rotor;
1495 #endif
1496 #ifdef CONFIG_CGROUPS
1497         /* Control Group info protected by css_set_lock */
1498         struct css_set __rcu *cgroups;
1499         /* cg_list protected by css_set_lock and tsk->alloc_lock */
1500         struct list_head cg_list;
1501 #endif
1502 #ifdef CONFIG_FUTEX
1503         struct robust_list_head __user *robust_list;
1504 #ifdef CONFIG_COMPAT
1505         struct compat_robust_list_head __user *compat_robust_list;
1506 #endif
1507         struct list_head pi_state_list;
1508         struct futex_pi_state *pi_state_cache;
1509 #endif
1510 #ifdef CONFIG_PERF_EVENTS
1511         struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1512         struct mutex perf_event_mutex;
1513         struct list_head perf_event_list;
1514 #endif
1515 #ifdef CONFIG_NUMA
1516         struct mempolicy *mempolicy;    /* Protected by alloc_lock */
1517         short il_next;
1518         short pref_node_fork;
1519 #endif
1520         atomic_t fs_excl;       /* holding fs exclusive resources */
1521         struct rcu_head rcu;
1522 
1523         /*
1524          * cache last used pipe for splice
1525          */
1526         struct pipe_inode_info *splice_pipe;
1527 #ifdef  CONFIG_TASK_DELAY_ACCT
1528         struct task_delay_info *delays;
1529 #endif
1530 #ifdef CONFIG_FAULT_INJECTION
1531         int make_it_fail;
1532 #endif
1533         struct prop_local_single dirties;
1534 #ifdef CONFIG_LATENCYTOP
1535         int latency_record_count;
1536         struct latency_record latency_record[LT_SAVECOUNT];
1537 #endif
1538         /*
1539          * time slack values; these are used to round up poll() and
1540          * select() etc timeout values. These are in nanoseconds.
1541          */
1542         unsigned long timer_slack_ns;
1543         unsigned long default_timer_slack_ns;
1544 
1545         struct list_head        *scm_work_list;
1546 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1547         /* Index of current stored address in ret_stack */
1548         int curr_ret_stack;
1549         /* Stack of return addresses for return function tracing */
1550         struct ftrace_ret_stack *ret_stack;
1551         /* time stamp for last schedule */
1552         unsigned long long ftrace_timestamp;
1553         /*
1554          * Number of functions that haven't been traced
1555          * because of depth overrun.
1556          */
1557         atomic_t trace_overrun;
1558         /* Pause for the tracing */
1559         atomic_t tracing_graph_pause;
1560 #endif
1561 #ifdef CONFIG_TRACING
1562         /* state flags for use by tracers */
1563         unsigned long trace;
1564         /* bitmask and counter of trace recursion */
1565         unsigned long trace_recursion;
1566 #endif /* CONFIG_TRACING */
1567 #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1568         struct memcg_batch_info {
1569                 int do_batch;   /* incremented when batch uncharge started */
1570                 struct mem_cgroup *memcg; /* target memcg of uncharge */
1571                 unsigned long nr_pages; /* uncharged usage */
1572                 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
1573         } memcg_batch;
1574 #endif
1575 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1576         atomic_t ptrace_bp_refcnt;
1577 #endif
1578 #if defined(CONFIG_CCSECURITY) && !defined(CONFIG_CCSECURITY_USE_EXTERNAL_TASK_SECURITY)
1579         struct ccs_domain_info *ccs_domain_info;
1580         u32 ccs_flags;
1581 #endif
1582 };
1583 
1584 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1585 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1586 
1587 /*
1588  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1589  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1590  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1591  * values are inverted: lower p->prio value means higher priority.
1592  *
1593  * The MAX_USER_RT_PRIO value allows the actual maximum
1594  * RT priority to be separate from the value exported to
1595  * user-space.  This allows kernel threads to set their
1596  * priority to a value higher than any user task. Note:
1597  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1598  */
1599 
1600 #define MAX_USER_RT_PRIO        100
1601 #define MAX_RT_PRIO             MAX_USER_RT_PRIO
1602 
1603 #define MAX_PRIO                (MAX_RT_PRIO + 40)
1604 #define DEFAULT_PRIO            (MAX_RT_PRIO + 20)
1605 
1606 static inline int rt_prio(int prio)
1607 {
1608         if (unlikely(prio < MAX_RT_PRIO))
1609                 return 1;
1610         return 0;
1611 }
1612 
1613 static inline int rt_task(struct task_struct *p)
1614 {
1615         return rt_prio(p->prio);
1616 }
1617 
1618 static inline struct pid *task_pid(struct task_struct *task)
1619 {
1620         return task->pids[PIDTYPE_PID].pid;
1621 }
1622 
1623 static inline struct pid *task_tgid(struct task_struct *task)
1624 {
1625         return task->group_leader->pids[PIDTYPE_PID].pid;
1626 }
1627 
1628 /*
1629  * Without tasklist or rcu lock it is not safe to dereference
1630  * the result of task_pgrp/task_session even if task == current,
1631  * we can race with another thread doing sys_setsid/sys_setpgid.
1632  */
1633 static inline struct pid *task_pgrp(struct task_struct *task)
1634 {
1635         return task->group_leader->pids[PIDTYPE_PGID].pid;
1636 }
1637 
1638 static inline struct pid *task_session(struct task_struct *task)
1639 {
1640         return task->group_leader->pids[PIDTYPE_SID].pid;
1641 }
1642 
1643 struct pid_namespace;
1644 
1645 /*
1646  * the helpers to get the task's different pids as they are seen
1647  * from various namespaces
1648  *
1649  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1650  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1651  *                     current.
1652  * task_xid_nr_ns()  : id seen from the ns specified;
1653  *
1654  * set_task_vxid()   : assigns a virtual id to a task;
1655  *
1656  * see also pid_nr() etc in include/linux/pid.h
1657  */
1658 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1659                         struct pid_namespace *ns);
1660 
1661 static inline pid_t task_pid_nr(struct task_struct *tsk)
1662 {
1663         return tsk->pid;
1664 }
1665 
1666 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1667                                         struct pid_namespace *ns)
1668 {
1669         return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1670 }
1671 
1672 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1673 {
1674         return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1675 }
1676 
1677 
1678 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1679 {
1680         return tsk->tgid;
1681 }
1682 
1683 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1684 
1685 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1686 {
1687         return pid_vnr(task_tgid(tsk));
1688 }
1689 
1690 
1691 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1692                                         struct pid_namespace *ns)
1693 {
1694         return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1695 }
1696 
1697 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1698 {
1699         return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1700 }
1701 
1702 
1703 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1704                                         struct pid_namespace *ns)
1705 {
1706         return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1707 }
1708 
1709 static inline pid_t task_session_vnr(struct task_struct *tsk)
1710 {
1711         return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1712 }
1713 
1714 /* obsolete, do not use */
1715 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1716 {
1717         return task_pgrp_nr_ns(tsk, &init_pid_ns);
1718 }
1719 
1720 /**
1721  * pid_alive - check that a task structure is not stale
1722  * @p: Task structure to be checked.
1723  *
1724  * Test if a process is not yet dead (at most zombie state)
1725  * If pid_alive fails, then pointers within the task structure
1726  * can be stale and must not be dereferenced.
1727  */
1728 static inline int pid_alive(struct task_struct *p)
1729 {
1730         return p->pids[PIDTYPE_PID].pid != NULL;
1731 }
1732 
1733 /**
1734  * is_global_init - check if a task structure is init
1735  * @tsk: Task structure to be checked.
1736  *
1737  * Check if a task structure is the first user space task the kernel created.
1738  */
1739 static inline int is_global_init(struct task_struct *tsk)
1740 {
1741         return tsk->pid == 1;
1742 }
1743 
1744 /*
1745  * is_container_init:
1746  * check whether in the task is init in its own pid namespace.
1747  */
1748 extern int is_container_init(struct task_struct *tsk);
1749 
1750 extern struct pid *cad_pid;
1751 
1752 extern void free_task(struct task_struct *tsk);
1753 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1754 
1755 extern void __put_task_struct(struct task_struct *t);
1756 
1757 static inline void put_task_struct(struct task_struct *t)
1758 {
1759         if (atomic_dec_and_test(&t->usage))
1760                 __put_task_struct(t);
1761 }
1762 
1763 extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1764 extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1765 
1766 /*
1767  * Per process flags
1768  */
1769 #define PF_STARTING     0x00000002      /* being created */
1770 #define PF_EXITING      0x00000004      /* getting shut down */
1771 #define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
1772 #define PF_VCPU         0x00000010      /* I'm a virtual CPU */
1773 #define PF_WQ_WORKER    0x00000020      /* I'm a workqueue worker */
1774 #define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
1775 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1776 #define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
1777 #define PF_DUMPCORE     0x00000200      /* dumped core */
1778 #define PF_SIGNALED     0x00000400      /* killed by a signal */
1779 #define PF_MEMALLOC     0x00000800      /* Allocating memory */
1780 #define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
1781 #define PF_FREEZING     0x00004000      /* freeze in progress. do not account to load */
1782 #define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
1783 #define PF_FROZEN       0x00010000      /* frozen for system suspend */
1784 #define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
1785 #define PF_KSWAPD       0x00040000      /* I am kswapd */
1786 #define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
1787 #define PF_KTHREAD      0x00200000      /* I am a kernel thread */
1788 #define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
1789 #define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
1790 #define PF_SPREAD_PAGE  0x01000000      /* Spread page cache over cpuset */
1791 #define PF_SPREAD_SLAB  0x02000000      /* Spread some slab caches over cpuset */
1792 #define PF_THREAD_BOUND 0x04000000      /* Thread bound to specific cpu */
1793 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1794 #define PF_MEMPOLICY    0x10000000      /* Non-default NUMA mempolicy */
1795 #define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
1796 #define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezable */
1797 #define PF_FREEZER_NOSIG 0x80000000     /* Freezer won't send signals to it */
1798 
1799 /*
1800  * Only the _current_ task can read/write to tsk->flags, but other
1801  * tasks can access tsk->flags in readonly mode for example
1802  * with tsk_used_math (like during threaded core dumping).
1803  * There is however an exception to this rule during ptrace
1804  * or during fork: the ptracer task is allowed to write to the
1805  * child->flags of its traced child (same goes for fork, the parent
1806  * can write to the child->flags), because we're guaranteed the
1807  * child is not running and in turn not changing child->flags
1808  * at the same time the parent does it.
1809  */
1810 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1811 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1812 #define clear_used_math() clear_stopped_child_used_math(current)
1813 #define set_used_math() set_stopped_child_used_math(current)
1814 #define conditional_stopped_child_used_math(condition, child) \
1815         do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1816 #define conditional_used_math(condition) \
1817         conditional_stopped_child_used_math(condition, current)
1818 #define copy_to_stopped_child_used_math(child) \
1819         do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1820 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1821 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1822 #define used_math() tsk_used_math(current)
1823 
1824 /*
1825  * task->group_stop flags
1826  */
1827 #define GROUP_STOP_SIGMASK      0xffff    /* signr of the last group stop */
1828 #define GROUP_STOP_PENDING      (1 << 16) /* task should stop for group stop */
1829 #define GROUP_STOP_CONSUME      (1 << 17) /* consume group stop count */
1830 #define GROUP_STOP_TRAPPING     (1 << 18) /* switching from STOPPED to TRACED */
1831 #define GROUP_STOP_DEQUEUED     (1 << 19) /* stop signal dequeued */
1832 
1833 extern void task_clear_group_stop_pending(struct task_struct *task);
1834 
1835 #ifdef CONFIG_PREEMPT_RCU
1836 
1837 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1838 #define RCU_READ_UNLOCK_BOOSTED (1 << 1) /* boosted while in RCU read-side. */
1839 #define RCU_READ_UNLOCK_NEED_QS (1 << 2) /* RCU core needs CPU response. */
1840 
1841 static inline void rcu_copy_process(struct task_struct *p)
1842 {
1843         p->rcu_read_lock_nesting = 0;
1844         p->rcu_read_unlock_special = 0;
1845 #ifdef CONFIG_TREE_PREEMPT_RCU
1846         p->rcu_blocked_node = NULL;
1847 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1848 #ifdef CONFIG_RCU_BOOST
1849         p->rcu_boost_mutex = NULL;
1850 #endif /* #ifdef CONFIG_RCU_BOOST */
1851         INIT_LIST_HEAD(&p->rcu_node_entry);
1852 }
1853 
1854 #else
1855 
1856 static inline void rcu_copy_process(struct task_struct *p)
1857 {
1858 }
1859 
1860 #endif
1861 
1862 #ifdef CONFIG_SMP
1863 extern void do_set_cpus_allowed(struct task_struct *p,
1864                                const struct cpumask *new_mask);
1865 
1866 extern int set_cpus_allowed_ptr(struct task_struct *p,
1867                                 const struct cpumask *new_mask);
1868 #else
1869 static inline void do_set_cpus_allowed(struct task_struct *p,
1870                                       const struct cpumask *new_mask)
1871 {
1872 }
1873 static inline int set_cpus_allowed_ptr(struct task_struct *p,
1874                                        const struct cpumask *new_mask)
1875 {
1876         if (!cpumask_test_cpu(0, new_mask))
1877                 return -EINVAL;
1878         return 0;
1879 }
1880 #endif
1881 
1882 #ifndef CONFIG_CPUMASK_OFFSTACK
1883 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1884 {
1885         return set_cpus_allowed_ptr(p, &new_mask);
1886 }
1887 #endif
1888 
1889 /*
1890  * Do not use outside of architecture code which knows its limitations.
1891  *
1892  * sched_clock() has no promise of monotonicity or bounded drift between
1893  * CPUs, use (which you should not) requires disabling IRQs.
1894  *
1895  * Please use one of the three interfaces below.
1896  */
1897 extern unsigned long long notrace sched_clock(void);
1898 /*
1899  * See the comment in kernel/sched_clock.c
1900  */
1901 extern u64 cpu_clock(int cpu);
1902 extern u64 local_clock(void);
1903 extern u64 sched_clock_cpu(int cpu);
1904 
1905 
1906 extern void sched_clock_init(void);
1907 
1908 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1909 static inline void sched_clock_tick(void)
1910 {
1911 }
1912 
1913 static inline void sched_clock_idle_sleep_event(void)
1914 {
1915 }
1916 
1917 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1918 {
1919 }
1920 #else
1921 /*
1922  * Architectures can set this to 1 if they have specified
1923  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1924  * but then during bootup it turns out that sched_clock()
1925  * is reliable after all:
1926  */
1927 extern int sched_clock_stable;
1928 
1929 extern void sched_clock_tick(void);
1930 extern void sched_clock_idle_sleep_event(void);
1931 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1932 #endif
1933 
1934 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1935 /*
1936  * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
1937  * The reason for this explicit opt-in is not to have perf penalty with
1938  * slow sched_clocks.
1939  */
1940 extern void enable_sched_clock_irqtime(void);
1941 extern void disable_sched_clock_irqtime(void);
1942 #else
1943 static inline void enable_sched_clock_irqtime(void) {}
1944 static inline void disable_sched_clock_irqtime(void) {}
1945 #endif
1946 
1947 extern unsigned long long
1948 task_sched_runtime(struct task_struct *task);
1949 
1950 /* sched_exec is called by processes performing an exec */
1951 #ifdef CONFIG_SMP
1952 extern void sched_exec(void);
1953 #else
1954 #define sched_exec()   {}
1955 #endif
1956 
1957 extern void sched_clock_idle_sleep_event(void);
1958 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1959 
1960 #ifdef CONFIG_HOTPLUG_CPU
1961 extern void idle_task_exit(void);
1962 #else
1963 static inline void idle_task_exit(void) {}
1964 #endif
1965 
1966 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1967 extern void wake_up_idle_cpu(int cpu);
1968 #else
1969 static inline void wake_up_idle_cpu(int cpu) { }
1970 #endif
1971 
1972 extern unsigned int sysctl_sched_latency;
1973 extern unsigned int sysctl_sched_min_granularity;
1974 extern unsigned int sysctl_sched_wakeup_granularity;
1975 extern unsigned int sysctl_sched_child_runs_first;
1976 
1977 enum sched_tunable_scaling {
1978         SCHED_TUNABLESCALING_NONE,
1979         SCHED_TUNABLESCALING_LOG,
1980         SCHED_TUNABLESCALING_LINEAR,
1981         SCHED_TUNABLESCALING_END,
1982 };
1983 extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1984 
1985 #ifdef CONFIG_SCHED_DEBUG
1986 extern unsigned int sysctl_sched_migration_cost;
1987 extern unsigned int sysctl_sched_nr_migrate;
1988 extern unsigned int sysctl_sched_time_avg;
1989 extern unsigned int sysctl_timer_migration;
1990 extern unsigned int sysctl_sched_shares_window;
1991 
1992 int sched_proc_update_handler(struct ctl_table *table, int write,
1993                 void __user *buffer, size_t *length,
1994                 loff_t *ppos);
1995 #endif
1996 #ifdef CONFIG_SCHED_DEBUG
1997 static inline unsigned int get_sysctl_timer_migration(void)
1998 {
1999         return sysctl_timer_migration;
2000 }
2001 #else
2002 static inline unsigned int get_sysctl_timer_migration(void)
2003 {
2004         return 1;
2005 }
2006 #endif
2007 extern unsigned int sysctl_sched_rt_period;
2008 extern int sysctl_sched_rt_runtime;
2009 
2010 int sched_rt_handler(struct ctl_table *table, int write,
2011                 void __user *buffer, size_t *lenp,
2012                 loff_t *ppos);
2013 
2014 #ifdef CONFIG_SCHED_AUTOGROUP
2015 extern unsigned int sysctl_sched_autogroup_enabled;
2016 
2017 extern void sched_autogroup_create_attach(struct task_struct *p);
2018 extern void sched_autogroup_detach(struct task_struct *p);
2019 extern void sched_autogroup_fork(struct signal_struct *sig);
2020 extern void sched_autogroup_exit(struct signal_struct *sig);
2021 #ifdef CONFIG_PROC_FS
2022 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2023 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice);
2024 #endif
2025 #else
2026 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2027 static inline void sched_autogroup_detach(struct task_struct *p) { }
2028 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2029 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2030 #endif
2031 
2032 #ifdef CONFIG_RT_MUTEXES
2033 extern int rt_mutex_getprio(struct task_struct *p);
2034 extern void rt_mutex_setprio(struct task_struct *p, int prio);
2035 extern void rt_mutex_adjust_pi(struct task_struct *p);
2036 #else
2037 static inline int rt_mutex_getprio(struct task_struct *p)
2038 {
2039         return p->normal_prio;
2040 }
2041 # define rt_mutex_adjust_pi(p)          do { } while (0)
2042 #endif
2043 
2044 extern bool yield_to(struct task_struct *p, bool preempt);
2045 extern void set_user_nice(struct task_struct *p, long nice);
2046 extern int task_prio(const struct task_struct *p);
2047 extern int task_nice(const struct task_struct *p);
2048 extern int can_nice(const struct task_struct *p, const int nice);
2049 extern int task_curr(const struct task_struct *p);
2050 extern int idle_cpu(int cpu);
2051 extern int sched_setscheduler(struct task_struct *, int,
2052                               const struct sched_param *);
2053 extern int sched_setscheduler_nocheck(struct task_struct *, int,
2054                                       const struct sched_param *);
2055 extern struct task_struct *idle_task(int cpu);
2056 extern struct task_struct *curr_task(int cpu);
2057 extern void set_curr_task(int cpu, struct task_struct *p);
2058 
2059 void yield(void);
2060 
2061 /*
2062  * The default (Linux) execution domain.
2063  */
2064 extern struct exec_domain       default_exec_domain;
2065 
2066 union thread_union {
2067         struct thread_info thread_info;
2068         unsigned long stack[THREAD_SIZE/sizeof(long)];
2069 };
2070 
2071 #ifndef __HAVE_ARCH_KSTACK_END
2072 static inline int kstack_end(void *addr)
2073 {
2074         /* Reliable end of stack detection:
2075          * Some APM bios versions misalign the stack
2076          */
2077         return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2078 }
2079 #endif
2080 
2081 extern union thread_union init_thread_union;
2082 extern struct task_struct init_task;
2083 
2084 extern struct   mm_struct init_mm;
2085 
2086 extern struct pid_namespace init_pid_ns;
2087 
2088 /*
2089  * find a task by one of its numerical ids
2090  *
2091  * find_task_by_pid_ns():
2092  *      finds a task by its pid in the specified namespace
2093  * find_task_by_vpid():
2094  *      finds a task by its virtual pid
2095  *
2096  * see also find_vpid() etc in include/linux/pid.h
2097  */
2098 
2099 extern struct task_struct *find_task_by_vpid(pid_t nr);
2100 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2101                 struct pid_namespace *ns);
2102 
2103 extern void __set_special_pids(struct pid *pid);
2104 
2105 /* per-UID process charging. */
2106 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
2107 static inline struct user_struct *get_uid(struct user_struct *u)
2108 {
2109         atomic_inc(&u->__count);
2110         return u;
2111 }
2112 extern void free_uid(struct user_struct *);
2113 extern void release_uids(struct user_namespace *ns);
2114 
2115 #include <asm/current.h>
2116 
2117 extern void xtime_update(unsigned long ticks);
2118 
2119 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2120 extern int wake_up_process(struct task_struct *tsk);
2121 extern void wake_up_new_task(struct task_struct *tsk);
2122 #ifdef CONFIG_SMP
2123  extern void kick_process(struct task_struct *tsk);
2124 #else
2125  static inline void kick_process(struct task_struct *tsk) { }
2126 #endif
2127 extern void sched_fork(struct task_struct *p);
2128 extern void sched_dead(struct task_struct *p);
2129 
2130 extern void proc_caches_init(void);
2131 extern void flush_signals(struct task_struct *);
2132 extern void __flush_signals(struct task_struct *);
2133 extern void ignore_signals(struct task_struct *);
2134 extern void flush_signal_handlers(struct task_struct *, int force_default);
2135 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2136 
2137 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2138 {
2139         unsigned long flags;
2140         int ret;
2141 
2142         spin_lock_irqsave(&tsk->sighand->siglock, flags);
2143         ret = dequeue_signal(tsk, mask, info);
2144         spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2145 
2146         return ret;
2147 }       
2148 
2149 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2150                               sigset_t *mask);
2151 extern void unblock_all_signals(void);
2152 extern void release_task(struct task_struct * p);
2153 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2154 extern int force_sigsegv(int, struct task_struct *);
2155 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2156 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2157 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2158 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2159 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2160 extern int kill_pid(struct pid *pid, int sig, int priv);
2161 extern int kill_proc_info(int, struct siginfo *, pid_t);
2162 extern int do_notify_parent(struct task_struct *, int);
2163 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2164 extern void force_sig(int, struct task_struct *);
2165 extern int send_sig(int, struct task_struct *, int);
2166 extern int zap_other_threads(struct task_struct *p);
2167 extern struct sigqueue *sigqueue_alloc(void);
2168 extern void sigqueue_free(struct sigqueue *);
2169 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2170 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2171 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2172 
2173 static inline int kill_cad_pid(int sig, int priv)
2174 {
2175         return kill_pid(cad_pid, sig, priv);
2176 }
2177 
2178 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2179 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2180 #define SEND_SIG_PRIV   ((struct siginfo *) 1)
2181 #define SEND_SIG_FORCED ((struct siginfo *) 2)
2182 
2183 /*
2184  * True if we are on the alternate signal stack.
2185  */
2186 static inline int on_sig_stack(unsigned long sp)
2187 {
2188 #ifdef CONFIG_STACK_GROWSUP
2189         return sp >= current->sas_ss_sp &&
2190                 sp - current->sas_ss_sp < current->sas_ss_size;
2191 #else
2192         return sp > current->sas_ss_sp &&
2193                 sp - current->sas_ss_sp <= current->sas_ss_size;
2194 #endif
2195 }
2196 
2197 static inline int sas_ss_flags(unsigned long sp)
2198 {
2199         return (current->sas_ss_size == 0 ? SS_DISABLE
2200                 : on_sig_stack(sp) ? SS_ONSTACK : 0);
2201 }
2202 
2203 /*
2204  * Routines for handling mm_structs
2205  */
2206 extern struct mm_struct * mm_alloc(void);
2207 
2208 /* mmdrop drops the mm and the page tables */
2209 extern void __mmdrop(struct mm_struct *);
2210 static inline void mmdrop(struct mm_struct * mm)
2211 {
2212         if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2213                 __mmdrop(mm);
2214 }
2215 
2216 /* mmput gets rid of the mappings and all user-space */
2217 extern void mmput(struct mm_struct *);
2218 /* Grab a reference to a task's mm, if it is not already going away */
2219 extern struct mm_struct *get_task_mm(struct task_struct *task);
2220 /* Remove the current tasks stale references to the old mm_struct */
2221 extern void mm_release(struct task_struct *, struct mm_struct *);
2222 /* Allocate a new mm structure and copy contents from tsk->mm */
2223 extern struct mm_struct *dup_mm(struct task_struct *tsk);
2224 
2225 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2226                         struct task_struct *, struct pt_regs *);
2227 extern void flush_thread(void);
2228 extern void exit_thread(void);
2229 
2230 extern void exit_files(struct task_struct *);
2231 extern void __cleanup_sighand(struct sighand_struct *);
2232 
2233 extern void exit_itimers(struct signal_struct *);
2234 extern void flush_itimer_signals(void);
2235 
2236 extern NORET_TYPE void do_group_exit(int);
2237 
2238 extern void daemonize(const char *, ...);
2239 extern int allow_signal(int);
2240 extern int disallow_signal(int);
2241 
2242 extern int do_execve(const char *,
2243                      const char __user * const __user *,
2244                      const char __user * const __user *, struct pt_regs *);
2245 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2246 struct task_struct *fork_idle(int);
2247 
2248 extern void set_task_comm(struct task_struct *tsk, char *from);
2249 extern char *get_task_comm(char *to, struct task_struct *tsk);
2250 
2251 #ifdef CONFIG_SMP
2252 void scheduler_ipi(void);
2253 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2254 #else
2255 static inline void scheduler_ipi(void) { }
2256 static inline unsigned long wait_task_inactive(struct task_struct *p,
2257                                                long match_state)
2258 {
2259         return 1;
2260 }
2261 #endif
2262 
2263 #define next_task(p) \
2264         list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2265 
2266 #define for_each_process(p) \
2267         for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2268 
2269 extern bool current_is_single_threaded(void);
2270 
2271 /*
2272  * Careful: do_each_thread/while_each_thread is a double loop so
2273  *          'break' will not work as expected - use goto instead.
2274  */
2275 #define do_each_thread(g, t) \
2276         for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2277 
2278 #define while_each_thread(g, t) \
2279         while ((t = next_thread(t)) != g)
2280 
2281 static inline int get_nr_threads(struct task_struct *tsk)
2282 {
2283         return tsk->signal->nr_threads;
2284 }
2285 
2286 /* de_thread depends on thread_group_leader not being a pid based check */
2287 #define thread_group_leader(p)  (p == p->group_leader)
2288 
2289 /* Do to the insanities of de_thread it is possible for a process
2290  * to have the pid of the thread group leader without actually being
2291  * the thread group leader.  For iteration through the pids in proc
2292  * all we care about is that we have a task with the appropriate
2293  * pid, we don't actually care if we have the right task.
2294  */
2295 static inline int has_group_leader_pid(struct task_struct *p)
2296 {
2297         return p->pid == p->tgid;
2298 }
2299 
2300 static inline
2301 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2302 {
2303         return p1->tgid == p2->tgid;
2304 }
2305 
2306 static inline struct task_struct *next_thread(const struct task_struct *p)
2307 {
2308         return list_entry_rcu(p->thread_group.next,
2309                               struct task_struct, thread_group);
2310 }
2311 
2312 static inline int thread_group_empty(struct task_struct *p)
2313 {
2314         return list_empty(&p->thread_group);
2315 }
2316 
2317 #define delay_group_leader(p) \
2318                 (thread_group_leader(p) && !thread_group_empty(p))
2319 
2320 static inline int task_detached(struct task_struct *p)
2321 {
2322         return p->exit_signal == -1;
2323 }
2324 
2325 /*
2326  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2327  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2328  * pins the final release of task.io_context.  Also protects ->cpuset and
2329  * ->cgroup.subsys[].
2330  *
2331  * Nests both inside and outside of read_lock(&tasklist_lock).
2332  * It must not be nested with write_lock_irq(&tasklist_lock),
2333  * neither inside nor outside.
2334  */
2335 static inline void task_lock(struct task_struct *p)
2336 {
2337         spin_lock(&p->alloc_lock);
2338 }
2339 
2340 static inline void task_unlock(struct task_struct *p)
2341 {
2342         spin_unlock(&p->alloc_lock);
2343 }
2344 
2345 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2346                                                         unsigned long *flags);
2347 
2348 #define lock_task_sighand(tsk, flags)                                   \
2349 ({      struct sighand_struct *__ss;                                    \
2350         __cond_lock(&(tsk)->sighand->siglock,                           \
2351                     (__ss = __lock_task_sighand(tsk, flags)));          \
2352         __ss;                                                           \
2353 })                                                                      \
2354 
2355 static inline void unlock_task_sighand(struct task_struct *tsk,
2356                                                 unsigned long *flags)
2357 {
2358         spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2359 }
2360 
2361 /* See the declaration of threadgroup_fork_lock in signal_struct. */
2362 #ifdef CONFIG_CGROUPS
2363 static inline void threadgroup_fork_read_lock(struct task_struct *tsk)
2364 {
2365         down_read(&tsk->signal->threadgroup_fork_lock);
2366 }
2367 static inline void threadgroup_fork_read_unlock(struct task_struct *tsk)
2368 {
2369         up_read(&tsk->signal->threadgroup_fork_lock);
2370 }
2371 static inline void threadgroup_fork_write_lock(struct task_struct *tsk)
2372 {
2373         down_write(&tsk->signal->threadgroup_fork_lock);
2374 }
2375 static inline void threadgroup_fork_write_unlock(struct task_struct *tsk)
2376 {
2377         up_write(&tsk->signal->threadgroup_fork_lock);
2378 }
2379 #else
2380 static inline void threadgroup_fork_read_lock(struct task_struct *tsk) {}
2381 static inline void threadgroup_fork_read_unlock(struct task_struct *tsk) {}
2382 static inline void threadgroup_fork_write_lock(struct task_struct *tsk) {}
2383 static inline void threadgroup_fork_write_unlock(struct task_struct *tsk) {}
2384 #endif
2385 
2386 #ifndef __HAVE_THREAD_FUNCTIONS
2387 
2388 #define task_thread_info(task)  ((struct thread_info *)(task)->stack)
2389 #define task_stack_page(task)   ((task)->stack)
2390 
2391 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2392 {
2393         *task_thread_info(p) = *task_thread_info(org);
2394         task_thread_info(p)->task = p;
2395 }
2396 
2397 static inline unsigned long *end_of_stack(struct task_struct *p)
2398 {
2399         return (unsigned long *)(task_thread_info(p) + 1);
2400 }
2401 
2402 #endif
2403 
2404 static inline int object_is_on_stack(void *obj)
2405 {
2406         void *stack = task_stack_page(current);
2407 
2408         return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2409 }
2410 
2411 extern void thread_info_cache_init(void);
2412 
2413 #ifdef CONFIG_DEBUG_STACK_USAGE
2414 static inline unsigned long stack_not_used(struct task_struct *p)
2415 {
2416         unsigned long *n = end_of_stack(p);
2417 
2418         do {    /* Skip over canary */
2419                 n++;
2420         } while (!*n);
2421 
2422         return (unsigned long)n - (unsigned long)end_of_stack(p);
2423 }
2424 #endif
2425 
2426 /* set thread flags in other task's structures
2427  * - see asm/thread_info.h for TIF_xxxx flags available
2428  */
2429 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2430 {
2431         set_ti_thread_flag(task_thread_info(tsk), flag);
2432 }
2433 
2434 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2435 {
2436         clear_ti_thread_flag(task_thread_info(tsk), flag);
2437 }
2438 
2439 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2440 {
2441         return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2442 }
2443 
2444 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2445 {
2446         return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2447 }
2448 
2449 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2450 {
2451         return test_ti_thread_flag(task_thread_info(tsk), flag);
2452 }
2453 
2454 static inline void set_tsk_need_resched(struct task_struct *tsk)
2455 {
2456         set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2457 }
2458 
2459 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2460 {
2461         clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2462 }
2463 
2464 static inline int test_tsk_need_resched(struct task_struct *tsk)
2465 {
2466         return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2467 }
2468 
2469 static inline int restart_syscall(void)
2470 {
2471         set_tsk_thread_flag(current, TIF_SIGPENDING);
2472         return -ERESTARTNOINTR;
2473 }
2474 
2475 static inline int signal_pending(struct task_struct *p)
2476 {
2477         return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2478 }
2479 
2480 static inline int __fatal_signal_pending(struct task_struct *p)
2481 {
2482         return unlikely(sigismember(&p->pending.signal, SIGKILL));
2483 }
2484 
2485 static inline int fatal_signal_pending(struct task_struct *p)
2486 {
2487         return signal_pending(p) && __fatal_signal_pending(p);
2488 }
2489 
2490 static inline int signal_pending_state(long state, struct task_struct *p)
2491 {
2492         if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2493                 return 0;
2494         if (!signal_pending(p))
2495                 return 0;
2496 
2497         return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2498 }
2499 
2500 static inline int need_resched(void)
2501 {
2502         return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2503 }
2504 
2505 /*
2506  * cond_resched() and cond_resched_lock(): latency reduction via
2507  * explicit rescheduling in places that are safe. The return
2508  * value indicates whether a reschedule was done in fact.
2509  * cond_resched_lock() will drop the spinlock before scheduling,
2510  * cond_resched_softirq() will enable bhs before scheduling.
2511  */
2512 extern int _cond_resched(void);
2513 
2514 #define cond_resched() ({                       \
2515         __might_sleep(__FILE__, __LINE__, 0);   \
2516         _cond_resched();                        \
2517 })
2518 
2519 extern int __cond_resched_lock(spinlock_t *lock);
2520 
2521 #ifdef CONFIG_PREEMPT
2522 #define PREEMPT_LOCK_OFFSET     PREEMPT_OFFSET
2523 #else
2524 #define PREEMPT_LOCK_OFFSET     0
2525 #endif
2526 
2527 #define cond_resched_lock(lock) ({                              \
2528         __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2529         __cond_resched_lock(lock);                              \
2530 })
2531 
2532 extern int __cond_resched_softirq(void);
2533 
2534 #define cond_resched_softirq() ({                                       \
2535         __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);      \
2536         __cond_resched_softirq();                                       \
2537 })
2538 
2539 /*
2540  * Does a critical section need to be broken due to another
2541  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2542  * but a general need for low latency)
2543  */
2544 static inline int spin_needbreak(spinlock_t *lock)
2545 {
2546 #ifdef CONFIG_PREEMPT
2547         return spin_is_contended(lock);
2548 #else
2549         return 0;
2550 #endif
2551 }
2552 
2553 /*
2554  * Thread group CPU time accounting.
2555  */
2556 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2557 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2558 
2559 static inline void thread_group_cputime_init(struct signal_struct *sig)
2560 {
2561         spin_lock_init(&sig->cputimer.lock);
2562 }
2563 
2564 /*
2565  * Reevaluate whether the task has signals pending delivery.
2566  * Wake the task if so.
2567  * This is required every time the blocked sigset_t changes.
2568  * callers must hold sighand->siglock.
2569  */
2570 extern void recalc_sigpending_and_wake(struct task_struct *t);
2571 extern void recalc_sigpending(void);
2572 
2573 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
2574 
2575 static inline void signal_wake_up(struct task_struct *t, bool resume)
2576 {
2577         signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
2578 }
2579 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
2580 {
2581         signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
2582 }
2583 
2584 /*
2585  * Wrappers for p->thread_info->cpu access. No-op on UP.
2586  */
2587 #ifdef CONFIG_SMP
2588 
2589 static inline unsigned int task_cpu(const struct task_struct *p)
2590 {
2591         return task_thread_info(p)->cpu;
2592 }
2593 
2594 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2595 
2596 #else
2597 
2598 static inline unsigned int task_cpu(const struct task_struct *p)
2599 {
2600         return 0;
2601 }
2602 
2603 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2604 {
2605 }
2606 
2607 #endif /* CONFIG_SMP */
2608 
2609 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2610 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2611 
2612 extern void normalize_rt_tasks(void);
2613 
2614 #ifdef CONFIG_CGROUP_SCHED
2615 
2616 extern struct task_group root_task_group;
2617 
2618 extern struct task_group *sched_create_group(struct task_group *parent);
2619 extern void sched_destroy_group(struct task_group *tg);
2620 extern void sched_move_task(struct task_struct *tsk);
2621 #ifdef CONFIG_FAIR_GROUP_SCHED
2622 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2623 extern unsigned long sched_group_shares(struct task_group *tg);
2624 #endif
2625 #ifdef CONFIG_RT_GROUP_SCHED
2626 extern int sched_group_set_rt_runtime(struct task_group *tg,
2627                                       long rt_runtime_us);
2628 extern long sched_group_rt_runtime(struct task_group *tg);
2629 extern int sched_group_set_rt_period(struct task_group *tg,
2630                                       long rt_period_us);
2631 extern long sched_group_rt_period(struct task_group *tg);
2632 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2633 #endif
2634 #endif /* CONFIG_CGROUP_SCHED */
2635 
2636 extern int task_can_switch_user(struct user_struct *up,
2637                                         struct task_struct *tsk);
2638 
2639 #ifdef CONFIG_TASK_XACCT
2640 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2641 {
2642         tsk->ioac.rchar += amt;
2643 }
2644 
2645 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2646 {
2647         tsk->ioac.wchar += amt;
2648 }
2649 
2650 static inline void inc_syscr(struct task_struct *tsk)
2651 {
2652         tsk->ioac.syscr++;
2653 }
2654 
2655 static inline void inc_syscw(struct task_struct *tsk)
2656 {
2657         tsk->ioac.syscw++;
2658 }
2659 #else
2660 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2661 {
2662 }
2663 
2664 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2665 {
2666 }
2667 
2668 static inline void inc_syscr(struct task_struct *tsk)
2669 {
2670 }
2671 
2672 static inline void inc_syscw(struct task_struct *tsk)
2673 {
2674 }
2675 #endif
2676 
2677 #ifndef TASK_SIZE_OF
2678 #define TASK_SIZE_OF(tsk)       TASK_SIZE
2679 #endif
2680 
2681 #ifdef CONFIG_MM_OWNER
2682 extern void mm_update_next_owner(struct mm_struct *mm);
2683 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2684 #else
2685 static inline void mm_update_next_owner(struct mm_struct *mm)
2686 {
2687 }
2688 
2689 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2690 {
2691 }
2692 #endif /* CONFIG_MM_OWNER */
2693 
2694 static inline unsigned long task_rlimit(const struct task_struct *tsk,
2695                 unsigned int limit)
2696 {
2697         return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2698 }
2699 
2700 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2701                 unsigned int limit)
2702 {
2703         return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2704 }
2705 
2706 static inline unsigned long rlimit(unsigned int limit)
2707 {
2708         return task_rlimit(current, limit);
2709 }
2710 
2711 static inline unsigned long rlimit_max(unsigned int limit)
2712 {
2713         return task_rlimit_max(current, limit);
2714 }
2715 
2716 #endif /* __KERNEL__ */
2717 
2718 #endif
2719 

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

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

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

osdn.jp