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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
David Woodhouseb7b3c762006-04-27 00:12:56 +01004#include <linux/auxvec.h> /* For AT_VECTOR_SIZE */
5
6/*
7 * cloning flags:
8 */
9#define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
10#define CLONE_VM 0x00000100 /* set if VM shared between processes */
11#define CLONE_FS 0x00000200 /* set if fs info shared between processes */
12#define CLONE_FILES 0x00000400 /* set if open files shared between processes */
13#define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
14#define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
15#define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
16#define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
17#define CLONE_THREAD 0x00010000 /* Same thread group? */
18#define CLONE_NEWNS 0x00020000 /* New namespace group? */
19#define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
20#define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
21#define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */
22#define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */
23#define CLONE_DETACHED 0x00400000 /* Unused, ignored */
24#define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
25#define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */
26#define CLONE_STOPPED 0x02000000 /* Start in stopped state */
Serge E. Hallyn071df102006-10-02 02:18:17 -070027#define CLONE_NEWUTS 0x04000000 /* New utsname group? */
Kirill Korotaev25b21cb2006-10-02 02:18:19 -070028#define CLONE_NEWIPC 0x08000000 /* New ipcs */
Serge E. Hallyn77ec7392007-07-15 23:41:01 -070029#define CLONE_NEWUSER 0x10000000 /* New user namespace */
Eric W. Biederman169e3672007-09-27 17:10:06 -070030#define CLONE_NEWNET 0x40000000 /* New network namespace */
David Woodhouseb7b3c762006-04-27 00:12:56 +010031
32/*
33 * Scheduling policies
34 */
35#define SCHED_NORMAL 0
36#define SCHED_FIFO 1
37#define SCHED_RR 2
38#define SCHED_BATCH 3
Ingo Molnar0e6aca42007-07-09 18:51:57 +020039/* SCHED_ISO: reserved but not implemented yet */
40#define SCHED_IDLE 5
David Woodhouseb7b3c762006-04-27 00:12:56 +010041
David Woodhousea3b67142006-04-25 14:54:40 +010042#ifdef __KERNEL__
David Woodhouseb7b3c762006-04-27 00:12:56 +010043
44struct sched_param {
45 int sched_priority;
46};
47
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#include <asm/param.h> /* for HZ */
49
Linus Torvalds1da177e2005-04-16 15:20:36 -070050#include <linux/capability.h>
51#include <linux/threads.h>
52#include <linux/kernel.h>
53#include <linux/types.h>
54#include <linux/timex.h>
55#include <linux/jiffies.h>
56#include <linux/rbtree.h>
57#include <linux/thread_info.h>
58#include <linux/cpumask.h>
59#include <linux/errno.h>
60#include <linux/nodemask.h>
61
62#include <asm/system.h>
63#include <asm/semaphore.h>
64#include <asm/page.h>
65#include <asm/ptrace.h>
66#include <asm/mmu.h>
67#include <asm/cputime.h>
68
69#include <linux/smp.h>
70#include <linux/sem.h>
71#include <linux/signal.h>
72#include <linux/securebits.h>
73#include <linux/fs_struct.h>
74#include <linux/compiler.h>
75#include <linux/completion.h>
76#include <linux/pid.h>
77#include <linux/percpu.h>
78#include <linux/topology.h>
79#include <linux/seccomp.h>
Ingo Molnare56d0902006-01-08 01:01:37 -080080#include <linux/rcupdate.h>
Ingo Molnar0771dfe2006-03-27 01:16:22 -080081#include <linux/futex.h>
Ingo Molnar23f78d4a2006-06-27 02:54:53 -070082#include <linux/rtmutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
David Woodhousea3b67142006-04-25 14:54:40 +010084#include <linux/time.h>
85#include <linux/param.h>
86#include <linux/resource.h>
87#include <linux/timer.h>
88#include <linux/hrtimer.h>
Andrew Morton7c3ab732006-12-10 02:19:19 -080089#include <linux/task_io_accounting.h>
Dhaval Giani5cb350b2007-10-15 17:00:14 +020090#include <linux/kobject.h>
David Woodhousea3b67142006-04-25 14:54:40 +010091
92#include <asm/processor.h>
H. J. Lu36d57ac2005-09-06 15:16:49 -070093
Linus Torvalds1da177e2005-04-16 15:20:36 -070094struct exec_domain;
Ingo Molnarc87e2832006-06-27 02:54:58 -070095struct futex_pi_state;
Neil Brownd89d8792007-05-01 09:53:42 +020096struct bio;
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
98/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 * List of flags we want to share for kernel threads,
100 * if only because they are not used by them anyway.
101 */
102#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
103
104/*
105 * These are the constant used to fake the fixed-point load-average
106 * counting. Some notes:
107 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
108 * a load-average precision of 10 bits integer + 11 bits fractional
109 * - if you want to count load-averages more often, you need more
110 * precision, or rounding will get you. With 2-second counting freq,
111 * the EXP_n values would be 1981, 2034 and 2043 if still using only
112 * 11 bit fractions.
113 */
114extern unsigned long avenrun[]; /* Load averages */
115
116#define FSHIFT 11 /* nr of bits of precision */
117#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
Linus Torvalds0c2043a2007-10-07 16:17:38 -0700118#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
120#define EXP_5 2014 /* 1/exp(5sec/5min) */
121#define EXP_15 2037 /* 1/exp(5sec/15min) */
122
123#define CALC_LOAD(load,exp,n) \
124 load *= exp; \
125 load += n*(FIXED_1-exp); \
126 load >>= FSHIFT;
127
128extern unsigned long total_forks;
129extern int nr_threads;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130DECLARE_PER_CPU(unsigned long, process_counts);
131extern int nr_processes(void);
132extern unsigned long nr_running(void);
133extern unsigned long nr_uninterruptible(void);
Jack Steinerdb1b1fe2006-03-31 02:31:21 -0800134extern unsigned long nr_active(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135extern unsigned long nr_iowait(void);
Peter Williams2dd73a42006-06-27 02:54:34 -0700136extern unsigned long weighted_cpuload(const int cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137
Ingo Molnar43ae34c2007-07-09 18:52:00 +0200138struct seq_file;
139struct cfs_rq;
Ingo Molnar4cf86d72007-10-15 17:00:14 +0200140struct task_group;
Ingo Molnar43ae34c2007-07-09 18:52:00 +0200141#ifdef CONFIG_SCHED_DEBUG
142extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
143extern void proc_sched_set_task(struct task_struct *p);
144extern void
Ingo Molnar5cef9ec2007-08-09 11:16:47 +0200145print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
Ingo Molnar43ae34c2007-07-09 18:52:00 +0200146#else
147static inline void
148proc_sched_show_task(struct task_struct *p, struct seq_file *m)
149{
150}
151static inline void proc_sched_set_task(struct task_struct *p)
152{
153}
154static inline void
Ingo Molnar5cef9ec2007-08-09 11:16:47 +0200155print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
Ingo Molnar43ae34c2007-07-09 18:52:00 +0200156{
157}
158#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700160/*
161 * Task state bitmask. NOTE! These bits are also
162 * encoded in fs/proc/array.c: get_task_state().
163 *
164 * We have two separate sets of flags: task->state
165 * is about runnability, while task->exit_state are
166 * about the task exiting. Confusing, but this way
167 * modifying one set can't modify the other one by
168 * mistake.
169 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170#define TASK_RUNNING 0
171#define TASK_INTERRUPTIBLE 1
172#define TASK_UNINTERRUPTIBLE 2
Linus Torvalds4a8342d2005-09-29 15:18:21 -0700173#define TASK_STOPPED 4
174#define TASK_TRACED 8
175/* in tsk->exit_state */
176#define EXIT_ZOMBIE 16
177#define EXIT_DEAD 32
178/* in tsk->state again */
Mike Galbraithaf927232007-10-15 17:00:13 +0200179#define TASK_DEAD 64
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180
181#define __set_task_state(tsk, state_value) \
182 do { (tsk)->state = (state_value); } while (0)
183#define set_task_state(tsk, state_value) \
184 set_mb((tsk)->state, (state_value))
185
Andrew Morton498d0c52005-09-13 01:25:14 -0700186/*
187 * set_current_state() includes a barrier so that the write of current->state
188 * is correctly serialised wrt the caller's subsequent test of whether to
189 * actually sleep:
190 *
191 * set_current_state(TASK_UNINTERRUPTIBLE);
192 * if (do_i_need_to_sleep())
193 * schedule();
194 *
195 * If the caller does not need such serialisation then use __set_current_state()
196 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197#define __set_current_state(state_value) \
198 do { current->state = (state_value); } while (0)
199#define set_current_state(state_value) \
200 set_mb(current->state, (state_value))
201
202/* Task command name length */
203#define TASK_COMM_LEN 16
204
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205#include <linux/spinlock.h>
206
207/*
208 * This serializes "schedule()" and also protects
209 * the run-queue from deletions/modifications (but
210 * _adding_ to the beginning of the run-queue has
211 * a separate lock).
212 */
213extern rwlock_t tasklist_lock;
214extern spinlock_t mmlist_lock;
215
Ingo Molnar36c8b582006-07-03 00:25:41 -0700216struct task_struct;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217
218extern void sched_init(void);
219extern void sched_init_smp(void);
Ingo Molnar36c8b582006-07-03 00:25:41 -0700220extern void init_idle(struct task_struct *idle, int cpu);
Ingo Molnar1df21052007-07-09 18:51:58 +0200221extern void init_idle_bootup_task(struct task_struct *idle);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
223extern cpumask_t nohz_cpu_mask;
Siddha, Suresh B46cb4b72007-05-08 00:32:51 -0700224#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
225extern int select_nohz_load_balancer(int cpu);
226#else
227static inline int select_nohz_load_balancer(int cpu)
228{
229 return 0;
230}
231#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232
Ingo Molnare59e2ae2006-12-06 20:35:59 -0800233/*
Ingo Molnar39bc89f2007-04-25 20:50:03 -0700234 * Only dump TASK_* tasks. (0 for all tasks)
Ingo Molnare59e2ae2006-12-06 20:35:59 -0800235 */
236extern void show_state_filter(unsigned long state_filter);
237
238static inline void show_state(void)
239{
Ingo Molnar39bc89f2007-04-25 20:50:03 -0700240 show_state_filter(0);
Ingo Molnare59e2ae2006-12-06 20:35:59 -0800241}
242
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243extern void show_regs(struct pt_regs *);
244
245/*
246 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
247 * task), SP is the stack pointer of the first frame that should be shown in the back
248 * trace (or NULL if the entire call-chain of the task should be shown).
249 */
250extern void show_stack(struct task_struct *task, unsigned long *sp);
251
252void io_schedule(void);
253long io_schedule_timeout(long timeout);
254
255extern void cpu_init (void);
256extern void trap_init(void);
257extern void update_process_times(int user);
258extern void scheduler_tick(void);
259
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700260#ifdef CONFIG_DETECT_SOFTLOCKUP
Ingo Molnar6687a972006-03-24 03:18:41 -0800261extern void softlockup_tick(void);
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700262extern void spawn_softlockup_task(void);
263extern void touch_softlockup_watchdog(void);
Jeremy Fitzhardinge04c91672007-05-08 00:28:05 -0700264extern void touch_all_softlockup_watchdogs(void);
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700265#else
Ingo Molnar6687a972006-03-24 03:18:41 -0800266static inline void softlockup_tick(void)
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700267{
268}
269static inline void spawn_softlockup_task(void)
270{
271}
272static inline void touch_softlockup_watchdog(void)
273{
274}
Jeremy Fitzhardinge04c91672007-05-08 00:28:05 -0700275static inline void touch_all_softlockup_watchdogs(void)
276{
277}
Ingo Molnar8446f1d2005-09-06 15:16:27 -0700278#endif
279
280
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281/* Attach to any functions which should be ignored in wchan output. */
282#define __sched __attribute__((__section__(".sched.text")))
283/* Is this address in the __sched functions? */
284extern int in_sched_functions(unsigned long addr);
285
286#define MAX_SCHEDULE_TIMEOUT LONG_MAX
287extern signed long FASTCALL(schedule_timeout(signed long timeout));
Nishanth Aravamudan64ed93a2005-09-10 00:27:21 -0700288extern signed long schedule_timeout_interruptible(signed long timeout);
289extern signed long schedule_timeout_uninterruptible(signed long timeout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290asmlinkage void schedule(void);
291
Serge E. Hallynab516012006-10-02 02:18:06 -0700292struct nsproxy;
Cedric Le Goateracce2922007-07-15 23:40:59 -0700293struct user_namespace;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294
295/* Maximum number of active map areas.. This is a random (large) number */
296#define DEFAULT_MAX_MAP_COUNT 65536
297
298extern int sysctl_max_map_count;
299
300#include <linux/aio.h>
301
302extern unsigned long
303arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
304 unsigned long, unsigned long);
305extern unsigned long
306arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
307 unsigned long len, unsigned long pgoff,
308 unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700309extern void arch_unmap_area(struct mm_struct *, unsigned long);
310extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700312#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
313/*
314 * The mm counters are not protected by its page_table_lock,
315 * so must be incremented atomically.
316 */
Christoph Lameterd3cb4872006-01-06 00:11:20 -0800317#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
318#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
319#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
320#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
321#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
322typedef atomic_long_t mm_counter_t;
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700323
324#else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
325/*
326 * The mm counters are protected by its page_table_lock,
327 * so can be incremented directly.
328 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
330#define get_mm_counter(mm, member) ((mm)->_##member)
331#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
332#define inc_mm_counter(mm, member) (mm)->_##member++
333#define dec_mm_counter(mm, member) (mm)->_##member--
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700334typedef unsigned long mm_counter_t;
Hugh Dickins42946212005-10-29 18:16:05 -0700335
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700336#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
337
338#define get_mm_rss(mm) \
339 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
Hugh Dickins365e9c872005-10-29 18:16:18 -0700340#define update_hiwater_rss(mm) do { \
341 unsigned long _rss = get_mm_rss(mm); \
342 if ((mm)->hiwater_rss < _rss) \
343 (mm)->hiwater_rss = _rss; \
344} while (0)
345#define update_hiwater_vm(mm) do { \
346 if ((mm)->hiwater_vm < (mm)->total_vm) \
347 (mm)->hiwater_vm = (mm)->total_vm; \
348} while (0)
349
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -0700350extern void set_dumpable(struct mm_struct *mm, int value);
351extern int get_dumpable(struct mm_struct *mm);
352
353/* mm flags */
Kawai, Hidehiro3cb4a0b2007-07-19 01:48:28 -0700354/* dumpable bits */
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -0700355#define MMF_DUMPABLE 0 /* core dump is permitted */
356#define MMF_DUMP_SECURELY 1 /* core file is readable only by root */
Kawai, Hidehiro3cb4a0b2007-07-19 01:48:28 -0700357#define MMF_DUMPABLE_BITS 2
358
359/* coredump filter bits */
360#define MMF_DUMP_ANON_PRIVATE 2
361#define MMF_DUMP_ANON_SHARED 3
362#define MMF_DUMP_MAPPED_PRIVATE 4
363#define MMF_DUMP_MAPPED_SHARED 5
364#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
365#define MMF_DUMP_FILTER_BITS 4
366#define MMF_DUMP_FILTER_MASK \
367 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
368#define MMF_DUMP_FILTER_DEFAULT \
369 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED))
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -0700370
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371struct mm_struct {
372 struct vm_area_struct * mmap; /* list of VMAs */
373 struct rb_root mm_rb;
374 struct vm_area_struct * mmap_cache; /* last find_vma result */
375 unsigned long (*get_unmapped_area) (struct file *filp,
376 unsigned long addr, unsigned long len,
377 unsigned long pgoff, unsigned long flags);
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700378 void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
Benjamin Herrenschmidt0551fbd2006-02-28 16:59:19 -0800379 unsigned long mmap_base; /* base of mmap area */
380 unsigned long task_size; /* size of task vm space */
381 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
Wolfgang Wander1363c3c2005-06-21 17:14:49 -0700382 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 pgd_t * pgd;
384 atomic_t mm_users; /* How many users with user space? */
385 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
386 int map_count; /* number of VMAs */
387 struct rw_semaphore mmap_sem;
388 spinlock_t page_table_lock; /* Protects page tables and some counters */
389
390 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
391 * together off init_mm.mmlist, and are protected
392 * by mmlist_lock
393 */
394
Hugh Dickinsf412ac02005-10-29 18:16:41 -0700395 /* Special counters, in some configurations protected by the
396 * page_table_lock, in other configurations by being atomic.
397 */
Hugh Dickins42946212005-10-29 18:16:05 -0700398 mm_counter_t _file_rss;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 mm_counter_t _anon_rss;
400
Hugh Dickinsf4499522005-10-29 18:16:19 -0700401 unsigned long hiwater_rss; /* High-watermark of RSS usage */
402 unsigned long hiwater_vm; /* High-water virtual memory usage */
403
404 unsigned long total_vm, locked_vm, shared_vm, exec_vm;
405 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
406 unsigned long start_code, end_code, start_data, end_data;
407 unsigned long start_brk, brk, start_stack;
408 unsigned long arg_start, arg_end, env_start, env_end;
409
H. J. Lu36d57ac2005-09-06 15:16:49 -0700410 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 cpumask_t cpu_vm_mask;
413
414 /* Architecture-specific MM context */
415 mm_context_t context;
416
Ashwin Chaugule7602bdf2006-12-06 20:31:57 -0800417 /* Swap token stuff */
418 /*
419 * Last value of global fault stamp as seen by this process.
420 * In other words, this value gives an indication of how long
421 * it has been since this task got the token.
422 * Look at mm/thrash.c
423 */
424 unsigned int faultstamp;
425 unsigned int token_priority;
426 unsigned int last_interval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427
Kawai, Hidehiro6c5d5232007-07-19 01:48:27 -0700428 unsigned long flags; /* Must use atomic bitops to access the bits */
Arnaldo Carvalho de Melo36de6432006-12-06 20:33:42 -0800429
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 /* coredumping support */
431 int core_waiters;
432 struct completion *core_startup_done, core_done;
433
434 /* aio bits */
435 rwlock_t ioctx_list_lock;
436 struct kioctx *ioctx_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437};
438
439struct sighand_struct {
440 atomic_t count;
441 struct k_sigaction action[_NSIG];
442 spinlock_t siglock;
Davide Libenzib8fceee2007-09-20 12:40:16 -0700443 wait_queue_head_t signalfd_wqh;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444};
445
KaiGai Kohei0e464812006-06-25 05:49:24 -0700446struct pacct_struct {
KaiGai Koheif6ec29a2006-06-25 05:49:25 -0700447 int ac_flag;
448 long ac_exitcode;
KaiGai Kohei0e464812006-06-25 05:49:24 -0700449 unsigned long ac_mem;
KaiGai Kohei77787bf2006-06-25 05:49:26 -0700450 cputime_t ac_utime, ac_stime;
451 unsigned long ac_minflt, ac_majflt;
KaiGai Kohei0e464812006-06-25 05:49:24 -0700452};
453
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454/*
455 * NOTE! "signal_struct" does not have it's own
456 * locking, because a shared signal_struct always
457 * implies a shared sighand_struct, so locking
458 * sighand_struct is always a proper superset of
459 * the locking of signal_struct.
460 */
461struct signal_struct {
462 atomic_t count;
463 atomic_t live;
464
465 wait_queue_head_t wait_chldexit; /* for wait4() */
466
467 /* current thread group signal load-balancing target: */
Ingo Molnar36c8b582006-07-03 00:25:41 -0700468 struct task_struct *curr_target;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469
470 /* shared signal handling: */
471 struct sigpending shared_pending;
472
473 /* thread group exit support */
474 int group_exit_code;
475 /* overloaded:
476 * - notify group_exit_task when ->count is equal to notify_count
477 * - everyone except group_exit_task is stopped during signal delivery
478 * of fatal signals, group_exit_task processes the signal.
479 */
480 struct task_struct *group_exit_task;
481 int notify_count;
482
483 /* thread group stop support, overloads group_exit_code too */
484 int group_stop_count;
485 unsigned int flags; /* see SIGNAL_* flags below */
486
487 /* POSIX.1b Interval Timers */
488 struct list_head posix_timers;
489
490 /* ITIMER_REAL timer for the process */
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800491 struct hrtimer real_timer;
Roman Zippel05cfb612006-03-26 01:38:12 -0800492 struct task_struct *tsk;
Thomas Gleixner2ff678b2006-01-09 20:52:34 -0800493 ktime_t it_real_incr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
495 /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
496 cputime_t it_prof_expires, it_virt_expires;
497 cputime_t it_prof_incr, it_virt_incr;
498
499 /* job control IDs */
500 pid_t pgrp;
Eric W. Biedermanab521dc2007-02-12 00:53:00 -0800501 struct pid *tty_old_pgrp;
Cedric Le Goater1ec320a2006-12-08 02:37:55 -0800502
503 union {
504 pid_t session __deprecated;
505 pid_t __session;
506 };
507
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 /* boolean value for session group leader */
509 int leader;
510
511 struct tty_struct *tty; /* NULL if no tty */
512
513 /*
514 * Cumulative resource counters for dead threads in the group,
515 * and for reaped dead child processes forked by this group.
516 * Live threads maintain their own counters and add to these
517 * in __exit_signal, except for the group leader.
518 */
519 cputime_t utime, stime, cutime, cstime;
Laurent Vivier9ac52312007-10-15 17:00:19 +0200520 cputime_t gtime;
521 cputime_t cgtime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
523 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
Eric Dumazet6eaeeab2007-05-10 22:22:37 -0700524 unsigned long inblock, oublock, cinblock, coublock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525
526 /*
527 * Cumulative ns of scheduled CPU time for dead threads in the
528 * group, not including a zombie group leader. (This only differs
529 * from jiffies_to_ns(utime + stime) if sched_clock uses something
530 * other than jiffies.)
531 */
Ingo Molnar41b86e92007-07-09 18:51:58 +0200532 unsigned long long sum_sched_runtime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533
534 /*
535 * We don't bother to synchronize most readers of this at all,
536 * because there is no reader checking a limit that actually needs
537 * to get both rlim_cur and rlim_max atomically, and either one
538 * alone is a single word that can safely be read normally.
539 * getrlimit/setrlimit use task_lock(current->group_leader) to
540 * protect this instead of the siglock, because they really
541 * have no need to disable irqs.
542 */
543 struct rlimit rlim[RLIM_NLIMITS];
544
545 struct list_head cpu_timers[3];
546
547 /* keep the process-shared keyrings here so that they do the right
548 * thing in threads created with CLONE_THREAD */
549#ifdef CONFIG_KEYS
550 struct key *session_keyring; /* keyring inherited over fork */
551 struct key *process_keyring; /* keyring private to this process */
552#endif
KaiGai Kohei0e464812006-06-25 05:49:24 -0700553#ifdef CONFIG_BSD_PROCESS_ACCT
554 struct pacct_struct pacct; /* per-process accounting information */
555#endif
Shailabh Nagarad4ecbc2006-07-14 00:24:44 -0700556#ifdef CONFIG_TASKSTATS
Shailabh Nagarad4ecbc2006-07-14 00:24:44 -0700557 struct taskstats *stats;
558#endif
Miloslav Trmac522ed772007-07-15 23:40:56 -0700559#ifdef CONFIG_AUDIT
560 unsigned audit_tty;
561 struct tty_audit_buf *tty_audit_buf;
562#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563};
564
Nick Piggin4866cde2005-06-25 14:57:23 -0700565/* Context switch must be unlocked if interrupts are to be enabled */
566#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
567# define __ARCH_WANT_UNLOCKED_CTXSW
568#endif
569
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570/*
571 * Bits in flags field of signal_struct.
572 */
573#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
574#define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
575#define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
576#define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
577
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578/*
579 * Some day this will be a full-fledged user tracking system..
580 */
581struct user_struct {
582 atomic_t __count; /* reference count */
583 atomic_t processes; /* How many processes does this user have? */
584 atomic_t files; /* How many open files does this user have? */
585 atomic_t sigpending; /* How many pending signals does this user have? */
Amy Griffis2d9048e2006-06-01 13:10:59 -0700586#ifdef CONFIG_INOTIFY_USER
Robert Love0eeca282005-07-12 17:06:03 -0400587 atomic_t inotify_watches; /* How many inotify watches does this user have? */
588 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
589#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 /* protected by mq_lock */
591 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
592 unsigned long locked_shm; /* How many pages of mlocked shm ? */
593
594#ifdef CONFIG_KEYS
595 struct key *uid_keyring; /* UID specific keyring */
596 struct key *session_keyring; /* UID's default session keyring */
597#endif
598
599 /* Hash table maintenance information */
Pavel Emelyanov735de222007-09-18 22:46:44 -0700600 struct hlist_node uidhash_node;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 uid_t uid;
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200602
603#ifdef CONFIG_FAIR_USER_SCHED
Ingo Molnar4cf86d72007-10-15 17:00:14 +0200604 struct task_group *tg;
Dhaval Giani5cb350b2007-10-15 17:00:14 +0200605 struct kset kset;
606 struct subsys_attribute user_attr;
607 struct work_struct work;
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200608#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609};
610
Dhaval Giani5cb350b2007-10-15 17:00:14 +0200611#ifdef CONFIG_FAIR_USER_SCHED
612extern int uids_kobject_init(void);
613#else
614static inline int uids_kobject_init(void) { return 0; }
615#endif
616
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617extern struct user_struct *find_user(uid_t);
618
619extern struct user_struct root_user;
620#define INIT_USER (&root_user)
621
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622struct backing_dev_info;
623struct reclaim_state;
624
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700625#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626struct sched_info {
627 /* cumulative counters */
Ingo Molnar2d723762007-10-15 17:00:12 +0200628 unsigned long pcount; /* # of times run on this cpu */
Balbir Singh172ba842007-07-09 18:52:00 +0200629 unsigned long long cpu_time, /* time spent on the cpu */
630 run_delay; /* time spent waiting on a runqueue */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631
632 /* timestamps */
Balbir Singh172ba842007-07-09 18:52:00 +0200633 unsigned long long last_arrival,/* when we last ran on a cpu */
634 last_queued; /* when we were last queued to run */
Ingo Molnarb8efb562007-10-15 17:00:10 +0200635#ifdef CONFIG_SCHEDSTATS
636 /* BKL stats */
Ingo Molnar2d723762007-10-15 17:00:12 +0200637 unsigned long bkl_count;
Ingo Molnarb8efb562007-10-15 17:00:10 +0200638#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639};
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700640#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700642#ifdef CONFIG_SCHEDSTATS
Helge Deller15ad7cd2006-12-06 20:40:36 -0800643extern const struct file_operations proc_schedstat_operations;
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700644#endif /* CONFIG_SCHEDSTATS */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645
Shailabh Nagarca74e922006-07-14 00:24:36 -0700646#ifdef CONFIG_TASK_DELAY_ACCT
647struct task_delay_info {
648 spinlock_t lock;
649 unsigned int flags; /* Private per-task flags */
650
651 /* For each stat XXX, add following, aligned appropriately
652 *
653 * struct timespec XXX_start, XXX_end;
654 * u64 XXX_delay;
655 * u32 XXX_count;
656 *
657 * Atomicity of updates to XXX_delay, XXX_count protected by
658 * single lock above (split into XXX_lock if contention is an issue).
659 */
Shailabh Nagar0ff92242006-07-14 00:24:37 -0700660
661 /*
662 * XXX_count is incremented on every XXX operation, the delay
663 * associated with the operation is added to XXX_delay.
664 * XXX_delay contains the accumulated delay time in nanoseconds.
665 */
666 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
667 u64 blkio_delay; /* wait for sync block io completion */
668 u64 swapin_delay; /* wait for swapin block io completion */
669 u32 blkio_count; /* total count of the number of sync block */
670 /* io operations performed */
671 u32 swapin_count; /* total count of the number of swapin block */
672 /* io operations performed */
Shailabh Nagarca74e922006-07-14 00:24:36 -0700673};
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700674#endif /* CONFIG_TASK_DELAY_ACCT */
675
676static inline int sched_info_on(void)
677{
678#ifdef CONFIG_SCHEDSTATS
679 return 1;
680#elif defined(CONFIG_TASK_DELAY_ACCT)
681 extern int delayacct_on;
682 return delayacct_on;
683#else
684 return 0;
Shailabh Nagarca74e922006-07-14 00:24:36 -0700685#endif
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700686}
Shailabh Nagarca74e922006-07-14 00:24:36 -0700687
Ingo Molnard15bcfd2007-07-09 18:51:57 +0200688enum cpu_idle_type {
689 CPU_IDLE,
690 CPU_NOT_IDLE,
691 CPU_NEWLY_IDLE,
692 CPU_MAX_IDLE_TYPES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693};
694
695/*
696 * sched-domains (multiprocessor balancing) declarations:
697 */
Ingo Molnar9aa7b362007-07-09 18:51:58 +0200698
699/*
700 * Increase resolution of nice-level calculations:
701 */
702#define SCHED_LOAD_SHIFT 10
703#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
704
Suresh Siddhaf8700df2007-08-23 15:18:02 +0200705#define SCHED_LOAD_SCALE_FUZZ SCHED_LOAD_SCALE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706
Peter Williams2dd73a42006-06-27 02:54:34 -0700707#ifdef CONFIG_SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708#define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
709#define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
710#define SD_BALANCE_EXEC 4 /* Balance on exec */
Nick Piggin147cbb42005-06-25 14:57:19 -0700711#define SD_BALANCE_FORK 8 /* Balance on fork, clone */
712#define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
713#define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
714#define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
715#define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700716#define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */
Siddha, Suresh B89c47102006-10-03 01:14:09 -0700717#define SD_SHARE_PKG_RESOURCES 512 /* Domain members share cpu pkg resources */
Christoph Lameter08c183f2006-12-10 02:20:29 -0800718#define SD_SERIALIZE 1024 /* Only a single load balancing instance */
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700719
Siddha, Suresh B89c47102006-10-03 01:14:09 -0700720#define BALANCE_FOR_MC_POWER \
721 (sched_smt_power_savings ? SD_POWERSAVINGS_BALANCE : 0)
722
723#define BALANCE_FOR_PKG_POWER \
724 ((sched_mc_power_savings || sched_smt_power_savings) ? \
725 SD_POWERSAVINGS_BALANCE : 0)
726
727#define test_sd_parent(sd, flag) ((sd->parent && \
728 (sd->parent->flags & flag)) ? 1 : 0)
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -0700729
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730
731struct sched_group {
732 struct sched_group *next; /* Must be a circular list */
733 cpumask_t cpumask;
734
735 /*
736 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
737 * single CPU. This is read only (except for setup, hotplug CPU).
Eric Dumazet5517d862007-05-08 00:32:57 -0700738 * Note : Never change cpu_power without recompute its reciprocal
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 */
Eric Dumazet5517d862007-05-08 00:32:57 -0700740 unsigned int __cpu_power;
741 /*
742 * reciprocal value of cpu_power to avoid expensive divides
743 * (see include/linux/reciprocal_div.h)
744 */
745 u32 reciprocal_cpu_power;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746};
747
748struct sched_domain {
749 /* These fields must be setup */
750 struct sched_domain *parent; /* top domain must be null terminated */
Siddha, Suresh B1a848872006-10-03 01:14:08 -0700751 struct sched_domain *child; /* bottom domain must be null terminated */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 struct sched_group *groups; /* the balancing groups of the domain */
753 cpumask_t span; /* span of all CPUs in this domain */
754 unsigned long min_interval; /* Minimum balance interval ms */
755 unsigned long max_interval; /* Maximum balance interval ms */
756 unsigned int busy_factor; /* less balancing by factor if busy */
757 unsigned int imbalance_pct; /* No balance until over watermark */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
Nick Piggin78979862005-06-25 14:57:13 -0700759 unsigned int busy_idx;
760 unsigned int idle_idx;
761 unsigned int newidle_idx;
762 unsigned int wake_idx;
Nick Piggin147cbb42005-06-25 14:57:19 -0700763 unsigned int forkexec_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764 int flags; /* See SD_* */
765
766 /* Runtime fields. */
767 unsigned long last_balance; /* init to jiffies. units in jiffies */
768 unsigned int balance_interval; /* initialise to 1. units in ms. */
769 unsigned int nr_balance_failed; /* initialise to 0 */
770
771#ifdef CONFIG_SCHEDSTATS
772 /* load_balance() stats */
Ingo Molnar2d723762007-10-15 17:00:12 +0200773 unsigned long lb_count[CPU_MAX_IDLE_TYPES];
Ingo Molnard15bcfd2007-07-09 18:51:57 +0200774 unsigned long lb_failed[CPU_MAX_IDLE_TYPES];
775 unsigned long lb_balanced[CPU_MAX_IDLE_TYPES];
776 unsigned long lb_imbalance[CPU_MAX_IDLE_TYPES];
777 unsigned long lb_gained[CPU_MAX_IDLE_TYPES];
778 unsigned long lb_hot_gained[CPU_MAX_IDLE_TYPES];
779 unsigned long lb_nobusyg[CPU_MAX_IDLE_TYPES];
780 unsigned long lb_nobusyq[CPU_MAX_IDLE_TYPES];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781
782 /* Active load balancing */
Ingo Molnar2d723762007-10-15 17:00:12 +0200783 unsigned long alb_count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 unsigned long alb_failed;
785 unsigned long alb_pushed;
786
Nick Piggin68767a02005-06-25 14:57:20 -0700787 /* SD_BALANCE_EXEC stats */
Ingo Molnar2d723762007-10-15 17:00:12 +0200788 unsigned long sbe_count;
Nick Piggin68767a02005-06-25 14:57:20 -0700789 unsigned long sbe_balanced;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 unsigned long sbe_pushed;
791
Nick Piggin68767a02005-06-25 14:57:20 -0700792 /* SD_BALANCE_FORK stats */
Ingo Molnar2d723762007-10-15 17:00:12 +0200793 unsigned long sbf_count;
Nick Piggin68767a02005-06-25 14:57:20 -0700794 unsigned long sbf_balanced;
795 unsigned long sbf_pushed;
796
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 /* try_to_wake_up() stats */
798 unsigned long ttwu_wake_remote;
799 unsigned long ttwu_move_affine;
800 unsigned long ttwu_move_balance;
801#endif
802};
803
Srivatsa Vaddagiri51888ca2006-06-27 02:54:38 -0700804extern int partition_sched_domains(cpumask_t *partition1,
Dinakar Guniguntala1a20ff22005-06-25 14:57:33 -0700805 cpumask_t *partition2);
akpm@osdl.org198e2f12006-01-12 01:05:30 -0800806
akpm@osdl.org198e2f12006-01-12 01:05:30 -0800807#endif /* CONFIG_SMP */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808
Con Kolivasd02c7a82007-07-26 13:40:43 +0200809/*
810 * A runqueue laden with a single nice 0 task scores a weighted_cpuload of
811 * SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a
812 * task of nice 0 or enough lower priority tasks to bring up the
813 * weighted_cpuload
814 */
815static inline int above_background_load(void)
816{
817 unsigned long cpu;
818
819 for_each_online_cpu(cpu) {
820 if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE)
821 return 1;
822 }
823 return 0;
824}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825
826struct io_context; /* See blkdev.h */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827struct cpuset;
828
829#define NGROUPS_SMALL 32
830#define NGROUPS_PER_BLOCK ((int)(PAGE_SIZE / sizeof(gid_t)))
831struct group_info {
832 int ngroups;
833 atomic_t usage;
834 gid_t small_block[NGROUPS_SMALL];
835 int nblocks;
836 gid_t *blocks[0];
837};
838
839/*
840 * get_group_info() must be called with the owning task locked (via task_lock())
841 * when task != current. The reason being that the vast majority of callers are
842 * looking at current->group_info, which can not be changed except by the
843 * current task. Changing current->group_info requires the task lock, too.
844 */
845#define get_group_info(group_info) do { \
846 atomic_inc(&(group_info)->usage); \
847} while (0)
848
849#define put_group_info(group_info) do { \
850 if (atomic_dec_and_test(&(group_info)->usage)) \
851 groups_free(group_info); \
852} while (0)
853
David Howells3e301482005-06-23 22:00:56 -0700854extern struct group_info *groups_alloc(int gidsetsize);
855extern void groups_free(struct group_info *group_info);
856extern int set_current_groups(struct group_info *group_info);
857extern int groups_search(struct group_info *group_info, gid_t grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858/* access the groups "array" with this macro */
859#define GROUP_AT(gi, i) \
860 ((gi)->blocks[(i)/NGROUPS_PER_BLOCK][(i)%NGROUPS_PER_BLOCK])
861
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700862#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
Ingo Molnar36c8b582006-07-03 00:25:41 -0700863extern void prefetch_stack(struct task_struct *t);
Chen, Kenneth W383f2832005-09-09 13:02:02 -0700864#else
865static inline void prefetch_stack(struct task_struct *t) { }
866#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867
868struct audit_context; /* See audit.c */
869struct mempolicy;
Jens Axboeb92ce552006-04-11 13:52:07 +0200870struct pipe_inode_info;
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700871struct uts_namespace;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872
Ingo Molnar20b8a592007-07-09 18:51:58 +0200873struct rq;
874struct sched_domain;
875
876struct sched_class {
Ingo Molnar5522d5d2007-10-15 17:00:12 +0200877 const struct sched_class *next;
Ingo Molnar20b8a592007-07-09 18:51:58 +0200878
Ingo Molnarfd390f62007-08-09 11:16:48 +0200879 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
Ingo Molnarf02231e2007-08-09 11:16:48 +0200880 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
Dmitry Adamushko4530d7a2007-10-15 17:00:08 +0200881 void (*yield_task) (struct rq *rq);
Ingo Molnar20b8a592007-07-09 18:51:58 +0200882
883 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p);
884
Ingo Molnarfb8d4722007-08-09 11:16:48 +0200885 struct task_struct * (*pick_next_task) (struct rq *rq);
Ingo Molnar31ee5292007-08-09 11:16:49 +0200886 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
Ingo Molnar20b8a592007-07-09 18:51:58 +0200887
Peter Williams43010652007-08-09 11:16:46 +0200888 unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
Ingo Molnar20b8a592007-07-09 18:51:58 +0200889 struct rq *busiest,
890 unsigned long max_nr_move, unsigned long max_load_move,
891 struct sched_domain *sd, enum cpu_idle_type idle,
Peter Williamsa4ac01c2007-08-09 11:16:46 +0200892 int *all_pinned, int *this_best_prio);
Ingo Molnar20b8a592007-07-09 18:51:58 +0200893
Srivatsa Vaddagiri83b699e2007-10-15 17:00:08 +0200894 void (*set_curr_task) (struct rq *rq);
Ingo Molnar20b8a592007-07-09 18:51:58 +0200895 void (*task_tick) (struct rq *rq, struct task_struct *p);
Ingo Molnaree0827d2007-08-09 11:16:49 +0200896 void (*task_new) (struct rq *rq, struct task_struct *p);
Ingo Molnar20b8a592007-07-09 18:51:58 +0200897};
898
899struct load_weight {
900 unsigned long weight, inv_weight;
901};
902
903/*
904 * CFS stats for a schedulable entity (task, task-group etc)
905 *
906 * Current field usage histogram:
907 *
908 * 4 se->block_start
909 * 4 se->run_node
910 * 4 se->sleep_start
Ingo Molnar20b8a592007-07-09 18:51:58 +0200911 * 6 se->load.weight
Ingo Molnar20b8a592007-07-09 18:51:58 +0200912 */
913struct sched_entity {
Ingo Molnar20b8a592007-07-09 18:51:58 +0200914 struct load_weight load; /* for load-balancing */
915 struct rb_node run_node;
916 unsigned int on_rq;
Mike Galbraith95938a32007-10-15 17:00:14 +0200917 int peer_preempt;
Ingo Molnar20b8a592007-07-09 18:51:58 +0200918
Ingo Molnar20b8a592007-07-09 18:51:58 +0200919 u64 exec_start;
Ingo Molnar94c18222007-08-02 17:41:40 +0200920 u64 sum_exec_runtime;
Ingo Molnare9acbff2007-10-15 17:00:04 +0200921 u64 vruntime;
Ingo Molnarf6cf8912007-08-28 12:53:24 +0200922 u64 prev_sum_exec_runtime;
Ingo Molnar94c18222007-08-02 17:41:40 +0200923
924#ifdef CONFIG_SCHEDSTATS
925 u64 wait_start;
926 u64 wait_max;
Ingo Molnar94c18222007-08-02 17:41:40 +0200927
928 u64 sleep_start;
Ingo Molnar20b8a592007-07-09 18:51:58 +0200929 u64 sleep_max;
Ingo Molnar94c18222007-08-02 17:41:40 +0200930 s64 sum_sleep_runtime;
931
932 u64 block_start;
Ingo Molnar20b8a592007-07-09 18:51:58 +0200933 u64 block_max;
934 u64 exec_max;
Ingo Molnareba1ed42007-10-15 17:00:02 +0200935 u64 slice_max;
Ingo Molnarcc367732007-10-15 17:00:18 +0200936
937 u64 nr_migrations;
938 u64 nr_migrations_cold;
939 u64 nr_failed_migrations_affine;
940 u64 nr_failed_migrations_running;
941 u64 nr_failed_migrations_hot;
942 u64 nr_forced_migrations;
943 u64 nr_forced2_migrations;
944
945 u64 nr_wakeups;
946 u64 nr_wakeups_sync;
947 u64 nr_wakeups_migrate;
948 u64 nr_wakeups_local;
949 u64 nr_wakeups_remote;
950 u64 nr_wakeups_affine;
951 u64 nr_wakeups_affine_attempts;
952 u64 nr_wakeups_passive;
953 u64 nr_wakeups_idle;
Ingo Molnar94c18222007-08-02 17:41:40 +0200954#endif
955
Ingo Molnar20b8a592007-07-09 18:51:58 +0200956#ifdef CONFIG_FAIR_GROUP_SCHED
957 struct sched_entity *parent;
958 /* rq on which this entity is (to be) queued: */
959 struct cfs_rq *cfs_rq;
960 /* rq "owned" by this entity/group: */
961 struct cfs_rq *my_q;
962#endif
963};
Ingo Molnar70b97a72006-07-03 00:25:42 -0700964
Linus Torvalds1da177e2005-04-16 15:20:36 -0700965struct task_struct {
966 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
Roman Zippelf7e42172007-05-09 02:35:17 -0700967 void *stack;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968 atomic_t usage;
William Cohen97dc32c2007-05-08 00:23:41 -0700969 unsigned int flags; /* per process flags, defined below */
970 unsigned int ptrace;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700971
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -0700972 int lock_depth; /* BKL lock depth */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973
Peter Williams2dd73a42006-06-27 02:54:34 -0700974#ifdef CONFIG_SMP
975#ifdef __ARCH_WANT_UNLOCKED_CTXSW
Nick Piggin4866cde2005-06-25 14:57:23 -0700976 int oncpu;
977#endif
Peter Williams2dd73a42006-06-27 02:54:34 -0700978#endif
Ingo Molnar50e645a2007-07-09 18:52:00 +0200979
Ingo Molnarb29739f2006-06-27 02:54:51 -0700980 int prio, static_prio, normal_prio;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 struct list_head run_list;
Ingo Molnar5522d5d2007-10-15 17:00:12 +0200982 const struct sched_class *sched_class;
Ingo Molnar20b8a592007-07-09 18:51:58 +0200983 struct sched_entity se;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984
Avi Kivitye107be32007-07-26 13:40:43 +0200985#ifdef CONFIG_PREEMPT_NOTIFIERS
986 /* list of struct preempt_notifier: */
987 struct hlist_head preempt_notifiers;
988#endif
989
Jens Axboe22e2c502005-06-27 10:55:12 +0200990 unsigned short ioprio;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700991#ifdef CONFIG_BLK_DEV_IO_TRACE
Jens Axboe2056a782006-03-23 20:00:26 +0100992 unsigned int btrace_seq;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700993#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994
William Cohen97dc32c2007-05-08 00:23:41 -0700995 unsigned int policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 cpumask_t cpus_allowed;
Ingo Molnar50e645a2007-07-09 18:52:00 +0200997 unsigned int time_slice;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998
Chandra Seetharaman52f17b62006-07-14 00:24:38 -0700999#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000 struct sched_info sched_info;
1001#endif
1002
1003 struct list_head tasks;
1004 /*
1005 * ptrace_list/ptrace_children forms the list of my children
1006 * that were stolen by a ptracer.
1007 */
1008 struct list_head ptrace_children;
1009 struct list_head ptrace_list;
1010
1011 struct mm_struct *mm, *active_mm;
1012
1013/* task state */
1014 struct linux_binfmt *binfmt;
William Cohen97dc32c2007-05-08 00:23:41 -07001015 int exit_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 int exit_code, exit_signal;
1017 int pdeath_signal; /* The signal sent when the parent dies */
1018 /* ??? */
William Cohen97dc32c2007-05-08 00:23:41 -07001019 unsigned int personality;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020 unsigned did_exec:1;
1021 pid_t pid;
1022 pid_t tgid;
Arjan van de Ven0a4254052006-09-26 10:52:38 +02001023
1024#ifdef CONFIG_CC_STACKPROTECTOR
1025 /* Canary value for the -fstack-protector gcc feature */
1026 unsigned long stack_canary;
1027#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028 /*
1029 * pointers to (original) parent process, youngest child, younger sibling,
1030 * older sibling, respectively. (p->father can be replaced with
1031 * p->parent->pid)
1032 */
1033 struct task_struct *real_parent; /* real parent process (when being debugged) */
1034 struct task_struct *parent; /* parent process */
1035 /*
1036 * children/sibling forms the list of my children plus the
1037 * tasks I'm ptracing.
1038 */
1039 struct list_head children; /* list of my children */
1040 struct list_head sibling; /* linkage in my parent's children list */
1041 struct task_struct *group_leader; /* threadgroup leader */
1042
1043 /* PID/PID hash table linkage. */
Eric W. Biederman92476d72006-03-31 02:31:42 -08001044 struct pid_link pids[PIDTYPE_MAX];
Oleg Nesterov47e65322006-03-28 16:11:25 -08001045 struct list_head thread_group;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046
1047 struct completion *vfork_done; /* for vfork() */
1048 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1049 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1050
William Cohen97dc32c2007-05-08 00:23:41 -07001051 unsigned int rt_priority;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052 cputime_t utime, stime;
Laurent Vivier9ac52312007-10-15 17:00:19 +02001053 cputime_t gtime;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054 unsigned long nvcsw, nivcsw; /* context switch counts */
Tomas Janousek924b42d2007-07-15 23:39:42 -07001055 struct timespec start_time; /* monotonic time */
1056 struct timespec real_start_time; /* boot based time */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001057/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1058 unsigned long min_flt, maj_flt;
1059
1060 cputime_t it_prof_expires, it_virt_expires;
1061 unsigned long long it_sched_expires;
1062 struct list_head cpu_timers[3];
1063
1064/* process credentials */
1065 uid_t uid,euid,suid,fsuid;
1066 gid_t gid,egid,sgid,fsgid;
1067 struct group_info *group_info;
1068 kernel_cap_t cap_effective, cap_inheritable, cap_permitted;
1069 unsigned keep_capabilities:1;
1070 struct user_struct *user;
1071#ifdef CONFIG_KEYS
David Howellsb5f545c2006-01-08 01:02:47 -08001072 struct key *request_key_auth; /* assumed request_key authority */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001073 struct key *thread_keyring; /* keyring private to this thread */
David Howells3e301482005-06-23 22:00:56 -07001074 unsigned char jit_keyring; /* default keyring to attach requested keys to */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075#endif
Arjan van de Vene07e23e2006-09-26 10:52:36 +02001076 /*
1077 * fpu_counter contains the number of consecutive context switches
1078 * that the FPU is used. If this is over a threshold, the lazy fpu
1079 * saving becomes unlazy to save the trap. This is an unsigned char
1080 * so that after 256 times the counter wraps and the behavior turns
1081 * lazy again; this to deal with bursty apps that only use FPU for
1082 * a short time
1083 */
1084 unsigned char fpu_counter;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085 int oomkilladj; /* OOM kill score adjustment (bit shift). */
Paolo 'Blaisorblade' Giarrusso36772092005-05-05 16:16:12 -07001086 char comm[TASK_COMM_LEN]; /* executable name excluding path
1087 - access with [gs]et_task_comm (which lock
1088 it with task_lock())
1089 - initialized normally by flush_old_exec */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090/* file system info */
1091 int link_count, total_link_count;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -07001092#ifdef CONFIG_SYSVIPC
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093/* ipc stuff */
1094 struct sysv_sem sysvsem;
Alexey Dobriyan3d5b6fc2006-09-29 01:59:40 -07001095#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096/* CPU-specific state of this task */
1097 struct thread_struct thread;
1098/* filesystem information */
1099 struct fs_struct *fs;
1100/* open file information */
1101 struct files_struct *files;
Serge E. Hallyn1651e142006-10-02 02:18:08 -07001102/* namespaces */
Serge E. Hallynab516012006-10-02 02:18:06 -07001103 struct nsproxy *nsproxy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001104/* signal handlers */
1105 struct signal_struct *signal;
1106 struct sighand_struct *sighand;
1107
1108 sigset_t blocked, real_blocked;
David Woodhouse150256d2006-01-18 17:43:57 -08001109 sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 struct sigpending pending;
1111
1112 unsigned long sas_ss_sp;
1113 size_t sas_ss_size;
1114 int (*notifier)(void *priv);
1115 void *notifier_data;
1116 sigset_t *notifier_mask;
1117
1118 void *security;
1119 struct audit_context *audit_context;
1120 seccomp_t seccomp;
1121
1122/* Thread group tracking */
1123 u32 parent_exec_id;
1124 u32 self_exec_id;
1125/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
1126 spinlock_t alloc_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127
Ingo Molnarb29739f2006-06-27 02:54:51 -07001128 /* Protection of the PI data structures: */
1129 spinlock_t pi_lock;
1130
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001131#ifdef CONFIG_RT_MUTEXES
1132 /* PI waiters blocked on a rt_mutex held by this task */
1133 struct plist_head pi_waiters;
1134 /* Deadlock detection and priority inheritance handling */
1135 struct rt_mutex_waiter *pi_blocked_on;
Ingo Molnar23f78d4a2006-06-27 02:54:53 -07001136#endif
1137
Ingo Molnar408894e2006-01-09 15:59:20 -08001138#ifdef CONFIG_DEBUG_MUTEXES
1139 /* mutex deadlock detection */
1140 struct mutex_waiter *blocked_on;
1141#endif
Ingo Molnarde30a2b2006-07-03 00:24:42 -07001142#ifdef CONFIG_TRACE_IRQFLAGS
1143 unsigned int irq_events;
1144 int hardirqs_enabled;
1145 unsigned long hardirq_enable_ip;
1146 unsigned int hardirq_enable_event;
1147 unsigned long hardirq_disable_ip;
1148 unsigned int hardirq_disable_event;
1149 int softirqs_enabled;
1150 unsigned long softirq_disable_ip;
1151 unsigned int softirq_disable_event;
1152 unsigned long softirq_enable_ip;
1153 unsigned int softirq_enable_event;
1154 int hardirq_context;
1155 int softirq_context;
1156#endif
Ingo Molnarfbb9ce952006-07-03 00:24:50 -07001157#ifdef CONFIG_LOCKDEP
1158# define MAX_LOCK_DEPTH 30UL
1159 u64 curr_chain_key;
1160 int lockdep_depth;
1161 struct held_lock held_locks[MAX_LOCK_DEPTH];
1162 unsigned int lockdep_recursion;
1163#endif
Ingo Molnar408894e2006-01-09 15:59:20 -08001164
Linus Torvalds1da177e2005-04-16 15:20:36 -07001165/* journalling filesystem info */
1166 void *journal_info;
1167
Neil Brownd89d8792007-05-01 09:53:42 +02001168/* stacked block device info */
1169 struct bio *bio_list, **bio_tail;
1170
Linus Torvalds1da177e2005-04-16 15:20:36 -07001171/* VM state */
1172 struct reclaim_state *reclaim_state;
1173
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174 struct backing_dev_info *backing_dev_info;
1175
1176 struct io_context *io_context;
1177
1178 unsigned long ptrace_message;
1179 siginfo_t *last_siginfo; /* For ptrace use. */
1180/*
1181 * current io wait handle: wait queue entry to use for io waits
1182 * If this thread is processing aio, this points at the waitqueue
1183 * inside the currently handled kiocb. It may be NULL (i.e. default
1184 * to a stack based synchronous wait) if its doing sync IO.
1185 */
1186 wait_queue_t *io_wait;
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001187#ifdef CONFIG_TASK_XACCT
Linus Torvalds1da177e2005-04-16 15:20:36 -07001188/* i/o counters(bytes read/written, #syscalls */
1189 u64 rchar, wchar, syscr, syscw;
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001190#endif
Andrew Morton7c3ab732006-12-10 02:19:19 -08001191 struct task_io_accounting ioac;
Jay Lan8f0ab512006-09-30 23:28:59 -07001192#if defined(CONFIG_TASK_XACCT)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001193 u64 acct_rss_mem1; /* accumulated rss usage */
1194 u64 acct_vm_mem1; /* accumulated virtual memory usage */
Jay Landb5fed262006-09-30 23:29:00 -07001195 cputime_t acct_stimexpd;/* stime since last update */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001196#endif
1197#ifdef CONFIG_NUMA
1198 struct mempolicy *mempolicy;
1199 short il_next;
1200#endif
1201#ifdef CONFIG_CPUSETS
1202 struct cpuset *cpuset;
1203 nodemask_t mems_allowed;
1204 int cpuset_mems_generation;
Paul Jackson825a46a2006-03-24 03:16:03 -08001205 int cpuset_mem_spread_rotor;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001206#endif
Ingo Molnar0771dfe2006-03-27 01:16:22 -08001207 struct robust_list_head __user *robust_list;
Ingo Molnar34f192c2006-03-27 01:16:24 -08001208#ifdef CONFIG_COMPAT
1209 struct compat_robust_list_head __user *compat_robust_list;
1210#endif
Ingo Molnarc87e2832006-06-27 02:54:58 -07001211 struct list_head pi_state_list;
1212 struct futex_pi_state *pi_state_cache;
Ingo Molnar0771dfe2006-03-27 01:16:22 -08001213
Jens Axboe22e2c502005-06-27 10:55:12 +02001214 atomic_t fs_excl; /* holding fs exclusive resources */
Ingo Molnare56d0902006-01-08 01:01:37 -08001215 struct rcu_head rcu;
Jens Axboeb92ce552006-04-11 13:52:07 +02001216
1217 /*
1218 * cache last used pipe for splice
1219 */
1220 struct pipe_inode_info *splice_pipe;
Shailabh Nagarca74e922006-07-14 00:24:36 -07001221#ifdef CONFIG_TASK_DELAY_ACCT
1222 struct task_delay_info *delays;
1223#endif
Akinobu Mitaf4f154f2006-12-08 02:39:47 -08001224#ifdef CONFIG_FAULT_INJECTION
1225 int make_it_fail;
1226#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227};
1228
Ingo Molnare05606d2007-07-09 18:51:59 +02001229/*
1230 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1231 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1232 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1233 * values are inverted: lower p->prio value means higher priority.
1234 *
1235 * The MAX_USER_RT_PRIO value allows the actual maximum
1236 * RT priority to be separate from the value exported to
1237 * user-space. This allows kernel threads to set their
1238 * priority to a value higher than any user task. Note:
1239 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1240 */
1241
1242#define MAX_USER_RT_PRIO 100
1243#define MAX_RT_PRIO MAX_USER_RT_PRIO
1244
1245#define MAX_PRIO (MAX_RT_PRIO + 40)
1246#define DEFAULT_PRIO (MAX_RT_PRIO + 20)
1247
1248static inline int rt_prio(int prio)
1249{
1250 if (unlikely(prio < MAX_RT_PRIO))
1251 return 1;
1252 return 0;
1253}
1254
1255static inline int rt_task(struct task_struct *p)
1256{
1257 return rt_prio(p->prio);
1258}
1259
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260static inline pid_t process_group(struct task_struct *tsk)
1261{
1262 return tsk->signal->pgrp;
1263}
1264
Cedric Le Goater1ec320a2006-12-08 02:37:55 -08001265static inline pid_t signal_session(struct signal_struct *sig)
1266{
1267 return sig->__session;
1268}
1269
Cedric Le Goater937949d2006-12-08 02:37:54 -08001270static inline pid_t process_session(struct task_struct *tsk)
1271{
Cedric Le Goater1ec320a2006-12-08 02:37:55 -08001272 return signal_session(tsk->signal);
1273}
1274
1275static inline void set_signal_session(struct signal_struct *sig, pid_t session)
1276{
1277 sig->__session = session;
Cedric Le Goater937949d2006-12-08 02:37:54 -08001278}
1279
Eric W. Biederman22c935f2006-10-02 02:17:09 -07001280static inline struct pid *task_pid(struct task_struct *task)
1281{
1282 return task->pids[PIDTYPE_PID].pid;
1283}
1284
1285static inline struct pid *task_tgid(struct task_struct *task)
1286{
1287 return task->group_leader->pids[PIDTYPE_PID].pid;
1288}
1289
1290static inline struct pid *task_pgrp(struct task_struct *task)
1291{
1292 return task->group_leader->pids[PIDTYPE_PGID].pid;
1293}
1294
1295static inline struct pid *task_session(struct task_struct *task)
1296{
1297 return task->group_leader->pids[PIDTYPE_SID].pid;
1298}
1299
Linus Torvalds1da177e2005-04-16 15:20:36 -07001300/**
1301 * pid_alive - check that a task structure is not stale
1302 * @p: Task structure to be checked.
1303 *
1304 * Test if a process is not yet dead (at most zombie state)
1305 * If pid_alive fails, then pointers within the task structure
1306 * can be stale and must not be dereferenced.
1307 */
1308static inline int pid_alive(struct task_struct *p)
1309{
Eric W. Biederman92476d72006-03-31 02:31:42 -08001310 return p->pids[PIDTYPE_PID].pid != NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001311}
1312
Sukadev Bhattiproluf400e192006-09-29 02:00:07 -07001313/**
Henne32602592006-10-06 00:44:01 -07001314 * is_init - check if a task structure is init
1315 * @tsk: Task structure to be checked.
1316 *
1317 * Check if a task structure is the first user space task the kernel created.
Sukadev Bhattiproluf400e192006-09-29 02:00:07 -07001318 */
1319static inline int is_init(struct task_struct *tsk)
1320{
1321 return tsk->pid == 1;
1322}
1323
Cedric Le Goater9ec52092006-10-02 02:19:00 -07001324extern struct pid *cad_pid;
1325
Linus Torvalds1da177e2005-04-16 15:20:36 -07001326extern void free_task(struct task_struct *tsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
Ingo Molnare56d0902006-01-08 01:01:37 -08001328
Andrew Morton158d9eb2006-03-31 02:31:34 -08001329extern void __put_task_struct(struct task_struct *t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001330
1331static inline void put_task_struct(struct task_struct *t)
1332{
1333 if (atomic_dec_and_test(&t->usage))
Eric W. Biederman8c7904a2006-03-31 02:31:37 -08001334 __put_task_struct(t);
Ingo Molnare56d0902006-01-08 01:01:37 -08001335}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001336
1337/*
1338 * Per process flags
1339 */
1340#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
1341 /* Not implemented yet, only for 486*/
1342#define PF_STARTING 0x00000002 /* being created */
1343#define PF_EXITING 0x00000004 /* getting shut down */
Alexey Kuznetsov778e9a92007-06-08 13:47:00 -07001344#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1346#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1347#define PF_DUMPCORE 0x00000200 /* dumped core */
1348#define PF_SIGNALED 0x00000400 /* killed by a signal */
1349#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1350#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
1351#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001352#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1353#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1354#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1355#define PF_KSWAPD 0x00040000 /* I am kswapd */
1356#define PF_SWAPOFF 0x00080000 /* I am in swapoff */
1357#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
Jens Axboeb31dc662006-06-13 08:26:10 +02001358#define PF_BORROWED_MM 0x00200000 /* I am a kthread doing use_mm */
1359#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1360#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1361#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1362#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
Paul Jacksonc61afb12006-03-24 03:16:08 -08001363#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
Thomas Gleixner61a87122006-06-27 02:54:56 -07001364#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
Rafael J. Wysockiba96a0c2007-05-23 13:57:25 -07001365#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366
1367/*
1368 * Only the _current_ task can read/write to tsk->flags, but other
1369 * tasks can access tsk->flags in readonly mode for example
1370 * with tsk_used_math (like during threaded core dumping).
1371 * There is however an exception to this rule during ptrace
1372 * or during fork: the ptracer task is allowed to write to the
1373 * child->flags of its traced child (same goes for fork, the parent
1374 * can write to the child->flags), because we're guaranteed the
1375 * child is not running and in turn not changing child->flags
1376 * at the same time the parent does it.
1377 */
1378#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1379#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1380#define clear_used_math() clear_stopped_child_used_math(current)
1381#define set_used_math() set_stopped_child_used_math(current)
1382#define conditional_stopped_child_used_math(condition, child) \
1383 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1384#define conditional_used_math(condition) \
1385 conditional_stopped_child_used_math(condition, current)
1386#define copy_to_stopped_child_used_math(child) \
1387 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1388/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1389#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1390#define used_math() tsk_used_math(current)
1391
1392#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001393extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001395static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001396{
Paul Jackson4098f992005-10-30 15:03:21 -08001397 if (!cpu_isset(0, new_mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001398 return -EINVAL;
1399 return 0;
1400}
1401#endif
1402
1403extern unsigned long long sched_clock(void);
Ingo Molnare436d802007-07-19 21:28:35 +02001404
1405/*
1406 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1407 * clock constructed from sched_clock():
1408 */
1409extern unsigned long long cpu_clock(int cpu);
1410
Ingo Molnar36c8b582006-07-03 00:25:41 -07001411extern unsigned long long
Ingo Molnar41b86e92007-07-09 18:51:58 +02001412task_sched_runtime(struct task_struct *task);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413
1414/* sched_exec is called by processes performing an exec */
1415#ifdef CONFIG_SMP
1416extern void sched_exec(void);
1417#else
1418#define sched_exec() {}
1419#endif
1420
Ingo Molnar2aa44d02007-08-23 15:18:02 +02001421extern void sched_clock_idle_sleep_event(void);
1422extern void sched_clock_idle_wakeup_event(u64 delta_ns);
Ingo Molnarbb29ab22007-07-09 18:51:59 +02001423
Linus Torvalds1da177e2005-04-16 15:20:36 -07001424#ifdef CONFIG_HOTPLUG_CPU
1425extern void idle_task_exit(void);
1426#else
1427static inline void idle_task_exit(void) {}
1428#endif
1429
1430extern void sched_idle_next(void);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001431
Ingo Molnar2bd8e6d2007-10-15 17:00:02 +02001432#ifdef CONFIG_SCHED_DEBUG
Peter Zijlstra21805082007-08-25 18:41:53 +02001433extern unsigned int sysctl_sched_latency;
Peter Zijlstra5f6d858e2007-10-15 17:00:12 +02001434extern unsigned int sysctl_sched_nr_latency;
Ingo Molnarbf0f6f22007-07-09 18:51:58 +02001435extern unsigned int sysctl_sched_wakeup_granularity;
1436extern unsigned int sysctl_sched_batch_wakeup_granularity;
Ingo Molnarbf0f6f22007-07-09 18:51:58 +02001437extern unsigned int sysctl_sched_child_runs_first;
1438extern unsigned int sysctl_sched_features;
Ingo Molnarda84d962007-10-15 17:00:18 +02001439extern unsigned int sysctl_sched_migration_cost;
Ingo Molnar2bd8e6d2007-10-15 17:00:02 +02001440#endif
1441
1442extern unsigned int sysctl_sched_compat_yield;
Ingo Molnarbf0f6f22007-07-09 18:51:58 +02001443
Ingo Molnarb29739f2006-06-27 02:54:51 -07001444#ifdef CONFIG_RT_MUTEXES
Ingo Molnar36c8b582006-07-03 00:25:41 -07001445extern int rt_mutex_getprio(struct task_struct *p);
1446extern void rt_mutex_setprio(struct task_struct *p, int prio);
1447extern void rt_mutex_adjust_pi(struct task_struct *p);
Ingo Molnarb29739f2006-06-27 02:54:51 -07001448#else
Ingo Molnar36c8b582006-07-03 00:25:41 -07001449static inline int rt_mutex_getprio(struct task_struct *p)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001450{
1451 return p->normal_prio;
1452}
Thomas Gleixner95e02ca2006-06-27 02:55:02 -07001453# define rt_mutex_adjust_pi(p) do { } while (0)
Ingo Molnarb29739f2006-06-27 02:54:51 -07001454#endif
1455
Ingo Molnar36c8b582006-07-03 00:25:41 -07001456extern void set_user_nice(struct task_struct *p, long nice);
1457extern int task_prio(const struct task_struct *p);
1458extern int task_nice(const struct task_struct *p);
1459extern int can_nice(const struct task_struct *p, const int nice);
1460extern int task_curr(const struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461extern int idle_cpu(int cpu);
1462extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001463extern struct task_struct *idle_task(int cpu);
1464extern struct task_struct *curr_task(int cpu);
1465extern void set_curr_task(int cpu, struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466
1467void yield(void);
1468
1469/*
1470 * The default (Linux) execution domain.
1471 */
1472extern struct exec_domain default_exec_domain;
1473
1474union thread_union {
1475 struct thread_info thread_info;
1476 unsigned long stack[THREAD_SIZE/sizeof(long)];
1477};
1478
1479#ifndef __HAVE_ARCH_KSTACK_END
1480static inline int kstack_end(void *addr)
1481{
1482 /* Reliable end of stack detection:
1483 * Some APM bios versions misalign the stack
1484 */
1485 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1486}
1487#endif
1488
1489extern union thread_union init_thread_union;
1490extern struct task_struct init_task;
1491
1492extern struct mm_struct init_mm;
1493
1494#define find_task_by_pid(nr) find_task_by_pid_type(PIDTYPE_PID, nr)
1495extern struct task_struct *find_task_by_pid_type(int type, int pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496extern void __set_special_pids(pid_t session, pid_t pgrp);
1497
1498/* per-UID process charging. */
Cedric Le Goateracce2922007-07-15 23:40:59 -07001499extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001500static inline struct user_struct *get_uid(struct user_struct *u)
1501{
1502 atomic_inc(&u->__count);
1503 return u;
1504}
1505extern void free_uid(struct user_struct *);
1506extern void switch_uid(struct user_struct *);
Pavel Emelyanov28f300d2007-09-18 22:46:45 -07001507extern void release_uids(struct user_namespace *ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001508
1509#include <asm/current.h>
1510
Atsushi Nemoto3171a032006-09-29 02:00:32 -07001511extern void do_timer(unsigned long ticks);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001512
1513extern int FASTCALL(wake_up_state(struct task_struct * tsk, unsigned int state));
1514extern int FASTCALL(wake_up_process(struct task_struct * tsk));
1515extern void FASTCALL(wake_up_new_task(struct task_struct * tsk,
1516 unsigned long clone_flags));
1517#ifdef CONFIG_SMP
1518 extern void kick_process(struct task_struct *tsk);
1519#else
1520 static inline void kick_process(struct task_struct *tsk) { }
1521#endif
Ingo Molnarad46c2c2007-07-09 18:52:00 +02001522extern void sched_fork(struct task_struct *p, int clone_flags);
1523extern void sched_dead(struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001524
1525extern int in_group_p(gid_t);
1526extern int in_egroup_p(gid_t);
1527
1528extern void proc_caches_init(void);
1529extern void flush_signals(struct task_struct *);
Oleg Nesterov10ab8252007-05-09 02:34:37 -07001530extern void ignore_signals(struct task_struct *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001531extern void flush_signal_handlers(struct task_struct *, int force_default);
1532extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1533
1534static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1535{
1536 unsigned long flags;
1537 int ret;
1538
1539 spin_lock_irqsave(&tsk->sighand->siglock, flags);
1540 ret = dequeue_signal(tsk, mask, info);
1541 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1542
1543 return ret;
1544}
1545
1546extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1547 sigset_t *mask);
1548extern void unblock_all_signals(void);
1549extern void release_task(struct task_struct * p);
1550extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1551extern int send_group_sig_info(int, struct siginfo *, struct task_struct *);
1552extern int force_sigsegv(int, struct task_struct *);
1553extern int force_sig_info(int, struct siginfo *, struct task_struct *);
Eric W. Biedermanc4b92fc2006-10-02 02:17:10 -07001554extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1555extern int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1556extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
Eric W. Biederman2425c082006-10-02 02:17:28 -07001557extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
Eric W. Biedermanc4b92fc2006-10-02 02:17:10 -07001558extern int kill_pgrp(struct pid *pid, int sig, int priv);
1559extern int kill_pid(struct pid *pid, int sig, int priv);
Matthew Wilcoxc3de4b32007-02-09 08:11:47 -07001560extern int kill_proc_info(int, struct siginfo *, pid_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001561extern void do_notify_parent(struct task_struct *, int);
1562extern void force_sig(int, struct task_struct *);
1563extern void force_sig_specific(int, struct task_struct *);
1564extern int send_sig(int, struct task_struct *, int);
1565extern void zap_other_threads(struct task_struct *p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001566extern int kill_proc(pid_t, int, int);
1567extern struct sigqueue *sigqueue_alloc(void);
1568extern void sigqueue_free(struct sigqueue *);
1569extern int send_sigqueue(int, struct sigqueue *, struct task_struct *);
1570extern int send_group_sigqueue(int, struct sigqueue *, struct task_struct *);
Oleg Nesterov9ac95f22006-02-09 22:41:50 +03001571extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1573
Cedric Le Goater9ec52092006-10-02 02:19:00 -07001574static inline int kill_cad_pid(int sig, int priv)
1575{
1576 return kill_pid(cad_pid, sig, priv);
1577}
1578
Linus Torvalds1da177e2005-04-16 15:20:36 -07001579/* These can be the second arg to send_sig_info/send_group_sig_info. */
1580#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1581#define SEND_SIG_PRIV ((struct siginfo *) 1)
1582#define SEND_SIG_FORCED ((struct siginfo *) 2)
1583
Oleg Nesterov621d3122005-10-30 15:03:45 -08001584static inline int is_si_special(const struct siginfo *info)
1585{
1586 return info <= SEND_SIG_FORCED;
1587}
1588
Linus Torvalds1da177e2005-04-16 15:20:36 -07001589/* True if we are on the alternate signal stack. */
1590
1591static inline int on_sig_stack(unsigned long sp)
1592{
1593 return (sp - current->sas_ss_sp < current->sas_ss_size);
1594}
1595
1596static inline int sas_ss_flags(unsigned long sp)
1597{
1598 return (current->sas_ss_size == 0 ? SS_DISABLE
1599 : on_sig_stack(sp) ? SS_ONSTACK : 0);
1600}
1601
Linus Torvalds1da177e2005-04-16 15:20:36 -07001602/*
1603 * Routines for handling mm_structs
1604 */
1605extern struct mm_struct * mm_alloc(void);
1606
1607/* mmdrop drops the mm and the page tables */
1608extern void FASTCALL(__mmdrop(struct mm_struct *));
1609static inline void mmdrop(struct mm_struct * mm)
1610{
Ingo Molnar6fb43d72007-07-09 18:52:01 +02001611 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001612 __mmdrop(mm);
1613}
1614
1615/* mmput gets rid of the mappings and all user-space */
1616extern void mmput(struct mm_struct *);
1617/* Grab a reference to a task's mm, if it is not already going away */
1618extern struct mm_struct *get_task_mm(struct task_struct *task);
1619/* Remove the current tasks stale references to the old mm_struct */
1620extern void mm_release(struct task_struct *, struct mm_struct *);
1621
1622extern int copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
1623extern void flush_thread(void);
1624extern void exit_thread(void);
1625
Linus Torvalds1da177e2005-04-16 15:20:36 -07001626extern void exit_files(struct task_struct *);
Oleg Nesterov6b3934e2006-03-28 16:11:16 -08001627extern void __cleanup_signal(struct signal_struct *);
Oleg Nesterova7e53282006-03-28 16:11:27 -08001628extern void __cleanup_sighand(struct sighand_struct *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001629extern void exit_itimers(struct signal_struct *);
1630
1631extern NORET_TYPE void do_group_exit(int);
1632
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633extern void daemonize(const char *, ...);
1634extern int allow_signal(int);
1635extern int disallow_signal(int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636
1637extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
1638extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
Ingo Molnar36c8b582006-07-03 00:25:41 -07001639struct task_struct *fork_idle(int);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001640
1641extern void set_task_comm(struct task_struct *tsk, char *from);
1642extern void get_task_comm(char *to, struct task_struct *tsk);
1643
1644#ifdef CONFIG_SMP
Ingo Molnar36c8b582006-07-03 00:25:41 -07001645extern void wait_task_inactive(struct task_struct * p);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001646#else
1647#define wait_task_inactive(p) do { } while (0)
1648#endif
1649
1650#define remove_parent(p) list_del_init(&(p)->sibling)
Oleg Nesterov8fafabd2006-03-28 16:11:05 -08001651#define add_parent(p) list_add_tail(&(p)->sibling,&(p)->parent->children)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001652
Eric W. Biederman5e85d4a2006-04-18 22:20:16 -07001653#define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001654
1655#define for_each_process(p) \
1656 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
1657
1658/*
1659 * Careful: do_each_thread/while_each_thread is a double loop so
1660 * 'break' will not work as expected - use goto instead.
1661 */
1662#define do_each_thread(g, t) \
1663 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
1664
1665#define while_each_thread(g, t) \
1666 while ((t = next_thread(t)) != g)
1667
Eric W. Biedermande12a782006-04-10 17:16:49 -06001668/* de_thread depends on thread_group_leader not being a pid based check */
1669#define thread_group_leader(p) (p == p->group_leader)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670
Eric W. Biederman0804ef42006-10-02 02:17:04 -07001671/* Do to the insanities of de_thread it is possible for a process
1672 * to have the pid of the thread group leader without actually being
1673 * the thread group leader. For iteration through the pids in proc
1674 * all we care about is that we have a task with the appropriate
1675 * pid, we don't actually care if we have the right task.
1676 */
1677static inline int has_group_leader_pid(struct task_struct *p)
1678{
1679 return p->pid == p->tgid;
1680}
1681
Ingo Molnar36c8b582006-07-03 00:25:41 -07001682static inline struct task_struct *next_thread(const struct task_struct *p)
Oleg Nesterov47e65322006-03-28 16:11:25 -08001683{
1684 return list_entry(rcu_dereference(p->thread_group.next),
Ingo Molnar36c8b582006-07-03 00:25:41 -07001685 struct task_struct, thread_group);
Oleg Nesterov47e65322006-03-28 16:11:25 -08001686}
1687
Ingo Molnar36c8b582006-07-03 00:25:41 -07001688static inline int thread_group_empty(struct task_struct *p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689{
Oleg Nesterov47e65322006-03-28 16:11:25 -08001690 return list_empty(&p->thread_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001691}
1692
1693#define delay_group_leader(p) \
1694 (thread_group_leader(p) && !thread_group_empty(p))
1695
Linus Torvalds1da177e2005-04-16 15:20:36 -07001696/*
Eric W. Biederman260ea102006-06-23 02:05:18 -07001697 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
Jens Axboe22e2c502005-06-27 10:55:12 +02001698 * subscriptions and synchronises with wait4(). Also used in procfs. Also
Paul Jackson053199e2005-10-30 15:02:30 -08001699 * pins the final release of task.io_context. Also protects ->cpuset.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001700 *
1701 * Nests both inside and outside of read_lock(&tasklist_lock).
1702 * It must not be nested with write_lock_irq(&tasklist_lock),
1703 * neither inside nor outside.
1704 */
1705static inline void task_lock(struct task_struct *p)
1706{
1707 spin_lock(&p->alloc_lock);
1708}
1709
1710static inline void task_unlock(struct task_struct *p)
1711{
1712 spin_unlock(&p->alloc_lock);
1713}
1714
Oleg Nesterovf63ee722006-03-28 16:11:13 -08001715extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
1716 unsigned long *flags);
1717
1718static inline void unlock_task_sighand(struct task_struct *tsk,
1719 unsigned long *flags)
1720{
1721 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
1722}
1723
Al Virof0373602005-11-13 16:06:57 -08001724#ifndef __HAVE_THREAD_FUNCTIONS
1725
Roman Zippelf7e42172007-05-09 02:35:17 -07001726#define task_thread_info(task) ((struct thread_info *)(task)->stack)
1727#define task_stack_page(task) ((task)->stack)
Al Viroa1261f52005-11-13 16:06:55 -08001728
Al Viro10ebffd2005-11-13 16:06:56 -08001729static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
1730{
1731 *task_thread_info(p) = *task_thread_info(org);
1732 task_thread_info(p)->task = p;
1733}
1734
1735static inline unsigned long *end_of_stack(struct task_struct *p)
1736{
Roman Zippelf7e42172007-05-09 02:35:17 -07001737 return (unsigned long *)(task_thread_info(p) + 1);
Al Viro10ebffd2005-11-13 16:06:56 -08001738}
1739
Al Virof0373602005-11-13 16:06:57 -08001740#endif
1741
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742/* set thread flags in other task's structures
1743 * - see asm/thread_info.h for TIF_xxxx flags available
1744 */
1745static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1746{
Al Viroa1261f52005-11-13 16:06:55 -08001747 set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001748}
1749
1750static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1751{
Al Viroa1261f52005-11-13 16:06:55 -08001752 clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001753}
1754
1755static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1756{
Al Viroa1261f52005-11-13 16:06:55 -08001757 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001758}
1759
1760static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1761{
Al Viroa1261f52005-11-13 16:06:55 -08001762 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001763}
1764
1765static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1766{
Al Viroa1261f52005-11-13 16:06:55 -08001767 return test_ti_thread_flag(task_thread_info(tsk), flag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001768}
1769
1770static inline void set_tsk_need_resched(struct task_struct *tsk)
1771{
1772 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1773}
1774
1775static inline void clear_tsk_need_resched(struct task_struct *tsk)
1776{
1777 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1778}
1779
1780static inline int signal_pending(struct task_struct *p)
1781{
1782 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
1783}
1784
1785static inline int need_resched(void)
1786{
1787 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
1788}
1789
1790/*
1791 * cond_resched() and cond_resched_lock(): latency reduction via
1792 * explicit rescheduling in places that are safe. The return
1793 * value indicates whether a reschedule was done in fact.
1794 * cond_resched_lock() will drop the spinlock before scheduling,
1795 * cond_resched_softirq() will enable bhs before scheduling.
1796 */
1797extern int cond_resched(void);
1798extern int cond_resched_lock(spinlock_t * lock);
1799extern int cond_resched_softirq(void);
1800
1801/*
1802 * Does a critical section need to be broken due to another
1803 * task waiting?:
1804 */
1805#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
1806# define need_lockbreak(lock) ((lock)->break_lock)
1807#else
1808# define need_lockbreak(lock) 0
1809#endif
1810
1811/*
1812 * Does a critical section need to be broken due to another
1813 * task waiting or preemption being signalled:
1814 */
1815static inline int lock_need_resched(spinlock_t *lock)
1816{
1817 if (need_lockbreak(lock) || need_resched())
1818 return 1;
1819 return 0;
1820}
1821
Roland McGrath7bb44ad2007-05-23 13:57:44 -07001822/*
1823 * Reevaluate whether the task has signals pending delivery.
1824 * Wake the task if so.
1825 * This is required every time the blocked sigset_t changes.
1826 * callers must hold sighand->siglock.
1827 */
1828extern void recalc_sigpending_and_wake(struct task_struct *t);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001829extern void recalc_sigpending(void);
1830
1831extern void signal_wake_up(struct task_struct *t, int resume_stopped);
1832
1833/*
1834 * Wrappers for p->thread_info->cpu access. No-op on UP.
1835 */
1836#ifdef CONFIG_SMP
1837
1838static inline unsigned int task_cpu(const struct task_struct *p)
1839{
Al Viroa1261f52005-11-13 16:06:55 -08001840 return task_thread_info(p)->cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001841}
1842
Ingo Molnarc65cc872007-07-09 18:51:58 +02001843extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001844
1845#else
1846
1847static inline unsigned int task_cpu(const struct task_struct *p)
1848{
1849 return 0;
1850}
1851
1852static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1853{
1854}
1855
1856#endif /* CONFIG_SMP */
1857
1858#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1859extern void arch_pick_mmap_layout(struct mm_struct *mm);
1860#else
1861static inline void arch_pick_mmap_layout(struct mm_struct *mm)
1862{
1863 mm->mmap_base = TASK_UNMAPPED_BASE;
1864 mm->get_unmapped_area = arch_get_unmapped_area;
1865 mm->unmap_area = arch_unmap_area;
1866}
1867#endif
1868
1869extern long sched_setaffinity(pid_t pid, cpumask_t new_mask);
1870extern long sched_getaffinity(pid_t pid, cpumask_t *mask);
1871
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -07001872extern int sched_mc_power_savings, sched_smt_power_savings;
Siddha, Suresh B5c45bf22006-06-27 02:54:42 -07001873
Linus Torvalds1da177e2005-04-16 15:20:36 -07001874extern void normalize_rt_tasks(void);
1875
Srivatsa Vaddagiri9b5b7752007-10-15 17:00:09 +02001876#ifdef CONFIG_FAIR_GROUP_SCHED
1877
Ingo Molnar4cf86d72007-10-15 17:00:14 +02001878extern struct task_group init_task_group;
Srivatsa Vaddagiri9b5b7752007-10-15 17:00:09 +02001879
Ingo Molnar4cf86d72007-10-15 17:00:14 +02001880extern struct task_group *sched_create_group(void);
1881extern void sched_destroy_group(struct task_group *tg);
Srivatsa Vaddagiri9b5b7752007-10-15 17:00:09 +02001882extern void sched_move_task(struct task_struct *tsk);
Ingo Molnar4cf86d72007-10-15 17:00:14 +02001883extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
Dhaval Giani5cb350b2007-10-15 17:00:14 +02001884extern unsigned long sched_group_shares(struct task_group *tg);
Srivatsa Vaddagiri9b5b7752007-10-15 17:00:09 +02001885
1886#endif
1887
Alexey Dobriyan4b98d112007-02-10 01:46:45 -08001888#ifdef CONFIG_TASK_XACCT
1889static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
1890{
1891 tsk->rchar += amt;
1892}
1893
1894static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
1895{
1896 tsk->wchar += amt;
1897}
1898
1899static inline void inc_syscr(struct task_struct *tsk)
1900{
1901 tsk->syscr++;
1902}
1903
1904static inline void inc_syscw(struct task_struct *tsk)
1905{
1906 tsk->syscw++;
1907}
1908#else
1909static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
1910{
1911}
1912
1913static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
1914{
1915}
1916
1917static inline void inc_syscr(struct task_struct *tsk)
1918{
1919}
1920
1921static inline void inc_syscw(struct task_struct *tsk)
1922{
1923}
1924#endif
1925
Linus Torvalds1da177e2005-04-16 15:20:36 -07001926#endif /* __KERNEL__ */
1927
1928#endif