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1#ifndef _LINUX_SCHED_TASK_H 2#define _LINUX_SCHED_TASK_H 3 4/* 5 * Interface between the scheduler and various task lifetime (fork()/exit()) 6 * functionality: 7 */ 8 9#include <linux/sched.h> 10 11struct task_struct; 12struct rusage; 13union thread_union; 14 15/* 16 * This serializes "schedule()" and also protects 17 * the run-queue from deletions/modifications (but 18 * _adding_ to the beginning of the run-queue has 19 * a separate lock). 20 */ 21extern rwlock_t tasklist_lock; 22extern spinlock_t mmlist_lock; 23 24extern union thread_union init_thread_union; 25extern struct task_struct init_task; 26 27#ifdef CONFIG_PROVE_RCU 28extern int lockdep_tasklist_lock_is_held(void); 29#endif /* #ifdef CONFIG_PROVE_RCU */ 30 31extern asmlinkage void schedule_tail(struct task_struct *prev); 32extern void init_idle(struct task_struct *idle, int cpu); 33 34extern int sched_fork(unsigned long clone_flags, struct task_struct *p); 35extern void sched_dead(struct task_struct *p); 36 37void __noreturn do_task_dead(void); 38 39extern void proc_caches_init(void); 40 41extern void release_task(struct task_struct * p); 42 43#ifdef CONFIG_HAVE_COPY_THREAD_TLS 44extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, 45 struct task_struct *, unsigned long); 46#else 47extern int copy_thread(unsigned long, unsigned long, unsigned long, 48 struct task_struct *); 49 50/* Architectures that haven't opted into copy_thread_tls get the tls argument 51 * via pt_regs, so ignore the tls argument passed via C. */ 52static inline int copy_thread_tls( 53 unsigned long clone_flags, unsigned long sp, unsigned long arg, 54 struct task_struct *p, unsigned long tls) 55{ 56 return copy_thread(clone_flags, sp, arg, p); 57} 58#endif 59extern void flush_thread(void); 60 61#ifdef CONFIG_HAVE_EXIT_THREAD 62extern void exit_thread(struct task_struct *tsk); 63#else 64static inline void exit_thread(struct task_struct *tsk) 65{ 66} 67#endif 68extern void do_group_exit(int); 69 70extern void exit_files(struct task_struct *); 71extern void exit_itimers(struct signal_struct *); 72 73extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long); 74extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); 75struct task_struct *fork_idle(int); 76extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 77extern long kernel_wait4(pid_t, int *, int, struct rusage *); 78 79extern void free_task(struct task_struct *tsk); 80 81/* sched_exec is called by processes performing an exec */ 82#ifdef CONFIG_SMP 83extern void sched_exec(void); 84#else 85#define sched_exec() {} 86#endif 87 88#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) 89 90extern void __put_task_struct(struct task_struct *t); 91 92static inline void put_task_struct(struct task_struct *t) 93{ 94 if (atomic_dec_and_test(&t->usage)) 95 __put_task_struct(t); 96} 97 98struct task_struct *task_rcu_dereference(struct task_struct **ptask); 99 100#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT 101extern int arch_task_struct_size __read_mostly; 102#else 103# define arch_task_struct_size (sizeof(struct task_struct)) 104#endif 105 106#ifdef CONFIG_VMAP_STACK 107static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t) 108{ 109 return t->stack_vm_area; 110} 111#else 112static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t) 113{ 114 return NULL; 115} 116#endif 117 118/* 119 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring 120 * subscriptions and synchronises with wait4(). Also used in procfs. Also 121 * pins the final release of task.io_context. Also protects ->cpuset and 122 * ->cgroup.subsys[]. And ->vfork_done. 123 * 124 * Nests both inside and outside of read_lock(&tasklist_lock). 125 * It must not be nested with write_lock_irq(&tasklist_lock), 126 * neither inside nor outside. 127 */ 128static inline void task_lock(struct task_struct *p) 129{ 130 spin_lock(&p->alloc_lock); 131} 132 133static inline void task_unlock(struct task_struct *p) 134{ 135 spin_unlock(&p->alloc_lock); 136} 137 138#endif /* _LINUX_SCHED_TASK_H */