regulator: tps65090: convert regualtor_init_data as pointer
[linux-2.6.git] / include / linux / kthread.h
1 #ifndef _LINUX_KTHREAD_H
2 #define _LINUX_KTHREAD_H
3 /* Simple interface for creating and stopping kernel threads without mess. */
4 #include <linux/err.h>
5 #include <linux/sched.h>
6
7 struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
8                                            void *data,
9                                            int node,
10                                            const char namefmt[], ...)
11         __attribute__((format(printf, 4, 5)));
12
13 #define kthread_create(threadfn, data, namefmt, arg...) \
14         kthread_create_on_node(threadfn, data, -1, namefmt, ##arg)
15
16
17 /**
18  * kthread_run - create and wake a thread.
19  * @threadfn: the function to run until signal_pending(current).
20  * @data: data ptr for @threadfn.
21  * @namefmt: printf-style name for the thread.
22  *
23  * Description: Convenient wrapper for kthread_create() followed by
24  * wake_up_process().  Returns the kthread or ERR_PTR(-ENOMEM).
25  */
26 #define kthread_run(threadfn, data, namefmt, ...)                          \
27 ({                                                                         \
28         struct task_struct *__k                                            \
29                 = kthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \
30         if (!IS_ERR(__k))                                                  \
31                 wake_up_process(__k);                                      \
32         __k;                                                               \
33 })
34
35 void kthread_bind(struct task_struct *k, unsigned int cpu);
36 int kthread_stop(struct task_struct *k);
37 int kthread_should_stop(void);
38 void *kthread_data(struct task_struct *k);
39
40 int kthreadd(void *unused);
41 extern struct task_struct *kthreadd_task;
42 extern int tsk_fork_get_node(struct task_struct *tsk);
43
44 /*
45  * Simple work processor based on kthread.
46  *
47  * This provides easier way to make use of kthreads.  A kthread_work
48  * can be queued and flushed using queue/flush_kthread_work()
49  * respectively.  Queued kthread_works are processed by a kthread
50  * running kthread_worker_fn().
51  *
52  * A kthread_work can't be freed while it is executing.
53  */
54 struct kthread_work;
55 typedef void (*kthread_work_func_t)(struct kthread_work *work);
56
57 struct kthread_worker {
58         spinlock_t              lock;
59         struct list_head        work_list;
60         struct task_struct      *task;
61 };
62
63 struct kthread_work {
64         struct list_head        node;
65         kthread_work_func_t     func;
66         wait_queue_head_t       done;
67         atomic_t                flushing;
68         int                     queue_seq;
69         int                     done_seq;
70 };
71
72 #define KTHREAD_WORKER_INIT(worker)     {                               \
73         .lock = __SPIN_LOCK_UNLOCKED((worker).lock),                    \
74         .work_list = LIST_HEAD_INIT((worker).work_list),                \
75         }
76
77 #define KTHREAD_WORK_INIT(work, fn)     {                               \
78         .node = LIST_HEAD_INIT((work).node),                            \
79         .func = (fn),                                                   \
80         .done = __WAIT_QUEUE_HEAD_INITIALIZER((work).done),             \
81         .flushing = ATOMIC_INIT(0),                                     \
82         }
83
84 #define DEFINE_KTHREAD_WORKER(worker)                                   \
85         struct kthread_worker worker = KTHREAD_WORKER_INIT(worker)
86
87 #define DEFINE_KTHREAD_WORK(work, fn)                                   \
88         struct kthread_work work = KTHREAD_WORK_INIT(work, fn)
89
90 /*
91  * kthread_worker.lock and kthread_work.done need their own lockdep class
92  * keys if they are defined on stack with lockdep enabled.  Use the
93  * following macros when defining them on stack.
94  */
95 #ifdef CONFIG_LOCKDEP
96 # define KTHREAD_WORKER_INIT_ONSTACK(worker)                            \
97         ({ init_kthread_worker(&worker); worker; })
98 # define DEFINE_KTHREAD_WORKER_ONSTACK(worker)                          \
99         struct kthread_worker worker = KTHREAD_WORKER_INIT_ONSTACK(worker)
100 # define KTHREAD_WORK_INIT_ONSTACK(work, fn)                            \
101         ({ init_kthread_work((&work), fn); work; })
102 # define DEFINE_KTHREAD_WORK_ONSTACK(work, fn)                          \
103         struct kthread_work work = KTHREAD_WORK_INIT_ONSTACK(work, fn)
104 #else
105 # define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker)
106 # define DEFINE_KTHREAD_WORK_ONSTACK(work, fn) DEFINE_KTHREAD_WORK(work, fn)
107 #endif
108
109 extern void __init_kthread_worker(struct kthread_worker *worker,
110                         const char *name, struct lock_class_key *key);
111
112 #define init_kthread_worker(worker)                                     \
113         do {                                                            \
114                 static struct lock_class_key __key;                     \
115                 __init_kthread_worker((worker), "("#worker")->lock", &__key); \
116         } while (0)
117
118 #define init_kthread_work(work, fn)                                     \
119         do {                                                            \
120                 memset((work), 0, sizeof(struct kthread_work));         \
121                 INIT_LIST_HEAD(&(work)->node);                          \
122                 (work)->func = (fn);                                    \
123                 init_waitqueue_head(&(work)->done);                     \
124         } while (0)
125
126 int kthread_worker_fn(void *worker_ptr);
127
128 bool queue_kthread_work(struct kthread_worker *worker,
129                         struct kthread_work *work);
130 void flush_kthread_work(struct kthread_work *work);
131 void flush_kthread_worker(struct kthread_worker *worker);
132
133 #endif /* _LINUX_KTHREAD_H */