Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
7struct task_struct *kthread_create(int (*threadfn)(void *data),
8 void *data,
9 const char namefmt[], ...)
10 __attribute__((format(printf, 3, 4)));
11
12/**
13 * kthread_run - create and wake a thread.
14 * @threadfn: the function to run until signal_pending(current).
15 * @data: data ptr for @threadfn.
16 * @namefmt: printf-style name for the thread.
17 *
18 * Description: Convenient wrapper for kthread_create() followed by
19 * wake_up_process(). Returns the kthread or ERR_PTR(-ENOMEM).
20 */
21#define kthread_run(threadfn, data, namefmt, ...) \
22({ \
23 struct task_struct *__k \
24 = kthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \
25 if (!IS_ERR(__k)) \
26 wake_up_process(__k); \
27 __k; \
28})
29
30void kthread_bind(struct task_struct *k, unsigned int cpu);
31int kthread_stop(struct task_struct *k);
32int kthread_should_stop(void);
33void *kthread_data(struct task_struct *k);
34
35int kthreadd(void *unused);
36extern struct task_struct *kthreadd_task;
37
38/*
39 * Simple work processor based on kthread.
40 *
41 * This provides easier way to make use of kthreads. A kthread_work
42 * can be queued and flushed using queue/flush_kthread_work()
43 * respectively. Queued kthread_works are processed by a kthread
44 * running kthread_worker_fn().
45 *
46 * A kthread_work can't be freed while it is executing.
47 */
48struct kthread_work;
49typedef void (*kthread_work_func_t)(struct kthread_work *work);
50
51struct kthread_worker {
52 spinlock_t lock;
53 struct list_head work_list;
54 struct task_struct *task;
55};
56
57struct kthread_work {
58 struct list_head node;
59 kthread_work_func_t func;
60 wait_queue_head_t done;
61 atomic_t flushing;
62 int queue_seq;
63 int done_seq;
64};
65
66#define KTHREAD_WORKER_INIT(worker) { \
67 .lock = SPIN_LOCK_UNLOCKED, \
68 .work_list = LIST_HEAD_INIT((worker).work_list), \
69 }
70
71#define KTHREAD_WORK_INIT(work, fn) { \
72 .node = LIST_HEAD_INIT((work).node), \
73 .func = (fn), \
74 .done = __WAIT_QUEUE_HEAD_INITIALIZER((work).done), \
75 .flushing = ATOMIC_INIT(0), \
76 }
77
78#define DEFINE_KTHREAD_WORKER(worker) \
79 struct kthread_worker worker = KTHREAD_WORKER_INIT(worker)
80
81#define DEFINE_KTHREAD_WORK(work, fn) \
82 struct kthread_work work = KTHREAD_WORK_INIT(work, fn)
83
84/*
85 * kthread_worker.lock and kthread_work.done need their own lockdep class
86 * keys if they are defined on stack with lockdep enabled. Use the
87 * following macros when defining them on stack.
88 */
89#ifdef CONFIG_LOCKDEP
90# define KTHREAD_WORKER_INIT_ONSTACK(worker) \
91 ({ init_kthread_worker(&worker); worker; })
92# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) \
93 struct kthread_worker worker = KTHREAD_WORKER_INIT_ONSTACK(worker)
94# define KTHREAD_WORK_INIT_ONSTACK(work, fn) \
95 ({ init_kthread_work((&work), fn); work; })
96# define DEFINE_KTHREAD_WORK_ONSTACK(work, fn) \
97 struct kthread_work work = KTHREAD_WORK_INIT_ONSTACK(work, fn)
98#else
99# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker)
100# define DEFINE_KTHREAD_WORK_ONSTACK(work, fn) DEFINE_KTHREAD_WORK(work, fn)
101#endif
102
103extern void __init_kthread_worker(struct kthread_worker *worker,
104 const char *name, struct lock_class_key *key);
105
106#define init_kthread_worker(worker) \
107 do { \
108 static struct lock_class_key __key; \
109 __init_kthread_worker((worker), "("#worker")->lock", &__key); \
110 } while (0)
111
112#define init_kthread_work(work, fn) \
113 do { \
114 memset((work), 0, sizeof(struct kthread_work)); \
115 INIT_LIST_HEAD(&(work)->node); \
116 (work)->func = (fn); \
117 init_waitqueue_head(&(work)->done); \
118 } while (0)
119
120int kthread_worker_fn(void *worker_ptr);
121
122bool queue_kthread_work(struct kthread_worker *worker,
123 struct kthread_work *work);
124void flush_kthread_work(struct kthread_work *work);
125void flush_kthread_worker(struct kthread_worker *worker);
126
127#endif /* _LINUX_KTHREAD_H */