kthread.h revision 256281 
1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice unmodified, this list of conditions, and the following
12 *    disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28#ifndef	_LINUX_KTHREAD_H_
29#define	_LINUX_KTHREAD_H_
30
31#include <sys/param.h>
32#include <sys/lock.h>
33#include <sys/mutex.h>
34#include <sys/kernel.h>
35#include <sys/kthread.h>
36#include <sys/sleepqueue.h>
37
38#include <linux/slab.h>
39#include <linux/sched.h>
40
41static inline void
42_kthread_fn(void *arg)
43{
44	struct task_struct *task;
45
46	task = arg;
47	task_struct_set(curthread, task);
48	if (task->should_stop == 0)
49		task->task_ret = task->task_fn(task->task_data);
50	PROC_LOCK(task->task_thread->td_proc);
51	task->should_stop = TASK_STOPPED;
52	wakeup(task);
53	PROC_UNLOCK(task->task_thread->td_proc);
54	kthread_exit();
55}
56
57static inline struct task_struct *
58_kthread_create(int (*threadfn)(void *data), void *data)
59{
60	struct task_struct *task;
61
62	task = kzalloc(sizeof(*task), GFP_KERNEL);
63	task->task_fn = threadfn;
64	task->task_data = data;
65
66	return (task);
67}
68
69struct task_struct *kthread_create(int (*threadfn)(void *data),
70                                   void *data,
71                                   const char namefmt[], ...)
72        __attribute__((format(printf, 3, 4)));
73
74#define	kthread_run(fn, data, fmt, ...)					\
75({									\
76	struct task_struct *_task;					\
77									\
78	_task = _kthread_create((fn), (data));				\
79	if (kthread_add(_kthread_fn, _task, NULL, &_task->task_thread,	\
80	    0, 0, fmt, ## __VA_ARGS__)) {				\
81		kfree(_task);						\
82		_task = NULL;						\
83	} else								\
84		task_struct_set(_task->task_thread, _task);		\
85	_task;								\
86})
87
88#define	kthread_should_stop()	current->should_stop
89
90static inline int
91kthread_stop(struct task_struct *task)
92{
93
94	PROC_LOCK(task->task_thread->td_proc);
95	task->should_stop = TASK_SHOULD_STOP;
96	wake_up_process(task);
97	while (task->should_stop != TASK_STOPPED)
98		msleep(task, &task->task_thread->td_proc->p_mtx, PWAIT,
99		    "kstop", hz);
100	PROC_UNLOCK(task->task_thread->td_proc);
101	return task->task_ret;
102}
103
104#endif	/* _LINUX_KTHREAD_H_ */
105