1/*-
2 * Copyright (c) 2000 Doug Rabson
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29#ifndef _SYS_TASKQUEUE_H_
30#define _SYS_TASKQUEUE_H_
31
32#ifndef _KERNEL
33#error "no user-servicable parts inside"
34#endif
35
36#include <sys/queue.h>
37#include <sys/_task.h>
38#include <sys/_callout.h>
39
40struct taskqueue;
41struct taskqgroup;
42struct thread;
43
44struct timeout_task {
45	struct taskqueue *q;
46	struct task t;
47	struct callout c;
48	int    f;
49};
50
51enum taskqueue_callback_type {
52	TASKQUEUE_CALLBACK_TYPE_INIT,
53	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN,
54};
55#define	TASKQUEUE_CALLBACK_TYPE_MIN	TASKQUEUE_CALLBACK_TYPE_INIT
56#define	TASKQUEUE_CALLBACK_TYPE_MAX	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN
57#define	TASKQUEUE_NUM_CALLBACKS		TASKQUEUE_CALLBACK_TYPE_MAX + 1
58#define	TASKQUEUE_NAMELEN		32
59
60typedef void (*taskqueue_callback_fn)(void *context);
61
62/*
63 * A notification callback function which is called from
64 * taskqueue_enqueue().  The context argument is given in the call to
65 * taskqueue_create().  This function would normally be used to allow the
66 * queue to arrange to run itself later (e.g., by scheduling a software
67 * interrupt or waking a kernel thread).
68 */
69typedef void (*taskqueue_enqueue_fn)(void *context);
70
71struct taskqueue *taskqueue_create(const char *name, int mflags,
72					taskqueue_enqueue_fn enqueue,
73					void *context);
74int	taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
75				const char *name, ...) __printflike(4, 5);
76int	taskqueue_enqueue(struct taskqueue *queue, struct task *task);
77int	taskqueue_enqueue_timeout(struct taskqueue *queue,
78		struct timeout_task *timeout_task, int _ticks);
79int	taskqueue_cancel(struct taskqueue *queue, struct task *task,
80		u_int *pendp);
81int	taskqueue_cancel_timeout(struct taskqueue *queue,
82		struct timeout_task *timeout_task, u_int *pendp);
83void	taskqueue_drain(struct taskqueue *queue, struct task *task);
84void	taskqueue_drain_timeout(struct taskqueue *queue,
85		struct timeout_task *timeout_task);
86void	taskqueue_drain_all(struct taskqueue *queue);
87void	taskqueue_free(struct taskqueue *queue);
88void	taskqueue_run(struct taskqueue *queue);
89void	taskqueue_block(struct taskqueue *queue);
90void	taskqueue_unblock(struct taskqueue *queue);
91int	taskqueue_member(struct taskqueue *queue, struct thread *td);
92void	taskqueue_set_callback(struct taskqueue *queue,
93		enum taskqueue_callback_type cb_type,
94		taskqueue_callback_fn callback, void *context);
95
96/*
97 * Functions for dedicated thread taskqueues
98 */
99void	taskqueue_thread_loop(void *arg);
100void	taskqueue_thread_enqueue(void *context);
101
102/*
103 * Initialise a task structure.
104 */
105void _task_init(struct task *, int prio, task_fn_t handler, void *arg);
106#define TASK_INIT(taskp, prio, hand, arg) _task_init(taskp, prio, hand, arg)
107#define NET_TASK_INIT TASK_INIT
108
109void _timeout_task_init(struct taskqueue *queue,
110		struct timeout_task *timeout_task, int priority, task_fn_t func,
111		void *context);
112#define	TIMEOUT_TASK_INIT(queue, timeout_task, priority, func, context) \
113	_timeout_task_init(queue, timeout_task, priority, func, context);
114
115/*
116 * Declare a reference to a taskqueue.
117 */
118#define TASKQUEUE_DECLARE(name)			\
119extern struct taskqueue *taskqueue_##name
120
121/*
122 * Define and initialise a global taskqueue that uses sleep mutexes.
123 */
124#define TASKQUEUE_DEFINE(name, enqueue, context, init)			\
125									\
126struct taskqueue *taskqueue_##name;					\
127									\
128static void								\
129taskqueue_define_##name(void *arg)					\
130{									\
131	taskqueue_##name =						\
132		taskqueue_create(#name, M_WAITOK, (enqueue), (context));	\
133	init;								\
134}									\
135									\
136SYSINIT(taskqueue_##name, SI_SUB_INIT_IF, SI_ORDER_SECOND,		\
137	taskqueue_define_##name, NULL);					\
138									\
139struct __hack
140#define TASKQUEUE_DEFINE_THREAD(name)					\
141TASKQUEUE_DEFINE(name, taskqueue_thread_enqueue, &taskqueue_##name,	\
142	taskqueue_start_threads(&taskqueue_##name, 1, PWAIT,		\
143	"%s taskq", #name))
144
145/*
146 * Define and initialise a global taskqueue that uses spin mutexes.
147 */
148#define TASKQUEUE_FAST_DEFINE(name, enqueue, context, init)		\
149									\
150struct taskqueue *taskqueue_##name;					\
151									\
152static void								\
153taskqueue_define_##name(void *arg)					\
154{									\
155	taskqueue_##name =						\
156		taskqueue_create_fast(#name, M_WAITOK, (enqueue),		\
157		(context));							\
158	init;								\
159}									\
160									\
161SYSINIT(taskqueue_##name, SI_SUB_INIT_IF, SI_ORDER_SECOND,		\
162	taskqueue_define_##name, NULL);					\
163									\
164struct __hack
165#define TASKQUEUE_FAST_DEFINE_THREAD(name)				\
166TASKQUEUE_FAST_DEFINE(name, taskqueue_thread_enqueue,			\
167	&taskqueue_##name, taskqueue_start_threads(&taskqueue_##name	\
168	1, PWAIT, "%s taskq", #name))
169
170/*
171 * These queues are serviced by software interrupt handlers.  To enqueue
172 * a task, call taskqueue_enqueue(taskqueue_swi, &task) or
173 * taskqueue_enqueue(taskqueue_swi_giant, &task).
174 */
175TASKQUEUE_DECLARE(swi_giant);
176TASKQUEUE_DECLARE(swi);
177
178/*
179 * This queue is serviced by a kernel thread.  To enqueue a task, call
180 * taskqueue_enqueue(taskqueue_thread, &task).
181 */
182TASKQUEUE_DECLARE(thread);
183
184/*
185 * Queue for swi handlers dispatched from fast interrupt handlers.
186 * These are necessarily different from the above because the queue
187 * must be locked with spinlocks since sleep mutex's cannot be used
188 * from a fast interrupt handler context.
189 */
190TASKQUEUE_DECLARE(fast);
191struct taskqueue *taskqueue_create_fast(const char *name, int mflags,
192					taskqueue_enqueue_fn enqueue,
193					void *context);
194
195#endif /* !_SYS_TASKQUEUE_H_ */
196