xref: /freebsd/sys/sys/taskqueue.h (revision d93a896e)
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-serviceable parts inside"
34 #endif
35 
36 #include <sys/queue.h>
37 #include <sys/_task.h>
38 #include <sys/_callout.h>
39 #include <sys/_cpuset.h>
40 
41 struct taskqueue;
42 struct taskqgroup;
43 struct thread;
44 
45 struct timeout_task {
46 	struct taskqueue *q;
47 	struct task t;
48 	struct callout c;
49 	int    f;
50 };
51 
52 enum taskqueue_callback_type {
53 	TASKQUEUE_CALLBACK_TYPE_INIT,
54 	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN,
55 };
56 #define	TASKQUEUE_CALLBACK_TYPE_MIN	TASKQUEUE_CALLBACK_TYPE_INIT
57 #define	TASKQUEUE_CALLBACK_TYPE_MAX	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN
58 #define	TASKQUEUE_NUM_CALLBACKS		TASKQUEUE_CALLBACK_TYPE_MAX + 1
59 #define	TASKQUEUE_NAMELEN		32
60 
61 typedef void (*taskqueue_callback_fn)(void *context);
62 
63 /*
64  * A notification callback function which is called from
65  * taskqueue_enqueue().  The context argument is given in the call to
66  * taskqueue_create().  This function would normally be used to allow the
67  * queue to arrange to run itself later (e.g., by scheduling a software
68  * interrupt or waking a kernel thread).
69  */
70 typedef void (*taskqueue_enqueue_fn)(void *context);
71 
72 struct taskqueue *taskqueue_create(const char *name, int mflags,
73 				    taskqueue_enqueue_fn enqueue,
74 				    void *context);
75 int	taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
76 				const char *name, ...) __printflike(4, 5);
77 int	taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count,
78 	    int pri, cpuset_t *mask, const char *name, ...) __printflike(5, 6);
79 int	taskqueue_enqueue(struct taskqueue *queue, struct task *task);
80 int	taskqueue_enqueue_timeout(struct taskqueue *queue,
81 	    struct timeout_task *timeout_task, int ticks);
82 int	taskqueue_enqueue_timeout_sbt(struct taskqueue *queue,
83 	    struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr,
84 	    int flags);
85 int	taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task);
86 int	taskqueue_cancel(struct taskqueue *queue, struct task *task,
87 	    u_int *pendp);
88 int	taskqueue_cancel_timeout(struct taskqueue *queue,
89 	    struct timeout_task *timeout_task, u_int *pendp);
90 void	taskqueue_drain(struct taskqueue *queue, struct task *task);
91 void	taskqueue_drain_timeout(struct taskqueue *queue,
92 	    struct timeout_task *timeout_task);
93 void	taskqueue_drain_all(struct taskqueue *queue);
94 void	taskqueue_free(struct taskqueue *queue);
95 void	taskqueue_run(struct taskqueue *queue);
96 void	taskqueue_block(struct taskqueue *queue);
97 void	taskqueue_unblock(struct taskqueue *queue);
98 int	taskqueue_member(struct taskqueue *queue, struct thread *td);
99 void	taskqueue_set_callback(struct taskqueue *queue,
100 	    enum taskqueue_callback_type cb_type,
101 	    taskqueue_callback_fn callback, void *context);
102 
103 #define TASK_INITIALIZER(priority, func, context)	\
104 	{ .ta_pending = 0,				\
105 	  .ta_priority = (priority),			\
106 	  .ta_func = (func),				\
107 	  .ta_context = (context) }
108 
109 /*
110  * Functions for dedicated thread taskqueues
111  */
112 void	taskqueue_thread_loop(void *arg);
113 void	taskqueue_thread_enqueue(void *context);
114 
115 /*
116  * Initialise a task structure.
117  */
118 #define TASK_INIT(task, priority, func, context) do {	\
119 	(task)->ta_pending = 0;				\
120 	(task)->ta_priority = (priority);		\
121 	(task)->ta_func = (func);			\
122 	(task)->ta_context = (context);			\
123 } while (0)
124 
125 void _timeout_task_init(struct taskqueue *queue,
126 	    struct timeout_task *timeout_task, int priority, task_fn_t func,
127 	    void *context);
128 #define	TIMEOUT_TASK_INIT(queue, timeout_task, priority, func, context) \
129 	_timeout_task_init(queue, timeout_task, priority, func, context);
130 
131 /*
132  * Declare a reference to a taskqueue.
133  */
134 #define TASKQUEUE_DECLARE(name)			\
135 extern struct taskqueue *taskqueue_##name
136 
137 /*
138  * Define and initialise a global taskqueue that uses sleep mutexes.
139  */
140 #define TASKQUEUE_DEFINE(name, enqueue, context, init)			\
141 									\
142 struct taskqueue *taskqueue_##name;					\
143 									\
144 static void								\
145 taskqueue_define_##name(void *arg)					\
146 {									\
147 	taskqueue_##name =						\
148 	    taskqueue_create(#name, M_WAITOK, (enqueue), (context));	\
149 	init;								\
150 }									\
151 									\
152 SYSINIT(taskqueue_##name, SI_SUB_INIT_IF, SI_ORDER_SECOND,		\
153 	taskqueue_define_##name, NULL);					\
154 									\
155 struct __hack
156 #define TASKQUEUE_DEFINE_THREAD(name)					\
157 TASKQUEUE_DEFINE(name, taskqueue_thread_enqueue, &taskqueue_##name,	\
158 	taskqueue_start_threads(&taskqueue_##name, 1, PWAIT,		\
159 	"%s taskq", #name))
160 
161 /*
162  * Define and initialise a global taskqueue that uses spin mutexes.
163  */
164 #define TASKQUEUE_FAST_DEFINE(name, enqueue, context, init)		\
165 									\
166 struct taskqueue *taskqueue_##name;					\
167 									\
168 static void								\
169 taskqueue_define_##name(void *arg)					\
170 {									\
171 	taskqueue_##name =						\
172 	    taskqueue_create_fast(#name, M_WAITOK, (enqueue),		\
173 	    (context));							\
174 	init;								\
175 }									\
176 									\
177 SYSINIT(taskqueue_##name, SI_SUB_INIT_IF, SI_ORDER_SECOND,		\
178 	taskqueue_define_##name, NULL);					\
179 									\
180 struct __hack
181 #define TASKQUEUE_FAST_DEFINE_THREAD(name)				\
182 TASKQUEUE_FAST_DEFINE(name, taskqueue_thread_enqueue,			\
183 	&taskqueue_##name, taskqueue_start_threads(&taskqueue_##name	\
184 	1, PWAIT, "%s taskq", #name))
185 
186 /*
187  * These queues are serviced by software interrupt handlers.  To enqueue
188  * a task, call taskqueue_enqueue(taskqueue_swi, &task) or
189  * taskqueue_enqueue(taskqueue_swi_giant, &task).
190  */
191 TASKQUEUE_DECLARE(swi_giant);
192 TASKQUEUE_DECLARE(swi);
193 
194 /*
195  * This queue is serviced by a kernel thread.  To enqueue a task, call
196  * taskqueue_enqueue(taskqueue_thread, &task).
197  */
198 TASKQUEUE_DECLARE(thread);
199 
200 /*
201  * Queue for swi handlers dispatched from fast interrupt handlers.
202  * These are necessarily different from the above because the queue
203  * must be locked with spinlocks since sleep mutex's cannot be used
204  * from a fast interrupt handler context.
205  */
206 TASKQUEUE_DECLARE(fast);
207 struct taskqueue *taskqueue_create_fast(const char *name, int mflags,
208 				    taskqueue_enqueue_fn enqueue,
209 				    void *context);
210 
211 #endif /* !_SYS_TASKQUEUE_H_ */
212