xref: /freebsd/sys/sys/taskqueue.h (revision 95ee2897)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2000 Doug Rabson
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, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
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 proc;
44 struct thread;
45 
46 struct timeout_task {
47 	struct taskqueue *q;
48 	struct task t;
49 	struct callout c;
50 	int    f;
51 };
52 
53 enum taskqueue_callback_type {
54 	TASKQUEUE_CALLBACK_TYPE_INIT,
55 	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN,
56 };
57 #define	TASKQUEUE_CALLBACK_TYPE_MIN	TASKQUEUE_CALLBACK_TYPE_INIT
58 #define	TASKQUEUE_CALLBACK_TYPE_MAX	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN
59 #define	TASKQUEUE_NUM_CALLBACKS		TASKQUEUE_CALLBACK_TYPE_MAX + 1
60 #define	TASKQUEUE_NAMELEN		32
61 
62 /* taskqueue_enqueue flags */
63 #define	TASKQUEUE_FAIL_IF_PENDING	(1 << 0)
64 #define	TASKQUEUE_FAIL_IF_CANCELING	(1 << 1)
65 
66 typedef void (*taskqueue_callback_fn)(void *context);
67 
68 /*
69  * A notification callback function which is called from
70  * taskqueue_enqueue().  The context argument is given in the call to
71  * taskqueue_create().  This function would normally be used to allow the
72  * queue to arrange to run itself later (e.g., by scheduling a software
73  * interrupt or waking a kernel thread).
74  */
75 typedef void (*taskqueue_enqueue_fn)(void *context);
76 
77 struct taskqueue *taskqueue_create(const char *name, int mflags,
78 				    taskqueue_enqueue_fn enqueue,
79 				    void *context);
80 int	taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
81 	    const char *name, ...) __printflike(4, 5);
82 int	taskqueue_start_threads_in_proc(struct taskqueue **tqp, int count,
83 	    int pri, struct proc *p, const char *name, ...) __printflike(5, 6);
84 int	taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count,
85 	    int pri, cpuset_t *mask, const char *name, ...) __printflike(5, 6);
86 int	taskqueue_enqueue(struct taskqueue *queue, struct task *task);
87 int	taskqueue_enqueue_flags(struct taskqueue *queue, struct task *task,
88 	    int flags);
89 int	taskqueue_enqueue_timeout(struct taskqueue *queue,
90 	    struct timeout_task *timeout_task, int ticks);
91 int	taskqueue_enqueue_timeout_sbt(struct taskqueue *queue,
92 	    struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr,
93 	    int flags);
94 int	taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task);
95 int	taskqueue_cancel(struct taskqueue *queue, struct task *task,
96 	    u_int *pendp);
97 int	taskqueue_cancel_timeout(struct taskqueue *queue,
98 	    struct timeout_task *timeout_task, u_int *pendp);
99 void	taskqueue_drain(struct taskqueue *queue, struct task *task);
100 void	taskqueue_drain_timeout(struct taskqueue *queue,
101 	    struct timeout_task *timeout_task);
102 void	taskqueue_drain_all(struct taskqueue *queue);
103 void	taskqueue_quiesce(struct taskqueue *queue);
104 void	taskqueue_free(struct taskqueue *queue);
105 void	taskqueue_run(struct taskqueue *queue);
106 void	taskqueue_block(struct taskqueue *queue);
107 void	taskqueue_unblock(struct taskqueue *queue);
108 int	taskqueue_member(struct taskqueue *queue, struct thread *td);
109 void	taskqueue_set_callback(struct taskqueue *queue,
110 	    enum taskqueue_callback_type cb_type,
111 	    taskqueue_callback_fn callback, void *context);
112 
113 #define TASK_INITIALIZER(priority, func, context)	\
114 	{ .ta_priority = (priority),			\
115 	  .ta_func = (func),				\
116 	  .ta_context = (context) }
117 
118 /*
119  * Functions for dedicated thread taskqueues
120  */
121 void	taskqueue_thread_loop(void *arg);
122 void	taskqueue_thread_enqueue(void *context);
123 
124 /*
125  * Initialise a task structure.
126  */
127 #define TASK_INIT_FLAGS(task, priority, func, context, flags) do {	\
128 	(task)->ta_pending = 0;					\
129 	(task)->ta_priority = (priority);			\
130 	(task)->ta_flags = (flags);				\
131 	(task)->ta_func = (func);				\
132 	(task)->ta_context = (context);				\
133 } while (0)
134 
135 #define TASK_INIT(t, p, f, c)	TASK_INIT_FLAGS(t, p, f, c, 0)
136 
137 void _timeout_task_init(struct taskqueue *queue,
138 	    struct timeout_task *timeout_task, int priority, task_fn_t func,
139 	    void *context);
140 #define	TIMEOUT_TASK_INIT(queue, timeout_task, priority, func, context)	do { \
141 	_Static_assert((priority) >= 0 && (priority) <= 255,	\
142 	    "struct task priority is 8 bit in size");           \
143 	_timeout_task_init(queue, timeout_task, priority, func, context); \
144 } while (0)
145 
146 /*
147  * Declare a reference to a taskqueue.
148  */
149 #define TASKQUEUE_DECLARE(name)			\
150 extern struct taskqueue *taskqueue_##name
151 
152 /*
153  * Define and initialise a global taskqueue that uses sleep mutexes.
154  */
155 #define TASKQUEUE_DEFINE(name, enqueue, context, init)			\
156 									\
157 struct taskqueue *taskqueue_##name;					\
158 									\
159 static void								\
160 taskqueue_define_##name(void *arg)					\
161 {									\
162 	taskqueue_##name =						\
163 	    taskqueue_create(#name, M_WAITOK, (enqueue), (context));	\
164 	init;								\
165 }									\
166 									\
167 SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND,		\
168 	taskqueue_define_##name, NULL);					\
169 									\
170 struct __hack
171 #define TASKQUEUE_DEFINE_THREAD(name)					\
172 TASKQUEUE_DEFINE(name, taskqueue_thread_enqueue, &taskqueue_##name,	\
173 	taskqueue_start_threads(&taskqueue_##name, 1, PWAIT,		\
174 	"%s taskq", #name))
175 
176 /*
177  * Define and initialise a global taskqueue that uses spin mutexes.
178  */
179 #define TASKQUEUE_FAST_DEFINE(name, enqueue, context, init)		\
180 									\
181 struct taskqueue *taskqueue_##name;					\
182 									\
183 static void								\
184 taskqueue_define_##name(void *arg)					\
185 {									\
186 	taskqueue_##name =						\
187 	    taskqueue_create_fast(#name, M_WAITOK, (enqueue),		\
188 	    (context));							\
189 	init;								\
190 }									\
191 									\
192 SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND,		\
193 	taskqueue_define_##name, NULL);					\
194 									\
195 struct __hack
196 #define TASKQUEUE_FAST_DEFINE_THREAD(name)				\
197 TASKQUEUE_FAST_DEFINE(name, taskqueue_thread_enqueue,			\
198 	&taskqueue_##name, taskqueue_start_threads(&taskqueue_##name,	\
199 	1, PWAIT, "%s taskq", #name))
200 
201 /*
202  * These queues are serviced by software interrupt handlers.  To enqueue
203  * a task, call taskqueue_enqueue(taskqueue_swi, &task) or
204  * taskqueue_enqueue(taskqueue_swi_giant, &task).
205  */
206 TASKQUEUE_DECLARE(swi_giant);
207 TASKQUEUE_DECLARE(swi);
208 
209 /*
210  * This queue is serviced by a kernel thread.  To enqueue a task, call
211  * taskqueue_enqueue(taskqueue_thread, &task).
212  */
213 TASKQUEUE_DECLARE(thread);
214 
215 /*
216  * Queue for swi handlers dispatched from fast interrupt handlers.
217  * These are necessarily different from the above because the queue
218  * must be locked with spinlocks since sleep mutex's cannot be used
219  * from a fast interrupt handler context.
220  */
221 TASKQUEUE_DECLARE(fast);
222 struct taskqueue *taskqueue_create_fast(const char *name, int mflags,
223 				    taskqueue_enqueue_fn enqueue,
224 				    void *context);
225 
226 #endif /* !_SYS_TASKQUEUE_H_ */
227