xref: /freebsd/sys/sys/taskqueue.h (revision bea256f3)
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/_cpuset.h>
39 
40 struct taskqueue;
41 struct taskqgroup;
42 struct proc;
43 struct thread;
44 
45 enum taskqueue_callback_type {
46 	TASKQUEUE_CALLBACK_TYPE_INIT,
47 	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN,
48 };
49 #define	TASKQUEUE_CALLBACK_TYPE_MIN	TASKQUEUE_CALLBACK_TYPE_INIT
50 #define	TASKQUEUE_CALLBACK_TYPE_MAX	TASKQUEUE_CALLBACK_TYPE_SHUTDOWN
51 #define	TASKQUEUE_NUM_CALLBACKS		TASKQUEUE_CALLBACK_TYPE_MAX + 1
52 #define	TASKQUEUE_NAMELEN		32
53 
54 /* taskqueue_enqueue flags */
55 #define	TASKQUEUE_FAIL_IF_PENDING	(1 << 0)
56 #define	TASKQUEUE_FAIL_IF_CANCELING	(1 << 1)
57 
58 typedef void (*taskqueue_callback_fn)(void *context);
59 
60 /*
61  * A notification callback function which is called from
62  * taskqueue_enqueue().  The context argument is given in the call to
63  * taskqueue_create().  This function would normally be used to allow the
64  * queue to arrange to run itself later (e.g., by scheduling a software
65  * interrupt or waking a kernel thread).
66  */
67 typedef void (*taskqueue_enqueue_fn)(void *context);
68 
69 struct taskqueue *taskqueue_create(const char *name, int mflags,
70 				    taskqueue_enqueue_fn enqueue,
71 				    void *context);
72 int	taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
73 	    const char *name, ...) __printflike(4, 5);
74 int	taskqueue_start_threads_in_proc(struct taskqueue **tqp, int count,
75 	    int pri, struct proc *p, const char *name, ...) __printflike(5, 6);
76 int	taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count,
77 	    int pri, cpuset_t *mask, const char *name, ...) __printflike(5, 6);
78 int	taskqueue_enqueue(struct taskqueue *queue, struct task *task);
79 int	taskqueue_enqueue_flags(struct taskqueue *queue, struct task *task,
80 	    int flags);
81 int	taskqueue_enqueue_timeout(struct taskqueue *queue,
82 	    struct timeout_task *timeout_task, int ticks);
83 int	taskqueue_enqueue_timeout_sbt(struct taskqueue *queue,
84 	    struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr,
85 	    int flags);
86 int	taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task);
87 int	taskqueue_cancel(struct taskqueue *queue, struct task *task,
88 	    u_int *pendp);
89 int	taskqueue_cancel_timeout(struct taskqueue *queue,
90 	    struct timeout_task *timeout_task, u_int *pendp);
91 void	taskqueue_drain(struct taskqueue *queue, struct task *task);
92 void	taskqueue_drain_timeout(struct taskqueue *queue,
93 	    struct timeout_task *timeout_task);
94 void	taskqueue_drain_all(struct taskqueue *queue);
95 void	taskqueue_quiesce(struct taskqueue *queue);
96 void	taskqueue_free(struct taskqueue *queue);
97 void	taskqueue_run(struct taskqueue *queue);
98 void	taskqueue_block(struct taskqueue *queue);
99 void	taskqueue_unblock(struct taskqueue *queue);
100 int	taskqueue_member(struct taskqueue *queue, struct thread *td);
101 void	taskqueue_set_callback(struct taskqueue *queue,
102 	    enum taskqueue_callback_type cb_type,
103 	    taskqueue_callback_fn callback, void *context);
104 
105 #define TASK_INITIALIZER(priority, func, context)	\
106 	{ .ta_priority = (priority),			\
107 	  .ta_func = (func),				\
108 	  .ta_context = (context) }
109 
110 /*
111  * Functions for dedicated thread taskqueues
112  */
113 void	taskqueue_thread_loop(void *arg);
114 void	taskqueue_thread_enqueue(void *context);
115 
116 /*
117  * Initialise a task structure.
118  */
119 #define TASK_INIT_FLAGS(task, priority, func, context, flags) do {	\
120 	(task)->ta_pending = 0;					\
121 	(task)->ta_priority = (priority);			\
122 	(task)->ta_flags = (flags);				\
123 	(task)->ta_func = (func);				\
124 	(task)->ta_context = (context);				\
125 } while (0)
126 
127 #define TASK_INIT(t, p, f, c)	TASK_INIT_FLAGS(t, p, f, c, 0)
128 
129 void _timeout_task_init(struct taskqueue *queue,
130 	    struct timeout_task *timeout_task, int priority, task_fn_t func,
131 	    void *context);
132 #define	TIMEOUT_TASK_INIT(queue, timeout_task, priority, func, context)	do { \
133 	_Static_assert((priority) >= 0 && (priority) <= 255,	\
134 	    "struct task priority is 8 bit in size");           \
135 	_timeout_task_init(queue, timeout_task, priority, func, context); \
136 } while (0)
137 
138 /*
139  * Declare a reference to a taskqueue.
140  */
141 #define TASKQUEUE_DECLARE(name)			\
142 extern struct taskqueue *taskqueue_##name
143 
144 /*
145  * Define and initialise a global taskqueue that uses sleep mutexes.
146  */
147 #define TASKQUEUE_DEFINE(name, enqueue, context, init)			\
148 									\
149 struct taskqueue *taskqueue_##name;					\
150 									\
151 static void								\
152 taskqueue_define_##name(void *arg)					\
153 {									\
154 	taskqueue_##name =						\
155 	    taskqueue_create(#name, M_WAITOK, (enqueue), (context));	\
156 	init;								\
157 }									\
158 									\
159 SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND,		\
160 	taskqueue_define_##name, NULL);					\
161 									\
162 struct __hack
163 #define TASKQUEUE_DEFINE_THREAD(name)					\
164 TASKQUEUE_DEFINE(name, taskqueue_thread_enqueue, &taskqueue_##name,	\
165 	taskqueue_start_threads(&taskqueue_##name, 1, PWAIT,		\
166 	"%s taskq", #name))
167 
168 /*
169  * Define and initialise a global taskqueue that uses spin mutexes.
170  */
171 #define TASKQUEUE_FAST_DEFINE(name, enqueue, context, init)		\
172 									\
173 struct taskqueue *taskqueue_##name;					\
174 									\
175 static void								\
176 taskqueue_define_##name(void *arg)					\
177 {									\
178 	taskqueue_##name =						\
179 	    taskqueue_create_fast(#name, M_WAITOK, (enqueue),		\
180 	    (context));							\
181 	init;								\
182 }									\
183 									\
184 SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND,		\
185 	taskqueue_define_##name, NULL);					\
186 									\
187 struct __hack
188 #define TASKQUEUE_FAST_DEFINE_THREAD(name)				\
189 TASKQUEUE_FAST_DEFINE(name, taskqueue_thread_enqueue,			\
190 	&taskqueue_##name, taskqueue_start_threads(&taskqueue_##name,	\
191 	1, PWAIT, "%s taskq", #name))
192 
193 /*
194  * These queues are serviced by software interrupt handlers.  To enqueue
195  * a task, call taskqueue_enqueue(taskqueue_swi, &task) or
196  * taskqueue_enqueue(taskqueue_swi_giant, &task).
197  */
198 TASKQUEUE_DECLARE(swi_giant);
199 TASKQUEUE_DECLARE(swi);
200 
201 /*
202  * This queue is serviced by a kernel thread.  To enqueue a task, call
203  * taskqueue_enqueue(taskqueue_thread, &task).
204  */
205 TASKQUEUE_DECLARE(thread);
206 
207 /*
208  * Queue for swi handlers dispatched from fast interrupt handlers.
209  * These are necessarily different from the above because the queue
210  * must be locked with spinlocks since sleep mutex's cannot be used
211  * from a fast interrupt handler context.
212  */
213 TASKQUEUE_DECLARE(fast);
214 struct taskqueue *taskqueue_create_fast(const char *name, int mflags,
215 				    taskqueue_enqueue_fn enqueue,
216 				    void *context);
217 
218 #endif /* !_SYS_TASKQUEUE_H_ */
219