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
41struct taskqueue;
42struct taskqgroup;
43struct proc;
44struct thread;
45
46struct timeout_task {
47	struct taskqueue *q;
48	struct task t;
49	struct callout c;
50	int    f;
51};
52
53enum 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
66typedef 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 */
75typedef void (*taskqueue_enqueue_fn)(void *context);
76
77struct taskqueue *taskqueue_create(const char *name, int mflags,
78				    taskqueue_enqueue_fn enqueue,
79				    void *context);
80int	taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
81	    const char *name, ...) __printflike(4, 5);
82int	taskqueue_start_threads_in_proc(struct taskqueue **tqp, int count,
83	    int pri, struct proc *p, const char *name, ...) __printflike(5, 6);
84int	taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count,
85	    int pri, cpuset_t *mask, const char *name, ...) __printflike(5, 6);
86int	taskqueue_enqueue(struct taskqueue *queue, struct task *task);
87int	taskqueue_enqueue_flags(struct taskqueue *queue, struct task *task,
88	    int flags);
89int	taskqueue_enqueue_timeout(struct taskqueue *queue,
90	    struct timeout_task *timeout_task, int ticks);
91int	taskqueue_enqueue_timeout_sbt(struct taskqueue *queue,
92	    struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr,
93	    int flags);
94int	taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task);
95int	taskqueue_cancel(struct taskqueue *queue, struct task *task,
96	    u_int *pendp);
97int	taskqueue_cancel_timeout(struct taskqueue *queue,
98	    struct timeout_task *timeout_task, u_int *pendp);
99void	taskqueue_drain(struct taskqueue *queue, struct task *task);
100void	taskqueue_drain_timeout(struct taskqueue *queue,
101	    struct timeout_task *timeout_task);
102void	taskqueue_drain_all(struct taskqueue *queue);
103void	taskqueue_quiesce(struct taskqueue *queue);
104void	taskqueue_free(struct taskqueue *queue);
105void	taskqueue_run(struct taskqueue *queue);
106void	taskqueue_block(struct taskqueue *queue);
107void	taskqueue_unblock(struct taskqueue *queue);
108int	taskqueue_member(struct taskqueue *queue, struct thread *td);
109void	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 */
121void	taskqueue_thread_loop(void *arg);
122void	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
137void _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)			\
150extern 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									\
157struct taskqueue *taskqueue_##name;					\
158									\
159static void								\
160taskqueue_define_##name(void *arg)					\
161{									\
162	taskqueue_##name =						\
163	    taskqueue_create(#name, M_WAITOK, (enqueue), (context));	\
164	init;								\
165}									\
166									\
167SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND,		\
168	taskqueue_define_##name, NULL);					\
169									\
170struct __hack
171#define TASKQUEUE_DEFINE_THREAD(name)					\
172TASKQUEUE_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									\
181struct taskqueue *taskqueue_##name;					\
182									\
183static void								\
184taskqueue_define_##name(void *arg)					\
185{									\
186	taskqueue_##name =						\
187	    taskqueue_create_fast(#name, M_WAITOK, (enqueue),		\
188	    (context));							\
189	init;								\
190}									\
191									\
192SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND,		\
193	taskqueue_define_##name, NULL);					\
194									\
195struct __hack
196#define TASKQUEUE_FAST_DEFINE_THREAD(name)				\
197TASKQUEUE_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 */
206TASKQUEUE_DECLARE(swi_giant);
207TASKQUEUE_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 */
213TASKQUEUE_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 */
221TASKQUEUE_DECLARE(fast);
222struct taskqueue *taskqueue_create_fast(const char *name, int mflags,
223				    taskqueue_enqueue_fn enqueue,
224				    void *context);
225
226#endif /* !_SYS_TASKQUEUE_H_ */
227