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
40struct taskqueue;
41struct taskqgroup;
42struct proc;
43struct thread;
44
45enum 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
58typedef 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 */
67typedef void (*taskqueue_enqueue_fn)(void *context);
68
69struct taskqueue *taskqueue_create(const char *name, int mflags,
70 taskqueue_enqueue_fn enqueue,
71 void *context);
72int taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
73 const char *name, ...) __printflike(4, 5);
74int taskqueue_start_threads_in_proc(struct taskqueue **tqp, int count,
75 int pri, struct proc *p, const char *name, ...) __printflike(5, 6);
76int taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count,
77 int pri, cpuset_t *mask, const char *name, ...) __printflike(5, 6);
78int taskqueue_enqueue(struct taskqueue *queue, struct task *task);
79int taskqueue_enqueue_flags(struct taskqueue *queue, struct task *task,
80 int flags);
81int taskqueue_enqueue_timeout(struct taskqueue *queue,
82 struct timeout_task *timeout_task, int ticks);
83int taskqueue_enqueue_timeout_sbt(struct taskqueue *queue,
84 struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr,
85 int flags);
86int taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task);
87int taskqueue_cancel(struct taskqueue *queue, struct task *task,
88 u_int *pendp);
89int taskqueue_cancel_timeout(struct taskqueue *queue,
90 struct timeout_task *timeout_task, u_int *pendp);
91void taskqueue_drain(struct taskqueue *queue, struct task *task);
92void taskqueue_drain_timeout(struct taskqueue *queue,
93 struct timeout_task *timeout_task);
94void taskqueue_drain_all(struct taskqueue *queue);
95void taskqueue_quiesce(struct taskqueue *queue);
96void taskqueue_free(struct taskqueue *queue);
97void taskqueue_run(struct taskqueue *queue);
98void taskqueue_block(struct taskqueue *queue);
99void taskqueue_unblock(struct taskqueue *queue);
100int taskqueue_member(struct taskqueue *queue, struct thread *td);
101void 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 */
113void taskqueue_thread_loop(void *arg);
114void 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
129void _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) \
142extern 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 \
149struct taskqueue *taskqueue_##name; \
150 \
151static void \
152taskqueue_define_##name(void *arg) \
153{ \
154 taskqueue_##name = \
155 taskqueue_create(#name, M_WAITOK, (enqueue), (context)); \
156 init; \
157} \
158 \
159SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND, \
160 taskqueue_define_##name, NULL); \
161 \
162struct __hack
163#define TASKQUEUE_DEFINE_THREAD(name) \
164TASKQUEUE_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 \
173struct taskqueue *taskqueue_##name; \
174 \
175static void \
176taskqueue_define_##name(void *arg) \
177{ \
178 taskqueue_##name = \
179 taskqueue_create_fast(#name, M_WAITOK, (enqueue), \
180 (context)); \
181 init; \
182} \
183 \
184SYSINIT(taskqueue_##name, SI_SUB_TASKQ, SI_ORDER_SECOND, \
185 taskqueue_define_##name, NULL); \
186 \
187struct __hack
188#define TASKQUEUE_FAST_DEFINE_THREAD(name) \
189TASKQUEUE_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 */
198TASKQUEUE_DECLARE(swi_giant);
199TASKQUEUE_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 */
205TASKQUEUE_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 */
213TASKQUEUE_DECLARE(fast);
214struct taskqueue *taskqueue_create_fast(const char *name, int mflags,
215 taskqueue_enqueue_fn enqueue,
216 void *context);
217
218/*
219 * This queue is used to process asynchronous device events such as
220 * hot plug insertion and removal of devices.
221 */
222TASKQUEUE_DECLARE(bus);
223
224#endif /* !_SYS_TASKQUEUE_H_ */