2 * Copyright (c) 2000 Doug Rabson
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
26 * $FreeBSD: src/sys/sys/taskqueue.h,v 1.31 2011/12/19 18:55:13 jhb Exp $
29 #ifndef _SYS_TASKQUEUE_H_
30 #define _SYS_TASKQUEUE_H_
33 #error "This file should not be included by userland programs."
36 #include <sys/queue.h>
37 #include <sys/callout.h>
42 * Each task includes a function which is called from
43 * taskqueue_run(). The first argument is taken from the 'ta_context'
44 * field of struct task and the second argument is a count of how many
45 * times the task was enqueued before the call to taskqueue_run().
47 typedef void task_fn_t(void *context, int pending);
50 * A notification callback function which is called from
51 * taskqueue_enqueue(). The context argument is given in the call to
52 * taskqueue_create(). This function would normally be used to allow the
53 * queue to arrange to run itself later (e.g., by scheduling a software
54 * interrupt or waking a kernel thread).
56 typedef void (*taskqueue_enqueue_fn)(void *context);
59 STAILQ_ENTRY(task) ta_link; /* link for queue */
60 struct taskqueue *ta_queue;
61 int ta_pending; /* count times queued */
62 int ta_priority; /* priority of task in queue */
63 task_fn_t *ta_func; /* task handler */
64 void *ta_context; /* argument for handler */
73 struct taskqueue *taskqueue_create(const char *name, int mflags,
74 taskqueue_enqueue_fn enqueue,
76 int taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
77 int ncpu, const char *name, ...)
79 int taskqueue_enqueue(struct taskqueue *queue, struct task *task);
80 int taskqueue_enqueue_optq(struct taskqueue *queue,
81 struct taskqueue **qpp, struct task *task);
82 int taskqueue_enqueue_timeout(struct taskqueue *queue,
83 struct timeout_task *timeout_task, int ticks);
84 int taskqueue_cancel(struct taskqueue *queue, struct task *task,
86 int taskqueue_cancel_simple(struct task *task);
87 int taskqueue_cancel_timeout(struct taskqueue *queue,
88 struct timeout_task *timeout_task, u_int *pendp);
89 void taskqueue_drain(struct taskqueue *queue, struct task *task);
90 void taskqueue_drain_simple(struct task *task);
91 void taskqueue_drain_timeout(struct taskqueue *queue,
92 struct timeout_task *timeout_task);
93 struct taskqueue *taskqueue_find(const char *name);
94 void taskqueue_free(struct taskqueue *queue);
95 void taskqueue_block(struct taskqueue *queue);
96 void taskqueue_unblock(struct taskqueue *queue);
98 #define TASK_INITIALIZER(priority, func, context) \
101 .ta_priority = (priority), \
103 .ta_context = (context) }
106 * Functions for dedicated thread taskqueues
108 void taskqueue_thread_loop(void *arg);
109 void taskqueue_thread_enqueue(void *context);
112 * Initialise a task structure.
114 #define TASK_INIT(task, priority, func, context) do { \
115 (task)->ta_queue = NULL; \
116 (task)->ta_pending = 0; \
117 (task)->ta_priority = (priority); \
118 (task)->ta_func = (func); \
119 (task)->ta_context = (context); \
122 void _timeout_task_init(struct taskqueue *queue,
123 struct timeout_task *timeout_task, int priority, task_fn_t func,
125 #define TIMEOUT_TASK_INIT(queue, timeout_task, priority, func, context) \
126 _timeout_task_init(queue, timeout_task, priority, func, context);
129 * Declare a reference to a taskqueue.
131 #define TASKQUEUE_DECLARE(name) \
132 extern struct taskqueue *taskqueue_##name
135 * Define and initialise a taskqueue.
137 #define TASKQUEUE_DEFINE(name, enqueue, context, init) \
139 struct taskqueue *taskqueue_##name; \
142 taskqueue_define_##name(void *arg) \
145 taskqueue_create(#name, M_INTWAIT, (enqueue), (context)); \
149 SYSINIT(taskqueue_##name, SI_SUB_PRE_DRIVERS, SI_ORDER_SECOND, \
150 taskqueue_define_##name, NULL); \
154 #define TASKQUEUE_DEFINE_THREAD(name) \
155 TASKQUEUE_DEFINE(name, taskqueue_thread_enqueue, &taskqueue_##name, \
156 taskqueue_start_threads(&taskqueue_##name, 1, \
157 TDPRI_KERN_DAEMON, -1, "%s taskq", #name))
159 * This queue is serviced by a software interrupt handler. To enqueue
160 * a task, call taskqueue_enqueue(taskqueue_swi, &task).
162 TASKQUEUE_DECLARE(swi);
163 TASKQUEUE_DECLARE(swi_mp);
166 * This queue is serviced by a per-cpu kernel thread. To enqueue a task, call
167 * taskqueue_enqueue(taskqueue_thread[mycpuid], &task).
169 extern struct taskqueue *taskqueue_thread[];
171 #endif /* !_SYS_TASKQUEUE_H_ */