taskqueue.h revision 177253
1/*- 2 * Copyright (c) 2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 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. 13 * 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 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/sys/taskqueue.h 177253 2008-03-16 10:58:09Z rwatson $ 27 */ 28 29#ifndef _SYS_TASKQUEUE_H_ 30#define _SYS_TASKQUEUE_H_ 31 32#ifndef _KERNEL 33#error "no user-servicable parts inside" 34#endif 35 36#include <sys/queue.h> 37#include <sys/_task.h> 38 39struct taskqueue; 40 41/* 42 * A notification callback function which is called from 43 * taskqueue_enqueue(). The context argument is given in the call to 44 * taskqueue_create(). This function would normally be used to allow the 45 * queue to arrange to run itself later (e.g., by scheduling a software 46 * interrupt or waking a kernel thread). 47 */ 48typedef void (*taskqueue_enqueue_fn)(void *context); 49 50struct proc; 51struct taskqueue *taskqueue_create(const char *name, int mflags, 52 taskqueue_enqueue_fn enqueue, 53 void *context); 54int taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 55 const char *name, ...) __printflike(4, 5); 56int taskqueue_enqueue(struct taskqueue *queue, struct task *task); 57void taskqueue_drain(struct taskqueue *queue, struct task *task); 58struct taskqueue *taskqueue_find(const char *name); 59void taskqueue_free(struct taskqueue *queue); 60void taskqueue_run(struct taskqueue *queue); 61 62/* 63 * Functions for dedicated thread taskqueues 64 */ 65void taskqueue_thread_loop(void *arg); 66void taskqueue_thread_enqueue(void *context); 67 68/* 69 * Initialise a task structure. 70 */ 71#define TASK_INIT(task, priority, func, context) do { \ 72 (task)->ta_pending = 0; \ 73 (task)->ta_priority = (priority); \ 74 (task)->ta_func = (func); \ 75 (task)->ta_context = (context); \ 76} while (0) 77 78/* 79 * Declare a reference to a taskqueue. 80 */ 81#define TASKQUEUE_DECLARE(name) \ 82extern struct taskqueue *taskqueue_##name 83 84/* 85 * Define and initialise a global taskqueue that uses sleep mutexes. 86 */ 87#define TASKQUEUE_DEFINE(name, enqueue, context, init) \ 88 \ 89struct taskqueue *taskqueue_##name; \ 90 \ 91static void \ 92taskqueue_define_##name(void *arg) \ 93{ \ 94 taskqueue_##name = \ 95 taskqueue_create(#name, M_NOWAIT, (enqueue), (context)); \ 96 init; \ 97} \ 98 \ 99SYSINIT(taskqueue_##name, SI_SUB_CONFIGURE, SI_ORDER_SECOND, \ 100 taskqueue_define_##name, NULL); \ 101 \ 102struct __hack 103#define TASKQUEUE_DEFINE_THREAD(name) \ 104TASKQUEUE_DEFINE(name, taskqueue_thread_enqueue, &taskqueue_##name, \ 105 taskqueue_start_threads(&taskqueue_##name, 1, PWAIT, \ 106 "%s taskq", #name)) 107 108/* 109 * Define and initialise a global taskqueue that uses spin mutexes. 110 */ 111#define TASKQUEUE_FAST_DEFINE(name, enqueue, context, init) \ 112 \ 113struct taskqueue *taskqueue_##name; \ 114 \ 115static void \ 116taskqueue_define_##name(void *arg) \ 117{ \ 118 taskqueue_##name = \ 119 taskqueue_create_fast(#name, M_NOWAIT, (enqueue), \ 120 (context)); \ 121 init; \ 122} \ 123 \ 124SYSINIT(taskqueue_##name, SI_SUB_CONFIGURE, SI_ORDER_SECOND, \ 125 taskqueue_define_##name, NULL); \ 126 \ 127struct __hack 128#define TASKQUEUE_FAST_DEFINE_THREAD(name) \ 129TASKQUEUE_FAST_DEFINE(name, taskqueue_thread_enqueue, \ 130 &taskqueue_##name, taskqueue_start_threads(&taskqueue_##name \ 131 1, PWAIT, "%s taskq", #name)) 132 133/* 134 * These queues are serviced by software interrupt handlers. To enqueue 135 * a task, call taskqueue_enqueue(taskqueue_swi, &task) or 136 * taskqueue_enqueue(taskqueue_swi_giant, &task). 137 */ 138TASKQUEUE_DECLARE(swi_giant); 139TASKQUEUE_DECLARE(swi); 140 141/* 142 * This queue is serviced by a kernel thread. To enqueue a task, call 143 * taskqueue_enqueue(taskqueue_thread, &task). 144 */ 145TASKQUEUE_DECLARE(thread); 146 147/* 148 * Queue for swi handlers dispatched from fast interrupt handlers. 149 * These are necessarily different from the above because the queue 150 * must be locked with spinlocks since sleep mutex's cannot be used 151 * from a fast interrupt handler context. 152 */ 153TASKQUEUE_DECLARE(fast); 154int taskqueue_enqueue_fast(struct taskqueue *queue, struct task *task); 155struct taskqueue *taskqueue_create_fast(const char *name, int mflags, 156 taskqueue_enqueue_fn enqueue, 157 void *context); 158 159#endif /* !_SYS_TASKQUEUE_H_ */ 160