taskqueue.h revision 124882
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 124882 2004-01-23 20:44:26Z 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 taskqueue *taskqueue_create(const char *name, int mflags, 51 taskqueue_enqueue_fn enqueue, 52 void *context); 53int taskqueue_enqueue(struct taskqueue *queue, struct task *task); 54struct taskqueue *taskqueue_find(const char *name); 55void taskqueue_free(struct taskqueue *queue); 56void taskqueue_run(struct taskqueue *queue); 57 58/* 59 * Initialise a task structure. 60 */ 61#define TASK_INIT(task, priority, func, context) do { \ 62 (task)->ta_pending = 0; \ 63 (task)->ta_priority = (priority); \ 64 (task)->ta_func = (func); \ 65 (task)->ta_context = (context); \ 66} while (0) 67 68/* 69 * Declare a reference to a taskqueue. 70 */ 71#define TASKQUEUE_DECLARE(name) \ 72extern struct taskqueue *taskqueue_##name 73 74/* 75 * Define and initialise a taskqueue. 76 */ 77#define TASKQUEUE_DEFINE(name, enqueue, context, init) \ 78 \ 79struct taskqueue *taskqueue_##name; \ 80 \ 81static void \ 82taskqueue_define_##name(void *arg) \ 83{ \ 84 taskqueue_##name = \ 85 taskqueue_create(#name, M_NOWAIT, (enqueue), (context)); \ 86 init; \ 87} \ 88 \ 89SYSINIT(taskqueue_##name, SI_SUB_CONFIGURE, SI_ORDER_SECOND, \ 90 taskqueue_define_##name, NULL) \ 91 \ 92struct __hack 93 94/* 95 * These queues are serviced by software interrupt handlers. To enqueue 96 * a task, call taskqueue_enqueue(taskqueue_swi, &task) or 97 * taskqueue_enqueue(taskqueue_swi_giant, &task). 98 */ 99TASKQUEUE_DECLARE(swi_giant); 100TASKQUEUE_DECLARE(swi); 101 102/* 103 * This queue is serviced by a kernel thread. To enqueue a task, call 104 * taskqueue_enqueue(taskqueue_thread, &task). 105 */ 106TASKQUEUE_DECLARE(thread); 107 108/* 109 * Queue for swi handlers dispatched from fast interrupt handlers. 110 * These are necessarily different from the above because the queue 111 * must be locked with spinlocks since sleep mutex's cannot be used 112 * from a fast interrupt handler context. 113 */ 114TASKQUEUE_DECLARE(fast); 115int taskqueue_enqueue_fast(struct taskqueue *queue, struct task *task); 116 117#endif /* !_SYS_TASKQUEUE_H_ */ 118