1 /* $NetBSD: subr_workqueue.c,v 1.2 2005/12/11 12:24:30 christos Exp $ */ 2 3 /*- 4 * Copyright (c)2002, 2005 YAMAMOTO Takashi, 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 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: subr_workqueue.c,v 1.2 2005/12/11 12:24:30 christos Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/kthread.h> 35 #include <sys/malloc.h> 36 #include <sys/proc.h> 37 #include <sys/workqueue.h> 38 39 SIMPLEQ_HEAD(workqhead, work); 40 41 struct workqueue_queue { 42 struct simplelock q_lock; 43 int q_savedipl; 44 struct workqhead q_queue; 45 struct proc *q_worker; 46 }; 47 48 struct workqueue { 49 struct workqueue_queue wq_queue; /* todo: make this per-cpu */ 50 51 void (*wq_func)(struct work *, void *); 52 void *wq_arg; 53 const char *wq_name; 54 int wq_prio; 55 int wq_ipl; 56 }; 57 58 MALLOC_DEFINE(M_WORKQUEUE, "workqueue", "work queue"); 59 60 #define POISON 0xaabbccdd 61 62 static void 63 workqueue_lock(struct workqueue *wq, struct workqueue_queue *q) 64 { 65 int s; 66 67 #if 0 /* notyet */ 68 s = splraiseipl(wq->wq_ipl); 69 #else 70 s = splhigh(); /* XXX */ 71 #endif 72 simple_lock(&q->q_lock); 73 q->q_savedipl = s; 74 } 75 76 static void 77 workqueue_unlock(struct workqueue *wq, struct workqueue_queue *q) 78 { 79 int s = q->q_savedipl; 80 81 simple_unlock(&q->q_lock); 82 splx(s); 83 } 84 85 static void 86 workqueue_runlist(struct workqueue *wq, struct workqhead *list) 87 { 88 struct work *wk; 89 struct work *next; 90 91 /* 92 * note that "list" is not a complete SIMPLEQ. 93 */ 94 95 for (wk = SIMPLEQ_FIRST(list); wk != NULL; wk = next) { 96 next = SIMPLEQ_NEXT(wk, wk_entry); 97 (*wq->wq_func)(wk, wq->wq_arg); 98 } 99 } 100 101 static void 102 workqueue_run(struct workqueue *wq) 103 { 104 struct workqueue_queue *q = &wq->wq_queue; 105 106 while (1 /* CONSTCOND */) { 107 struct workqhead tmp; 108 int error; 109 110 /* 111 * we violate abstraction of SIMPLEQ. 112 */ 113 114 #if defined(DIAGNOSTIC) 115 tmp.sqh_last = (void *)POISON; 116 #endif /* defined(DIAGNOSTIC) */ 117 118 workqueue_lock(wq, q); 119 while (SIMPLEQ_EMPTY(&q->q_queue)) { 120 error = ltsleep(q, wq->wq_prio, wq->wq_name, 0, 121 &q->q_lock); 122 if (error) { 123 panic("%s: %s error=%d", 124 __func__, wq->wq_name, error); 125 } 126 } 127 tmp.sqh_first = q->q_queue.sqh_first; /* XXX */ 128 SIMPLEQ_INIT(&q->q_queue); 129 workqueue_unlock(wq, q); 130 131 workqueue_runlist(wq, &tmp); 132 } 133 } 134 135 static void 136 workqueue_worker(void *arg) 137 { 138 struct workqueue *wq = arg; 139 140 workqueue_run(wq); 141 } 142 143 static void 144 workqueue_init(struct workqueue *wq, const char *name, 145 void (*callback_func)(struct work *, void *), void *callback_arg, 146 int prio, int ipl) 147 { 148 149 wq->wq_ipl = ipl; 150 wq->wq_prio = prio; 151 wq->wq_name = name; 152 wq->wq_func = callback_func; 153 wq->wq_arg = callback_arg; 154 } 155 156 static int 157 workqueue_initqueue(struct workqueue *wq) 158 { 159 struct workqueue_queue *q = &wq->wq_queue; 160 int error; 161 162 simple_lock_init(&q->q_lock); 163 SIMPLEQ_INIT(&q->q_queue); 164 error = kthread_create1(workqueue_worker, wq, &q->q_worker, 165 wq->wq_name); 166 167 return error; 168 } 169 170 /* --- */ 171 172 int 173 workqueue_create(struct workqueue **wqp, const char *name, 174 void (*callback_func)(struct work *, void *), void *callback_arg, 175 int prio, int ipl, int flags) 176 { 177 struct workqueue *wq; 178 int error; 179 180 wq = malloc(sizeof(*wq), M_WORKQUEUE, 0); 181 if (wq == NULL) { 182 return ENOMEM; 183 } 184 185 workqueue_init(wq, name, callback_func, callback_arg, prio, ipl); 186 187 error = workqueue_initqueue(wq); 188 if (error) { 189 free(wq, M_WORKQUEUE); 190 return error; 191 } 192 193 *wqp = wq; 194 return 0; 195 } 196 197 void 198 workqueue_enqueue(struct workqueue *wq, struct work *wk) 199 { 200 struct workqueue_queue *q = &wq->wq_queue; 201 boolean_t wasempty; 202 203 workqueue_lock(wq, q); 204 wasempty = SIMPLEQ_EMPTY(&q->q_queue); 205 SIMPLEQ_INSERT_TAIL(&q->q_queue, wk, wk_entry); 206 workqueue_unlock(wq, q); 207 208 if (wasempty) { 209 wakeup(q); 210 } 211 } 212