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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/systm.h>
33 #include <sys/interrupt.h>
34 #include <sys/kernel.h>
35 #include <sys/kthread.h>
37 #include <sys/malloc.h>
38 #include <sys/mutex.h>
40 #include <sys/sched.h>
41 #include <sys/taskqueue.h>
42 #include <sys/unistd.h>
43 #include <machine/stdarg.h>
45 static MALLOC_DEFINE(M_TASKQUEUE, "taskqueue", "Task Queues");
46 static void *taskqueue_giant_ih;
47 static void *taskqueue_ih;
48 static STAILQ_HEAD(taskqueue_list, taskqueue) taskqueue_queues;
49 static struct mtx taskqueue_queues_mutex;
52 STAILQ_ENTRY(taskqueue) tq_link;
53 STAILQ_HEAD(, task) tq_queue;
55 taskqueue_enqueue_fn tq_enqueue;
57 struct task *tq_running;
59 struct proc **tq_pproc;
65 #define TQ_FLAGS_ACTIVE (1 << 0)
68 TQ_LOCK(struct taskqueue *tq)
71 mtx_lock_spin(&tq->tq_mutex);
73 mtx_lock(&tq->tq_mutex);
77 TQ_UNLOCK(struct taskqueue *tq)
80 mtx_unlock_spin(&tq->tq_mutex);
82 mtx_unlock(&tq->tq_mutex);
85 static void init_taskqueue_list(void *data);
88 TQ_SLEEP(struct taskqueue *tq, void *p, struct mtx *m, int pri, const char *wm,
92 return (msleep_spin(p, m, wm, t));
93 return (msleep(p, m, pri, wm, t));
97 init_taskqueue_list(void *data __unused)
100 mtx_init(&taskqueue_queues_mutex, "taskqueue list", NULL, MTX_DEF);
101 STAILQ_INIT(&taskqueue_queues);
103 SYSINIT(taskqueue_list, SI_SUB_INTRINSIC, SI_ORDER_ANY, init_taskqueue_list,
106 static struct taskqueue *
107 _taskqueue_create(const char *name, int mflags,
108 taskqueue_enqueue_fn enqueue, void *context,
109 int mtxflags, const char *mtxname)
111 struct taskqueue *queue;
113 queue = malloc(sizeof(struct taskqueue), M_TASKQUEUE, mflags | M_ZERO);
117 STAILQ_INIT(&queue->tq_queue);
118 queue->tq_name = name;
119 queue->tq_enqueue = enqueue;
120 queue->tq_context = context;
121 queue->tq_spin = (mtxflags & MTX_SPIN) != 0;
122 queue->tq_flags |= TQ_FLAGS_ACTIVE;
123 mtx_init(&queue->tq_mutex, mtxname, NULL, mtxflags);
125 mtx_lock(&taskqueue_queues_mutex);
126 STAILQ_INSERT_TAIL(&taskqueue_queues, queue, tq_link);
127 mtx_unlock(&taskqueue_queues_mutex);
133 taskqueue_create(const char *name, int mflags,
134 taskqueue_enqueue_fn enqueue, void *context)
136 return _taskqueue_create(name, mflags, enqueue, context,
137 MTX_DEF, "taskqueue");
141 * Signal a taskqueue thread to terminate.
144 taskqueue_terminate(struct proc **pp, struct taskqueue *tq)
147 while (tq->tq_pcount > 0) {
149 TQ_SLEEP(tq, pp, &tq->tq_mutex, PWAIT, "taskqueue_destroy", 0);
154 taskqueue_free(struct taskqueue *queue)
157 mtx_lock(&taskqueue_queues_mutex);
158 STAILQ_REMOVE(&taskqueue_queues, queue, taskqueue, tq_link);
159 mtx_unlock(&taskqueue_queues_mutex);
162 queue->tq_flags &= ~TQ_FLAGS_ACTIVE;
163 taskqueue_run(queue);
164 taskqueue_terminate(queue->tq_pproc, queue);
165 mtx_destroy(&queue->tq_mutex);
166 free(queue->tq_pproc, M_TASKQUEUE);
167 free(queue, M_TASKQUEUE);
171 * Returns with the taskqueue locked.
174 taskqueue_find(const char *name)
176 struct taskqueue *queue;
178 mtx_lock(&taskqueue_queues_mutex);
179 STAILQ_FOREACH(queue, &taskqueue_queues, tq_link) {
180 if (strcmp(queue->tq_name, name) == 0) {
182 mtx_unlock(&taskqueue_queues_mutex);
186 mtx_unlock(&taskqueue_queues_mutex);
191 taskqueue_enqueue(struct taskqueue *queue, struct task *task)
199 * Count multiple enqueues.
201 if (task->ta_pending) {
208 * Optimise the case when all tasks have the same priority.
210 prev = STAILQ_LAST(&queue->tq_queue, task, ta_link);
211 if (!prev || prev->ta_priority >= task->ta_priority) {
212 STAILQ_INSERT_TAIL(&queue->tq_queue, task, ta_link);
215 for (ins = STAILQ_FIRST(&queue->tq_queue); ins;
216 prev = ins, ins = STAILQ_NEXT(ins, ta_link))
217 if (ins->ta_priority < task->ta_priority)
221 STAILQ_INSERT_AFTER(&queue->tq_queue, prev, task, ta_link);
223 STAILQ_INSERT_HEAD(&queue->tq_queue, task, ta_link);
226 task->ta_pending = 1;
227 queue->tq_enqueue(queue->tq_context);
235 taskqueue_run(struct taskqueue *queue)
240 owned = mtx_owned(&queue->tq_mutex);
243 while (STAILQ_FIRST(&queue->tq_queue)) {
245 * Carefully remove the first task from the queue and
246 * zero its pending count.
248 task = STAILQ_FIRST(&queue->tq_queue);
249 STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link);
250 pending = task->ta_pending;
251 task->ta_pending = 0;
252 queue->tq_running = task;
255 task->ta_func(task->ta_context, pending);
258 queue->tq_running = NULL;
263 * For compatibility, unlock on return if the queue was not locked
264 * on entry, although this opens a race window.
271 taskqueue_drain(struct taskqueue *queue, struct task *task)
273 if (queue->tq_spin) { /* XXX */
274 mtx_lock_spin(&queue->tq_mutex);
275 while (task->ta_pending != 0 || task == queue->tq_running)
276 msleep_spin(task, &queue->tq_mutex, "-", 0);
277 mtx_unlock_spin(&queue->tq_mutex);
279 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__);
281 mtx_lock(&queue->tq_mutex);
282 while (task->ta_pending != 0 || task == queue->tq_running)
283 msleep(task, &queue->tq_mutex, PWAIT, "-", 0);
284 mtx_unlock(&queue->tq_mutex);
289 taskqueue_swi_enqueue(void *context)
291 swi_sched(taskqueue_ih, 0);
295 taskqueue_swi_run(void *dummy)
297 taskqueue_run(taskqueue_swi);
301 taskqueue_swi_giant_enqueue(void *context)
303 swi_sched(taskqueue_giant_ih, 0);
307 taskqueue_swi_giant_run(void *dummy)
309 taskqueue_run(taskqueue_swi_giant);
313 taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
314 const char *name, ...)
317 struct taskqueue *tq;
319 char ktname[MAXCOMLEN];
327 vsnprintf(ktname, MAXCOMLEN, name, ap);
330 tq->tq_pproc = malloc(sizeof(struct proc *) * count, M_TASKQUEUE,
332 if (tq->tq_pproc == NULL) {
333 printf("%s: no memory for %s threads\n", __func__, ktname);
337 for (i = 0; i < count; i++) {
339 error = kthread_create(taskqueue_thread_loop, tqp,
340 &tq->tq_pproc[i], RFSTOPPED, 0, ktname);
342 error = kthread_create(taskqueue_thread_loop, tqp,
343 &tq->tq_pproc[i], RFSTOPPED, 0, "%s_%d", ktname, i);
345 /* should be ok to continue, taskqueue_free will dtrt */
346 printf("%s: kthread_create(%s): error %d",
347 __func__, ktname, error);
348 tq->tq_pproc[i] = NULL; /* paranoid */
352 mtx_lock_spin(&sched_lock);
353 for (i = 0; i < count; i++) {
354 if (tq->tq_pproc[i] == NULL)
356 td = FIRST_THREAD_IN_PROC(tq->tq_pproc[i]);
358 sched_add(td, SRQ_BORING);
360 mtx_unlock_spin(&sched_lock);
366 taskqueue_thread_loop(void *arg)
368 struct taskqueue **tqp, *tq;
375 TQ_SLEEP(tq, tq, &tq->tq_mutex, 0, "-", 0);
376 } while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0);
378 /* rendezvous with thread that asked us to terminate */
380 wakeup_one(tq->tq_pproc);
386 taskqueue_thread_enqueue(void *context)
388 struct taskqueue **tqp, *tq;
393 mtx_assert(&tq->tq_mutex, MA_OWNED);
397 TASKQUEUE_DEFINE(swi, taskqueue_swi_enqueue, 0,
398 swi_add(NULL, "task queue", taskqueue_swi_run, NULL, SWI_TQ,
399 INTR_MPSAFE, &taskqueue_ih));
401 TASKQUEUE_DEFINE(swi_giant, taskqueue_swi_giant_enqueue, 0,
402 swi_add(NULL, "Giant taskq", taskqueue_swi_giant_run,
403 NULL, SWI_TQ_GIANT, 0, &taskqueue_giant_ih));
405 TASKQUEUE_DEFINE_THREAD(thread);
408 taskqueue_create_fast(const char *name, int mflags,
409 taskqueue_enqueue_fn enqueue, void *context)
411 return _taskqueue_create(name, mflags, enqueue, context,
412 MTX_SPIN, "fast_taskqueue");
415 /* NB: for backwards compatibility */
417 taskqueue_enqueue_fast(struct taskqueue *queue, struct task *task)
419 return taskqueue_enqueue(queue, task);
422 static void *taskqueue_fast_ih;
425 taskqueue_fast_enqueue(void *context)
427 swi_sched(taskqueue_fast_ih, 0);
431 taskqueue_fast_run(void *dummy)
433 taskqueue_run(taskqueue_fast);
436 TASKQUEUE_FAST_DEFINE(fast, taskqueue_fast_enqueue, 0,
437 swi_add(NULL, "Fast task queue", taskqueue_fast_run, NULL,
438 SWI_TQ_FAST, INTR_MPSAFE, &taskqueue_fast_ih));