1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2000 Doug Rabson 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 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/bus.h> 35 #include <sys/cpuset.h> 36 #include <sys/interrupt.h> 37 #include <sys/kernel.h> 38 #include <sys/kthread.h> 39 #include <sys/libkern.h> 40 #include <sys/limits.h> 41 #include <sys/lock.h> 42 #include <sys/malloc.h> 43 #include <sys/mutex.h> 44 #include <sys/proc.h> 45 #include <sys/sched.h> 46 #include <sys/smp.h> 47 #include <sys/taskqueue.h> 48 #include <sys/unistd.h> 49 #include <machine/stdarg.h> 50 51 static MALLOC_DEFINE(M_TASKQUEUE, "taskqueue", "Task Queues"); 52 static void *taskqueue_giant_ih; 53 static void *taskqueue_ih; 54 static void taskqueue_fast_enqueue(void *); 55 static void taskqueue_swi_enqueue(void *); 56 static void taskqueue_swi_giant_enqueue(void *); 57 58 struct taskqueue_busy { 59 struct task *tb_running; 60 TAILQ_ENTRY(taskqueue_busy) tb_link; 61 }; 62 63 struct task * const TB_DRAIN_WAITER = (struct task *)0x1; 64 65 struct taskqueue { 66 STAILQ_HEAD(, task) tq_queue; 67 taskqueue_enqueue_fn tq_enqueue; 68 void *tq_context; 69 char *tq_name; 70 TAILQ_HEAD(, taskqueue_busy) tq_active; 71 struct mtx tq_mutex; 72 struct thread **tq_threads; 73 int tq_tcount; 74 int tq_spin; 75 int tq_flags; 76 int tq_callouts; 77 taskqueue_callback_fn tq_callbacks[TASKQUEUE_NUM_CALLBACKS]; 78 void *tq_cb_contexts[TASKQUEUE_NUM_CALLBACKS]; 79 }; 80 81 #define TQ_FLAGS_ACTIVE (1 << 0) 82 #define TQ_FLAGS_BLOCKED (1 << 1) 83 #define TQ_FLAGS_UNLOCKED_ENQUEUE (1 << 2) 84 85 #define DT_CALLOUT_ARMED (1 << 0) 86 #define DT_DRAIN_IN_PROGRESS (1 << 1) 87 88 #define TQ_LOCK(tq) \ 89 do { \ 90 if ((tq)->tq_spin) \ 91 mtx_lock_spin(&(tq)->tq_mutex); \ 92 else \ 93 mtx_lock(&(tq)->tq_mutex); \ 94 } while (0) 95 #define TQ_ASSERT_LOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_OWNED) 96 97 #define TQ_UNLOCK(tq) \ 98 do { \ 99 if ((tq)->tq_spin) \ 100 mtx_unlock_spin(&(tq)->tq_mutex); \ 101 else \ 102 mtx_unlock(&(tq)->tq_mutex); \ 103 } while (0) 104 #define TQ_ASSERT_UNLOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_NOTOWNED) 105 106 void 107 _timeout_task_init(struct taskqueue *queue, struct timeout_task *timeout_task, 108 int priority, task_fn_t func, void *context) 109 { 110 111 TASK_INIT(&timeout_task->t, priority, func, context); 112 callout_init_mtx(&timeout_task->c, &queue->tq_mutex, 113 CALLOUT_RETURNUNLOCKED); 114 timeout_task->q = queue; 115 timeout_task->f = 0; 116 } 117 118 static __inline int 119 TQ_SLEEP(struct taskqueue *tq, void *p, struct mtx *m, int pri, const char *wm, 120 int t) 121 { 122 if (tq->tq_spin) 123 return (msleep_spin(p, m, wm, t)); 124 return (msleep(p, m, pri, wm, t)); 125 } 126 127 static struct taskqueue * 128 _taskqueue_create(const char *name, int mflags, 129 taskqueue_enqueue_fn enqueue, void *context, 130 int mtxflags, const char *mtxname __unused) 131 { 132 struct taskqueue *queue; 133 char *tq_name; 134 135 tq_name = malloc(TASKQUEUE_NAMELEN, M_TASKQUEUE, mflags | M_ZERO); 136 if (tq_name == NULL) 137 return (NULL); 138 139 queue = malloc(sizeof(struct taskqueue), M_TASKQUEUE, mflags | M_ZERO); 140 if (queue == NULL) { 141 free(tq_name, M_TASKQUEUE); 142 return (NULL); 143 } 144 145 snprintf(tq_name, TASKQUEUE_NAMELEN, "%s", (name) ? name : "taskqueue"); 146 147 STAILQ_INIT(&queue->tq_queue); 148 TAILQ_INIT(&queue->tq_active); 149 queue->tq_enqueue = enqueue; 150 queue->tq_context = context; 151 queue->tq_name = tq_name; 152 queue->tq_spin = (mtxflags & MTX_SPIN) != 0; 153 queue->tq_flags |= TQ_FLAGS_ACTIVE; 154 if (enqueue == taskqueue_fast_enqueue || 155 enqueue == taskqueue_swi_enqueue || 156 enqueue == taskqueue_swi_giant_enqueue || 157 enqueue == taskqueue_thread_enqueue) 158 queue->tq_flags |= TQ_FLAGS_UNLOCKED_ENQUEUE; 159 mtx_init(&queue->tq_mutex, tq_name, NULL, mtxflags); 160 161 return (queue); 162 } 163 164 struct taskqueue * 165 taskqueue_create(const char *name, int mflags, 166 taskqueue_enqueue_fn enqueue, void *context) 167 { 168 169 return _taskqueue_create(name, mflags, enqueue, context, 170 MTX_DEF, name); 171 } 172 173 void 174 taskqueue_set_callback(struct taskqueue *queue, 175 enum taskqueue_callback_type cb_type, taskqueue_callback_fn callback, 176 void *context) 177 { 178 179 KASSERT(((cb_type >= TASKQUEUE_CALLBACK_TYPE_MIN) && 180 (cb_type <= TASKQUEUE_CALLBACK_TYPE_MAX)), 181 ("Callback type %d not valid, must be %d-%d", cb_type, 182 TASKQUEUE_CALLBACK_TYPE_MIN, TASKQUEUE_CALLBACK_TYPE_MAX)); 183 KASSERT((queue->tq_callbacks[cb_type] == NULL), 184 ("Re-initialization of taskqueue callback?")); 185 186 queue->tq_callbacks[cb_type] = callback; 187 queue->tq_cb_contexts[cb_type] = context; 188 } 189 190 /* 191 * Signal a taskqueue thread to terminate. 192 */ 193 static void 194 taskqueue_terminate(struct thread **pp, struct taskqueue *tq) 195 { 196 197 while (tq->tq_tcount > 0 || tq->tq_callouts > 0) { 198 wakeup(tq); 199 TQ_SLEEP(tq, pp, &tq->tq_mutex, PWAIT, "taskqueue_destroy", 0); 200 } 201 } 202 203 void 204 taskqueue_free(struct taskqueue *queue) 205 { 206 207 TQ_LOCK(queue); 208 queue->tq_flags &= ~TQ_FLAGS_ACTIVE; 209 taskqueue_terminate(queue->tq_threads, queue); 210 KASSERT(TAILQ_EMPTY(&queue->tq_active), ("Tasks still running?")); 211 KASSERT(queue->tq_callouts == 0, ("Armed timeout tasks")); 212 mtx_destroy(&queue->tq_mutex); 213 free(queue->tq_threads, M_TASKQUEUE); 214 free(queue->tq_name, M_TASKQUEUE); 215 free(queue, M_TASKQUEUE); 216 } 217 218 static int 219 taskqueue_enqueue_locked(struct taskqueue *queue, struct task *task) 220 { 221 struct task *ins; 222 struct task *prev; 223 224 KASSERT(task->ta_func != NULL, ("enqueueing task with NULL func")); 225 /* 226 * Count multiple enqueues. 227 */ 228 if (task->ta_pending) { 229 if (task->ta_pending < USHRT_MAX) 230 task->ta_pending++; 231 TQ_UNLOCK(queue); 232 return (0); 233 } 234 235 /* 236 * Optimise the case when all tasks have the same priority. 237 */ 238 prev = STAILQ_LAST(&queue->tq_queue, task, ta_link); 239 if (!prev || prev->ta_priority >= task->ta_priority) { 240 STAILQ_INSERT_TAIL(&queue->tq_queue, task, ta_link); 241 } else { 242 prev = NULL; 243 for (ins = STAILQ_FIRST(&queue->tq_queue); ins; 244 prev = ins, ins = STAILQ_NEXT(ins, ta_link)) 245 if (ins->ta_priority < task->ta_priority) 246 break; 247 248 if (prev) 249 STAILQ_INSERT_AFTER(&queue->tq_queue, prev, task, ta_link); 250 else 251 STAILQ_INSERT_HEAD(&queue->tq_queue, task, ta_link); 252 } 253 254 task->ta_pending = 1; 255 if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) != 0) 256 TQ_UNLOCK(queue); 257 if ((queue->tq_flags & TQ_FLAGS_BLOCKED) == 0) 258 queue->tq_enqueue(queue->tq_context); 259 if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) == 0) 260 TQ_UNLOCK(queue); 261 262 /* Return with lock released. */ 263 return (0); 264 } 265 266 int 267 taskqueue_enqueue(struct taskqueue *queue, struct task *task) 268 { 269 int res; 270 271 TQ_LOCK(queue); 272 res = taskqueue_enqueue_locked(queue, task); 273 /* The lock is released inside. */ 274 275 return (res); 276 } 277 278 static void 279 taskqueue_timeout_func(void *arg) 280 { 281 struct taskqueue *queue; 282 struct timeout_task *timeout_task; 283 284 timeout_task = arg; 285 queue = timeout_task->q; 286 KASSERT((timeout_task->f & DT_CALLOUT_ARMED) != 0, ("Stray timeout")); 287 timeout_task->f &= ~DT_CALLOUT_ARMED; 288 queue->tq_callouts--; 289 taskqueue_enqueue_locked(timeout_task->q, &timeout_task->t); 290 /* The lock is released inside. */ 291 } 292 293 int 294 taskqueue_enqueue_timeout_sbt(struct taskqueue *queue, 295 struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr, int flags) 296 { 297 int res; 298 299 TQ_LOCK(queue); 300 KASSERT(timeout_task->q == NULL || timeout_task->q == queue, 301 ("Migrated queue")); 302 KASSERT(!queue->tq_spin, ("Timeout for spin-queue")); 303 timeout_task->q = queue; 304 res = timeout_task->t.ta_pending; 305 if (timeout_task->f & DT_DRAIN_IN_PROGRESS) { 306 /* Do nothing */ 307 TQ_UNLOCK(queue); 308 res = -1; 309 } else if (sbt == 0) { 310 taskqueue_enqueue_locked(queue, &timeout_task->t); 311 /* The lock is released inside. */ 312 } else { 313 if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) { 314 res++; 315 } else { 316 queue->tq_callouts++; 317 timeout_task->f |= DT_CALLOUT_ARMED; 318 if (sbt < 0) 319 sbt = -sbt; /* Ignore overflow. */ 320 } 321 if (sbt > 0) { 322 callout_reset_sbt(&timeout_task->c, sbt, pr, 323 taskqueue_timeout_func, timeout_task, flags); 324 } 325 TQ_UNLOCK(queue); 326 } 327 return (res); 328 } 329 330 int 331 taskqueue_enqueue_timeout(struct taskqueue *queue, 332 struct timeout_task *ttask, int ticks) 333 { 334 335 return (taskqueue_enqueue_timeout_sbt(queue, ttask, ticks * tick_sbt, 336 0, 0)); 337 } 338 339 static void 340 taskqueue_task_nop_fn(void *context, int pending) 341 { 342 } 343 344 /* 345 * Block until all currently queued tasks in this taskqueue 346 * have begun execution. Tasks queued during execution of 347 * this function are ignored. 348 */ 349 static void 350 taskqueue_drain_tq_queue(struct taskqueue *queue) 351 { 352 struct task t_barrier; 353 354 if (STAILQ_EMPTY(&queue->tq_queue)) 355 return; 356 357 /* 358 * Enqueue our barrier after all current tasks, but with 359 * the highest priority so that newly queued tasks cannot 360 * pass it. Because of the high priority, we can not use 361 * taskqueue_enqueue_locked directly (which drops the lock 362 * anyway) so just insert it at tail while we have the 363 * queue lock. 364 */ 365 TASK_INIT(&t_barrier, USHRT_MAX, taskqueue_task_nop_fn, &t_barrier); 366 STAILQ_INSERT_TAIL(&queue->tq_queue, &t_barrier, ta_link); 367 t_barrier.ta_pending = 1; 368 369 /* 370 * Once the barrier has executed, all previously queued tasks 371 * have completed or are currently executing. 372 */ 373 while (t_barrier.ta_pending != 0) 374 TQ_SLEEP(queue, &t_barrier, &queue->tq_mutex, PWAIT, "-", 0); 375 } 376 377 /* 378 * Block until all currently executing tasks for this taskqueue 379 * complete. Tasks that begin execution during the execution 380 * of this function are ignored. 381 */ 382 static void 383 taskqueue_drain_tq_active(struct taskqueue *queue) 384 { 385 struct taskqueue_busy tb_marker, *tb_first; 386 387 if (TAILQ_EMPTY(&queue->tq_active)) 388 return; 389 390 /* Block taskq_terminate().*/ 391 queue->tq_callouts++; 392 393 /* 394 * Wait for all currently executing taskqueue threads 395 * to go idle. 396 */ 397 tb_marker.tb_running = TB_DRAIN_WAITER; 398 TAILQ_INSERT_TAIL(&queue->tq_active, &tb_marker, tb_link); 399 while (TAILQ_FIRST(&queue->tq_active) != &tb_marker) 400 TQ_SLEEP(queue, &tb_marker, &queue->tq_mutex, PWAIT, "-", 0); 401 TAILQ_REMOVE(&queue->tq_active, &tb_marker, tb_link); 402 403 /* 404 * Wakeup any other drain waiter that happened to queue up 405 * without any intervening active thread. 406 */ 407 tb_first = TAILQ_FIRST(&queue->tq_active); 408 if (tb_first != NULL && tb_first->tb_running == TB_DRAIN_WAITER) 409 wakeup(tb_first); 410 411 /* Release taskqueue_terminate(). */ 412 queue->tq_callouts--; 413 if ((queue->tq_flags & TQ_FLAGS_ACTIVE) == 0) 414 wakeup_one(queue->tq_threads); 415 } 416 417 void 418 taskqueue_block(struct taskqueue *queue) 419 { 420 421 TQ_LOCK(queue); 422 queue->tq_flags |= TQ_FLAGS_BLOCKED; 423 TQ_UNLOCK(queue); 424 } 425 426 void 427 taskqueue_unblock(struct taskqueue *queue) 428 { 429 430 TQ_LOCK(queue); 431 queue->tq_flags &= ~TQ_FLAGS_BLOCKED; 432 if (!STAILQ_EMPTY(&queue->tq_queue)) 433 queue->tq_enqueue(queue->tq_context); 434 TQ_UNLOCK(queue); 435 } 436 437 static void 438 taskqueue_run_locked(struct taskqueue *queue) 439 { 440 struct taskqueue_busy tb; 441 struct taskqueue_busy *tb_first; 442 struct task *task; 443 int pending; 444 445 KASSERT(queue != NULL, ("tq is NULL")); 446 TQ_ASSERT_LOCKED(queue); 447 tb.tb_running = NULL; 448 449 while (STAILQ_FIRST(&queue->tq_queue)) { 450 TAILQ_INSERT_TAIL(&queue->tq_active, &tb, tb_link); 451 452 /* 453 * Carefully remove the first task from the queue and 454 * zero its pending count. 455 */ 456 task = STAILQ_FIRST(&queue->tq_queue); 457 KASSERT(task != NULL, ("task is NULL")); 458 STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link); 459 pending = task->ta_pending; 460 task->ta_pending = 0; 461 tb.tb_running = task; 462 TQ_UNLOCK(queue); 463 464 KASSERT(task->ta_func != NULL, ("task->ta_func is NULL")); 465 task->ta_func(task->ta_context, pending); 466 467 TQ_LOCK(queue); 468 tb.tb_running = NULL; 469 wakeup(task); 470 471 TAILQ_REMOVE(&queue->tq_active, &tb, tb_link); 472 tb_first = TAILQ_FIRST(&queue->tq_active); 473 if (tb_first != NULL && 474 tb_first->tb_running == TB_DRAIN_WAITER) 475 wakeup(tb_first); 476 } 477 } 478 479 void 480 taskqueue_run(struct taskqueue *queue) 481 { 482 483 TQ_LOCK(queue); 484 taskqueue_run_locked(queue); 485 TQ_UNLOCK(queue); 486 } 487 488 static int 489 task_is_running(struct taskqueue *queue, struct task *task) 490 { 491 struct taskqueue_busy *tb; 492 493 TQ_ASSERT_LOCKED(queue); 494 TAILQ_FOREACH(tb, &queue->tq_active, tb_link) { 495 if (tb->tb_running == task) 496 return (1); 497 } 498 return (0); 499 } 500 501 /* 502 * Only use this function in single threaded contexts. It returns 503 * non-zero if the given task is either pending or running. Else the 504 * task is idle and can be queued again or freed. 505 */ 506 int 507 taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task) 508 { 509 int retval; 510 511 TQ_LOCK(queue); 512 retval = task->ta_pending > 0 || task_is_running(queue, task); 513 TQ_UNLOCK(queue); 514 515 return (retval); 516 } 517 518 static int 519 taskqueue_cancel_locked(struct taskqueue *queue, struct task *task, 520 u_int *pendp) 521 { 522 523 if (task->ta_pending > 0) 524 STAILQ_REMOVE(&queue->tq_queue, task, task, ta_link); 525 if (pendp != NULL) 526 *pendp = task->ta_pending; 527 task->ta_pending = 0; 528 return (task_is_running(queue, task) ? EBUSY : 0); 529 } 530 531 int 532 taskqueue_cancel(struct taskqueue *queue, struct task *task, u_int *pendp) 533 { 534 int error; 535 536 TQ_LOCK(queue); 537 error = taskqueue_cancel_locked(queue, task, pendp); 538 TQ_UNLOCK(queue); 539 540 return (error); 541 } 542 543 int 544 taskqueue_cancel_timeout(struct taskqueue *queue, 545 struct timeout_task *timeout_task, u_int *pendp) 546 { 547 u_int pending, pending1; 548 int error; 549 550 TQ_LOCK(queue); 551 pending = !!(callout_stop(&timeout_task->c) > 0); 552 error = taskqueue_cancel_locked(queue, &timeout_task->t, &pending1); 553 if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) { 554 timeout_task->f &= ~DT_CALLOUT_ARMED; 555 queue->tq_callouts--; 556 } 557 TQ_UNLOCK(queue); 558 559 if (pendp != NULL) 560 *pendp = pending + pending1; 561 return (error); 562 } 563 564 void 565 taskqueue_drain(struct taskqueue *queue, struct task *task) 566 { 567 568 if (!queue->tq_spin) 569 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 570 571 TQ_LOCK(queue); 572 while (task->ta_pending != 0 || task_is_running(queue, task)) 573 TQ_SLEEP(queue, task, &queue->tq_mutex, PWAIT, "-", 0); 574 TQ_UNLOCK(queue); 575 } 576 577 void 578 taskqueue_drain_all(struct taskqueue *queue) 579 { 580 581 if (!queue->tq_spin) 582 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 583 584 TQ_LOCK(queue); 585 taskqueue_drain_tq_queue(queue); 586 taskqueue_drain_tq_active(queue); 587 TQ_UNLOCK(queue); 588 } 589 590 void 591 taskqueue_drain_timeout(struct taskqueue *queue, 592 struct timeout_task *timeout_task) 593 { 594 595 /* 596 * Set flag to prevent timer from re-starting during drain: 597 */ 598 TQ_LOCK(queue); 599 KASSERT((timeout_task->f & DT_DRAIN_IN_PROGRESS) == 0, 600 ("Drain already in progress")); 601 timeout_task->f |= DT_DRAIN_IN_PROGRESS; 602 TQ_UNLOCK(queue); 603 604 callout_drain(&timeout_task->c); 605 taskqueue_drain(queue, &timeout_task->t); 606 607 /* 608 * Clear flag to allow timer to re-start: 609 */ 610 TQ_LOCK(queue); 611 timeout_task->f &= ~DT_DRAIN_IN_PROGRESS; 612 TQ_UNLOCK(queue); 613 } 614 615 static void 616 taskqueue_swi_enqueue(void *context) 617 { 618 swi_sched(taskqueue_ih, 0); 619 } 620 621 static void 622 taskqueue_swi_run(void *dummy) 623 { 624 taskqueue_run(taskqueue_swi); 625 } 626 627 static void 628 taskqueue_swi_giant_enqueue(void *context) 629 { 630 swi_sched(taskqueue_giant_ih, 0); 631 } 632 633 static void 634 taskqueue_swi_giant_run(void *dummy) 635 { 636 taskqueue_run(taskqueue_swi_giant); 637 } 638 639 static int 640 _taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 641 cpuset_t *mask, const char *name, va_list ap) 642 { 643 char ktname[MAXCOMLEN + 1]; 644 struct thread *td; 645 struct taskqueue *tq; 646 int i, error; 647 648 if (count <= 0) 649 return (EINVAL); 650 651 vsnprintf(ktname, sizeof(ktname), name, ap); 652 tq = *tqp; 653 654 tq->tq_threads = malloc(sizeof(struct thread *) * count, M_TASKQUEUE, 655 M_NOWAIT | M_ZERO); 656 if (tq->tq_threads == NULL) { 657 printf("%s: no memory for %s threads\n", __func__, ktname); 658 return (ENOMEM); 659 } 660 661 for (i = 0; i < count; i++) { 662 if (count == 1) 663 error = kthread_add(taskqueue_thread_loop, tqp, NULL, 664 &tq->tq_threads[i], RFSTOPPED, 0, "%s", ktname); 665 else 666 error = kthread_add(taskqueue_thread_loop, tqp, NULL, 667 &tq->tq_threads[i], RFSTOPPED, 0, 668 "%s_%d", ktname, i); 669 if (error) { 670 /* should be ok to continue, taskqueue_free will dtrt */ 671 printf("%s: kthread_add(%s): error %d", __func__, 672 ktname, error); 673 tq->tq_threads[i] = NULL; /* paranoid */ 674 } else 675 tq->tq_tcount++; 676 } 677 if (tq->tq_tcount == 0) { 678 free(tq->tq_threads, M_TASKQUEUE); 679 tq->tq_threads = NULL; 680 return (ENOMEM); 681 } 682 for (i = 0; i < count; i++) { 683 if (tq->tq_threads[i] == NULL) 684 continue; 685 td = tq->tq_threads[i]; 686 if (mask) { 687 error = cpuset_setthread(td->td_tid, mask); 688 /* 689 * Failing to pin is rarely an actual fatal error; 690 * it'll just affect performance. 691 */ 692 if (error) 693 printf("%s: curthread=%llu: can't pin; " 694 "error=%d\n", 695 __func__, 696 (unsigned long long) td->td_tid, 697 error); 698 } 699 thread_lock(td); 700 sched_prio(td, pri); 701 sched_add(td, SRQ_BORING); 702 thread_unlock(td); 703 } 704 705 return (0); 706 } 707 708 int 709 taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 710 const char *name, ...) 711 { 712 va_list ap; 713 int error; 714 715 va_start(ap, name); 716 error = _taskqueue_start_threads(tqp, count, pri, NULL, name, ap); 717 va_end(ap); 718 return (error); 719 } 720 721 int 722 taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count, int pri, 723 cpuset_t *mask, const char *name, ...) 724 { 725 va_list ap; 726 int error; 727 728 va_start(ap, name); 729 error = _taskqueue_start_threads(tqp, count, pri, mask, name, ap); 730 va_end(ap); 731 return (error); 732 } 733 734 static inline void 735 taskqueue_run_callback(struct taskqueue *tq, 736 enum taskqueue_callback_type cb_type) 737 { 738 taskqueue_callback_fn tq_callback; 739 740 TQ_ASSERT_UNLOCKED(tq); 741 tq_callback = tq->tq_callbacks[cb_type]; 742 if (tq_callback != NULL) 743 tq_callback(tq->tq_cb_contexts[cb_type]); 744 } 745 746 void 747 taskqueue_thread_loop(void *arg) 748 { 749 struct taskqueue **tqp, *tq; 750 751 tqp = arg; 752 tq = *tqp; 753 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_INIT); 754 TQ_LOCK(tq); 755 while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) { 756 /* XXX ? */ 757 taskqueue_run_locked(tq); 758 /* 759 * Because taskqueue_run() can drop tq_mutex, we need to 760 * check if the TQ_FLAGS_ACTIVE flag wasn't removed in the 761 * meantime, which means we missed a wakeup. 762 */ 763 if ((tq->tq_flags & TQ_FLAGS_ACTIVE) == 0) 764 break; 765 TQ_SLEEP(tq, tq, &tq->tq_mutex, 0, "-", 0); 766 } 767 taskqueue_run_locked(tq); 768 /* 769 * This thread is on its way out, so just drop the lock temporarily 770 * in order to call the shutdown callback. This allows the callback 771 * to look at the taskqueue, even just before it dies. 772 */ 773 TQ_UNLOCK(tq); 774 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN); 775 TQ_LOCK(tq); 776 777 /* rendezvous with thread that asked us to terminate */ 778 tq->tq_tcount--; 779 wakeup_one(tq->tq_threads); 780 TQ_UNLOCK(tq); 781 kthread_exit(); 782 } 783 784 void 785 taskqueue_thread_enqueue(void *context) 786 { 787 struct taskqueue **tqp, *tq; 788 789 tqp = context; 790 tq = *tqp; 791 wakeup_one(tq); 792 } 793 794 TASKQUEUE_DEFINE(swi, taskqueue_swi_enqueue, NULL, 795 swi_add(NULL, "task queue", taskqueue_swi_run, NULL, SWI_TQ, 796 INTR_MPSAFE, &taskqueue_ih)); 797 798 TASKQUEUE_DEFINE(swi_giant, taskqueue_swi_giant_enqueue, NULL, 799 swi_add(NULL, "Giant taskq", taskqueue_swi_giant_run, 800 NULL, SWI_TQ_GIANT, 0, &taskqueue_giant_ih)); 801 802 TASKQUEUE_DEFINE_THREAD(thread); 803 804 struct taskqueue * 805 taskqueue_create_fast(const char *name, int mflags, 806 taskqueue_enqueue_fn enqueue, void *context) 807 { 808 return _taskqueue_create(name, mflags, enqueue, context, 809 MTX_SPIN, "fast_taskqueue"); 810 } 811 812 static void *taskqueue_fast_ih; 813 814 static void 815 taskqueue_fast_enqueue(void *context) 816 { 817 swi_sched(taskqueue_fast_ih, 0); 818 } 819 820 static void 821 taskqueue_fast_run(void *dummy) 822 { 823 taskqueue_run(taskqueue_fast); 824 } 825 826 TASKQUEUE_FAST_DEFINE(fast, taskqueue_fast_enqueue, NULL, 827 swi_add(NULL, "fast taskq", taskqueue_fast_run, NULL, 828 SWI_TQ_FAST, INTR_MPSAFE, &taskqueue_fast_ih)); 829 830 int 831 taskqueue_member(struct taskqueue *queue, struct thread *td) 832 { 833 int i, j, ret = 0; 834 835 for (i = 0, j = 0; ; i++) { 836 if (queue->tq_threads[i] == NULL) 837 continue; 838 if (queue->tq_threads[i] == td) { 839 ret = 1; 840 break; 841 } 842 if (++j >= queue->tq_tcount) 843 break; 844 } 845 return (ret); 846 } 847