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 u_int tb_seq; 61 LIST_ENTRY(taskqueue_busy) tb_link; 62 }; 63 64 struct taskqueue { 65 STAILQ_HEAD(, task) tq_queue; 66 LIST_HEAD(, taskqueue_busy) tq_active; 67 struct task *tq_hint; 68 u_int tq_seq; 69 int tq_callouts; 70 struct mtx_padalign tq_mutex; 71 taskqueue_enqueue_fn tq_enqueue; 72 void *tq_context; 73 char *tq_name; 74 struct thread **tq_threads; 75 int tq_tcount; 76 int tq_spin; 77 int tq_flags; 78 taskqueue_callback_fn tq_callbacks[TASKQUEUE_NUM_CALLBACKS]; 79 void *tq_cb_contexts[TASKQUEUE_NUM_CALLBACKS]; 80 }; 81 82 #define TQ_FLAGS_ACTIVE (1 << 0) 83 #define TQ_FLAGS_BLOCKED (1 << 1) 84 #define TQ_FLAGS_UNLOCKED_ENQUEUE (1 << 2) 85 86 #define DT_CALLOUT_ARMED (1 << 0) 87 #define DT_DRAIN_IN_PROGRESS (1 << 1) 88 89 #define TQ_LOCK(tq) \ 90 do { \ 91 if ((tq)->tq_spin) \ 92 mtx_lock_spin(&(tq)->tq_mutex); \ 93 else \ 94 mtx_lock(&(tq)->tq_mutex); \ 95 } while (0) 96 #define TQ_ASSERT_LOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_OWNED) 97 98 #define TQ_UNLOCK(tq) \ 99 do { \ 100 if ((tq)->tq_spin) \ 101 mtx_unlock_spin(&(tq)->tq_mutex); \ 102 else \ 103 mtx_unlock(&(tq)->tq_mutex); \ 104 } while (0) 105 #define TQ_ASSERT_UNLOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_NOTOWNED) 106 107 void 108 _timeout_task_init(struct taskqueue *queue, struct timeout_task *timeout_task, 109 int priority, task_fn_t func, void *context) 110 { 111 112 TASK_INIT(&timeout_task->t, priority, func, context); 113 callout_init_mtx(&timeout_task->c, &queue->tq_mutex, 114 CALLOUT_RETURNUNLOCKED); 115 timeout_task->q = queue; 116 timeout_task->f = 0; 117 } 118 119 static __inline int 120 TQ_SLEEP(struct taskqueue *tq, void *p, const char *wm) 121 { 122 if (tq->tq_spin) 123 return (msleep_spin(p, (struct mtx *)&tq->tq_mutex, wm, 0)); 124 return (msleep(p, &tq->tq_mutex, 0, wm, 0)); 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 LIST_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_destroy"); 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(LIST_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 cases when all tasks use small set of priorities. 237 * In case of only one priority we always insert at the end. 238 * In case of two tq_hint typically gives the insertion point. 239 * In case of more then two tq_hint should halve the search. 240 */ 241 prev = STAILQ_LAST(&queue->tq_queue, task, ta_link); 242 if (!prev || prev->ta_priority >= task->ta_priority) { 243 STAILQ_INSERT_TAIL(&queue->tq_queue, task, ta_link); 244 } else { 245 prev = queue->tq_hint; 246 if (prev && prev->ta_priority >= task->ta_priority) { 247 ins = STAILQ_NEXT(prev, ta_link); 248 } else { 249 prev = NULL; 250 ins = STAILQ_FIRST(&queue->tq_queue); 251 } 252 for (; ins; prev = ins, ins = STAILQ_NEXT(ins, ta_link)) 253 if (ins->ta_priority < task->ta_priority) 254 break; 255 256 if (prev) { 257 STAILQ_INSERT_AFTER(&queue->tq_queue, prev, task, ta_link); 258 queue->tq_hint = task; 259 } else 260 STAILQ_INSERT_HEAD(&queue->tq_queue, task, ta_link); 261 } 262 263 task->ta_pending = 1; 264 if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) != 0) 265 TQ_UNLOCK(queue); 266 if ((queue->tq_flags & TQ_FLAGS_BLOCKED) == 0) 267 queue->tq_enqueue(queue->tq_context); 268 if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) == 0) 269 TQ_UNLOCK(queue); 270 271 /* Return with lock released. */ 272 return (0); 273 } 274 275 int 276 taskqueue_enqueue(struct taskqueue *queue, struct task *task) 277 { 278 int res; 279 280 TQ_LOCK(queue); 281 res = taskqueue_enqueue_locked(queue, task); 282 /* The lock is released inside. */ 283 284 return (res); 285 } 286 287 static void 288 taskqueue_timeout_func(void *arg) 289 { 290 struct taskqueue *queue; 291 struct timeout_task *timeout_task; 292 293 timeout_task = arg; 294 queue = timeout_task->q; 295 KASSERT((timeout_task->f & DT_CALLOUT_ARMED) != 0, ("Stray timeout")); 296 timeout_task->f &= ~DT_CALLOUT_ARMED; 297 queue->tq_callouts--; 298 taskqueue_enqueue_locked(timeout_task->q, &timeout_task->t); 299 /* The lock is released inside. */ 300 } 301 302 int 303 taskqueue_enqueue_timeout_sbt(struct taskqueue *queue, 304 struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr, int flags) 305 { 306 int res; 307 308 TQ_LOCK(queue); 309 KASSERT(timeout_task->q == NULL || timeout_task->q == queue, 310 ("Migrated queue")); 311 KASSERT(!queue->tq_spin, ("Timeout for spin-queue")); 312 timeout_task->q = queue; 313 res = timeout_task->t.ta_pending; 314 if (timeout_task->f & DT_DRAIN_IN_PROGRESS) { 315 /* Do nothing */ 316 TQ_UNLOCK(queue); 317 res = -1; 318 } else if (sbt == 0) { 319 taskqueue_enqueue_locked(queue, &timeout_task->t); 320 /* The lock is released inside. */ 321 } else { 322 if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) { 323 res++; 324 } else { 325 queue->tq_callouts++; 326 timeout_task->f |= DT_CALLOUT_ARMED; 327 if (sbt < 0) 328 sbt = -sbt; /* Ignore overflow. */ 329 } 330 if (sbt > 0) { 331 callout_reset_sbt(&timeout_task->c, sbt, pr, 332 taskqueue_timeout_func, timeout_task, flags); 333 } 334 TQ_UNLOCK(queue); 335 } 336 return (res); 337 } 338 339 int 340 taskqueue_enqueue_timeout(struct taskqueue *queue, 341 struct timeout_task *ttask, int ticks) 342 { 343 344 return (taskqueue_enqueue_timeout_sbt(queue, ttask, ticks * tick_sbt, 345 0, 0)); 346 } 347 348 static void 349 taskqueue_task_nop_fn(void *context, int pending) 350 { 351 } 352 353 /* 354 * Block until all currently queued tasks in this taskqueue 355 * have begun execution. Tasks queued during execution of 356 * this function are ignored. 357 */ 358 static int 359 taskqueue_drain_tq_queue(struct taskqueue *queue) 360 { 361 struct task t_barrier; 362 363 if (STAILQ_EMPTY(&queue->tq_queue)) 364 return (0); 365 366 /* 367 * Enqueue our barrier after all current tasks, but with 368 * the highest priority so that newly queued tasks cannot 369 * pass it. Because of the high priority, we can not use 370 * taskqueue_enqueue_locked directly (which drops the lock 371 * anyway) so just insert it at tail while we have the 372 * queue lock. 373 */ 374 TASK_INIT(&t_barrier, USHRT_MAX, taskqueue_task_nop_fn, &t_barrier); 375 STAILQ_INSERT_TAIL(&queue->tq_queue, &t_barrier, ta_link); 376 queue->tq_hint = &t_barrier; 377 t_barrier.ta_pending = 1; 378 379 /* 380 * Once the barrier has executed, all previously queued tasks 381 * have completed or are currently executing. 382 */ 383 while (t_barrier.ta_pending != 0) 384 TQ_SLEEP(queue, &t_barrier, "tq_qdrain"); 385 return (1); 386 } 387 388 /* 389 * Block until all currently executing tasks for this taskqueue 390 * complete. Tasks that begin execution during the execution 391 * of this function are ignored. 392 */ 393 static int 394 taskqueue_drain_tq_active(struct taskqueue *queue) 395 { 396 struct taskqueue_busy *tb; 397 u_int seq; 398 399 if (LIST_EMPTY(&queue->tq_active)) 400 return (0); 401 402 /* Block taskq_terminate().*/ 403 queue->tq_callouts++; 404 405 /* Wait for any active task with sequence from the past. */ 406 seq = queue->tq_seq; 407 restart: 408 LIST_FOREACH(tb, &queue->tq_active, tb_link) { 409 if ((int)(tb->tb_seq - seq) <= 0) { 410 TQ_SLEEP(queue, tb->tb_running, "tq_adrain"); 411 goto restart; 412 } 413 } 414 415 /* Release taskqueue_terminate(). */ 416 queue->tq_callouts--; 417 if ((queue->tq_flags & TQ_FLAGS_ACTIVE) == 0) 418 wakeup_one(queue->tq_threads); 419 return (1); 420 } 421 422 void 423 taskqueue_block(struct taskqueue *queue) 424 { 425 426 TQ_LOCK(queue); 427 queue->tq_flags |= TQ_FLAGS_BLOCKED; 428 TQ_UNLOCK(queue); 429 } 430 431 void 432 taskqueue_unblock(struct taskqueue *queue) 433 { 434 435 TQ_LOCK(queue); 436 queue->tq_flags &= ~TQ_FLAGS_BLOCKED; 437 if (!STAILQ_EMPTY(&queue->tq_queue)) 438 queue->tq_enqueue(queue->tq_context); 439 TQ_UNLOCK(queue); 440 } 441 442 static void 443 taskqueue_run_locked(struct taskqueue *queue) 444 { 445 struct taskqueue_busy tb; 446 struct task *task; 447 int pending; 448 449 KASSERT(queue != NULL, ("tq is NULL")); 450 TQ_ASSERT_LOCKED(queue); 451 tb.tb_running = NULL; 452 LIST_INSERT_HEAD(&queue->tq_active, &tb, tb_link); 453 454 while ((task = STAILQ_FIRST(&queue->tq_queue)) != NULL) { 455 STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link); 456 if (queue->tq_hint == task) 457 queue->tq_hint = NULL; 458 pending = task->ta_pending; 459 task->ta_pending = 0; 460 tb.tb_running = task; 461 tb.tb_seq = ++queue->tq_seq; 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 wakeup(task); 469 } 470 LIST_REMOVE(&tb, tb_link); 471 } 472 473 void 474 taskqueue_run(struct taskqueue *queue) 475 { 476 477 TQ_LOCK(queue); 478 taskqueue_run_locked(queue); 479 TQ_UNLOCK(queue); 480 } 481 482 static int 483 task_is_running(struct taskqueue *queue, struct task *task) 484 { 485 struct taskqueue_busy *tb; 486 487 TQ_ASSERT_LOCKED(queue); 488 LIST_FOREACH(tb, &queue->tq_active, tb_link) { 489 if (tb->tb_running == task) 490 return (1); 491 } 492 return (0); 493 } 494 495 /* 496 * Only use this function in single threaded contexts. It returns 497 * non-zero if the given task is either pending or running. Else the 498 * task is idle and can be queued again or freed. 499 */ 500 int 501 taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task) 502 { 503 int retval; 504 505 TQ_LOCK(queue); 506 retval = task->ta_pending > 0 || task_is_running(queue, task); 507 TQ_UNLOCK(queue); 508 509 return (retval); 510 } 511 512 static int 513 taskqueue_cancel_locked(struct taskqueue *queue, struct task *task, 514 u_int *pendp) 515 { 516 517 if (task->ta_pending > 0) { 518 STAILQ_REMOVE(&queue->tq_queue, task, task, ta_link); 519 if (queue->tq_hint == task) 520 queue->tq_hint = NULL; 521 } 522 if (pendp != NULL) 523 *pendp = task->ta_pending; 524 task->ta_pending = 0; 525 return (task_is_running(queue, task) ? EBUSY : 0); 526 } 527 528 int 529 taskqueue_cancel(struct taskqueue *queue, struct task *task, u_int *pendp) 530 { 531 int error; 532 533 TQ_LOCK(queue); 534 error = taskqueue_cancel_locked(queue, task, pendp); 535 TQ_UNLOCK(queue); 536 537 return (error); 538 } 539 540 int 541 taskqueue_cancel_timeout(struct taskqueue *queue, 542 struct timeout_task *timeout_task, u_int *pendp) 543 { 544 u_int pending, pending1; 545 int error; 546 547 TQ_LOCK(queue); 548 pending = !!(callout_stop(&timeout_task->c) > 0); 549 error = taskqueue_cancel_locked(queue, &timeout_task->t, &pending1); 550 if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) { 551 timeout_task->f &= ~DT_CALLOUT_ARMED; 552 queue->tq_callouts--; 553 } 554 TQ_UNLOCK(queue); 555 556 if (pendp != NULL) 557 *pendp = pending + pending1; 558 return (error); 559 } 560 561 void 562 taskqueue_drain(struct taskqueue *queue, struct task *task) 563 { 564 565 if (!queue->tq_spin) 566 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 567 568 TQ_LOCK(queue); 569 while (task->ta_pending != 0 || task_is_running(queue, task)) 570 TQ_SLEEP(queue, task, "tq_drain"); 571 TQ_UNLOCK(queue); 572 } 573 574 void 575 taskqueue_drain_all(struct taskqueue *queue) 576 { 577 578 if (!queue->tq_spin) 579 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 580 581 TQ_LOCK(queue); 582 (void)taskqueue_drain_tq_queue(queue); 583 (void)taskqueue_drain_tq_active(queue); 584 TQ_UNLOCK(queue); 585 } 586 587 void 588 taskqueue_drain_timeout(struct taskqueue *queue, 589 struct timeout_task *timeout_task) 590 { 591 592 /* 593 * Set flag to prevent timer from re-starting during drain: 594 */ 595 TQ_LOCK(queue); 596 KASSERT((timeout_task->f & DT_DRAIN_IN_PROGRESS) == 0, 597 ("Drain already in progress")); 598 timeout_task->f |= DT_DRAIN_IN_PROGRESS; 599 TQ_UNLOCK(queue); 600 601 callout_drain(&timeout_task->c); 602 taskqueue_drain(queue, &timeout_task->t); 603 604 /* 605 * Clear flag to allow timer to re-start: 606 */ 607 TQ_LOCK(queue); 608 timeout_task->f &= ~DT_DRAIN_IN_PROGRESS; 609 TQ_UNLOCK(queue); 610 } 611 612 void 613 taskqueue_quiesce(struct taskqueue *queue) 614 { 615 int ret; 616 617 TQ_LOCK(queue); 618 do { 619 ret = taskqueue_drain_tq_queue(queue); 620 if (ret == 0) 621 ret = taskqueue_drain_tq_active(queue); 622 } while (ret != 0); 623 TQ_UNLOCK(queue); 624 } 625 626 static void 627 taskqueue_swi_enqueue(void *context) 628 { 629 swi_sched(taskqueue_ih, 0); 630 } 631 632 static void 633 taskqueue_swi_run(void *dummy) 634 { 635 taskqueue_run(taskqueue_swi); 636 } 637 638 static void 639 taskqueue_swi_giant_enqueue(void *context) 640 { 641 swi_sched(taskqueue_giant_ih, 0); 642 } 643 644 static void 645 taskqueue_swi_giant_run(void *dummy) 646 { 647 taskqueue_run(taskqueue_swi_giant); 648 } 649 650 static int 651 _taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 652 cpuset_t *mask, struct proc *p, const char *name, va_list ap) 653 { 654 char ktname[MAXCOMLEN + 1]; 655 struct thread *td; 656 struct taskqueue *tq; 657 int i, error; 658 659 if (count <= 0) 660 return (EINVAL); 661 662 vsnprintf(ktname, sizeof(ktname), name, ap); 663 tq = *tqp; 664 665 tq->tq_threads = malloc(sizeof(struct thread *) * count, M_TASKQUEUE, 666 M_NOWAIT | M_ZERO); 667 if (tq->tq_threads == NULL) { 668 printf("%s: no memory for %s threads\n", __func__, ktname); 669 return (ENOMEM); 670 } 671 672 for (i = 0; i < count; i++) { 673 if (count == 1) 674 error = kthread_add(taskqueue_thread_loop, tqp, p, 675 &tq->tq_threads[i], RFSTOPPED, 0, "%s", ktname); 676 else 677 error = kthread_add(taskqueue_thread_loop, tqp, p, 678 &tq->tq_threads[i], RFSTOPPED, 0, 679 "%s_%d", ktname, i); 680 if (error) { 681 /* should be ok to continue, taskqueue_free will dtrt */ 682 printf("%s: kthread_add(%s): error %d", __func__, 683 ktname, error); 684 tq->tq_threads[i] = NULL; /* paranoid */ 685 } else 686 tq->tq_tcount++; 687 } 688 if (tq->tq_tcount == 0) { 689 free(tq->tq_threads, M_TASKQUEUE); 690 tq->tq_threads = NULL; 691 return (ENOMEM); 692 } 693 for (i = 0; i < count; i++) { 694 if (tq->tq_threads[i] == NULL) 695 continue; 696 td = tq->tq_threads[i]; 697 if (mask) { 698 error = cpuset_setthread(td->td_tid, mask); 699 /* 700 * Failing to pin is rarely an actual fatal error; 701 * it'll just affect performance. 702 */ 703 if (error) 704 printf("%s: curthread=%llu: can't pin; " 705 "error=%d\n", 706 __func__, 707 (unsigned long long) td->td_tid, 708 error); 709 } 710 thread_lock(td); 711 sched_prio(td, pri); 712 sched_add(td, SRQ_BORING); 713 } 714 715 return (0); 716 } 717 718 int 719 taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 720 const char *name, ...) 721 { 722 va_list ap; 723 int error; 724 725 va_start(ap, name); 726 error = _taskqueue_start_threads(tqp, count, pri, NULL, NULL, name, ap); 727 va_end(ap); 728 return (error); 729 } 730 731 int 732 taskqueue_start_threads_in_proc(struct taskqueue **tqp, int count, int pri, 733 struct proc *proc, const char *name, ...) 734 { 735 va_list ap; 736 int error; 737 738 va_start(ap, name); 739 error = _taskqueue_start_threads(tqp, count, pri, NULL, proc, name, ap); 740 va_end(ap); 741 return (error); 742 } 743 744 int 745 taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count, int pri, 746 cpuset_t *mask, const char *name, ...) 747 { 748 va_list ap; 749 int error; 750 751 va_start(ap, name); 752 error = _taskqueue_start_threads(tqp, count, pri, mask, NULL, name, ap); 753 va_end(ap); 754 return (error); 755 } 756 757 static inline void 758 taskqueue_run_callback(struct taskqueue *tq, 759 enum taskqueue_callback_type cb_type) 760 { 761 taskqueue_callback_fn tq_callback; 762 763 TQ_ASSERT_UNLOCKED(tq); 764 tq_callback = tq->tq_callbacks[cb_type]; 765 if (tq_callback != NULL) 766 tq_callback(tq->tq_cb_contexts[cb_type]); 767 } 768 769 void 770 taskqueue_thread_loop(void *arg) 771 { 772 struct taskqueue **tqp, *tq; 773 774 tqp = arg; 775 tq = *tqp; 776 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_INIT); 777 TQ_LOCK(tq); 778 while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) { 779 /* XXX ? */ 780 taskqueue_run_locked(tq); 781 /* 782 * Because taskqueue_run() can drop tq_mutex, we need to 783 * check if the TQ_FLAGS_ACTIVE flag wasn't removed in the 784 * meantime, which means we missed a wakeup. 785 */ 786 if ((tq->tq_flags & TQ_FLAGS_ACTIVE) == 0) 787 break; 788 TQ_SLEEP(tq, tq, "-"); 789 } 790 taskqueue_run_locked(tq); 791 /* 792 * This thread is on its way out, so just drop the lock temporarily 793 * in order to call the shutdown callback. This allows the callback 794 * to look at the taskqueue, even just before it dies. 795 */ 796 TQ_UNLOCK(tq); 797 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN); 798 TQ_LOCK(tq); 799 800 /* rendezvous with thread that asked us to terminate */ 801 tq->tq_tcount--; 802 wakeup_one(tq->tq_threads); 803 TQ_UNLOCK(tq); 804 kthread_exit(); 805 } 806 807 void 808 taskqueue_thread_enqueue(void *context) 809 { 810 struct taskqueue **tqp, *tq; 811 812 tqp = context; 813 tq = *tqp; 814 wakeup_any(tq); 815 } 816 817 TASKQUEUE_DEFINE(swi, taskqueue_swi_enqueue, NULL, 818 swi_add(NULL, "task queue", taskqueue_swi_run, NULL, SWI_TQ, 819 INTR_MPSAFE, &taskqueue_ih)); 820 821 TASKQUEUE_DEFINE(swi_giant, taskqueue_swi_giant_enqueue, NULL, 822 swi_add(NULL, "Giant taskq", taskqueue_swi_giant_run, 823 NULL, SWI_TQ_GIANT, 0, &taskqueue_giant_ih)); 824 825 TASKQUEUE_DEFINE_THREAD(thread); 826 827 struct taskqueue * 828 taskqueue_create_fast(const char *name, int mflags, 829 taskqueue_enqueue_fn enqueue, void *context) 830 { 831 return _taskqueue_create(name, mflags, enqueue, context, 832 MTX_SPIN, "fast_taskqueue"); 833 } 834 835 static void *taskqueue_fast_ih; 836 837 static void 838 taskqueue_fast_enqueue(void *context) 839 { 840 swi_sched(taskqueue_fast_ih, 0); 841 } 842 843 static void 844 taskqueue_fast_run(void *dummy) 845 { 846 taskqueue_run(taskqueue_fast); 847 } 848 849 TASKQUEUE_FAST_DEFINE(fast, taskqueue_fast_enqueue, NULL, 850 swi_add(NULL, "fast taskq", taskqueue_fast_run, NULL, 851 SWI_TQ_FAST, INTR_MPSAFE, &taskqueue_fast_ih)); 852 853 int 854 taskqueue_member(struct taskqueue *queue, struct thread *td) 855 { 856 int i, j, ret = 0; 857 858 for (i = 0, j = 0; ; i++) { 859 if (queue->tq_threads[i] == NULL) 860 continue; 861 if (queue->tq_threads[i] == td) { 862 ret = 1; 863 break; 864 } 865 if (++j >= queue->tq_tcount) 866 break; 867 } 868 return (ret); 869 } 870