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 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/bus.h> 33 #include <sys/cpuset.h> 34 #include <sys/interrupt.h> 35 #include <sys/kernel.h> 36 #include <sys/kthread.h> 37 #include <sys/libkern.h> 38 #include <sys/limits.h> 39 #include <sys/lock.h> 40 #include <sys/malloc.h> 41 #include <sys/mutex.h> 42 #include <sys/proc.h> 43 #include <sys/sched.h> 44 #include <sys/smp.h> 45 #include <sys/taskqueue.h> 46 #include <sys/unistd.h> 47 #include <machine/stdarg.h> 48 49 static MALLOC_DEFINE(M_TASKQUEUE, "taskqueue", "Task Queues"); 50 static void *taskqueue_giant_ih; 51 static void *taskqueue_ih; 52 static void taskqueue_fast_enqueue(void *); 53 static void taskqueue_swi_enqueue(void *); 54 static void taskqueue_swi_giant_enqueue(void *); 55 56 struct taskqueue_busy { 57 struct task *tb_running; 58 TAILQ_ENTRY(taskqueue_busy) tb_link; 59 }; 60 61 struct task * const TB_DRAIN_WAITER = (struct task *)0x1; 62 63 struct taskqueue { 64 STAILQ_HEAD(, task) tq_queue; 65 taskqueue_enqueue_fn tq_enqueue; 66 void *tq_context; 67 char *tq_name; 68 TAILQ_HEAD(, taskqueue_busy) tq_active; 69 struct mtx tq_mutex; 70 struct thread **tq_threads; 71 int tq_tcount; 72 int tq_spin; 73 int tq_flags; 74 int tq_callouts; 75 taskqueue_callback_fn tq_callbacks[TASKQUEUE_NUM_CALLBACKS]; 76 void *tq_cb_contexts[TASKQUEUE_NUM_CALLBACKS]; 77 }; 78 79 #define TQ_FLAGS_ACTIVE (1 << 0) 80 #define TQ_FLAGS_BLOCKED (1 << 1) 81 #define TQ_FLAGS_UNLOCKED_ENQUEUE (1 << 2) 82 83 #define DT_CALLOUT_ARMED (1 << 0) 84 #define DT_DRAIN_IN_PROGRESS (1 << 1) 85 86 #define TQ_LOCK(tq) \ 87 do { \ 88 if ((tq)->tq_spin) \ 89 mtx_lock_spin(&(tq)->tq_mutex); \ 90 else \ 91 mtx_lock(&(tq)->tq_mutex); \ 92 } while (0) 93 #define TQ_ASSERT_LOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_OWNED) 94 95 #define TQ_UNLOCK(tq) \ 96 do { \ 97 if ((tq)->tq_spin) \ 98 mtx_unlock_spin(&(tq)->tq_mutex); \ 99 else \ 100 mtx_unlock(&(tq)->tq_mutex); \ 101 } while (0) 102 #define TQ_ASSERT_UNLOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_NOTOWNED) 103 104 void 105 _timeout_task_init(struct taskqueue *queue, struct timeout_task *timeout_task, 106 int priority, task_fn_t func, void *context) 107 { 108 109 TASK_INIT(&timeout_task->t, priority, func, context); 110 callout_init_mtx(&timeout_task->c, &queue->tq_mutex, 111 CALLOUT_RETURNUNLOCKED); 112 timeout_task->q = queue; 113 timeout_task->f = 0; 114 } 115 116 static __inline int 117 TQ_SLEEP(struct taskqueue *tq, void *p, struct mtx *m, int pri, const char *wm, 118 int t) 119 { 120 if (tq->tq_spin) 121 return (msleep_spin(p, m, wm, t)); 122 return (msleep(p, m, pri, wm, t)); 123 } 124 125 static struct taskqueue * 126 _taskqueue_create(const char *name, int mflags, 127 taskqueue_enqueue_fn enqueue, void *context, 128 int mtxflags, const char *mtxname __unused) 129 { 130 struct taskqueue *queue; 131 char *tq_name; 132 133 tq_name = malloc(TASKQUEUE_NAMELEN, M_TASKQUEUE, mflags | M_ZERO); 134 if (tq_name == NULL) 135 return (NULL); 136 137 queue = malloc(sizeof(struct taskqueue), M_TASKQUEUE, mflags | M_ZERO); 138 if (queue == NULL) { 139 free(tq_name, M_TASKQUEUE); 140 return (NULL); 141 } 142 143 snprintf(tq_name, TASKQUEUE_NAMELEN, "%s", (name) ? name : "taskqueue"); 144 145 STAILQ_INIT(&queue->tq_queue); 146 TAILQ_INIT(&queue->tq_active); 147 queue->tq_enqueue = enqueue; 148 queue->tq_context = context; 149 queue->tq_name = tq_name; 150 queue->tq_spin = (mtxflags & MTX_SPIN) != 0; 151 queue->tq_flags |= TQ_FLAGS_ACTIVE; 152 if (enqueue == taskqueue_fast_enqueue || 153 enqueue == taskqueue_swi_enqueue || 154 enqueue == taskqueue_swi_giant_enqueue || 155 enqueue == taskqueue_thread_enqueue) 156 queue->tq_flags |= TQ_FLAGS_UNLOCKED_ENQUEUE; 157 mtx_init(&queue->tq_mutex, tq_name, NULL, mtxflags); 158 159 return (queue); 160 } 161 162 struct taskqueue * 163 taskqueue_create(const char *name, int mflags, 164 taskqueue_enqueue_fn enqueue, void *context) 165 { 166 167 return _taskqueue_create(name, mflags, enqueue, context, 168 MTX_DEF, name); 169 } 170 171 void 172 taskqueue_set_callback(struct taskqueue *queue, 173 enum taskqueue_callback_type cb_type, taskqueue_callback_fn callback, 174 void *context) 175 { 176 177 KASSERT(((cb_type >= TASKQUEUE_CALLBACK_TYPE_MIN) && 178 (cb_type <= TASKQUEUE_CALLBACK_TYPE_MAX)), 179 ("Callback type %d not valid, must be %d-%d", cb_type, 180 TASKQUEUE_CALLBACK_TYPE_MIN, TASKQUEUE_CALLBACK_TYPE_MAX)); 181 KASSERT((queue->tq_callbacks[cb_type] == NULL), 182 ("Re-initialization of taskqueue callback?")); 183 184 queue->tq_callbacks[cb_type] = callback; 185 queue->tq_cb_contexts[cb_type] = context; 186 } 187 188 /* 189 * Signal a taskqueue thread to terminate. 190 */ 191 static void 192 taskqueue_terminate(struct thread **pp, struct taskqueue *tq) 193 { 194 195 while (tq->tq_tcount > 0 || tq->tq_callouts > 0) { 196 wakeup(tq); 197 TQ_SLEEP(tq, pp, &tq->tq_mutex, PWAIT, "taskqueue_destroy", 0); 198 } 199 } 200 201 void 202 taskqueue_free(struct taskqueue *queue) 203 { 204 205 TQ_LOCK(queue); 206 queue->tq_flags &= ~TQ_FLAGS_ACTIVE; 207 taskqueue_terminate(queue->tq_threads, queue); 208 KASSERT(TAILQ_EMPTY(&queue->tq_active), ("Tasks still running?")); 209 KASSERT(queue->tq_callouts == 0, ("Armed timeout tasks")); 210 mtx_destroy(&queue->tq_mutex); 211 free(queue->tq_threads, M_TASKQUEUE); 212 free(queue->tq_name, M_TASKQUEUE); 213 free(queue, M_TASKQUEUE); 214 } 215 216 static int 217 taskqueue_enqueue_locked(struct taskqueue *queue, struct task *task) 218 { 219 struct task *ins; 220 struct task *prev; 221 222 KASSERT(task->ta_func != NULL, ("enqueueing task with NULL func")); 223 /* 224 * Count multiple enqueues. 225 */ 226 if (task->ta_pending) { 227 if (task->ta_pending < USHRT_MAX) 228 task->ta_pending++; 229 TQ_UNLOCK(queue); 230 return (0); 231 } 232 233 /* 234 * Optimise the case when all tasks have the same priority. 235 */ 236 prev = STAILQ_LAST(&queue->tq_queue, task, ta_link); 237 if (!prev || prev->ta_priority >= task->ta_priority) { 238 STAILQ_INSERT_TAIL(&queue->tq_queue, task, ta_link); 239 } else { 240 prev = NULL; 241 for (ins = STAILQ_FIRST(&queue->tq_queue); ins; 242 prev = ins, ins = STAILQ_NEXT(ins, ta_link)) 243 if (ins->ta_priority < task->ta_priority) 244 break; 245 246 if (prev) 247 STAILQ_INSERT_AFTER(&queue->tq_queue, prev, task, ta_link); 248 else 249 STAILQ_INSERT_HEAD(&queue->tq_queue, task, ta_link); 250 } 251 252 task->ta_pending = 1; 253 if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) != 0) 254 TQ_UNLOCK(queue); 255 if ((queue->tq_flags & TQ_FLAGS_BLOCKED) == 0) 256 queue->tq_enqueue(queue->tq_context); 257 if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) == 0) 258 TQ_UNLOCK(queue); 259 260 /* Return with lock released. */ 261 return (0); 262 } 263 264 int 265 taskqueue_enqueue(struct taskqueue *queue, struct task *task) 266 { 267 int res; 268 269 TQ_LOCK(queue); 270 res = taskqueue_enqueue_locked(queue, task); 271 /* The lock is released inside. */ 272 273 return (res); 274 } 275 276 static void 277 taskqueue_timeout_func(void *arg) 278 { 279 struct taskqueue *queue; 280 struct timeout_task *timeout_task; 281 282 timeout_task = arg; 283 queue = timeout_task->q; 284 KASSERT((timeout_task->f & DT_CALLOUT_ARMED) != 0, ("Stray timeout")); 285 timeout_task->f &= ~DT_CALLOUT_ARMED; 286 queue->tq_callouts--; 287 taskqueue_enqueue_locked(timeout_task->q, &timeout_task->t); 288 /* The lock is released inside. */ 289 } 290 291 int 292 taskqueue_enqueue_timeout(struct taskqueue *queue, 293 struct timeout_task *timeout_task, int ticks) 294 { 295 int res; 296 297 TQ_LOCK(queue); 298 KASSERT(timeout_task->q == NULL || timeout_task->q == queue, 299 ("Migrated queue")); 300 KASSERT(!queue->tq_spin, ("Timeout for spin-queue")); 301 timeout_task->q = queue; 302 res = timeout_task->t.ta_pending; 303 if (timeout_task->f & DT_DRAIN_IN_PROGRESS) { 304 /* Do nothing */ 305 TQ_UNLOCK(queue); 306 res = -1; 307 } else if (ticks == 0) { 308 taskqueue_enqueue_locked(queue, &timeout_task->t); 309 /* The lock is released inside. */ 310 } else { 311 if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) { 312 res++; 313 } else { 314 queue->tq_callouts++; 315 timeout_task->f |= DT_CALLOUT_ARMED; 316 if (ticks < 0) 317 ticks = -ticks; /* Ignore overflow. */ 318 } 319 if (ticks > 0) { 320 callout_reset(&timeout_task->c, ticks, 321 taskqueue_timeout_func, timeout_task); 322 } 323 TQ_UNLOCK(queue); 324 } 325 return (res); 326 } 327 328 static void 329 taskqueue_task_nop_fn(void *context, int pending) 330 { 331 } 332 333 /* 334 * Block until all currently queued tasks in this taskqueue 335 * have begun execution. Tasks queued during execution of 336 * this function are ignored. 337 */ 338 static void 339 taskqueue_drain_tq_queue(struct taskqueue *queue) 340 { 341 struct task t_barrier; 342 343 if (STAILQ_EMPTY(&queue->tq_queue)) 344 return; 345 346 /* 347 * Enqueue our barrier after all current tasks, but with 348 * the highest priority so that newly queued tasks cannot 349 * pass it. Because of the high priority, we can not use 350 * taskqueue_enqueue_locked directly (which drops the lock 351 * anyway) so just insert it at tail while we have the 352 * queue lock. 353 */ 354 TASK_INIT(&t_barrier, USHRT_MAX, taskqueue_task_nop_fn, &t_barrier); 355 STAILQ_INSERT_TAIL(&queue->tq_queue, &t_barrier, ta_link); 356 t_barrier.ta_pending = 1; 357 358 /* 359 * Once the barrier has executed, all previously queued tasks 360 * have completed or are currently executing. 361 */ 362 while (t_barrier.ta_pending != 0) 363 TQ_SLEEP(queue, &t_barrier, &queue->tq_mutex, PWAIT, "-", 0); 364 } 365 366 /* 367 * Block until all currently executing tasks for this taskqueue 368 * complete. Tasks that begin execution during the execution 369 * of this function are ignored. 370 */ 371 static void 372 taskqueue_drain_tq_active(struct taskqueue *queue) 373 { 374 struct taskqueue_busy tb_marker, *tb_first; 375 376 if (TAILQ_EMPTY(&queue->tq_active)) 377 return; 378 379 /* Block taskq_terminate().*/ 380 queue->tq_callouts++; 381 382 /* 383 * Wait for all currently executing taskqueue threads 384 * to go idle. 385 */ 386 tb_marker.tb_running = TB_DRAIN_WAITER; 387 TAILQ_INSERT_TAIL(&queue->tq_active, &tb_marker, tb_link); 388 while (TAILQ_FIRST(&queue->tq_active) != &tb_marker) 389 TQ_SLEEP(queue, &tb_marker, &queue->tq_mutex, PWAIT, "-", 0); 390 TAILQ_REMOVE(&queue->tq_active, &tb_marker, tb_link); 391 392 /* 393 * Wakeup any other drain waiter that happened to queue up 394 * without any intervening active thread. 395 */ 396 tb_first = TAILQ_FIRST(&queue->tq_active); 397 if (tb_first != NULL && tb_first->tb_running == TB_DRAIN_WAITER) 398 wakeup(tb_first); 399 400 /* Release taskqueue_terminate(). */ 401 queue->tq_callouts--; 402 if ((queue->tq_flags & TQ_FLAGS_ACTIVE) == 0) 403 wakeup_one(queue->tq_threads); 404 } 405 406 void 407 taskqueue_block(struct taskqueue *queue) 408 { 409 410 TQ_LOCK(queue); 411 queue->tq_flags |= TQ_FLAGS_BLOCKED; 412 TQ_UNLOCK(queue); 413 } 414 415 void 416 taskqueue_unblock(struct taskqueue *queue) 417 { 418 419 TQ_LOCK(queue); 420 queue->tq_flags &= ~TQ_FLAGS_BLOCKED; 421 if (!STAILQ_EMPTY(&queue->tq_queue)) 422 queue->tq_enqueue(queue->tq_context); 423 TQ_UNLOCK(queue); 424 } 425 426 static void 427 taskqueue_run_locked(struct taskqueue *queue) 428 { 429 struct taskqueue_busy tb; 430 struct taskqueue_busy *tb_first; 431 struct task *task; 432 int pending; 433 434 KASSERT(queue != NULL, ("tq is NULL")); 435 TQ_ASSERT_LOCKED(queue); 436 tb.tb_running = NULL; 437 438 while (STAILQ_FIRST(&queue->tq_queue)) { 439 TAILQ_INSERT_TAIL(&queue->tq_active, &tb, tb_link); 440 441 /* 442 * Carefully remove the first task from the queue and 443 * zero its pending count. 444 */ 445 task = STAILQ_FIRST(&queue->tq_queue); 446 KASSERT(task != NULL, ("task is NULL")); 447 STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link); 448 pending = task->ta_pending; 449 task->ta_pending = 0; 450 tb.tb_running = task; 451 TQ_UNLOCK(queue); 452 453 KASSERT(task->ta_func != NULL, ("task->ta_func is NULL")); 454 task->ta_func(task->ta_context, pending); 455 456 TQ_LOCK(queue); 457 tb.tb_running = NULL; 458 wakeup(task); 459 460 TAILQ_REMOVE(&queue->tq_active, &tb, tb_link); 461 tb_first = TAILQ_FIRST(&queue->tq_active); 462 if (tb_first != NULL && 463 tb_first->tb_running == TB_DRAIN_WAITER) 464 wakeup(tb_first); 465 } 466 } 467 468 void 469 taskqueue_run(struct taskqueue *queue) 470 { 471 472 TQ_LOCK(queue); 473 taskqueue_run_locked(queue); 474 TQ_UNLOCK(queue); 475 } 476 477 static int 478 task_is_running(struct taskqueue *queue, struct task *task) 479 { 480 struct taskqueue_busy *tb; 481 482 TQ_ASSERT_LOCKED(queue); 483 TAILQ_FOREACH(tb, &queue->tq_active, tb_link) { 484 if (tb->tb_running == task) 485 return (1); 486 } 487 return (0); 488 } 489 490 /* 491 * Only use this function in single threaded contexts. It returns 492 * non-zero if the given task is either pending or running. Else the 493 * task is idle and can be queued again or freed. 494 */ 495 int 496 taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task) 497 { 498 int retval; 499 500 TQ_LOCK(queue); 501 retval = task->ta_pending > 0 || task_is_running(queue, task); 502 TQ_UNLOCK(queue); 503 504 return (retval); 505 } 506 507 static int 508 taskqueue_cancel_locked(struct taskqueue *queue, struct task *task, 509 u_int *pendp) 510 { 511 512 if (task->ta_pending > 0) 513 STAILQ_REMOVE(&queue->tq_queue, task, task, ta_link); 514 if (pendp != NULL) 515 *pendp = task->ta_pending; 516 task->ta_pending = 0; 517 return (task_is_running(queue, task) ? EBUSY : 0); 518 } 519 520 int 521 taskqueue_cancel(struct taskqueue *queue, struct task *task, u_int *pendp) 522 { 523 int error; 524 525 TQ_LOCK(queue); 526 error = taskqueue_cancel_locked(queue, task, pendp); 527 TQ_UNLOCK(queue); 528 529 return (error); 530 } 531 532 int 533 taskqueue_cancel_timeout(struct taskqueue *queue, 534 struct timeout_task *timeout_task, u_int *pendp) 535 { 536 u_int pending, pending1; 537 int error; 538 539 TQ_LOCK(queue); 540 pending = !!(callout_stop(&timeout_task->c) > 0); 541 error = taskqueue_cancel_locked(queue, &timeout_task->t, &pending1); 542 if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) { 543 timeout_task->f &= ~DT_CALLOUT_ARMED; 544 queue->tq_callouts--; 545 } 546 TQ_UNLOCK(queue); 547 548 if (pendp != NULL) 549 *pendp = pending + pending1; 550 return (error); 551 } 552 553 void 554 taskqueue_drain(struct taskqueue *queue, struct task *task) 555 { 556 557 if (!queue->tq_spin) 558 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 559 560 TQ_LOCK(queue); 561 while (task->ta_pending != 0 || task_is_running(queue, task)) 562 TQ_SLEEP(queue, task, &queue->tq_mutex, PWAIT, "-", 0); 563 TQ_UNLOCK(queue); 564 } 565 566 void 567 taskqueue_drain_all(struct taskqueue *queue) 568 { 569 570 if (!queue->tq_spin) 571 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 572 573 TQ_LOCK(queue); 574 taskqueue_drain_tq_queue(queue); 575 taskqueue_drain_tq_active(queue); 576 TQ_UNLOCK(queue); 577 } 578 579 void 580 taskqueue_drain_timeout(struct taskqueue *queue, 581 struct timeout_task *timeout_task) 582 { 583 584 /* 585 * Set flag to prevent timer from re-starting during drain: 586 */ 587 TQ_LOCK(queue); 588 KASSERT((timeout_task->f & DT_DRAIN_IN_PROGRESS) == 0, 589 ("Drain already in progress")); 590 timeout_task->f |= DT_DRAIN_IN_PROGRESS; 591 TQ_UNLOCK(queue); 592 593 callout_drain(&timeout_task->c); 594 taskqueue_drain(queue, &timeout_task->t); 595 596 /* 597 * Clear flag to allow timer to re-start: 598 */ 599 TQ_LOCK(queue); 600 timeout_task->f &= ~DT_DRAIN_IN_PROGRESS; 601 TQ_UNLOCK(queue); 602 } 603 604 static void 605 taskqueue_swi_enqueue(void *context) 606 { 607 swi_sched(taskqueue_ih, 0); 608 } 609 610 static void 611 taskqueue_swi_run(void *dummy) 612 { 613 taskqueue_run(taskqueue_swi); 614 } 615 616 static void 617 taskqueue_swi_giant_enqueue(void *context) 618 { 619 swi_sched(taskqueue_giant_ih, 0); 620 } 621 622 static void 623 taskqueue_swi_giant_run(void *dummy) 624 { 625 taskqueue_run(taskqueue_swi_giant); 626 } 627 628 static int 629 _taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 630 cpuset_t *mask, const char *name, va_list ap) 631 { 632 char ktname[MAXCOMLEN + 1]; 633 struct thread *td; 634 struct taskqueue *tq; 635 int i, error; 636 637 if (count <= 0) 638 return (EINVAL); 639 640 vsnprintf(ktname, sizeof(ktname), name, ap); 641 tq = *tqp; 642 643 tq->tq_threads = malloc(sizeof(struct thread *) * count, M_TASKQUEUE, 644 M_NOWAIT | M_ZERO); 645 if (tq->tq_threads == NULL) { 646 printf("%s: no memory for %s threads\n", __func__, ktname); 647 return (ENOMEM); 648 } 649 650 for (i = 0; i < count; i++) { 651 if (count == 1) 652 error = kthread_add(taskqueue_thread_loop, tqp, NULL, 653 &tq->tq_threads[i], RFSTOPPED, 0, "%s", ktname); 654 else 655 error = kthread_add(taskqueue_thread_loop, tqp, NULL, 656 &tq->tq_threads[i], RFSTOPPED, 0, 657 "%s_%d", ktname, i); 658 if (error) { 659 /* should be ok to continue, taskqueue_free will dtrt */ 660 printf("%s: kthread_add(%s): error %d", __func__, 661 ktname, error); 662 tq->tq_threads[i] = NULL; /* paranoid */ 663 } else 664 tq->tq_tcount++; 665 } 666 if (tq->tq_tcount == 0) { 667 free(tq->tq_threads, M_TASKQUEUE); 668 tq->tq_threads = NULL; 669 return (ENOMEM); 670 } 671 for (i = 0; i < count; i++) { 672 if (tq->tq_threads[i] == NULL) 673 continue; 674 td = tq->tq_threads[i]; 675 if (mask) { 676 error = cpuset_setthread(td->td_tid, mask); 677 /* 678 * Failing to pin is rarely an actual fatal error; 679 * it'll just affect performance. 680 */ 681 if (error) 682 printf("%s: curthread=%llu: can't pin; " 683 "error=%d\n", 684 __func__, 685 (unsigned long long) td->td_tid, 686 error); 687 } 688 thread_lock(td); 689 sched_prio(td, pri); 690 sched_add(td, SRQ_BORING); 691 thread_unlock(td); 692 } 693 694 return (0); 695 } 696 697 int 698 taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 699 const char *name, ...) 700 { 701 va_list ap; 702 int error; 703 704 va_start(ap, name); 705 error = _taskqueue_start_threads(tqp, count, pri, NULL, name, ap); 706 va_end(ap); 707 return (error); 708 } 709 710 int 711 taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count, int pri, 712 cpuset_t *mask, const char *name, ...) 713 { 714 va_list ap; 715 int error; 716 717 va_start(ap, name); 718 error = _taskqueue_start_threads(tqp, count, pri, mask, name, ap); 719 va_end(ap); 720 return (error); 721 } 722 723 static inline void 724 taskqueue_run_callback(struct taskqueue *tq, 725 enum taskqueue_callback_type cb_type) 726 { 727 taskqueue_callback_fn tq_callback; 728 729 TQ_ASSERT_UNLOCKED(tq); 730 tq_callback = tq->tq_callbacks[cb_type]; 731 if (tq_callback != NULL) 732 tq_callback(tq->tq_cb_contexts[cb_type]); 733 } 734 735 void 736 taskqueue_thread_loop(void *arg) 737 { 738 struct taskqueue **tqp, *tq; 739 740 tqp = arg; 741 tq = *tqp; 742 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_INIT); 743 TQ_LOCK(tq); 744 while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) { 745 /* XXX ? */ 746 taskqueue_run_locked(tq); 747 /* 748 * Because taskqueue_run() can drop tq_mutex, we need to 749 * check if the TQ_FLAGS_ACTIVE flag wasn't removed in the 750 * meantime, which means we missed a wakeup. 751 */ 752 if ((tq->tq_flags & TQ_FLAGS_ACTIVE) == 0) 753 break; 754 TQ_SLEEP(tq, tq, &tq->tq_mutex, 0, "-", 0); 755 } 756 taskqueue_run_locked(tq); 757 /* 758 * This thread is on its way out, so just drop the lock temporarily 759 * in order to call the shutdown callback. This allows the callback 760 * to look at the taskqueue, even just before it dies. 761 */ 762 TQ_UNLOCK(tq); 763 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN); 764 TQ_LOCK(tq); 765 766 /* rendezvous with thread that asked us to terminate */ 767 tq->tq_tcount--; 768 wakeup_one(tq->tq_threads); 769 TQ_UNLOCK(tq); 770 kthread_exit(); 771 } 772 773 void 774 taskqueue_thread_enqueue(void *context) 775 { 776 struct taskqueue **tqp, *tq; 777 778 tqp = context; 779 tq = *tqp; 780 wakeup_one(tq); 781 } 782 783 TASKQUEUE_DEFINE(swi, taskqueue_swi_enqueue, NULL, 784 swi_add(NULL, "task queue", taskqueue_swi_run, NULL, SWI_TQ, 785 INTR_MPSAFE, &taskqueue_ih)); 786 787 TASKQUEUE_DEFINE(swi_giant, taskqueue_swi_giant_enqueue, NULL, 788 swi_add(NULL, "Giant taskq", taskqueue_swi_giant_run, 789 NULL, SWI_TQ_GIANT, 0, &taskqueue_giant_ih)); 790 791 TASKQUEUE_DEFINE_THREAD(thread); 792 793 struct taskqueue * 794 taskqueue_create_fast(const char *name, int mflags, 795 taskqueue_enqueue_fn enqueue, void *context) 796 { 797 return _taskqueue_create(name, mflags, enqueue, context, 798 MTX_SPIN, "fast_taskqueue"); 799 } 800 801 static void *taskqueue_fast_ih; 802 803 static void 804 taskqueue_fast_enqueue(void *context) 805 { 806 swi_sched(taskqueue_fast_ih, 0); 807 } 808 809 static void 810 taskqueue_fast_run(void *dummy) 811 { 812 taskqueue_run(taskqueue_fast); 813 } 814 815 TASKQUEUE_FAST_DEFINE(fast, taskqueue_fast_enqueue, NULL, 816 swi_add(NULL, "fast taskq", taskqueue_fast_run, NULL, 817 SWI_TQ_FAST, INTR_MPSAFE, &taskqueue_fast_ih)); 818 819 int 820 taskqueue_member(struct taskqueue *queue, struct thread *td) 821 { 822 int i, j, ret = 0; 823 824 for (i = 0, j = 0; ; i++) { 825 if (queue->tq_threads[i] == NULL) 826 continue; 827 if (queue->tq_threads[i] == td) { 828 ret = 1; 829 break; 830 } 831 if (++j >= queue->tq_tcount) 832 break; 833 } 834 return (ret); 835 } 836