subr_taskqueue.c revision 323447
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: stable/11/sys/kern/subr_taskqueue.c 323447 2017-09-11 17:32:26Z ian $"); 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 49static MALLOC_DEFINE(M_TASKQUEUE, "taskqueue", "Task Queues"); 50static void *taskqueue_giant_ih; 51static void *taskqueue_ih; 52static void taskqueue_fast_enqueue(void *); 53static void taskqueue_swi_enqueue(void *); 54static void taskqueue_swi_giant_enqueue(void *); 55 56struct taskqueue_busy { 57 struct task *tb_running; 58 TAILQ_ENTRY(taskqueue_busy) tb_link; 59}; 60 61struct task * const TB_DRAIN_WAITER = (struct task *)0x1; 62 63struct 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 104void 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 116static __inline int 117TQ_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 125static 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 162struct taskqueue * 163taskqueue_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 171void 172taskqueue_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 */ 191static void 192taskqueue_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 201void 202taskqueue_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 216static int 217taskqueue_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 264int 265taskqueue_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 276static void 277taskqueue_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 291int 292taskqueue_enqueue_timeout_sbt(struct taskqueue *queue, 293 struct timeout_task *timeout_task, sbintime_t sbt, sbintime_t pr, int flags) 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 (sbt == 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 (sbt < 0) 317 sbt = -sbt; /* Ignore overflow. */ 318 } 319 if (sbt > 0) { 320 callout_reset_sbt(&timeout_task->c, sbt, pr, 321 taskqueue_timeout_func, timeout_task, flags); 322 } 323 TQ_UNLOCK(queue); 324 } 325 return (res); 326} 327 328int 329taskqueue_enqueue_timeout(struct taskqueue *queue, 330 struct timeout_task *ttask, int ticks) 331{ 332 333 return (taskqueue_enqueue_timeout_sbt(queue, ttask, ticks * tick_sbt, 334 0, 0)); 335} 336 337static void 338taskqueue_task_nop_fn(void *context, int pending) 339{ 340} 341 342/* 343 * Block until all currently queued tasks in this taskqueue 344 * have begun execution. Tasks queued during execution of 345 * this function are ignored. 346 */ 347static void 348taskqueue_drain_tq_queue(struct taskqueue *queue) 349{ 350 struct task t_barrier; 351 352 if (STAILQ_EMPTY(&queue->tq_queue)) 353 return; 354 355 /* 356 * Enqueue our barrier after all current tasks, but with 357 * the highest priority so that newly queued tasks cannot 358 * pass it. Because of the high priority, we can not use 359 * taskqueue_enqueue_locked directly (which drops the lock 360 * anyway) so just insert it at tail while we have the 361 * queue lock. 362 */ 363 TASK_INIT(&t_barrier, USHRT_MAX, taskqueue_task_nop_fn, &t_barrier); 364 STAILQ_INSERT_TAIL(&queue->tq_queue, &t_barrier, ta_link); 365 t_barrier.ta_pending = 1; 366 367 /* 368 * Once the barrier has executed, all previously queued tasks 369 * have completed or are currently executing. 370 */ 371 while (t_barrier.ta_pending != 0) 372 TQ_SLEEP(queue, &t_barrier, &queue->tq_mutex, PWAIT, "-", 0); 373} 374 375/* 376 * Block until all currently executing tasks for this taskqueue 377 * complete. Tasks that begin execution during the execution 378 * of this function are ignored. 379 */ 380static void 381taskqueue_drain_tq_active(struct taskqueue *queue) 382{ 383 struct taskqueue_busy tb_marker, *tb_first; 384 385 if (TAILQ_EMPTY(&queue->tq_active)) 386 return; 387 388 /* Block taskq_terminate().*/ 389 queue->tq_callouts++; 390 391 /* 392 * Wait for all currently executing taskqueue threads 393 * to go idle. 394 */ 395 tb_marker.tb_running = TB_DRAIN_WAITER; 396 TAILQ_INSERT_TAIL(&queue->tq_active, &tb_marker, tb_link); 397 while (TAILQ_FIRST(&queue->tq_active) != &tb_marker) 398 TQ_SLEEP(queue, &tb_marker, &queue->tq_mutex, PWAIT, "-", 0); 399 TAILQ_REMOVE(&queue->tq_active, &tb_marker, tb_link); 400 401 /* 402 * Wakeup any other drain waiter that happened to queue up 403 * without any intervening active thread. 404 */ 405 tb_first = TAILQ_FIRST(&queue->tq_active); 406 if (tb_first != NULL && tb_first->tb_running == TB_DRAIN_WAITER) 407 wakeup(tb_first); 408 409 /* Release taskqueue_terminate(). */ 410 queue->tq_callouts--; 411 if ((queue->tq_flags & TQ_FLAGS_ACTIVE) == 0) 412 wakeup_one(queue->tq_threads); 413} 414 415void 416taskqueue_block(struct taskqueue *queue) 417{ 418 419 TQ_LOCK(queue); 420 queue->tq_flags |= TQ_FLAGS_BLOCKED; 421 TQ_UNLOCK(queue); 422} 423 424void 425taskqueue_unblock(struct taskqueue *queue) 426{ 427 428 TQ_LOCK(queue); 429 queue->tq_flags &= ~TQ_FLAGS_BLOCKED; 430 if (!STAILQ_EMPTY(&queue->tq_queue)) 431 queue->tq_enqueue(queue->tq_context); 432 TQ_UNLOCK(queue); 433} 434 435static void 436taskqueue_run_locked(struct taskqueue *queue) 437{ 438 struct taskqueue_busy tb; 439 struct taskqueue_busy *tb_first; 440 struct task *task; 441 int pending; 442 443 KASSERT(queue != NULL, ("tq is NULL")); 444 TQ_ASSERT_LOCKED(queue); 445 tb.tb_running = NULL; 446 447 while (STAILQ_FIRST(&queue->tq_queue)) { 448 TAILQ_INSERT_TAIL(&queue->tq_active, &tb, tb_link); 449 450 /* 451 * Carefully remove the first task from the queue and 452 * zero its pending count. 453 */ 454 task = STAILQ_FIRST(&queue->tq_queue); 455 KASSERT(task != NULL, ("task is NULL")); 456 STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link); 457 pending = task->ta_pending; 458 task->ta_pending = 0; 459 tb.tb_running = task; 460 TQ_UNLOCK(queue); 461 462 KASSERT(task->ta_func != NULL, ("task->ta_func is NULL")); 463 task->ta_func(task->ta_context, pending); 464 465 TQ_LOCK(queue); 466 tb.tb_running = NULL; 467 wakeup(task); 468 469 TAILQ_REMOVE(&queue->tq_active, &tb, tb_link); 470 tb_first = TAILQ_FIRST(&queue->tq_active); 471 if (tb_first != NULL && 472 tb_first->tb_running == TB_DRAIN_WAITER) 473 wakeup(tb_first); 474 } 475} 476 477void 478taskqueue_run(struct taskqueue *queue) 479{ 480 481 TQ_LOCK(queue); 482 taskqueue_run_locked(queue); 483 TQ_UNLOCK(queue); 484} 485 486static int 487task_is_running(struct taskqueue *queue, struct task *task) 488{ 489 struct taskqueue_busy *tb; 490 491 TQ_ASSERT_LOCKED(queue); 492 TAILQ_FOREACH(tb, &queue->tq_active, tb_link) { 493 if (tb->tb_running == task) 494 return (1); 495 } 496 return (0); 497} 498 499/* 500 * Only use this function in single threaded contexts. It returns 501 * non-zero if the given task is either pending or running. Else the 502 * task is idle and can be queued again or freed. 503 */ 504int 505taskqueue_poll_is_busy(struct taskqueue *queue, struct task *task) 506{ 507 int retval; 508 509 TQ_LOCK(queue); 510 retval = task->ta_pending > 0 || task_is_running(queue, task); 511 TQ_UNLOCK(queue); 512 513 return (retval); 514} 515 516static int 517taskqueue_cancel_locked(struct taskqueue *queue, struct task *task, 518 u_int *pendp) 519{ 520 521 if (task->ta_pending > 0) 522 STAILQ_REMOVE(&queue->tq_queue, task, task, ta_link); 523 if (pendp != NULL) 524 *pendp = task->ta_pending; 525 task->ta_pending = 0; 526 return (task_is_running(queue, task) ? EBUSY : 0); 527} 528 529int 530taskqueue_cancel(struct taskqueue *queue, struct task *task, u_int *pendp) 531{ 532 int error; 533 534 TQ_LOCK(queue); 535 error = taskqueue_cancel_locked(queue, task, pendp); 536 TQ_UNLOCK(queue); 537 538 return (error); 539} 540 541int 542taskqueue_cancel_timeout(struct taskqueue *queue, 543 struct timeout_task *timeout_task, u_int *pendp) 544{ 545 u_int pending, pending1; 546 int error; 547 548 TQ_LOCK(queue); 549 pending = !!(callout_stop(&timeout_task->c) > 0); 550 error = taskqueue_cancel_locked(queue, &timeout_task->t, &pending1); 551 if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) { 552 timeout_task->f &= ~DT_CALLOUT_ARMED; 553 queue->tq_callouts--; 554 } 555 TQ_UNLOCK(queue); 556 557 if (pendp != NULL) 558 *pendp = pending + pending1; 559 return (error); 560} 561 562void 563taskqueue_drain(struct taskqueue *queue, struct task *task) 564{ 565 566 if (!queue->tq_spin) 567 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 568 569 TQ_LOCK(queue); 570 while (task->ta_pending != 0 || task_is_running(queue, task)) 571 TQ_SLEEP(queue, task, &queue->tq_mutex, PWAIT, "-", 0); 572 TQ_UNLOCK(queue); 573} 574 575void 576taskqueue_drain_all(struct taskqueue *queue) 577{ 578 579 if (!queue->tq_spin) 580 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 581 582 TQ_LOCK(queue); 583 taskqueue_drain_tq_queue(queue); 584 taskqueue_drain_tq_active(queue); 585 TQ_UNLOCK(queue); 586} 587 588void 589taskqueue_drain_timeout(struct taskqueue *queue, 590 struct timeout_task *timeout_task) 591{ 592 593 /* 594 * Set flag to prevent timer from re-starting during drain: 595 */ 596 TQ_LOCK(queue); 597 KASSERT((timeout_task->f & DT_DRAIN_IN_PROGRESS) == 0, 598 ("Drain already in progress")); 599 timeout_task->f |= DT_DRAIN_IN_PROGRESS; 600 TQ_UNLOCK(queue); 601 602 callout_drain(&timeout_task->c); 603 taskqueue_drain(queue, &timeout_task->t); 604 605 /* 606 * Clear flag to allow timer to re-start: 607 */ 608 TQ_LOCK(queue); 609 timeout_task->f &= ~DT_DRAIN_IN_PROGRESS; 610 TQ_UNLOCK(queue); 611} 612 613static void 614taskqueue_swi_enqueue(void *context) 615{ 616 swi_sched(taskqueue_ih, 0); 617} 618 619static void 620taskqueue_swi_run(void *dummy) 621{ 622 taskqueue_run(taskqueue_swi); 623} 624 625static void 626taskqueue_swi_giant_enqueue(void *context) 627{ 628 swi_sched(taskqueue_giant_ih, 0); 629} 630 631static void 632taskqueue_swi_giant_run(void *dummy) 633{ 634 taskqueue_run(taskqueue_swi_giant); 635} 636 637static int 638_taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 639 cpuset_t *mask, const char *name, va_list ap) 640{ 641 char ktname[MAXCOMLEN + 1]; 642 struct thread *td; 643 struct taskqueue *tq; 644 int i, error; 645 646 if (count <= 0) 647 return (EINVAL); 648 649 vsnprintf(ktname, sizeof(ktname), name, ap); 650 tq = *tqp; 651 652 tq->tq_threads = malloc(sizeof(struct thread *) * count, M_TASKQUEUE, 653 M_NOWAIT | M_ZERO); 654 if (tq->tq_threads == NULL) { 655 printf("%s: no memory for %s threads\n", __func__, ktname); 656 return (ENOMEM); 657 } 658 659 for (i = 0; i < count; i++) { 660 if (count == 1) 661 error = kthread_add(taskqueue_thread_loop, tqp, NULL, 662 &tq->tq_threads[i], RFSTOPPED, 0, "%s", ktname); 663 else 664 error = kthread_add(taskqueue_thread_loop, tqp, NULL, 665 &tq->tq_threads[i], RFSTOPPED, 0, 666 "%s_%d", ktname, i); 667 if (error) { 668 /* should be ok to continue, taskqueue_free will dtrt */ 669 printf("%s: kthread_add(%s): error %d", __func__, 670 ktname, error); 671 tq->tq_threads[i] = NULL; /* paranoid */ 672 } else 673 tq->tq_tcount++; 674 } 675 for (i = 0; i < count; i++) { 676 if (tq->tq_threads[i] == NULL) 677 continue; 678 td = tq->tq_threads[i]; 679 if (mask) { 680 error = cpuset_setthread(td->td_tid, mask); 681 /* 682 * Failing to pin is rarely an actual fatal error; 683 * it'll just affect performance. 684 */ 685 if (error) 686 printf("%s: curthread=%llu: can't pin; " 687 "error=%d\n", 688 __func__, 689 (unsigned long long) td->td_tid, 690 error); 691 } 692 thread_lock(td); 693 sched_prio(td, pri); 694 sched_add(td, SRQ_BORING); 695 thread_unlock(td); 696 } 697 698 return (0); 699} 700 701int 702taskqueue_start_threads(struct taskqueue **tqp, int count, int pri, 703 const char *name, ...) 704{ 705 va_list ap; 706 int error; 707 708 va_start(ap, name); 709 error = _taskqueue_start_threads(tqp, count, pri, NULL, name, ap); 710 va_end(ap); 711 return (error); 712} 713 714int 715taskqueue_start_threads_cpuset(struct taskqueue **tqp, int count, int pri, 716 cpuset_t *mask, const char *name, ...) 717{ 718 va_list ap; 719 int error; 720 721 va_start(ap, name); 722 error = _taskqueue_start_threads(tqp, count, pri, mask, name, ap); 723 va_end(ap); 724 return (error); 725} 726 727static inline void 728taskqueue_run_callback(struct taskqueue *tq, 729 enum taskqueue_callback_type cb_type) 730{ 731 taskqueue_callback_fn tq_callback; 732 733 TQ_ASSERT_UNLOCKED(tq); 734 tq_callback = tq->tq_callbacks[cb_type]; 735 if (tq_callback != NULL) 736 tq_callback(tq->tq_cb_contexts[cb_type]); 737} 738 739void 740taskqueue_thread_loop(void *arg) 741{ 742 struct taskqueue **tqp, *tq; 743 744 tqp = arg; 745 tq = *tqp; 746 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_INIT); 747 TQ_LOCK(tq); 748 while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) { 749 /* XXX ? */ 750 taskqueue_run_locked(tq); 751 /* 752 * Because taskqueue_run() can drop tq_mutex, we need to 753 * check if the TQ_FLAGS_ACTIVE flag wasn't removed in the 754 * meantime, which means we missed a wakeup. 755 */ 756 if ((tq->tq_flags & TQ_FLAGS_ACTIVE) == 0) 757 break; 758 TQ_SLEEP(tq, tq, &tq->tq_mutex, 0, "-", 0); 759 } 760 taskqueue_run_locked(tq); 761 /* 762 * This thread is on its way out, so just drop the lock temporarily 763 * in order to call the shutdown callback. This allows the callback 764 * to look at the taskqueue, even just before it dies. 765 */ 766 TQ_UNLOCK(tq); 767 taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN); 768 TQ_LOCK(tq); 769 770 /* rendezvous with thread that asked us to terminate */ 771 tq->tq_tcount--; 772 wakeup_one(tq->tq_threads); 773 TQ_UNLOCK(tq); 774 kthread_exit(); 775} 776 777void 778taskqueue_thread_enqueue(void *context) 779{ 780 struct taskqueue **tqp, *tq; 781 782 tqp = context; 783 tq = *tqp; 784 wakeup_one(tq); 785} 786 787TASKQUEUE_DEFINE(swi, taskqueue_swi_enqueue, NULL, 788 swi_add(NULL, "task queue", taskqueue_swi_run, NULL, SWI_TQ, 789 INTR_MPSAFE, &taskqueue_ih)); 790 791TASKQUEUE_DEFINE(swi_giant, taskqueue_swi_giant_enqueue, NULL, 792 swi_add(NULL, "Giant taskq", taskqueue_swi_giant_run, 793 NULL, SWI_TQ_GIANT, 0, &taskqueue_giant_ih)); 794 795TASKQUEUE_DEFINE_THREAD(thread); 796 797struct taskqueue * 798taskqueue_create_fast(const char *name, int mflags, 799 taskqueue_enqueue_fn enqueue, void *context) 800{ 801 return _taskqueue_create(name, mflags, enqueue, context, 802 MTX_SPIN, "fast_taskqueue"); 803} 804 805static void *taskqueue_fast_ih; 806 807static void 808taskqueue_fast_enqueue(void *context) 809{ 810 swi_sched(taskqueue_fast_ih, 0); 811} 812 813static void 814taskqueue_fast_run(void *dummy) 815{ 816 taskqueue_run(taskqueue_fast); 817} 818 819TASKQUEUE_FAST_DEFINE(fast, taskqueue_fast_enqueue, NULL, 820 swi_add(NULL, "fast taskq", taskqueue_fast_run, NULL, 821 SWI_TQ_FAST, INTR_MPSAFE, &taskqueue_fast_ih)); 822 823int 824taskqueue_member(struct taskqueue *queue, struct thread *td) 825{ 826 int i, j, ret = 0; 827 828 for (i = 0, j = 0; ; i++) { 829 if (queue->tq_threads[i] == NULL) 830 continue; 831 if (queue->tq_threads[i] == td) { 832 ret = 1; 833 break; 834 } 835 if (++j >= queue->tq_tcount) 836 break; 837 } 838 return (ret); 839} 840