1 /*- 2 * Copyright (c) 2000 Doug Rabson 3 * Copyright (c) 2014 Jeff Roberson 4 * Copyright (c) 2016 Matthew Macy 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/kernel.h> 37 #include <sys/kthread.h> 38 #include <sys/libkern.h> 39 #include <sys/limits.h> 40 #include <sys/lock.h> 41 #include <sys/malloc.h> 42 #include <sys/mutex.h> 43 #include <sys/proc.h> 44 #include <sys/sched.h> 45 #include <sys/smp.h> 46 #include <sys/gtaskqueue.h> 47 #include <sys/unistd.h> 48 #include <machine/stdarg.h> 49 50 static MALLOC_DEFINE(M_GTASKQUEUE, "gtaskqueue", "Group Task Queues"); 51 static void gtaskqueue_thread_enqueue(void *); 52 static void gtaskqueue_thread_loop(void *arg); 53 static int task_is_running(struct gtaskqueue *queue, struct gtask *gtask); 54 static void gtaskqueue_drain_locked(struct gtaskqueue *queue, struct gtask *gtask); 55 56 TASKQGROUP_DEFINE(softirq, mp_ncpus, 1); 57 TASKQGROUP_DEFINE(config, 1, 1); 58 59 struct gtaskqueue_busy { 60 struct gtask *tb_running; 61 u_int tb_seq; 62 LIST_ENTRY(gtaskqueue_busy) tb_link; 63 }; 64 65 typedef void (*gtaskqueue_enqueue_fn)(void *context); 66 67 struct gtaskqueue { 68 STAILQ_HEAD(, gtask) tq_queue; 69 LIST_HEAD(, gtaskqueue_busy) tq_active; 70 u_int tq_seq; 71 int tq_callouts; 72 struct mtx_padalign tq_mutex; 73 gtaskqueue_enqueue_fn tq_enqueue; 74 void *tq_context; 75 char *tq_name; 76 struct thread **tq_threads; 77 int tq_tcount; 78 int tq_spin; 79 int tq_flags; 80 taskqueue_callback_fn tq_callbacks[TASKQUEUE_NUM_CALLBACKS]; 81 void *tq_cb_contexts[TASKQUEUE_NUM_CALLBACKS]; 82 }; 83 84 #define TQ_FLAGS_ACTIVE (1 << 0) 85 #define TQ_FLAGS_BLOCKED (1 << 1) 86 #define TQ_FLAGS_UNLOCKED_ENQUEUE (1 << 2) 87 88 #define DT_CALLOUT_ARMED (1 << 0) 89 90 #define TQ_LOCK(tq) \ 91 do { \ 92 if ((tq)->tq_spin) \ 93 mtx_lock_spin(&(tq)->tq_mutex); \ 94 else \ 95 mtx_lock(&(tq)->tq_mutex); \ 96 } while (0) 97 #define TQ_ASSERT_LOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_OWNED) 98 99 #define TQ_UNLOCK(tq) \ 100 do { \ 101 if ((tq)->tq_spin) \ 102 mtx_unlock_spin(&(tq)->tq_mutex); \ 103 else \ 104 mtx_unlock(&(tq)->tq_mutex); \ 105 } while (0) 106 #define TQ_ASSERT_UNLOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_NOTOWNED) 107 108 #ifdef INVARIANTS 109 static void 110 gtask_dump(struct gtask *gtask) 111 { 112 printf("gtask: %p ta_flags=%x ta_priority=%d ta_func=%p ta_context=%p\n", 113 gtask, gtask->ta_flags, gtask->ta_priority, gtask->ta_func, gtask->ta_context); 114 } 115 #endif 116 117 static __inline int 118 TQ_SLEEP(struct gtaskqueue *tq, void *p, const char *wm) 119 { 120 if (tq->tq_spin) 121 return (msleep_spin(p, (struct mtx *)&tq->tq_mutex, wm, 0)); 122 return (msleep(p, &tq->tq_mutex, 0, wm, 0)); 123 } 124 125 static struct gtaskqueue * 126 _gtaskqueue_create(const char *name, int mflags, 127 taskqueue_enqueue_fn enqueue, void *context, 128 int mtxflags, const char *mtxname __unused) 129 { 130 struct gtaskqueue *queue; 131 char *tq_name; 132 133 tq_name = malloc(TASKQUEUE_NAMELEN, M_GTASKQUEUE, mflags | M_ZERO); 134 if (!tq_name) 135 return (NULL); 136 137 snprintf(tq_name, TASKQUEUE_NAMELEN, "%s", (name) ? name : "taskqueue"); 138 139 queue = malloc(sizeof(struct gtaskqueue), M_GTASKQUEUE, mflags | M_ZERO); 140 if (!queue) { 141 free(tq_name, M_GTASKQUEUE); 142 return (NULL); 143 } 144 145 STAILQ_INIT(&queue->tq_queue); 146 LIST_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 == gtaskqueue_thread_enqueue) 153 queue->tq_flags |= TQ_FLAGS_UNLOCKED_ENQUEUE; 154 mtx_init(&queue->tq_mutex, tq_name, NULL, mtxflags); 155 156 return (queue); 157 } 158 159 160 /* 161 * Signal a taskqueue thread to terminate. 162 */ 163 static void 164 gtaskqueue_terminate(struct thread **pp, struct gtaskqueue *tq) 165 { 166 167 while (tq->tq_tcount > 0 || tq->tq_callouts > 0) { 168 wakeup(tq); 169 TQ_SLEEP(tq, pp, "gtq_destroy"); 170 } 171 } 172 173 static void 174 gtaskqueue_free(struct gtaskqueue *queue) 175 { 176 177 TQ_LOCK(queue); 178 queue->tq_flags &= ~TQ_FLAGS_ACTIVE; 179 gtaskqueue_terminate(queue->tq_threads, queue); 180 KASSERT(LIST_EMPTY(&queue->tq_active), ("Tasks still running?")); 181 KASSERT(queue->tq_callouts == 0, ("Armed timeout tasks")); 182 mtx_destroy(&queue->tq_mutex); 183 free(queue->tq_threads, M_GTASKQUEUE); 184 free(queue->tq_name, M_GTASKQUEUE); 185 free(queue, M_GTASKQUEUE); 186 } 187 188 /* 189 * Wait for all to complete, then prevent it from being enqueued 190 */ 191 void 192 grouptask_block(struct grouptask *grouptask) 193 { 194 struct gtaskqueue *queue = grouptask->gt_taskqueue; 195 struct gtask *gtask = &grouptask->gt_task; 196 197 #ifdef INVARIANTS 198 if (queue == NULL) { 199 gtask_dump(gtask); 200 panic("queue == NULL"); 201 } 202 #endif 203 TQ_LOCK(queue); 204 gtask->ta_flags |= TASK_NOENQUEUE; 205 gtaskqueue_drain_locked(queue, gtask); 206 TQ_UNLOCK(queue); 207 } 208 209 void 210 grouptask_unblock(struct grouptask *grouptask) 211 { 212 struct gtaskqueue *queue = grouptask->gt_taskqueue; 213 struct gtask *gtask = &grouptask->gt_task; 214 215 #ifdef INVARIANTS 216 if (queue == NULL) { 217 gtask_dump(gtask); 218 panic("queue == NULL"); 219 } 220 #endif 221 TQ_LOCK(queue); 222 gtask->ta_flags &= ~TASK_NOENQUEUE; 223 TQ_UNLOCK(queue); 224 } 225 226 int 227 grouptaskqueue_enqueue(struct gtaskqueue *queue, struct gtask *gtask) 228 { 229 #ifdef INVARIANTS 230 if (queue == NULL) { 231 gtask_dump(gtask); 232 panic("queue == NULL"); 233 } 234 #endif 235 TQ_LOCK(queue); 236 if (gtask->ta_flags & TASK_ENQUEUED) { 237 TQ_UNLOCK(queue); 238 return (0); 239 } 240 if (gtask->ta_flags & TASK_NOENQUEUE) { 241 TQ_UNLOCK(queue); 242 return (EAGAIN); 243 } 244 STAILQ_INSERT_TAIL(&queue->tq_queue, gtask, ta_link); 245 gtask->ta_flags |= TASK_ENQUEUED; 246 TQ_UNLOCK(queue); 247 if ((queue->tq_flags & TQ_FLAGS_BLOCKED) == 0) 248 queue->tq_enqueue(queue->tq_context); 249 return (0); 250 } 251 252 static void 253 gtaskqueue_task_nop_fn(void *context) 254 { 255 } 256 257 /* 258 * Block until all currently queued tasks in this taskqueue 259 * have begun execution. Tasks queued during execution of 260 * this function are ignored. 261 */ 262 static void 263 gtaskqueue_drain_tq_queue(struct gtaskqueue *queue) 264 { 265 struct gtask t_barrier; 266 267 if (STAILQ_EMPTY(&queue->tq_queue)) 268 return; 269 270 /* 271 * Enqueue our barrier after all current tasks, but with 272 * the highest priority so that newly queued tasks cannot 273 * pass it. Because of the high priority, we can not use 274 * taskqueue_enqueue_locked directly (which drops the lock 275 * anyway) so just insert it at tail while we have the 276 * queue lock. 277 */ 278 GTASK_INIT(&t_barrier, 0, USHRT_MAX, gtaskqueue_task_nop_fn, &t_barrier); 279 STAILQ_INSERT_TAIL(&queue->tq_queue, &t_barrier, ta_link); 280 t_barrier.ta_flags |= TASK_ENQUEUED; 281 282 /* 283 * Once the barrier has executed, all previously queued tasks 284 * have completed or are currently executing. 285 */ 286 while (t_barrier.ta_flags & TASK_ENQUEUED) 287 TQ_SLEEP(queue, &t_barrier, "gtq_qdrain"); 288 } 289 290 /* 291 * Block until all currently executing tasks for this taskqueue 292 * complete. Tasks that begin execution during the execution 293 * of this function are ignored. 294 */ 295 static void 296 gtaskqueue_drain_tq_active(struct gtaskqueue *queue) 297 { 298 struct gtaskqueue_busy *tb; 299 u_int seq; 300 301 if (LIST_EMPTY(&queue->tq_active)) 302 return; 303 304 /* Block taskq_terminate().*/ 305 queue->tq_callouts++; 306 307 /* Wait for any active task with sequence from the past. */ 308 seq = queue->tq_seq; 309 restart: 310 LIST_FOREACH(tb, &queue->tq_active, tb_link) { 311 if ((int)(tb->tb_seq - seq) <= 0) { 312 TQ_SLEEP(queue, tb->tb_running, "gtq_adrain"); 313 goto restart; 314 } 315 } 316 317 /* Release taskqueue_terminate(). */ 318 queue->tq_callouts--; 319 if ((queue->tq_flags & TQ_FLAGS_ACTIVE) == 0) 320 wakeup_one(queue->tq_threads); 321 } 322 323 void 324 gtaskqueue_block(struct gtaskqueue *queue) 325 { 326 327 TQ_LOCK(queue); 328 queue->tq_flags |= TQ_FLAGS_BLOCKED; 329 TQ_UNLOCK(queue); 330 } 331 332 void 333 gtaskqueue_unblock(struct gtaskqueue *queue) 334 { 335 336 TQ_LOCK(queue); 337 queue->tq_flags &= ~TQ_FLAGS_BLOCKED; 338 if (!STAILQ_EMPTY(&queue->tq_queue)) 339 queue->tq_enqueue(queue->tq_context); 340 TQ_UNLOCK(queue); 341 } 342 343 static void 344 gtaskqueue_run_locked(struct gtaskqueue *queue) 345 { 346 struct gtaskqueue_busy tb; 347 struct gtask *gtask; 348 349 KASSERT(queue != NULL, ("tq is NULL")); 350 TQ_ASSERT_LOCKED(queue); 351 tb.tb_running = NULL; 352 LIST_INSERT_HEAD(&queue->tq_active, &tb, tb_link); 353 354 while ((gtask = STAILQ_FIRST(&queue->tq_queue)) != NULL) { 355 STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link); 356 gtask->ta_flags &= ~TASK_ENQUEUED; 357 tb.tb_running = gtask; 358 tb.tb_seq = ++queue->tq_seq; 359 TQ_UNLOCK(queue); 360 361 KASSERT(gtask->ta_func != NULL, ("task->ta_func is NULL")); 362 gtask->ta_func(gtask->ta_context); 363 364 TQ_LOCK(queue); 365 wakeup(gtask); 366 } 367 LIST_REMOVE(&tb, tb_link); 368 } 369 370 static int 371 task_is_running(struct gtaskqueue *queue, struct gtask *gtask) 372 { 373 struct gtaskqueue_busy *tb; 374 375 TQ_ASSERT_LOCKED(queue); 376 LIST_FOREACH(tb, &queue->tq_active, tb_link) { 377 if (tb->tb_running == gtask) 378 return (1); 379 } 380 return (0); 381 } 382 383 static int 384 gtaskqueue_cancel_locked(struct gtaskqueue *queue, struct gtask *gtask) 385 { 386 387 if (gtask->ta_flags & TASK_ENQUEUED) 388 STAILQ_REMOVE(&queue->tq_queue, gtask, gtask, ta_link); 389 gtask->ta_flags &= ~TASK_ENQUEUED; 390 return (task_is_running(queue, gtask) ? EBUSY : 0); 391 } 392 393 int 394 gtaskqueue_cancel(struct gtaskqueue *queue, struct gtask *gtask) 395 { 396 int error; 397 398 TQ_LOCK(queue); 399 error = gtaskqueue_cancel_locked(queue, gtask); 400 TQ_UNLOCK(queue); 401 402 return (error); 403 } 404 405 static void 406 gtaskqueue_drain_locked(struct gtaskqueue *queue, struct gtask *gtask) 407 { 408 while ((gtask->ta_flags & TASK_ENQUEUED) || task_is_running(queue, gtask)) 409 TQ_SLEEP(queue, gtask, "gtq_drain"); 410 } 411 412 void 413 gtaskqueue_drain(struct gtaskqueue *queue, struct gtask *gtask) 414 { 415 416 if (!queue->tq_spin) 417 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 418 419 TQ_LOCK(queue); 420 gtaskqueue_drain_locked(queue, gtask); 421 TQ_UNLOCK(queue); 422 } 423 424 void 425 gtaskqueue_drain_all(struct gtaskqueue *queue) 426 { 427 428 if (!queue->tq_spin) 429 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 430 431 TQ_LOCK(queue); 432 gtaskqueue_drain_tq_queue(queue); 433 gtaskqueue_drain_tq_active(queue); 434 TQ_UNLOCK(queue); 435 } 436 437 static int 438 _gtaskqueue_start_threads(struct gtaskqueue **tqp, int count, int pri, 439 cpuset_t *mask, const char *name, va_list ap) 440 { 441 char ktname[MAXCOMLEN + 1]; 442 struct thread *td; 443 struct gtaskqueue *tq; 444 int i, error; 445 446 if (count <= 0) 447 return (EINVAL); 448 449 vsnprintf(ktname, sizeof(ktname), name, ap); 450 tq = *tqp; 451 452 tq->tq_threads = malloc(sizeof(struct thread *) * count, M_GTASKQUEUE, 453 M_NOWAIT | M_ZERO); 454 if (tq->tq_threads == NULL) { 455 printf("%s: no memory for %s threads\n", __func__, ktname); 456 return (ENOMEM); 457 } 458 459 for (i = 0; i < count; i++) { 460 if (count == 1) 461 error = kthread_add(gtaskqueue_thread_loop, tqp, NULL, 462 &tq->tq_threads[i], RFSTOPPED, 0, "%s", ktname); 463 else 464 error = kthread_add(gtaskqueue_thread_loop, tqp, NULL, 465 &tq->tq_threads[i], RFSTOPPED, 0, 466 "%s_%d", ktname, i); 467 if (error) { 468 /* should be ok to continue, taskqueue_free will dtrt */ 469 printf("%s: kthread_add(%s): error %d", __func__, 470 ktname, error); 471 tq->tq_threads[i] = NULL; /* paranoid */ 472 } else 473 tq->tq_tcount++; 474 } 475 for (i = 0; i < count; i++) { 476 if (tq->tq_threads[i] == NULL) 477 continue; 478 td = tq->tq_threads[i]; 479 if (mask) { 480 error = cpuset_setthread(td->td_tid, mask); 481 /* 482 * Failing to pin is rarely an actual fatal error; 483 * it'll just affect performance. 484 */ 485 if (error) 486 printf("%s: curthread=%llu: can't pin; " 487 "error=%d\n", 488 __func__, 489 (unsigned long long) td->td_tid, 490 error); 491 } 492 thread_lock(td); 493 sched_prio(td, pri); 494 sched_add(td, SRQ_BORING); 495 } 496 497 return (0); 498 } 499 500 static int 501 gtaskqueue_start_threads(struct gtaskqueue **tqp, int count, int pri, 502 const char *name, ...) 503 { 504 va_list ap; 505 int error; 506 507 va_start(ap, name); 508 error = _gtaskqueue_start_threads(tqp, count, pri, NULL, name, ap); 509 va_end(ap); 510 return (error); 511 } 512 513 static inline void 514 gtaskqueue_run_callback(struct gtaskqueue *tq, 515 enum taskqueue_callback_type cb_type) 516 { 517 taskqueue_callback_fn tq_callback; 518 519 TQ_ASSERT_UNLOCKED(tq); 520 tq_callback = tq->tq_callbacks[cb_type]; 521 if (tq_callback != NULL) 522 tq_callback(tq->tq_cb_contexts[cb_type]); 523 } 524 525 static void 526 gtaskqueue_thread_loop(void *arg) 527 { 528 struct gtaskqueue **tqp, *tq; 529 530 tqp = arg; 531 tq = *tqp; 532 gtaskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_INIT); 533 TQ_LOCK(tq); 534 while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) { 535 /* XXX ? */ 536 gtaskqueue_run_locked(tq); 537 /* 538 * Because taskqueue_run() can drop tq_mutex, we need to 539 * check if the TQ_FLAGS_ACTIVE flag wasn't removed in the 540 * meantime, which means we missed a wakeup. 541 */ 542 if ((tq->tq_flags & TQ_FLAGS_ACTIVE) == 0) 543 break; 544 TQ_SLEEP(tq, tq, "-"); 545 } 546 gtaskqueue_run_locked(tq); 547 /* 548 * This thread is on its way out, so just drop the lock temporarily 549 * in order to call the shutdown callback. This allows the callback 550 * to look at the taskqueue, even just before it dies. 551 */ 552 TQ_UNLOCK(tq); 553 gtaskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN); 554 TQ_LOCK(tq); 555 556 /* rendezvous with thread that asked us to terminate */ 557 tq->tq_tcount--; 558 wakeup_one(tq->tq_threads); 559 TQ_UNLOCK(tq); 560 kthread_exit(); 561 } 562 563 static void 564 gtaskqueue_thread_enqueue(void *context) 565 { 566 struct gtaskqueue **tqp, *tq; 567 568 tqp = context; 569 tq = *tqp; 570 wakeup_any(tq); 571 } 572 573 574 static struct gtaskqueue * 575 gtaskqueue_create_fast(const char *name, int mflags, 576 taskqueue_enqueue_fn enqueue, void *context) 577 { 578 return _gtaskqueue_create(name, mflags, enqueue, context, 579 MTX_SPIN, "fast_taskqueue"); 580 } 581 582 583 struct taskqgroup_cpu { 584 LIST_HEAD(, grouptask) tgc_tasks; 585 struct gtaskqueue *tgc_taskq; 586 int tgc_cnt; 587 int tgc_cpu; 588 }; 589 590 struct taskqgroup { 591 struct taskqgroup_cpu tqg_queue[MAXCPU]; 592 struct mtx tqg_lock; 593 const char * tqg_name; 594 int tqg_adjusting; 595 int tqg_stride; 596 int tqg_cnt; 597 }; 598 599 struct taskq_bind_task { 600 struct gtask bt_task; 601 int bt_cpuid; 602 }; 603 604 static void 605 taskqgroup_cpu_create(struct taskqgroup *qgroup, int idx, int cpu) 606 { 607 struct taskqgroup_cpu *qcpu; 608 609 qcpu = &qgroup->tqg_queue[idx]; 610 LIST_INIT(&qcpu->tgc_tasks); 611 qcpu->tgc_taskq = gtaskqueue_create_fast(NULL, M_WAITOK, 612 taskqueue_thread_enqueue, &qcpu->tgc_taskq); 613 gtaskqueue_start_threads(&qcpu->tgc_taskq, 1, PI_SOFT, 614 "%s_%d", qgroup->tqg_name, idx); 615 qcpu->tgc_cpu = cpu; 616 } 617 618 static void 619 taskqgroup_cpu_remove(struct taskqgroup *qgroup, int idx) 620 { 621 622 gtaskqueue_free(qgroup->tqg_queue[idx].tgc_taskq); 623 } 624 625 /* 626 * Find the taskq with least # of tasks that doesn't currently have any 627 * other queues from the uniq identifier. 628 */ 629 static int 630 taskqgroup_find(struct taskqgroup *qgroup, void *uniq) 631 { 632 struct grouptask *n; 633 int i, idx, mincnt; 634 int strict; 635 636 mtx_assert(&qgroup->tqg_lock, MA_OWNED); 637 if (qgroup->tqg_cnt == 0) 638 return (0); 639 idx = -1; 640 mincnt = INT_MAX; 641 /* 642 * Two passes; First scan for a queue with the least tasks that 643 * does not already service this uniq id. If that fails simply find 644 * the queue with the least total tasks; 645 */ 646 for (strict = 1; mincnt == INT_MAX; strict = 0) { 647 for (i = 0; i < qgroup->tqg_cnt; i++) { 648 if (qgroup->tqg_queue[i].tgc_cnt > mincnt) 649 continue; 650 if (strict) { 651 LIST_FOREACH(n, 652 &qgroup->tqg_queue[i].tgc_tasks, gt_list) 653 if (n->gt_uniq == uniq) 654 break; 655 if (n != NULL) 656 continue; 657 } 658 mincnt = qgroup->tqg_queue[i].tgc_cnt; 659 idx = i; 660 } 661 } 662 if (idx == -1) 663 panic("%s: failed to pick a qid.", __func__); 664 665 return (idx); 666 } 667 668 /* 669 * smp_started is unusable since it is not set for UP kernels or even for 670 * SMP kernels when there is 1 CPU. This is usually handled by adding a 671 * (mp_ncpus == 1) test, but that would be broken here since we need to 672 * to synchronize with the SI_SUB_SMP ordering. Even in the pure SMP case 673 * smp_started only gives a fuzzy ordering relative to SI_SUB_SMP. 674 * 675 * So maintain our own flag. It must be set after all CPUs are started 676 * and before SI_SUB_SMP:SI_ORDER_ANY so that the SYSINIT for delayed 677 * adjustment is properly delayed. SI_ORDER_FOURTH is clearly before 678 * SI_ORDER_ANY and unclearly after the CPUs are started. It would be 679 * simpler for adjustment to pass a flag indicating if it is delayed. 680 */ 681 682 static int tqg_smp_started; 683 684 static void 685 tqg_record_smp_started(void *arg) 686 { 687 tqg_smp_started = 1; 688 } 689 690 SYSINIT(tqg_record_smp_started, SI_SUB_SMP, SI_ORDER_FOURTH, 691 tqg_record_smp_started, NULL); 692 693 void 694 taskqgroup_attach(struct taskqgroup *qgroup, struct grouptask *gtask, 695 void *uniq, device_t dev, struct resource *irq, const char *name) 696 { 697 int cpu, qid, error; 698 699 gtask->gt_uniq = uniq; 700 snprintf(gtask->gt_name, GROUPTASK_NAMELEN, "%s", name ? name : "grouptask"); 701 gtask->gt_dev = dev; 702 gtask->gt_irq = irq; 703 gtask->gt_cpu = -1; 704 mtx_lock(&qgroup->tqg_lock); 705 qid = taskqgroup_find(qgroup, uniq); 706 qgroup->tqg_queue[qid].tgc_cnt++; 707 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, gt_list); 708 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 709 if (dev != NULL && irq != NULL && tqg_smp_started) { 710 cpu = qgroup->tqg_queue[qid].tgc_cpu; 711 gtask->gt_cpu = cpu; 712 mtx_unlock(&qgroup->tqg_lock); 713 error = bus_bind_intr(dev, irq, cpu); 714 if (error) 715 printf("%s: binding interrupt failed for %s: %d\n", 716 __func__, gtask->gt_name, error); 717 } else 718 mtx_unlock(&qgroup->tqg_lock); 719 } 720 721 static void 722 taskqgroup_attach_deferred(struct taskqgroup *qgroup, struct grouptask *gtask) 723 { 724 int qid, cpu, error; 725 726 mtx_lock(&qgroup->tqg_lock); 727 qid = taskqgroup_find(qgroup, gtask->gt_uniq); 728 cpu = qgroup->tqg_queue[qid].tgc_cpu; 729 if (gtask->gt_dev != NULL && gtask->gt_irq != NULL) { 730 mtx_unlock(&qgroup->tqg_lock); 731 error = bus_bind_intr(gtask->gt_dev, gtask->gt_irq, cpu); 732 mtx_lock(&qgroup->tqg_lock); 733 if (error) 734 printf("%s: binding interrupt failed for %s: %d\n", 735 __func__, gtask->gt_name, error); 736 737 } 738 qgroup->tqg_queue[qid].tgc_cnt++; 739 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, gt_list); 740 MPASS(qgroup->tqg_queue[qid].tgc_taskq != NULL); 741 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 742 mtx_unlock(&qgroup->tqg_lock); 743 } 744 745 int 746 taskqgroup_attach_cpu(struct taskqgroup *qgroup, struct grouptask *gtask, 747 void *uniq, int cpu, device_t dev, struct resource *irq, const char *name) 748 { 749 int i, qid, error; 750 751 qid = -1; 752 gtask->gt_uniq = uniq; 753 snprintf(gtask->gt_name, GROUPTASK_NAMELEN, "%s", name ? name : "grouptask"); 754 gtask->gt_dev = dev; 755 gtask->gt_irq = irq; 756 gtask->gt_cpu = cpu; 757 mtx_lock(&qgroup->tqg_lock); 758 if (tqg_smp_started) { 759 for (i = 0; i < qgroup->tqg_cnt; i++) 760 if (qgroup->tqg_queue[i].tgc_cpu == cpu) { 761 qid = i; 762 break; 763 } 764 if (qid == -1) { 765 mtx_unlock(&qgroup->tqg_lock); 766 printf("%s: qid not found for %s cpu=%d\n", __func__, gtask->gt_name, cpu); 767 return (EINVAL); 768 } 769 } else 770 qid = 0; 771 qgroup->tqg_queue[qid].tgc_cnt++; 772 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, gt_list); 773 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 774 cpu = qgroup->tqg_queue[qid].tgc_cpu; 775 mtx_unlock(&qgroup->tqg_lock); 776 777 if (dev != NULL && irq != NULL && tqg_smp_started) { 778 error = bus_bind_intr(dev, irq, cpu); 779 if (error) 780 printf("%s: binding interrupt failed for %s: %d\n", 781 __func__, gtask->gt_name, error); 782 } 783 return (0); 784 } 785 786 static int 787 taskqgroup_attach_cpu_deferred(struct taskqgroup *qgroup, struct grouptask *gtask) 788 { 789 device_t dev; 790 struct resource *irq; 791 int cpu, error, i, qid; 792 793 qid = -1; 794 dev = gtask->gt_dev; 795 irq = gtask->gt_irq; 796 cpu = gtask->gt_cpu; 797 MPASS(tqg_smp_started); 798 mtx_lock(&qgroup->tqg_lock); 799 for (i = 0; i < qgroup->tqg_cnt; i++) 800 if (qgroup->tqg_queue[i].tgc_cpu == cpu) { 801 qid = i; 802 break; 803 } 804 if (qid == -1) { 805 mtx_unlock(&qgroup->tqg_lock); 806 printf("%s: qid not found for %s cpu=%d\n", __func__, gtask->gt_name, cpu); 807 return (EINVAL); 808 } 809 qgroup->tqg_queue[qid].tgc_cnt++; 810 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, gt_list); 811 MPASS(qgroup->tqg_queue[qid].tgc_taskq != NULL); 812 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 813 mtx_unlock(&qgroup->tqg_lock); 814 815 if (dev != NULL && irq != NULL) { 816 error = bus_bind_intr(dev, irq, cpu); 817 if (error) 818 printf("%s: binding interrupt failed for %s: %d\n", 819 __func__, gtask->gt_name, error); 820 } 821 return (0); 822 } 823 824 void 825 taskqgroup_detach(struct taskqgroup *qgroup, struct grouptask *gtask) 826 { 827 int i; 828 829 grouptask_block(gtask); 830 mtx_lock(&qgroup->tqg_lock); 831 for (i = 0; i < qgroup->tqg_cnt; i++) 832 if (qgroup->tqg_queue[i].tgc_taskq == gtask->gt_taskqueue) 833 break; 834 if (i == qgroup->tqg_cnt) 835 panic("%s: task %s not in group", __func__, gtask->gt_name); 836 qgroup->tqg_queue[i].tgc_cnt--; 837 LIST_REMOVE(gtask, gt_list); 838 mtx_unlock(&qgroup->tqg_lock); 839 gtask->gt_taskqueue = NULL; 840 gtask->gt_task.ta_flags &= ~TASK_NOENQUEUE; 841 } 842 843 static void 844 taskqgroup_binder(void *ctx) 845 { 846 struct taskq_bind_task *gtask = (struct taskq_bind_task *)ctx; 847 cpuset_t mask; 848 int error; 849 850 CPU_ZERO(&mask); 851 CPU_SET(gtask->bt_cpuid, &mask); 852 error = cpuset_setthread(curthread->td_tid, &mask); 853 thread_lock(curthread); 854 sched_bind(curthread, gtask->bt_cpuid); 855 thread_unlock(curthread); 856 857 if (error) 858 printf("%s: binding curthread failed: %d\n", __func__, error); 859 free(gtask, M_DEVBUF); 860 } 861 862 static void 863 taskqgroup_bind(struct taskqgroup *qgroup) 864 { 865 struct taskq_bind_task *gtask; 866 int i; 867 868 /* 869 * Bind taskqueue threads to specific CPUs, if they have been assigned 870 * one. 871 */ 872 if (qgroup->tqg_cnt == 1) 873 return; 874 875 for (i = 0; i < qgroup->tqg_cnt; i++) { 876 gtask = malloc(sizeof (*gtask), M_DEVBUF, M_WAITOK); 877 GTASK_INIT(>ask->bt_task, 0, 0, taskqgroup_binder, gtask); 878 gtask->bt_cpuid = qgroup->tqg_queue[i].tgc_cpu; 879 grouptaskqueue_enqueue(qgroup->tqg_queue[i].tgc_taskq, 880 >ask->bt_task); 881 } 882 } 883 884 static void 885 taskqgroup_config_init(void *arg) 886 { 887 struct taskqgroup *qgroup = qgroup_config; 888 LIST_HEAD(, grouptask) gtask_head = LIST_HEAD_INITIALIZER(NULL); 889 890 LIST_SWAP(>ask_head, &qgroup->tqg_queue[0].tgc_tasks, 891 grouptask, gt_list); 892 qgroup->tqg_queue[0].tgc_cnt = 0; 893 taskqgroup_cpu_create(qgroup, 0, 0); 894 895 qgroup->tqg_cnt = 1; 896 qgroup->tqg_stride = 1; 897 } 898 899 SYSINIT(taskqgroup_config_init, SI_SUB_TASKQ, SI_ORDER_SECOND, 900 taskqgroup_config_init, NULL); 901 902 static int 903 _taskqgroup_adjust(struct taskqgroup *qgroup, int cnt, int stride) 904 { 905 LIST_HEAD(, grouptask) gtask_head = LIST_HEAD_INITIALIZER(NULL); 906 struct grouptask *gtask; 907 int i, k, old_cnt, old_cpu, cpu; 908 909 mtx_assert(&qgroup->tqg_lock, MA_OWNED); 910 911 if (cnt < 1 || cnt * stride > mp_ncpus || !tqg_smp_started) { 912 printf("%s: failed cnt: %d stride: %d " 913 "mp_ncpus: %d tqg_smp_started: %d\n", 914 __func__, cnt, stride, mp_ncpus, tqg_smp_started); 915 return (EINVAL); 916 } 917 if (qgroup->tqg_adjusting) { 918 printf("%s failed: adjusting\n", __func__); 919 return (EBUSY); 920 } 921 qgroup->tqg_adjusting = 1; 922 old_cnt = qgroup->tqg_cnt; 923 old_cpu = 0; 924 if (old_cnt < cnt) 925 old_cpu = qgroup->tqg_queue[old_cnt].tgc_cpu; 926 mtx_unlock(&qgroup->tqg_lock); 927 /* 928 * Set up queue for tasks added before boot. 929 */ 930 if (old_cnt == 0) { 931 LIST_SWAP(>ask_head, &qgroup->tqg_queue[0].tgc_tasks, 932 grouptask, gt_list); 933 qgroup->tqg_queue[0].tgc_cnt = 0; 934 } 935 936 /* 937 * If new taskq threads have been added. 938 */ 939 cpu = old_cpu; 940 for (i = old_cnt; i < cnt; i++) { 941 taskqgroup_cpu_create(qgroup, i, cpu); 942 943 for (k = 0; k < stride; k++) 944 cpu = CPU_NEXT(cpu); 945 } 946 mtx_lock(&qgroup->tqg_lock); 947 qgroup->tqg_cnt = cnt; 948 qgroup->tqg_stride = stride; 949 950 /* 951 * Adjust drivers to use new taskqs. 952 */ 953 for (i = 0; i < old_cnt; i++) { 954 while ((gtask = LIST_FIRST(&qgroup->tqg_queue[i].tgc_tasks))) { 955 LIST_REMOVE(gtask, gt_list); 956 qgroup->tqg_queue[i].tgc_cnt--; 957 LIST_INSERT_HEAD(>ask_head, gtask, gt_list); 958 } 959 } 960 mtx_unlock(&qgroup->tqg_lock); 961 962 while ((gtask = LIST_FIRST(>ask_head))) { 963 LIST_REMOVE(gtask, gt_list); 964 if (gtask->gt_cpu == -1) 965 taskqgroup_attach_deferred(qgroup, gtask); 966 else if (taskqgroup_attach_cpu_deferred(qgroup, gtask)) 967 taskqgroup_attach_deferred(qgroup, gtask); 968 } 969 970 #ifdef INVARIANTS 971 mtx_lock(&qgroup->tqg_lock); 972 for (i = 0; i < qgroup->tqg_cnt; i++) { 973 MPASS(qgroup->tqg_queue[i].tgc_taskq != NULL); 974 LIST_FOREACH(gtask, &qgroup->tqg_queue[i].tgc_tasks, gt_list) 975 MPASS(gtask->gt_taskqueue != NULL); 976 } 977 mtx_unlock(&qgroup->tqg_lock); 978 #endif 979 /* 980 * If taskq thread count has been reduced. 981 */ 982 for (i = cnt; i < old_cnt; i++) 983 taskqgroup_cpu_remove(qgroup, i); 984 985 taskqgroup_bind(qgroup); 986 987 mtx_lock(&qgroup->tqg_lock); 988 qgroup->tqg_adjusting = 0; 989 990 return (0); 991 } 992 993 int 994 taskqgroup_adjust(struct taskqgroup *qgroup, int cnt, int stride) 995 { 996 int error; 997 998 mtx_lock(&qgroup->tqg_lock); 999 error = _taskqgroup_adjust(qgroup, cnt, stride); 1000 mtx_unlock(&qgroup->tqg_lock); 1001 1002 return (error); 1003 } 1004 1005 struct taskqgroup * 1006 taskqgroup_create(const char *name) 1007 { 1008 struct taskqgroup *qgroup; 1009 1010 qgroup = malloc(sizeof(*qgroup), M_GTASKQUEUE, M_WAITOK | M_ZERO); 1011 mtx_init(&qgroup->tqg_lock, "taskqgroup", NULL, MTX_DEF); 1012 qgroup->tqg_name = name; 1013 LIST_INIT(&qgroup->tqg_queue[0].tgc_tasks); 1014 1015 return (qgroup); 1016 } 1017 1018 void 1019 taskqgroup_destroy(struct taskqgroup *qgroup) 1020 { 1021 1022 } 1023 1024 void 1025 taskqgroup_config_gtask_init(void *ctx, struct grouptask *gtask, gtask_fn_t *fn, 1026 const char *name) 1027 { 1028 1029 GROUPTASK_INIT(gtask, 0, fn, ctx); 1030 taskqgroup_attach(qgroup_config, gtask, gtask, NULL, NULL, name); 1031 } 1032 1033 void 1034 taskqgroup_config_gtask_deinit(struct grouptask *gtask) 1035 { 1036 1037 taskqgroup_detach(qgroup_config, gtask); 1038 } 1039