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/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/gtaskqueue.h> 48 #include <sys/unistd.h> 49 #include <machine/stdarg.h> 50 51 static MALLOC_DEFINE(M_GTASKQUEUE, "taskqueue", "Task Queues"); 52 static void gtaskqueue_thread_enqueue(void *); 53 static void gtaskqueue_thread_loop(void *arg); 54 55 TASKQGROUP_DEFINE(softirq, mp_ncpus, 1); 56 57 struct gtaskqueue_busy { 58 struct gtask *tb_running; 59 TAILQ_ENTRY(gtaskqueue_busy) tb_link; 60 }; 61 62 static struct gtask * const TB_DRAIN_WAITER = (struct gtask *)0x1; 63 64 struct gtaskqueue { 65 STAILQ_HEAD(, gtask) tq_queue; 66 gtaskqueue_enqueue_fn tq_enqueue; 67 void *tq_context; 68 char *tq_name; 69 TAILQ_HEAD(, gtaskqueue_busy) tq_active; 70 struct mtx tq_mutex; 71 struct thread **tq_threads; 72 int tq_tcount; 73 int tq_spin; 74 int tq_flags; 75 int tq_callouts; 76 taskqueue_callback_fn tq_callbacks[TASKQUEUE_NUM_CALLBACKS]; 77 void *tq_cb_contexts[TASKQUEUE_NUM_CALLBACKS]; 78 }; 79 80 #define TQ_FLAGS_ACTIVE (1 << 0) 81 #define TQ_FLAGS_BLOCKED (1 << 1) 82 #define TQ_FLAGS_UNLOCKED_ENQUEUE (1 << 2) 83 84 #define DT_CALLOUT_ARMED (1 << 0) 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 #ifdef INVARIANTS 105 static void 106 gtask_dump(struct gtask *gtask) 107 { 108 printf("gtask: %p ta_flags=%x ta_priority=%d ta_func=%p ta_context=%p\n", 109 gtask, gtask->ta_flags, gtask->ta_priority, gtask->ta_func, gtask->ta_context); 110 } 111 #endif 112 113 static __inline int 114 TQ_SLEEP(struct gtaskqueue *tq, void *p, struct mtx *m, int pri, const char *wm, 115 int t) 116 { 117 if (tq->tq_spin) 118 return (msleep_spin(p, m, wm, t)); 119 return (msleep(p, m, pri, wm, t)); 120 } 121 122 static struct gtaskqueue * 123 _gtaskqueue_create(const char *name, int mflags, 124 taskqueue_enqueue_fn enqueue, void *context, 125 int mtxflags, const char *mtxname __unused) 126 { 127 struct gtaskqueue *queue; 128 char *tq_name; 129 130 tq_name = malloc(TASKQUEUE_NAMELEN, M_GTASKQUEUE, mflags | M_ZERO); 131 if (!tq_name) 132 return (NULL); 133 134 snprintf(tq_name, TASKQUEUE_NAMELEN, "%s", (name) ? name : "taskqueue"); 135 136 queue = malloc(sizeof(struct gtaskqueue), M_GTASKQUEUE, mflags | M_ZERO); 137 if (!queue) 138 return (NULL); 139 140 STAILQ_INIT(&queue->tq_queue); 141 TAILQ_INIT(&queue->tq_active); 142 queue->tq_enqueue = enqueue; 143 queue->tq_context = context; 144 queue->tq_name = tq_name; 145 queue->tq_spin = (mtxflags & MTX_SPIN) != 0; 146 queue->tq_flags |= TQ_FLAGS_ACTIVE; 147 if (enqueue == gtaskqueue_thread_enqueue) 148 queue->tq_flags |= TQ_FLAGS_UNLOCKED_ENQUEUE; 149 mtx_init(&queue->tq_mutex, tq_name, NULL, mtxflags); 150 151 return (queue); 152 } 153 154 155 /* 156 * Signal a taskqueue thread to terminate. 157 */ 158 static void 159 gtaskqueue_terminate(struct thread **pp, struct gtaskqueue *tq) 160 { 161 162 while (tq->tq_tcount > 0 || tq->tq_callouts > 0) { 163 wakeup(tq); 164 TQ_SLEEP(tq, pp, &tq->tq_mutex, PWAIT, "taskqueue_destroy", 0); 165 } 166 } 167 168 static void 169 gtaskqueue_free(struct gtaskqueue *queue) 170 { 171 172 TQ_LOCK(queue); 173 queue->tq_flags &= ~TQ_FLAGS_ACTIVE; 174 gtaskqueue_terminate(queue->tq_threads, queue); 175 KASSERT(TAILQ_EMPTY(&queue->tq_active), ("Tasks still running?")); 176 KASSERT(queue->tq_callouts == 0, ("Armed timeout tasks")); 177 mtx_destroy(&queue->tq_mutex); 178 free(queue->tq_threads, M_GTASKQUEUE); 179 free(queue->tq_name, M_GTASKQUEUE); 180 free(queue, M_GTASKQUEUE); 181 } 182 183 int 184 grouptaskqueue_enqueue(struct gtaskqueue *queue, struct gtask *gtask) 185 { 186 #ifdef INVARIANTS 187 if (queue == NULL) { 188 gtask_dump(gtask); 189 panic("queue == NULL"); 190 } 191 #endif 192 TQ_LOCK(queue); 193 if (gtask->ta_flags & TASK_ENQUEUED) { 194 TQ_UNLOCK(queue); 195 return (0); 196 } 197 STAILQ_INSERT_TAIL(&queue->tq_queue, gtask, ta_link); 198 gtask->ta_flags |= TASK_ENQUEUED; 199 TQ_UNLOCK(queue); 200 if ((queue->tq_flags & TQ_FLAGS_BLOCKED) == 0) 201 queue->tq_enqueue(queue->tq_context); 202 return (0); 203 } 204 205 static void 206 gtaskqueue_task_nop_fn(void *context) 207 { 208 } 209 210 /* 211 * Block until all currently queued tasks in this taskqueue 212 * have begun execution. Tasks queued during execution of 213 * this function are ignored. 214 */ 215 static void 216 gtaskqueue_drain_tq_queue(struct gtaskqueue *queue) 217 { 218 struct gtask t_barrier; 219 220 if (STAILQ_EMPTY(&queue->tq_queue)) 221 return; 222 223 /* 224 * Enqueue our barrier after all current tasks, but with 225 * the highest priority so that newly queued tasks cannot 226 * pass it. Because of the high priority, we can not use 227 * taskqueue_enqueue_locked directly (which drops the lock 228 * anyway) so just insert it at tail while we have the 229 * queue lock. 230 */ 231 GTASK_INIT(&t_barrier, 0, USHRT_MAX, gtaskqueue_task_nop_fn, &t_barrier); 232 STAILQ_INSERT_TAIL(&queue->tq_queue, &t_barrier, ta_link); 233 t_barrier.ta_flags |= TASK_ENQUEUED; 234 235 /* 236 * Once the barrier has executed, all previously queued tasks 237 * have completed or are currently executing. 238 */ 239 while (t_barrier.ta_flags & TASK_ENQUEUED) 240 TQ_SLEEP(queue, &t_barrier, &queue->tq_mutex, PWAIT, "-", 0); 241 } 242 243 /* 244 * Block until all currently executing tasks for this taskqueue 245 * complete. Tasks that begin execution during the execution 246 * of this function are ignored. 247 */ 248 static void 249 gtaskqueue_drain_tq_active(struct gtaskqueue *queue) 250 { 251 struct gtaskqueue_busy tb_marker, *tb_first; 252 253 if (TAILQ_EMPTY(&queue->tq_active)) 254 return; 255 256 /* Block taskq_terminate().*/ 257 queue->tq_callouts++; 258 259 /* 260 * Wait for all currently executing taskqueue threads 261 * to go idle. 262 */ 263 tb_marker.tb_running = TB_DRAIN_WAITER; 264 TAILQ_INSERT_TAIL(&queue->tq_active, &tb_marker, tb_link); 265 while (TAILQ_FIRST(&queue->tq_active) != &tb_marker) 266 TQ_SLEEP(queue, &tb_marker, &queue->tq_mutex, PWAIT, "-", 0); 267 TAILQ_REMOVE(&queue->tq_active, &tb_marker, tb_link); 268 269 /* 270 * Wakeup any other drain waiter that happened to queue up 271 * without any intervening active thread. 272 */ 273 tb_first = TAILQ_FIRST(&queue->tq_active); 274 if (tb_first != NULL && tb_first->tb_running == TB_DRAIN_WAITER) 275 wakeup(tb_first); 276 277 /* Release taskqueue_terminate(). */ 278 queue->tq_callouts--; 279 if ((queue->tq_flags & TQ_FLAGS_ACTIVE) == 0) 280 wakeup_one(queue->tq_threads); 281 } 282 283 void 284 gtaskqueue_block(struct gtaskqueue *queue) 285 { 286 287 TQ_LOCK(queue); 288 queue->tq_flags |= TQ_FLAGS_BLOCKED; 289 TQ_UNLOCK(queue); 290 } 291 292 void 293 gtaskqueue_unblock(struct gtaskqueue *queue) 294 { 295 296 TQ_LOCK(queue); 297 queue->tq_flags &= ~TQ_FLAGS_BLOCKED; 298 if (!STAILQ_EMPTY(&queue->tq_queue)) 299 queue->tq_enqueue(queue->tq_context); 300 TQ_UNLOCK(queue); 301 } 302 303 static void 304 gtaskqueue_run_locked(struct gtaskqueue *queue) 305 { 306 struct gtaskqueue_busy tb; 307 struct gtaskqueue_busy *tb_first; 308 struct gtask *gtask; 309 310 KASSERT(queue != NULL, ("tq is NULL")); 311 TQ_ASSERT_LOCKED(queue); 312 tb.tb_running = NULL; 313 314 while (STAILQ_FIRST(&queue->tq_queue)) { 315 TAILQ_INSERT_TAIL(&queue->tq_active, &tb, tb_link); 316 317 /* 318 * Carefully remove the first task from the queue and 319 * clear its TASK_ENQUEUED flag 320 */ 321 gtask = STAILQ_FIRST(&queue->tq_queue); 322 KASSERT(gtask != NULL, ("task is NULL")); 323 STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link); 324 gtask->ta_flags &= ~TASK_ENQUEUED; 325 tb.tb_running = gtask; 326 TQ_UNLOCK(queue); 327 328 KASSERT(gtask->ta_func != NULL, ("task->ta_func is NULL")); 329 gtask->ta_func(gtask->ta_context); 330 331 TQ_LOCK(queue); 332 tb.tb_running = NULL; 333 wakeup(gtask); 334 335 TAILQ_REMOVE(&queue->tq_active, &tb, tb_link); 336 tb_first = TAILQ_FIRST(&queue->tq_active); 337 if (tb_first != NULL && 338 tb_first->tb_running == TB_DRAIN_WAITER) 339 wakeup(tb_first); 340 } 341 } 342 343 static int 344 task_is_running(struct gtaskqueue *queue, struct gtask *gtask) 345 { 346 struct gtaskqueue_busy *tb; 347 348 TQ_ASSERT_LOCKED(queue); 349 TAILQ_FOREACH(tb, &queue->tq_active, tb_link) { 350 if (tb->tb_running == gtask) 351 return (1); 352 } 353 return (0); 354 } 355 356 static int 357 gtaskqueue_cancel_locked(struct gtaskqueue *queue, struct gtask *gtask) 358 { 359 360 if (gtask->ta_flags & TASK_ENQUEUED) 361 STAILQ_REMOVE(&queue->tq_queue, gtask, gtask, ta_link); 362 gtask->ta_flags &= ~TASK_ENQUEUED; 363 return (task_is_running(queue, gtask) ? EBUSY : 0); 364 } 365 366 int 367 gtaskqueue_cancel(struct gtaskqueue *queue, struct gtask *gtask) 368 { 369 int error; 370 371 TQ_LOCK(queue); 372 error = gtaskqueue_cancel_locked(queue, gtask); 373 TQ_UNLOCK(queue); 374 375 return (error); 376 } 377 378 void 379 gtaskqueue_drain(struct gtaskqueue *queue, struct gtask *gtask) 380 { 381 382 if (!queue->tq_spin) 383 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 384 385 TQ_LOCK(queue); 386 while ((gtask->ta_flags & TASK_ENQUEUED) || task_is_running(queue, gtask)) 387 TQ_SLEEP(queue, gtask, &queue->tq_mutex, PWAIT, "-", 0); 388 TQ_UNLOCK(queue); 389 } 390 391 void 392 gtaskqueue_drain_all(struct gtaskqueue *queue) 393 { 394 395 if (!queue->tq_spin) 396 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__); 397 398 TQ_LOCK(queue); 399 gtaskqueue_drain_tq_queue(queue); 400 gtaskqueue_drain_tq_active(queue); 401 TQ_UNLOCK(queue); 402 } 403 404 static int 405 _gtaskqueue_start_threads(struct gtaskqueue **tqp, int count, int pri, 406 cpuset_t *mask, const char *name, va_list ap) 407 { 408 char ktname[MAXCOMLEN + 1]; 409 struct thread *td; 410 struct gtaskqueue *tq; 411 int i, error; 412 413 if (count <= 0) 414 return (EINVAL); 415 416 vsnprintf(ktname, sizeof(ktname), name, ap); 417 tq = *tqp; 418 419 tq->tq_threads = malloc(sizeof(struct thread *) * count, M_GTASKQUEUE, 420 M_NOWAIT | M_ZERO); 421 if (tq->tq_threads == NULL) { 422 printf("%s: no memory for %s threads\n", __func__, ktname); 423 return (ENOMEM); 424 } 425 426 for (i = 0; i < count; i++) { 427 if (count == 1) 428 error = kthread_add(gtaskqueue_thread_loop, tqp, NULL, 429 &tq->tq_threads[i], RFSTOPPED, 0, "%s", ktname); 430 else 431 error = kthread_add(gtaskqueue_thread_loop, tqp, NULL, 432 &tq->tq_threads[i], RFSTOPPED, 0, 433 "%s_%d", ktname, i); 434 if (error) { 435 /* should be ok to continue, taskqueue_free will dtrt */ 436 printf("%s: kthread_add(%s): error %d", __func__, 437 ktname, error); 438 tq->tq_threads[i] = NULL; /* paranoid */ 439 } else 440 tq->tq_tcount++; 441 } 442 for (i = 0; i < count; i++) { 443 if (tq->tq_threads[i] == NULL) 444 continue; 445 td = tq->tq_threads[i]; 446 if (mask) { 447 error = cpuset_setthread(td->td_tid, mask); 448 /* 449 * Failing to pin is rarely an actual fatal error; 450 * it'll just affect performance. 451 */ 452 if (error) 453 printf("%s: curthread=%llu: can't pin; " 454 "error=%d\n", 455 __func__, 456 (unsigned long long) td->td_tid, 457 error); 458 } 459 thread_lock(td); 460 sched_prio(td, pri); 461 sched_add(td, SRQ_BORING); 462 thread_unlock(td); 463 } 464 465 return (0); 466 } 467 468 static int 469 gtaskqueue_start_threads(struct gtaskqueue **tqp, int count, int pri, 470 const char *name, ...) 471 { 472 va_list ap; 473 int error; 474 475 va_start(ap, name); 476 error = _gtaskqueue_start_threads(tqp, count, pri, NULL, name, ap); 477 va_end(ap); 478 return (error); 479 } 480 481 static inline void 482 gtaskqueue_run_callback(struct gtaskqueue *tq, 483 enum taskqueue_callback_type cb_type) 484 { 485 taskqueue_callback_fn tq_callback; 486 487 TQ_ASSERT_UNLOCKED(tq); 488 tq_callback = tq->tq_callbacks[cb_type]; 489 if (tq_callback != NULL) 490 tq_callback(tq->tq_cb_contexts[cb_type]); 491 } 492 493 static void 494 gtaskqueue_thread_loop(void *arg) 495 { 496 struct gtaskqueue **tqp, *tq; 497 498 tqp = arg; 499 tq = *tqp; 500 gtaskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_INIT); 501 TQ_LOCK(tq); 502 while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) { 503 /* XXX ? */ 504 gtaskqueue_run_locked(tq); 505 /* 506 * Because taskqueue_run() can drop tq_mutex, we need to 507 * check if the TQ_FLAGS_ACTIVE flag wasn't removed in the 508 * meantime, which means we missed a wakeup. 509 */ 510 if ((tq->tq_flags & TQ_FLAGS_ACTIVE) == 0) 511 break; 512 TQ_SLEEP(tq, tq, &tq->tq_mutex, 0, "-", 0); 513 } 514 gtaskqueue_run_locked(tq); 515 /* 516 * This thread is on its way out, so just drop the lock temporarily 517 * in order to call the shutdown callback. This allows the callback 518 * to look at the taskqueue, even just before it dies. 519 */ 520 TQ_UNLOCK(tq); 521 gtaskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN); 522 TQ_LOCK(tq); 523 524 /* rendezvous with thread that asked us to terminate */ 525 tq->tq_tcount--; 526 wakeup_one(tq->tq_threads); 527 TQ_UNLOCK(tq); 528 kthread_exit(); 529 } 530 531 static void 532 gtaskqueue_thread_enqueue(void *context) 533 { 534 struct gtaskqueue **tqp, *tq; 535 536 tqp = context; 537 tq = *tqp; 538 wakeup_one(tq); 539 } 540 541 542 static struct gtaskqueue * 543 gtaskqueue_create_fast(const char *name, int mflags, 544 taskqueue_enqueue_fn enqueue, void *context) 545 { 546 return _gtaskqueue_create(name, mflags, enqueue, context, 547 MTX_SPIN, "fast_taskqueue"); 548 } 549 550 551 struct taskqgroup_cpu { 552 LIST_HEAD(, grouptask) tgc_tasks; 553 struct gtaskqueue *tgc_taskq; 554 int tgc_cnt; 555 int tgc_cpu; 556 }; 557 558 struct taskqgroup { 559 struct taskqgroup_cpu tqg_queue[MAXCPU]; 560 struct mtx tqg_lock; 561 char * tqg_name; 562 int tqg_adjusting; 563 int tqg_stride; 564 int tqg_cnt; 565 }; 566 567 struct taskq_bind_task { 568 struct gtask bt_task; 569 int bt_cpuid; 570 }; 571 572 static void 573 taskqgroup_cpu_create(struct taskqgroup *qgroup, int idx, int cpu) 574 { 575 struct taskqgroup_cpu *qcpu; 576 577 qcpu = &qgroup->tqg_queue[idx]; 578 LIST_INIT(&qcpu->tgc_tasks); 579 qcpu->tgc_taskq = gtaskqueue_create_fast(NULL, M_WAITOK, 580 taskqueue_thread_enqueue, &qcpu->tgc_taskq); 581 gtaskqueue_start_threads(&qcpu->tgc_taskq, 1, PI_SOFT, 582 "%s_%d", qgroup->tqg_name, idx); 583 qcpu->tgc_cpu = cpu; 584 } 585 586 static void 587 taskqgroup_cpu_remove(struct taskqgroup *qgroup, int idx) 588 { 589 590 gtaskqueue_free(qgroup->tqg_queue[idx].tgc_taskq); 591 } 592 593 /* 594 * Find the taskq with least # of tasks that doesn't currently have any 595 * other queues from the uniq identifier. 596 */ 597 static int 598 taskqgroup_find(struct taskqgroup *qgroup, void *uniq) 599 { 600 struct grouptask *n; 601 int i, idx, mincnt; 602 int strict; 603 604 mtx_assert(&qgroup->tqg_lock, MA_OWNED); 605 if (qgroup->tqg_cnt == 0) 606 return (0); 607 idx = -1; 608 mincnt = INT_MAX; 609 /* 610 * Two passes; First scan for a queue with the least tasks that 611 * does not already service this uniq id. If that fails simply find 612 * the queue with the least total tasks; 613 */ 614 for (strict = 1; mincnt == INT_MAX; strict = 0) { 615 for (i = 0; i < qgroup->tqg_cnt; i++) { 616 if (qgroup->tqg_queue[i].tgc_cnt > mincnt) 617 continue; 618 if (strict) { 619 LIST_FOREACH(n, 620 &qgroup->tqg_queue[i].tgc_tasks, gt_list) 621 if (n->gt_uniq == uniq) 622 break; 623 if (n != NULL) 624 continue; 625 } 626 mincnt = qgroup->tqg_queue[i].tgc_cnt; 627 idx = i; 628 } 629 } 630 if (idx == -1) 631 panic("taskqgroup_find: Failed to pick a qid."); 632 633 return (idx); 634 } 635 636 /* 637 * smp_started is unusable since it is not set for UP kernels or even for 638 * SMP kernels when there is 1 CPU. This is usually handled by adding a 639 * (mp_ncpus == 1) test, but that would be broken here since we need to 640 * to synchronize with the SI_SUB_SMP ordering. Even in the pure SMP case 641 * smp_started only gives a fuzzy ordering relative to SI_SUB_SMP. 642 * 643 * So maintain our own flag. It must be set after all CPUs are started 644 * and before SI_SUB_SMP:SI_ORDER_ANY so that the SYSINIT for delayed 645 * adjustment is properly delayed. SI_ORDER_FOURTH is clearly before 646 * SI_ORDER_ANY and unclearly after the CPUs are started. It would be 647 * simpler for adjustment to pass a flag indicating if it is delayed. 648 */ 649 650 static int tqg_smp_started; 651 652 static void 653 tqg_record_smp_started(void *arg) 654 { 655 tqg_smp_started = 1; 656 } 657 658 SYSINIT(tqg_record_smp_started, SI_SUB_SMP, SI_ORDER_FOURTH, 659 tqg_record_smp_started, NULL); 660 661 void 662 taskqgroup_attach(struct taskqgroup *qgroup, struct grouptask *gtask, 663 void *uniq, int irq, char *name) 664 { 665 cpuset_t mask; 666 int qid; 667 668 gtask->gt_uniq = uniq; 669 gtask->gt_name = name; 670 gtask->gt_irq = irq; 671 gtask->gt_cpu = -1; 672 mtx_lock(&qgroup->tqg_lock); 673 qid = taskqgroup_find(qgroup, uniq); 674 qgroup->tqg_queue[qid].tgc_cnt++; 675 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, gt_list); 676 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 677 if (irq != -1 && tqg_smp_started) { 678 gtask->gt_cpu = qgroup->tqg_queue[qid].tgc_cpu; 679 CPU_ZERO(&mask); 680 CPU_SET(qgroup->tqg_queue[qid].tgc_cpu, &mask); 681 mtx_unlock(&qgroup->tqg_lock); 682 intr_setaffinity(irq, &mask); 683 } else 684 mtx_unlock(&qgroup->tqg_lock); 685 } 686 687 static void 688 taskqgroup_attach_deferred(struct taskqgroup *qgroup, struct grouptask *gtask) 689 { 690 cpuset_t mask; 691 int qid, cpu; 692 693 mtx_lock(&qgroup->tqg_lock); 694 qid = taskqgroup_find(qgroup, gtask->gt_uniq); 695 cpu = qgroup->tqg_queue[qid].tgc_cpu; 696 if (gtask->gt_irq != -1) { 697 mtx_unlock(&qgroup->tqg_lock); 698 699 CPU_ZERO(&mask); 700 CPU_SET(cpu, &mask); 701 intr_setaffinity(gtask->gt_irq, &mask); 702 703 mtx_lock(&qgroup->tqg_lock); 704 } 705 qgroup->tqg_queue[qid].tgc_cnt++; 706 707 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, 708 gt_list); 709 MPASS(qgroup->tqg_queue[qid].tgc_taskq != NULL); 710 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 711 mtx_unlock(&qgroup->tqg_lock); 712 } 713 714 int 715 taskqgroup_attach_cpu(struct taskqgroup *qgroup, struct grouptask *gtask, 716 void *uniq, int cpu, int irq, char *name) 717 { 718 cpuset_t mask; 719 int i, qid; 720 721 qid = -1; 722 gtask->gt_uniq = uniq; 723 gtask->gt_name = name; 724 gtask->gt_irq = irq; 725 gtask->gt_cpu = cpu; 726 mtx_lock(&qgroup->tqg_lock); 727 if (tqg_smp_started) { 728 for (i = 0; i < qgroup->tqg_cnt; i++) 729 if (qgroup->tqg_queue[i].tgc_cpu == cpu) { 730 qid = i; 731 break; 732 } 733 if (qid == -1) { 734 mtx_unlock(&qgroup->tqg_lock); 735 return (EINVAL); 736 } 737 } else 738 qid = 0; 739 qgroup->tqg_queue[qid].tgc_cnt++; 740 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, gt_list); 741 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 742 cpu = qgroup->tqg_queue[qid].tgc_cpu; 743 mtx_unlock(&qgroup->tqg_lock); 744 745 CPU_ZERO(&mask); 746 CPU_SET(cpu, &mask); 747 if (irq != -1 && tqg_smp_started) 748 intr_setaffinity(irq, &mask); 749 return (0); 750 } 751 752 static int 753 taskqgroup_attach_cpu_deferred(struct taskqgroup *qgroup, struct grouptask *gtask) 754 { 755 cpuset_t mask; 756 int i, qid, irq, cpu; 757 758 qid = -1; 759 irq = gtask->gt_irq; 760 cpu = gtask->gt_cpu; 761 MPASS(tqg_smp_started); 762 mtx_lock(&qgroup->tqg_lock); 763 for (i = 0; i < qgroup->tqg_cnt; i++) 764 if (qgroup->tqg_queue[i].tgc_cpu == cpu) { 765 qid = i; 766 break; 767 } 768 if (qid == -1) { 769 mtx_unlock(&qgroup->tqg_lock); 770 return (EINVAL); 771 } 772 qgroup->tqg_queue[qid].tgc_cnt++; 773 LIST_INSERT_HEAD(&qgroup->tqg_queue[qid].tgc_tasks, gtask, gt_list); 774 MPASS(qgroup->tqg_queue[qid].tgc_taskq != NULL); 775 gtask->gt_taskqueue = qgroup->tqg_queue[qid].tgc_taskq; 776 mtx_unlock(&qgroup->tqg_lock); 777 778 CPU_ZERO(&mask); 779 CPU_SET(cpu, &mask); 780 781 if (irq != -1) 782 intr_setaffinity(irq, &mask); 783 return (0); 784 } 785 786 void 787 taskqgroup_detach(struct taskqgroup *qgroup, struct grouptask *gtask) 788 { 789 int i; 790 791 mtx_lock(&qgroup->tqg_lock); 792 for (i = 0; i < qgroup->tqg_cnt; i++) 793 if (qgroup->tqg_queue[i].tgc_taskq == gtask->gt_taskqueue) 794 break; 795 if (i == qgroup->tqg_cnt) 796 panic("taskqgroup_detach: task not in group\n"); 797 qgroup->tqg_queue[i].tgc_cnt--; 798 LIST_REMOVE(gtask, gt_list); 799 mtx_unlock(&qgroup->tqg_lock); 800 gtask->gt_taskqueue = NULL; 801 } 802 803 static void 804 taskqgroup_binder(void *ctx) 805 { 806 struct taskq_bind_task *gtask = (struct taskq_bind_task *)ctx; 807 cpuset_t mask; 808 int error; 809 810 CPU_ZERO(&mask); 811 CPU_SET(gtask->bt_cpuid, &mask); 812 error = cpuset_setthread(curthread->td_tid, &mask); 813 thread_lock(curthread); 814 sched_bind(curthread, gtask->bt_cpuid); 815 thread_unlock(curthread); 816 817 if (error) 818 printf("taskqgroup_binder: setaffinity failed: %d\n", 819 error); 820 free(gtask, M_DEVBUF); 821 } 822 823 static void 824 taskqgroup_bind(struct taskqgroup *qgroup) 825 { 826 struct taskq_bind_task *gtask; 827 int i; 828 829 /* 830 * Bind taskqueue threads to specific CPUs, if they have been assigned 831 * one. 832 */ 833 if (qgroup->tqg_cnt == 1) 834 return; 835 836 for (i = 0; i < qgroup->tqg_cnt; i++) { 837 gtask = malloc(sizeof (*gtask), M_DEVBUF, M_WAITOK); 838 GTASK_INIT(>ask->bt_task, 0, 0, taskqgroup_binder, gtask); 839 gtask->bt_cpuid = qgroup->tqg_queue[i].tgc_cpu; 840 grouptaskqueue_enqueue(qgroup->tqg_queue[i].tgc_taskq, 841 >ask->bt_task); 842 } 843 } 844 845 static int 846 _taskqgroup_adjust(struct taskqgroup *qgroup, int cnt, int stride) 847 { 848 LIST_HEAD(, grouptask) gtask_head = LIST_HEAD_INITIALIZER(NULL); 849 struct grouptask *gtask; 850 int i, k, old_cnt, old_cpu, cpu; 851 852 mtx_assert(&qgroup->tqg_lock, MA_OWNED); 853 854 if (cnt < 1 || cnt * stride > mp_ncpus || !tqg_smp_started) { 855 printf("%s: failed cnt: %d stride: %d " 856 "mp_ncpus: %d tqg_smp_started: %d\n", 857 __func__, cnt, stride, mp_ncpus, tqg_smp_started); 858 return (EINVAL); 859 } 860 if (qgroup->tqg_adjusting) { 861 printf("taskqgroup_adjust failed: adjusting\n"); 862 return (EBUSY); 863 } 864 qgroup->tqg_adjusting = 1; 865 old_cnt = qgroup->tqg_cnt; 866 old_cpu = 0; 867 if (old_cnt < cnt) 868 old_cpu = qgroup->tqg_queue[old_cnt].tgc_cpu; 869 mtx_unlock(&qgroup->tqg_lock); 870 /* 871 * Set up queue for tasks added before boot. 872 */ 873 if (old_cnt == 0) { 874 LIST_SWAP(>ask_head, &qgroup->tqg_queue[0].tgc_tasks, 875 grouptask, gt_list); 876 qgroup->tqg_queue[0].tgc_cnt = 0; 877 } 878 879 /* 880 * If new taskq threads have been added. 881 */ 882 cpu = old_cpu; 883 for (i = old_cnt; i < cnt; i++) { 884 taskqgroup_cpu_create(qgroup, i, cpu); 885 886 for (k = 0; k < stride; k++) 887 cpu = CPU_NEXT(cpu); 888 } 889 mtx_lock(&qgroup->tqg_lock); 890 qgroup->tqg_cnt = cnt; 891 qgroup->tqg_stride = stride; 892 893 /* 894 * Adjust drivers to use new taskqs. 895 */ 896 for (i = 0; i < old_cnt; i++) { 897 while ((gtask = LIST_FIRST(&qgroup->tqg_queue[i].tgc_tasks))) { 898 LIST_REMOVE(gtask, gt_list); 899 qgroup->tqg_queue[i].tgc_cnt--; 900 LIST_INSERT_HEAD(>ask_head, gtask, gt_list); 901 } 902 } 903 mtx_unlock(&qgroup->tqg_lock); 904 905 while ((gtask = LIST_FIRST(>ask_head))) { 906 LIST_REMOVE(gtask, gt_list); 907 if (gtask->gt_cpu == -1) 908 taskqgroup_attach_deferred(qgroup, gtask); 909 else if (taskqgroup_attach_cpu_deferred(qgroup, gtask)) 910 taskqgroup_attach_deferred(qgroup, gtask); 911 } 912 913 #ifdef INVARIANTS 914 mtx_lock(&qgroup->tqg_lock); 915 for (i = 0; i < qgroup->tqg_cnt; i++) { 916 MPASS(qgroup->tqg_queue[i].tgc_taskq != NULL); 917 LIST_FOREACH(gtask, &qgroup->tqg_queue[i].tgc_tasks, gt_list) 918 MPASS(gtask->gt_taskqueue != NULL); 919 } 920 mtx_unlock(&qgroup->tqg_lock); 921 #endif 922 /* 923 * If taskq thread count has been reduced. 924 */ 925 for (i = cnt; i < old_cnt; i++) 926 taskqgroup_cpu_remove(qgroup, i); 927 928 taskqgroup_bind(qgroup); 929 930 mtx_lock(&qgroup->tqg_lock); 931 qgroup->tqg_adjusting = 0; 932 933 return (0); 934 } 935 936 int 937 taskqgroup_adjust(struct taskqgroup *qgroup, int cnt, int stride) 938 { 939 int error; 940 941 mtx_lock(&qgroup->tqg_lock); 942 error = _taskqgroup_adjust(qgroup, cnt, stride); 943 mtx_unlock(&qgroup->tqg_lock); 944 945 return (error); 946 } 947 948 struct taskqgroup * 949 taskqgroup_create(char *name) 950 { 951 struct taskqgroup *qgroup; 952 953 qgroup = malloc(sizeof(*qgroup), M_GTASKQUEUE, M_WAITOK | M_ZERO); 954 mtx_init(&qgroup->tqg_lock, "taskqgroup", NULL, MTX_DEF); 955 qgroup->tqg_name = name; 956 LIST_INIT(&qgroup->tqg_queue[0].tgc_tasks); 957 958 return (qgroup); 959 } 960 961 void 962 taskqgroup_destroy(struct taskqgroup *qgroup) 963 { 964 965 } 966