1 /* 2 * Copyright 2015 Advanced Micro Devices, Inc. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 20 * OTHER DEALINGS IN THE SOFTWARE. 21 * 22 */ 23 24 /** 25 * DOC: Overview 26 * 27 * The GPU scheduler provides entities which allow userspace to push jobs 28 * into software queues which are then scheduled on a hardware run queue. 29 * The software queues have a priority among them. The scheduler selects the entities 30 * from the run queue using a FIFO. The scheduler provides dependency handling 31 * features among jobs. The driver is supposed to provide callback functions for 32 * backend operations to the scheduler like submitting a job to hardware run queue, 33 * returning the dependencies of a job etc. 34 * 35 * The organisation of the scheduler is the following: 36 * 37 * 1. Each hw run queue has one scheduler 38 * 2. Each scheduler has multiple run queues with different priorities 39 * (e.g., HIGH_HW,HIGH_SW, KERNEL, NORMAL) 40 * 3. Each scheduler run queue has a queue of entities to schedule 41 * 4. Entities themselves maintain a queue of jobs that will be scheduled on 42 * the hardware. 43 * 44 * The jobs in a entity are always scheduled in the order that they were pushed. 45 */ 46 47 #include <linux/kthread.h> 48 #include <linux/wait.h> 49 #include <linux/sched.h> 50 #include <linux/completion.h> 51 #include <uapi/linux/sched/types.h> 52 53 #include <drm/drm_print.h> 54 #include <drm/gpu_scheduler.h> 55 #include <drm/spsc_queue.h> 56 57 #define CREATE_TRACE_POINTS 58 #include "gpu_scheduler_trace.h" 59 60 #define to_drm_sched_job(sched_job) \ 61 container_of((sched_job), struct drm_sched_job, queue_node) 62 63 static void drm_sched_process_job(struct dma_fence *f, struct dma_fence_cb *cb); 64 65 /** 66 * drm_sched_rq_init - initialize a given run queue struct 67 * 68 * @rq: scheduler run queue 69 * 70 * Initializes a scheduler runqueue. 71 */ 72 static void drm_sched_rq_init(struct drm_gpu_scheduler *sched, 73 struct drm_sched_rq *rq) 74 { 75 spin_lock_init(&rq->lock); 76 INIT_LIST_HEAD(&rq->entities); 77 rq->current_entity = NULL; 78 rq->sched = sched; 79 } 80 81 /** 82 * drm_sched_rq_add_entity - add an entity 83 * 84 * @rq: scheduler run queue 85 * @entity: scheduler entity 86 * 87 * Adds a scheduler entity to the run queue. 88 */ 89 void drm_sched_rq_add_entity(struct drm_sched_rq *rq, 90 struct drm_sched_entity *entity) 91 { 92 if (!list_empty(&entity->list)) 93 return; 94 spin_lock(&rq->lock); 95 list_add_tail(&entity->list, &rq->entities); 96 spin_unlock(&rq->lock); 97 } 98 99 /** 100 * drm_sched_rq_remove_entity - remove an entity 101 * 102 * @rq: scheduler run queue 103 * @entity: scheduler entity 104 * 105 * Removes a scheduler entity from the run queue. 106 */ 107 void drm_sched_rq_remove_entity(struct drm_sched_rq *rq, 108 struct drm_sched_entity *entity) 109 { 110 if (list_empty(&entity->list)) 111 return; 112 spin_lock(&rq->lock); 113 list_del_init(&entity->list); 114 if (rq->current_entity == entity) 115 rq->current_entity = NULL; 116 spin_unlock(&rq->lock); 117 } 118 119 /** 120 * drm_sched_rq_select_entity - Select an entity which could provide a job to run 121 * 122 * @rq: scheduler run queue to check. 123 * 124 * Try to find a ready entity, returns NULL if none found. 125 */ 126 static struct drm_sched_entity * 127 drm_sched_rq_select_entity(struct drm_sched_rq *rq) 128 { 129 struct drm_sched_entity *entity; 130 131 spin_lock(&rq->lock); 132 133 entity = rq->current_entity; 134 if (entity) { 135 list_for_each_entry_continue(entity, &rq->entities, list) { 136 if (drm_sched_entity_is_ready(entity)) { 137 rq->current_entity = entity; 138 reinit_completion(&entity->entity_idle); 139 spin_unlock(&rq->lock); 140 return entity; 141 } 142 } 143 } 144 145 list_for_each_entry(entity, &rq->entities, list) { 146 147 if (drm_sched_entity_is_ready(entity)) { 148 rq->current_entity = entity; 149 reinit_completion(&entity->entity_idle); 150 spin_unlock(&rq->lock); 151 return entity; 152 } 153 154 if (entity == rq->current_entity) 155 break; 156 } 157 158 spin_unlock(&rq->lock); 159 160 return NULL; 161 } 162 163 /** 164 * drm_sched_dependency_optimized 165 * 166 * @fence: the dependency fence 167 * @entity: the entity which depends on the above fence 168 * 169 * Returns true if the dependency can be optimized and false otherwise 170 */ 171 bool drm_sched_dependency_optimized(struct dma_fence* fence, 172 struct drm_sched_entity *entity) 173 { 174 struct drm_gpu_scheduler *sched = entity->rq->sched; 175 struct drm_sched_fence *s_fence; 176 177 if (!fence || dma_fence_is_signaled(fence)) 178 return false; 179 if (fence->context == entity->fence_context) 180 return true; 181 s_fence = to_drm_sched_fence(fence); 182 if (s_fence && s_fence->sched == sched) 183 return true; 184 185 return false; 186 } 187 EXPORT_SYMBOL(drm_sched_dependency_optimized); 188 189 /** 190 * drm_sched_start_timeout - start timeout for reset worker 191 * 192 * @sched: scheduler instance to start the worker for 193 * 194 * Start the timeout for the given scheduler. 195 */ 196 static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched) 197 { 198 if (sched->timeout != MAX_SCHEDULE_TIMEOUT && 199 !list_empty(&sched->ring_mirror_list)) 200 schedule_delayed_work(&sched->work_tdr, sched->timeout); 201 } 202 203 /** 204 * drm_sched_fault - immediately start timeout handler 205 * 206 * @sched: scheduler where the timeout handling should be started. 207 * 208 * Start timeout handling immediately when the driver detects a hardware fault. 209 */ 210 void drm_sched_fault(struct drm_gpu_scheduler *sched) 211 { 212 mod_delayed_work(system_wq, &sched->work_tdr, 0); 213 } 214 EXPORT_SYMBOL(drm_sched_fault); 215 216 /** 217 * drm_sched_suspend_timeout - Suspend scheduler job timeout 218 * 219 * @sched: scheduler instance for which to suspend the timeout 220 * 221 * Suspend the delayed work timeout for the scheduler. This is done by 222 * modifying the delayed work timeout to an arbitrary large value, 223 * MAX_SCHEDULE_TIMEOUT in this case. Note that this function can be 224 * called from an IRQ context. 225 * 226 * Returns the timeout remaining 227 * 228 */ 229 unsigned long drm_sched_suspend_timeout(struct drm_gpu_scheduler *sched) 230 { 231 unsigned long sched_timeout, now = jiffies; 232 233 sched_timeout = sched->work_tdr.timer.expires; 234 235 /* 236 * Modify the timeout to an arbitrarily large value. This also prevents 237 * the timeout to be restarted when new submissions arrive 238 */ 239 if (mod_delayed_work(system_wq, &sched->work_tdr, MAX_SCHEDULE_TIMEOUT) 240 && time_after(sched_timeout, now)) 241 return sched_timeout - now; 242 else 243 return sched->timeout; 244 } 245 EXPORT_SYMBOL(drm_sched_suspend_timeout); 246 247 /** 248 * drm_sched_resume_timeout - Resume scheduler job timeout 249 * 250 * @sched: scheduler instance for which to resume the timeout 251 * @remaining: remaining timeout 252 * 253 * Resume the delayed work timeout for the scheduler. Note that 254 * this function can be called from an IRQ context. 255 */ 256 void drm_sched_resume_timeout(struct drm_gpu_scheduler *sched, 257 unsigned long remaining) 258 { 259 unsigned long flags; 260 261 spin_lock_irqsave(&sched->job_list_lock, flags); 262 263 if (list_empty(&sched->ring_mirror_list)) 264 cancel_delayed_work(&sched->work_tdr); 265 else 266 mod_delayed_work(system_wq, &sched->work_tdr, remaining); 267 268 spin_unlock_irqrestore(&sched->job_list_lock, flags); 269 } 270 EXPORT_SYMBOL(drm_sched_resume_timeout); 271 272 static void drm_sched_job_begin(struct drm_sched_job *s_job) 273 { 274 struct drm_gpu_scheduler *sched = s_job->sched; 275 unsigned long flags; 276 277 spin_lock_irqsave(&sched->job_list_lock, flags); 278 list_add_tail(&s_job->node, &sched->ring_mirror_list); 279 drm_sched_start_timeout(sched); 280 spin_unlock_irqrestore(&sched->job_list_lock, flags); 281 } 282 283 static void drm_sched_job_timedout(struct work_struct *work) 284 { 285 struct drm_gpu_scheduler *sched; 286 struct drm_sched_job *job; 287 unsigned long flags; 288 289 sched = container_of(work, struct drm_gpu_scheduler, work_tdr.work); 290 job = list_first_entry_or_null(&sched->ring_mirror_list, 291 struct drm_sched_job, node); 292 293 if (job) { 294 job->sched->ops->timedout_job(job); 295 296 /* 297 * Guilty job did complete and hence needs to be manually removed 298 * See drm_sched_stop doc. 299 */ 300 if (sched->free_guilty) { 301 job->sched->ops->free_job(job); 302 sched->free_guilty = false; 303 } 304 } 305 306 spin_lock_irqsave(&sched->job_list_lock, flags); 307 drm_sched_start_timeout(sched); 308 spin_unlock_irqrestore(&sched->job_list_lock, flags); 309 } 310 311 /** 312 * drm_sched_increase_karma - Update sched_entity guilty flag 313 * 314 * @bad: The job guilty of time out 315 * 316 * Increment on every hang caused by the 'bad' job. If this exceeds the hang 317 * limit of the scheduler then the respective sched entity is marked guilty and 318 * jobs from it will not be scheduled further 319 */ 320 void drm_sched_increase_karma(struct drm_sched_job *bad) 321 { 322 int i; 323 struct drm_sched_entity *tmp; 324 struct drm_sched_entity *entity; 325 struct drm_gpu_scheduler *sched = bad->sched; 326 327 /* don't increase @bad's karma if it's from KERNEL RQ, 328 * because sometimes GPU hang would cause kernel jobs (like VM updating jobs) 329 * corrupt but keep in mind that kernel jobs always considered good. 330 */ 331 if (bad->s_priority != DRM_SCHED_PRIORITY_KERNEL) { 332 atomic_inc(&bad->karma); 333 for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_KERNEL; 334 i++) { 335 struct drm_sched_rq *rq = &sched->sched_rq[i]; 336 337 spin_lock(&rq->lock); 338 list_for_each_entry_safe(entity, tmp, &rq->entities, list) { 339 if (bad->s_fence->scheduled.context == 340 entity->fence_context) { 341 if (atomic_read(&bad->karma) > 342 bad->sched->hang_limit) 343 if (entity->guilty) 344 atomic_set(entity->guilty, 1); 345 break; 346 } 347 } 348 spin_unlock(&rq->lock); 349 if (&entity->list != &rq->entities) 350 break; 351 } 352 } 353 } 354 EXPORT_SYMBOL(drm_sched_increase_karma); 355 356 /** 357 * drm_sched_stop - stop the scheduler 358 * 359 * @sched: scheduler instance 360 * @bad: job which caused the time out 361 * 362 * Stop the scheduler and also removes and frees all completed jobs. 363 * Note: bad job will not be freed as it might be used later and so it's 364 * callers responsibility to release it manually if it's not part of the 365 * mirror list any more. 366 * 367 */ 368 void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad) 369 { 370 struct drm_sched_job *s_job, *tmp; 371 unsigned long flags; 372 373 kthread_park(sched->thread); 374 375 /* 376 * Iterate the job list from later to earlier one and either deactive 377 * their HW callbacks or remove them from mirror list if they already 378 * signaled. 379 * This iteration is thread safe as sched thread is stopped. 380 */ 381 list_for_each_entry_safe_reverse(s_job, tmp, &sched->ring_mirror_list, node) { 382 if (s_job->s_fence->parent && 383 dma_fence_remove_callback(s_job->s_fence->parent, 384 &s_job->cb)) { 385 atomic_dec(&sched->hw_rq_count); 386 } else { 387 /* 388 * remove job from ring_mirror_list. 389 * Locking here is for concurrent resume timeout 390 */ 391 spin_lock_irqsave(&sched->job_list_lock, flags); 392 list_del_init(&s_job->node); 393 spin_unlock_irqrestore(&sched->job_list_lock, flags); 394 395 /* 396 * Wait for job's HW fence callback to finish using s_job 397 * before releasing it. 398 * 399 * Job is still alive so fence refcount at least 1 400 */ 401 dma_fence_wait(&s_job->s_fence->finished, false); 402 403 /* 404 * We must keep bad job alive for later use during 405 * recovery by some of the drivers but leave a hint 406 * that the guilty job must be released. 407 */ 408 if (bad != s_job) 409 sched->ops->free_job(s_job); 410 else 411 sched->free_guilty = true; 412 } 413 } 414 415 /* 416 * Stop pending timer in flight as we rearm it in drm_sched_start. This 417 * avoids the pending timeout work in progress to fire right away after 418 * this TDR finished and before the newly restarted jobs had a 419 * chance to complete. 420 */ 421 cancel_delayed_work(&sched->work_tdr); 422 } 423 424 EXPORT_SYMBOL(drm_sched_stop); 425 426 /** 427 * drm_sched_job_recovery - recover jobs after a reset 428 * 429 * @sched: scheduler instance 430 * @full_recovery: proceed with complete sched restart 431 * 432 */ 433 void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery) 434 { 435 struct drm_sched_job *s_job, *tmp; 436 unsigned long flags; 437 int r; 438 439 /* 440 * Locking the list is not required here as the sched thread is parked 441 * so no new jobs are being inserted or removed. Also concurrent 442 * GPU recovers can't run in parallel. 443 */ 444 list_for_each_entry_safe(s_job, tmp, &sched->ring_mirror_list, node) { 445 struct dma_fence *fence = s_job->s_fence->parent; 446 447 atomic_inc(&sched->hw_rq_count); 448 449 if (!full_recovery) 450 continue; 451 452 if (fence) { 453 r = dma_fence_add_callback(fence, &s_job->cb, 454 drm_sched_process_job); 455 if (r == -ENOENT) 456 drm_sched_process_job(fence, &s_job->cb); 457 else if (r) 458 DRM_ERROR("fence add callback failed (%d)\n", 459 r); 460 } else 461 drm_sched_process_job(NULL, &s_job->cb); 462 } 463 464 if (full_recovery) { 465 spin_lock_irqsave(&sched->job_list_lock, flags); 466 drm_sched_start_timeout(sched); 467 spin_unlock_irqrestore(&sched->job_list_lock, flags); 468 } 469 470 kthread_unpark(sched->thread); 471 } 472 EXPORT_SYMBOL(drm_sched_start); 473 474 /** 475 * drm_sched_resubmit_jobs - helper to relunch job from mirror ring list 476 * 477 * @sched: scheduler instance 478 * 479 */ 480 void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched) 481 { 482 struct drm_sched_job *s_job, *tmp; 483 uint64_t guilty_context; 484 bool found_guilty = false; 485 struct dma_fence *fence; 486 487 list_for_each_entry_safe(s_job, tmp, &sched->ring_mirror_list, node) { 488 struct drm_sched_fence *s_fence = s_job->s_fence; 489 490 if (!found_guilty && atomic_read(&s_job->karma) > sched->hang_limit) { 491 found_guilty = true; 492 guilty_context = s_job->s_fence->scheduled.context; 493 } 494 495 if (found_guilty && s_job->s_fence->scheduled.context == guilty_context) 496 dma_fence_set_error(&s_fence->finished, -ECANCELED); 497 498 dma_fence_put(s_job->s_fence->parent); 499 fence = sched->ops->run_job(s_job); 500 501 if (IS_ERR_OR_NULL(fence)) { 502 if (IS_ERR(fence)) 503 dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); 504 505 s_job->s_fence->parent = NULL; 506 } else { 507 s_job->s_fence->parent = fence; 508 } 509 510 511 } 512 } 513 EXPORT_SYMBOL(drm_sched_resubmit_jobs); 514 515 /** 516 * drm_sched_job_init - init a scheduler job 517 * 518 * @job: scheduler job to init 519 * @entity: scheduler entity to use 520 * @owner: job owner for debugging 521 * 522 * Refer to drm_sched_entity_push_job() documentation 523 * for locking considerations. 524 * 525 * Returns 0 for success, negative error code otherwise. 526 */ 527 int drm_sched_job_init(struct drm_sched_job *job, 528 struct drm_sched_entity *entity, 529 void *owner) 530 { 531 struct drm_gpu_scheduler *sched; 532 533 drm_sched_entity_select_rq(entity); 534 if (!entity->rq) 535 return -ENOENT; 536 537 sched = entity->rq->sched; 538 539 job->sched = sched; 540 job->entity = entity; 541 job->s_priority = entity->rq - sched->sched_rq; 542 job->s_fence = drm_sched_fence_create(entity, owner); 543 if (!job->s_fence) 544 return -ENOMEM; 545 job->id = atomic64_inc_return(&sched->job_id_count); 546 547 INIT_LIST_HEAD(&job->node); 548 549 return 0; 550 } 551 EXPORT_SYMBOL(drm_sched_job_init); 552 553 /** 554 * drm_sched_job_cleanup - clean up scheduler job resources 555 * 556 * @job: scheduler job to clean up 557 */ 558 void drm_sched_job_cleanup(struct drm_sched_job *job) 559 { 560 dma_fence_put(&job->s_fence->finished); 561 job->s_fence = NULL; 562 } 563 EXPORT_SYMBOL(drm_sched_job_cleanup); 564 565 /** 566 * drm_sched_ready - is the scheduler ready 567 * 568 * @sched: scheduler instance 569 * 570 * Return true if we can push more jobs to the hw, otherwise false. 571 */ 572 static bool drm_sched_ready(struct drm_gpu_scheduler *sched) 573 { 574 return atomic_read(&sched->hw_rq_count) < 575 sched->hw_submission_limit; 576 } 577 578 /** 579 * drm_sched_wakeup - Wake up the scheduler when it is ready 580 * 581 * @sched: scheduler instance 582 * 583 */ 584 void drm_sched_wakeup(struct drm_gpu_scheduler *sched) 585 { 586 if (drm_sched_ready(sched)) 587 wake_up_interruptible(&sched->wake_up_worker); 588 } 589 590 /** 591 * drm_sched_select_entity - Select next entity to process 592 * 593 * @sched: scheduler instance 594 * 595 * Returns the entity to process or NULL if none are found. 596 */ 597 static struct drm_sched_entity * 598 drm_sched_select_entity(struct drm_gpu_scheduler *sched) 599 { 600 struct drm_sched_entity *entity; 601 int i; 602 603 if (!drm_sched_ready(sched)) 604 return NULL; 605 606 /* Kernel run queue has higher priority than normal run queue*/ 607 for (i = DRM_SCHED_PRIORITY_MAX - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) { 608 entity = drm_sched_rq_select_entity(&sched->sched_rq[i]); 609 if (entity) 610 break; 611 } 612 613 return entity; 614 } 615 616 /** 617 * drm_sched_process_job - process a job 618 * 619 * @f: fence 620 * @cb: fence callbacks 621 * 622 * Called after job has finished execution. 623 */ 624 static void drm_sched_process_job(struct dma_fence *f, struct dma_fence_cb *cb) 625 { 626 struct drm_sched_job *s_job = container_of(cb, struct drm_sched_job, cb); 627 struct drm_sched_fence *s_fence = s_job->s_fence; 628 struct drm_gpu_scheduler *sched = s_fence->sched; 629 630 atomic_dec(&sched->hw_rq_count); 631 atomic_dec(&sched->num_jobs); 632 633 trace_drm_sched_process_job(s_fence); 634 635 drm_sched_fence_finished(s_fence); 636 wake_up_interruptible(&sched->wake_up_worker); 637 } 638 639 /** 640 * drm_sched_get_cleanup_job - fetch the next finished job to be destroyed 641 * 642 * @sched: scheduler instance 643 * 644 * Returns the next finished job from the mirror list (if there is one) 645 * ready for it to be destroyed. 646 */ 647 static struct drm_sched_job * 648 drm_sched_get_cleanup_job(struct drm_gpu_scheduler *sched) 649 { 650 struct drm_sched_job *job; 651 unsigned long flags; 652 653 /* 654 * Don't destroy jobs while the timeout worker is running OR thread 655 * is being parked and hence assumed to not touch ring_mirror_list 656 */ 657 if ((sched->timeout != MAX_SCHEDULE_TIMEOUT && 658 !cancel_delayed_work(&sched->work_tdr)) || 659 __kthread_should_park(sched->thread)) 660 return NULL; 661 662 spin_lock_irqsave(&sched->job_list_lock, flags); 663 664 job = list_first_entry_or_null(&sched->ring_mirror_list, 665 struct drm_sched_job, node); 666 667 if (job && dma_fence_is_signaled(&job->s_fence->finished)) { 668 /* remove job from ring_mirror_list */ 669 list_del_init(&job->node); 670 } else { 671 job = NULL; 672 /* queue timeout for next job */ 673 drm_sched_start_timeout(sched); 674 } 675 676 spin_unlock_irqrestore(&sched->job_list_lock, flags); 677 678 return job; 679 } 680 681 /** 682 * drm_sched_blocked - check if the scheduler is blocked 683 * 684 * @sched: scheduler instance 685 * 686 * Returns true if blocked, otherwise false. 687 */ 688 static bool drm_sched_blocked(struct drm_gpu_scheduler *sched) 689 { 690 if (kthread_should_park()) { 691 kthread_parkme(); 692 return true; 693 } 694 695 return false; 696 } 697 698 /** 699 * drm_sched_main - main scheduler thread 700 * 701 * @param: scheduler instance 702 * 703 * Returns 0. 704 */ 705 static int drm_sched_main(void *param) 706 { 707 struct sched_param sparam = {.sched_priority = 1}; 708 struct drm_gpu_scheduler *sched = (struct drm_gpu_scheduler *)param; 709 int r; 710 711 sched_setscheduler(current, SCHED_FIFO, &sparam); 712 713 while (!kthread_should_stop()) { 714 struct drm_sched_entity *entity = NULL; 715 struct drm_sched_fence *s_fence; 716 struct drm_sched_job *sched_job; 717 struct dma_fence *fence; 718 struct drm_sched_job *cleanup_job = NULL; 719 720 wait_event_interruptible(sched->wake_up_worker, 721 (cleanup_job = drm_sched_get_cleanup_job(sched)) || 722 (!drm_sched_blocked(sched) && 723 (entity = drm_sched_select_entity(sched))) || 724 kthread_should_stop()); 725 726 if (cleanup_job) { 727 sched->ops->free_job(cleanup_job); 728 /* queue timeout for next job */ 729 drm_sched_start_timeout(sched); 730 } 731 732 if (!entity) 733 continue; 734 735 sched_job = drm_sched_entity_pop_job(entity); 736 737 complete(&entity->entity_idle); 738 739 if (!sched_job) 740 continue; 741 742 s_fence = sched_job->s_fence; 743 744 atomic_inc(&sched->hw_rq_count); 745 drm_sched_job_begin(sched_job); 746 747 fence = sched->ops->run_job(sched_job); 748 drm_sched_fence_scheduled(s_fence); 749 750 if (!IS_ERR_OR_NULL(fence)) { 751 s_fence->parent = dma_fence_get(fence); 752 r = dma_fence_add_callback(fence, &sched_job->cb, 753 drm_sched_process_job); 754 if (r == -ENOENT) 755 drm_sched_process_job(fence, &sched_job->cb); 756 else if (r) 757 DRM_ERROR("fence add callback failed (%d)\n", 758 r); 759 dma_fence_put(fence); 760 } else { 761 if (IS_ERR(fence)) 762 dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); 763 764 drm_sched_process_job(NULL, &sched_job->cb); 765 } 766 767 wake_up(&sched->job_scheduled); 768 } 769 return 0; 770 } 771 772 /** 773 * drm_sched_init - Init a gpu scheduler instance 774 * 775 * @sched: scheduler instance 776 * @ops: backend operations for this scheduler 777 * @hw_submission: number of hw submissions that can be in flight 778 * @hang_limit: number of times to allow a job to hang before dropping it 779 * @timeout: timeout value in jiffies for the scheduler 780 * @name: name used for debugging 781 * 782 * Return 0 on success, otherwise error code. 783 */ 784 int drm_sched_init(struct drm_gpu_scheduler *sched, 785 const struct drm_sched_backend_ops *ops, 786 unsigned hw_submission, 787 unsigned hang_limit, 788 long timeout, 789 const char *name) 790 { 791 int i, ret; 792 sched->ops = ops; 793 sched->hw_submission_limit = hw_submission; 794 sched->name = name; 795 sched->timeout = timeout; 796 sched->hang_limit = hang_limit; 797 for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_MAX; i++) 798 drm_sched_rq_init(sched, &sched->sched_rq[i]); 799 800 init_waitqueue_head(&sched->wake_up_worker); 801 init_waitqueue_head(&sched->job_scheduled); 802 INIT_LIST_HEAD(&sched->ring_mirror_list); 803 spin_lock_init(&sched->job_list_lock); 804 atomic_set(&sched->hw_rq_count, 0); 805 INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout); 806 atomic_set(&sched->num_jobs, 0); 807 atomic64_set(&sched->job_id_count, 0); 808 809 /* Each scheduler will run on a seperate kernel thread */ 810 sched->thread = kthread_run(drm_sched_main, sched, sched->name); 811 if (IS_ERR(sched->thread)) { 812 ret = PTR_ERR(sched->thread); 813 sched->thread = NULL; 814 DRM_ERROR("Failed to create scheduler for %s.\n", name); 815 return ret; 816 } 817 818 sched->ready = true; 819 return 0; 820 } 821 EXPORT_SYMBOL(drm_sched_init); 822 823 /** 824 * drm_sched_fini - Destroy a gpu scheduler 825 * 826 * @sched: scheduler instance 827 * 828 * Tears down and cleans up the scheduler. 829 */ 830 void drm_sched_fini(struct drm_gpu_scheduler *sched) 831 { 832 if (sched->thread) 833 kthread_stop(sched->thread); 834 835 sched->ready = false; 836 } 837 EXPORT_SYMBOL(drm_sched_fini); 838