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 * Note that once a job was taken from the entities queue and pushed to the 47 * hardware, i.e. the pending queue, the entity must not be referenced anymore 48 * through the jobs entity pointer. 49 */ 50 51 /** 52 * DOC: Flow Control 53 * 54 * The DRM GPU scheduler provides a flow control mechanism to regulate the rate 55 * in which the jobs fetched from scheduler entities are executed. 56 * 57 * In this context the &drm_gpu_scheduler keeps track of a driver specified 58 * credit limit representing the capacity of this scheduler and a credit count; 59 * every &drm_sched_job carries a driver specified number of credits. 60 * 61 * Once a job is executed (but not yet finished), the job's credits contribute 62 * to the scheduler's credit count until the job is finished. If by executing 63 * one more job the scheduler's credit count would exceed the scheduler's 64 * credit limit, the job won't be executed. Instead, the scheduler will wait 65 * until the credit count has decreased enough to not overflow its credit limit. 66 * This implies waiting for previously executed jobs. 67 * 68 * Optionally, drivers may register a callback (update_job_credits) provided by 69 * struct drm_sched_backend_ops to update the job's credits dynamically. The 70 * scheduler executes this callback every time the scheduler considers a job for 71 * execution and subsequently checks whether the job fits the scheduler's credit 72 * limit. 73 */ 74 75 #include <linux/wait.h> 76 #include <linux/sched.h> 77 #include <linux/completion.h> 78 #include <linux/dma-resv.h> 79 #include <uapi/linux/sched/types.h> 80 81 #include <drm/drm_print.h> 82 #include <drm/drm_gem.h> 83 #include <drm/drm_syncobj.h> 84 #include <drm/gpu_scheduler.h> 85 #include <drm/spsc_queue.h> 86 87 #define CREATE_TRACE_POINTS 88 #include "gpu_scheduler_trace.h" 89 90 #define to_drm_sched_job(sched_job) \ 91 container_of((sched_job), struct drm_sched_job, queue_node) 92 93 int drm_sched_policy = DRM_SCHED_POLICY_FIFO; 94 95 /** 96 * DOC: sched_policy (int) 97 * Used to override default entities scheduling policy in a run queue. 98 */ 99 MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default)."); 100 module_param_named(sched_policy, drm_sched_policy, int, 0444); 101 102 static u32 drm_sched_available_credits(struct drm_gpu_scheduler *sched) 103 { 104 u32 credits; 105 106 drm_WARN_ON(sched, check_sub_overflow(sched->credit_limit, 107 atomic_read(&sched->credit_count), 108 &credits)); 109 110 return credits; 111 } 112 113 /** 114 * drm_sched_can_queue -- Can we queue more to the hardware? 115 * @sched: scheduler instance 116 * @entity: the scheduler entity 117 * 118 * Return true if we can push at least one more job from @entity, false 119 * otherwise. 120 */ 121 static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched, 122 struct drm_sched_entity *entity) 123 { 124 struct drm_sched_job *s_job; 125 126 s_job = to_drm_sched_job(spsc_queue_peek(&entity->job_queue)); 127 if (!s_job) 128 return false; 129 130 if (sched->ops->update_job_credits) { 131 s_job->credits = sched->ops->update_job_credits(s_job); 132 133 drm_WARN(sched, !s_job->credits, 134 "Jobs with zero credits bypass job-flow control.\n"); 135 } 136 137 /* If a job exceeds the credit limit, truncate it to the credit limit 138 * itself to guarantee forward progress. 139 */ 140 if (drm_WARN(sched, s_job->credits > sched->credit_limit, 141 "Jobs may not exceed the credit limit, truncate.\n")) 142 s_job->credits = sched->credit_limit; 143 144 return drm_sched_available_credits(sched) >= s_job->credits; 145 } 146 147 static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a, 148 const struct rb_node *b) 149 { 150 struct drm_sched_entity *ent_a = rb_entry((a), struct drm_sched_entity, rb_tree_node); 151 struct drm_sched_entity *ent_b = rb_entry((b), struct drm_sched_entity, rb_tree_node); 152 153 return ktime_before(ent_a->oldest_job_waiting, ent_b->oldest_job_waiting); 154 } 155 156 static inline void drm_sched_rq_remove_fifo_locked(struct drm_sched_entity *entity) 157 { 158 struct drm_sched_rq *rq = entity->rq; 159 160 if (!RB_EMPTY_NODE(&entity->rb_tree_node)) { 161 rb_erase_cached(&entity->rb_tree_node, &rq->rb_tree_root); 162 RB_CLEAR_NODE(&entity->rb_tree_node); 163 } 164 } 165 166 void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts) 167 { 168 /* 169 * Both locks need to be grabbed, one to protect from entity->rq change 170 * for entity from within concurrent drm_sched_entity_select_rq and the 171 * other to update the rb tree structure. 172 */ 173 spin_lock(&entity->rq_lock); 174 spin_lock(&entity->rq->lock); 175 176 drm_sched_rq_remove_fifo_locked(entity); 177 178 entity->oldest_job_waiting = ts; 179 180 rb_add_cached(&entity->rb_tree_node, &entity->rq->rb_tree_root, 181 drm_sched_entity_compare_before); 182 183 spin_unlock(&entity->rq->lock); 184 spin_unlock(&entity->rq_lock); 185 } 186 187 /** 188 * drm_sched_rq_init - initialize a given run queue struct 189 * 190 * @sched: scheduler instance to associate with this run queue 191 * @rq: scheduler run queue 192 * 193 * Initializes a scheduler runqueue. 194 */ 195 static void drm_sched_rq_init(struct drm_gpu_scheduler *sched, 196 struct drm_sched_rq *rq) 197 { 198 spin_lock_init(&rq->lock); 199 INIT_LIST_HEAD(&rq->entities); 200 rq->rb_tree_root = RB_ROOT_CACHED; 201 rq->current_entity = NULL; 202 rq->sched = sched; 203 } 204 205 /** 206 * drm_sched_rq_add_entity - add an entity 207 * 208 * @rq: scheduler run queue 209 * @entity: scheduler entity 210 * 211 * Adds a scheduler entity to the run queue. 212 */ 213 void drm_sched_rq_add_entity(struct drm_sched_rq *rq, 214 struct drm_sched_entity *entity) 215 { 216 if (!list_empty(&entity->list)) 217 return; 218 219 spin_lock(&rq->lock); 220 221 atomic_inc(rq->sched->score); 222 list_add_tail(&entity->list, &rq->entities); 223 224 spin_unlock(&rq->lock); 225 } 226 227 /** 228 * drm_sched_rq_remove_entity - remove an entity 229 * 230 * @rq: scheduler run queue 231 * @entity: scheduler entity 232 * 233 * Removes a scheduler entity from the run queue. 234 */ 235 void drm_sched_rq_remove_entity(struct drm_sched_rq *rq, 236 struct drm_sched_entity *entity) 237 { 238 if (list_empty(&entity->list)) 239 return; 240 241 spin_lock(&rq->lock); 242 243 atomic_dec(rq->sched->score); 244 list_del_init(&entity->list); 245 246 if (rq->current_entity == entity) 247 rq->current_entity = NULL; 248 249 if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) 250 drm_sched_rq_remove_fifo_locked(entity); 251 252 spin_unlock(&rq->lock); 253 } 254 255 /** 256 * drm_sched_rq_select_entity_rr - Select an entity which could provide a job to run 257 * 258 * @sched: the gpu scheduler 259 * @rq: scheduler run queue to check. 260 * 261 * Try to find the next ready entity. 262 * 263 * Return an entity if one is found; return an error-pointer (!NULL) if an 264 * entity was ready, but the scheduler had insufficient credits to accommodate 265 * its job; return NULL, if no ready entity was found. 266 */ 267 static struct drm_sched_entity * 268 drm_sched_rq_select_entity_rr(struct drm_gpu_scheduler *sched, 269 struct drm_sched_rq *rq) 270 { 271 struct drm_sched_entity *entity; 272 273 spin_lock(&rq->lock); 274 275 entity = rq->current_entity; 276 if (entity) { 277 list_for_each_entry_continue(entity, &rq->entities, list) { 278 if (drm_sched_entity_is_ready(entity)) { 279 /* If we can't queue yet, preserve the current 280 * entity in terms of fairness. 281 */ 282 if (!drm_sched_can_queue(sched, entity)) { 283 spin_unlock(&rq->lock); 284 return ERR_PTR(-ENOSPC); 285 } 286 287 rq->current_entity = entity; 288 reinit_completion(&entity->entity_idle); 289 spin_unlock(&rq->lock); 290 return entity; 291 } 292 } 293 } 294 295 list_for_each_entry(entity, &rq->entities, list) { 296 if (drm_sched_entity_is_ready(entity)) { 297 /* If we can't queue yet, preserve the current entity in 298 * terms of fairness. 299 */ 300 if (!drm_sched_can_queue(sched, entity)) { 301 spin_unlock(&rq->lock); 302 return ERR_PTR(-ENOSPC); 303 } 304 305 rq->current_entity = entity; 306 reinit_completion(&entity->entity_idle); 307 spin_unlock(&rq->lock); 308 return entity; 309 } 310 311 if (entity == rq->current_entity) 312 break; 313 } 314 315 spin_unlock(&rq->lock); 316 317 return NULL; 318 } 319 320 /** 321 * drm_sched_rq_select_entity_fifo - Select an entity which provides a job to run 322 * 323 * @sched: the gpu scheduler 324 * @rq: scheduler run queue to check. 325 * 326 * Find oldest waiting ready entity. 327 * 328 * Return an entity if one is found; return an error-pointer (!NULL) if an 329 * entity was ready, but the scheduler had insufficient credits to accommodate 330 * its job; return NULL, if no ready entity was found. 331 */ 332 static struct drm_sched_entity * 333 drm_sched_rq_select_entity_fifo(struct drm_gpu_scheduler *sched, 334 struct drm_sched_rq *rq) 335 { 336 struct rb_node *rb; 337 338 spin_lock(&rq->lock); 339 for (rb = rb_first_cached(&rq->rb_tree_root); rb; rb = rb_next(rb)) { 340 struct drm_sched_entity *entity; 341 342 entity = rb_entry(rb, struct drm_sched_entity, rb_tree_node); 343 if (drm_sched_entity_is_ready(entity)) { 344 /* If we can't queue yet, preserve the current entity in 345 * terms of fairness. 346 */ 347 if (!drm_sched_can_queue(sched, entity)) { 348 spin_unlock(&rq->lock); 349 return ERR_PTR(-ENOSPC); 350 } 351 352 rq->current_entity = entity; 353 reinit_completion(&entity->entity_idle); 354 break; 355 } 356 } 357 spin_unlock(&rq->lock); 358 359 return rb ? rb_entry(rb, struct drm_sched_entity, rb_tree_node) : NULL; 360 } 361 362 /** 363 * drm_sched_run_job_queue - enqueue run-job work 364 * @sched: scheduler instance 365 */ 366 static void drm_sched_run_job_queue(struct drm_gpu_scheduler *sched) 367 { 368 if (!READ_ONCE(sched->pause_submit)) 369 queue_work(sched->submit_wq, &sched->work_run_job); 370 } 371 372 /** 373 * __drm_sched_run_free_queue - enqueue free-job work 374 * @sched: scheduler instance 375 */ 376 static void __drm_sched_run_free_queue(struct drm_gpu_scheduler *sched) 377 { 378 if (!READ_ONCE(sched->pause_submit)) 379 queue_work(sched->submit_wq, &sched->work_free_job); 380 } 381 382 /** 383 * drm_sched_run_free_queue - enqueue free-job work if ready 384 * @sched: scheduler instance 385 */ 386 static void drm_sched_run_free_queue(struct drm_gpu_scheduler *sched) 387 { 388 struct drm_sched_job *job; 389 390 spin_lock(&sched->job_list_lock); 391 job = list_first_entry_or_null(&sched->pending_list, 392 struct drm_sched_job, list); 393 if (job && dma_fence_is_signaled(&job->s_fence->finished)) 394 __drm_sched_run_free_queue(sched); 395 spin_unlock(&sched->job_list_lock); 396 } 397 398 /** 399 * drm_sched_job_done - complete a job 400 * @s_job: pointer to the job which is done 401 * 402 * Finish the job's fence and wake up the worker thread. 403 */ 404 static void drm_sched_job_done(struct drm_sched_job *s_job, int result) 405 { 406 struct drm_sched_fence *s_fence = s_job->s_fence; 407 struct drm_gpu_scheduler *sched = s_fence->sched; 408 409 atomic_sub(s_job->credits, &sched->credit_count); 410 atomic_dec(sched->score); 411 412 trace_drm_sched_process_job(s_fence); 413 414 dma_fence_get(&s_fence->finished); 415 drm_sched_fence_finished(s_fence, result); 416 dma_fence_put(&s_fence->finished); 417 __drm_sched_run_free_queue(sched); 418 } 419 420 /** 421 * drm_sched_job_done_cb - the callback for a done job 422 * @f: fence 423 * @cb: fence callbacks 424 */ 425 static void drm_sched_job_done_cb(struct dma_fence *f, struct dma_fence_cb *cb) 426 { 427 struct drm_sched_job *s_job = container_of(cb, struct drm_sched_job, cb); 428 429 drm_sched_job_done(s_job, f->error); 430 } 431 432 /** 433 * drm_sched_start_timeout - start timeout for reset worker 434 * 435 * @sched: scheduler instance to start the worker for 436 * 437 * Start the timeout for the given scheduler. 438 */ 439 static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched) 440 { 441 lockdep_assert_held(&sched->job_list_lock); 442 443 if (sched->timeout != MAX_SCHEDULE_TIMEOUT && 444 !list_empty(&sched->pending_list)) 445 mod_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout); 446 } 447 448 static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched) 449 { 450 spin_lock(&sched->job_list_lock); 451 drm_sched_start_timeout(sched); 452 spin_unlock(&sched->job_list_lock); 453 } 454 455 /** 456 * drm_sched_tdr_queue_imm: - immediately start job timeout handler 457 * 458 * @sched: scheduler for which the timeout handling should be started. 459 * 460 * Start timeout handling immediately for the named scheduler. 461 */ 462 void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched) 463 { 464 spin_lock(&sched->job_list_lock); 465 sched->timeout = 0; 466 drm_sched_start_timeout(sched); 467 spin_unlock(&sched->job_list_lock); 468 } 469 EXPORT_SYMBOL(drm_sched_tdr_queue_imm); 470 471 /** 472 * drm_sched_fault - immediately start timeout handler 473 * 474 * @sched: scheduler where the timeout handling should be started. 475 * 476 * Start timeout handling immediately when the driver detects a hardware fault. 477 */ 478 void drm_sched_fault(struct drm_gpu_scheduler *sched) 479 { 480 if (sched->timeout_wq) 481 mod_delayed_work(sched->timeout_wq, &sched->work_tdr, 0); 482 } 483 EXPORT_SYMBOL(drm_sched_fault); 484 485 /** 486 * drm_sched_suspend_timeout - Suspend scheduler job timeout 487 * 488 * @sched: scheduler instance for which to suspend the timeout 489 * 490 * Suspend the delayed work timeout for the scheduler. This is done by 491 * modifying the delayed work timeout to an arbitrary large value, 492 * MAX_SCHEDULE_TIMEOUT in this case. 493 * 494 * Returns the timeout remaining 495 * 496 */ 497 unsigned long drm_sched_suspend_timeout(struct drm_gpu_scheduler *sched) 498 { 499 unsigned long sched_timeout, now = jiffies; 500 501 sched_timeout = sched->work_tdr.timer.expires; 502 503 /* 504 * Modify the timeout to an arbitrarily large value. This also prevents 505 * the timeout to be restarted when new submissions arrive 506 */ 507 if (mod_delayed_work(sched->timeout_wq, &sched->work_tdr, MAX_SCHEDULE_TIMEOUT) 508 && time_after(sched_timeout, now)) 509 return sched_timeout - now; 510 else 511 return sched->timeout; 512 } 513 EXPORT_SYMBOL(drm_sched_suspend_timeout); 514 515 /** 516 * drm_sched_resume_timeout - Resume scheduler job timeout 517 * 518 * @sched: scheduler instance for which to resume the timeout 519 * @remaining: remaining timeout 520 * 521 * Resume the delayed work timeout for the scheduler. 522 */ 523 void drm_sched_resume_timeout(struct drm_gpu_scheduler *sched, 524 unsigned long remaining) 525 { 526 spin_lock(&sched->job_list_lock); 527 528 if (list_empty(&sched->pending_list)) 529 cancel_delayed_work(&sched->work_tdr); 530 else 531 mod_delayed_work(sched->timeout_wq, &sched->work_tdr, remaining); 532 533 spin_unlock(&sched->job_list_lock); 534 } 535 EXPORT_SYMBOL(drm_sched_resume_timeout); 536 537 static void drm_sched_job_begin(struct drm_sched_job *s_job) 538 { 539 struct drm_gpu_scheduler *sched = s_job->sched; 540 541 spin_lock(&sched->job_list_lock); 542 list_add_tail(&s_job->list, &sched->pending_list); 543 drm_sched_start_timeout(sched); 544 spin_unlock(&sched->job_list_lock); 545 } 546 547 static void drm_sched_job_timedout(struct work_struct *work) 548 { 549 struct drm_gpu_scheduler *sched; 550 struct drm_sched_job *job; 551 enum drm_gpu_sched_stat status = DRM_GPU_SCHED_STAT_NOMINAL; 552 553 sched = container_of(work, struct drm_gpu_scheduler, work_tdr.work); 554 555 /* Protects against concurrent deletion in drm_sched_get_finished_job */ 556 spin_lock(&sched->job_list_lock); 557 job = list_first_entry_or_null(&sched->pending_list, 558 struct drm_sched_job, list); 559 560 if (job) { 561 /* 562 * Remove the bad job so it cannot be freed by concurrent 563 * drm_sched_cleanup_jobs. It will be reinserted back after sched->thread 564 * is parked at which point it's safe. 565 */ 566 list_del_init(&job->list); 567 spin_unlock(&sched->job_list_lock); 568 569 status = job->sched->ops->timedout_job(job); 570 571 /* 572 * Guilty job did complete and hence needs to be manually removed 573 * See drm_sched_stop doc. 574 */ 575 if (sched->free_guilty) { 576 job->sched->ops->free_job(job); 577 sched->free_guilty = false; 578 } 579 } else { 580 spin_unlock(&sched->job_list_lock); 581 } 582 583 if (status != DRM_GPU_SCHED_STAT_ENODEV) 584 drm_sched_start_timeout_unlocked(sched); 585 } 586 587 /** 588 * drm_sched_stop - stop the scheduler 589 * 590 * @sched: scheduler instance 591 * @bad: job which caused the time out 592 * 593 * Stop the scheduler and also removes and frees all completed jobs. 594 * Note: bad job will not be freed as it might be used later and so it's 595 * callers responsibility to release it manually if it's not part of the 596 * pending list any more. 597 * 598 */ 599 void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad) 600 { 601 struct drm_sched_job *s_job, *tmp; 602 603 drm_sched_wqueue_stop(sched); 604 605 /* 606 * Reinsert back the bad job here - now it's safe as 607 * drm_sched_get_finished_job cannot race against us and release the 608 * bad job at this point - we parked (waited for) any in progress 609 * (earlier) cleanups and drm_sched_get_finished_job will not be called 610 * now until the scheduler thread is unparked. 611 */ 612 if (bad && bad->sched == sched) 613 /* 614 * Add at the head of the queue to reflect it was the earliest 615 * job extracted. 616 */ 617 list_add(&bad->list, &sched->pending_list); 618 619 /* 620 * Iterate the job list from later to earlier one and either deactive 621 * their HW callbacks or remove them from pending list if they already 622 * signaled. 623 * This iteration is thread safe as sched thread is stopped. 624 */ 625 list_for_each_entry_safe_reverse(s_job, tmp, &sched->pending_list, 626 list) { 627 if (s_job->s_fence->parent && 628 dma_fence_remove_callback(s_job->s_fence->parent, 629 &s_job->cb)) { 630 dma_fence_put(s_job->s_fence->parent); 631 s_job->s_fence->parent = NULL; 632 atomic_sub(s_job->credits, &sched->credit_count); 633 } else { 634 /* 635 * remove job from pending_list. 636 * Locking here is for concurrent resume timeout 637 */ 638 spin_lock(&sched->job_list_lock); 639 list_del_init(&s_job->list); 640 spin_unlock(&sched->job_list_lock); 641 642 /* 643 * Wait for job's HW fence callback to finish using s_job 644 * before releasing it. 645 * 646 * Job is still alive so fence refcount at least 1 647 */ 648 dma_fence_wait(&s_job->s_fence->finished, false); 649 650 /* 651 * We must keep bad job alive for later use during 652 * recovery by some of the drivers but leave a hint 653 * that the guilty job must be released. 654 */ 655 if (bad != s_job) 656 sched->ops->free_job(s_job); 657 else 658 sched->free_guilty = true; 659 } 660 } 661 662 /* 663 * Stop pending timer in flight as we rearm it in drm_sched_start. This 664 * avoids the pending timeout work in progress to fire right away after 665 * this TDR finished and before the newly restarted jobs had a 666 * chance to complete. 667 */ 668 cancel_delayed_work(&sched->work_tdr); 669 } 670 671 EXPORT_SYMBOL(drm_sched_stop); 672 673 /** 674 * drm_sched_start - recover jobs after a reset 675 * 676 * @sched: scheduler instance 677 * 678 */ 679 void drm_sched_start(struct drm_gpu_scheduler *sched) 680 { 681 struct drm_sched_job *s_job, *tmp; 682 683 /* 684 * Locking the list is not required here as the sched thread is parked 685 * so no new jobs are being inserted or removed. Also concurrent 686 * GPU recovers can't run in parallel. 687 */ 688 list_for_each_entry_safe(s_job, tmp, &sched->pending_list, list) { 689 struct dma_fence *fence = s_job->s_fence->parent; 690 691 atomic_add(s_job->credits, &sched->credit_count); 692 693 if (!fence) { 694 drm_sched_job_done(s_job, -ECANCELED); 695 continue; 696 } 697 698 if (dma_fence_add_callback(fence, &s_job->cb, 699 drm_sched_job_done_cb)) 700 drm_sched_job_done(s_job, fence->error); 701 } 702 703 drm_sched_start_timeout_unlocked(sched); 704 drm_sched_wqueue_start(sched); 705 } 706 EXPORT_SYMBOL(drm_sched_start); 707 708 /** 709 * drm_sched_resubmit_jobs - Deprecated, don't use in new code! 710 * 711 * @sched: scheduler instance 712 * 713 * Re-submitting jobs was a concept AMD came up as cheap way to implement 714 * recovery after a job timeout. 715 * 716 * This turned out to be not working very well. First of all there are many 717 * problem with the dma_fence implementation and requirements. Either the 718 * implementation is risking deadlocks with core memory management or violating 719 * documented implementation details of the dma_fence object. 720 * 721 * Drivers can still save and restore their state for recovery operations, but 722 * we shouldn't make this a general scheduler feature around the dma_fence 723 * interface. 724 */ 725 void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched) 726 { 727 struct drm_sched_job *s_job, *tmp; 728 uint64_t guilty_context; 729 bool found_guilty = false; 730 struct dma_fence *fence; 731 732 list_for_each_entry_safe(s_job, tmp, &sched->pending_list, list) { 733 struct drm_sched_fence *s_fence = s_job->s_fence; 734 735 if (!found_guilty && atomic_read(&s_job->karma) > sched->hang_limit) { 736 found_guilty = true; 737 guilty_context = s_job->s_fence->scheduled.context; 738 } 739 740 if (found_guilty && s_job->s_fence->scheduled.context == guilty_context) 741 dma_fence_set_error(&s_fence->finished, -ECANCELED); 742 743 fence = sched->ops->run_job(s_job); 744 745 if (IS_ERR_OR_NULL(fence)) { 746 if (IS_ERR(fence)) 747 dma_fence_set_error(&s_fence->finished, PTR_ERR(fence)); 748 749 s_job->s_fence->parent = NULL; 750 } else { 751 752 s_job->s_fence->parent = dma_fence_get(fence); 753 754 /* Drop for orignal kref_init */ 755 dma_fence_put(fence); 756 } 757 } 758 } 759 EXPORT_SYMBOL(drm_sched_resubmit_jobs); 760 761 /** 762 * drm_sched_job_init - init a scheduler job 763 * @job: scheduler job to init 764 * @entity: scheduler entity to use 765 * @credits: the number of credits this job contributes to the schedulers 766 * credit limit 767 * @owner: job owner for debugging 768 * 769 * Refer to drm_sched_entity_push_job() documentation 770 * for locking considerations. 771 * 772 * Drivers must make sure drm_sched_job_cleanup() if this function returns 773 * successfully, even when @job is aborted before drm_sched_job_arm() is called. 774 * 775 * WARNING: amdgpu abuses &drm_sched.ready to signal when the hardware 776 * has died, which can mean that there's no valid runqueue for a @entity. 777 * This function returns -ENOENT in this case (which probably should be -EIO as 778 * a more meanigful return value). 779 * 780 * Returns 0 for success, negative error code otherwise. 781 */ 782 int drm_sched_job_init(struct drm_sched_job *job, 783 struct drm_sched_entity *entity, 784 u32 credits, void *owner) 785 { 786 if (!entity->rq) { 787 /* This will most likely be followed by missing frames 788 * or worse--a blank screen--leave a trail in the 789 * logs, so this can be debugged easier. 790 */ 791 drm_err(job->sched, "%s: entity has no rq!\n", __func__); 792 return -ENOENT; 793 } 794 795 if (unlikely(!credits)) { 796 pr_err("*ERROR* %s: credits cannot be 0!\n", __func__); 797 return -EINVAL; 798 } 799 800 job->entity = entity; 801 job->credits = credits; 802 job->s_fence = drm_sched_fence_alloc(entity, owner); 803 if (!job->s_fence) 804 return -ENOMEM; 805 806 INIT_LIST_HEAD(&job->list); 807 808 xa_init_flags(&job->dependencies, XA_FLAGS_ALLOC); 809 810 return 0; 811 } 812 EXPORT_SYMBOL(drm_sched_job_init); 813 814 /** 815 * drm_sched_job_arm - arm a scheduler job for execution 816 * @job: scheduler job to arm 817 * 818 * This arms a scheduler job for execution. Specifically it initializes the 819 * &drm_sched_job.s_fence of @job, so that it can be attached to struct dma_resv 820 * or other places that need to track the completion of this job. 821 * 822 * Refer to drm_sched_entity_push_job() documentation for locking 823 * considerations. 824 * 825 * This can only be called if drm_sched_job_init() succeeded. 826 */ 827 void drm_sched_job_arm(struct drm_sched_job *job) 828 { 829 struct drm_gpu_scheduler *sched; 830 struct drm_sched_entity *entity = job->entity; 831 832 BUG_ON(!entity); 833 drm_sched_entity_select_rq(entity); 834 sched = entity->rq->sched; 835 836 job->sched = sched; 837 job->s_priority = entity->priority; 838 job->id = atomic64_inc_return(&sched->job_id_count); 839 840 drm_sched_fence_init(job->s_fence, job->entity); 841 } 842 EXPORT_SYMBOL(drm_sched_job_arm); 843 844 /** 845 * drm_sched_job_add_dependency - adds the fence as a job dependency 846 * @job: scheduler job to add the dependencies to 847 * @fence: the dma_fence to add to the list of dependencies. 848 * 849 * Note that @fence is consumed in both the success and error cases. 850 * 851 * Returns: 852 * 0 on success, or an error on failing to expand the array. 853 */ 854 int drm_sched_job_add_dependency(struct drm_sched_job *job, 855 struct dma_fence *fence) 856 { 857 struct dma_fence *entry; 858 unsigned long index; 859 u32 id = 0; 860 int ret; 861 862 if (!fence) 863 return 0; 864 865 /* Deduplicate if we already depend on a fence from the same context. 866 * This lets the size of the array of deps scale with the number of 867 * engines involved, rather than the number of BOs. 868 */ 869 xa_for_each(&job->dependencies, index, entry) { 870 if (entry->context != fence->context) 871 continue; 872 873 if (dma_fence_is_later(fence, entry)) { 874 dma_fence_put(entry); 875 xa_store(&job->dependencies, index, fence, GFP_KERNEL); 876 } else { 877 dma_fence_put(fence); 878 } 879 return 0; 880 } 881 882 ret = xa_alloc(&job->dependencies, &id, fence, xa_limit_32b, GFP_KERNEL); 883 if (ret != 0) 884 dma_fence_put(fence); 885 886 return ret; 887 } 888 EXPORT_SYMBOL(drm_sched_job_add_dependency); 889 890 /** 891 * drm_sched_job_add_syncobj_dependency - adds a syncobj's fence as a job dependency 892 * @job: scheduler job to add the dependencies to 893 * @file: drm file private pointer 894 * @handle: syncobj handle to lookup 895 * @point: timeline point 896 * 897 * This adds the fence matching the given syncobj to @job. 898 * 899 * Returns: 900 * 0 on success, or an error on failing to expand the array. 901 */ 902 int drm_sched_job_add_syncobj_dependency(struct drm_sched_job *job, 903 struct drm_file *file, 904 u32 handle, 905 u32 point) 906 { 907 struct dma_fence *fence; 908 int ret; 909 910 ret = drm_syncobj_find_fence(file, handle, point, 0, &fence); 911 if (ret) 912 return ret; 913 914 return drm_sched_job_add_dependency(job, fence); 915 } 916 EXPORT_SYMBOL(drm_sched_job_add_syncobj_dependency); 917 918 /** 919 * drm_sched_job_add_resv_dependencies - add all fences from the resv to the job 920 * @job: scheduler job to add the dependencies to 921 * @resv: the dma_resv object to get the fences from 922 * @usage: the dma_resv_usage to use to filter the fences 923 * 924 * This adds all fences matching the given usage from @resv to @job. 925 * Must be called with the @resv lock held. 926 * 927 * Returns: 928 * 0 on success, or an error on failing to expand the array. 929 */ 930 int drm_sched_job_add_resv_dependencies(struct drm_sched_job *job, 931 struct dma_resv *resv, 932 enum dma_resv_usage usage) 933 { 934 struct dma_resv_iter cursor; 935 struct dma_fence *fence; 936 int ret; 937 938 dma_resv_assert_held(resv); 939 940 dma_resv_for_each_fence(&cursor, resv, usage, fence) { 941 /* Make sure to grab an additional ref on the added fence */ 942 dma_fence_get(fence); 943 ret = drm_sched_job_add_dependency(job, fence); 944 if (ret) { 945 dma_fence_put(fence); 946 return ret; 947 } 948 } 949 return 0; 950 } 951 EXPORT_SYMBOL(drm_sched_job_add_resv_dependencies); 952 953 /** 954 * drm_sched_job_add_implicit_dependencies - adds implicit dependencies as job 955 * dependencies 956 * @job: scheduler job to add the dependencies to 957 * @obj: the gem object to add new dependencies from. 958 * @write: whether the job might write the object (so we need to depend on 959 * shared fences in the reservation object). 960 * 961 * This should be called after drm_gem_lock_reservations() on your array of 962 * GEM objects used in the job but before updating the reservations with your 963 * own fences. 964 * 965 * Returns: 966 * 0 on success, or an error on failing to expand the array. 967 */ 968 int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job, 969 struct drm_gem_object *obj, 970 bool write) 971 { 972 return drm_sched_job_add_resv_dependencies(job, obj->resv, 973 dma_resv_usage_rw(write)); 974 } 975 EXPORT_SYMBOL(drm_sched_job_add_implicit_dependencies); 976 977 /** 978 * drm_sched_job_cleanup - clean up scheduler job resources 979 * @job: scheduler job to clean up 980 * 981 * Cleans up the resources allocated with drm_sched_job_init(). 982 * 983 * Drivers should call this from their error unwind code if @job is aborted 984 * before drm_sched_job_arm() is called. 985 * 986 * After that point of no return @job is committed to be executed by the 987 * scheduler, and this function should be called from the 988 * &drm_sched_backend_ops.free_job callback. 989 */ 990 void drm_sched_job_cleanup(struct drm_sched_job *job) 991 { 992 struct dma_fence *fence; 993 unsigned long index; 994 995 if (kref_read(&job->s_fence->finished.refcount)) { 996 /* drm_sched_job_arm() has been called */ 997 dma_fence_put(&job->s_fence->finished); 998 } else { 999 /* aborted job before committing to run it */ 1000 drm_sched_fence_free(job->s_fence); 1001 } 1002 1003 job->s_fence = NULL; 1004 1005 xa_for_each(&job->dependencies, index, fence) { 1006 dma_fence_put(fence); 1007 } 1008 xa_destroy(&job->dependencies); 1009 1010 } 1011 EXPORT_SYMBOL(drm_sched_job_cleanup); 1012 1013 /** 1014 * drm_sched_wakeup - Wake up the scheduler if it is ready to queue 1015 * @sched: scheduler instance 1016 * @entity: the scheduler entity 1017 * 1018 * Wake up the scheduler if we can queue jobs. 1019 */ 1020 void drm_sched_wakeup(struct drm_gpu_scheduler *sched, 1021 struct drm_sched_entity *entity) 1022 { 1023 if (drm_sched_can_queue(sched, entity)) 1024 drm_sched_run_job_queue(sched); 1025 } 1026 1027 /** 1028 * drm_sched_select_entity - Select next entity to process 1029 * 1030 * @sched: scheduler instance 1031 * 1032 * Return an entity to process or NULL if none are found. 1033 * 1034 * Note, that we break out of the for-loop when "entity" is non-null, which can 1035 * also be an error-pointer--this assures we don't process lower priority 1036 * run-queues. See comments in the respectively called functions. 1037 */ 1038 static struct drm_sched_entity * 1039 drm_sched_select_entity(struct drm_gpu_scheduler *sched) 1040 { 1041 struct drm_sched_entity *entity; 1042 int i; 1043 1044 /* Start with the highest priority. 1045 */ 1046 for (i = DRM_SCHED_PRIORITY_KERNEL; i < sched->num_rqs; i++) { 1047 entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ? 1048 drm_sched_rq_select_entity_fifo(sched, sched->sched_rq[i]) : 1049 drm_sched_rq_select_entity_rr(sched, sched->sched_rq[i]); 1050 if (entity) 1051 break; 1052 } 1053 1054 return IS_ERR(entity) ? NULL : entity; 1055 } 1056 1057 /** 1058 * drm_sched_get_finished_job - fetch the next finished job to be destroyed 1059 * 1060 * @sched: scheduler instance 1061 * 1062 * Returns the next finished job from the pending list (if there is one) 1063 * ready for it to be destroyed. 1064 */ 1065 static struct drm_sched_job * 1066 drm_sched_get_finished_job(struct drm_gpu_scheduler *sched) 1067 { 1068 struct drm_sched_job *job, *next; 1069 1070 spin_lock(&sched->job_list_lock); 1071 1072 job = list_first_entry_or_null(&sched->pending_list, 1073 struct drm_sched_job, list); 1074 1075 if (job && dma_fence_is_signaled(&job->s_fence->finished)) { 1076 /* remove job from pending_list */ 1077 list_del_init(&job->list); 1078 1079 /* cancel this job's TO timer */ 1080 cancel_delayed_work(&sched->work_tdr); 1081 /* make the scheduled timestamp more accurate */ 1082 next = list_first_entry_or_null(&sched->pending_list, 1083 typeof(*next), list); 1084 1085 if (next) { 1086 if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, 1087 &next->s_fence->scheduled.flags)) 1088 next->s_fence->scheduled.timestamp = 1089 dma_fence_timestamp(&job->s_fence->finished); 1090 /* start TO timer for next job */ 1091 drm_sched_start_timeout(sched); 1092 } 1093 } else { 1094 job = NULL; 1095 } 1096 1097 spin_unlock(&sched->job_list_lock); 1098 1099 return job; 1100 } 1101 1102 /** 1103 * drm_sched_pick_best - Get a drm sched from a sched_list with the least load 1104 * @sched_list: list of drm_gpu_schedulers 1105 * @num_sched_list: number of drm_gpu_schedulers in the sched_list 1106 * 1107 * Returns pointer of the sched with the least load or NULL if none of the 1108 * drm_gpu_schedulers are ready 1109 */ 1110 struct drm_gpu_scheduler * 1111 drm_sched_pick_best(struct drm_gpu_scheduler **sched_list, 1112 unsigned int num_sched_list) 1113 { 1114 struct drm_gpu_scheduler *sched, *picked_sched = NULL; 1115 int i; 1116 unsigned int min_score = UINT_MAX, num_score; 1117 1118 for (i = 0; i < num_sched_list; ++i) { 1119 sched = sched_list[i]; 1120 1121 if (!sched->ready) { 1122 DRM_WARN("scheduler %s is not ready, skipping", 1123 sched->name); 1124 continue; 1125 } 1126 1127 num_score = atomic_read(sched->score); 1128 if (num_score < min_score) { 1129 min_score = num_score; 1130 picked_sched = sched; 1131 } 1132 } 1133 1134 return picked_sched; 1135 } 1136 EXPORT_SYMBOL(drm_sched_pick_best); 1137 1138 /** 1139 * drm_sched_free_job_work - worker to call free_job 1140 * 1141 * @w: free job work 1142 */ 1143 static void drm_sched_free_job_work(struct work_struct *w) 1144 { 1145 struct drm_gpu_scheduler *sched = 1146 container_of(w, struct drm_gpu_scheduler, work_free_job); 1147 struct drm_sched_job *job; 1148 1149 if (READ_ONCE(sched->pause_submit)) 1150 return; 1151 1152 job = drm_sched_get_finished_job(sched); 1153 if (job) 1154 sched->ops->free_job(job); 1155 1156 drm_sched_run_free_queue(sched); 1157 drm_sched_run_job_queue(sched); 1158 } 1159 1160 /** 1161 * drm_sched_run_job_work - worker to call run_job 1162 * 1163 * @w: run job work 1164 */ 1165 static void drm_sched_run_job_work(struct work_struct *w) 1166 { 1167 struct drm_gpu_scheduler *sched = 1168 container_of(w, struct drm_gpu_scheduler, work_run_job); 1169 struct drm_sched_entity *entity; 1170 struct dma_fence *fence; 1171 struct drm_sched_fence *s_fence; 1172 struct drm_sched_job *sched_job; 1173 int r; 1174 1175 if (READ_ONCE(sched->pause_submit)) 1176 return; 1177 1178 /* Find entity with a ready job */ 1179 entity = drm_sched_select_entity(sched); 1180 if (!entity) 1181 return; /* No more work */ 1182 1183 sched_job = drm_sched_entity_pop_job(entity); 1184 if (!sched_job) { 1185 complete_all(&entity->entity_idle); 1186 drm_sched_run_job_queue(sched); 1187 return; 1188 } 1189 1190 s_fence = sched_job->s_fence; 1191 1192 atomic_add(sched_job->credits, &sched->credit_count); 1193 drm_sched_job_begin(sched_job); 1194 1195 trace_drm_run_job(sched_job, entity); 1196 fence = sched->ops->run_job(sched_job); 1197 complete_all(&entity->entity_idle); 1198 drm_sched_fence_scheduled(s_fence, fence); 1199 1200 if (!IS_ERR_OR_NULL(fence)) { 1201 /* Drop for original kref_init of the fence */ 1202 dma_fence_put(fence); 1203 1204 r = dma_fence_add_callback(fence, &sched_job->cb, 1205 drm_sched_job_done_cb); 1206 if (r == -ENOENT) 1207 drm_sched_job_done(sched_job, fence->error); 1208 else if (r) 1209 DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n", r); 1210 } else { 1211 drm_sched_job_done(sched_job, IS_ERR(fence) ? 1212 PTR_ERR(fence) : 0); 1213 } 1214 1215 wake_up(&sched->job_scheduled); 1216 drm_sched_run_job_queue(sched); 1217 } 1218 1219 /** 1220 * drm_sched_init - Init a gpu scheduler instance 1221 * 1222 * @sched: scheduler instance 1223 * @ops: backend operations for this scheduler 1224 * @submit_wq: workqueue to use for submission. If NULL, an ordered wq is 1225 * allocated and used 1226 * @num_rqs: number of runqueues, one for each priority, up to DRM_SCHED_PRIORITY_COUNT 1227 * @credit_limit: the number of credits this scheduler can hold from all jobs 1228 * @hang_limit: number of times to allow a job to hang before dropping it 1229 * @timeout: timeout value in jiffies for the scheduler 1230 * @timeout_wq: workqueue to use for timeout work. If NULL, the system_wq is 1231 * used 1232 * @score: optional score atomic shared with other schedulers 1233 * @name: name used for debugging 1234 * @dev: target &struct device 1235 * 1236 * Return 0 on success, otherwise error code. 1237 */ 1238 int drm_sched_init(struct drm_gpu_scheduler *sched, 1239 const struct drm_sched_backend_ops *ops, 1240 struct workqueue_struct *submit_wq, 1241 u32 num_rqs, u32 credit_limit, unsigned int hang_limit, 1242 long timeout, struct workqueue_struct *timeout_wq, 1243 atomic_t *score, const char *name, struct device *dev) 1244 { 1245 int i; 1246 1247 sched->ops = ops; 1248 sched->credit_limit = credit_limit; 1249 sched->name = name; 1250 sched->timeout = timeout; 1251 sched->timeout_wq = timeout_wq ? : system_wq; 1252 sched->hang_limit = hang_limit; 1253 sched->score = score ? score : &sched->_score; 1254 sched->dev = dev; 1255 1256 if (num_rqs > DRM_SCHED_PRIORITY_COUNT) { 1257 /* This is a gross violation--tell drivers what the problem is. 1258 */ 1259 drm_err(sched, "%s: num_rqs cannot be greater than DRM_SCHED_PRIORITY_COUNT\n", 1260 __func__); 1261 return -EINVAL; 1262 } else if (sched->sched_rq) { 1263 /* Not an error, but warn anyway so drivers can 1264 * fine-tune their DRM calling order, and return all 1265 * is good. 1266 */ 1267 drm_warn(sched, "%s: scheduler already initialized!\n", __func__); 1268 return 0; 1269 } 1270 1271 if (submit_wq) { 1272 sched->submit_wq = submit_wq; 1273 sched->own_submit_wq = false; 1274 } else { 1275 sched->submit_wq = alloc_ordered_workqueue(name, 0); 1276 if (!sched->submit_wq) 1277 return -ENOMEM; 1278 1279 sched->own_submit_wq = true; 1280 } 1281 1282 sched->sched_rq = kmalloc_array(num_rqs, sizeof(*sched->sched_rq), 1283 GFP_KERNEL | __GFP_ZERO); 1284 if (!sched->sched_rq) 1285 goto Out_check_own; 1286 sched->num_rqs = num_rqs; 1287 for (i = DRM_SCHED_PRIORITY_KERNEL; i < sched->num_rqs; i++) { 1288 sched->sched_rq[i] = kzalloc(sizeof(*sched->sched_rq[i]), GFP_KERNEL); 1289 if (!sched->sched_rq[i]) 1290 goto Out_unroll; 1291 drm_sched_rq_init(sched, sched->sched_rq[i]); 1292 } 1293 1294 init_waitqueue_head(&sched->job_scheduled); 1295 INIT_LIST_HEAD(&sched->pending_list); 1296 spin_lock_init(&sched->job_list_lock); 1297 atomic_set(&sched->credit_count, 0); 1298 INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout); 1299 INIT_WORK(&sched->work_run_job, drm_sched_run_job_work); 1300 INIT_WORK(&sched->work_free_job, drm_sched_free_job_work); 1301 atomic_set(&sched->_score, 0); 1302 atomic64_set(&sched->job_id_count, 0); 1303 sched->pause_submit = false; 1304 1305 sched->ready = true; 1306 return 0; 1307 Out_unroll: 1308 for (--i ; i >= DRM_SCHED_PRIORITY_KERNEL; i--) 1309 kfree(sched->sched_rq[i]); 1310 1311 kfree(sched->sched_rq); 1312 sched->sched_rq = NULL; 1313 Out_check_own: 1314 if (sched->own_submit_wq) 1315 destroy_workqueue(sched->submit_wq); 1316 drm_err(sched, "%s: Failed to setup GPU scheduler--out of memory\n", __func__); 1317 return -ENOMEM; 1318 } 1319 EXPORT_SYMBOL(drm_sched_init); 1320 1321 /** 1322 * drm_sched_fini - Destroy a gpu scheduler 1323 * 1324 * @sched: scheduler instance 1325 * 1326 * Tears down and cleans up the scheduler. 1327 */ 1328 void drm_sched_fini(struct drm_gpu_scheduler *sched) 1329 { 1330 struct drm_sched_entity *s_entity; 1331 int i; 1332 1333 drm_sched_wqueue_stop(sched); 1334 1335 for (i = DRM_SCHED_PRIORITY_KERNEL; i < sched->num_rqs; i++) { 1336 struct drm_sched_rq *rq = sched->sched_rq[i]; 1337 1338 spin_lock(&rq->lock); 1339 list_for_each_entry(s_entity, &rq->entities, list) 1340 /* 1341 * Prevents reinsertion and marks job_queue as idle, 1342 * it will removed from rq in drm_sched_entity_fini 1343 * eventually 1344 */ 1345 s_entity->stopped = true; 1346 spin_unlock(&rq->lock); 1347 kfree(sched->sched_rq[i]); 1348 } 1349 1350 /* Wakeup everyone stuck in drm_sched_entity_flush for this scheduler */ 1351 wake_up_all(&sched->job_scheduled); 1352 1353 /* Confirm no work left behind accessing device structures */ 1354 cancel_delayed_work_sync(&sched->work_tdr); 1355 1356 if (sched->own_submit_wq) 1357 destroy_workqueue(sched->submit_wq); 1358 sched->ready = false; 1359 kfree(sched->sched_rq); 1360 sched->sched_rq = NULL; 1361 } 1362 EXPORT_SYMBOL(drm_sched_fini); 1363 1364 /** 1365 * drm_sched_increase_karma - Update sched_entity guilty flag 1366 * 1367 * @bad: The job guilty of time out 1368 * 1369 * Increment on every hang caused by the 'bad' job. If this exceeds the hang 1370 * limit of the scheduler then the respective sched entity is marked guilty and 1371 * jobs from it will not be scheduled further 1372 */ 1373 void drm_sched_increase_karma(struct drm_sched_job *bad) 1374 { 1375 int i; 1376 struct drm_sched_entity *tmp; 1377 struct drm_sched_entity *entity; 1378 struct drm_gpu_scheduler *sched = bad->sched; 1379 1380 /* don't change @bad's karma if it's from KERNEL RQ, 1381 * because sometimes GPU hang would cause kernel jobs (like VM updating jobs) 1382 * corrupt but keep in mind that kernel jobs always considered good. 1383 */ 1384 if (bad->s_priority != DRM_SCHED_PRIORITY_KERNEL) { 1385 atomic_inc(&bad->karma); 1386 1387 for (i = DRM_SCHED_PRIORITY_HIGH; i < sched->num_rqs; i++) { 1388 struct drm_sched_rq *rq = sched->sched_rq[i]; 1389 1390 spin_lock(&rq->lock); 1391 list_for_each_entry_safe(entity, tmp, &rq->entities, list) { 1392 if (bad->s_fence->scheduled.context == 1393 entity->fence_context) { 1394 if (entity->guilty) 1395 atomic_set(entity->guilty, 1); 1396 break; 1397 } 1398 } 1399 spin_unlock(&rq->lock); 1400 if (&entity->list != &rq->entities) 1401 break; 1402 } 1403 } 1404 } 1405 EXPORT_SYMBOL(drm_sched_increase_karma); 1406 1407 /** 1408 * drm_sched_wqueue_ready - Is the scheduler ready for submission 1409 * 1410 * @sched: scheduler instance 1411 * 1412 * Returns true if submission is ready 1413 */ 1414 bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched) 1415 { 1416 return sched->ready; 1417 } 1418 EXPORT_SYMBOL(drm_sched_wqueue_ready); 1419 1420 /** 1421 * drm_sched_wqueue_stop - stop scheduler submission 1422 * 1423 * @sched: scheduler instance 1424 */ 1425 void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched) 1426 { 1427 WRITE_ONCE(sched->pause_submit, true); 1428 cancel_work_sync(&sched->work_run_job); 1429 cancel_work_sync(&sched->work_free_job); 1430 } 1431 EXPORT_SYMBOL(drm_sched_wqueue_stop); 1432 1433 /** 1434 * drm_sched_wqueue_start - start scheduler submission 1435 * 1436 * @sched: scheduler instance 1437 */ 1438 void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched) 1439 { 1440 WRITE_ONCE(sched->pause_submit, false); 1441 queue_work(sched->submit_wq, &sched->work_run_job); 1442 queue_work(sched->submit_wq, &sched->work_free_job); 1443 } 1444 EXPORT_SYMBOL(drm_sched_wqueue_start); 1445