2 * Copyright 2015 Advanced Micro Devices, Inc.
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:
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
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.
24 #include <linux/kthread.h>
25 #include <linux/wait.h>
26 #include <linux/sched.h>
28 #include "gpu_scheduler.h"
30 #define CREATE_TRACE_POINTS
31 #include "gpu_sched_trace.h"
33 static bool amd_sched_entity_is_ready(struct amd_sched_entity *entity);
34 static void amd_sched_wakeup(struct amd_gpu_scheduler *sched);
36 struct kmem_cache *sched_fence_slab;
37 atomic_t sched_fence_slab_ref = ATOMIC_INIT(0);
39 /* Initialize a given run queue struct */
40 static void amd_sched_rq_init(struct amd_sched_rq *rq)
42 spin_lock_init(&rq->lock);
43 INIT_LIST_HEAD(&rq->entities);
44 rq->current_entity = NULL;
47 static void amd_sched_rq_add_entity(struct amd_sched_rq *rq,
48 struct amd_sched_entity *entity)
51 list_add_tail(&entity->list, &rq->entities);
52 spin_unlock(&rq->lock);
55 static void amd_sched_rq_remove_entity(struct amd_sched_rq *rq,
56 struct amd_sched_entity *entity)
59 list_del_init(&entity->list);
60 if (rq->current_entity == entity)
61 rq->current_entity = NULL;
62 spin_unlock(&rq->lock);
66 * Select an entity which could provide a job to run
68 * @rq The run queue to check.
70 * Try to find a ready entity, returns NULL if none found.
72 static struct amd_sched_entity *
73 amd_sched_rq_select_entity(struct amd_sched_rq *rq)
75 struct amd_sched_entity *entity;
79 entity = rq->current_entity;
81 list_for_each_entry_continue(entity, &rq->entities, list) {
82 if (amd_sched_entity_is_ready(entity)) {
83 rq->current_entity = entity;
84 spin_unlock(&rq->lock);
90 list_for_each_entry(entity, &rq->entities, list) {
92 if (amd_sched_entity_is_ready(entity)) {
93 rq->current_entity = entity;
94 spin_unlock(&rq->lock);
98 if (entity == rq->current_entity)
102 spin_unlock(&rq->lock);
108 * Init a context entity used by scheduler when submit to HW ring.
110 * @sched The pointer to the scheduler
111 * @entity The pointer to a valid amd_sched_entity
112 * @rq The run queue this entity belongs
113 * @kernel If this is an entity for the kernel
114 * @jobs The max number of jobs in the job queue
116 * return 0 if succeed. negative error code on failure
118 int amd_sched_entity_init(struct amd_gpu_scheduler *sched,
119 struct amd_sched_entity *entity,
120 struct amd_sched_rq *rq,
125 if (!(sched && entity && rq))
128 memset(entity, 0, sizeof(struct amd_sched_entity));
129 INIT_LIST_HEAD(&entity->list);
131 entity->sched = sched;
133 spin_lock_init(&entity->queue_lock);
134 r = kfifo_alloc(&entity->job_queue, jobs * sizeof(void *), GFP_KERNEL);
138 atomic_set(&entity->fence_seq, 0);
139 entity->fence_context = fence_context_alloc(1);
141 /* Add the entity to the run queue */
142 amd_sched_rq_add_entity(rq, entity);
148 * Query if entity is initialized
150 * @sched Pointer to scheduler instance
151 * @entity The pointer to a valid scheduler entity
153 * return true if entity is initialized, false otherwise
155 static bool amd_sched_entity_is_initialized(struct amd_gpu_scheduler *sched,
156 struct amd_sched_entity *entity)
158 return entity->sched == sched &&
163 * Check if entity is idle
165 * @entity The pointer to a valid scheduler entity
167 * Return true if entity don't has any unscheduled jobs.
169 static bool amd_sched_entity_is_idle(struct amd_sched_entity *entity)
172 if (kfifo_is_empty(&entity->job_queue))
179 * Check if entity is ready
181 * @entity The pointer to a valid scheduler entity
183 * Return true if entity could provide a job.
185 static bool amd_sched_entity_is_ready(struct amd_sched_entity *entity)
187 if (kfifo_is_empty(&entity->job_queue))
190 if (ACCESS_ONCE(entity->dependency))
197 * Destroy a context entity
199 * @sched Pointer to scheduler instance
200 * @entity The pointer to a valid scheduler entity
202 * Cleanup and free the allocated resources.
204 void amd_sched_entity_fini(struct amd_gpu_scheduler *sched,
205 struct amd_sched_entity *entity)
207 struct amd_sched_rq *rq = entity->rq;
209 if (!amd_sched_entity_is_initialized(sched, entity))
213 * The client will not queue more IBs during this fini, consume existing
216 wait_event(sched->job_scheduled, amd_sched_entity_is_idle(entity));
218 amd_sched_rq_remove_entity(rq, entity);
219 kfifo_free(&entity->job_queue);
222 static void amd_sched_entity_wakeup(struct fence *f, struct fence_cb *cb)
224 struct amd_sched_entity *entity =
225 container_of(cb, struct amd_sched_entity, cb);
226 entity->dependency = NULL;
228 amd_sched_wakeup(entity->sched);
231 static bool amd_sched_entity_add_dependency_cb(struct amd_sched_entity *entity)
233 struct amd_gpu_scheduler *sched = entity->sched;
234 struct fence * fence = entity->dependency;
235 struct amd_sched_fence *s_fence;
237 if (fence->context == entity->fence_context) {
238 /* We can ignore fences from ourself */
239 fence_put(entity->dependency);
243 s_fence = to_amd_sched_fence(fence);
244 if (s_fence && s_fence->sched == sched) {
245 /* Fence is from the same scheduler */
246 if (test_bit(AMD_SCHED_FENCE_SCHEDULED_BIT, &fence->flags)) {
247 /* Ignore it when it is already scheduled */
248 fence_put(entity->dependency);
252 /* Wait for fence to be scheduled */
253 entity->cb.func = amd_sched_entity_wakeup;
254 list_add_tail(&entity->cb.node, &s_fence->scheduled_cb);
258 if (!fence_add_callback(entity->dependency, &entity->cb,
259 amd_sched_entity_wakeup))
262 fence_put(entity->dependency);
266 static struct amd_sched_job *
267 amd_sched_entity_pop_job(struct amd_sched_entity *entity)
269 struct amd_gpu_scheduler *sched = entity->sched;
270 struct amd_sched_job *sched_job;
272 if (!kfifo_out_peek(&entity->job_queue, &sched_job, sizeof(sched_job)))
275 while ((entity->dependency = sched->ops->dependency(sched_job)))
276 if (amd_sched_entity_add_dependency_cb(entity))
283 * Helper to submit a job to the job queue
285 * @sched_job The pointer to job required to submit
287 * Returns true if we could submit the job.
289 static bool amd_sched_entity_in(struct amd_sched_job *sched_job)
291 struct amd_sched_entity *entity = sched_job->s_entity;
292 bool added, first = false;
294 spin_lock(&entity->queue_lock);
295 added = kfifo_in(&entity->job_queue, &sched_job,
296 sizeof(sched_job)) == sizeof(sched_job);
298 if (added && kfifo_len(&entity->job_queue) == sizeof(sched_job))
301 spin_unlock(&entity->queue_lock);
303 /* first job wakes up scheduler */
305 amd_sched_wakeup(sched_job->sched);
311 * Submit a job to the job queue
313 * @sched_job The pointer to job required to submit
315 * Returns 0 for success, negative error code otherwise.
317 void amd_sched_entity_push_job(struct amd_sched_job *sched_job)
319 struct amd_sched_entity *entity = sched_job->s_entity;
321 wait_event(entity->sched->job_scheduled,
322 amd_sched_entity_in(sched_job));
323 trace_amd_sched_job(sched_job);
327 * Return ture if we can push more jobs to the hw.
329 static bool amd_sched_ready(struct amd_gpu_scheduler *sched)
331 return atomic_read(&sched->hw_rq_count) <
332 sched->hw_submission_limit;
336 * Wake up the scheduler when it is ready
338 static void amd_sched_wakeup(struct amd_gpu_scheduler *sched)
340 if (amd_sched_ready(sched))
341 wake_up_interruptible(&sched->wake_up_worker);
345 * Select next entity to process
347 static struct amd_sched_entity *
348 amd_sched_select_entity(struct amd_gpu_scheduler *sched)
350 struct amd_sched_entity *entity;
352 if (!amd_sched_ready(sched))
355 /* Kernel run queue has higher priority than normal run queue*/
356 entity = amd_sched_rq_select_entity(&sched->kernel_rq);
358 entity = amd_sched_rq_select_entity(&sched->sched_rq);
363 static void amd_sched_process_job(struct fence *f, struct fence_cb *cb)
365 struct amd_sched_fence *s_fence =
366 container_of(cb, struct amd_sched_fence, cb);
367 struct amd_gpu_scheduler *sched = s_fence->sched;
370 atomic_dec(&sched->hw_rq_count);
371 amd_sched_fence_signal(s_fence);
372 if (sched->timeout != MAX_SCHEDULE_TIMEOUT) {
373 cancel_delayed_work(&s_fence->dwork);
374 spin_lock_irqsave(&sched->fence_list_lock, flags);
375 list_del_init(&s_fence->list);
376 spin_unlock_irqrestore(&sched->fence_list_lock, flags);
378 trace_amd_sched_process_job(s_fence);
379 fence_put(&s_fence->base);
380 wake_up_interruptible(&sched->wake_up_worker);
383 static void amd_sched_fence_work_func(struct work_struct *work)
385 struct amd_sched_fence *s_fence =
386 container_of(work, struct amd_sched_fence, dwork.work);
387 struct amd_gpu_scheduler *sched = s_fence->sched;
388 struct amd_sched_fence *entity, *tmp;
391 DRM_ERROR("[%s] scheduler is timeout!\n", sched->name);
393 /* Clean all pending fences */
394 spin_lock_irqsave(&sched->fence_list_lock, flags);
395 list_for_each_entry_safe(entity, tmp, &sched->fence_list, list) {
396 DRM_ERROR(" fence no %d\n", entity->base.seqno);
397 cancel_delayed_work(&entity->dwork);
398 list_del_init(&entity->list);
399 fence_put(&entity->base);
401 spin_unlock_irqrestore(&sched->fence_list_lock, flags);
404 static int amd_sched_main(void *param)
406 struct sched_param sparam = {.sched_priority = 1};
407 struct amd_gpu_scheduler *sched = (struct amd_gpu_scheduler *)param;
410 spin_lock_init(&sched->fence_list_lock);
411 INIT_LIST_HEAD(&sched->fence_list);
412 sched_setscheduler(current, SCHED_FIFO, &sparam);
414 while (!kthread_should_stop()) {
415 struct amd_sched_entity *entity;
416 struct amd_sched_fence *s_fence;
417 struct amd_sched_job *sched_job;
421 wait_event_interruptible(sched->wake_up_worker,
422 (entity = amd_sched_select_entity(sched)) ||
423 kthread_should_stop());
428 sched_job = amd_sched_entity_pop_job(entity);
432 s_fence = sched_job->s_fence;
434 if (sched->timeout != MAX_SCHEDULE_TIMEOUT) {
435 INIT_DELAYED_WORK(&s_fence->dwork, amd_sched_fence_work_func);
436 schedule_delayed_work(&s_fence->dwork, sched->timeout);
437 spin_lock_irqsave(&sched->fence_list_lock, flags);
438 list_add_tail(&s_fence->list, &sched->fence_list);
439 spin_unlock_irqrestore(&sched->fence_list_lock, flags);
442 atomic_inc(&sched->hw_rq_count);
443 fence = sched->ops->run_job(sched_job);
444 amd_sched_fence_scheduled(s_fence);
446 r = fence_add_callback(fence, &s_fence->cb,
447 amd_sched_process_job);
449 amd_sched_process_job(fence, &s_fence->cb);
451 DRM_ERROR("fence add callback failed (%d)\n", r);
454 DRM_ERROR("Failed to run job!\n");
455 amd_sched_process_job(NULL, &s_fence->cb);
458 count = kfifo_out(&entity->job_queue, &sched_job,
460 WARN_ON(count != sizeof(sched_job));
461 wake_up(&sched->job_scheduled);
467 * Init a gpu scheduler instance
469 * @sched The pointer to the scheduler
470 * @ops The backend operations for this scheduler.
471 * @hw_submissions Number of hw submissions to do.
472 * @name Name used for debugging
474 * Return 0 on success, otherwise error code.
476 int amd_sched_init(struct amd_gpu_scheduler *sched,
477 struct amd_sched_backend_ops *ops,
478 unsigned hw_submission, long timeout, const char *name)
481 sched->hw_submission_limit = hw_submission;
483 sched->timeout = timeout;
484 amd_sched_rq_init(&sched->sched_rq);
485 amd_sched_rq_init(&sched->kernel_rq);
487 init_waitqueue_head(&sched->wake_up_worker);
488 init_waitqueue_head(&sched->job_scheduled);
489 atomic_set(&sched->hw_rq_count, 0);
490 if (atomic_inc_return(&sched_fence_slab_ref) == 1) {
491 sched_fence_slab = kmem_cache_create(
492 "amd_sched_fence", sizeof(struct amd_sched_fence), 0,
493 SLAB_HWCACHE_ALIGN, NULL);
494 if (!sched_fence_slab)
498 /* Each scheduler will run on a seperate kernel thread */
499 sched->thread = kthread_run(amd_sched_main, sched, sched->name);
500 if (IS_ERR(sched->thread)) {
501 DRM_ERROR("Failed to create scheduler for %s.\n", name);
502 return PTR_ERR(sched->thread);
509 * Destroy a gpu scheduler
511 * @sched The pointer to the scheduler
513 void amd_sched_fini(struct amd_gpu_scheduler *sched)
516 kthread_stop(sched->thread);
517 if (atomic_dec_and_test(&sched_fence_slab_ref))
518 kmem_cache_destroy(sched_fence_slab);