2 * Copyright 2015 Advanced Micro Devices, Inc.
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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
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24 #ifndef _DRM_GPU_SCHEDULER_H_
25 #define _DRM_GPU_SCHEDULER_H_
27 #include <drm/spsc_queue.h>
28 #include <linux/dma-fence.h>
30 #define MAX_WAIT_SCHED_ENTITY_Q_EMPTY msecs_to_jiffies(1000)
32 struct drm_gpu_scheduler;
35 enum drm_sched_priority {
36 DRM_SCHED_PRIORITY_MIN,
37 DRM_SCHED_PRIORITY_LOW = DRM_SCHED_PRIORITY_MIN,
38 DRM_SCHED_PRIORITY_NORMAL,
39 DRM_SCHED_PRIORITY_HIGH_SW,
40 DRM_SCHED_PRIORITY_HIGH_HW,
41 DRM_SCHED_PRIORITY_KERNEL,
42 DRM_SCHED_PRIORITY_MAX,
43 DRM_SCHED_PRIORITY_INVALID = -1,
44 DRM_SCHED_PRIORITY_UNSET = -2
48 * struct drm_sched_entity - A wrapper around a job queue (typically
49 * attached to the DRM file_priv).
51 * @list: used to append this struct to the list of entities in the
53 * @rq: runqueue on which this entity is currently scheduled.
54 * @rq_list: a list of run queues on which jobs from this entity can
56 * @num_rq_list: number of run queues in the rq_list
57 * @rq_lock: lock to modify the runqueue to which this entity belongs.
58 * @job_queue: the list of jobs of this entity.
59 * @fence_seq: a linearly increasing seqno incremented with each
60 * new &drm_sched_fence which is part of the entity.
61 * @fence_context: a unique context for all the fences which belong
63 * The &drm_sched_fence.scheduled uses the
64 * fence_context but &drm_sched_fence.finished uses
66 * @dependency: the dependency fence of the job which is on the top
68 * @cb: callback for the dependency fence above.
69 * @guilty: points to ctx's guilty.
70 * @fini_status: contains the exit status in case the process was signalled.
71 * @last_scheduled: points to the finished fence of the last scheduled job.
72 * @last_user: last group leader pushing a job into the entity.
73 * @stopped: Marks the enity as removed from rq and destined for termination.
75 * Entities will emit jobs in order to their corresponding hardware
76 * ring, and the scheduler will alternate between entities based on
79 struct drm_sched_entity {
80 struct list_head list;
81 struct drm_sched_rq *rq;
82 struct drm_sched_rq **rq_list;
83 unsigned int num_rq_list;
86 struct spsc_queue job_queue;
89 uint64_t fence_context;
91 struct dma_fence *dependency;
92 struct dma_fence_cb cb;
94 struct dma_fence *last_scheduled;
95 struct task_struct *last_user;
100 * struct drm_sched_rq - queue of entities to be scheduled.
102 * @lock: to modify the entities list.
103 * @sched: the scheduler to which this rq belongs to.
104 * @entities: list of the entities to be scheduled.
105 * @current_entity: the entity which is to be scheduled.
107 * Run queue is a set of entities scheduling command submissions for
108 * one specific ring. It implements the scheduling policy that selects
109 * the next entity to emit commands from.
111 struct drm_sched_rq {
113 struct drm_gpu_scheduler *sched;
114 struct list_head entities;
115 struct drm_sched_entity *current_entity;
119 * struct drm_sched_fence - fences corresponding to the scheduling of a job.
121 struct drm_sched_fence {
123 * @scheduled: this fence is what will be signaled by the scheduler
124 * when the job is scheduled.
126 struct dma_fence scheduled;
129 * @finished: this fence is what will be signaled by the scheduler
130 * when the job is completed.
132 * When setting up an out fence for the job, you should use
133 * this, since it's available immediately upon
134 * drm_sched_job_init(), and the fence returned by the driver
135 * from run_job() won't be created until the dependencies have
138 struct dma_fence finished;
141 * @cb: the callback for the parent fence below.
143 struct dma_fence_cb cb;
145 * @parent: the fence returned by &drm_sched_backend_ops.run_job
146 * when scheduling the job on hardware. We signal the
147 * &drm_sched_fence.finished fence once parent is signalled.
149 struct dma_fence *parent;
151 * @sched: the scheduler instance to which the job having this struct
154 struct drm_gpu_scheduler *sched;
156 * @lock: the lock used by the scheduled and the finished fences.
160 * @owner: job owner for debugging
165 struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f);
168 * struct drm_sched_job - A job to be run by an entity.
170 * @queue_node: used to append this struct to the queue of jobs in an entity.
171 * @sched: the scheduler instance on which this job is scheduled.
172 * @s_fence: contains the fences for the scheduling of job.
173 * @finish_cb: the callback for the finished fence.
174 * @finish_work: schedules the function @drm_sched_job_finish once the job has
175 * finished to remove the job from the
176 * @drm_gpu_scheduler.ring_mirror_list.
177 * @node: used to append this struct to the @drm_gpu_scheduler.ring_mirror_list.
178 * @id: a unique id assigned to each job scheduled on the scheduler.
179 * @karma: increment on every hang caused by this job. If this exceeds the hang
180 * limit of the scheduler then the job is marked guilty and will not
181 * be scheduled further.
182 * @s_priority: the priority of the job.
183 * @entity: the entity to which this job belongs.
185 * A job is created by the driver using drm_sched_job_init(), and
186 * should call drm_sched_entity_push_job() once it wants the scheduler
187 * to schedule the job.
189 struct drm_sched_job {
190 struct spsc_node queue_node;
191 struct drm_gpu_scheduler *sched;
192 struct drm_sched_fence *s_fence;
193 struct dma_fence_cb finish_cb;
194 struct work_struct finish_work;
195 struct list_head node;
198 enum drm_sched_priority s_priority;
199 struct drm_sched_entity *entity;
202 static inline bool drm_sched_invalidate_job(struct drm_sched_job *s_job,
205 return (s_job && atomic_inc_return(&s_job->karma) > threshold);
209 * struct drm_sched_backend_ops
211 * Define the backend operations called by the scheduler,
212 * these functions should be implemented in driver side.
214 struct drm_sched_backend_ops {
216 * @dependency: Called when the scheduler is considering scheduling
217 * this job next, to get another struct dma_fence for this job to
218 * block on. Once it returns NULL, run_job() may be called.
220 struct dma_fence *(*dependency)(struct drm_sched_job *sched_job,
221 struct drm_sched_entity *s_entity);
224 * @run_job: Called to execute the job once all of the dependencies
225 * have been resolved. This may be called multiple times, if
226 * timedout_job() has happened and drm_sched_job_recovery()
227 * decides to try it again.
229 struct dma_fence *(*run_job)(struct drm_sched_job *sched_job);
232 * @timedout_job: Called when a job has taken too long to execute,
233 * to trigger GPU recovery.
235 void (*timedout_job)(struct drm_sched_job *sched_job);
238 * @free_job: Called once the job's finished fence has been signaled
239 * and it's time to clean it up.
241 void (*free_job)(struct drm_sched_job *sched_job);
245 * struct drm_gpu_scheduler
247 * @ops: backend operations provided by the driver.
248 * @hw_submission_limit: the max size of the hardware queue.
249 * @timeout: the time after which a job is removed from the scheduler.
250 * @name: name of the ring for which this scheduler is being used.
251 * @sched_rq: priority wise array of run queues.
252 * @wake_up_worker: the wait queue on which the scheduler sleeps until a job
253 * is ready to be scheduled.
254 * @job_scheduled: once @drm_sched_entity_do_release is called the scheduler
255 * waits on this wait queue until all the scheduled jobs are
257 * @hw_rq_count: the number of jobs currently in the hardware queue.
258 * @job_id_count: used to assign unique id to the each job.
259 * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
260 * timeout interval is over.
261 * @thread: the kthread on which the scheduler which run.
262 * @ring_mirror_list: the list of jobs which are currently in the job queue.
263 * @job_list_lock: lock to protect the ring_mirror_list.
264 * @hang_limit: once the hangs by a job crosses this limit then it is marked
265 * guilty and it will be considered for scheduling further.
266 * @num_jobs: the number of jobs in queue in the scheduler
268 * One scheduler is implemented for each hardware ring.
270 struct drm_gpu_scheduler {
271 const struct drm_sched_backend_ops *ops;
272 uint32_t hw_submission_limit;
275 struct drm_sched_rq sched_rq[DRM_SCHED_PRIORITY_MAX];
276 wait_queue_head_t wake_up_worker;
277 wait_queue_head_t job_scheduled;
278 atomic_t hw_rq_count;
279 atomic64_t job_id_count;
280 struct delayed_work work_tdr;
281 struct task_struct *thread;
282 struct list_head ring_mirror_list;
283 spinlock_t job_list_lock;
288 int drm_sched_init(struct drm_gpu_scheduler *sched,
289 const struct drm_sched_backend_ops *ops,
290 uint32_t hw_submission, unsigned hang_limit, long timeout,
292 void drm_sched_fini(struct drm_gpu_scheduler *sched);
293 int drm_sched_job_init(struct drm_sched_job *job,
294 struct drm_sched_entity *entity,
296 void drm_sched_wakeup(struct drm_gpu_scheduler *sched);
297 void drm_sched_hw_job_reset(struct drm_gpu_scheduler *sched,
298 struct drm_sched_job *job);
299 void drm_sched_job_recovery(struct drm_gpu_scheduler *sched);
300 bool drm_sched_dependency_optimized(struct dma_fence* fence,
301 struct drm_sched_entity *entity);
302 void drm_sched_job_kickout(struct drm_sched_job *s_job);
304 void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
305 struct drm_sched_entity *entity);
306 void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
307 struct drm_sched_entity *entity);
309 int drm_sched_entity_init(struct drm_sched_entity *entity,
310 struct drm_sched_rq **rq_list,
311 unsigned int num_rq_list,
313 long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout);
314 void drm_sched_entity_fini(struct drm_sched_entity *entity);
315 void drm_sched_entity_destroy(struct drm_sched_entity *entity);
316 void drm_sched_entity_select_rq(struct drm_sched_entity *entity);
317 struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity);
318 void drm_sched_entity_push_job(struct drm_sched_job *sched_job,
319 struct drm_sched_entity *entity);
320 void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
321 enum drm_sched_priority priority);
322 bool drm_sched_entity_is_ready(struct drm_sched_entity *entity);
324 struct drm_sched_fence *drm_sched_fence_create(
325 struct drm_sched_entity *s_entity, void *owner);
326 void drm_sched_fence_scheduled(struct drm_sched_fence *fence);
327 void drm_sched_fence_finished(struct drm_sched_fence *fence);