include/drm/gpu_scheduler.h

   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 #ifndef _DRM_GPU_SCHEDULER_H_
  25 #define _DRM_GPU_SCHEDULER_H_
  26
  27 #include <drm/spsc_queue.h>
  28 #include <linux/dma-fence.h>
  29 #include <linux/completion.h>
  30
  31 #define MAX_WAIT_SCHED_ENTITY_Q_EMPTY msecs_to_jiffies(1000)
  32
  33 struct drm_gpu_scheduler;
  34 struct drm_sched_rq;
  35
  36 enum drm_sched_priority {
  37         DRM_SCHED_PRIORITY_MIN,
  38         DRM_SCHED_PRIORITY_LOW = DRM_SCHED_PRIORITY_MIN,
  39         DRM_SCHED_PRIORITY_NORMAL,
  40         DRM_SCHED_PRIORITY_HIGH_SW,
  41         DRM_SCHED_PRIORITY_HIGH_HW,
  42         DRM_SCHED_PRIORITY_KERNEL,
  43         DRM_SCHED_PRIORITY_MAX,
  44         DRM_SCHED_PRIORITY_INVALID = -1,
  45         DRM_SCHED_PRIORITY_UNSET = -2
  46 };
  47
  48 /**
  49  * struct drm_sched_entity - A wrapper around a job queue (typically
  50  * attached to the DRM file_priv).
  51  *
  52  * @list: used to append this struct to the list of entities in the
  53  *        runqueue.
  54  * @rq: runqueue on which this entity is currently scheduled.
  55  * @sched_list: a list of drm_gpu_schedulers on which jobs from this entity can
  56  *              be scheduled
  57  * @num_sched_list: number of drm_gpu_schedulers in the sched_list.
  58  * @rq_lock: lock to modify the runqueue to which this entity belongs.
  59  * @job_queue: the list of jobs of this entity.
  60  * @fence_seq: a linearly increasing seqno incremented with each
  61  *             new &drm_sched_fence which is part of the entity.
  62  * @fence_context: a unique context for all the fences which belong
  63  *                 to this entity.
  64  *                 The &drm_sched_fence.scheduled uses the
  65  *                 fence_context but &drm_sched_fence.finished uses
  66  *                 fence_context + 1.
  67  * @dependency: the dependency fence of the job which is on the top
  68  *              of the job queue.
  69  * @cb: callback for the dependency fence above.
  70  * @guilty: points to ctx's guilty.
  71  * @fini_status: contains the exit status in case the process was signalled.
  72  * @last_scheduled: points to the finished fence of the last scheduled job.
  73  * @last_user: last group leader pushing a job into the entity.
  74  * @stopped: Marks the enity as removed from rq and destined for termination.
  75  * @entity_idle: Signals when enityt is not in use
  76  *
  77  * Entities will emit jobs in order to their corresponding hardware
  78  * ring, and the scheduler will alternate between entities based on
  79  * scheduling policy.
  80  */
  81 struct drm_sched_entity {
  82         struct list_head                list;
  83         struct drm_sched_rq             *rq;
  84         struct drm_gpu_scheduler        **sched_list;
  85         unsigned int                    num_sched_list;
  86         enum drm_sched_priority         priority;
  87         spinlock_t                      rq_lock;
  88
  89         struct spsc_queue               job_queue;
  90
  91         atomic_t                        fence_seq;
  92         uint64_t                        fence_context;
  93
  94         struct dma_fence                *dependency;
  95         struct dma_fence_cb             cb;
  96         atomic_t                        *guilty;
  97         struct dma_fence                *last_scheduled;
  98         struct task_struct              *last_user;
  99         bool                            stopped;
 100         struct completion               entity_idle;
 101 };
 102
 103 /**
 104  * struct drm_sched_rq - queue of entities to be scheduled.
 105  *
 106  * @lock: to modify the entities list.
 107  * @sched: the scheduler to which this rq belongs to.
 108  * @entities: list of the entities to be scheduled.
 109  * @current_entity: the entity which is to be scheduled.
 110  *
 111  * Run queue is a set of entities scheduling command submissions for
 112  * one specific ring. It implements the scheduling policy that selects
 113  * the next entity to emit commands from.
 114  */
 115 struct drm_sched_rq {
 116         spinlock_t                      lock;
 117         struct drm_gpu_scheduler        *sched;
 118         struct list_head                entities;
 119         struct drm_sched_entity         *current_entity;
 120 };
 121
 122 /**
 123  * struct drm_sched_fence - fences corresponding to the scheduling of a job.
 124  */
 125 struct drm_sched_fence {
 126         /**
 127          * @scheduled: this fence is what will be signaled by the scheduler
 128          * when the job is scheduled.
 129          */
 130         struct dma_fence                scheduled;
 131
 132         /**
 133          * @finished: this fence is what will be signaled by the scheduler
 134          * when the job is completed.
 135          *
 136          * When setting up an out fence for the job, you should use
 137          * this, since it's available immediately upon
 138          * drm_sched_job_init(), and the fence returned by the driver
 139          * from run_job() won't be created until the dependencies have
 140          * resolved.
 141          */
 142         struct dma_fence                finished;
 143
 144         /**
 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.
 148          */
 149         struct dma_fence                *parent;
 150         /**
 151          * @sched: the scheduler instance to which the job having this struct
 152          * belongs to.
 153          */
 154         struct drm_gpu_scheduler        *sched;
 155         /**
 156          * @lock: the lock used by the scheduled and the finished fences.
 157          */
 158         spinlock_t                      lock;
 159         /**
 160          * @owner: job owner for debugging
 161          */
 162         void                            *owner;
 163 };
 164
 165 struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f);
 166
 167 /**
 168  * struct drm_sched_job - A job to be run by an entity.
 169  *
 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  * @node: used to append this struct to the @drm_gpu_scheduler.ring_mirror_list.
 175  * @id: a unique id assigned to each job scheduled on the scheduler.
 176  * @karma: increment on every hang caused by this job. If this exceeds the hang
 177  *         limit of the scheduler then the job is marked guilty and will not
 178  *         be scheduled further.
 179  * @s_priority: the priority of the job.
 180  * @entity: the entity to which this job belongs.
 181  * @cb: the callback for the parent fence in s_fence.
 182  *
 183  * A job is created by the driver using drm_sched_job_init(), and
 184  * should call drm_sched_entity_push_job() once it wants the scheduler
 185  * to schedule the job.
 186  */
 187 struct drm_sched_job {
 188         struct spsc_node                queue_node;
 189         struct drm_gpu_scheduler        *sched;
 190         struct drm_sched_fence          *s_fence;
 191         struct dma_fence_cb             finish_cb;
 192         struct list_head                node;
 193         uint64_t                        id;
 194         atomic_t                        karma;
 195         enum drm_sched_priority         s_priority;
 196         struct drm_sched_entity  *entity;
 197         struct dma_fence_cb             cb;
 198 };
 199
 200 static inline bool drm_sched_invalidate_job(struct drm_sched_job *s_job,
 201                                             int threshold)
 202 {
 203         return (s_job && atomic_inc_return(&s_job->karma) > threshold);
 204 }
 205
 206 /**
 207  * struct drm_sched_backend_ops
 208  *
 209  * Define the backend operations called by the scheduler,
 210  * these functions should be implemented in driver side.
 211  */
 212 struct drm_sched_backend_ops {
 213         /**
 214          * @dependency: Called when the scheduler is considering scheduling
 215          * this job next, to get another struct dma_fence for this job to
 216          * block on.  Once it returns NULL, run_job() may be called.
 217          */
 218         struct dma_fence *(*dependency)(struct drm_sched_job *sched_job,
 219                                         struct drm_sched_entity *s_entity);
 220
 221         /**
 222          * @run_job: Called to execute the job once all of the dependencies
 223          * have been resolved.  This may be called multiple times, if
 224          * timedout_job() has happened and drm_sched_job_recovery()
 225          * decides to try it again.
 226          */
 227         struct dma_fence *(*run_job)(struct drm_sched_job *sched_job);
 228
 229         /**
 230          * @timedout_job: Called when a job has taken too long to execute,
 231          * to trigger GPU recovery.
 232          */
 233         void (*timedout_job)(struct drm_sched_job *sched_job);
 234
 235         /**
 236          * @free_job: Called once the job's finished fence has been signaled
 237          * and it's time to clean it up.
 238          */
 239         void (*free_job)(struct drm_sched_job *sched_job);
 240 };
 241
 242 /**
 243  * struct drm_gpu_scheduler
 244  *
 245  * @ops: backend operations provided by the driver.
 246  * @hw_submission_limit: the max size of the hardware queue.
 247  * @timeout: the time after which a job is removed from the scheduler.
 248  * @name: name of the ring for which this scheduler is being used.
 249  * @sched_rq: priority wise array of run queues.
 250  * @wake_up_worker: the wait queue on which the scheduler sleeps until a job
 251  *                  is ready to be scheduled.
 252  * @job_scheduled: once @drm_sched_entity_do_release is called the scheduler
 253  *                 waits on this wait queue until all the scheduled jobs are
 254  *                 finished.
 255  * @hw_rq_count: the number of jobs currently in the hardware queue.
 256  * @job_id_count: used to assign unique id to the each job.
 257  * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
 258  *            timeout interval is over.
 259  * @thread: the kthread on which the scheduler which run.
 260  * @ring_mirror_list: the list of jobs which are currently in the job queue.
 261  * @job_list_lock: lock to protect the ring_mirror_list.
 262  * @hang_limit: once the hangs by a job crosses this limit then it is marked
 263  *              guilty and it will be considered for scheduling further.
 264  * @score: score to help loadbalancer pick a idle sched
 265  * @ready: marks if the underlying HW is ready to work
 266  * @free_guilty: A hit to time out handler to free the guilty job.
 267  *
 268  * One scheduler is implemented for each hardware ring.
 269  */
 270 struct drm_gpu_scheduler {
 271         const struct drm_sched_backend_ops      *ops;
 272         uint32_t                        hw_submission_limit;
 273         long                            timeout;
 274         const char                      *name;
 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;
 284         int                             hang_limit;
 285         atomic_t                        score;
 286         bool                            ready;
 287         bool                            free_guilty;
 288 };
 289
 290 int drm_sched_init(struct drm_gpu_scheduler *sched,
 291                    const struct drm_sched_backend_ops *ops,
 292                    uint32_t hw_submission, unsigned hang_limit, long timeout,
 293                    const char *name);
 294
 295 void drm_sched_fini(struct drm_gpu_scheduler *sched);
 296 int drm_sched_job_init(struct drm_sched_job *job,
 297                        struct drm_sched_entity *entity,
 298                        void *owner);
 299 void drm_sched_job_cleanup(struct drm_sched_job *job);
 300 void drm_sched_wakeup(struct drm_gpu_scheduler *sched);
 301 void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad);
 302 void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery);
 303 void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched);
 304 void drm_sched_increase_karma(struct drm_sched_job *bad);
 305 bool drm_sched_dependency_optimized(struct dma_fence* fence,
 306                                     struct drm_sched_entity *entity);
 307 void drm_sched_fault(struct drm_gpu_scheduler *sched);
 308 void drm_sched_job_kickout(struct drm_sched_job *s_job);
 309
 310 void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
 311                              struct drm_sched_entity *entity);
 312 void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
 313                                 struct drm_sched_entity *entity);
 314
 315 int drm_sched_entity_init(struct drm_sched_entity *entity,
 316                           enum drm_sched_priority priority,
 317                           struct drm_gpu_scheduler **sched_list,
 318                           unsigned int num_sched_list,
 319                           atomic_t *guilty);
 320 long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout);
 321 void drm_sched_entity_fini(struct drm_sched_entity *entity);
 322 void drm_sched_entity_destroy(struct drm_sched_entity *entity);
 323 void drm_sched_entity_select_rq(struct drm_sched_entity *entity);
 324 struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity);
 325 void drm_sched_entity_push_job(struct drm_sched_job *sched_job,
 326                                struct drm_sched_entity *entity);
 327 void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
 328                                    enum drm_sched_priority priority);
 329 bool drm_sched_entity_is_ready(struct drm_sched_entity *entity);
 330
 331 struct drm_sched_fence *drm_sched_fence_create(
 332         struct drm_sched_entity *s_entity, void *owner);
 333 void drm_sched_fence_scheduled(struct drm_sched_fence *fence);
 334 void drm_sched_fence_finished(struct drm_sched_fence *fence);
 335
 336 unsigned long drm_sched_suspend_timeout(struct drm_gpu_scheduler *sched);
 337 void drm_sched_resume_timeout(struct drm_gpu_scheduler *sched,
 338                                 unsigned long remaining);
 339
 340 #endif