OSCL-LXR linux-6.0.1/​include/​drm/​gpu_scheduler.h	Source navigation Diff markup Identifier search General search
	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 /*
  * Copyright 2015 Advanced Micro Devices, Inc.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  * OTHER DEALINGS IN THE SOFTWARE.
  *
  */
 
 #ifndef _DRM_GPU_SCHEDULER_H_
 #define _DRM_GPU_SCHEDULER_H_
 
 #include <drm/spsc_queue.h>
 #include <linux/dma-fence.h>
 #include <linux/completion.h>
 #include <linux/xarray.h>
 #include <linux/workqueue.h>
 
 #define MAX_WAIT_SCHED_ENTITY_Q_EMPTY msecs_to_jiffies(1000)
 
 struct drm_gem_object;
 
 struct drm_gpu_scheduler;
 struct drm_sched_rq;
 
 /* These are often used as an (initial) index
  * to an array, and as such should start at 0.
  */
 enum drm_sched_priority {
     DRM_SCHED_PRIORITY_MIN,
     DRM_SCHED_PRIORITY_NORMAL,
     DRM_SCHED_PRIORITY_HIGH,
     DRM_SCHED_PRIORITY_KERNEL,
 
     DRM_SCHED_PRIORITY_COUNT,
     DRM_SCHED_PRIORITY_UNSET = -2
 };
 
 /**
  * struct drm_sched_entity - A wrapper around a job queue (typically
  * attached to the DRM file_priv).
  *
  * Entities will emit jobs in order to their corresponding hardware
  * ring, and the scheduler will alternate between entities based on
  * scheduling policy.
  */
 struct drm_sched_entity {
     /**
      * @list:
      *
      * Used to append this struct to the list of entities in the runqueue
      * @rq under &drm_sched_rq.entities.
      *
      * Protected by &drm_sched_rq.lock of @rq.
      */
     struct list_head        list;
 
     /**
      * @rq:
      *
      * Runqueue on which this entity is currently scheduled.
      *
      * FIXME: Locking is very unclear for this. Writers are protected by
      * @rq_lock, but readers are generally lockless and seem to just race
      * with not even a READ_ONCE.
      */
     struct drm_sched_rq     *rq;
 
     /**
      * @sched_list:
      *
      * A list of schedulers (struct drm_gpu_scheduler).  Jobs from this entity can
      * be scheduled on any scheduler on this list.
      *
      * This can be modified by calling drm_sched_entity_modify_sched().
      * Locking is entirely up to the driver, see the above function for more
      * details.
      *
      * This will be set to NULL if &num_sched_list equals 1 and @rq has been
      * set already.
      *
      * FIXME: This means priority changes through
      * drm_sched_entity_set_priority() will be lost henceforth in this case.
      */
     struct drm_gpu_scheduler        **sched_list;
 
     /**
      * @num_sched_list:
      *
      * Number of drm_gpu_schedulers in the @sched_list.
      */
     unsigned int                    num_sched_list;
 
     /**
      * @priority:
      *
      * Priority of the entity. This can be modified by calling
      * drm_sched_entity_set_priority(). Protected by &rq_lock.
      */
     enum drm_sched_priority         priority;
 
     /**
      * @rq_lock:
      *
      * Lock to modify the runqueue to which this entity belongs.
      */
     spinlock_t          rq_lock;
 
     /**
      * @job_queue: the list of jobs of this entity.
      */
     struct spsc_queue       job_queue;
 
     /**
      * @fence_seq:
      *
      * A linearly increasing seqno incremented with each new
      * &drm_sched_fence which is part of the entity.
      *
      * FIXME: Callers of drm_sched_job_arm() need to ensure correct locking,
      * this doesn't need to be atomic.
      */
     atomic_t            fence_seq;
 
     /**
      * @fence_context:
      *
      * A unique context for all the fences which belong to this entity.  The
      * &drm_sched_fence.scheduled uses the fence_context but
      * &drm_sched_fence.finished uses fence_context + 1.
      */
     uint64_t            fence_context;
 
     /**
      * @dependency:
      *
      * The dependency fence of the job which is on the top of the job queue.
      */
     struct dma_fence        *dependency;
 
     /**
      * @cb:
      *
      * Callback for the dependency fence above.
      */
     struct dma_fence_cb     cb;
 
     /**
      * @guilty:
      *
      * Points to entities' guilty.
      */
     atomic_t            *guilty;
 
     /**
      * @last_scheduled:
      *
      * Points to the finished fence of the last scheduled job. Only written
      * by the scheduler thread, can be accessed locklessly from
      * drm_sched_job_arm() iff the queue is empty.
      */
     struct dma_fence                *last_scheduled;
 
     /**
      * @last_user: last group leader pushing a job into the entity.
      */
     struct task_struct      *last_user;
 
     /**
      * @stopped:
      *
      * Marks the enity as removed from rq and destined for
      * termination. This is set by calling drm_sched_entity_flush() and by
      * drm_sched_fini().
      */
     bool                stopped;
 
     /**
      * @entity_idle:
      *
      * Signals when entity is not in use, used to sequence entity cleanup in
      * drm_sched_entity_fini().
      */
     struct completion       entity_idle;
 };
 
 /**
  * struct drm_sched_rq - queue of entities to be scheduled.
  *
  * @lock: to modify the entities list.
  * @sched: the scheduler to which this rq belongs to.
  * @entities: list of the entities to be scheduled.
  * @current_entity: the entity which is to be scheduled.
  *
  * Run queue is a set of entities scheduling command submissions for
  * one specific ring. It implements the scheduling policy that selects
  * the next entity to emit commands from.
  */
 struct drm_sched_rq {
     spinlock_t          lock;
     struct drm_gpu_scheduler    *sched;
     struct list_head        entities;
     struct drm_sched_entity     *current_entity;
 };
 
 /**
  * struct drm_sched_fence - fences corresponding to the scheduling of a job.
  */
 struct drm_sched_fence {
         /**
          * @scheduled: this fence is what will be signaled by the scheduler
          * when the job is scheduled.
          */
     struct dma_fence        scheduled;
 
         /**
          * @finished: this fence is what will be signaled by the scheduler
          * when the job is completed.
          *
          * When setting up an out fence for the job, you should use
          * this, since it's available immediately upon
          * drm_sched_job_init(), and the fence returned by the driver
          * from run_job() won't be created until the dependencies have
          * resolved.
          */
     struct dma_fence        finished;
 
         /**
          * @parent: the fence returned by &drm_sched_backend_ops.run_job
          * when scheduling the job on hardware. We signal the
          * &drm_sched_fence.finished fence once parent is signalled.
          */
     struct dma_fence        *parent;
         /**
          * @sched: the scheduler instance to which the job having this struct
          * belongs to.
          */
     struct drm_gpu_scheduler    *sched;
         /**
          * @lock: the lock used by the scheduled and the finished fences.
          */
     spinlock_t          lock;
         /**
          * @owner: job owner for debugging
          */
     void                *owner;
 };
 
 struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f);
 
 /**
  * struct drm_sched_job - A job to be run by an entity.
  *
  * @queue_node: used to append this struct to the queue of jobs in an entity.
  * @list: a job participates in a "pending" and "done" lists.
  * @sched: the scheduler instance on which this job is scheduled.
  * @s_fence: contains the fences for the scheduling of job.
  * @finish_cb: the callback for the finished fence.
  * @work: Helper to reschdeule job kill to different context.
  * @id: a unique id assigned to each job scheduled on the scheduler.
  * @karma: increment on every hang caused by this job. If this exceeds the hang
  *         limit of the scheduler then the job is marked guilty and will not
  *         be scheduled further.
  * @s_priority: the priority of the job.
  * @entity: the entity to which this job belongs.
  * @cb: the callback for the parent fence in s_fence.
  *
  * A job is created by the driver using drm_sched_job_init(), and
  * should call drm_sched_entity_push_job() once it wants the scheduler
  * to schedule the job.
  */
 struct drm_sched_job {
     struct spsc_node        queue_node;
     struct list_head        list;
     struct drm_gpu_scheduler    *sched;
     struct drm_sched_fence      *s_fence;
 
     /*
      * work is used only after finish_cb has been used and will not be
      * accessed anymore.
      */
     union {
         struct dma_fence_cb     finish_cb;
         struct work_struct      work;
     };
 
     uint64_t            id;
     atomic_t            karma;
     enum drm_sched_priority     s_priority;
     struct drm_sched_entity         *entity;
     struct dma_fence_cb     cb;
     /**
      * @dependencies:
      *
      * Contains the dependencies as struct dma_fence for this job, see
      * drm_sched_job_add_dependency() and
      * drm_sched_job_add_implicit_dependencies().
      */
     struct xarray           dependencies;
 
     /** @last_dependency: tracks @dependencies as they signal */
     unsigned long           last_dependency;
 };
 
 static inline bool drm_sched_invalidate_job(struct drm_sched_job *s_job,
                         int threshold)
 {
     return s_job && atomic_inc_return(&s_job->karma) > threshold;
 }
 
 enum drm_gpu_sched_stat {
     DRM_GPU_SCHED_STAT_NONE, /* Reserve 0 */
     DRM_GPU_SCHED_STAT_NOMINAL,
     DRM_GPU_SCHED_STAT_ENODEV,
 };
 
 /**
  * struct drm_sched_backend_ops
  *
  * Define the backend operations called by the scheduler,
  * these functions should be implemented in driver side.
  */
 struct drm_sched_backend_ops {
     /**
      * @dependency:
      *
      * Called when the scheduler is considering scheduling this job next, to
      * get another struct dma_fence for this job to block on.  Once it
      * returns NULL, run_job() may be called.
      *
      * If a driver exclusively uses drm_sched_job_add_dependency() and
      * drm_sched_job_add_implicit_dependencies() this can be ommitted and
      * left as NULL.
      */
     struct dma_fence *(*dependency)(struct drm_sched_job *sched_job,
                     struct drm_sched_entity *s_entity);
 
     /**
          * @run_job: Called to execute the job once all of the dependencies
          * have been resolved.  This may be called multiple times, if
      * timedout_job() has happened and drm_sched_job_recovery()
      * decides to try it again.
      */
     struct dma_fence *(*run_job)(struct drm_sched_job *sched_job);
 
     /**
      * @timedout_job: Called when a job has taken too long to execute,
      * to trigger GPU recovery.
      *
      * This method is called in a workqueue context.
      *
      * Drivers typically issue a reset to recover from GPU hangs, and this
      * procedure usually follows the following workflow:
      *
      * 1. Stop the scheduler using drm_sched_stop(). This will park the
      *    scheduler thread and cancel the timeout work, guaranteeing that
      *    nothing is queued while we reset the hardware queue
      * 2. Try to gracefully stop non-faulty jobs (optional)
      * 3. Issue a GPU reset (driver-specific)
      * 4. Re-submit jobs using drm_sched_resubmit_jobs()
      * 5. Restart the scheduler using drm_sched_start(). At that point, new
      *    jobs can be queued, and the scheduler thread is unblocked
      *
      * Note that some GPUs have distinct hardware queues but need to reset
      * the GPU globally, which requires extra synchronization between the
      * timeout handler of the different &drm_gpu_scheduler. One way to
      * achieve this synchronization is to create an ordered workqueue
      * (using alloc_ordered_workqueue()) at the driver level, and pass this
      * queue to drm_sched_init(), to guarantee that timeout handlers are
      * executed sequentially. The above workflow needs to be slightly
      * adjusted in that case:
      *
      * 1. Stop all schedulers impacted by the reset using drm_sched_stop()
      * 2. Try to gracefully stop non-faulty jobs on all queues impacted by
      *    the reset (optional)
      * 3. Issue a GPU reset on all faulty queues (driver-specific)
      * 4. Re-submit jobs on all schedulers impacted by the reset using
      *    drm_sched_resubmit_jobs()
      * 5. Restart all schedulers that were stopped in step #1 using
      *    drm_sched_start()
      *
      * Return DRM_GPU_SCHED_STAT_NOMINAL, when all is normal,
      * and the underlying driver has started or completed recovery.
      *
      * Return DRM_GPU_SCHED_STAT_ENODEV, if the device is no longer
      * available, i.e. has been unplugged.
      */
     enum drm_gpu_sched_stat (*timedout_job)(struct drm_sched_job *sched_job);
 
     /**
          * @free_job: Called once the job's finished fence has been signaled
          * and it's time to clean it up.
      */
     void (*free_job)(struct drm_sched_job *sched_job);
 };
 
 /**
  * struct drm_gpu_scheduler
  *
  * @ops: backend operations provided by the driver.
  * @hw_submission_limit: the max size of the hardware queue.
  * @timeout: the time after which a job is removed from the scheduler.
  * @name: name of the ring for which this scheduler is being used.
  * @sched_rq: priority wise array of run queues.
  * @wake_up_worker: the wait queue on which the scheduler sleeps until a job
  *                  is ready to be scheduled.
  * @job_scheduled: once @drm_sched_entity_do_release is called the scheduler
  *                 waits on this wait queue until all the scheduled jobs are
  *                 finished.
  * @hw_rq_count: the number of jobs currently in the hardware queue.
  * @job_id_count: used to assign unique id to the each job.
  * @timeout_wq: workqueue used to queue @work_tdr
  * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
  *            timeout interval is over.
  * @thread: the kthread on which the scheduler which run.
  * @pending_list: the list of jobs which are currently in the job queue.
  * @job_list_lock: lock to protect the pending_list.
  * @hang_limit: once the hangs by a job crosses this limit then it is marked
  *              guilty and it will no longer be considered for scheduling.
  * @score: score to help loadbalancer pick a idle sched
  * @_score: score used when the driver doesn't provide one
  * @ready: marks if the underlying HW is ready to work
  * @free_guilty: A hit to time out handler to free the guilty job.
  *
  * One scheduler is implemented for each hardware ring.
  */
 struct drm_gpu_scheduler {
     const struct drm_sched_backend_ops  *ops;
     uint32_t            hw_submission_limit;
     long                timeout;
     const char          *name;
     struct drm_sched_rq     sched_rq[DRM_SCHED_PRIORITY_COUNT];
     wait_queue_head_t       wake_up_worker;
     wait_queue_head_t       job_scheduled;
     atomic_t            hw_rq_count;
     atomic64_t          job_id_count;
     struct workqueue_struct     *timeout_wq;
     struct delayed_work     work_tdr;
     struct task_struct      *thread;
     struct list_head        pending_list;
     spinlock_t          job_list_lock;
     int             hang_limit;
     atomic_t                        *score;
     atomic_t                        _score;
     bool                ready;
     bool                free_guilty;
     struct device           *dev;
 };
 
 int drm_sched_init(struct drm_gpu_scheduler *sched,
            const struct drm_sched_backend_ops *ops,
            uint32_t hw_submission, unsigned hang_limit,
            long timeout, struct workqueue_struct *timeout_wq,
            atomic_t *score, const char *name, struct device *dev);
 
 void drm_sched_fini(struct drm_gpu_scheduler *sched);
 int drm_sched_job_init(struct drm_sched_job *job,
                struct drm_sched_entity *entity,
                void *owner);
 void drm_sched_job_arm(struct drm_sched_job *job);
 int drm_sched_job_add_dependency(struct drm_sched_job *job,
                  struct dma_fence *fence);
 int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job,
                         struct drm_gem_object *obj,
                         bool write);
 
 
 void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
                     struct drm_gpu_scheduler **sched_list,
                                    unsigned int num_sched_list);
 
 void drm_sched_job_cleanup(struct drm_sched_job *job);
 void drm_sched_wakeup(struct drm_gpu_scheduler *sched);
 void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad);
 void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery);
 void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched);
 void drm_sched_resubmit_jobs_ext(struct drm_gpu_scheduler *sched, int max);
 void drm_sched_increase_karma(struct drm_sched_job *bad);
 void drm_sched_reset_karma(struct drm_sched_job *bad);
 void drm_sched_increase_karma_ext(struct drm_sched_job *bad, int type);
 bool drm_sched_dependency_optimized(struct dma_fence* fence,
                     struct drm_sched_entity *entity);
 void drm_sched_fault(struct drm_gpu_scheduler *sched);
 void drm_sched_job_kickout(struct drm_sched_job *s_job);
 
 void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
                  struct drm_sched_entity *entity);
 void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
                 struct drm_sched_entity *entity);
 
 int drm_sched_entity_init(struct drm_sched_entity *entity,
               enum drm_sched_priority priority,
               struct drm_gpu_scheduler **sched_list,
               unsigned int num_sched_list,
               atomic_t *guilty);
 long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout);
 void drm_sched_entity_fini(struct drm_sched_entity *entity);
 void drm_sched_entity_destroy(struct drm_sched_entity *entity);
 void drm_sched_entity_select_rq(struct drm_sched_entity *entity);
 struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity);
 void drm_sched_entity_push_job(struct drm_sched_job *sched_job);
 void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
                    enum drm_sched_priority priority);
 bool drm_sched_entity_is_ready(struct drm_sched_entity *entity);
 
 struct drm_sched_fence *drm_sched_fence_alloc(
     struct drm_sched_entity *s_entity, void *owner);
 void drm_sched_fence_init(struct drm_sched_fence *fence,
               struct drm_sched_entity *entity);
 void drm_sched_fence_free(struct drm_sched_fence *fence);
 
 void drm_sched_fence_scheduled(struct drm_sched_fence *fence);
 void drm_sched_fence_finished(struct drm_sched_fence *fence);
 
 unsigned long drm_sched_suspend_timeout(struct drm_gpu_scheduler *sched);
 void drm_sched_resume_timeout(struct drm_gpu_scheduler *sched,
                         unsigned long remaining);
 struct drm_gpu_scheduler *
 drm_sched_pick_best(struct drm_gpu_scheduler **sched_list,
              unsigned int num_sched_list);
 
 #endif

This page was automatically generated by the 2.1.0 LXR engine. The LXR team