diff options
Diffstat (limited to 'drivers/gpu/drm/amd/scheduler/gpu_scheduler.c')
-rw-r--r-- | drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 423 |
1 files changed, 423 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c new file mode 100644 index 000000000000..ab8577f8ed4a --- /dev/null +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c @@ -0,0 +1,423 @@ +/* + * 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. + * + * + */ +#include <linux/kthread.h> +#include <linux/wait.h> +#include <linux/sched.h> +#include <drm/drmP.h> +#include "gpu_scheduler.h" + +static struct amd_sched_job * +amd_sched_entity_pop_job(struct amd_sched_entity *entity); +static void amd_sched_wakeup(struct amd_gpu_scheduler *sched); + +/* Initialize a given run queue struct */ +static void amd_sched_rq_init(struct amd_sched_rq *rq) +{ + spin_lock_init(&rq->lock); + INIT_LIST_HEAD(&rq->entities); + rq->current_entity = NULL; +} + +static void amd_sched_rq_add_entity(struct amd_sched_rq *rq, + struct amd_sched_entity *entity) +{ + spin_lock(&rq->lock); + list_add_tail(&entity->list, &rq->entities); + spin_unlock(&rq->lock); +} + +static void amd_sched_rq_remove_entity(struct amd_sched_rq *rq, + struct amd_sched_entity *entity) +{ + spin_lock(&rq->lock); + list_del_init(&entity->list); + if (rq->current_entity == entity) + rq->current_entity = NULL; + spin_unlock(&rq->lock); +} + +/** + * Select next job from a specified run queue with round robin policy. + * Return NULL if nothing available. + */ +static struct amd_sched_job * +amd_sched_rq_select_job(struct amd_sched_rq *rq) +{ + struct amd_sched_entity *entity; + struct amd_sched_job *job; + + spin_lock(&rq->lock); + + entity = rq->current_entity; + if (entity) { + list_for_each_entry_continue(entity, &rq->entities, list) { + job = amd_sched_entity_pop_job(entity); + if (job) { + rq->current_entity = entity; + spin_unlock(&rq->lock); + return job; + } + } + } + + list_for_each_entry(entity, &rq->entities, list) { + + job = amd_sched_entity_pop_job(entity); + if (job) { + rq->current_entity = entity; + spin_unlock(&rq->lock); + return job; + } + + if (entity == rq->current_entity) + break; + } + + spin_unlock(&rq->lock); + + return NULL; +} + +/** + * Init a context entity used by scheduler when submit to HW ring. + * + * @sched The pointer to the scheduler + * @entity The pointer to a valid amd_sched_entity + * @rq The run queue this entity belongs + * @kernel If this is an entity for the kernel + * @jobs The max number of jobs in the job queue + * + * return 0 if succeed. negative error code on failure +*/ +int amd_sched_entity_init(struct amd_gpu_scheduler *sched, + struct amd_sched_entity *entity, + struct amd_sched_rq *rq, + uint32_t jobs) +{ + if (!(sched && entity && rq)) + return -EINVAL; + + memset(entity, 0, sizeof(struct amd_sched_entity)); + entity->belongto_rq = rq; + entity->scheduler = sched; + entity->fence_context = fence_context_alloc(1); + if(kfifo_alloc(&entity->job_queue, + jobs * sizeof(void *), + GFP_KERNEL)) + return -EINVAL; + + spin_lock_init(&entity->queue_lock); + atomic_set(&entity->fence_seq, 0); + + /* Add the entity to the run queue */ + amd_sched_rq_add_entity(rq, entity); + return 0; +} + +/** + * Query if entity is initialized + * + * @sched Pointer to scheduler instance + * @entity The pointer to a valid scheduler entity + * + * return true if entity is initialized, false otherwise +*/ +static bool amd_sched_entity_is_initialized(struct amd_gpu_scheduler *sched, + struct amd_sched_entity *entity) +{ + return entity->scheduler == sched && + entity->belongto_rq != NULL; +} + +/** + * Check if entity is idle + * + * @entity The pointer to a valid scheduler entity + * + * Return true if entity don't has any unscheduled jobs. + */ +static bool amd_sched_entity_is_idle(struct amd_sched_entity *entity) +{ + rmb(); + if (kfifo_is_empty(&entity->job_queue)) + return true; + + return false; +} + +/** + * Destroy a context entity + * + * @sched Pointer to scheduler instance + * @entity The pointer to a valid scheduler entity + * + * Cleanup and free the allocated resources. + */ +void amd_sched_entity_fini(struct amd_gpu_scheduler *sched, + struct amd_sched_entity *entity) +{ + struct amd_sched_rq *rq = entity->belongto_rq; + + if (!amd_sched_entity_is_initialized(sched, entity)) + return; + + /** + * The client will not queue more IBs during this fini, consume existing + * queued IBs + */ + wait_event(sched->job_scheduled, amd_sched_entity_is_idle(entity)); + + amd_sched_rq_remove_entity(rq, entity); + kfifo_free(&entity->job_queue); +} + +static void amd_sched_entity_wakeup(struct fence *f, struct fence_cb *cb) +{ + struct amd_sched_entity *entity = + container_of(cb, struct amd_sched_entity, cb); + entity->dependency = NULL; + fence_put(f); + amd_sched_wakeup(entity->scheduler); +} + +static struct amd_sched_job * +amd_sched_entity_pop_job(struct amd_sched_entity *entity) +{ + struct amd_gpu_scheduler *sched = entity->scheduler; + struct amd_sched_job *job; + + if (ACCESS_ONCE(entity->dependency)) + return NULL; + + if (!kfifo_out_peek(&entity->job_queue, &job, sizeof(job))) + return NULL; + + while ((entity->dependency = sched->ops->dependency(job))) { + + if (fence_add_callback(entity->dependency, &entity->cb, + amd_sched_entity_wakeup)) + fence_put(entity->dependency); + else + return NULL; + } + + return job; +} + +/** + * Helper to submit a job to the job queue + * + * @job The pointer to job required to submit + * + * Returns true if we could submit the job. + */ +static bool amd_sched_entity_in(struct amd_sched_job *job) +{ + struct amd_sched_entity *entity = job->s_entity; + bool added, first = false; + + spin_lock(&entity->queue_lock); + added = kfifo_in(&entity->job_queue, &job, sizeof(job)) == sizeof(job); + + if (added && kfifo_len(&entity->job_queue) == sizeof(job)) + first = true; + + spin_unlock(&entity->queue_lock); + + /* first job wakes up scheduler */ + if (first) + amd_sched_wakeup(job->sched); + + return added; +} + +/** + * Submit a job to the job queue + * + * @job The pointer to job required to submit + * + * Returns 0 for success, negative error code otherwise. + */ +int amd_sched_entity_push_job(struct amd_sched_job *sched_job) +{ + struct amd_sched_entity *entity = sched_job->s_entity; + struct amd_sched_fence *fence = amd_sched_fence_create( + entity, sched_job->owner); + + if (!fence) + return -ENOMEM; + + fence_get(&fence->base); + sched_job->s_fence = fence; + + wait_event(entity->scheduler->job_scheduled, + amd_sched_entity_in(sched_job)); + + return 0; +} + +/** + * Return ture if we can push more jobs to the hw. + */ +static bool amd_sched_ready(struct amd_gpu_scheduler *sched) +{ + return atomic_read(&sched->hw_rq_count) < + sched->hw_submission_limit; +} + +/** + * Wake up the scheduler when it is ready + */ +static void amd_sched_wakeup(struct amd_gpu_scheduler *sched) +{ + if (amd_sched_ready(sched)) + wake_up_interruptible(&sched->wake_up_worker); +} + +/** + * Select next to run +*/ +static struct amd_sched_job * +amd_sched_select_job(struct amd_gpu_scheduler *sched) +{ + struct amd_sched_job *job; + + if (!amd_sched_ready(sched)) + return NULL; + + /* Kernel run queue has higher priority than normal run queue*/ + job = amd_sched_rq_select_job(&sched->kernel_rq); + if (job == NULL) + job = amd_sched_rq_select_job(&sched->sched_rq); + + return job; +} + +static void amd_sched_process_job(struct fence *f, struct fence_cb *cb) +{ + struct amd_sched_job *sched_job = + container_of(cb, struct amd_sched_job, cb); + struct amd_gpu_scheduler *sched; + + sched = sched_job->sched; + amd_sched_fence_signal(sched_job->s_fence); + atomic_dec(&sched->hw_rq_count); + fence_put(&sched_job->s_fence->base); + sched->ops->process_job(sched_job); + wake_up_interruptible(&sched->wake_up_worker); +} + +static int amd_sched_main(void *param) +{ + struct sched_param sparam = {.sched_priority = 1}; + struct amd_gpu_scheduler *sched = (struct amd_gpu_scheduler *)param; + int r; + + sched_setscheduler(current, SCHED_FIFO, &sparam); + + while (!kthread_should_stop()) { + struct amd_sched_entity *entity; + struct amd_sched_job *job; + struct fence *fence; + + wait_event_interruptible(sched->wake_up_worker, + kthread_should_stop() || + (job = amd_sched_select_job(sched))); + + if (!job) + continue; + + entity = job->s_entity; + atomic_inc(&sched->hw_rq_count); + fence = sched->ops->run_job(job); + if (fence) { + r = fence_add_callback(fence, &job->cb, + amd_sched_process_job); + if (r == -ENOENT) + amd_sched_process_job(fence, &job->cb); + else if (r) + DRM_ERROR("fence add callback failed (%d)\n", r); + fence_put(fence); + } + + kfifo_out(&entity->job_queue, &job, sizeof(job)); + wake_up(&sched->job_scheduled); + } + return 0; +} + +/** + * Create a gpu scheduler + * + * @ops The backend operations for this scheduler. + * @ring The the ring id for the scheduler. + * @hw_submissions Number of hw submissions to do. + * + * Return the pointer to scheduler for success, otherwise return NULL +*/ +struct amd_gpu_scheduler *amd_sched_create(struct amd_sched_backend_ops *ops, + unsigned ring, unsigned hw_submission, + void *priv) +{ + struct amd_gpu_scheduler *sched; + + sched = kzalloc(sizeof(struct amd_gpu_scheduler), GFP_KERNEL); + if (!sched) + return NULL; + + sched->ops = ops; + sched->ring_id = ring; + sched->hw_submission_limit = hw_submission; + sched->priv = priv; + snprintf(sched->name, sizeof(sched->name), "amdgpu[%d]", ring); + amd_sched_rq_init(&sched->sched_rq); + amd_sched_rq_init(&sched->kernel_rq); + + init_waitqueue_head(&sched->wake_up_worker); + init_waitqueue_head(&sched->job_scheduled); + atomic_set(&sched->hw_rq_count, 0); + /* Each scheduler will run on a seperate kernel thread */ + sched->thread = kthread_run(amd_sched_main, sched, sched->name); + if (IS_ERR(sched->thread)) { + DRM_ERROR("Failed to create scheduler for id %d.\n", ring); + kfree(sched); + return NULL; + } + + return sched; +} + +/** + * Destroy a gpu scheduler + * + * @sched The pointer to the scheduler + * + * return 0 if succeed. -1 if failed. + */ +int amd_sched_destroy(struct amd_gpu_scheduler *sched) +{ + kthread_stop(sched->thread); + kfree(sched); + return 0; +} |