diff options
Diffstat (limited to 'drivers/gpu/drm/amd/scheduler/gpu_scheduler.c')
| -rw-r--r-- | drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 462 |
1 files changed, 462 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..265d3e2f63cc --- /dev/null +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c @@ -0,0 +1,462 @@ +/* + * 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" + +/* Initialize a given run queue struct */ +static void amd_sched_rq_init(struct amd_sched_rq *rq) +{ + INIT_LIST_HEAD(&rq->entities); + mutex_init(&rq->lock); + rq->current_entity = NULL; +} + +static void amd_sched_rq_add_entity(struct amd_sched_rq *rq, + struct amd_sched_entity *entity) +{ + mutex_lock(&rq->lock); + list_add_tail(&entity->list, &rq->entities); + mutex_unlock(&rq->lock); +} + +static void amd_sched_rq_remove_entity(struct amd_sched_rq *rq, + struct amd_sched_entity *entity) +{ + mutex_lock(&rq->lock); + list_del_init(&entity->list); + if (rq->current_entity == entity) + rq->current_entity = NULL; + mutex_unlock(&rq->lock); +} + +/** + * Select next entity from a specified run queue with round robin policy. + * It could return the same entity as current one if current is the only + * available one in the queue. Return NULL if nothing available. + */ +static struct amd_sched_entity * +amd_sched_rq_select_entity(struct amd_sched_rq *rq) +{ + struct amd_sched_entity *entity = rq->current_entity; + + if (entity) { + list_for_each_entry_continue(entity, &rq->entities, list) { + if (!kfifo_is_empty(&entity->job_queue)) { + rq->current_entity = entity; + return rq->current_entity; + } + } + } + + list_for_each_entry(entity, &rq->entities, list) { + + if (!kfifo_is_empty(&entity->job_queue)) { + rq->current_entity = entity; + return rq->current_entity; + } + + if (entity == rq->current_entity) + break; + } + + return NULL; +} + +/** + * Note: This function should only been called inside scheduler main + * function for thread safety, there is no other protection here. + * return ture if scheduler has something ready to run. + * + * For active_hw_rq, there is only one producer(scheduler thread) and + * one consumer(ISR). It should be safe to use this function in scheduler + * main thread to decide whether to continue emit more IBs. +*/ +static bool is_scheduler_ready(struct amd_gpu_scheduler *sched) +{ + unsigned long flags; + bool full; + + spin_lock_irqsave(&sched->queue_lock, flags); + full = atomic64_read(&sched->hw_rq_count) < + sched->hw_submission_limit ? true : false; + spin_unlock_irqrestore(&sched->queue_lock, flags); + + return full; +} + +/** + * Select next entity from the kernel run queue, if not available, + * return null. +*/ +static struct amd_sched_entity * +kernel_rq_select_context(struct amd_gpu_scheduler *sched) +{ + struct amd_sched_entity *sched_entity; + struct amd_sched_rq *rq = &sched->kernel_rq; + + mutex_lock(&rq->lock); + sched_entity = amd_sched_rq_select_entity(rq); + mutex_unlock(&rq->lock); + return sched_entity; +} + +/** + * Select next entity containing real IB submissions +*/ +static struct amd_sched_entity * +select_context(struct amd_gpu_scheduler *sched) +{ + struct amd_sched_entity *wake_entity = NULL; + struct amd_sched_entity *tmp; + struct amd_sched_rq *rq; + + if (!is_scheduler_ready(sched)) + return NULL; + + /* Kernel run queue has higher priority than normal run queue*/ + tmp = kernel_rq_select_context(sched); + if (tmp != NULL) + goto exit; + + rq = &sched->sched_rq; + mutex_lock(&rq->lock); + tmp = amd_sched_rq_select_entity(rq); + mutex_unlock(&rq->lock); +exit: + if (sched->current_entity && (sched->current_entity != tmp)) + wake_entity = sched->current_entity; + sched->current_entity = tmp; + if (wake_entity && wake_entity->need_wakeup) + wake_up(&wake_entity->wait_queue); + return tmp; +} + +/** + * 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) +{ + uint64_t seq_ring = 0; + char name[20]; + + if (!(sched && entity && rq)) + return -EINVAL; + + memset(entity, 0, sizeof(struct amd_sched_entity)); + seq_ring = ((uint64_t)sched->ring_id) << 60; + spin_lock_init(&entity->lock); + entity->belongto_rq = rq; + entity->scheduler = sched; + init_waitqueue_head(&entity->wait_queue); + init_waitqueue_head(&entity->wait_emit); + entity->fence_context = fence_context_alloc(1); + snprintf(name, sizeof(name), "c_entity[%llu]", entity->fence_context); + memcpy(entity->name, name, 20); + entity->need_wakeup = false; + if(kfifo_alloc(&entity->job_queue, + jobs * sizeof(void *), + GFP_KERNEL)) + return -EINVAL; + + spin_lock_init(&entity->queue_lock); + atomic64_set(&entity->last_queued_v_seq, seq_ring); + atomic64_set(&entity->last_signaled_v_seq, seq_ring); + + /* 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 is_context_entity_initialized(struct amd_gpu_scheduler *sched, + struct amd_sched_entity *entity) +{ + return entity->scheduler == sched && + entity->belongto_rq != NULL; +} + +static bool is_context_entity_idle(struct amd_gpu_scheduler *sched, + struct amd_sched_entity *entity) +{ + /** + * Idle means no pending IBs, and the entity is not + * currently being used. + */ + barrier(); + if ((sched->current_entity != entity) && + 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 + * + * return 0 if succeed. negative error code on failure + */ +int amd_sched_entity_fini(struct amd_gpu_scheduler *sched, + struct amd_sched_entity *entity) +{ + int r = 0; + struct amd_sched_rq *rq = entity->belongto_rq; + + if (!is_context_entity_initialized(sched, entity)) + return 0; + entity->need_wakeup = true; + /** + * The client will not queue more IBs during this fini, consume existing + * queued IBs + */ + r = wait_event_timeout( + entity->wait_queue, + is_context_entity_idle(sched, entity), + msecs_to_jiffies(AMD_GPU_WAIT_IDLE_TIMEOUT_IN_MS) + ) ? 0 : -1; + + if (r) { + if (entity->is_pending) + DRM_INFO("Entity %p is in waiting state during fini,\ + all pending ibs will be canceled.\n", + entity); + } + + amd_sched_rq_remove_entity(rq, entity); + kfifo_free(&entity->job_queue); + return r; +} + +/** + * Submit a normal job to the job queue + * + * @sched The pointer to the scheduler + * @c_entity The pointer to amd_sched_entity + * @job The pointer to job required to submit + * return 0 if succeed. -1 if failed. + * -2 indicate queue is full for this client, client should wait untill + * scheduler consum some queued command. + * -1 other fail. +*/ +int amd_sched_push_job(struct amd_gpu_scheduler *sched, + struct amd_sched_entity *c_entity, + void *data, + struct amd_sched_fence **fence) +{ + struct amd_sched_job *job; + + if (!fence) + return -EINVAL; + job = kzalloc(sizeof(struct amd_sched_job), GFP_KERNEL); + if (!job) + return -ENOMEM; + job->sched = sched; + job->s_entity = c_entity; + job->data = data; + *fence = amd_sched_fence_create(c_entity); + if ((*fence) == NULL) { + kfree(job); + return -EINVAL; + } + fence_get(&(*fence)->base); + job->s_fence = *fence; + while (kfifo_in_spinlocked(&c_entity->job_queue, &job, sizeof(void *), + &c_entity->queue_lock) != sizeof(void *)) { + /** + * Current context used up all its IB slots + * wait here, or need to check whether GPU is hung + */ + schedule(); + } + /* first job wake up scheduler */ + if ((kfifo_len(&c_entity->job_queue) / sizeof(void *)) == 1) + wake_up_interruptible(&sched->wait_queue); + return 0; +} + +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; + unsigned long flags; + + sched = sched_job->sched; + atomic64_set(&sched_job->s_entity->last_signaled_v_seq, + sched_job->s_fence->v_seq); + amd_sched_fence_signal(sched_job->s_fence); + spin_lock_irqsave(&sched->queue_lock, flags); + list_del(&sched_job->list); + atomic64_dec(&sched->hw_rq_count); + spin_unlock_irqrestore(&sched->queue_lock, flags); + + sched->ops->process_job(sched, sched_job); + fence_put(&sched_job->s_fence->base); + kfree(sched_job); + wake_up_interruptible(&sched->wait_queue); +} + +static int amd_sched_main(void *param) +{ + int r; + struct amd_sched_job *job; + struct sched_param sparam = {.sched_priority = 1}; + struct amd_sched_entity *c_entity = NULL; + struct amd_gpu_scheduler *sched = (struct amd_gpu_scheduler *)param; + + sched_setscheduler(current, SCHED_FIFO, &sparam); + + while (!kthread_should_stop()) { + struct fence *fence; + + wait_event_interruptible(sched->wait_queue, + is_scheduler_ready(sched) && + (c_entity = select_context(sched))); + r = kfifo_out(&c_entity->job_queue, &job, sizeof(void *)); + if (r != sizeof(void *)) + continue; + r = sched->ops->prepare_job(sched, c_entity, job); + if (!r) { + unsigned long flags; + spin_lock_irqsave(&sched->queue_lock, flags); + list_add_tail(&job->list, &sched->active_hw_rq); + atomic64_inc(&sched->hw_rq_count); + spin_unlock_irqrestore(&sched->queue_lock, flags); + } + mutex_lock(&sched->sched_lock); + fence = sched->ops->run_job(sched, c_entity, 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); + } + mutex_unlock(&sched->sched_lock); + } + return 0; +} + +/** + * Create a gpu scheduler + * + * @device The device context for this scheduler + * @ops The backend operations for this scheduler. + * @id The scheduler is per ring, here is ring id. + * @granularity The minumum ms unit the scheduler will scheduled. + * @preemption Indicate whether this ring support preemption, 0 is no. + * + * return the pointer to scheduler for success, otherwise return NULL +*/ +struct amd_gpu_scheduler *amd_sched_create(void *device, + struct amd_sched_backend_ops *ops, + unsigned ring, + unsigned granularity, + unsigned preemption, + unsigned hw_submission) +{ + struct amd_gpu_scheduler *sched; + char name[20]; + + sched = kzalloc(sizeof(struct amd_gpu_scheduler), GFP_KERNEL); + if (!sched) + return NULL; + + sched->device = device; + sched->ops = ops; + sched->granularity = granularity; + sched->ring_id = ring; + sched->preemption = preemption; + sched->hw_submission_limit = hw_submission; + snprintf(name, sizeof(name), "gpu_sched[%d]", ring); + mutex_init(&sched->sched_lock); + spin_lock_init(&sched->queue_lock); + amd_sched_rq_init(&sched->sched_rq); + amd_sched_rq_init(&sched->kernel_rq); + + init_waitqueue_head(&sched->wait_queue); + INIT_LIST_HEAD(&sched->active_hw_rq); + atomic64_set(&sched->hw_rq_count, 0); + /* Each scheduler will run on a seperate kernel thread */ + sched->thread = kthread_create(amd_sched_main, sched, name); + if (sched->thread) { + wake_up_process(sched->thread); + return sched; + } + + DRM_ERROR("Failed to create scheduler for id %d.\n", ring); + kfree(sched); + return NULL; +} + +/** + * 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; +} + +/** + * Get next queued sequence number + * + * @entity The context entity + * + * return the next queued sequence number +*/ +uint64_t amd_sched_next_queued_seq(struct amd_sched_entity *c_entity) +{ + return atomic64_read(&c_entity->last_queued_v_seq) + 1; +} |