linux/drivers/gpu/drm/scheduler/sched_fence.c

183 lines
5.1 KiB
C

/*
* 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/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <drm/gpu_scheduler.h>
static struct kmem_cache *sched_fence_slab;
static int __init drm_sched_fence_slab_init(void)
{
sched_fence_slab = kmem_cache_create(
"drm_sched_fence", sizeof(struct drm_sched_fence), 0,
SLAB_HWCACHE_ALIGN, NULL);
if (!sched_fence_slab)
return -ENOMEM;
return 0;
}
static void __exit drm_sched_fence_slab_fini(void)
{
rcu_barrier();
kmem_cache_destroy(sched_fence_slab);
}
void drm_sched_fence_scheduled(struct drm_sched_fence *fence)
{
int ret = dma_fence_signal(&fence->scheduled);
if (!ret)
DMA_FENCE_TRACE(&fence->scheduled,
"signaled from irq context\n");
else
DMA_FENCE_TRACE(&fence->scheduled,
"was already signaled\n");
}
void drm_sched_fence_finished(struct drm_sched_fence *fence)
{
int ret = dma_fence_signal(&fence->finished);
if (!ret)
DMA_FENCE_TRACE(&fence->finished,
"signaled from irq context\n");
else
DMA_FENCE_TRACE(&fence->finished,
"was already signaled\n");
}
static const char *drm_sched_fence_get_driver_name(struct dma_fence *fence)
{
return "drm_sched";
}
static const char *drm_sched_fence_get_timeline_name(struct dma_fence *f)
{
struct drm_sched_fence *fence = to_drm_sched_fence(f);
return (const char *)fence->sched->name;
}
/**
* drm_sched_fence_free - free up the fence memory
*
* @rcu: RCU callback head
*
* Free up the fence memory after the RCU grace period.
*/
static void drm_sched_fence_free(struct rcu_head *rcu)
{
struct dma_fence *f = container_of(rcu, struct dma_fence, rcu);
struct drm_sched_fence *fence = to_drm_sched_fence(f);
kmem_cache_free(sched_fence_slab, fence);
}
/**
* drm_sched_fence_release_scheduled - callback that fence can be freed
*
* @fence: fence
*
* This function is called when the reference count becomes zero.
* It just RCU schedules freeing up the fence.
*/
static void drm_sched_fence_release_scheduled(struct dma_fence *f)
{
struct drm_sched_fence *fence = to_drm_sched_fence(f);
dma_fence_put(fence->parent);
call_rcu(&fence->finished.rcu, drm_sched_fence_free);
}
/**
* drm_sched_fence_release_finished - drop extra reference
*
* @f: fence
*
* Drop the extra reference from the scheduled fence to the base fence.
*/
static void drm_sched_fence_release_finished(struct dma_fence *f)
{
struct drm_sched_fence *fence = to_drm_sched_fence(f);
dma_fence_put(&fence->scheduled);
}
static const struct dma_fence_ops drm_sched_fence_ops_scheduled = {
.get_driver_name = drm_sched_fence_get_driver_name,
.get_timeline_name = drm_sched_fence_get_timeline_name,
.release = drm_sched_fence_release_scheduled,
};
static const struct dma_fence_ops drm_sched_fence_ops_finished = {
.get_driver_name = drm_sched_fence_get_driver_name,
.get_timeline_name = drm_sched_fence_get_timeline_name,
.release = drm_sched_fence_release_finished,
};
struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f)
{
if (f->ops == &drm_sched_fence_ops_scheduled)
return container_of(f, struct drm_sched_fence, scheduled);
if (f->ops == &drm_sched_fence_ops_finished)
return container_of(f, struct drm_sched_fence, finished);
return NULL;
}
EXPORT_SYMBOL(to_drm_sched_fence);
struct drm_sched_fence *drm_sched_fence_create(struct drm_sched_entity *entity,
void *owner)
{
struct drm_sched_fence *fence = NULL;
unsigned seq;
fence = kmem_cache_zalloc(sched_fence_slab, GFP_KERNEL);
if (fence == NULL)
return NULL;
fence->owner = owner;
fence->sched = entity->rq->sched;
spin_lock_init(&fence->lock);
seq = atomic_inc_return(&entity->fence_seq);
dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled,
&fence->lock, entity->fence_context, seq);
dma_fence_init(&fence->finished, &drm_sched_fence_ops_finished,
&fence->lock, entity->fence_context + 1, seq);
return fence;
}
module_init(drm_sched_fence_slab_init);
module_exit(drm_sched_fence_slab_fini);
MODULE_DESCRIPTION("DRM GPU scheduler");
MODULE_LICENSE("GPL and additional rights");