yuzu/src/video_core/renderer_vulkan/vk_fence_manager.cpp
ReinUsesLisp 58b0ae84b5 renderer_vulkan: Make unconditional use of VK_KHR_timeline_semaphore
This reworks how host<->device synchronization works on the Vulkan
backend. Instead of "protecting" resources with a fence and signalling
these as free when the fence is known to be signalled by the host GPU,
use timeline semaphores.

Vulkan timeline semaphores allow use to work on a subset of D3D12
fences. As far as we are concerned, timeline semaphores are a value set
by the host or the device that can be waited by either of them.

Taking advantange of this, we can have a monolithically increasing
atomic value for each submission to the graphics queue. Instead of
protecting resources with a fence, we simply store the current logical
tick (the atomic value stored in CPU memory). When we want to know if a
resource is free, it can be compared to the current GPU tick.

This greatly simplifies resource management code and the free status of
resources should have less false negatives.

To workaround bugs in validation layers, when these are attached there's
a thread waiting for timeline semaphores.
2020-09-19 01:46:37 -03:00

101 lines
3 KiB
C++

// Copyright 2020 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <memory>
#include <thread>
#include "video_core/renderer_vulkan/vk_buffer_cache.h"
#include "video_core/renderer_vulkan/vk_device.h"
#include "video_core/renderer_vulkan/vk_fence_manager.h"
#include "video_core/renderer_vulkan/vk_scheduler.h"
#include "video_core/renderer_vulkan/vk_texture_cache.h"
#include "video_core/renderer_vulkan/wrapper.h"
namespace Vulkan {
InnerFence::InnerFence(const VKDevice& device, VKScheduler& scheduler, u32 payload, bool is_stubbed)
: VideoCommon::FenceBase(payload, is_stubbed), device{device}, scheduler{scheduler} {}
InnerFence::InnerFence(const VKDevice& device, VKScheduler& scheduler, GPUVAddr address,
u32 payload, bool is_stubbed)
: VideoCommon::FenceBase(address, payload, is_stubbed), device{device}, scheduler{scheduler} {}
InnerFence::~InnerFence() = default;
void InnerFence::Queue() {
if (is_stubbed) {
return;
}
ASSERT(!event);
event = device.GetLogical().CreateEvent();
ticks = scheduler.CurrentTick();
scheduler.RequestOutsideRenderPassOperationContext();
scheduler.Record([event = *event](vk::CommandBuffer cmdbuf) {
cmdbuf.SetEvent(event, VK_PIPELINE_STAGE_ALL_COMMANDS_BIT);
});
}
bool InnerFence::IsSignaled() const {
if (is_stubbed) {
return true;
}
ASSERT(event);
return IsEventSignalled();
}
void InnerFence::Wait() {
if (is_stubbed) {
return;
}
ASSERT(event);
if (ticks >= scheduler.CurrentTick()) {
scheduler.Flush();
}
while (!IsEventSignalled()) {
std::this_thread::yield();
}
}
bool InnerFence::IsEventSignalled() const {
switch (const VkResult result = event.GetStatus()) {
case VK_EVENT_SET:
return true;
case VK_EVENT_RESET:
return false;
default:
throw vk::Exception(result);
}
}
VKFenceManager::VKFenceManager(VideoCore::RasterizerInterface& rasterizer, Tegra::GPU& gpu,
Tegra::MemoryManager& memory_manager, VKTextureCache& texture_cache,
VKBufferCache& buffer_cache, VKQueryCache& query_cache,
const VKDevice& device_, VKScheduler& scheduler_)
: GenericFenceManager(rasterizer, gpu, texture_cache, buffer_cache, query_cache),
device{device_}, scheduler{scheduler_} {}
Fence VKFenceManager::CreateFence(u32 value, bool is_stubbed) {
return std::make_shared<InnerFence>(device, scheduler, value, is_stubbed);
}
Fence VKFenceManager::CreateFence(GPUVAddr addr, u32 value, bool is_stubbed) {
return std::make_shared<InnerFence>(device, scheduler, addr, value, is_stubbed);
}
void VKFenceManager::QueueFence(Fence& fence) {
fence->Queue();
}
bool VKFenceManager::IsFenceSignaled(Fence& fence) const {
return fence->IsSignaled();
}
void VKFenceManager::WaitFence(Fence& fence) {
fence->Wait();
}
} // namespace Vulkan