[dxvk] Refactor events to be properly ref-counted

Mostly serves as a proof-of-concept for the pending query rework,
but also cleans up some silly code.

src/dxvk/dxvk_cmdlist.cpp

@@ -370,7 +370,6 @@ namespace dxvk {
 
     // Return query and event handles
     m_gpuQueryTracker.reset();
-    m_gpuEventTracker.reset();
 
     // Less important stuff
     m_signalTracker.reset();

src/dxvk/dxvk_cmdlist.h

@@ -284,17 +284,10 @@ namespace dxvk {
       m_resources.trackSampler(sampler);
     }
 
-    /**
-     * \brief Tracks a GPU event
-     * 
-     * The event will be returned to its event pool
-     * after the command buffer has finished executing.
-     * \param [in] handle Event handle
-     */
-    void trackGpuEvent(DxvkGpuEventHandle handle) {
-      m_gpuEventTracker.trackEvent(handle);
+    void trackEvent(Rc<DxvkGpuEvent>&& event) {
+      m_resources.trackEvent(std::move(event));
     }
-    
+
     /**
      * \brief Tracks a GPU query
      * 
@@ -1082,7 +1075,6 @@ namespace dxvk {
 
     DxvkLifetimeTracker       m_resources;
     DxvkSignalTracker         m_signalTracker;
-    DxvkGpuEventTracker       m_gpuEventTracker;
     DxvkGpuQueryTracker       m_gpuQueryTracker;
     DxvkStatCounters          m_statCounters;
 

src/dxvk/dxvk_context.cpp

@@ -2470,22 +2470,21 @@ namespace dxvk {
   void DxvkContext::signalGpuEvent(const Rc<DxvkEvent>& event) {
     this->spillRenderPass(true);
     
-    DxvkGpuEventHandle handle = m_common->eventPool().allocEvent();
+    Rc<DxvkGpuEvent> gpuEvent = m_common->eventPool().allocEvent();
+    event->assignGpuEvent(gpuEvent);
 
     // Supported client APIs can't access device memory in a defined manner
     // without triggering a queue submission first, so we really only need
     // to wait for prior commands, especially queries, to complete.
     VkMemoryBarrier2 barrier = { VK_STRUCTURE_TYPE_MEMORY_BARRIER_2 };
-    barrier.srcStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
+    barrier.srcStageMask = VK_PIPELINE_STAGE_2_ALL_COMMANDS_BIT;
 
     VkDependencyInfo depInfo = { VK_STRUCTURE_TYPE_DEPENDENCY_INFO };
     depInfo.memoryBarrierCount = 1;
     depInfo.pMemoryBarriers = &barrier;
 
-    m_cmd->cmdSetEvent(handle.event, &depInfo);
-
-    m_cmd->trackGpuEvent(event->reset(handle));
-    m_cmd->trackResource<DxvkAccess::None>(event);
+    m_cmd->cmdSetEvent(gpuEvent->handle(), &depInfo);
+    m_cmd->trackEvent(std::move(gpuEvent));
   }
   
 

src/dxvk/dxvk_device.cpp

@@ -139,7 +139,7 @@ namespace dxvk {
 
 
   Rc<DxvkEvent> DxvkDevice::createGpuEvent() {
-    return new DxvkEvent(m_vkd);
+    return new DxvkEvent(this);
   }
 
 

src/dxvk/dxvk_gpu_event.cpp

@@ -3,34 +3,76 @@
 
 namespace dxvk {
 
-  DxvkEvent::DxvkEvent(const Rc<vk::DeviceFn>& vkd)
-  : m_vkd(vkd) { }
+  DxvkGpuEvent::DxvkGpuEvent(
+          DxvkGpuEventPool*           parent)
+  : m_pool(parent) {
+    auto vk = m_pool->m_vkd;
 
+    VkEventCreateInfo info = { VK_STRUCTURE_TYPE_EVENT_CREATE_INFO };
+    VkResult vr = vk->vkCreateEvent(vk->device(), &info, nullptr, &m_event);
 
-  DxvkEvent::~DxvkEvent() {
-    if (m_handle.pool && m_handle.event)
-      m_handle.pool->freeEvent(m_handle.event);
+    if (vr != VK_SUCCESS)
+      throw DxvkError(str::format("Failed to create event: ", vr));
   }
 
 
-  DxvkGpuEventStatus DxvkEvent::test() const {
-    if (!m_handle.event)
+  DxvkGpuEvent::~DxvkGpuEvent() {
+    auto vk = m_pool->m_vkd;
+    vk->vkDestroyEvent(vk->device(), m_event, nullptr);
+  }
+
+
+  void DxvkGpuEvent::free() {
+    m_pool->freeEvent(this);
+  }
+
+
+
+  DxvkEvent::DxvkEvent(const Rc<DxvkDevice>& device)
+  : m_device(device) { }
+
+
+  DxvkEvent::~DxvkEvent() {
+
+  }
+
+
+  DxvkGpuEventStatus DxvkEvent::test() {
+    std::lock_guard lock(m_mutex);
+
+    if (m_status == VK_EVENT_SET)
+      return DxvkGpuEventStatus::Signaled;
+
+    if (!m_gpuEvent)
       return DxvkGpuEventStatus::Invalid;
-    
-    VkResult status = m_vkd->vkGetEventStatus(
-      m_vkd->device(), m_handle.event);
-    
-    switch (status) {
-      case VK_EVENT_SET:    return DxvkGpuEventStatus::Signaled;
-      case VK_EVENT_RESET:  return DxvkGpuEventStatus::Pending;
-      default:              return DxvkGpuEventStatus::Invalid;
+
+    // Query current event status and recycle
+    // it as soon as a signal is observed.
+    auto vk = m_device->vkd();
+
+    m_status = vk->vkGetEventStatus(
+      vk->device(), m_gpuEvent->handle());
+
+    switch (m_status) {
+      case VK_EVENT_SET:
+        m_gpuEvent = nullptr;
+        return DxvkGpuEventStatus::Signaled;
+
+      case VK_EVENT_RESET:
+        return DxvkGpuEventStatus::Pending;
+
+      default:
+        return DxvkGpuEventStatus::Invalid;
     }
   }
 
 
-  DxvkGpuEventHandle DxvkEvent::reset(DxvkGpuEventHandle handle) {
-    m_vkd->vkResetEvent(m_vkd->device(), handle.event);
-    return std::exchange(m_handle, handle);
+  void DxvkEvent::assignGpuEvent(
+          Rc<DxvkGpuEvent>             event) {
+    std::lock_guard lock(m_mutex);
+
+    m_gpuEvent = std::move(event);
+    m_status = VK_NOT_READY;
   }
 
 
@@ -41,61 +83,31 @@ namespace dxvk {
 
 
   DxvkGpuEventPool::~DxvkGpuEventPool() {
-    for (VkEvent ev : m_events)
-      m_vkd->vkDestroyEvent(m_vkd->device(), ev, nullptr);
+    for (auto e : m_freeEvents)
+      delete e;
   }
 
   
-  DxvkGpuEventHandle DxvkGpuEventPool::allocEvent() {
-    VkEvent event = VK_NULL_HANDLE;
+  Rc<DxvkGpuEvent> DxvkGpuEventPool::allocEvent() {
+    std::lock_guard lock(m_mutex);
 
-    { std::lock_guard<dxvk::mutex> lock(m_mutex);
-      
-      if (m_events.size() > 0) {
-        event = m_events.back();
-        m_events.pop_back();
-      }
+    Rc<DxvkGpuEvent> event;
+
+    if (m_freeEvents.empty()) {
+      event = new DxvkGpuEvent(this);
+    } else {
+      event = m_freeEvents.back();
+      m_freeEvents.pop_back();
     }
 
-    if (!event) {
-      VkEventCreateInfo info = { VK_STRUCTURE_TYPE_EVENT_CREATE_INFO };
-
-      VkResult status = m_vkd->vkCreateEvent(
-        m_vkd->device(), &info, nullptr, &event);
-      
-      if (status != VK_SUCCESS) {
-        Logger::err("DXVK: Failed to create GPU event");
-        return DxvkGpuEventHandle();
-      }
-    }
-
-    return { this, event };
+    m_vkd->vkResetEvent(m_vkd->device(), event->handle());
+    return event;
   }
 
 
-  void DxvkGpuEventPool::freeEvent(VkEvent event) {
-    std::lock_guard<dxvk::mutex> lock(m_mutex);
-    m_events.push_back(event);
-  }
-
-
-
-
-  DxvkGpuEventTracker::DxvkGpuEventTracker() { }
-  DxvkGpuEventTracker::~DxvkGpuEventTracker() { }
-
-
-  void DxvkGpuEventTracker::trackEvent(DxvkGpuEventHandle handle) {
-    if (handle.pool && handle.event)
-      m_handles.push_back(handle);
-  }
-
-
-  void DxvkGpuEventTracker::reset() {
-    for (const auto& h : m_handles)
-      h.pool->freeEvent(h.event);
-    
-    m_handles.clear();
+  void DxvkGpuEventPool::freeEvent(DxvkGpuEvent* event) {
+    std::lock_guard lock(m_mutex);
+    m_freeEvents.push_back(event);
   }
 
 }

src/dxvk/dxvk_gpu_event.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <atomic>
 #include <vector>
 
 #include "dxvk_resource.h"
@@ -29,9 +30,50 @@ namespace dxvk {
    * as a pointer to the pool that the event
    * was allocated from.
    */
-  struct DxvkGpuEventHandle {
-    DxvkGpuEventPool* pool  = nullptr;
-    VkEvent           event = VK_NULL_HANDLE;
+  class DxvkGpuEvent {
+
+  public:
+
+    explicit DxvkGpuEvent(
+            DxvkGpuEventPool*           parent);
+
+    ~DxvkGpuEvent();
+
+    /**
+     * \brief Increments ref count
+     */
+    void incRef() {
+      m_refs.fetch_add(1u, std::memory_order_acquire);
+    }
+
+    /**
+     * \brief Decrements ref count
+     *
+     * Returns event to the pool if no further
+     * references exist for this event.
+     */
+    void decRef() {
+      if (m_refs.fetch_sub(1u, std::memory_order_release) == 1u)
+        free();
+    }
+
+    /**
+     * \brief Queries event handle
+     * \returns Event handle
+     */
+    VkEvent handle() const {
+      return m_event;
+    }
+
+  private:
+
+    DxvkGpuEventPool*     m_pool  = nullptr;
+    VkEvent               m_event = VK_NULL_HANDLE;
+
+    std::atomic<uint32_t> m_refs  = { 0u };
+
+    void free();
+
   };
 
 
@@ -42,13 +84,29 @@ namespace dxvk {
    * the application to check whether a specific
    * command has completed execution.
    */
-  class DxvkEvent : public DxvkResource {
-
+  class DxvkEvent {
+    friend class DxvkContext;
   public:
 
-    DxvkEvent(const Rc<vk::DeviceFn>& vkd);
+    DxvkEvent(const Rc<DxvkDevice>& device);
     ~DxvkEvent();
 
+    /**
+     * \brief Increments reference count
+     */
+    force_inline void incRef() {
+      m_refCount.fetch_add(1u, std::memory_order_acquire);
+    }
+
+    /**
+     * \brief Decrements reference count
+     * Frees the event as necessary.
+     */
+    force_inline void decRef() {
+      if (m_refCount.fetch_sub(1u, std::memory_order_release) == 1u)
+        delete this;
+    }
+
     /**
      * \brief Retrieves event status
      * 
@@ -56,24 +114,20 @@ namespace dxvk {
      * recorded intro a command buffer.
      * \returns Event status
      */
-    DxvkGpuEventStatus test() const;
-
-    /**
-     * \brief Resets event
-     * 
-     * Assigns a new Vulkan event to this event
-     * object and replaces the old one. The old
-     * event should be freed as soon as the GPU
-     * stops using it.
-     * \param [in] handle New GPU event handle
-     * \returns Old GPU event handle
-     */
-    DxvkGpuEventHandle reset(DxvkGpuEventHandle handle);
+    DxvkGpuEventStatus test();
 
   private:
 
-    Rc<vk::DeviceFn>   m_vkd;
-    DxvkGpuEventHandle m_handle;
+    std::atomic<uint32_t> m_refCount = { 0u };
+
+    sync::Spinlock    m_mutex;
+    VkResult          m_status = VK_NOT_READY;
+
+    Rc<DxvkDevice>    m_device;
+    Rc<DxvkGpuEvent>  m_gpuEvent;
+
+    void assignGpuEvent(
+            Rc<DxvkGpuEvent>            event);
 
   };
 
@@ -85,7 +139,7 @@ namespace dxvk {
    * a way to create and recycle Vulkan events.
    */
   class DxvkGpuEventPool {
-  
+    friend class DxvkGpuEvent;
   public:
 
     DxvkGpuEventPool(const DxvkDevice* device);
@@ -99,56 +153,22 @@ namespace dxvk {
      * state of the event is undefined.
      * \returns An event handle
      */
-    DxvkGpuEventHandle allocEvent();
+    Rc<DxvkGpuEvent> allocEvent();
 
     /**
      * \brief Recycles an event
      * 
-     * \param [in] handle Event to free
+     * \param [in] event Event object to free
      */
-    void freeEvent(VkEvent event);
+    void freeEvent(DxvkGpuEvent* event);
 
   private:
 
-    Rc<vk::DeviceFn>     m_vkd;
-    dxvk::mutex          m_mutex;
-    std::vector<VkEvent> m_events;
+    Rc<vk::DeviceFn>            m_vkd;
+
+    dxvk::mutex                 m_mutex;
+    std::vector<DxvkGpuEvent*>  m_freeEvents;
 
   };
 
-
-  /**
-   * \brief GPU event tracker
-   * 
-   * Stores events currently accessed by the
-   * GPU, and returns them to the event pool
-   * once they are no longer in use.
-   */
-  class DxvkGpuEventTracker {
-
-  public:
-
-    DxvkGpuEventTracker();
-    ~DxvkGpuEventTracker();
-
-    /**
-     * \brief Tracks an event
-     * \param [in] handle Event to track
-     */
-    void trackEvent(DxvkGpuEventHandle handle);
-
-    /**
-     * \brief Resets event tracker
-     * 
-     * Releases all tracked events back
-     * to the respective event pool
-     */
-    void reset();
-
-  private:
-
-    std::vector<DxvkGpuEventHandle> m_handles;
-
-  };
-
-}
+}

src/dxvk/dxvk_lifetime.cpp

@@ -10,6 +10,7 @@ namespace dxvk {
     m_resources.clear();
     m_allocations.clear();
     m_samplers.clear();
+    m_events.clear();
   }
   
 }

src/dxvk/dxvk_lifetime.h

@@ -2,6 +2,7 @@
 
 #include <vector>
 
+#include "dxvk_gpu_event.h"
 #include "dxvk_resource.h"
 #include "dxvk_sampler.h"
 
@@ -115,6 +116,14 @@ namespace dxvk {
       m_samplers.push_back(res);
     }
 
+    /**
+     * \brief Adds an event to track
+     * \param [in] res The event to track
+     */
+    void trackEvent(Rc<DxvkGpuEvent>&& event) {
+      m_events.push_back(std::move(event));
+    }
+
     /**
      * \brief Adds a resource to track
      * \param [in] res The resource to track
@@ -142,6 +151,7 @@ namespace dxvk {
   private:
 
     std::vector<Rc<DxvkSampler>> m_samplers;
+    std::vector<Rc<DxvkGpuEvent>> m_events;
 
     std::vector<DxvkLifetime<DxvkResource>> m_resources;
     std::vector<DxvkLifetime<DxvkResourceAllocation>> m_allocations;