[dxvk] Explicitly stop state cache worker threads on device destruction

Otherwise, the workers may access objects that are being destroyed an
app thread.

src/dxvk/dxvk_device.cpp

@@ -29,6 +29,10 @@ namespace dxvk {
     // Wait for all pending Vulkan commands to be
     // executed before we destroy any resources.
     this->waitForIdle();
+
+    // Stop workers explicitly in order to prevent
+    // access to structures that are being destroyed.
+    m_objects.pipelineManager().stopWorkerThreads();
   }
 
 

src/dxvk/dxvk_pipemanager.cpp

@@ -79,4 +79,10 @@ namespace dxvk {
         && m_stateCache->isCompilingShaders();
   }
 
+
+  void DxvkPipelineManager::stopWorkerThreads() const {
+    if (m_stateCache != nullptr)
+      m_stateCache->stopWorkerThreads();
+  }
+  
 }

src/dxvk/dxvk_pipemanager.h

@@ -90,6 +90,11 @@ namespace dxvk {
      */
     bool isCompilingShaders() const;
 
+    /**
+     * \brief Stops async compiler threads
+     */
+    void stopWorkerThreads() const;
+    
   private:
     
     const DxvkDevice*         m_device;

src/dxvk/dxvk_state_cache.cpp

@@ -210,19 +210,7 @@ namespace dxvk {
   
 
   DxvkStateCache::~DxvkStateCache() {
-    { std::lock_guard<dxvk::mutex> workerLock(m_workerLock);
+    this->stopWorkerThreads();
-      std::lock_guard<dxvk::mutex> writerLock(m_writerLock);
-
-      m_stopThreads.store(true);
-
-      m_workerCond.notify_all();
-      m_writerCond.notify_all();
-    }
-
-    for (auto& worker : m_workerThreads)
-      worker.join();
-    
-    m_writerThread.join();
   }
 
 
@@ -314,6 +302,24 @@ namespace dxvk {
   }
 
 
+  void DxvkStateCache::stopWorkerThreads() {
+    { std::lock_guard<dxvk::mutex> workerLock(m_workerLock);
+      std::lock_guard<dxvk::mutex> writerLock(m_writerLock);
+
+      if (m_stopThreads.exchange(true))
+        return;
+
+      m_workerCond.notify_all();
+      m_writerCond.notify_all();
+    }
+
+    for (auto& worker : m_workerThreads)
+      worker.join();
+    
+    m_writerThread.join();
+  }
+
+
   DxvkShaderKey DxvkStateCache::getShaderKey(const Rc<DxvkShader>& shader) const {
     return shader != nullptr ? shader->getShaderKey() : g_nullShaderKey;
   }

src/dxvk/dxvk_state_cache.h

@@ -71,6 +71,11 @@ namespace dxvk {
     void registerShader(
       const Rc<DxvkShader>&                 shader);
 
+    /**
+     * \brief Explicitly stops worker threads
+     */
+    void stopWorkerThreads();
+
     /**
      * \brief Checks whether compiler threads are busy
      * \returns \c true if we're compiling shaders