Fix API for updating MVKDeviceConfiguration::synchronousQueueSubmits.

Notify MVKQueues when MVKDeviceConfiguration::synchronousQueueSubmits changes.
MVKQueue use or not use separate dispatch queue as a result.

MoltenVK/MoltenVK/GPUObjects/MVKDevice.h

@@ -266,6 +266,12 @@ public:
 	/** Block the current thread until all queues in this device are idle. */
 	VkResult waitIdle();
 
+	/** Returns a pointer to the MoltenVK configuration info for this device. */
+	const MVKDeviceConfiguration* getMoltenVKConfiguration();
+
+	/** Sets the MoltenVK configuration info for this device. */
+	void setMoltenVKConfiguration(const MVKDeviceConfiguration* pConfiguration);
+
 
 #pragma mark Object lifecycle
 

MoltenVK/MoltenVK/GPUObjects/MVKDevice.mm

@@ -1022,6 +1022,21 @@ VkResult MVKDevice::waitIdle() {
 	return VK_SUCCESS;
 }
 
+const MVKDeviceConfiguration* MVKDevice::getMoltenVKConfiguration() { return &_mvkConfig; }
+
+void MVKDevice::setMoltenVKConfiguration(const MVKDeviceConfiguration* pConfiguration) {
+	if ( !pConfiguration) { return; }
+
+	*(MVKDeviceConfiguration*)&_mvkConfig = *pConfiguration;
+
+	// Reconfigure the queues from the updated info
+	for (auto& queues : _queuesByQueueFamilyIndex) {
+		for (MVKQueue* q : queues) {
+			q->updateDeviceConfiguration();
+		}
+	}
+}
+
 
 #pragma mark Object lifecycle
 

MoltenVK/MoltenVK/GPUObjects/MVKQueue.h

@@ -127,6 +127,13 @@ public:
 	/** Constructs an instance for the device and queue family. */
 	MVKQueue(MVKDevice* device, MVKQueueFamily* queueFamily, uint32_t index, float priority);
 
+	/**
+	 * Called from MVKDevice when MVKDeviceConfiguration is updated.
+	 *
+	 * Updates the use of a dispatch queue based on the value of MVKDeviceConfiguration::synchronousQueueSubmits.
+	 */
+	void updateDeviceConfiguration();
+
 	~MVKQueue() override;
 
     /**
@@ -149,7 +156,6 @@ protected:
 	friend class MVKQueuePresentSurfaceSubmission;
 
 	void initName();
-	void initExecQueue();
 	void initMTLCommandQueue();
 	void initGPUCaptureScopes();
 	void destroyExecQueue();

MoltenVK/MoltenVK/GPUObjects/MVKQueue.mm

@@ -193,11 +193,13 @@ MVKQueue::MVKQueue(MVKDevice* device, MVKQueueFamily* queueFamily, uint32_t inde
 	_priority = priority;
 	_activeMTLCommandBufferCount = 0;
 	_nextMTLCmdBuffID = 1;
+	_execQueue = nullptr;	// Before updateDeviceConfiguration()
 
 	initName();
-	initExecQueue();
 	initMTLCommandQueue();
 	initGPUCaptureScopes();
+
+	updateDeviceConfiguration();
 }
 
 void MVKQueue::initName() {
@@ -207,12 +209,14 @@ void MVKQueue::initName() {
 	_name = name;
 }
 
-// Unless synchronous submission processing was configured,
+// If synchronous submission processing is not configured in the device,
 // creates and initializes the prioritized execution dispatch queue.
-void MVKQueue::initExecQueue() {
+// If synchronous submission processing is configured in the device,
+// destroys the internal execution dispatch queue if it exists.
+void MVKQueue::updateDeviceConfiguration() {
 	if (_device->_mvkConfig.synchronousQueueSubmits) {
-		_execQueue = nullptr;
-	} else {
+		destroyExecQueue();
+	} else if ( !_execQueue ) {
 		// Determine the dispatch queue priority
 		dispatch_qos_class_t dqQOS = MVK_DISPATCH_QUEUE_QOS_CLASS;
 		int dqPriority = (1.0 - _priority) * QOS_MIN_RELATIVE_PRIORITY;
@@ -255,7 +259,10 @@ MVKQueue::~MVKQueue() {
 
 // Destroys the execution dispatch queue.
 void MVKQueue::destroyExecQueue() {
-	if (_execQueue) { dispatch_release(_execQueue); }
+	if (_execQueue) {
+		dispatch_release(_execQueue);
+		_execQueue = nullptr;
+	}
 }
 
 

MoltenVK/MoltenVK/Vulkan/vk_mvk_moltenvk.mm

@@ -31,7 +31,7 @@ MVK_PUBLIC_SYMBOL void vkGetMoltenVKDeviceConfigurationMVK(
     MVKDeviceConfiguration*                     pConfiguration) {
 
     MVKDevice* mvkDev = MVKDevice::getMVKDevice(device);
-    if (pConfiguration) { *pConfiguration = mvkDev->_mvkConfig; }
+    if (pConfiguration) { *pConfiguration = *mvkDev->getMoltenVKConfiguration(); }
 }
 
 MVK_PUBLIC_SYMBOL VkResult vkSetMoltenVKDeviceConfigurationMVK(
@@ -39,7 +39,7 @@ MVK_PUBLIC_SYMBOL VkResult vkSetMoltenVKDeviceConfigurationMVK(
     MVKDeviceConfiguration*                     pConfiguration) {
 
     MVKDevice* mvkDev = MVKDevice::getMVKDevice(device);
-    if (pConfiguration) { *(MVKDeviceConfiguration*)&mvkDev->_mvkConfig = *pConfiguration; }
+    if (pConfiguration) { mvkDev->setMoltenVKConfiguration(pConfiguration); }
     return VK_SUCCESS;
 }