layers: threading - use std mutex

Change-Id: I773ea148807e5b634ad021ea58b001cd3d1bad87
diff --git a/layers/threading.cpp b/layers/threading.cpp
index 5138184..d23c9ff 100644
--- a/layers/threading.cpp
+++ b/layers/threading.cpp
@@ -48,12 +48,6 @@
 static void initThreading(layer_data *my_data, const VkAllocationCallbacks *pAllocator) {
 
     layer_debug_actions(my_data->report_data, my_data->logging_callback, pAllocator, "google_threading");
-
-    if (!threadingLockInitialized) {
-        loader_platform_thread_create_mutex(&threadingLock);
-        loader_platform_thread_init_cond(&threadingCond);
-        threadingLockInitialized = 1;
-    }
 }
 
 VK_LAYER_EXPORT VKAPI_ATTR VkResult VKAPI_CALL
@@ -102,12 +96,6 @@
     layer_debug_report_destroy_instance(my_data->report_data);
     delete my_data->instance_dispatch_table;
     layer_data_map.erase(key);
-
-    if (layer_data_map.empty()) {
-        // Release mutex when destroying last instance.
-        loader_platform_thread_delete_mutex(&threadingLock);
-        threadingLockInitialized = 0;
-    }
 }
 
 VK_LAYER_EXPORT VKAPI_ATTR VkResult VKAPI_CALL vkCreateDevice(VkPhysicalDevice gpu, const VkDeviceCreateInfo *pCreateInfo,
@@ -311,9 +299,8 @@
     // Record mapping from command buffer to command pool
     if (VK_SUCCESS == result) {
         for (uint32_t index = 0; index < pAllocateInfo->commandBufferCount; index++) {
-            loader_platform_thread_lock_mutex(&threadingLock);
+            std::lock_guard<std::mutex> lock(global_lock);
             command_pool_map[pCommandBuffers[index]] = pAllocateInfo->commandPool;
-            loader_platform_thread_unlock_mutex(&threadingLock);
         }
     }
 
@@ -337,8 +324,7 @@
     finishWriteObject(my_data, commandPool);
     for (uint32_t index = 0; index < commandBufferCount; index++) {
         finishWriteObject(my_data, pCommandBuffers[index], lockCommandPool);
-        loader_platform_thread_lock_mutex(&threadingLock);
+        std::lock_guard<std::mutex> lock(global_lock);
         command_pool_map.erase(pCommandBuffers[index]);
-        loader_platform_thread_unlock_mutex(&threadingLock);
     }
 }