commit c889d3c5763d34ecfff99cff8df1c6e85aac00d0
author Yiwei Zhang <zzyiwei@google.com> Thu Jul 16 13:51:12 2020 -0700
committer Yiwei Zhang <zzyiwei@google.com> Thu Jul 16 15:45:36 2020 -0700
tree d4dd65f8af9cc8a4fb9f42b01fbfadb9dc3b15bf
parent 8dcf124c0894e90b932ff5501892dacc37f36fad

libvulkan: make vkEnumerateInstanceVersion trigger driver loading

This is a globally dispatched api, and it's the best option to preload
the driver in Zygote with minimum overhead.

This change also updates some return codes according to the spec.

Bug: 135536511
Test: take a trace and verify driver is loaded
Change-Id: I6fe425ec568b13577d3d9471aa5f181cff44c61c

vulkan/libvulkan/api.cpp

diff --git a/vulkan/libvulkan/api.cpp b/vulkan/libvulkan/api.cpp
index 5b9affd..80166c8 100644
--- a/vulkan/libvulkan/api.cpp
+++ b/vulkan/libvulkan/api.cpp
@@ -1256,7 +1256,7 @@
     ATRACE_CALL();
 
     if (!EnsureInitialized())
-        return VK_ERROR_INITIALIZATION_FAILED;
+        return VK_ERROR_OUT_OF_HOST_MEMORY;
 
     uint32_t count = GetLayerCount();
 
@@ -1280,7 +1280,7 @@
     ATRACE_CALL();
 
     if (!EnsureInitialized())
-        return VK_ERROR_INITIALIZATION_FAILED;
+        return VK_ERROR_OUT_OF_HOST_MEMORY;
 
     if (pLayerName) {
         const Layer* layer = FindLayer(pLayerName);
@@ -1456,6 +1456,11 @@
 VkResult EnumerateInstanceVersion(uint32_t* pApiVersion) {
     ATRACE_CALL();
 
+    // Load the driver here if not done yet. This api will be used in Zygote
+    // for Vulkan driver pre-loading because of the minimum overhead.
+    if (!EnsureInitialized())
+        return VK_ERROR_OUT_OF_HOST_MEMORY;
+
     *pApiVersion = VK_API_VERSION_1_1;
     return VK_SUCCESS;
 }