Vulkan: unload builtin driver to reload updated driver if needed
Android historically preloads GL driver in Zygote to speed up app launch
time and avoid the duplicate extra memory for each process loading the
graphics driver. In Android 10, we landed GL driver unloading mechanism
to ship updatable driver and ANGLE without perf overhead on the rest of
the system.
To get prepared for the HWUI Vulkan backend being turned on as the
default renderer for UI componments, this CL will do the same to the
Vulkan driver to preload it in Zygote and unload so to reload updated
driver if needed.
Bug: 135536511
Test: atest CtsUiRenderingTestCases no regression on VK backend
Change-Id: I2909f6ecc4f011b1f3670aacdf817ed3b6e9a487
diff --git a/vulkan/libvulkan/api.cpp b/vulkan/libvulkan/api.cpp
index 80166c8..2d4690a 100644
--- a/vulkan/libvulkan/api.cpp
+++ b/vulkan/libvulkan/api.cpp
@@ -1174,23 +1174,18 @@
// ----------------------------------------------------------------------------
bool EnsureInitialized() {
- static std::once_flag once_flag;
- static bool initialized;
+ static bool initialized = false;
+ static pid_t init_attempted_for_pid = 0;
+ static std::mutex init_lock;
- std::call_once(once_flag, []() {
- if (driver::OpenHAL()) {
- initialized = true;
- }
- });
+ std::lock_guard<std::mutex> lock(init_lock);
+ if (init_attempted_for_pid == getpid())
+ return initialized;
- {
- static pid_t pid = getpid() + 1;
- static std::mutex layer_lock;
- std::lock_guard<std::mutex> lock(layer_lock);
- if (pid != getpid()) {
- pid = getpid();
- DiscoverLayers();
- }
+ init_attempted_for_pid = getpid();
+ if (driver::OpenHAL()) {
+ DiscoverLayers();
+ initialized = true;
}
return initialized;