fix race condition between HWUI cache and renderThread

getMaximumBitmapWidth() and getMaximumBitmapHeight() of DisplayListCanvas
need HWUI cache instance. Since the initialization of the cache is
asynchronous it may crash if not yet ready. Add a staticFence() call
to guarantee the cache has been created prior issuing the call.

Change-Id: I5ed9e5cc084444c8d1872a77fef50e294ae14e93
Signed-off-by: Thomas Buhot <thomas.buhot@intel.com>
Signed-off-by: Zhiquan Liu <zhiquan.liu@intel.com>

3 files changed, 13 insertions, 0 deletions

diff --git a/core/jni/android_view_DisplayListCanvas.cpp b/core/jni/android_view_DisplayListCanvas.cpp
index bb8ef83c3f8..ef1e4abdf14 100644
--- a/core/jni/android_view_DisplayListCanvas.cpp
+++ b/core/jni/android_view_DisplayListCanvas.cpp
@@ -102,10 +102,16 @@ static void android_view_DisplayListCanvas_callDrawGLFunction(JNIEnv* env, jobje
 // ----------------------------------------------------------------------------
 
 static jint android_view_DisplayListCanvas_getMaxTextureWidth(JNIEnv* env, jobject clazz) {
+    if (!Caches::hasInstance()) {
+        android::uirenderer::renderthread::RenderProxy::staticFence();
+    }
     return Caches::getInstance().maxTextureSize;
 }
 
 static jint android_view_DisplayListCanvas_getMaxTextureHeight(JNIEnv* env, jobject clazz) {
+    if (!Caches::hasInstance()) {
+        android::uirenderer::renderthread::RenderProxy::staticFence();
+    }
     return Caches::getInstance().maxTextureSize;
 }
 
diff --git a/libs/hwui/renderthread/RenderProxy.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index 939c0c781fc..22140917d5b 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -389,6 +389,12 @@ void RenderProxy::fence() {
     postAndWait(task);
 }
 
+void RenderProxy::staticFence() {
+    SETUP_TASK(fence);
+    UNUSED(args);
+    staticPostAndWait(task);
+}
+
 CREATE_BRIDGE1(stopDrawing, CanvasContext* context) {
     args->context->stopDrawing();
     return nullptr;
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index db03b29f134..8a1f5bf4fa4 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -94,6 +94,7 @@ public:
     ANDROID_API static void overrideProperty(const char* name, const char* value);
 
     ANDROID_API void fence();
+    ANDROID_API static void staticFence();
     ANDROID_API void stopDrawing();
     ANDROID_API void notifyFramePending();