Make stopped state a first-class thing

Bug: 27286867

WindowManager has committed to stopped state
controlling the lifecycle of the Surface, so
make that a first-class thing in HWUI as well.

This makes it more resistent to things like
a rogue updateSurface() happening while mStopped=true,
leading to bad things down the line. Instead let
the surface be changed/updated as often as desired,
and just block any attempt to draw on that surface.

Also removes some unnecessary makeCurrent()s, as
EglManager ensures that we *always* have a valid
GL context now (using a pbuffer surface if there is
no window surface set)

Change-Id: Iead78ddebc7997e8fdb0c9534836352f5e54b9bd
diff --git a/core/java/android/view/ThreadedRenderer.java b/core/java/android/view/ThreadedRenderer.java
index df774b4..87b9a00 100644
--- a/core/java/android/view/ThreadedRenderer.java
+++ b/core/java/android/view/ThreadedRenderer.java
@@ -485,15 +485,25 @@
     }
 
     /**
-     * Stops any rendering into the surface. Use this if it is unclear whether
+     * Halts any current rendering into the surface. Use this if it is unclear whether
      * or not the surface used by the HardwareRenderer will be changing. It
-     * Suspends any rendering into the surface, but will not do any destruction
+     * Suspends any rendering into the surface, but will not do any destruction.
+     *
+     * Any subsequent draws will override the pause, resuming normal operation.
      */
     boolean pauseSurface(Surface surface) {
         return nPauseSurface(mNativeProxy, surface);
     }
 
     /**
+     * Hard stops or resumes rendering into the surface. This flag is used to
+     * determine whether or not it is safe to use the given surface *at all*
+     */
+    void setStopped(boolean stopped) {
+        nSetStopped(mNativeProxy, stopped);
+    }
+
+    /**
      * Destroys all hardware rendering resources associated with the specified
      * view hierarchy.
      *
@@ -989,6 +999,7 @@
     private static native void nInitialize(long nativeProxy, Surface window);
     private static native void nUpdateSurface(long nativeProxy, Surface window);
     private static native boolean nPauseSurface(long nativeProxy, Surface window);
+    private static native void nSetStopped(long nativeProxy, boolean stopped);
     private static native void nSetup(long nativeProxy, int width, int height,
             float lightRadius, int ambientShadowAlpha, int spotShadowAlpha);
     private static native void nSetLightCenter(long nativeProxy,
diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index 5b2877f..5626f01 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -1079,13 +1079,16 @@
     void setWindowStopped(boolean stopped) {
         if (mStopped != stopped) {
             mStopped = stopped;
+            final ThreadedRenderer renderer = mAttachInfo.mHardwareRenderer;
+            if (renderer != null) {
+                if (DEBUG_DRAW) Log.d(mTag, "WindowStopped on " + getTitle() + " set to " + mStopped);
+                renderer.setStopped(mStopped);
+            }
             if (!mStopped) {
                 scheduleTraversals();
             } else {
-                if (mAttachInfo.mHardwareRenderer != null) {
-                    if (DEBUG_DRAW) Log.d(mTag, "WindowStopped on " + getTitle());
-                    mAttachInfo.mHardwareRenderer.updateSurface(null);
-                    mAttachInfo.mHardwareRenderer.destroyHardwareResources(mView);
+                if (renderer != null) {
+                    renderer.destroyHardwareResources(mView);
                 }
             }
         }
diff --git a/core/jni/android_view_ThreadedRenderer.cpp b/core/jni/android_view_ThreadedRenderer.cpp
index 8019326..46411e1 100644
--- a/core/jni/android_view_ThreadedRenderer.cpp
+++ b/core/jni/android_view_ThreadedRenderer.cpp
@@ -481,6 +481,12 @@
     return proxy->pauseSurface(surface);
 }
 
+static void android_view_ThreadedRenderer_setStopped(JNIEnv* env, jobject clazz,
+        jlong proxyPtr, jboolean stopped) {
+    RenderProxy* proxy = reinterpret_cast<RenderProxy*>(proxyPtr);
+    proxy->setStopped(stopped);
+}
+
 static void android_view_ThreadedRenderer_setup(JNIEnv* env, jobject clazz, jlong proxyPtr,
         jint width, jint height, jfloat lightRadius, jint ambientShadowAlpha, jint spotShadowAlpha) {
     RenderProxy* proxy = reinterpret_cast<RenderProxy*>(proxyPtr);
@@ -733,6 +739,7 @@
     { "nInitialize", "(JLandroid/view/Surface;)V", (void*) android_view_ThreadedRenderer_initialize },
     { "nUpdateSurface", "(JLandroid/view/Surface;)V", (void*) android_view_ThreadedRenderer_updateSurface },
     { "nPauseSurface", "(JLandroid/view/Surface;)Z", (void*) android_view_ThreadedRenderer_pauseSurface },
+    { "nSetStopped", "(JZ)V", (void*) android_view_ThreadedRenderer_setStopped },
     { "nSetup", "(JIIFII)V", (void*) android_view_ThreadedRenderer_setup },
     { "nSetLightCenter", "(JFFF)V", (void*) android_view_ThreadedRenderer_setLightCenter },
     { "nSetOpaque", "(JZ)V", (void*) android_view_ThreadedRenderer_setOpaque },
diff --git a/libs/hwui/renderthread/CanvasContext.cpp b/libs/hwui/renderthread/CanvasContext.cpp
index 63fa788..8eea2f1 100644
--- a/libs/hwui/renderthread/CanvasContext.cpp
+++ b/libs/hwui/renderthread/CanvasContext.cpp
@@ -113,18 +113,11 @@
         mBufferPreserved = mEglManager.setPreserveBuffer(mEglSurface, preserveBuffer);
         mHaveNewSurface = true;
         mSwapHistory.clear();
-        makeCurrent();
     } else {
         mRenderThread.removeFrameCallback(this);
     }
 }
 
-void CanvasContext::requireSurface() {
-    LOG_ALWAYS_FATAL_IF(mEglSurface == EGL_NO_SURFACE,
-            "requireSurface() called but no surface set!");
-    makeCurrent();
-}
-
 void CanvasContext::setSwapBehavior(SwapBehavior swapBehavior) {
     mSwapBehavior = swapBehavior;
 }
@@ -146,6 +139,18 @@
     return mRenderThread.removeFrameCallback(this);
 }
 
+void CanvasContext::setStopped(bool stopped) {
+    if (mStopped != stopped) {
+        mStopped = stopped;
+        if (mStopped) {
+            mRenderThread.removeFrameCallback(this);
+            if (mEglManager.isCurrent(mEglSurface)) {
+                mEglManager.makeCurrent(EGL_NO_SURFACE);
+            }
+        }
+    }
+}
+
 // TODO: don't pass viewport size, it's automatic via EGL
 void CanvasContext::setup(int width, int height, float lightRadius,
         uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha) {
@@ -172,7 +177,9 @@
     mOpaque = opaque;
 }
 
-void CanvasContext::makeCurrent() {
+bool CanvasContext::makeCurrent() {
+    if (mStopped) return false;
+
     // TODO: Figure out why this workaround is needed, see b/13913604
     // In the meantime this matches the behavior of GLRenderer, so it is not a regression
     EGLint error = 0;
@@ -180,6 +187,7 @@
     if (error) {
         setSurface(nullptr);
     }
+    return !error;
 }
 
 static bool wasSkipped(FrameInfo* info) {
@@ -671,7 +679,7 @@
 }
 
 Layer* CanvasContext::createTextureLayer() {
-    requireSurface();
+    mEglManager.initialize();
     return LayerRenderer::createTextureLayer(mRenderThread.renderState());
 }
 
diff --git a/libs/hwui/renderthread/CanvasContext.h b/libs/hwui/renderthread/CanvasContext.h
index 6d0889e..525d5ef 100644
--- a/libs/hwui/renderthread/CanvasContext.h
+++ b/libs/hwui/renderthread/CanvasContext.h
@@ -82,13 +82,14 @@
     void initialize(Surface* surface);
     void updateSurface(Surface* surface);
     bool pauseSurface(Surface* surface);
+    void setStopped(bool stopped);
     bool hasSurface() { return mNativeSurface.get(); }
 
     void setup(int width, int height, float lightRadius,
             uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha);
     void setLightCenter(const Vector3& lightCenter);
     void setOpaque(bool opaque);
-    void makeCurrent();
+    bool makeCurrent();
     void prepareTree(TreeInfo& info, int64_t* uiFrameInfo,
             int64_t syncQueued, RenderNode* target);
     void draw();
@@ -172,7 +173,6 @@
     friend class android::uirenderer::RenderState;
 
     void setSurface(Surface* window);
-    void requireSurface();
 
     void freePrefetechedLayers();
 
@@ -185,6 +185,7 @@
     EglManager& mEglManager;
     sp<Surface> mNativeSurface;
     EGLSurface mEglSurface = EGL_NO_SURFACE;
+    bool mStopped = false;
     bool mBufferPreserved = false;
     SwapBehavior mSwapBehavior = kSwap_default;
     struct SwapHistory {
diff --git a/libs/hwui/renderthread/DrawFrameTask.cpp b/libs/hwui/renderthread/DrawFrameTask.cpp
index e8b9725..bd0c1dc0 100644
--- a/libs/hwui/renderthread/DrawFrameTask.cpp
+++ b/libs/hwui/renderthread/DrawFrameTask.cpp
@@ -113,7 +113,7 @@
     ATRACE_CALL();
     int64_t vsync = mFrameInfo[static_cast<int>(FrameInfoIndex::Vsync)];
     mRenderThread->timeLord().vsyncReceived(vsync);
-    mContext->makeCurrent();
+    bool canDraw = mContext->makeCurrent();
     Caches::getInstance().textureCache.resetMarkInUse(mContext);
 
     for (size_t i = 0; i < mLayers.size(); i++) {
@@ -124,8 +124,9 @@
 
     // This is after the prepareTree so that any pending operations
     // (RenderNode tree state, prefetched layers, etc...) will be flushed.
-    if (CC_UNLIKELY(!mContext->hasSurface())) {
+    if (CC_UNLIKELY(!mContext->hasSurface() || !canDraw)) {
         mSyncResult |= kSync_LostSurfaceRewardIfFound;
+        info.out.canDrawThisFrame = false;
     }
 
     if (info.out.hasAnimations) {
diff --git a/libs/hwui/renderthread/EglManager.cpp b/libs/hwui/renderthread/EglManager.cpp
index 8def7ad..ac6a28f 100644
--- a/libs/hwui/renderthread/EglManager.cpp
+++ b/libs/hwui/renderthread/EglManager.cpp
@@ -270,12 +270,6 @@
         // Ensure we always have a valid surface & context
         surface = mPBufferSurface;
     }
-    // TODO: Temporary to help diagnose b/27286867
-    if (mCurrentSurface == mPBufferSurface || surface == mPBufferSurface) {
-        ALOGD("Switching from surface %p%s to %p%s", mCurrentSurface,
-                mCurrentSurface == mPBufferSurface ? " (pbuffer)" : "",
-                        surface, surface == mPBufferSurface ? " (pbuffer)" : "");
-    }
     if (!eglMakeCurrent(mEglDisplay, surface, surface, mEglContext)) {
         if (errOut) {
             *errOut = eglGetError();
diff --git a/libs/hwui/renderthread/RenderProxy.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index 16dd108..149ddf6 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -175,6 +175,18 @@
     return (bool) postAndWait(task);
 }
 
+CREATE_BRIDGE2(setStopped, CanvasContext* context, bool stopped) {
+    args->context->setStopped(args->stopped);
+    return nullptr;
+}
+
+void RenderProxy::setStopped(bool stopped) {
+    SETUP_TASK(setStopped);
+    args->context = mContext;
+    args->stopped = stopped;
+    postAndWait(task);
+}
+
 CREATE_BRIDGE6(setup, CanvasContext* context, int width, int height,
         float lightRadius, uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha) {
     args->context->setup(args->width, args->height, args->lightRadius,
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index 8d65a82..3f35838 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -70,6 +70,7 @@
     ANDROID_API void initialize(const sp<Surface>& surface);
     ANDROID_API void updateSurface(const sp<Surface>& surface);
     ANDROID_API bool pauseSurface(const sp<Surface>& surface);
+    ANDROID_API void setStopped(bool stopped);
     ANDROID_API void setup(int width, int height, float lightRadius,
             uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha);
     ANDROID_API void setLightCenter(const Vector3& lightCenter);