GLSurfaceView pause and resume now synchronize

with the GLThread.

We used to just set the mPaused state and return,
now we wait until the rendering thread signals
that it has noticed the change in pause state.

This makes Pause/Resume more consistent with
other UI-thread-to-GLThread event communication.

This change was made in the hope of fixing some
race conditions observed in monkey testing.

1 files changed, 41 insertions, 3 deletions

diff --git a/opengl/java/android/opengl/GLSurfaceView.java b/opengl/java/android/opengl/GLSurfaceView.java
index 1b99e78..0f79b15 100644
--- a/opengl/java/android/opengl/GLSurfaceView.java
+++ b/opengl/java/android/opengl/GLSurfaceView.java
@@ -158,7 +158,7 @@ public class GLSurfaceView extends SurfaceView implements SurfaceHolder.Callback
     private final static boolean LOG_THREADS = false;
     private final static boolean LOG_PAUSE_RESUME = true;
     private final static boolean LOG_SURFACE = true;
-    private final static boolean LOG_RENDERER = false;
+    private final static boolean LOG_RENDERER = true;
     private final static boolean LOG_RENDERER_DRAW_FRAME = false;
     private final static boolean LOG_EGL = true;
     // Work-around for bug 2263168
@@ -1161,6 +1161,15 @@ public class GLSurfaceView extends SurfaceView implements SurfaceHolder.Callback
                                 break;
                             }
 
+                            // Update the pause state.
+                            if (mPaused != mRequestPaused) {
+                                mPaused = mRequestPaused;
+                                sGLThreadManager.notifyAll();
+                                if (LOG_PAUSE_RESUME) {
+                                    Log.i("GLThread", "mPaused is now " + mPaused + " tid=" + getId());
+                                }
+                            }
+
                             // Have we lost the EGL context?
                             if (lostEglContext) {
                                 stopEglSurfaceLocked();
@@ -1360,6 +1369,13 @@ public class GLSurfaceView extends SurfaceView implements SurfaceHolder.Callback
                 }
                 mHasSurface = true;
                 sGLThreadManager.notifyAll();
+                while((mWaitingForSurface) && (!mExited)) {
+                    try {
+                        sGLThreadManager.wait();
+                    } catch (InterruptedException e) {
+                        Thread.currentThread().interrupt();
+                    }
+                }
             }
         }
 
@@ -1385,8 +1401,18 @@ public class GLSurfaceView extends SurfaceView implements SurfaceHolder.Callback
                 if (LOG_PAUSE_RESUME) {
                     Log.i("GLThread", "onPause tid=" + getId());
                 }
-                mPaused = true;
+                mRequestPaused = true;
                 sGLThreadManager.notifyAll();
+                while ((! mExited) && (! mPaused)) {
+                    if (LOG_PAUSE_RESUME) {
+                        Log.i("Main thread", "onPause waiting for mPaused.");
+                    }
+                    try {
+                        sGLThreadManager.wait();
+                    } catch (InterruptedException ex) {
+                        Thread.currentThread().interrupt();
+                    }
+                }
             }
         }
 
@@ -1395,9 +1421,20 @@ public class GLSurfaceView extends SurfaceView implements SurfaceHolder.Callback
                 if (LOG_PAUSE_RESUME) {
                     Log.i("GLThread", "onResume tid=" + getId());
                 }
-                mPaused = false;
+                mRequestPaused = false;
                 mRequestRender = true;
+                mRenderComplete = false;
                 sGLThreadManager.notifyAll();
+                while ((! mExited) && mPaused && (!mRenderComplete)) {
+                    if (LOG_PAUSE_RESUME) {
+                        Log.i("Main thread", "onResume waiting for !mPaused.");
+                    }
+                    try {
+                        sGLThreadManager.wait();
+                    } catch (InterruptedException ex) {
+                        Thread.currentThread().interrupt();
+                    }
+                }
             }
         }
 
@@ -1458,6 +1495,7 @@ public class GLSurfaceView extends SurfaceView implements SurfaceHolder.Callback
         // variables are protected by the sGLThreadManager monitor
         private boolean mShouldExit;
         private boolean mExited;
+        private boolean mRequestPaused;
         private boolean mPaused;
         private boolean mHasSurface;
         private boolean mWaitingForSurface;