Fix race condition of removing surface.
mContainer.startingSurface can be replaced between posting
mRemoveStartingWindow and actually surface.remove() is called.
1. removeStartingWindow is called, then mRemoveStartingWindow is posted
to mHandler
2. transferStartingWindow is called, then mContainer.startingWindow is
replaced with new surface.
3. mHandler pops the callback and surface.remove() is called.
Here the remove is only called for replaced surface and never called for
older surface.
To fix this issue, surely removes the surface when the
removeStartingWindow is called.
Bug: 63156080
Bug: 63784898
Test: Watch /proc/<pid>/fd
Change-Id: Iccf13bdc98b4012168910305568f5dd4bbedbf54
Merged-In: I55e2c1b8fba32b3a19603e6ad4743f07576abd48
(cherry picked from commit 0bf3dc9822a4817b1fea1d819ab7abf61013ad8b)
diff --git a/services/core/java/com/android/server/wm/AppWindowContainerController.java b/services/core/java/com/android/server/wm/AppWindowContainerController.java
index 4e4398e..741161b 100644
--- a/services/core/java/com/android/server/wm/AppWindowContainerController.java
+++ b/services/core/java/com/android/server/wm/AppWindowContainerController.java
@@ -115,41 +115,6 @@
mListener.onWindowsGone();
};
- private final Runnable mRemoveStartingWindow = () -> {
- StartingSurface surface = null;
- synchronized (mWindowMap) {
- if (mContainer == null) {
- if (DEBUG_STARTING_WINDOW) Slog.v(TAG_WM, "mContainer was null while trying to"
- + " remove starting window");
- return;
- }
- if (DEBUG_STARTING_WINDOW) Slog.v(TAG_WM, "Remove starting " + mContainer
- + ": startingWindow=" + mContainer.startingWindow
- + " startingView=" + mContainer.startingSurface);
- if (mContainer.startingData != null) {
- surface = mContainer.startingSurface;
- mContainer.startingData = null;
- mContainer.startingSurface = null;
- mContainer.startingWindow = null;
- mContainer.startingDisplayed = false;
- if (surface == null && DEBUG_STARTING_WINDOW) {
- Slog.v(TAG_WM, "startingWindow was set but startingSurface==null, couldn't "
- + "remove");
- }
- } else if (DEBUG_STARTING_WINDOW) {
- Slog.v(TAG_WM, "Tried to remove starting window but startingWindow was null:"
- + mContainer);
- }
- }
- if (surface != null) {
- try {
- surface.remove();
- } catch (Exception e) {
- Slog.w(TAG_WM, "Exception when removing starting window", e);
- }
- }
- };
-
private final Runnable mAddStartingWindow = () -> {
final StartingData startingData;
final AppWindowToken container;
@@ -649,13 +614,6 @@
public void removeStartingWindow() {
synchronized (mWindowMap) {
- if (mHandler.hasCallbacks(mRemoveStartingWindow)) {
- // Already scheduled.
- if (DEBUG_STARTING_WINDOW) Slog.v(TAG_WM, "Trying to remove starting window but "
- + "already scheduled");
- return;
- }
-
if (mContainer.startingWindow == null) {
if (mContainer.startingData != null) {
// Starting window has not been added yet, but it is scheduled to be added.
@@ -667,9 +625,36 @@
return;
}
+ final StartingSurface surface;
+ if (mContainer.startingData != null) {
+ surface = mContainer.startingSurface;
+ mContainer.startingData = null;
+ mContainer.startingSurface = null;
+ mContainer.startingWindow = null;
+ mContainer.startingDisplayed = false;
+ if (surface == null && DEBUG_STARTING_WINDOW) {
+ Slog.v(TAG_WM, "startingWindow was set but startingSurface==null, couldn't "
+ + "remove");
+ }
+ } else {
+ if (DEBUG_STARTING_WINDOW) {
+ Slog.v(TAG_WM, "Tried to remove starting window but startingWindow was null:"
+ + mContainer);
+ }
+ return;
+ }
+
if (DEBUG_STARTING_WINDOW) Slog.v(TAG_WM, "Schedule remove starting " + mContainer
- + " startingWindow=" + mContainer.startingWindow);
- mHandler.post(mRemoveStartingWindow);
+ + " startingWindow=" + mContainer.startingWindow
+ + " startingView=" + mContainer.startingSurface);
+ mHandler.post(() -> {
+ if (DEBUG_STARTING_WINDOW) Slog.v(TAG_WM, "Removing startingView=" + surface);
+ try {
+ surface.remove();
+ } catch (Exception e) {
+ Slog.w(TAG_WM, "Exception when removing starting window", e);
+ }
+ });
}
}
