From f7b8d687bf6cc3d0109b9003631851c5698fdafa Mon Sep 17 00:00:00 2001
From: Rambo Wang <rambowang@google.com>
Date: Fri, 16 Jun 2023 02:16:08 +0000
Subject: [PATCH] Fix Settings app ANR due to blocking IDumpstateDevice IPC
 call

This CL fixes the ANR by moving possible blocking IDumpstateDevice
IPC call from main thread to background thread.

Settings develop options depends on IDumpstateDevice IPC call to
set and get Vendor Verbose Logging feature. The IPC may occasionally
get blocked in system_server which is extremely busy (e.g. during
bugreport generating). This may cause Settings app crashing with ANR.

Bug: 287126040
Bug: 280015761
Test: atest EnableVerboseVendorLoggingPreferenceControllerTest
Test: Verbose Vendor Logging regression
Test: Stress test (heavily trigger on/off during BR generating)
Change-Id: I0b88ef089097930b62dcb1cb7d6fe9990356ab5d
---
 ...boseVendorLoggingPreferenceController.java | 20 +++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/com/android/settings/development/EnableVerboseVendorLoggingPreferenceController.java b/src/com/android/settings/development/EnableVerboseVendorLoggingPreferenceController.java
index 051cede54b5..f13143dfdce 100644
--- a/src/com/android/settings/development/EnableVerboseVendorLoggingPreferenceController.java
+++ b/src/com/android/settings/development/EnableVerboseVendorLoggingPreferenceController.java
@@ -29,6 +29,7 @@ import androidx.preference.SwitchPreference;
 
 import com.android.settings.core.PreferenceControllerMixin;
 import com.android.settingslib.development.DeveloperOptionsPreferenceController;
+import com.android.settingslib.utils.ThreadUtils;
 
 import java.util.NoSuchElementException;
 
@@ -66,23 +67,34 @@ public class EnableVerboseVendorLoggingPreferenceController
         return isIDumpstateDeviceAidlServiceAvailable() || isIDumpstateDeviceV1_1ServiceAvailable();
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     @Override
     public boolean onPreferenceChange(Preference preference, Object newValue) {
         final boolean isEnabled = (Boolean) newValue;
-        setVerboseLoggingEnabled(isEnabled);
+        // IDumpstateDevice IPC may be blocking when system is extremely heavily-loaded.
+        // Post to background thread to avoid ANR. Ignore the returned Future.
+        ThreadUtils.postOnBackgroundThread(() ->
+                setVerboseLoggingEnabled(isEnabled));
         return true;
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     @Override
     public void updateState(Preference preference) {
-        final boolean enabled = getVerboseLoggingEnabled();
-        ((SwitchPreference) mPreference).setChecked(enabled);
+        ThreadUtils.postOnBackgroundThread(() -> {
+                    final boolean enabled = getVerboseLoggingEnabled();
+                    ThreadUtils.getUiThreadHandler().post(() ->
+                            ((SwitchPreference) mPreference).setChecked(enabled));
+                }
+        );
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     @Override
     protected void onDeveloperOptionsSwitchDisabled() {
         super.onDeveloperOptionsSwitchDisabled();
-        setVerboseLoggingEnabled(false);
+        ThreadUtils.postOnBackgroundThread(() ->
+                setVerboseLoggingEnabled(false));
         ((SwitchPreference) mPreference).setChecked(false);
     }