commit 9957151661b8ae65da45a1fb72df5b66176302cb
author Makoto Onuki <omakoto@google.com> Tue Mar 28 14:12:34 2017 -0700
committer Makoto Onuki <omakoto@google.com> Tue Mar 28 21:49:51 2017 +0000
tree 24c2097a1d8d174a2e6e7ae82a8c05b81c89188f
parent 881a623e3522e3e4f0905b606ca5c77cf899b21c

Log a warning if a dispatch on UiThread takes more than

a certain amount of time.

Bug: 34961340
Test: Boot and launch several apps.
Change-Id: I38bd85a1dd9c572242d04f550df4a979f5f3bea5

services/core/java/com/android/server/UiThread.java

diff --git a/services/core/java/com/android/server/UiThread.java b/services/core/java/com/android/server/UiThread.java
index 1bc6250..f1581ad 100644
--- a/services/core/java/com/android/server/UiThread.java
+++ b/services/core/java/com/android/server/UiThread.java
@@ -17,6 +17,7 @@
 package com.android.server;
 
 import android.os.Handler;
+import android.os.Looper;
 import android.os.Process;
 import android.os.Trace;
 
@@ -26,6 +27,7 @@
  * on it to avoid UI jank.
  */
 public final class UiThread extends ServiceThread {
+    private static final long SLOW_DISPATCH_THRESHOLD_MS = 100;
     private static UiThread sInstance;
     private static Handler sHandler;
 
@@ -39,7 +41,9 @@
         if (sInstance == null) {
             sInstance = new UiThread();
             sInstance.start();
-            sInstance.getLooper().setTraceTag(Trace.TRACE_TAG_ACTIVITY_MANAGER);
+            final Looper looper = sInstance.getLooper();
+            looper.setTraceTag(Trace.TRACE_TAG_ACTIVITY_MANAGER);
+            looper.setSlowDispatchThresholdMs(SLOW_DISPATCH_THRESHOLD_MS);
             sHandler = new Handler(sInstance.getLooper());
         }
     }