From 9b47623790d9ee71973a4c502d4851a36efcd04f Mon Sep 17 00:00:00 2001
From: Yandry Perez Clemente <yandry@google.com>
Date: Fri, 26 Nov 2021 11:14:28 +0000
Subject: [PATCH] Adds trace messages when goAsync and finish are called.

These will be used to troubleshoot ANRs. In this case calling goAsync
and forgetting to call finish on the PendingResult could be the cause.
We have existing instrumentation to include these in Perfetto traces
and have used the "am" tag to avoid having to allowlist every single
app of interest in the Perfetto tracing configuration (the "am" tag is
allowlisted).

Test: Manual: captured a Perfetto trace and verified the counters are
present.
Bug: b/207823767

Change-Id: I96aadf4d6d891f3c7d140b9792e7f893243d9943
---
 core/java/android/content/BroadcastReceiver.java | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/core/java/android/content/BroadcastReceiver.java b/core/java/android/content/BroadcastReceiver.java
index 1d4d30d875601..f335ae483bf7e 100644
--- a/core/java/android/content/BroadcastReceiver.java
+++ b/core/java/android/content/BroadcastReceiver.java
@@ -27,6 +27,7 @@ import android.os.Build;
 import android.os.Bundle;
 import android.os.IBinder;
 import android.os.RemoteException;
+import android.os.Trace;
 import android.os.UserHandle;
 import android.util.Log;
 import android.util.Slog;
@@ -98,6 +99,7 @@ public abstract class BroadcastReceiver {
         boolean mAbortBroadcast;
         @UnsupportedAppUsage
         boolean mFinished;
+        String mReceiverClassName;
 
         /** @hide */
         @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
@@ -219,6 +221,12 @@ public abstract class BroadcastReceiver {
          * next broadcast will proceed.
          */
         public final void finish() {
+            if (Trace.isTagEnabled(Trace.TRACE_TAG_ACTIVITY_MANAGER)) {
+                Trace.traceCounter(Trace.TRACE_TAG_ACTIVITY_MANAGER,
+                        "PendingResult#finish#ClassName:" + mReceiverClassName,
+                        1);
+            }
+
             if (mType == TYPE_COMPONENT) {
                 final IActivityManager mgr = ActivityManager.getService();
                 if (QueuedWork.hasPendingWork()) {
@@ -383,6 +391,14 @@ public abstract class BroadcastReceiver {
     public final PendingResult goAsync() {
         PendingResult res = mPendingResult;
         mPendingResult = null;
+
+        if (Trace.isTagEnabled(Trace.TRACE_TAG_ACTIVITY_MANAGER)) {
+            res.mReceiverClassName = getClass().getName();
+            Trace.traceCounter(Trace.TRACE_TAG_ACTIVITY_MANAGER,
+                    "BroadcastReceiver#goAsync#ClassName:" + res.mReceiverClassName,
+                    1);
+        }
+
         return res;
     }