android: Record the memory size of the GSA process.

chrome/android/java/src/org/chromium/chrome/browser/gsa/GSAServiceClient.java

Index: chrome/android/java/src/org/chromium/chrome/browser/gsa/GSAServiceClient.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/gsa/GSAServiceClient.java b/chrome/android/java/src/org/chromium/chrome/browser/gsa/GSAServiceClient.java
index 688c52f1268a996ef84465233481a02cc5a1d19a..b82a90998561d7e422b5b8532f541162d7d85df6 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/gsa/GSAServiceClient.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/gsa/GSAServiceClient.java
@@ -5,11 +5,14 @@
 package org.chromium.chrome.browser.gsa;
 
 import android.annotation.SuppressLint;
+import android.app.ActivityManager;
 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.content.ServiceConnection;
+import android.os.AsyncTask;
 import android.os.Bundle;
+import android.os.Debug;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.Message;
@@ -18,9 +21,15 @@ import android.os.RemoteException;
 import android.util.Log;
 
 import org.chromium.base.Callback;
+import org.chromium.base.ContextUtils;
+import org.chromium.base.TraceEvent;
+import org.chromium.base.VisibleForTesting;
 import org.chromium.base.annotations.SuppressFBWarnings;
+import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.chrome.browser.ChromeApplication;
 
+import java.util.List;
+
 /**
  * A simple client that connects and talks to the GSAService using Messages.
  */
@@ -31,8 +40,8 @@ public class GSAServiceClient {
      * Constants for gsa communication. These should not change without corresponding changes on the
      * service side in GSA.
      */
-    private static final String GSA_SERVICE =
-            "com.google.android.ssb.action.SSB_SERVICE";
+    @VisibleForTesting
+    static final String GSA_SERVICE = "com.google.android.ssb.action.SSB_SERVICE";
     public static final int REQUEST_REGISTER_CLIENT = 2;
     public static final int RESPONSE_UPDATE_SSB = 3;
 
@@ -40,6 +49,10 @@ public class GSAServiceClient {
     public static final String KEY_GSA_CONTEXT = "ssb_service:ssb_context";
     public static final String KEY_GSA_PACKAGE_NAME = "ssb_service:ssb_package_name";
 
+    @VisibleForTesting
+    static final int INVALID_PSS = -1;
+
+    private static boolean sHasRecordedPss;
     /** Messenger to handle incoming messages from the service */
     private final Messenger mMessenger;
     private final IncomingHandler mHandler;
@@ -50,7 +63,7 @@ public class GSAServiceClient {
 
     /** Messenger for communicating with service. */
     private Messenger mService;
-
+    private ComponentName mComponentName;
 
     /**
      * Handler of incoming messages from service.
@@ -60,17 +73,85 @@ public class GSAServiceClient {
     private class IncomingHandler extends Handler {
         @Override
         public void handleMessage(Message msg) {
-            if (msg.what == RESPONSE_UPDATE_SSB) {
-                if (mService == null) return;
-                Bundle bundle = (Bundle) msg.obj;
-                String account =
-                        mGsaHelper.getGSAAccountFromState(bundle.getByteArray(KEY_GSA_STATE));
-                GSAState.getInstance(mContext.getApplicationContext()).setGsaAccount(account);
-                if (mOnMessageReceived != null) mOnMessageReceived.onResult(bundle);
-            } else {
+            if (msg.what != RESPONSE_UPDATE_SSB) {
                 super.handleMessage(msg);
+                return;
+            }
+
+            if (mService == null) return;
+            final Bundle bundle = (Bundle) msg.obj;
+            String account = mGsaHelper.getGSAAccountFromState(bundle.getByteArray(KEY_GSA_STATE));
+            GSAState.getInstance(mContext.getApplicationContext()).setGsaAccount(account);
+            if (sHasRecordedPss) {
+                if (mOnMessageReceived != null) mOnMessageReceived.onResult(bundle);
+                return;
+            }
+
+            // Getting the PSS for the GSA service process can be long, don't block the UI thread on
+            // that. Also, don't process the callback before the PSS is known, since the callback
+            // can lead to a service disconnect, which can lead to the framework killing the
+            // process. Hence an AsyncTask (long operation), and processing the callback in
+            // onPostExecute() (don't disconnect before).
+            sHasRecordedPss = true;
+            new AsyncTask<Void, Void, Integer>() {
+                @Override
+                protected Integer doInBackground(Void... params) {
+                    TraceEvent.begin("GSAServiceClient.getPssForservice");
+                    try {
+                        // Looking for the service process is done by component name, which is
+                        // inefficient. We really want the PID, which is only accessible from within
+                        // a Binder transaction. Since the service connection is Messenger-based,
+                        // the calls are not processed from a Binder thread. The alternatives are:
+                        // 1. Override methods in the framework to append the calling PID to the
+                        //    Message.
+                        // 2. Usse msg.callingUid to narrow down the search.
+                        //
+                        // (1) is dirty (and brittle), and (2) only works on L+, and still requires
+                        // to get the full list of services from ActivityManager.
+                        return getPssForService(mComponentName);
+                    } finally {
+                        TraceEvent.end("GSAServiceClient.getPssForservice");
+                    }
+                }
+
+                @Override
+                protected void onPostExecute(Integer pssInKB) {
+                    if (pssInKB != INVALID_PSS) {
+                        RecordHistogram.recordMemoryKBHistogram(
+                                "Search.GsaProcessMemoryPss", pssInKB);
+                    }
+                    if (mOnMessageReceived != null) mOnMessageReceived.onResult(bundle);
+                }
+            }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
+        }
+    }
+
+    /**
+     * Get the PSS used by the process hosting a service.
+     *
+     * @param packageName Package name of the service to search for.
+     * @return the PSS in kB of the process hosting a service, or INVALID_PSS.
+     */
+    @VisibleForTesting
+    static int getPssForService(ComponentName componentName) {
+        if (componentName == null) return INVALID_PSS;
+        Context context = ContextUtils.getApplicationContext();
+        ActivityManager activityManager =
+                (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
+        List<ActivityManager.RunningServiceInfo> services =
+                activityManager.getRunningServices(1000);
+        if (services == null) return INVALID_PSS;
+        int pid = -1;
+        for (ActivityManager.RunningServiceInfo info : services) {
+            if (componentName.equals(info.service)) {
+                pid = info.pid;
+                break;
             }
         }
+        if (pid == -1) return INVALID_PSS;
+        Debug.MemoryInfo infos[] = activityManager.getProcessMemoryInfo(new int[] {pid});
+        if (infos == null || infos.length == 0) return INVALID_PSS;
+        return infos[0].getTotalPss();
     }
 
     /**
@@ -137,6 +218,7 @@ public class GSAServiceClient {
             if (mContext == null) return;
 
             mService = new Messenger(service);
+            mComponentName = name;
             try {
                 Message registerClientMessage = Message.obtain(
                         null, REQUEST_REGISTER_CLIENT);