customtabs: UMA histogram tracking whether clients call warmup().

chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.customtabs;
 
 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.content.ServiceConnection;
 import android.content.pm.PackageManager;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.os.SystemClock;
 import android.support.customtabs.ICustomTabsCallback;
 import android.text.TextUtils;
+import android.util.SparseBooleanArray;
 
 import org.chromium.base.ThreadUtils;
+import org.chromium.base.VisibleForTesting;
 import org.chromium.base.annotations.SuppressFBWarnings;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.chrome.browser.IntentHandler;
 import org.chromium.content_public.common.Referrer;
 
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
 /** Manages the clients' state for Custom Tabs. This class is threadsafe. */
 class ClientManager {
     // Values for the "CustomTabs.PredictionStatus" UMA histogram. Append-only.
     private static final int NO_PREDICTION = 0;
     private static final int GOOD_PREDICTION = 1;
     private static final int BAD_PREDICTION = 2;
     private static final int PREDICTION_STATUS_COUNT = 3;
+    // Values for the "CustomTabs.CalledWarmup" UMA histogram. Append-only.
+    @VisibleForTesting static final int NO_SESSION_NO_WARMUP = 0;
+    @VisibleForTesting static final int NO_SESSION_WARMUP = 1;
+    @VisibleForTesting static final int SESSION_NO_WARMUP_ALREADY_CALLED = 2;
+    @VisibleForTesting static final int SESSION_NO_WARMUP_NOT_CALLED = 3;
+    @VisibleForTesting static final int SESSION_WARMUP = 4;
+    @VisibleForTesting static final int SESSION_WARMUP_COUNT = 5;
 
     /** Per-session values. */
     private static class SessionParams {
         public final int uid;
         public final Referrer referrer;
         public final ICustomTabsCallback callback;
         public final IBinder.DeathRecipient deathRecipient;
         private ServiceConnection mKeepAliveConnection = null;
         private String mPredictedUrl = null;
         private long mLastMayLaunchUrlTimestamp = 0;
@@ skipping 33 matching lines @@
         public long getLastMayLaunchUrlTimestamp() {
             return mLastMayLaunchUrlTimestamp;
         }
     }
 
     /** To be called when a client gets disconnected. */
     public interface DisconnectCallback { public void run(IBinder session); }
 
     private final Context mContext;
     private final Map<IBinder, SessionParams> mSessionParams = new HashMap<>();
+    private final SparseBooleanArray mUidHasCalledWarmup = new SparseBooleanArray();
+    private boolean mWarmupHasBeenCalled = false;
 
     public ClientManager(Context context) {
         mContext = context.getApplicationContext();
         RequestThrottler.purgeOldEntries(mContext);
     }
 
     /** Creates a new session.
      *
      * @param cb Callback provided by the client.
      * @param uid Client UID, as returned by Binder.getCallingUid(),
@@ skipping 24 matching lines @@
             } catch (RemoteException e) {
                 // The return code doesn't matter, because this executes when
                 // the caller has died.
                 return false;
             }
             mSessionParams.put(session, params);
         }
         return true;
     }
 
+    @SuppressFBWarnings("CHROMIUM_SYNCHRONIZED_METHOD")
+    public synchronized void recordUidHasCalledWarmup(int uid) {
+        mWarmupHasBeenCalled = true;
+        mUidHasCalledWarmup.put(uid, true);
+    }
+
     /** Updates the client behavior stats and returns whether speculation is allowed.
      *
      * @param session Client session.
      * @param uid As returned by Binder.getCallingUid().
      * @param url Predicted URL.
      * @return true if speculation is allowed.
      */
     @SuppressFBWarnings("CHROMIUM_SYNCHRONIZED_METHOD")
     public synchronized boolean updateStatsAndReturnWhetherAllowed(
             IBinder session, int uid, String url) {
         SessionParams params = mSessionParams.get(session);
         if (params == null || params.uid != uid) return false;
         params.setPredictionMetrics(url, SystemClock.elapsedRealtime());
         RequestThrottler throttler = RequestThrottler.getForUid(mContext, uid);
         return throttler.updateStatsAndReturnWhetherAllowed();
     }
 
+    @VisibleForTesting
+    @SuppressFBWarnings("CHROMIUM_SYNCHRONIZED_METHOD")
+    synchronized int getWarmupState(IBinder session) {
+        SessionParams params = mSessionParams.get(session);
+        boolean hasValidSession = params != null;
+        boolean hasUidCalledWarmup = hasValidSession && mUidHasCalledWarmup.get(params.uid);
+        int result = mWarmupHasBeenCalled ? NO_SESSION_WARMUP : NO_SESSION_NO_WARMUP;
+        if (hasValidSession) {
+            if (hasUidCalledWarmup) {
+                result = SESSION_WARMUP;
+            } else {
+                result = mWarmupHasBeenCalled ? SESSION_NO_WARMUP_ALREADY_CALLED
+                                              : SESSION_NO_WARMUP_NOT_CALLED;
+            }
+        }
+        return result;
+    }
+
     /**
      * Registers that a client has launched a URL inside a Custom Tab.
      */
     @SuppressFBWarnings("CHROMIUM_SYNCHRONIZED_METHOD")
     public synchronized void registerLaunch(IBinder session, String url) {
         int outcome = NO_PREDICTION;
         long elapsedTimeMs = -1;
         SessionParams params = mSessionParams.get(session);
         if (params != null) {
             String predictedUrl = params.getPredictedUrl();
             outcome = predictedUrl == null ? NO_PREDICTION : predictedUrl.equals(url)
                             ? GOOD_PREDICTION
                             : BAD_PREDICTION;
             long now = SystemClock.elapsedRealtime();
             elapsedTimeMs = now - params.getLastMayLaunchUrlTimestamp();
             params.setPredictionMetrics(null, 0);
             if (outcome == GOOD_PREDICTION) {
                 RequestThrottler.getForUid(mContext, params.uid).registerSuccess(url);
             }
         }
         RecordHistogram.recordEnumeratedHistogram(
                 "CustomTabs.PredictionStatus", outcome, PREDICTION_STATUS_COUNT);
         if (outcome == GOOD_PREDICTION) {
             RecordHistogram.recordCustomTimesHistogram("CustomTabs.PredictionToLaunch",
                     elapsedTimeMs, 1, TimeUnit.MINUTES.toMillis(3), TimeUnit.MILLISECONDS, 100);
         }
+        RecordHistogram.recordEnumeratedHistogram(
+                "CustomTabs.WarmupStateOnLaunch", getWarmupState(session), SESSION_WARMUP_COUNT);
     }
 
     @SuppressFBWarnings("CHROMIUM_SYNCHRONIZED_METHOD")
     public synchronized Referrer getReferrerForSession(IBinder session) {
         SessionParams params = mSessionParams.get(session);
         return params != null ? params.referrer : null;
     }
 
     @SuppressFBWarnings("CHROMIUM_SYNCHRONIZED_METHOD")
     public synchronized ICustomTabsCallback getCallbackForSession(IBinder session) {
@@ skipping 66 matching lines @@
     public synchronized void cleanupAll() {
         List<IBinder> sessions = new ArrayList<>(mSessionParams.keySet());
         for (IBinder session : sessions) cleanupSession(session);
     }
 
     @SuppressFBWarnings("CHROMIUM_SYNCHRONIZED_METHOD")
     private synchronized void cleanupSession(IBinder session) {
         SessionParams params = mSessionParams.get(session);
         if (params == null) return;
         mSessionParams.remove(session);
+        mUidHasCalledWarmup.delete(params.uid);
         IBinder binder = params.callback.asBinder();
         binder.unlinkToDeath(params.deathRecipient, 0);
     }
 }