commit 9703eb291cd736ae5a119b1898436ba92fad5d6b
author markchien <markchien@google.com> Fri Jan 14 22:20:03 2022 +0800
committer markchien <markchien@google.com> Fri Jan 21 19:24:08 2022 +0800
tree 01dc7e1f029003441de279f0c6b2d3452e61df65
parent b45f4fb06d91cb9b4a84e8e39754430f231cec69

Replace INetd#trafficSwapActiveStatsMap with ConnectivityManager API

INetd#trafficSwapActiveStatsMap is deprecated and the implementaion is
moved into tethering (connectivity) mainline module. A new
ConnectivityManager API swapActiveStatsMap is temprary exposed for
NetworkStatsFactory. Once NetworkStatsFactory move into tethering
module, swapActiveStatsMap API would be removed and NetworkStatsFactory
should could call the implemeneted inside the module directly. This
should happen before T sdk finalization.

Bug: 209935649
Test: atest NetworkStatsFactoryTest
Change-Id: I6685fe513511e7af9fa6521601891c66d1297da0

service-t/src/com/android/server/net/NetworkStatsFactory.java

diff --git a/service-t/src/com/android/server/net/NetworkStatsFactory.java b/service-t/src/com/android/server/net/NetworkStatsFactory.java
index bb123a3..17f3455 100644
--- a/service-t/src/com/android/server/net/NetworkStatsFactory.java
+++ b/service-t/src/com/android/server/net/NetworkStatsFactory.java
@@ -26,10 +26,10 @@
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
-import android.net.INetd;
+import android.content.Context;
+import android.net.ConnectivityManager;
 import android.net.NetworkStats;
 import android.net.UnderlyingNetworkInfo;
-import android.os.RemoteException;
 import android.os.StrictMode;
 import android.os.SystemClock;
 
@@ -70,7 +70,7 @@
 
     private final boolean mUseBpfStats;
 
-    private final INetd mNetd;
+    private final Context mContext;
 
     /**
      * Guards persistent data access in this class
@@ -158,12 +158,12 @@
         NetworkStats.apply464xlatAdjustments(baseTraffic, stackedTraffic, mStackedIfaces);
     }
 
-    public NetworkStatsFactory(@NonNull INetd netd) {
-        this(new File("/proc/"), true, netd);
+    public NetworkStatsFactory(@NonNull Context ctx) {
+        this(ctx, new File("/proc/"), true);
     }
 
     @VisibleForTesting
-    public NetworkStatsFactory(File procRoot, boolean useBpfStats, @NonNull INetd netd) {
+    public NetworkStatsFactory(@NonNull Context ctx, File procRoot, boolean useBpfStats) {
         mStatsXtIfaceAll = new File(procRoot, "net/xt_qtaguid/iface_stat_all");
         mStatsXtIfaceFmt = new File(procRoot, "net/xt_qtaguid/iface_stat_fmt");
         mStatsXtUid = new File(procRoot, "net/xt_qtaguid/stats");
@@ -172,7 +172,7 @@
             mPersistSnapshot = new NetworkStats(SystemClock.elapsedRealtime(), -1);
             mTunAnd464xlatAdjustedStats = new NetworkStats(SystemClock.elapsedRealtime(), -1);
         }
-        mNetd = netd;
+        mContext = ctx;
     }
 
     public NetworkStats readBpfNetworkStatsDev() throws IOException {
@@ -295,11 +295,12 @@
     }
 
     @GuardedBy("mPersistentDataLock")
-    private void requestSwapActiveStatsMapLocked() throws RemoteException {
-        // Ask netd to do a active map stats swap. When the binder call successfully returns,
+    private void requestSwapActiveStatsMapLocked() {
+        // Do a active map stats swap. When the binder call successfully returns,
         // the system server should be able to safely read and clean the inactive map
         // without race problem.
-        mNetd.trafficSwapActiveStatsMap();
+        final ConnectivityManager cm = mContext.getSystemService(ConnectivityManager.class);
+        cm.swapActiveStatsMap();
     }
 
     /**
@@ -327,7 +328,7 @@
                 if (mUseBpfStats) {
                     try {
                         requestSwapActiveStatsMapLocked();
-                    } catch (RemoteException e) {
+                    } catch (RuntimeException e) {
                         throw new IOException(e);
                     }
                     // Stats are always read from the inactive map, so they must be read after the

service-t/src/com/android/server/net/NetworkStatsService.java

diff --git a/service-t/src/com/android/server/net/NetworkStatsService.java b/service-t/src/com/android/server/net/NetworkStatsService.java
index d0db938..815fc59 100644
--- a/service-t/src/com/android/server/net/NetworkStatsService.java
+++ b/service-t/src/com/android/server/net/NetworkStatsService.java
@@ -418,7 +418,7 @@
         final NetworkStatsService service = new NetworkStatsService(context,
                 INetd.Stub.asInterface((IBinder) context.getSystemService(Context.NETD_SERVICE)),
                 alarmManager, wakeLock, getDefaultClock(),
-                new DefaultNetworkStatsSettings(), new NetworkStatsFactory(netd),
+                new DefaultNetworkStatsSettings(), new NetworkStatsFactory(context),
                 new NetworkStatsObservers(), getDefaultSystemDir(), getDefaultBaseDir(),
                 new Dependencies());
 
@@ -987,8 +987,17 @@
         }
 
         // TODO: switch to data layer stats once kernel exports
-        // for now, read network layer stats and flatten across all ifaces
-        final NetworkStats networkLayer = readNetworkStatsUidDetail(uid, INTERFACES_ALL, TAG_ALL);
+        // for now, read network layer stats and flatten across all ifaces.
+        // This function is used to query NeworkStats for calle's uid. The only caller method
+        // TrafficStats#getDataLayerSnapshotForUid alrady claim no special permission to query
+        // its own NetworkStats.
+        final long ident = Binder.clearCallingIdentity();
+        final NetworkStats networkLayer;
+        try {
+            networkLayer = readNetworkStatsUidDetail(uid, INTERFACES_ALL, TAG_ALL);
+        } finally {
+            Binder.restoreCallingIdentity(ident);
+        }
 
         // splice in operation counts
         networkLayer.spliceOperationsFrom(mUidOperations);