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Merge changes from topic "vpn_data_accounting" into qt-dev

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am: b33d2ca2e3

Change-Id: I234eb2b20f47bde94b4aba89867e9d1c7e9ee7d5
This commit is contained in:
Varun Anand
2019-05-29 09:44:04 -07:00
committed by android-build-merger
parent 77d71f800f 81e79803de
commit 72f3140992
4 changed files with 312 additions and 133 deletions
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365
core/java/android/net/NetworkStats.java
View File

@@ -18,6 +18,7 @@ package android.net;
import static android.os.Process.CLAT_UID;
import android.annotation.NonNull;
import android.annotation.UnsupportedAppUsage;
import android.os.Parcel;
import android.os.Parcelable;
@@ -33,6 +34,7 @@ import libcore.util.EmptyArray;
import java.io.CharArrayWriter;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.function.Predicate;
import java.util.HashSet;
import java.util.Map;
import java.util.Objects;
@@ -993,23 +995,33 @@ public class NetworkStats implements Parcelable {
if (limitUid == UID_ALL && limitTag == TAG_ALL && limitIfaces == INTERFACES_ALL) {
return;
}
filter(e -> (limitUid == UID_ALL || limitUid == e.uid)
&& (limitTag == TAG_ALL || limitTag == e.tag)
&& (limitIfaces == INTERFACES_ALL
|| ArrayUtils.contains(limitIfaces, e.iface)));
}
/**
* Only keep entries with {@link #set} value less than {@link #SET_DEBUG_START}.
*
* <p>This mutates the original structure in place.
*/
public void filterDebugEntries() {
filter(e -> e.set < SET_DEBUG_START);
}
private void filter(Predicate<Entry> predicate) {
Entry entry = new Entry();
int nextOutputEntry = 0;
for (int i = 0; i < size; i++) {
entry = getValues(i, entry);
final boolean matches =
(limitUid == UID_ALL || limitUid == entry.uid)
&& (limitTag == TAG_ALL || limitTag == entry.tag)
&& (limitIfaces == INTERFACES_ALL
|| ArrayUtils.contains(limitIfaces, entry.iface));
if (matches) {
setValues(nextOutputEntry, entry);
if (predicate.test(entry)) {
if (nextOutputEntry != i) {
setValues(nextOutputEntry, entry);
}
nextOutputEntry++;
}
}
size = nextOutputEntry;
}
@@ -1175,133 +1187,221 @@ public class NetworkStats implements Parcelable {
/**
* VPN accounting. Move some VPN's underlying traffic to other UIDs that use tun0 iface.
*
* This method should only be called on delta NetworkStats. Do not call this method on a
* snapshot {@link NetworkStats} object because the tunUid and/or the underlyingIface may
* change over time.
* <p>This method should only be called on delta NetworkStats. Do not call this method on a
* snapshot {@link NetworkStats} object because the tunUid and/or the underlyingIface may change
* over time.
*
* This method performs adjustments for one active VPN package and one VPN iface at a time.
*
* It is possible for the VPN software to use multiple underlying networks. This method
* only migrates traffic for the primary underlying network.
* <p>This method performs adjustments for one active VPN package and one VPN iface at a time.
*
* @param tunUid uid of the VPN application
* @param tunIface iface of the vpn tunnel
* @param underlyingIface the primary underlying network iface used by the VPN application
* @return true if it successfully adjusts the accounting for VPN, false otherwise
* @param underlyingIfaces underlying network ifaces used by the VPN application
*/
public boolean migrateTun(int tunUid, String tunIface, String underlyingIface) {
Entry tunIfaceTotal = new Entry();
Entry underlyingIfaceTotal = new Entry();
public void migrateTun(int tunUid, @NonNull String tunIface,
@NonNull String[] underlyingIfaces) {
// Combined usage by all apps using VPN.
final Entry tunIfaceTotal = new Entry();
// Usage by VPN, grouped by its {@code underlyingIfaces}.
final Entry[] perInterfaceTotal = new Entry[underlyingIfaces.length];
// Usage by VPN, summed across all its {@code underlyingIfaces}.
final Entry underlyingIfacesTotal = new Entry();
tunAdjustmentInit(tunUid, tunIface, underlyingIface, tunIfaceTotal, underlyingIfaceTotal);
for (int i = 0; i < perInterfaceTotal.length; i++) {
perInterfaceTotal[i] = new Entry();
}
// If tunIface < underlyingIface, it leaves the overhead traffic in the VPN app.
// If tunIface > underlyingIface, the VPN app doesn't get credit for data compression.
tunAdjustmentInit(tunUid, tunIface, underlyingIfaces, tunIfaceTotal, perInterfaceTotal,
underlyingIfacesTotal);
// If tunIface < underlyingIfacesTotal, it leaves the overhead traffic in the VPN app.
// If tunIface > underlyingIfacesTotal, the VPN app doesn't get credit for data compression.
// Negative stats should be avoided.
Entry pool = tunGetPool(tunIfaceTotal, underlyingIfaceTotal);
if (pool.isEmpty()) {
return true;
}
Entry moved =
addTrafficToApplications(tunUid, tunIface, underlyingIface, tunIfaceTotal, pool);
deductTrafficFromVpnApp(tunUid, underlyingIface, moved);
if (!moved.isEmpty()) {
Slog.wtf(TAG, "Failed to deduct underlying network traffic from VPN package. Moved="
+ moved);
return false;
}
return true;
final Entry[] moved =
addTrafficToApplications(tunUid, tunIface, underlyingIfaces, tunIfaceTotal,
perInterfaceTotal, underlyingIfacesTotal);
deductTrafficFromVpnApp(tunUid, underlyingIfaces, moved);
}
/**
* Initializes the data used by the migrateTun() method.
*
* This is the first pass iteration which does the following work:
* (1) Adds up all the traffic through the tunUid's underlyingIface
* (both foreground and background).
* (2) Adds up all the traffic through tun0 excluding traffic from the vpn app itself.
* <p>This is the first pass iteration which does the following work:
*
* <ul>
* <li>Adds up all the traffic through the tunUid's underlyingIfaces (both foreground and
* background).
* <li>Adds up all the traffic through tun0 excluding traffic from the vpn app itself.
* </ul>
*
* @param tunUid uid of the VPN application
* @param tunIface iface of the vpn tunnel
* @param underlyingIfaces underlying network ifaces used by the VPN application
* @param tunIfaceTotal output parameter; combined data usage by all apps using VPN
* @param perInterfaceTotal output parameter; data usage by VPN app, grouped by its {@code
* underlyingIfaces}
* @param underlyingIfacesTotal output parameter; data usage by VPN, summed across all of its
* {@code underlyingIfaces}
*/
private void tunAdjustmentInit(int tunUid, String tunIface, String underlyingIface,
Entry tunIfaceTotal, Entry underlyingIfaceTotal) {
Entry recycle = new Entry();
private void tunAdjustmentInit(int tunUid, @NonNull String tunIface,
@NonNull String[] underlyingIfaces, @NonNull Entry tunIfaceTotal,
@NonNull Entry[] perInterfaceTotal, @NonNull Entry underlyingIfacesTotal) {
final Entry recycle = new Entry();
for (int i = 0; i < size; i++) {
getValues(i, recycle);
if (recycle.uid == UID_ALL) {
throw new IllegalStateException(
"Cannot adjust VPN accounting on an iface aggregated NetworkStats.");
} if (recycle.set == SET_DBG_VPN_IN || recycle.set == SET_DBG_VPN_OUT) {
}
if (recycle.set == SET_DBG_VPN_IN || recycle.set == SET_DBG_VPN_OUT) {
throw new IllegalStateException(
"Cannot adjust VPN accounting on a NetworkStats containing SET_DBG_VPN_*");
}
if (recycle.uid == tunUid && recycle.tag == TAG_NONE
&& Objects.equals(underlyingIface, recycle.iface)) {
underlyingIfaceTotal.add(recycle);
if (recycle.tag != TAG_NONE) {
// TODO(b/123666283): Take all tags for tunUid into account.
continue;
}
if (recycle.uid != tunUid && recycle.tag == TAG_NONE
&& Objects.equals(tunIface, recycle.iface)) {
if (recycle.uid == tunUid) {
// Add up traffic through tunUid's underlying interfaces.
for (int j = 0; j < underlyingIfaces.length; j++) {
if (Objects.equals(underlyingIfaces[j], recycle.iface)) {
perInterfaceTotal[j].add(recycle);
underlyingIfacesTotal.add(recycle);
break;
}
}
} else if (tunIface.equals(recycle.iface)) {
// Add up all tunIface traffic excluding traffic from the vpn app itself.
tunIfaceTotal.add(recycle);
}
}
}
private static Entry tunGetPool(Entry tunIfaceTotal, Entry underlyingIfaceTotal) {
Entry pool = new Entry();
pool.rxBytes = Math.min(tunIfaceTotal.rxBytes, underlyingIfaceTotal.rxBytes);
pool.rxPackets = Math.min(tunIfaceTotal.rxPackets, underlyingIfaceTotal.rxPackets);
pool.txBytes = Math.min(tunIfaceTotal.txBytes, underlyingIfaceTotal.txBytes);
pool.txPackets = Math.min(tunIfaceTotal.txPackets, underlyingIfaceTotal.txPackets);
pool.operations = Math.min(tunIfaceTotal.operations, underlyingIfaceTotal.operations);
return pool;
}
/**
* Distributes traffic across apps that are using given {@code tunIface}, and returns the total
* traffic that should be moved off of {@code tunUid} grouped by {@code underlyingIfaces}.
*
* @param tunUid uid of the VPN application
* @param tunIface iface of the vpn tunnel
* @param underlyingIfaces underlying network ifaces used by the VPN application
* @param tunIfaceTotal combined data usage across all apps using {@code tunIface}
* @param perInterfaceTotal data usage by VPN app, grouped by its {@code underlyingIfaces}
* @param underlyingIfacesTotal data usage by VPN, summed across all of its {@code
* underlyingIfaces}
*/
private Entry[] addTrafficToApplications(int tunUid, @NonNull String tunIface,
@NonNull String[] underlyingIfaces, @NonNull Entry tunIfaceTotal,
@NonNull Entry[] perInterfaceTotal, @NonNull Entry underlyingIfacesTotal) {
// Traffic that should be moved off of each underlying interface for tunUid (see
// deductTrafficFromVpnApp below).
final Entry[] moved = new Entry[underlyingIfaces.length];
for (int i = 0; i < underlyingIfaces.length; i++) {
moved[i] = new Entry();
}
private Entry addTrafficToApplications(int tunUid, String tunIface, String underlyingIface,
Entry tunIfaceTotal, Entry pool) {
Entry moved = new Entry();
Entry tmpEntry = new Entry();
tmpEntry.iface = underlyingIface;
for (int i = 0; i < size; i++) {
// the vpn app is excluded from the redistribution but all moved traffic will be
// deducted from the vpn app (see deductTrafficFromVpnApp below).
if (Objects.equals(iface[i], tunIface) && uid[i] != tunUid) {
if (tunIfaceTotal.rxBytes > 0) {
tmpEntry.rxBytes = pool.rxBytes * rxBytes[i] / tunIfaceTotal.rxBytes;
} else {
tmpEntry.rxBytes = 0;
}
if (tunIfaceTotal.rxPackets > 0) {
tmpEntry.rxPackets = pool.rxPackets * rxPackets[i] / tunIfaceTotal.rxPackets;
} else {
tmpEntry.rxPackets = 0;
}
if (tunIfaceTotal.txBytes > 0) {
tmpEntry.txBytes = pool.txBytes * txBytes[i] / tunIfaceTotal.txBytes;
} else {
tmpEntry.txBytes = 0;
}
if (tunIfaceTotal.txPackets > 0) {
tmpEntry.txPackets = pool.txPackets * txPackets[i] / tunIfaceTotal.txPackets;
} else {
tmpEntry.txPackets = 0;
}
if (tunIfaceTotal.operations > 0) {
tmpEntry.operations =
pool.operations * operations[i] / tunIfaceTotal.operations;
} else {
tmpEntry.operations = 0;
}
tmpEntry.uid = uid[i];
tmpEntry.tag = tag[i];
final Entry tmpEntry = new Entry();
final int origSize = size;
for (int i = 0; i < origSize; i++) {
if (!Objects.equals(iface[i], tunIface)) {
// Consider only entries that go onto the VPN interface.
continue;
}
if (uid[i] == tunUid) {
// Exclude VPN app from the redistribution, as it can choose to create packet
// streams by writing to itself.
continue;
}
tmpEntry.uid = uid[i];
tmpEntry.tag = tag[i];
tmpEntry.metered = metered[i];
tmpEntry.roaming = roaming[i];
tmpEntry.defaultNetwork = defaultNetwork[i];
// In a first pass, compute this entry's total share of data across all
// underlyingIfaces. This is computed on the basis of the share of this entry's usage
// over tunIface.
// TODO: Consider refactoring first pass into a separate helper method.
long totalRxBytes = 0;
if (tunIfaceTotal.rxBytes > 0) {
// Note - The multiplication below should not overflow since NetworkStatsService
// processes this every time device has transmitted/received amount equivalent to
// global threshold alert (~ 2MB) across all interfaces.
final long rxBytesAcrossUnderlyingIfaces =
underlyingIfacesTotal.rxBytes * rxBytes[i] / tunIfaceTotal.rxBytes;
// app must not be blamed for more than it consumed on tunIface
totalRxBytes = Math.min(rxBytes[i], rxBytesAcrossUnderlyingIfaces);
}
long totalRxPackets = 0;
if (tunIfaceTotal.rxPackets > 0) {
final long rxPacketsAcrossUnderlyingIfaces =
underlyingIfacesTotal.rxPackets * rxPackets[i] / tunIfaceTotal.rxPackets;
totalRxPackets = Math.min(rxPackets[i], rxPacketsAcrossUnderlyingIfaces);
}
long totalTxBytes = 0;
if (tunIfaceTotal.txBytes > 0) {
final long txBytesAcrossUnderlyingIfaces =
underlyingIfacesTotal.txBytes * txBytes[i] / tunIfaceTotal.txBytes;
totalTxBytes = Math.min(txBytes[i], txBytesAcrossUnderlyingIfaces);
}
long totalTxPackets = 0;
if (tunIfaceTotal.txPackets > 0) {
final long txPacketsAcrossUnderlyingIfaces =
underlyingIfacesTotal.txPackets * txPackets[i] / tunIfaceTotal.txPackets;
totalTxPackets = Math.min(txPackets[i], txPacketsAcrossUnderlyingIfaces);
}
long totalOperations = 0;
if (tunIfaceTotal.operations > 0) {
final long operationsAcrossUnderlyingIfaces =
underlyingIfacesTotal.operations * operations[i] / tunIfaceTotal.operations;
totalOperations = Math.min(operations[i], operationsAcrossUnderlyingIfaces);
}
// In a second pass, distribute these values across interfaces in the proportion that
// each interface represents of the total traffic of the underlying interfaces.
for (int j = 0; j < underlyingIfaces.length; j++) {
tmpEntry.iface = underlyingIfaces[j];
tmpEntry.rxBytes = 0;
// Reset 'set' to correct value since it gets updated when adding debug info below.
tmpEntry.set = set[i];
tmpEntry.metered = metered[i];
tmpEntry.roaming = roaming[i];
tmpEntry.defaultNetwork = defaultNetwork[i];
if (underlyingIfacesTotal.rxBytes > 0) {
tmpEntry.rxBytes =
totalRxBytes
* perInterfaceTotal[j].rxBytes
/ underlyingIfacesTotal.rxBytes;
}
tmpEntry.rxPackets = 0;
if (underlyingIfacesTotal.rxPackets > 0) {
tmpEntry.rxPackets =
totalRxPackets
* perInterfaceTotal[j].rxPackets
/ underlyingIfacesTotal.rxPackets;
}
tmpEntry.txBytes = 0;
if (underlyingIfacesTotal.txBytes > 0) {
tmpEntry.txBytes =
totalTxBytes
* perInterfaceTotal[j].txBytes
/ underlyingIfacesTotal.txBytes;
}
tmpEntry.txPackets = 0;
if (underlyingIfacesTotal.txPackets > 0) {
tmpEntry.txPackets =
totalTxPackets
* perInterfaceTotal[j].txPackets
/ underlyingIfacesTotal.txPackets;
}
tmpEntry.operations = 0;
if (underlyingIfacesTotal.operations > 0) {
tmpEntry.operations =
totalOperations
* perInterfaceTotal[j].operations
/ underlyingIfacesTotal.operations;
}
// tmpEntry now contains the migrated data of the i-th entry for the j-th underlying
// interface. Add that data usage to this object.
combineValues(tmpEntry);
if (tag[i] == TAG_NONE) {
moved.add(tmpEntry);
// Add the migrated data to moved so it is deducted from the VPN app later.
moved[j].add(tmpEntry);
// Add debug info
tmpEntry.set = SET_DBG_VPN_IN;
combineValues(tmpEntry);
@@ -1311,38 +1411,45 @@ public class NetworkStats implements Parcelable {
return moved;
}
private void deductTrafficFromVpnApp(int tunUid, String underlyingIface, Entry moved) {
// Add debug info
moved.uid = tunUid;
moved.set = SET_DBG_VPN_OUT;
moved.tag = TAG_NONE;
moved.iface = underlyingIface;
moved.metered = METERED_ALL;
moved.roaming = ROAMING_ALL;
moved.defaultNetwork = DEFAULT_NETWORK_ALL;
combineValues(moved);
private void deductTrafficFromVpnApp(
int tunUid,
@NonNull String[] underlyingIfaces,
@NonNull Entry[] moved) {
for (int i = 0; i < underlyingIfaces.length; i++) {
moved[i].uid = tunUid;
// Add debug info
moved[i].set = SET_DBG_VPN_OUT;
moved[i].tag = TAG_NONE;
moved[i].iface = underlyingIfaces[i];
moved[i].metered = METERED_ALL;
moved[i].roaming = ROAMING_ALL;
moved[i].defaultNetwork = DEFAULT_NETWORK_ALL;
combineValues(moved[i]);
// Caveat: if the vpn software uses tag, the total tagged traffic may be greater than
// the TAG_NONE traffic.
//
// Relies on the fact that the underlying traffic only has state ROAMING_NO and METERED_NO,
// which should be the case as it comes directly from the /proc file. We only blend in the
// roaming data after applying these adjustments, by checking the NetworkIdentity of the
// underlying iface.
int idxVpnBackground = findIndex(underlyingIface, tunUid, SET_DEFAULT, TAG_NONE,
METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
if (idxVpnBackground != -1) {
tunSubtract(idxVpnBackground, this, moved);
}
// Caveat: if the vpn software uses tag, the total tagged traffic may be greater than
// the TAG_NONE traffic.
//
// Relies on the fact that the underlying traffic only has state ROAMING_NO and
// METERED_NO, which should be the case as it comes directly from the /proc file.
// We only blend in the roaming data after applying these adjustments, by checking the
// NetworkIdentity of the underlying iface.
final int idxVpnBackground = findIndex(underlyingIfaces[i], tunUid, SET_DEFAULT,
TAG_NONE, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
if (idxVpnBackground != -1) {
// Note - tunSubtract also updates moved[i]; whatever traffic that's left is removed
// from foreground usage.
tunSubtract(idxVpnBackground, this, moved[i]);
}
int idxVpnForeground = findIndex(underlyingIface, tunUid, SET_FOREGROUND, TAG_NONE,
METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
if (idxVpnForeground != -1) {
tunSubtract(idxVpnForeground, this, moved);
final int idxVpnForeground = findIndex(underlyingIfaces[i], tunUid, SET_FOREGROUND,
TAG_NONE, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO);
if (idxVpnForeground != -1) {
tunSubtract(idxVpnForeground, this, moved[i]);
}
}
}
private static void tunSubtract(int i, NetworkStats left, Entry right) {
private static void tunSubtract(int i, @NonNull NetworkStats left, @NonNull Entry right) {
long rxBytes = Math.min(left.rxBytes[i], right.rxBytes);
left.rxBytes[i] -= rxBytes;
right.rxBytes -= rxBytes;

4
services/core/java/com/android/server/net/NetworkStatsFactory.java
View File

@@ -263,6 +263,10 @@ public class NetworkStatsFactory {
return stats;
}
/**
* @deprecated Use NetworkStatsService#getDetailedUidStats which also accounts for
* VPN traffic
*/
public NetworkStats readNetworkStatsDetail() throws IOException {
return readNetworkStatsDetail(UID_ALL, null, TAG_ALL, null);
}

6
services/core/java/com/android/server/net/NetworkStatsRecorder.java
View File

@@ -41,10 +41,10 @@ import com.android.internal.net.VpnInfo;
import com.android.internal.util.FileRotator;
import com.android.internal.util.IndentingPrintWriter;
import libcore.io.IoUtils;
import com.google.android.collect.Sets;
import libcore.io.IoUtils;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.File;
@@ -234,7 +234,7 @@ public class NetworkStatsRecorder {
if (vpnArray != null) {
for (VpnInfo info : vpnArray) {
delta.migrateTun(info.ownerUid, info.vpnIface, info.primaryUnderlyingIface);
delta.migrateTun(info.ownerUid, info.vpnIface, info.underlyingIfaces);
}
}

70
services/core/java/com/android/server/net/NetworkStatsService.java
View File

@@ -293,6 +293,22 @@ public class NetworkStatsService extends INetworkStatsService.Stub {
/** Data layer operation counters for splicing into other structures. */
private NetworkStats mUidOperations = new NetworkStats(0L, 10);
/**
* Snapshot containing most recent network stats for all UIDs across all interfaces and tags
* since boot.
*
* <p>Maintains migrated VPN stats which are result of performing TUN migration on {@link
* #mLastUidDetailSnapshot}.
*/
@GuardedBy("mStatsLock")
private NetworkStats mTunAdjustedStats;
/**
* Used by {@link #mTunAdjustedStats} to migrate VPN traffic over delta between this snapshot
* and latest snapshot.
*/
@GuardedBy("mStatsLock")
private NetworkStats mLastUidDetailSnapshot;
/** Must be set in factory by calling #setHandler. */
private Handler mHandler;
private Handler.Callback mHandlerCallback;
@@ -812,15 +828,39 @@ public class NetworkStatsService extends INetworkStatsService.Stub {
@Override
public NetworkStats getDetailedUidStats(String[] requiredIfaces) {
try {
// Get the latest snapshot from NetworkStatsFactory.
// TODO: Querying for INTERFACES_ALL may incur performance penalty. Consider restricting
// this to limited set of ifaces.
NetworkStats uidDetailStats = getNetworkStatsUidDetail(INTERFACES_ALL);
// Migrate traffic from VPN UID over delta and update mTunAdjustedStats.
NetworkStats result;
synchronized (mStatsLock) {
migrateTunTraffic(uidDetailStats, mVpnInfos);
result = mTunAdjustedStats.clone();
}
// Apply filter based on ifacesToQuery.
final String[] ifacesToQuery =
NetworkStatsFactory.augmentWithStackedInterfaces(requiredIfaces);
return getNetworkStatsUidDetail(ifacesToQuery);
result.filter(UID_ALL, ifacesToQuery, TAG_ALL);
return result;
} catch (RemoteException e) {
Log.wtf(TAG, "Error compiling UID stats", e);
return new NetworkStats(0L, 0);
}
}
@VisibleForTesting
NetworkStats getTunAdjustedStats() {
synchronized (mStatsLock) {
if (mTunAdjustedStats == null) {
return null;
}
return mTunAdjustedStats.clone();
}
}
@Override
public String[] getMobileIfaces() {
return mMobileIfaces;
@@ -1295,6 +1335,34 @@ public class NetworkStatsService extends INetworkStatsService.Stub {
// a race condition between the service handler thread and the observer's
mStatsObservers.updateStats(xtSnapshot, uidSnapshot, new ArrayMap<>(mActiveIfaces),
new ArrayMap<>(mActiveUidIfaces), vpnArray, currentTime);
migrateTunTraffic(uidSnapshot, vpnArray);
}
/**
* Updates {@link #mTunAdjustedStats} with the delta containing traffic migrated off of VPNs.
*/
@GuardedBy("mStatsLock")
private void migrateTunTraffic(NetworkStats uidDetailStats, VpnInfo[] vpnInfoArray) {
if (mTunAdjustedStats == null) {
// Either device booted or system server restarted, hence traffic cannot be migrated
// correctly without knowing the past state of VPN's underlying networks.
mTunAdjustedStats = uidDetailStats;
mLastUidDetailSnapshot = uidDetailStats;
return;
}
// Migrate delta traffic from VPN to other apps.
NetworkStats delta = uidDetailStats.subtract(mLastUidDetailSnapshot);
for (VpnInfo info : vpnInfoArray) {
delta.migrateTun(info.ownerUid, info.vpnIface, info.underlyingIfaces);
}
// Filter out debug entries as that may lead to over counting.
delta.filterDebugEntries();
// Update #mTunAdjustedStats with migrated delta.
mTunAdjustedStats.combineAllValues(delta);
mTunAdjustedStats.setElapsedRealtime(uidDetailStats.getElapsedRealtime());
// Update last snapshot.
mLastUidDetailSnapshot = uidDetailStats;
}
/**