diff --git a/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java b/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java index 8ef6d6fc1f..eafa3eae4c 100644 --- a/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java +++ b/Tethering/apishim/30/com/android/networkstack/tethering/apishim/api30/BpfCoordinatorShimImpl.java @@ -116,6 +116,21 @@ public class BpfCoordinatorShimImpl return tetherStatsList; } + @Override + @Nullable + public TetherStatsValue tetherOffloadGetAndClearStats(int ifIndex) { + try { + final TetherStatsParcel stats = + mNetd.tetherOffloadGetAndClearStats(ifIndex); + return new TetherStatsValue(stats.rxPackets, stats.rxBytes, 0 /* rxErrors */, + stats.txPackets, stats.txBytes, 0 /* txErrors */); + } catch (RemoteException | ServiceSpecificException e) { + mLog.e("Exception when cleanup tether stats for upstream index " + + ifIndex + ": ", e); + return null; + } + } + @Override public String toString() { return "Netd used"; diff --git a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java index f94b5a946c..4ebf9144f2 100644 --- a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java +++ b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java @@ -20,6 +20,7 @@ import static android.net.netstats.provider.NetworkStatsProvider.QUOTA_UNLIMITED import android.net.util.SharedLog; import android.system.ErrnoException; +import android.system.Os; import android.system.OsConstants; import android.util.SparseArray; @@ -36,6 +37,8 @@ import com.android.networkstack.tethering.TetherLimitValue; import com.android.networkstack.tethering.TetherStatsKey; import com.android.networkstack.tethering.TetherStatsValue; +import java.io.FileDescriptor; + /** * Bpf coordinator class for API shims. */ @@ -43,6 +46,11 @@ public class BpfCoordinatorShimImpl extends com.android.networkstack.tethering.apishim.common.BpfCoordinatorShim { private static final String TAG = "api31.BpfCoordinatorShimImpl"; + // AF_KEY socket type. See include/linux/socket.h. + private static final int AF_KEY = 15; + // PFKEYv2 constants. See include/uapi/linux/pfkeyv2.h. + private static final int PF_KEY_V2 = 2; + @NonNull private final SharedLog mLog; @@ -177,6 +185,53 @@ public class BpfCoordinatorShimImpl return true; } + @Override + @Nullable + public TetherStatsValue tetherOffloadGetAndClearStats(int ifIndex) { + if (!isInitialized()) return null; + + // getAndClearTetherOffloadStats is called after all offload rules have already been + // deleted for the given upstream interface. Before starting to do cleanup stuff in this + // function, use synchronizeKernelRCU to make sure that all the current running eBPF + // programs are finished on all CPUs, especially the unfinished packet processing. After + // synchronizeKernelRCU returned, we can safely read or delete on the stats map or the + // limit map. + final int res = synchronizeKernelRCU(); + if (res != 0) { + // Error log but don't return. Do as much cleanup as possible. + mLog.e("synchronize_rcu() failed: " + res); + } + + TetherStatsValue statsValue = null; + try { + statsValue = mBpfStatsMap.getValue(new TetherStatsKey(ifIndex)); + } catch (ErrnoException e) { + mLog.e("Could not get stats entry for interface index " + ifIndex + ": ", e); + return null; + } + + if (statsValue == null) { + mLog.e("Could not get stats entry for interface index " + ifIndex); + return null; + } + + try { + mBpfStatsMap.deleteEntry(new TetherStatsKey(ifIndex)); + } catch (ErrnoException e) { + mLog.e("Could not delete stats entry for interface index " + ifIndex + ": ", e); + return null; + } + + try { + mBpfLimitMap.deleteEntry(new TetherLimitKey(ifIndex)); + } catch (ErrnoException e) { + mLog.e("Could not delete limit for interface index " + ifIndex + ": ", e); + return null; + } + + return statsValue; + } + @Override public String toString() { return "mBpfIngressMap{" @@ -187,4 +242,36 @@ public class BpfCoordinatorShimImpl + (mBpfLimitMap != null ? "initialized" : "not initialized") + "} " + "}"; } + + /** + * Call synchronize_rcu() to block until all existing RCU read-side critical sections have + * been completed. + * Note that BpfCoordinatorTest have no permissions to create or close pf_key socket. It is + * okay for now because the caller #bpfGetAndClearStats doesn't care the result of this + * function. The tests don't be broken. + * TODO: Wrap this function into Dependencies for mocking in tests. + */ + private int synchronizeKernelRCU() { + // This is a temporary hack for network stats map swap on devices running + // 4.9 kernels. The kernel code of socket release on pf_key socket will + // explicitly call synchronize_rcu() which is exactly what we need. + FileDescriptor pfSocket; + try { + pfSocket = Os.socket(AF_KEY, OsConstants.SOCK_RAW | OsConstants.SOCK_CLOEXEC, + PF_KEY_V2); + } catch (ErrnoException e) { + mLog.e("create PF_KEY socket failed: ", e); + return e.errno; + } + + // When closing socket, synchronize_rcu() gets called in sock_release(). + try { + Os.close(pfSocket); + } catch (ErrnoException e) { + mLog.e("failed to close the PF_KEY socket: ", e); + return e.errno; + } + + return 0; + } } diff --git a/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java b/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java index de65ea5799..61abfa3aaa 100644 --- a/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java +++ b/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java @@ -89,5 +89,24 @@ public abstract class BpfCoordinatorShim { */ @Nullable public abstract boolean tetherOffloadSetInterfaceQuota(int ifIndex, long quotaBytes); + + /** + * Return BPF tethering offload statistics and clear the stats for a given upstream. + * + * Must only be called once all offload rules have already been deleted for the given upstream + * interface. The existing stats will be fetched and returned. The stats and the limit for the + * given upstream interface will be deleted as well. + * + * The stats and limit for a given upstream interface must be initialized (using + * tetherOffloadSetInterfaceQuota) before any offload will occur on that interface. + * + * Note that this can be only called while the BPF maps were initialized. + * + * @param ifIndex Index of upstream interface. + * @return TetherStatsValue, which contains the given upstream interface's tethering statistics + * since tethering was first started on that upstream interface. + */ + @Nullable + public abstract TetherStatsValue tetherOffloadGetAndClearStats(int ifIndex); } diff --git a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java index d5ab55061c..64ac37ce03 100644 --- a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java +++ b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java @@ -34,15 +34,12 @@ import android.net.MacAddress; import android.net.NetworkStats; import android.net.NetworkStats.Entry; import android.net.TetherOffloadRuleParcel; -import android.net.TetherStatsParcel; import android.net.ip.IpServer; import android.net.netstats.provider.NetworkStatsProvider; import android.net.util.SharedLog; import android.net.util.TetheringUtils.ForwardedStats; import android.os.ConditionVariable; import android.os.Handler; -import android.os.RemoteException; -import android.os.ServiceSpecificException; import android.system.ErrnoException; import android.text.TextUtils; import android.util.Log; @@ -361,22 +358,19 @@ public class BpfCoordinator { // Do cleanup functionality if there is no more rule on the given upstream. final int upstreamIfindex = rule.upstreamIfindex; if (!isAnyRuleOnUpstream(upstreamIfindex)) { - try { - final TetherStatsParcel stats = - mNetd.tetherOffloadGetAndClearStats(upstreamIfindex); - SparseArray tetherStatsList = - new SparseArray(); - tetherStatsList.put(stats.ifIndex, new TetherStatsValue(stats.rxPackets, - stats.rxBytes, 0 /* rxErrors */, stats.txPackets, stats.txBytes, - 0 /* txErrors */)); - - // Update the last stats delta and delete the local cache for a given upstream. - updateQuotaAndStatsFromSnapshot(tetherStatsList); - mStats.remove(upstreamIfindex); - } catch (RemoteException | ServiceSpecificException e) { - Log.wtf(TAG, "Exception when cleanup tether stats for upstream index " - + upstreamIfindex + ": ", e); + final TetherStatsValue statsValue = + mBpfCoordinatorShim.tetherOffloadGetAndClearStats(upstreamIfindex); + if (statsValue == null) { + Log.wtf(TAG, "Fail to cleanup tether stats for upstream index " + upstreamIfindex); + return; } + + SparseArray tetherStatsList = new SparseArray(); + tetherStatsList.put(upstreamIfindex, statsValue); + + // Update the last stats delta and delete the local cache for a given upstream. + updateQuotaAndStatsFromSnapshot(tetherStatsList); + mStats.remove(upstreamIfindex); } } diff --git a/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java b/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java index 183571f266..4abaf03f25 100644 --- a/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java +++ b/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java @@ -137,6 +137,11 @@ public class BpfCoordinatorTest { mMap.put(key, value); } + @Override + public boolean deleteEntry(Struct key) throws ErrnoException { + return mMap.remove(key) != null; + } + @Override public V getValue(@NonNull K key) throws ErrnoException { // Return value for a given key. Otherwise, return null without an error ENOENT. @@ -253,12 +258,16 @@ public class BpfCoordinatorTest { } // Update a stats entry or create if not exists. + private void updateStatsEntryToStatsMap(@NonNull TetherStatsParcel stats) throws Exception { + final TetherStatsKey key = new TetherStatsKey(stats.ifIndex); + final TetherStatsValue value = new TetherStatsValue(stats.rxPackets, stats.rxBytes, + 0L /* rxErrors */, stats.txPackets, stats.txBytes, 0L /* txErrors */); + mBpfStatsMap.updateEntry(key, value); + } + private void updateStatsEntry(@NonNull TetherStatsParcel stats) throws Exception { if (mDeps.isAtLeastS()) { - final TetherStatsKey key = new TetherStatsKey(stats.ifIndex); - final TetherStatsValue value = new TetherStatsValue(stats.rxPackets, stats.rxBytes, - 0L /* rxErrors */, stats.txPackets, stats.txBytes, 0L /* txErrors */); - mBpfStatsMap.updateEntry(key, value); + updateStatsEntryToStatsMap(stats); } else { when(mNetd.tetherOffloadGetStats()).thenReturn(new TetherStatsParcel[] {stats}); } @@ -282,6 +291,21 @@ public class BpfCoordinatorTest { waitForIdle(); } + // In tests, the stats need to be set before deleting the last rule. + // The reason is that BpfCoordinator#tetherOffloadRuleRemove reads the stats + // of the deleting interface after the last rule deleted. #tetherOffloadRuleRemove + // does the interface cleanup failed if there is no stats for the deleting interface. + // Note that the mocked tetherOffloadGetAndClearStats of netd replaces all stats entries + // because it doesn't store the previous entries. + private void updateStatsEntryForTetherOffloadGetAndClearStats(TetherStatsParcel stats) + throws Exception { + if (mDeps.isAtLeastS()) { + updateStatsEntryToStatsMap(stats); + } else { + when(mNetd.tetherOffloadGetAndClearStats(stats.ifIndex)).thenReturn(stats); + } + } + private void clearStatsInvocations() { if (mDeps.isAtLeastS()) { clearInvocations(mBpfStatsMap); @@ -377,6 +401,17 @@ public class BpfCoordinatorTest { } } + private void verifyTetherOffloadGetAndClearStats(@Nullable InOrder inOrder, int ifIndex) + throws Exception { + if (mDeps.isAtLeastS()) { + inOrder.verify(mBpfStatsMap).getValue(new TetherStatsKey(ifIndex)); + inOrder.verify(mBpfStatsMap).deleteEntry(new TetherStatsKey(ifIndex)); + inOrder.verify(mBpfLimitMap).deleteEntry(new TetherLimitKey(ifIndex)); + } else { + inOrder.verify(mNetd).tetherOffloadGetAndClearStats(ifIndex); + } + } + // S+ and R api minimum tests. // The following tests are used to provide minimum checking for the APIs on different flow. // The auto merge is not enabled on mainline prod. The code flow R may be verified at the @@ -396,17 +431,23 @@ public class BpfCoordinatorTest { final Integer mobileIfIndex = 100; coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface); + // InOrder is required because mBpfStatsMap may be accessed by both + // BpfCoordinator#tetherOffloadRuleAdd and BpfCoordinator#tetherOffloadGetAndClearStats. + // The #verifyTetherOffloadGetAndClearStats can't distinguish who has ever called + // mBpfStatsMap#getValue and get a wrong calling count which counts all. + final InOrder inOrder = inOrder(mNetd, mBpfIngressMap, mBpfLimitMap, mBpfStatsMap); final Ipv6ForwardingRule rule = buildTestForwardingRule(mobileIfIndex, NEIGH_A, MAC_A); coordinator.tetherOffloadRuleAdd(mIpServer, rule); - verifyTetherOffloadRuleAdd(null, rule); - verifyTetherOffloadSetInterfaceQuota(null, mobileIfIndex, QUOTA_UNLIMITED, + verifyTetherOffloadRuleAdd(inOrder, rule); + verifyTetherOffloadSetInterfaceQuota(inOrder, mobileIfIndex, QUOTA_UNLIMITED, true /* isInit */); // Removing the last rule on current upstream immediately sends the cleanup stuff to netd. - when(mNetd.tetherOffloadGetAndClearStats(mobileIfIndex)) - .thenReturn(buildTestTetherStatsParcel(mobileIfIndex, 0, 0, 0, 0)); + updateStatsEntryForTetherOffloadGetAndClearStats( + buildTestTetherStatsParcel(mobileIfIndex, 0, 0, 0, 0)); coordinator.tetherOffloadRuleRemove(mIpServer, rule); - verifyTetherOffloadRuleRemove(null, rule); + verifyTetherOffloadRuleRemove(inOrder, rule); + verifyTetherOffloadGetAndClearStats(inOrder, mobileIfIndex); } // TODO: remove once presubmit tests on R even the code is submitted on S. @@ -717,11 +758,11 @@ public class BpfCoordinatorTest { verifyNeverTetherOffloadSetInterfaceQuota(inOrder); // Removing the last rule on current upstream immediately sends the cleanup stuff to netd. - when(mNetd.tetherOffloadGetAndClearStats(mobileIfIndex)) - .thenReturn(buildTestTetherStatsParcel(mobileIfIndex, 0, 0, 0, 0)); + updateStatsEntryForTetherOffloadGetAndClearStats( + buildTestTetherStatsParcel(mobileIfIndex, 0, 0, 0, 0)); coordinator.tetherOffloadRuleRemove(mIpServer, ruleA); verifyTetherOffloadRuleRemove(inOrder, ruleA); - inOrder.verify(mNetd).tetherOffloadGetAndClearStats(mobileIfIndex); + verifyTetherOffloadGetAndClearStats(inOrder, mobileIfIndex); inOrder.verifyNoMoreInteractions(); } @@ -767,8 +808,8 @@ public class BpfCoordinatorTest { mobileIfIndex, NEIGH_A, MAC_A); final Ipv6ForwardingRule mobileRuleB = buildTestForwardingRule( mobileIfIndex, NEIGH_B, MAC_B); - when(mNetd.tetherOffloadGetAndClearStats(ethIfIndex)) - .thenReturn(buildTestTetherStatsParcel(ethIfIndex, 10, 20, 30, 40)); + updateStatsEntryForTetherOffloadGetAndClearStats( + buildTestTetherStatsParcel(ethIfIndex, 10, 20, 30, 40)); // Update the existing rules for upstream changes. The rules are removed and re-added one // by one for updating upstream interface index by #tetherOffloadRuleUpdate. @@ -778,16 +819,16 @@ public class BpfCoordinatorTest { verifyTetherOffloadSetInterfaceQuota(inOrder, mobileIfIndex, QUOTA_UNLIMITED, true /* isInit */); verifyTetherOffloadRuleRemove(inOrder, ethernetRuleB); - inOrder.verify(mNetd).tetherOffloadGetAndClearStats(ethIfIndex); + verifyTetherOffloadGetAndClearStats(inOrder, ethIfIndex); verifyTetherOffloadRuleAdd(inOrder, mobileRuleB); // [3] Clear all rules for a given IpServer. - when(mNetd.tetherOffloadGetAndClearStats(mobileIfIndex)) - .thenReturn(buildTestTetherStatsParcel(mobileIfIndex, 50, 60, 70, 80)); + updateStatsEntryForTetherOffloadGetAndClearStats( + buildTestTetherStatsParcel(mobileIfIndex, 50, 60, 70, 80)); coordinator.tetherOffloadRuleClear(mIpServer); verifyTetherOffloadRuleRemove(inOrder, mobileRuleA); verifyTetherOffloadRuleRemove(inOrder, mobileRuleB); - inOrder.verify(mNetd).tetherOffloadGetAndClearStats(mobileIfIndex); + verifyTetherOffloadGetAndClearStats(inOrder, mobileIfIndex); // [4] Force pushing stats update to verify that the last diff of stats is reported on all // upstreams.