Wifi usability: Data stall detection based on link layer stats

This is an effort to define new criterion for triggering Wifi data stall:
(1) Defined data stall criterion based on transmit and/or receive throughput, transmit packet error rate, and CCA level. Data stall is triggered when transmit and/or receive links are consecutively bad over multiple RSSI polls.
(2) Added DeviceConfig flags (that is disabled by default) which may be configured on the server side to tune the thresholds at which data stall gets triggered.

Bug: 141027476

Test: frameworks/opt/net/wifi/tests/wifitests/runtests.sh

Change-Id: I3c5d9756ff74c0b5682a0b2a51ed64c27c679d72
Signed-off-by: Mingguang Xu <mingguangxu@google.com>
Merged-In: I76d6338cd2d482d198fde1e5a2d1a0540c087ca6

2 files changed, 118 insertions, 54 deletions

diff --git a/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java b/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java
index a26582c5c..7896a8f0b 100644
--- a/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/ClientModeImplTest.java
@@ -3340,7 +3340,7 @@ public class ClientModeImplTest {
         when(mWifiNative.getWifiLinkLayerStats(any())).thenReturn(newLLStats);
         mCmi.sendMessage(ClientModeImpl.CMD_RSSI_POLL, 1);
         mLooper.dispatchAll();
-        verify(mWifiDataStall).checkForDataStall(oldLLStats, newLLStats);
+        verify(mWifiDataStall).checkForDataStall(oldLLStats, newLLStats, mCmi.getWifiInfo());
         verify(mWifiMetrics).incrementWifiLinkLayerUsageStats(newLLStats);
     }
 
@@ -3356,7 +3356,7 @@ public class ClientModeImplTest {
 
         WifiLinkLayerStats stats = new WifiLinkLayerStats();
         when(mWifiNative.getWifiLinkLayerStats(any())).thenReturn(stats);
-        when(mWifiDataStall.checkForDataStall(any(), any()))
+        when(mWifiDataStall.checkForDataStall(any(), any(), any()))
                 .thenReturn(WifiIsUnusableEvent.TYPE_UNKNOWN);
         mCmi.sendMessage(ClientModeImpl.CMD_RSSI_POLL, 1);
         mLooper.dispatchAll();
@@ -3364,11 +3364,16 @@ public class ClientModeImplTest {
         verify(mWifiMetrics, never()).addToWifiUsabilityStatsList(WifiUsabilityStats.LABEL_BAD,
                 eq(anyInt()), eq(-1));
 
-        when(mWifiDataStall.checkForDataStall(any(), any()))
+        when(mWifiDataStall.checkForDataStall(any(), any(), any()))
                 .thenReturn(WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX);
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(10L);
         mCmi.sendMessage(ClientModeImpl.CMD_RSSI_POLL, 1);
         mLooper.dispatchAll();
         verify(mWifiMetrics, times(2)).updateWifiUsabilityStatsEntries(any(), eq(stats));
+        when(mClock.getElapsedSinceBootMillis())
+                .thenReturn(10L + ClientModeImpl.DURATION_TO_WAIT_ADD_STATS_AFTER_DATA_STALL_MS);
+        mCmi.sendMessage(ClientModeImpl.CMD_RSSI_POLL, 1);
+        mLooper.dispatchAll();
         verify(mWifiMetrics).addToWifiUsabilityStatsList(WifiUsabilityStats.LABEL_BAD,
                 WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX, -1);
     }
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiDataStallTest.java b/tests/wifitests/src/com/android/server/wifi/WifiDataStallTest.java
index a5f6852f8..71b658923 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiDataStallTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiDataStallTest.java
@@ -17,14 +17,17 @@
 package com.android.server.wifi;
 
 import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.anyInt;
 import static org.mockito.Mockito.anyLong;
 import static org.mockito.Mockito.never;
-import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.Context;
+import android.net.wifi.WifiInfo;
+import android.os.Looper;
+import android.provider.DeviceConfig.OnPropertiesChangedListener;
 import android.provider.Settings;
 
 import androidx.test.filters.SmallTest;
@@ -33,6 +36,7 @@ import com.android.server.wifi.nano.WifiMetricsProto.WifiIsUnusableEvent;
 
 import org.junit.Before;
 import org.junit.Test;
+import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
@@ -46,9 +50,15 @@ public class WifiDataStallTest {
     @Mock FrameworkFacade mFacade;
     @Mock WifiMetrics mWifiMetrics;
     WifiDataStall mWifiDataStall;
+    @Mock Clock mClock;
+    @Mock DeviceConfigFacade mDeviceConfigFacade;
+    @Mock Looper mClientModeImplLooper;
+    @Mock WifiInfo mWifiInfo;
 
     private final WifiLinkLayerStats mOldLlStats = new WifiLinkLayerStats();
     private final WifiLinkLayerStats mNewLlStats = new WifiLinkLayerStats();
+    final ArgumentCaptor<OnPropertiesChangedListener> mOnPropertiesChangedListenerCaptor =
+            ArgumentCaptor.forClass(OnPropertiesChangedListener.class);
 
     /**
      * Sets up for unit test
@@ -64,21 +74,38 @@ public class WifiDataStallTest {
                 Settings.Global.WIFI_DATA_STALL_MIN_TX_SUCCESS_WITHOUT_RX,
                 WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT))
                 .thenReturn(WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT);
+        when(mDeviceConfigFacade.getDataStallDurationMs()).thenReturn(
+                DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS);
+        when(mDeviceConfigFacade.getDataStallTxTputThrMbps()).thenReturn(
+                DeviceConfigFacade.DEFAULT_DATA_STALL_TX_TPUT_THR_MBPS);
+        when(mDeviceConfigFacade.getDataStallRxTputThrMbps()).thenReturn(
+                DeviceConfigFacade.DEFAULT_DATA_STALL_RX_TPUT_THR_MBPS);
+        when(mDeviceConfigFacade.getDataStallTxPerThr()).thenReturn(
+                DeviceConfigFacade.DEFAULT_DATA_STALL_TX_PER_THR);
+        when(mDeviceConfigFacade.getDataStallCcaLevelThr()).thenReturn(
+                DeviceConfigFacade.DEFAULT_DATA_STALL_CCA_LEVEL_THR);
+        when(mWifiInfo.getLinkSpeed()).thenReturn(100);
+        when(mWifiInfo.getRxLinkSpeedMbps()).thenReturn(100);
+        when(mWifiInfo.getFrequency()).thenReturn(5850);
+        when(mWifiInfo.getBSSID()).thenReturn("5G_WiFi");
 
-        mWifiDataStall = new WifiDataStall(mContext, mFacade, mWifiMetrics);
+        mWifiDataStall = new WifiDataStall(mContext, mFacade, mWifiMetrics, mDeviceConfigFacade,
+                mClientModeImplLooper, mClock);
 
         mOldLlStats.txmpdu_be = 1000;
-        mOldLlStats.retries_be = 2000;
+        mOldLlStats.retries_be = 1000;
         mOldLlStats.lostmpdu_be = 3000;
         mOldLlStats.rxmpdu_be = 4000;
         mOldLlStats.timeStampInMs = 10000;
 
-        mNewLlStats.txmpdu_be = mOldLlStats.txmpdu_be;
-        mNewLlStats.retries_be = mOldLlStats.retries_be;
+        mNewLlStats.txmpdu_be = 2 * mOldLlStats.txmpdu_be;
+        mNewLlStats.retries_be = 10 * mOldLlStats.retries_be;
         mNewLlStats.lostmpdu_be = mOldLlStats.lostmpdu_be;
         mNewLlStats.rxmpdu_be = mOldLlStats.rxmpdu_be;
         mNewLlStats.timeStampInMs = mOldLlStats.timeStampInMs
                 + WifiDataStall.MAX_MS_DELTA_FOR_DATA_STALL - 1;
+        verify(mDeviceConfigFacade).addOnPropertiesChangedListener(any(),
+                mOnPropertiesChangedListenerCaptor.capture());
     }
 
     /**
@@ -98,23 +125,53 @@ public class WifiDataStallTest {
      */
     @Test
     public void verifyDataStallTxFailure() throws Exception {
-        mNewLlStats.lostmpdu_be = mOldLlStats.lostmpdu_be + WifiDataStall.MIN_TX_BAD_DEFAULT;
-        assertEquals(WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(10L);
+
+        assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verifyUpdateWifiIsUnusableLinkLayerStats();
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(
+                10L + DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS);
+        assertEquals(WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verify(mWifiMetrics).logWifiIsUnusableEvent(WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX);
     }
 
     /**
+     * Verify there is no data stall from tx failures if tx failures are not consecutively bad
+     */
+    @Test
+    public void verifyNoDataStallWhenTxFailureIsNotConsecutive() throws Exception {
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(10L);
+
+        assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
+        verifyUpdateWifiIsUnusableLinkLayerStats();
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(
+                10L + DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS);
+        mNewLlStats.retries_be = 2 * mOldLlStats.retries_be;
+        assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
+        verify(mWifiMetrics, never()).logWifiIsUnusableEvent(
+                WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX);
+    }
+
+    /**
      * Verify there is data stall from rx failures
      */
     @Test
     public void verifyDataStallRxFailure() throws Exception {
-        mNewLlStats.txmpdu_be =
-                mOldLlStats.txmpdu_be + WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT;
-        assertEquals(WifiIsUnusableEvent.TYPE_DATA_STALL_TX_WITHOUT_RX,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+        when(mWifiInfo.getRxLinkSpeedMbps()).thenReturn(1);
+        mNewLlStats.retries_be = 2 * mOldLlStats.retries_be;
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(10L);
+
+        assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verifyUpdateWifiIsUnusableLinkLayerStats();
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(
+                10L + DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS);
+        assertEquals(WifiIsUnusableEvent.TYPE_DATA_STALL_TX_WITHOUT_RX,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verify(mWifiMetrics).logWifiIsUnusableEvent(
                 WifiIsUnusableEvent.TYPE_DATA_STALL_TX_WITHOUT_RX);
     }
@@ -124,58 +181,61 @@ public class WifiDataStallTest {
      */
     @Test
     public void verifyDataStallBothTxRxFailure() throws Exception {
-        mNewLlStats.lostmpdu_be = mOldLlStats.lostmpdu_be + WifiDataStall.MIN_TX_BAD_DEFAULT;
-        mNewLlStats.txmpdu_be =
-                mOldLlStats.txmpdu_be + WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT;
-        assertEquals(WifiIsUnusableEvent.TYPE_DATA_STALL_BOTH,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+        when(mWifiInfo.getRxLinkSpeedMbps()).thenReturn(1);
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(10L);
+
+        assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verifyUpdateWifiIsUnusableLinkLayerStats();
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(
+                10L + DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS);
+        assertEquals(WifiIsUnusableEvent.TYPE_DATA_STALL_BOTH,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verify(mWifiMetrics).logWifiIsUnusableEvent(WifiIsUnusableEvent.TYPE_DATA_STALL_BOTH);
     }
 
     /**
-     * Verify that we can change the minimum number of tx failures
-     * to trigger data stall from settings
+     * Verify that we can change the duration of evaluating Wifi conditions
+     * to trigger data stall from DeviceConfigFacade
      */
     @Test
-    public void verifyDataStallTxFailureSettingsChange() throws Exception {
-        when(mFacade.getIntegerSetting(mContext,
-                Settings.Global.WIFI_DATA_STALL_MIN_TX_BAD,
-                WifiDataStall.MIN_TX_BAD_DEFAULT))
-                .thenReturn(WifiDataStall.MIN_TX_BAD_DEFAULT + 1);
-        mWifiDataStall.loadSettings();
-        verify(mWifiMetrics).setWifiDataStallMinTxBad(WifiDataStall.MIN_TX_BAD_DEFAULT + 1);
-        verify(mWifiMetrics, times(2)).setWifiDataStallMinRxWithoutTx(
-                WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT);
+    public void verifyDataStallDurationDeviceConfigChange() throws Exception {
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(10L);
+        when(mDeviceConfigFacade.getDataStallDurationMs()).thenReturn(
+                DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS + 1);
+        mOnPropertiesChangedListenerCaptor.getValue().onPropertiesChanged(null);
 
-        mNewLlStats.lostmpdu_be = mOldLlStats.lostmpdu_be + WifiDataStall.MIN_TX_BAD_DEFAULT;
         assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verifyUpdateWifiIsUnusableLinkLayerStats();
-        verify(mWifiMetrics, never()).logWifiIsUnusableEvent(anyInt());
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(
+                10L + DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS);
+        assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
+        verify(mWifiMetrics, never()).logWifiIsUnusableEvent(
+                WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX);
     }
 
     /**
-     * Verify that we can change the minimum number of tx successes when rx success is 0
-     * to trigger data stall from settings
+     * Verify that we can change the threshold of Tx packet error rate to trigger a data stall
+     * from DeviceConfigFacade
      */
     @Test
-    public void verifyDataStallRxFailureSettingsChange() throws Exception {
-        when(mFacade.getIntegerSetting(mContext,
-                Settings.Global.WIFI_DATA_STALL_MIN_TX_SUCCESS_WITHOUT_RX,
-                WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT))
-                .thenReturn(WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT + 1);
-        mWifiDataStall.loadSettings();
-        verify(mWifiMetrics, times(2)).setWifiDataStallMinTxBad(WifiDataStall.MIN_TX_BAD_DEFAULT);
-        verify(mWifiMetrics).setWifiDataStallMinRxWithoutTx(
-                WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT + 1);
-
-        mNewLlStats.txmpdu_be =
-                mOldLlStats.txmpdu_be + WifiDataStall.MIN_TX_SUCCESS_WITHOUT_RX_DEFAULT;
+    public void verifyDataStallTxPerThrDeviceConfigChange() throws Exception {
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(10L);
+        when(mDeviceConfigFacade.getDataStallTxPerThr()).thenReturn(
+                DeviceConfigFacade.DEFAULT_DATA_STALL_TX_PER_THR + 1);
+        mOnPropertiesChangedListenerCaptor.getValue().onPropertiesChanged(null);
+
         assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verifyUpdateWifiIsUnusableLinkLayerStats();
-        verify(mWifiMetrics, never()).logWifiIsUnusableEvent(anyInt());
+        when(mClock.getElapsedSinceBootMillis()).thenReturn(
+                10L + DeviceConfigFacade.DEFAULT_DATA_STALL_DURATION_MS);
+        assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
+        verify(mWifiMetrics, never()).logWifiIsUnusableEvent(
+                WifiIsUnusableEvent.TYPE_DATA_STALL_BAD_TX);
     }
 
     /**
@@ -184,7 +244,7 @@ public class WifiDataStallTest {
     @Test
     public void verifyNoDataStallWhenNoFail() throws Exception {
         assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verify(mWifiMetrics, never()).resetWifiIsUnusableLinkLayerStats();
         verifyUpdateWifiIsUnusableLinkLayerStats();
         verify(mWifiMetrics, never()).logWifiIsUnusableEvent(anyInt());
@@ -196,11 +256,10 @@ public class WifiDataStallTest {
      */
     @Test
     public void verifyNoDataStallBigTimeGap() throws Exception {
-        mNewLlStats.lostmpdu_be = mOldLlStats.lostmpdu_be + WifiDataStall.MIN_TX_BAD_DEFAULT;
         mNewLlStats.timeStampInMs = mOldLlStats.timeStampInMs
                 + WifiDataStall.MAX_MS_DELTA_FOR_DATA_STALL + 1;
         assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verifyUpdateWifiIsUnusableLinkLayerStats();
         verify(mWifiMetrics, never()).logWifiIsUnusableEvent(anyInt());
     }
@@ -212,7 +271,7 @@ public class WifiDataStallTest {
     public void verifyReset() throws Exception {
         mNewLlStats.lostmpdu_be = mOldLlStats.lostmpdu_be - 1;
         assertEquals(WifiIsUnusableEvent.TYPE_UNKNOWN,
-                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats));
+                mWifiDataStall.checkForDataStall(mOldLlStats, mNewLlStats, mWifiInfo));
         verify(mWifiMetrics).resetWifiIsUnusableLinkLayerStats();
         verify(mWifiMetrics, never()).updateWifiIsUnusableLinkLayerStats(
                 anyLong(), anyLong(), anyLong(), anyLong(), anyLong());