Wifi usability: Separate thresholds on link speed and tput into tx and

rx ones

In addition, make the thresholds on link speed to detect Wifi data stall
configurable through DeviceConfigFacade.

Bug: 157751388
Test: atest com.android.server.wifi
Test: atest android.net.wifi

Signed-off-by: Mingguang Xu <mingguangxu@google.com>
Change-Id: I3d0db15b10df055dfe3ac80e7305e6f62022d801

2 files changed, 82 insertions, 28 deletions

diff --git a/service/java/com/android/server/wifi/DeviceConfigFacade.java b/service/java/com/android/server/wifi/DeviceConfigFacade.java
index d25a50a10..cfd2ad081 100644
--- a/service/java/com/android/server/wifi/DeviceConfigFacade.java
+++ b/service/java/com/android/server/wifi/DeviceConfigFacade.java
@@ -53,10 +53,14 @@ public class DeviceConfigFacade {
     public static final int DEFAULT_DATA_STALL_TX_PER_THR = 90;
     // Default threshold of CCA level above which to trigger a data stall
     public static final int DEFAULT_DATA_STALL_CCA_LEVEL_THR = CHANNEL_UTILIZATION_SCALE;
-    // Default low threshold of L2 sufficient throughput in Kbps
-    public static final int DEFAULT_TPUT_SUFFICIENT_THR_LOW_KBPS = 1000;
-    // Default high threshold of L2 sufficient throughput in Kbps
-    public static final int DEFAULT_TPUT_SUFFICIENT_THR_HIGH_KBPS = 4000;
+    // Default low threshold of L2 sufficient Tx throughput in Kbps
+    public static final int DEFAULT_TX_TPUT_SUFFICIENT_THR_LOW_KBPS = 1000;
+    // Default high threshold of L2 sufficient Tx throughput in Kbps
+    public static final int DEFAULT_TX_TPUT_SUFFICIENT_THR_HIGH_KBPS = 4000;
+    // Default low threshold of L2 sufficient Rx throughput in Kbps
+    public static final int DEFAULT_RX_TPUT_SUFFICIENT_THR_LOW_KBPS = 1000;
+    // Default high threshold of L2 sufficient Rx throughput in Kbps
+    public static final int DEFAULT_RX_TPUT_SUFFICIENT_THR_HIGH_KBPS = 4000;
     // Numerator part of default threshold of L2 throughput over L3 throughput ratio
     public static final int DEFAULT_TPUT_SUFFICIENT_RATIO_THR_NUM = 2;
     // Denominator part of default threshold of L2 throughput over L3 throughput ratio
@@ -97,6 +101,12 @@ public class DeviceConfigFacade {
     static final int DEFAULT_BUG_REPORT_THRESHOLD_EXTRA_RATIO = 2;
     // Default overlapping connection duration threshold in ms to trigger bug report
     static final int DEFAULT_OVERLAPPING_CONNECTION_DURATION_THRESHOLD_MS = 75_000;
+    // At low traffic, Tx link speed values below the following threshold
+    // are ignored because it could be due to low rate management frames
+    static final int DEFAULT_TX_LINK_SPEED_LOW_THRESHOLD_MBPS = 9;
+    // At low traffic, Rx link speed values below the following threshold
+    // are ignored because it could be due to low rate management frames
+    static final int DEFAULT_RX_LINK_SPEED_LOW_THRESHOLD_MBPS = 9;
 
     // Cached values of fields updated via updateDeviceConfigFlags()
     private boolean mIsAbnormalConnectionBugreportEnabled;
@@ -106,8 +116,10 @@ public class DeviceConfigFacade {
     private int mDataStallRxTputThrKbps;
     private int mDataStallTxPerThr;
     private int mDataStallCcaLevelThr;
-    private int mTputSufficientLowThrKbps;
-    private int mTputSufficientHighThrKbps;
+    private int mTxTputSufficientLowThrKbps;
+    private int mTxTputSufficientHighThrKbps;
+    private int mRxTputSufficientLowThrKbps;
+    private int mRxTputSufficientHighThrKbps;
     private int mTputSufficientRatioThrNum;
     private int mTputSufficientRatioThrDen;
     private int mTxPktPerSecondThr;
@@ -136,6 +148,8 @@ public class DeviceConfigFacade {
     private int mBugReportThresholdExtraRatio;
     private boolean mIsOverlappingConnectionBugreportEnabled;
     private int mOverlappingConnectionDurationThresholdMs;
+    private int mTxLinkSpeedLowThresholdMbps;
+    private int mRxLinkSpeedLowThresholdMbps;
 
     public DeviceConfigFacade(Context context, Handler handler, WifiMetrics wifiMetrics) {
         mContext = context;
@@ -173,10 +187,14 @@ public class DeviceConfigFacade {
         mWifiMetrics.setDataStallTxPerThr(mDataStallTxPerThr);
         mWifiMetrics.setDataStallCcaLevelThr(mDataStallCcaLevelThr);
 
-        mTputSufficientLowThrKbps = DeviceConfig.getInt(NAMESPACE,
-                "tput_sufficient_low_thr_kbps", DEFAULT_TPUT_SUFFICIENT_THR_LOW_KBPS);
-        mTputSufficientHighThrKbps = DeviceConfig.getInt(NAMESPACE,
-                "tput_sufficient_high_thr_kbps", DEFAULT_TPUT_SUFFICIENT_THR_HIGH_KBPS);
+        mTxTputSufficientLowThrKbps = DeviceConfig.getInt(NAMESPACE,
+                "tput_sufficient_low_thr_kbps", DEFAULT_TX_TPUT_SUFFICIENT_THR_LOW_KBPS);
+        mTxTputSufficientHighThrKbps = DeviceConfig.getInt(NAMESPACE,
+                "tput_sufficient_high_thr_kbps", DEFAULT_TX_TPUT_SUFFICIENT_THR_HIGH_KBPS);
+        mRxTputSufficientLowThrKbps = DeviceConfig.getInt(NAMESPACE,
+                "rx_tput_sufficient_low_thr_kbps", DEFAULT_RX_TPUT_SUFFICIENT_THR_LOW_KBPS);
+        mRxTputSufficientHighThrKbps = DeviceConfig.getInt(NAMESPACE,
+                "rx_tput_sufficient_high_thr_kbps", DEFAULT_RX_TPUT_SUFFICIENT_THR_HIGH_KBPS);
         mTputSufficientRatioThrNum = DeviceConfig.getInt(NAMESPACE,
                 "tput_sufficient_ratio_thr_num", DEFAULT_TPUT_SUFFICIENT_RATIO_THR_NUM);
         mTputSufficientRatioThrDen = DeviceConfig.getInt(NAMESPACE,
@@ -254,6 +272,12 @@ public class DeviceConfigFacade {
         mOverlappingConnectionDurationThresholdMs = DeviceConfig.getInt(NAMESPACE,
                 "overlapping_connection_duration_threshold_ms",
                 DEFAULT_OVERLAPPING_CONNECTION_DURATION_THRESHOLD_MS);
+        mTxLinkSpeedLowThresholdMbps = DeviceConfig.getInt(NAMESPACE,
+                "tx_link_speed_low_threshold_mbps",
+                DEFAULT_TX_LINK_SPEED_LOW_THRESHOLD_MBPS);
+        mRxLinkSpeedLowThresholdMbps = DeviceConfig.getInt(NAMESPACE,
+                "rx_link_speed_low_threshold_mbps",
+                DEFAULT_RX_LINK_SPEED_LOW_THRESHOLD_MBPS);
     }
 
     private Set<String> getUnmodifiableSetQuoted(String key) {
@@ -321,15 +345,29 @@ public class DeviceConfigFacade {
     /**
      * Gets the low threshold of L2 throughput below which L2 throughput is always insufficient
      */
-    public int getTputSufficientLowThrKbps() {
-        return mTputSufficientLowThrKbps;
+    public int getTxTputSufficientLowThrKbps() {
+        return mTxTputSufficientLowThrKbps;
     }
 
     /**
      * Gets the high threshold of L2 throughput above which L2 throughput is always sufficient
      */
-    public int getTputSufficientHighThrKbps() {
-        return mTputSufficientHighThrKbps;
+    public int getTxTputSufficientHighThrKbps() {
+        return mTxTputSufficientHighThrKbps;
+    }
+
+    /**
+     * Gets the low threshold of L2 throughput below which L2 Rx throughput is always insufficient
+     */
+    public int getRxTputSufficientLowThrKbps() {
+        return mRxTputSufficientLowThrKbps;
+    }
+
+    /**
+     * Gets the high threshold of L2 throughput above which L2 Rx throughput is always sufficient
+     */
+    public int getRxTputSufficientHighThrKbps() {
+        return mRxTputSufficientHighThrKbps;
     }
 
     /**
@@ -531,4 +569,18 @@ public class DeviceConfigFacade {
     public int getOverlappingConnectionDurationThresholdMs() {
         return mOverlappingConnectionDurationThresholdMs;
     }
+
+    /**
+     * Gets the threshold of link speed below which Tx link speed is ignored at low traffic
+     */
+    public int getTxLinkSpeedLowThresholdMbps() {
+        return mTxLinkSpeedLowThresholdMbps;
+    }
+
+    /**
+     * Gets the threshold of link speed below which Rx link speed is ignored at low traffic
+     */
+    public int getRxLinkSpeedLowThresholdMbps() {
+        return mRxLinkSpeedLowThresholdMbps;
+    }
 }
diff --git a/service/java/com/android/server/wifi/WifiDataStall.java b/service/java/com/android/server/wifi/WifiDataStall.java
index 8dea0df61..87b9a1b68 100644
--- a/service/java/com/android/server/wifi/WifiDataStall.java
+++ b/service/java/com/android/server/wifi/WifiDataStall.java
@@ -41,9 +41,6 @@ public class WifiDataStall {
     private static final String TAG = "WifiDataStall";
     private boolean mVerboseLoggingEnabled = false;
     public static final int INVALID_THROUGHPUT = -1;
-    // At low traffic, link speed values below the following threshold
-    // are ignored because it could be due to low rate management frames
-    public static final int LINK_SPEED_LOW_THRESHOLD_MBPS = 9;
     // Maximum time gap between two WifiLinkLayerStats to trigger a data stall
     public static final int MAX_MS_DELTA_FOR_DATA_STALL = 60 * 1000; // 1 minute
     // Maximum time that a data stall start time stays valid.
@@ -306,7 +303,8 @@ public class WifiDataStall {
 
         if (txLinkSpeedMbps > 0) {
             // Exclude update with low rate management frames
-            if (isTxTrafficHigh || txLinkSpeedMbps > LINK_SPEED_LOW_THRESHOLD_MBPS) {
+            if (isTxTrafficHigh
+                    || txLinkSpeedMbps > mDeviceConfigFacade.getTxLinkSpeedLowThresholdMbps()) {
                 mTxTputKbps = (int) ((long) txLinkSpeedMbps * 1000 * (100 - txPer) / 100
                         * (CHANNEL_UTILIZATION_SCALE  - ccaLevel) / CHANNEL_UTILIZATION_SCALE);
             }
@@ -317,7 +315,8 @@ public class WifiDataStall {
 
         if (rxLinkSpeedMbps > 0) {
             // Exclude update with low rate management frames
-            if (isRxTrafficHigh || rxLinkSpeedMbps > LINK_SPEED_LOW_THRESHOLD_MBPS) {
+            if (isRxTrafficHigh
+                    || rxLinkSpeedMbps > mDeviceConfigFacade.getRxLinkSpeedLowThresholdMbps()) {
                 mRxTputKbps = (int) ((long) rxLinkSpeedMbps * 1000
                         * (CHANNEL_UTILIZATION_SCALE  - ccaLevel) / CHANNEL_UTILIZATION_SCALE);
             }
@@ -438,8 +437,8 @@ public class WifiDataStall {
         mLastTxBytes = txBytes;
         mLastRxBytes = rxBytes;
 
-        boolean isTxTputSufficient = isL2ThroughputSufficient(l2TxTputKbps, l3TxTputKbps);
-        boolean isRxTputSufficient = isL2ThroughputSufficient(l2RxTputKbps, l3RxTputKbps);
+        boolean isTxTputSufficient = isL2ThroughputSufficient(l2TxTputKbps, l3TxTputKbps, false);
+        boolean isRxTputSufficient = isL2ThroughputSufficient(l2RxTputKbps, l3RxTputKbps, true);
         isTxTputSufficient = detectAndOverrideFalseInSufficient(
                 isTxTputSufficient, isTxTrafficHigh, mIsThroughputSufficient);
         isRxTputSufficient = detectAndOverrideFalseInSufficient(
@@ -466,17 +465,20 @@ public class WifiDataStall {
      * 3) L3 tput is not low and L2 tput is above its high threshold
      * 4) L2 tput is invalid
      */
-    private boolean isL2ThroughputSufficient(int l2TputKbps, int l3TputKbps) {
+    private boolean isL2ThroughputSufficient(int l2TputKbps, int l3TputKbps, boolean isForRxTput) {
         if (l2TputKbps == INVALID_THROUGHPUT) return true;
+        int tputSufficientLowThrKbps = mDeviceConfigFacade.getTxTputSufficientLowThrKbps();
+        int tputSufficientHighThrKbps = mDeviceConfigFacade.getTxTputSufficientHighThrKbps();
+        if (isForRxTput) {
+            tputSufficientLowThrKbps = mDeviceConfigFacade.getRxTputSufficientLowThrKbps();
+            tputSufficientHighThrKbps = mDeviceConfigFacade.getRxTputSufficientHighThrKbps();
+        }
         boolean isL3TputLow = (l3TputKbps * mDeviceConfigFacade.getTputSufficientRatioThrDen())
-                < (mDeviceConfigFacade.getTputSufficientLowThrKbps()
-                * mDeviceConfigFacade.getTputSufficientRatioThrNum());
-        boolean isL2TputAboveLowThr =
-                l2TputKbps >= mDeviceConfigFacade.getTputSufficientLowThrKbps();
+                < (tputSufficientLowThrKbps * mDeviceConfigFacade.getTputSufficientRatioThrNum());
+        boolean isL2TputAboveLowThr = l2TputKbps >= tputSufficientLowThrKbps;
         if (isL3TputLow) return isL2TputAboveLowThr;
 
-        boolean isL2TputAboveHighThr =
-                l2TputKbps >= mDeviceConfigFacade.getTputSufficientHighThrKbps();
+        boolean isL2TputAboveHighThr = l2TputKbps >= tputSufficientHighThrKbps;
         boolean isL2L3TputRatioAboveThr =
                 (l2TputKbps * mDeviceConfigFacade.getTputSufficientRatioThrDen())
                 >= (l3TputKbps * mDeviceConfigFacade.getTputSufficientRatioThrNum());