WifiMetrics: add metric for alert reasons

Add metric to track the number of alerts triggered
by Wifi driver/firmware. This will give us a
concrete measurement of stability in the field.

BUG=29158746
TEST=tests/wifitests/runtests.sh

Change-Id: I435e5d792a97c197fe685e5b2c05d7b8efda62f0

5 files changed, 125 insertions, 10 deletions

diff --git a/service/java/com/android/server/wifi/WifiLoggerHal.java b/service/java/com/android/server/wifi/WifiLoggerHal.java
index 8a0276480..0294e9bf7 100644
--- a/service/java/com/android/server/wifi/WifiLoggerHal.java
+++ b/service/java/com/android/server/wifi/WifiLoggerHal.java
@@ -46,4 +46,9 @@ public class WifiLoggerHal {
     public static final byte RX_PKT_FATE_DRV_DROP_INVALID = 8;
     public static final byte RX_PKT_FATE_DRV_DROP_NOBUFS = 9;
     public static final byte RX_PKT_FATE_DRV_DROP_OTHER = 10;
+
+    /** These aren't formally part of the HAL. But they probably should be, eventually. */
+    public static final byte WIFI_ALERT_REASON_RESERVED = 0;
+    public static final byte WIFI_ALERT_REASON_MIN = 0;
+    public static final byte WIFI_ALERT_REASON_MAX = 64;
 }
diff --git a/service/java/com/android/server/wifi/WifiMetrics.java b/service/java/com/android/server/wifi/WifiMetrics.java
index 0dc5ccf2e..4547466c3 100644
--- a/service/java/com/android/server/wifi/WifiMetrics.java
+++ b/service/java/com/android/server/wifi/WifiMetrics.java
@@ -76,11 +76,14 @@ public class WifiMetrics {
      * combination. Indexed by WifiLog.WifiState * (1 + screenOn)
      */
     private final SparseIntArray mWifiSystemStateEntries = new SparseIntArray();
+    /** Mapping of RSSI values to counts. */
+    private final SparseIntArray mRssiPollCounts = new SparseIntArray();
+    /** Mapping of alert reason to the respective alert count. */
+    private final SparseIntArray mWifiAlertReasonCounts = new SparseIntArray();
     /**
      * Records the elapsedRealtime (in seconds) that represents the beginning of data
      * capture for for this WifiMetricsProto
      */
-    private final SparseIntArray mRssiPollCounts = new SparseIntArray();
     private long mRecordStartTimeSec;
 
     class RouterFingerPrint {
@@ -806,6 +809,22 @@ public class WifiMetrics {
         }
     }
 
+    /**
+     * Increments the count of alerts by alert reason.
+     *
+     * @param reason The cause of the alert. The reason values are driver-specific.
+     */
+    public void incrementAlertReasonCount(int reason) {
+        if (reason > WifiLoggerHal.WIFI_ALERT_REASON_MAX
+                || reason < WifiLoggerHal.WIFI_ALERT_REASON_MIN) {
+            reason = WifiLoggerHal.WIFI_ALERT_REASON_RESERVED;
+        }
+        synchronized (mLock) {
+            int alertCount = mWifiAlertReasonCounts.get(reason);
+            mWifiAlertReasonCounts.put(reason, alertCount + 1);
+        }
+    }
+
     public static final String PROTO_DUMP_ARG = "wifiMetricsProto";
     /**
      * Dump all WifiMetrics. Collects some metrics from ConfigStore, Settings and WifiManager
@@ -930,6 +949,21 @@ public class WifiMetrics {
                     sb.append(mRssiPollCounts.get(i) + " ");
                 }
                 pw.println("  " + sb.toString());
+                pw.print("mWifiLogProto.alertReasonCounts=");
+                sb.setLength(0);
+                for (int i = WifiLoggerHal.WIFI_ALERT_REASON_MIN;
+                        i <= WifiLoggerHal.WIFI_ALERT_REASON_MAX; i++) {
+                    int count = mWifiAlertReasonCounts.get(i);
+                    if (count > 0) {
+                        sb.append("(" + i + "," + count + "),");
+                    }
+                }
+                if (sb.length() > 1) {
+                    sb.setLength(sb.length() - 1);  // strip trailing comma
+                    pw.println(sb.toString());
+                } else {
+                    pw.println("()");
+                }
             }
         }
     }
@@ -943,6 +977,7 @@ public class WifiMetrics {
     private void consolidateProto(boolean incremental) {
         List<WifiMetricsProto.ConnectionEvent> events = new ArrayList<>();
         List<WifiMetricsProto.RssiPollCount> rssis = new ArrayList<>();
+        List<WifiMetricsProto.AlertReasonCount> alertReasons = new ArrayList<>();
         synchronized (mLock) {
             for (ConnectionEvent event : mConnectionEventList) {
                 // If this is not incremental, dump full ConnectionEvent list
@@ -1000,6 +1035,18 @@ public class WifiMetrics {
                 rssis.add(keyVal);
             }
             mWifiLogProto.rssiPollRssiCount = rssis.toArray(mWifiLogProto.rssiPollRssiCount);
+
+            /**
+             * Convert the SparseIntArray of alert reasons and counts to the proto's repeated
+             * IntKeyVal array.
+             */
+            for (int i = 0; i < mWifiAlertReasonCounts.size(); i++) {
+                WifiMetricsProto.AlertReasonCount keyVal = new WifiMetricsProto.AlertReasonCount();
+                keyVal.reason = mWifiAlertReasonCounts.keyAt(i);
+                keyVal.count = mWifiAlertReasonCounts.valueAt(i);
+                alertReasons.add(keyVal);
+            }
+            mWifiLogProto.alertReasonCount = alertReasons.toArray(mWifiLogProto.alertReasonCount);
         }
     }
 
@@ -1016,6 +1063,7 @@ public class WifiMetrics {
             mWifiSystemStateEntries.clear();
             mRecordStartTimeSec = mClock.elapsedRealtime() / 1000;
             mRssiPollCounts.clear();
+            mWifiAlertReasonCounts.clear();
             mWifiLogProto.clear();
         }
     }
diff --git a/service/java/com/android/server/wifi/WifiStateMachine.java b/service/java/com/android/server/wifi/WifiStateMachine.java
index 603c4757c..541d72755 100644
--- a/service/java/com/android/server/wifi/WifiStateMachine.java
+++ b/service/java/com/android/server/wifi/WifiStateMachine.java
@@ -4189,7 +4189,9 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
                 case CMD_FIRMWARE_ALERT:
                     if (mWifiLogger != null) {
                         byte[] buffer = (byte[])message.obj;
-                        mWifiLogger.captureAlertData(message.arg1, buffer);
+                        int alertReason = message.arg1;
+                        mWifiLogger.captureAlertData(alertReason, buffer);
+                        mWifiMetrics.incrementAlertReasonCount(alertReason);
                     }
                     break;
                 case CMD_GET_LINK_LAYER_STATS:
diff --git a/service/proto/wifi.proto b/service/proto/wifi.proto
index 3b0e8544b..05ca06de8 100644
--- a/service/proto/wifi.proto
+++ b/service/proto/wifi.proto
@@ -189,6 +189,9 @@ message WifiLog {
 
   // Counts the occurrences of each individual RSSI poll level
   repeated RssiPollCount rssi_poll_rssi_count = 35;
+
+  // Counts the occurrences of each alert reason.
+  repeated AlertReasonCount alert_reason_count = 47;
 }
 
 // Information that gets logged for every WiFi connection.
@@ -349,3 +352,12 @@ message RssiPollCount {
   // Number of RSSI polls with 'rssi'
   optional int32 count = 2;
 }
+
+// Number of occurrences of a specific alert reason value
+message AlertReasonCount {
+  // Alert reason
+  optional int32 reason = 1;
+
+  // Number of alerts with |reason|.
+  optional int32 count = 2;
+}
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiMetricsTest.java b/tests/wifitests/src/com/android/server/wifi/WifiMetricsTest.java
index 011682b81..b10f5734a 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiMetricsTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiMetricsTest.java
@@ -104,15 +104,32 @@ public class WifiMetricsTest {
         mDeserializedWifiMetrics = WifiMetricsProto.WifiLog.parseFrom(protoBytes);
     }
 
+    /** Verifies that dump() includes the expected header */
     @Test
-    public void dumpHumanReadable() throws Exception {
-        ByteArrayOutputStream stream = new ByteArrayOutputStream();
-        PrintWriter writer = new PrintWriter(stream);
-        String[] args = new String[0];
-        mWifiMetrics.dump(null, writer, args);
-        writer.flush();
-        assertTrue("stream.toString().contains(\"WifiMetrics\")",
-                stream.toString().contains("WifiMetrics"));
+    public void stateDumpIncludesHeader() throws Exception {
+        assertStringContains(getStateDump(), "WifiMetrics");
+    }
+
+    /** Verifies that dump() includes correct alert count when there are no alerts. */
+    @Test
+    public void stateDumpAlertCountIsCorrectWithNoAlerts() throws Exception {
+        assertStringContains(getStateDump(), "mWifiLogProto.alertReasonCounts=()");
+    }
+
+    /** Verifies that dump() includes correct alert count when there is one alert. */
+    @Test
+    public void stateDumpAlertCountIsCorrectWithOneAlert() throws Exception {
+        mWifiMetrics.incrementAlertReasonCount(1);
+        assertStringContains(getStateDump(), "mWifiLogProto.alertReasonCounts=(1,1)");
+    }
+
+    /** Verifies that dump() includes correct alert count when there are multiple alerts. */
+    @Test
+    public void stateDumpAlertCountIsCorrectWithMultipleAlerts() throws Exception {
+        mWifiMetrics.incrementAlertReasonCount(1);
+        mWifiMetrics.incrementAlertReasonCount(1);
+        mWifiMetrics.incrementAlertReasonCount(16);
+        assertStringContains(getStateDump(), "mWifiLogProto.alertReasonCounts=(1,2),(16,1)");
     }
 
     @Test
@@ -243,6 +260,14 @@ public class WifiMetricsTest {
                 mWifiMetrics.incrementRssiPollRssiCount(FIRST_RSSI_LEVEL + i);
             }
         }
+        // Test alert-reason clamping.
+        mWifiMetrics.incrementAlertReasonCount(WifiLoggerHal.WIFI_ALERT_REASON_MIN - 1);
+        mWifiMetrics.incrementAlertReasonCount(WifiLoggerHal.WIFI_ALERT_REASON_MAX + 1);
+        // Simple cases for alert reason.
+        mWifiMetrics.incrementAlertReasonCount(1);
+        mWifiMetrics.incrementAlertReasonCount(1);
+        mWifiMetrics.incrementAlertReasonCount(1);
+        mWifiMetrics.incrementAlertReasonCount(2);
     }
 
     /**
@@ -324,6 +349,10 @@ public class WifiMetricsTest {
             assertEquals(FIRST_RSSI_LEVEL + i, mDeserializedWifiMetrics.rssiPollRssiCount[i].rssi);
             assertEquals(i + 1, mDeserializedWifiMetrics.rssiPollRssiCount[i].count);
         }
+        assertEquals(2, mDeserializedWifiMetrics.alertReasonCount[0].count);  // Clamped reasons.
+        assertEquals(3, mDeserializedWifiMetrics.alertReasonCount[1].count);
+        assertEquals(1, mDeserializedWifiMetrics.alertReasonCount[2].count);
+        assertEquals(3, mDeserializedWifiMetrics.alertReasonCount.length);
     }
 
     /**
@@ -461,6 +490,8 @@ public class WifiMetricsTest {
         dumpProtoAndDeserialize();
         //Check there are only 3 connection events
         assertEquals(mDeserializedWifiMetrics.connectionEvent.length, 4);
+        assertEquals(mDeserializedWifiMetrics.rssiPollRssiCount.length, 0);
+        assertEquals(mDeserializedWifiMetrics.alertReasonCount.length, 0);
 
         // Create 2 ConnectionEvents
         mWifiMetrics.startConnectionEvent(null,  "BLUE",
@@ -479,4 +510,21 @@ public class WifiMetricsTest {
         //Check there are only 2 connection events
         assertEquals(mDeserializedWifiMetrics.connectionEvent.length, 2);
     }
+
+    private void assertStringContains(
+            String actualString, String expectedSubstring) {
+        assertTrue("Expected text not found in: " + actualString,
+                actualString.contains(expectedSubstring));
+    }
+
+    private String getStateDump() {
+        ByteArrayOutputStream stream = new ByteArrayOutputStream();
+        PrintWriter writer = new PrintWriter(stream);
+        String[] args = new String[0];
+        mWifiMetrics.dump(null, writer, args);
+        writer.flush();
+        return stream.toString();
+    }
 }
+
+