WifiStateMachine: clean up dead code

Cleaned up the dead code from the original exponential back off
scan implementation.

Bug: 28750989
Bug: 28070598

Change-Id: I8abf82cdaa3530fb514794b4004c5d3f15950672
Tests: Wifi Unit Tests, manual test

3 files changed, 7 insertions, 211 deletions

diff --git a/service/java/com/android/server/wifi/WifiConfigManager.java b/service/java/com/android/server/wifi/WifiConfigManager.java
index de4ec1f31..b736aa93c 100644
--- a/service/java/com/android/server/wifi/WifiConfigManager.java
+++ b/service/java/com/android/server/wifi/WifiConfigManager.java
@@ -218,22 +218,16 @@ public class WifiConfigManager {
     };
 
     public final AtomicBoolean mEnableAutoJoinWhenAssociated = new AtomicBoolean();
-    public final AtomicBoolean mEnableFullBandScanWhenAssociated = new AtomicBoolean(true);
     public final AtomicBoolean mEnableChipWakeUpWhenAssociated = new AtomicBoolean(true);
     public final AtomicBoolean mEnableRssiPollWhenAssociated = new AtomicBoolean(true);
     public final AtomicInteger mThresholdSaturatedRssi5 = new AtomicInteger();
     public final AtomicInteger mThresholdQualifiedRssi24 = new AtomicInteger();
     public final AtomicInteger mEnableVerboseLogging = new AtomicInteger(0);
-    public final AtomicInteger mAssociatedFullScanBackoff =
-            new AtomicInteger(); // Will be divided by 8 by WifiStateMachine
     public final AtomicInteger mAlwaysEnableScansWhileAssociated = new AtomicInteger(0);
     public final AtomicInteger mMaxNumActiveChannelsForPartialScans = new AtomicInteger();
-    public final AtomicInteger mWifiDisconnectedShortScanIntervalMs = new AtomicInteger();
-    public final AtomicInteger mWifiAssociatedShortScanIntervalMs = new AtomicInteger();
 
     public boolean mEnableLinkDebouncing;
     public boolean mEnableWifiCellularHandoverUserTriggeredAdjustment;
-    public int mAssociatedFullScanMaxIntervalMs;
     public int mNetworkSwitchingBlackListPeriodMs;
     public int mBadLinkSpeed24;
     public int mBadLinkSpeed5;
@@ -352,18 +346,10 @@ public class WifiConfigManager {
             mLocalLog = null;
         }
 
-        mWifiAssociatedShortScanIntervalMs.set(mContext.getResources().getInteger(
-                R.integer.config_wifi_associated_short_scan_interval));
-        mWifiDisconnectedShortScanIntervalMs.set(mContext.getResources().getInteger(
-                R.integer.config_wifi_disconnected_short_scan_interval));
         mOnlyLinkSameCredentialConfigurations = mContext.getResources().getBoolean(
                 R.bool.config_wifi_only_link_same_credential_configurations);
         mMaxNumActiveChannelsForPartialScans.set(mContext.getResources().getInteger(
                 R.integer.config_wifi_framework_associated_partial_scan_max_num_active_channels));
-        mAssociatedFullScanMaxIntervalMs = mContext.getResources().getInteger(
-                R.integer.config_wifi_framework_associated_full_scan_max_interval);
-        mAssociatedFullScanBackoff.set(mContext.getResources().getInteger(
-                R.integer.config_wifi_framework_associated_full_scan_backoff));
         mEnableLinkDebouncing = mContext.getResources().getBoolean(
                 R.bool.config_wifi_enable_disconnection_debounce);
         mBandAward5Ghz.set(mContext.getResources().getInteger(
diff --git a/service/java/com/android/server/wifi/WifiConnectivityManager.java b/service/java/com/android/server/wifi/WifiConnectivityManager.java
index f2ea62d1a..f38e36768 100644
--- a/service/java/com/android/server/wifi/WifiConnectivityManager.java
+++ b/service/java/com/android/server/wifi/WifiConnectivityManager.java
@@ -676,7 +676,9 @@ public class WifiConnectivityManager {
                         > mConfigManager.MAX_TX_PACKET_FOR_FULL_SCANS
                 || mWifiInfo.rxSuccessRate
                         > mConfigManager.MAX_RX_PACKET_FOR_FULL_SCANS) {
-            localLog("No full band scan due to heavy traffic");
+            localLog("No full band scan due to heavy traffic, txSuccessRate="
+                        + mWifiInfo.txSuccessRate + " rxSuccessRate="
+                        + mWifiInfo.rxSuccessRate);
             isFullBandScan = false;
 
             if (mWifiInfo.txSuccessRate
diff --git a/service/java/com/android/server/wifi/WifiStateMachine.java b/service/java/com/android/server/wifi/WifiStateMachine.java
index 1079ae112..82ede5694 100644
--- a/service/java/com/android/server/wifi/WifiStateMachine.java
+++ b/service/java/com/android/server/wifi/WifiStateMachine.java
@@ -276,7 +276,6 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
     private final Queue<Message> mBufferedScanMsg = new LinkedList<Message>();
     private WorkSource mScanWorkSource = null;
     private static final int UNKNOWN_SCAN_SOURCE = -1;
-    private static final int SCAN_ALARM_SOURCE = -2;
     private static final int ADD_OR_UPDATE_SOURCE = -3;
     private static final int SET_ALLOW_UNTRUSTED_SOURCE = -4;
     private static final int ENABLE_WIFI = -5;
@@ -869,24 +868,6 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
     private long mSupplicantScanIntervalMs;
 
     /**
-     * timeStamp of last full band scan we perfoemed for autojoin while connected with screen lit
-     */
-    private long lastFullBandConnectedTimeMilli;
-
-    /**
-     * time interval to the next full band scan we will perform for
-     * autojoin while connected with screen lit
-     */
-    private long fullBandConnectedTimeIntervalMilli;
-
-    /**
-     * max time interval to the next full band scan we will perform for
-     * autojoin while connected with screen lit
-     * Max time is 5 minutes
-     */
-    private static final long maxFullBandConnectedTimeIntervalMilli = 1000 * 60 * 5;
-
-    /**
      * Minimum time interval between enabling all networks.
      * A device can end up repeatedly connecting to a bad network on screen on/off toggle
      * due to enabling every time. We add a threshold to avoid this.
@@ -2438,8 +2419,6 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
                     for(int freq : lastScanFreqs) {
                         sb.append(freq).append(",");
                     }
-                } else {
-                    sb.append(" fiv=").append(fullBandConnectedTimeIntervalMilli);
                 }
                 report = reportOnTime();
                 if (report != null) {
@@ -3539,15 +3518,6 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
         /* Reset roaming parameters */
         mAutoRoaming = false;
 
-        /**
-         *  fullBandConnectedTimeIntervalMilli:
-         *  - start scans at mWifiConfigManager.mWifiAssociatedShortScanIntervalMs seconds
-         *    interval
-         *  - exponentially increase to mWifiConfigManager.mAssociatedFullScanMaxIntervalMs
-         *  Initialize to sane value = 20 seconds
-         */
-        fullBandConnectedTimeIntervalMilli = 20 * 1000;
-
         setNetworkDetailedState(DetailedState.DISCONNECTED);
         if (mNetworkAgent != null) {
             mNetworkAgent.sendNetworkInfo(mNetworkInfo);
@@ -6583,147 +6553,6 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
                                 setAndEnableLastSelectedConfiguration(
                                         WifiConfiguration.INVALID_NETWORK_ID);
                     break;
-                case CMD_START_SCAN:
-                    if (DBG) {
-                        logd("CMD_START_SCAN source " + message.arg1
-                              + " txSuccessRate="+String.format( "%.2f", mWifiInfo.txSuccessRate)
-                              + " rxSuccessRate="+String.format( "%.2f", mWifiInfo.rxSuccessRate)
-                              + " targetRoamBSSID=" + mTargetRoamBSSID
-                              + " RSSI=" + mWifiInfo.getRssi());
-                    }
-                    if (message.arg1 == SCAN_ALARM_SOURCE) {
-                        // Check if the CMD_START_SCAN message is obsolete (and thus if it should
-                        // not be processed) and restart the scan if neede
-                        if (!mWifiConfigManager.getEnableAutoJoinWhenAssociated()) {
-                            return HANDLED;
-                        }
-
-                        if (mP2pConnected.get()) {
-                            logd("L2Connected CMD_START_SCAN source "
-                                    + message.arg1
-                                    + " " + message.arg2 + ", "
-                                    + " ignore because P2P is connected");
-                            messageHandlingStatus = MESSAGE_HANDLING_STATUS_DISCARD;
-                            return HANDLED;
-                        }
-                        boolean tryFullBandScan = false;
-                        boolean restrictChannelList = false;
-                        long now_ms = System.currentTimeMillis();
-                        if (DBG) {
-                            logd("CMD_START_SCAN with age="
-                                    + Long.toString(now_ms - lastFullBandConnectedTimeMilli)
-                                    + " interval=" + fullBandConnectedTimeIntervalMilli
-                                    + " maxinterval=" + maxFullBandConnectedTimeIntervalMilli);
-                        }
-
-                        if (mWifiConfigManager.mEnableFullBandScanWhenAssociated.get()
-                                && (now_ms - lastFullBandConnectedTimeMilli)
-                                > fullBandConnectedTimeIntervalMilli) {
-                            if (DBG) {
-                                logd("CMD_START_SCAN try full band scan age="
-                                         + Long.toString(now_ms - lastFullBandConnectedTimeMilli)
-                                         + " interval=" + fullBandConnectedTimeIntervalMilli
-                                         + " maxinterval=" + maxFullBandConnectedTimeIntervalMilli);
-                            }
-                            tryFullBandScan = true;
-                        }
-
-                        if (mWifiInfo.txSuccessRate
-                                        > mWifiConfigManager.MAX_TX_PACKET_FOR_FULL_SCANS
-                                || mWifiInfo.rxSuccessRate
-                                        > mWifiConfigManager.MAX_RX_PACKET_FOR_FULL_SCANS) {
-                            // Too much traffic at the interface, hence no full band scan
-                            if (DBG) {
-                                logd("CMD_START_SCAN prevent full band scan due to pkt rate");
-                            }
-                            tryFullBandScan = false;
-                        }
-
-                        if (mWifiInfo.txSuccessRate
-                                        > mWifiConfigManager.MAX_TX_PACKET_FOR_PARTIAL_SCANS
-                                || mWifiInfo.rxSuccessRate
-                                        > mWifiConfigManager.MAX_RX_PACKET_FOR_PARTIAL_SCANS) {
-                            // Don't scan if lots of packets are being sent
-                            restrictChannelList = true;
-                            if (mWifiConfigManager.mAlwaysEnableScansWhileAssociated.get() == 0) {
-                                if (DBG) {
-                                    logd("CMD_START_SCAN source " + message.arg1
-                                            + " ...and ignore scans"
-                                            + " tx="
-                                            + String.format("%.2f", mWifiInfo.txSuccessRate)
-                                            + " rx="
-                                            + String.format("%.2f", mWifiInfo.rxSuccessRate));
-                                }
-                                messageHandlingStatus = MESSAGE_HANDLING_STATUS_REFUSED;
-                                return HANDLED;
-                            }
-                        }
-
-                        WifiConfiguration currentConfiguration = getCurrentWifiConfiguration();
-                        if (DBG) {
-                            logd("CMD_START_SCAN full=" +
-                                    tryFullBandScan);
-                        }
-                        if (currentConfiguration != null) {
-                            if (fullBandConnectedTimeIntervalMilli <
-                                    mWifiConfigManager.mWifiAssociatedShortScanIntervalMs.get()) {
-                                // Sanity
-                                fullBandConnectedTimeIntervalMilli =
-                                        mWifiConfigManager
-                                                .mWifiAssociatedShortScanIntervalMs.get();
-                            }
-                            if (tryFullBandScan) {
-                                lastFullBandConnectedTimeMilli = now_ms;
-                                if (fullBandConnectedTimeIntervalMilli
-                                        < mWifiConfigManager.mAssociatedFullScanMaxIntervalMs) {
-                                    // Increase the interval
-                                    fullBandConnectedTimeIntervalMilli =
-                                            fullBandConnectedTimeIntervalMilli *
-                                                    mWifiConfigManager
-                                                            .mAssociatedFullScanBackoff.get() / 8;
-
-                                    if (DBG) {
-                                        logd("CMD_START_SCAN bump interval ="
-                                        + fullBandConnectedTimeIntervalMilli);
-                                    }
-                                }
-                                handleScanRequest(message);
-                            } else {
-                                if (!startScanForConfiguration(
-                                        currentConfiguration, restrictChannelList)) {
-                                    if (DBG) {
-                                        logd("starting scan, " +
-                                                " did not find channels -> full");
-                                    }
-                                    lastFullBandConnectedTimeMilli = now_ms;
-                                    if (fullBandConnectedTimeIntervalMilli
-                                            < mWifiConfigManager
-                                            .mAssociatedFullScanMaxIntervalMs) {
-                                        // Increase the interval
-                                        fullBandConnectedTimeIntervalMilli =
-                                                fullBandConnectedTimeIntervalMilli
-                                                        * mWifiConfigManager
-                                                                .mAssociatedFullScanBackoff.get()
-                                                        / 8;
-
-                                        if (DBG) {
-                                            logd("CMD_START_SCAN bump interval ="
-                                                    + fullBandConnectedTimeIntervalMilli);
-                                        }
-                                    }
-                                    handleScanRequest(message);
-                                }
-                            }
-
-                        } else {
-                            logd("CMD_START_SCAN : connected mode and no configuration");
-                            messageHandlingStatus = MESSAGE_HANDLING_STATUS_HANDLING_ERROR;
-                        }
-                    } else {
-                        // Not scan alarm source
-                        return NOT_HANDLED;
-                    }
-                    break;
                     /* Ignore connection to same network */
                 case WifiManager.CONNECT_NETWORK:
                     int netId = message.arg1;
@@ -7170,10 +6999,7 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
             updateDefaultRouteMacAddress(1000);
             if (DBG) {
                 log("Enter ConnectedState "
-                       + " mScreenOn=" + mScreenOn
-                       + " scanperiod="
-                       + Integer.toString(
-                            mWifiConfigManager.mWifiAssociatedShortScanIntervalMs.get()));
+                       + " mScreenOn=" + mScreenOn);
             }
 
             if (mWifiConnectivityManager != null) {
@@ -7477,9 +7303,7 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
         public void enter() {
 
             if (DBG) {
-                logd(" Enter DisconnectingState State scan interval "
-                        + mWifiConfigManager.mWifiDisconnectedShortScanIntervalMs.get()
-                        + " screenOn=" + mScreenOn);
+                logd(" Enter DisconnectingState State screenOn=" + mScreenOn);
             }
 
             // Make sure we disconnect: we enter this state prior to connecting to a new
@@ -7541,9 +7365,7 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
             }
 
             if (DBG) {
-                logd(" Enter DisconnectedState scan interval "
-                        + mWifiConfigManager.mWifiDisconnectedShortScanIntervalMs.get()
-                        + " screenOn=" + mScreenOn);
+                logd(" Enter DisconnectedState screenOn=" + mScreenOn);
             }
 
             /** clear the roaming state, if we were roaming, we failed */
@@ -7629,22 +7451,8 @@ public class WifiStateMachine extends StateMachine implements WifiNative.WifiRss
                         messageHandlingStatus = MESSAGE_HANDLING_STATUS_REFUSED;
                         return HANDLED;
                     }
-                    if (message.arg1 == SCAN_ALARM_SOURCE) {
-                        // Check if the CMD_START_SCAN message is obsolete (and thus if it should
-                        // not be processed) and restart the scan
-                        int period =
-                                mWifiConfigManager.mWifiDisconnectedShortScanIntervalMs.get();
-                        if (mP2pConnected.get()) {
-                            period = (int) mFacade.getLongSetting(mContext,
-                                    Settings.Global.WIFI_SCAN_INTERVAL_WHEN_P2P_CONNECTED_MS,
-                                    period);
-                        }
 
-                        handleScanRequest(message);
-                        ret = HANDLED;
-                    } else {
-                        ret = NOT_HANDLED;
-                    }
+                    ret = NOT_HANDLED;
                     break;
                 case WifiP2pServiceImpl.P2P_CONNECTION_CHANGED:
                     NetworkInfo info = (NetworkInfo) message.obj;