Anomaly detection statsdstats

Adds statsdstats for tracking the number of anomaly alarms registered.

Test: adb shell data/nativetest64/statsd_test/statsd_test
Bug: 67978682
Change-Id: I4aa0539a13c60ccb3b7fd2a4f41c4ad867f3a4ea
diff --git a/cmds/statsd/src/StatsService.cpp b/cmds/statsd/src/StatsService.cpp
index fa7fe0c..dc12efb 100644
--- a/cmds/statsd/src/StatsService.cpp
+++ b/cmds/statsd/src/StatsService.cpp
@@ -72,7 +72,7 @@
 
 // ======================================================================
 StatsService::StatsService(const sp<Looper>& handlerLooper)
-    : mAnomalyMonitor(new AnomalyMonitor(2))  // TODO: Put this comment somewhere better
+    : mAnomalyMonitor(new AnomalyMonitor(MIN_DIFF_TO_UPDATE_REGISTERED_ALARM_SECS))
 {
     mUidMap = new UidMap();
     mConfigManager = new ConfigManager();
diff --git a/cmds/statsd/src/StatsService.h b/cmds/statsd/src/StatsService.h
index bdae1ef..e434f65 100644
--- a/cmds/statsd/src/StatsService.h
+++ b/cmds/statsd/src/StatsService.h
@@ -46,6 +46,10 @@
     StatsService(const sp<Looper>& handlerLooper);
     virtual ~StatsService();
 
+    /** The anomaly alarm registered with AlarmManager won't be updated by less than this. */
+    // TODO: Consider making this configurable. And choose a good number.
+    const uint32_t MIN_DIFF_TO_UPDATE_REGISTERED_ALARM_SECS = 5;
+
     virtual status_t onTransact(uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags);
     virtual status_t dump(int fd, const Vector<String16>& args);
     virtual status_t command(FILE* in, FILE* out, FILE* err, Vector<String8>& args);
diff --git a/cmds/statsd/src/anomaly/AnomalyMonitor.cpp b/cmds/statsd/src/anomaly/AnomalyMonitor.cpp
index 2b2bcfc..4912648 100644
--- a/cmds/statsd/src/anomaly/AnomalyMonitor.cpp
+++ b/cmds/statsd/src/anomaly/AnomalyMonitor.cpp
@@ -18,6 +18,7 @@
 #include "Log.h"
 
 #include "anomaly/AnomalyMonitor.h"
+#include "guardrail/StatsdStats.h"
 
 namespace android {
 namespace os {
@@ -76,10 +77,7 @@
     if (!wasPresent) return;
     if (mPq.empty()) {
         if (DEBUG) ALOGD("Queue is empty. Cancel any alarm.");
-        mRegisteredAlarmTimeSec = 0;
-        if (mStatsCompanionService != nullptr) {
-            mStatsCompanionService->cancelAnomalyAlarm();
-        }
+        cancelRegisteredAlarmTime_l();
         return;
     }
     uint32_t soonestAlarmTimeSec = mPq.top()->timestampSec;
@@ -106,10 +104,7 @@
     if (!oldAlarms.empty()) {
         if (mPq.empty()) {
             if (DEBUG) ALOGD("Queue is empty. Cancel any alarm.");
-            mRegisteredAlarmTimeSec = 0;
-            if (mStatsCompanionService != nullptr) {
-                mStatsCompanionService->cancelAnomalyAlarm();
-            }
+            cancelRegisteredAlarmTime_l();
         } else {
             // Always update the registered alarm in this case (unlike remove()).
             updateRegisteredAlarmTime_l(mPq.top()->timestampSec);
@@ -123,6 +118,16 @@
     mRegisteredAlarmTimeSec = timestampSec;
     if (mStatsCompanionService != nullptr) {
         mStatsCompanionService->setAnomalyAlarm(secToMs(mRegisteredAlarmTimeSec));
+        StatsdStats::getInstance().noteRegisteredAnomalyAlarmChanged();
+    }
+}
+
+void AnomalyMonitor::cancelRegisteredAlarmTime_l() {
+    if (DEBUG) ALOGD("Cancelling reg alarm.");
+    mRegisteredAlarmTimeSec = 0;
+    if (mStatsCompanionService != nullptr) {
+        mStatsCompanionService->cancelAnomalyAlarm();
+        StatsdStats::getInstance().noteRegisteredAnomalyAlarmChanged();
     }
 }
 
diff --git a/cmds/statsd/src/anomaly/AnomalyMonitor.h b/cmds/statsd/src/anomaly/AnomalyMonitor.h
index e19c469..7acc7904 100644
--- a/cmds/statsd/src/anomaly/AnomalyMonitor.h
+++ b/cmds/statsd/src/anomaly/AnomalyMonitor.h
@@ -138,6 +138,12 @@
      */
     void updateRegisteredAlarmTime_l(uint32_t timestampSec);
 
+    /**
+     * Cancels the alarm registered with StatsCompanionService.
+     * Also correspondingly sets mRegisteredAlarmTimeSec to 0.
+     */
+    void cancelRegisteredAlarmTime_l();
+
     /** Converts uint32 timestamp in seconds to a Java long in msec. */
     int64_t secToMs(uint32_t timeSec);
 };
diff --git a/cmds/statsd/src/guardrail/StatsdStats.cpp b/cmds/statsd/src/guardrail/StatsdStats.cpp
index 2957457..a48ebc3 100644
--- a/cmds/statsd/src/guardrail/StatsdStats.cpp
+++ b/cmds/statsd/src/guardrail/StatsdStats.cpp
@@ -46,6 +46,7 @@
 const int FIELD_ID_METRIC_STATS = 6;
 const int FIELD_ID_ATOM_STATS = 7;
 const int FIELD_ID_UIDMAP_STATS = 8;
+const int FIELD_ID_ANOMALY_ALARM_STATS = 9;
 
 const int FIELD_ID_MATCHER_STATS_NAME = 1;
 const int FIELD_ID_MATCHER_STATS_COUNT = 2;
@@ -59,6 +60,8 @@
 const int FIELD_ID_ATOM_STATS_TAG = 1;
 const int FIELD_ID_ATOM_STATS_COUNT = 2;
 
+const int FIELD_ID_ANOMALY_ALARMS_REGISTERED = 1;
+
 // TODO: add stats for pulled atoms.
 StatsdStats::StatsdStats() {
     mPushedAtomStats.resize(android::util::kMaxPushedAtomId + 1);
@@ -219,6 +222,11 @@
     matcherStats[name]++;
 }
 
+void StatsdStats::noteRegisteredAnomalyAlarmChanged() {
+    lock_guard<std::mutex> lock(mLock);
+    mAnomalyAlarmRegisteredStats++;
+}
+
 void StatsdStats::noteAtomLogged(int atomId, int32_t timeSec) {
     lock_guard<std::mutex> lock(mLock);
 
@@ -246,6 +254,7 @@
     mConditionStats.clear();
     mMetricsStats.clear();
     std::fill(mPushedAtomStats.begin(), mPushedAtomStats.end(), 0);
+    mAnomalyAlarmRegisteredStats = 0;
     mMatcherStats.clear();
     for (auto& config : mConfigStats) {
         config.second.clear_broadcast_sent_time_sec();
@@ -386,6 +395,15 @@
         }
     }
 
+    if (mAnomalyAlarmRegisteredStats > 0) {
+        VLOG("********AnomalyAlarmStats stats***********");
+        long long token = proto.start(FIELD_TYPE_MESSAGE | FIELD_ID_ANOMALY_ALARM_STATS);
+        proto.write(FIELD_TYPE_INT32 | FIELD_ID_ANOMALY_ALARMS_REGISTERED,
+                    mAnomalyAlarmRegisteredStats);
+        proto.end(token);
+        VLOG("Anomaly alarm registrations: %d", mAnomalyAlarmRegisteredStats);
+    }
+
     const int numBytes = mUidMapStats.ByteSize();
     vector<char> buffer(numBytes);
     mUidMapStats.SerializeToArray(&buffer[0], numBytes);
diff --git a/cmds/statsd/src/guardrail/StatsdStats.h b/cmds/statsd/src/guardrail/StatsdStats.h
index d6f6566..95a4e26 100644
--- a/cmds/statsd/src/guardrail/StatsdStats.h
+++ b/cmds/statsd/src/guardrail/StatsdStats.h
@@ -117,6 +117,11 @@
     void noteAtomLogged(int atomId, int32_t timeSec);
 
     /**
+     * Report that statsd modified the anomaly alarm registered with StatsCompanionService.
+     */
+    void noteRegisteredAnomalyAlarmChanged();
+
+    /**
      * Records the number of snapshot and delta entries that are being dropped from the uid map.
      */
     void noteUidMapDropped(int snapshots, int deltas);
@@ -174,6 +179,10 @@
     // This is a vector, not a map because it will be accessed A LOT -- for each stats log.
     std::vector<int> mPushedAtomStats;
 
+    // Stores the number of times statsd modified the anomaly alarm registered with
+    // StatsCompanionService.
+    int mAnomalyAlarmRegisteredStats = 0;
+
     // Stores how many times a matcher have been matched.
     std::map<const ConfigKey, std::map<const std::string, int>> mMatcherStats;
 
@@ -195,6 +204,7 @@
     FRIEND_TEST(StatsdStatsTest, TestSubStats);
     FRIEND_TEST(StatsdStatsTest, TestAtomLog);
     FRIEND_TEST(StatsdStatsTest, TestTimestampThreshold);
+    FRIEND_TEST(StatsdStatsTest, TestAnomalyMonitor);
 };
 
 }  // namespace statsd
diff --git a/cmds/statsd/src/stats_log.proto b/cmds/statsd/src/stats_log.proto
index 60d9a3d..79c4727 100644
--- a/cmds/statsd/src/stats_log.proto
+++ b/cmds/statsd/src/stats_log.proto
@@ -229,4 +229,9 @@
         optional int32 dropped_changes = 5;
     }
     optional UidMapStats uidmap_stats = 8;
+
+    message AnomalyAlarmStats {
+        optional int32 alarms_registered = 1;
+    }
+    optional AnomalyAlarmStats anomaly_alarm_stats = 9;
 }
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