1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #define DEBUG false // STOPSHIP if true
18 #include "Log.h"
19
20 #include "DurationAnomalyTracker.h"
21 #include "guardrail/StatsdStats.h"
22
23 namespace android {
24 namespace os {
25 namespace statsd {
26
DurationAnomalyTracker(const Alert & alert,const ConfigKey & configKey,const sp<AlarmMonitor> & alarmMonitor)27 DurationAnomalyTracker::DurationAnomalyTracker(const Alert& alert, const ConfigKey& configKey,
28 const sp<AlarmMonitor>& alarmMonitor)
29 : AnomalyTracker(alert, configKey), mAlarmMonitor(alarmMonitor) {
30 VLOG("DurationAnomalyTracker() called");
31 }
32
~DurationAnomalyTracker()33 DurationAnomalyTracker::~DurationAnomalyTracker() {
34 VLOG("~DurationAnomalyTracker() called");
35 cancelAllAlarms();
36 }
37
startAlarm(const MetricDimensionKey & dimensionKey,const int64_t & timestampNs)38 void DurationAnomalyTracker::startAlarm(const MetricDimensionKey& dimensionKey,
39 const int64_t& timestampNs) {
40 // Alarms are stored in secs. Must round up, since if it fires early, it is ignored completely.
41 uint32_t timestampSec = static_cast<uint32_t>((timestampNs -1) / NS_PER_SEC) + 1; // round up
42 if (isInRefractoryPeriod(timestampNs, dimensionKey)) {
43 VLOG("Not setting anomaly alarm since it would fall in the refractory period.");
44 return;
45 }
46
47 auto itr = mAlarms.find(dimensionKey);
48 if (itr != mAlarms.end() && mAlarmMonitor != nullptr) {
49 mAlarmMonitor->remove(itr->second);
50 }
51
52 sp<const InternalAlarm> alarm = new InternalAlarm{timestampSec};
53 mAlarms[dimensionKey] = alarm;
54 if (mAlarmMonitor != nullptr) {
55 mAlarmMonitor->add(alarm);
56 }
57 }
58
stopAlarm(const MetricDimensionKey & dimensionKey,const int64_t & timestampNs)59 void DurationAnomalyTracker::stopAlarm(const MetricDimensionKey& dimensionKey,
60 const int64_t& timestampNs) {
61 const auto itr = mAlarms.find(dimensionKey);
62 if (itr == mAlarms.end()) {
63 return;
64 }
65
66 // If the alarm is set in the past but hasn't fired yet (due to lag), catch it now.
67 if (itr->second != nullptr && timestampNs >= (int64_t)NS_PER_SEC * itr->second->timestampSec) {
68 declareAnomaly(timestampNs, mAlert.metric_id(), dimensionKey,
69 mAlert.trigger_if_sum_gt() + (timestampNs / NS_PER_SEC) -
70 itr->second->timestampSec);
71 }
72 if (mAlarmMonitor != nullptr) {
73 mAlarmMonitor->remove(itr->second);
74 }
75 mAlarms.erase(dimensionKey);
76 }
77
cancelAllAlarms()78 void DurationAnomalyTracker::cancelAllAlarms() {
79 if (mAlarmMonitor != nullptr) {
80 for (const auto& itr : mAlarms) {
81 mAlarmMonitor->remove(itr.second);
82 }
83 }
84 mAlarms.clear();
85 }
86
informAlarmsFired(const int64_t & timestampNs,unordered_set<sp<const InternalAlarm>,SpHash<InternalAlarm>> & firedAlarms)87 void DurationAnomalyTracker::informAlarmsFired(const int64_t& timestampNs,
88 unordered_set<sp<const InternalAlarm>, SpHash<InternalAlarm>>& firedAlarms) {
89
90 if (firedAlarms.empty() || mAlarms.empty()) return;
91 // Find the intersection of firedAlarms and mAlarms.
92 // The for loop is inefficient, since it loops over all keys, but that's okay since it is very
93 // seldomly called. The alternative would be having InternalAlarms store information about the
94 // DurationAnomalyTracker and key, but that's a lot of data overhead to speed up something that
95 // is rarely ever called.
96 unordered_map<MetricDimensionKey, sp<const InternalAlarm>> matchedAlarms;
97 for (const auto& kv : mAlarms) {
98 if (firedAlarms.count(kv.second) > 0) {
99 matchedAlarms.insert({kv.first, kv.second});
100 }
101 }
102
103 // Now declare each of these alarms to have fired.
104 for (const auto& kv : matchedAlarms) {
105 declareAnomaly(
106 timestampNs, mAlert.metric_id(), kv.first,
107 mAlert.trigger_if_sum_gt() + (timestampNs / NS_PER_SEC) - kv.second->timestampSec);
108 mAlarms.erase(kv.first);
109 firedAlarms.erase(kv.second); // No one else can also own it, so we're done with it.
110 }
111 }
112
113 } // namespace statsd
114 } // namespace os
115 } // namespace android
116