MediaMetrics: Add AudioAnalytics
Test: mediametrics dumpsys, atest mediametrics_tests
Bug: 138583596
Change-Id: I56c82e6c685a9fae21581f14d3b370a8e352f3f3
diff --git a/services/mediaanalytics/TimeMachine.h b/services/mediaanalytics/TimeMachine.h
new file mode 100644
index 0000000..578b838
--- /dev/null
+++ b/services/mediaanalytics/TimeMachine.h
@@ -0,0 +1,484 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <any>
+#include <map>
+#include <sstream>
+#include <string>
+#include <variant>
+#include <vector>
+
+#include <media/MediaAnalyticsItem.h>
+#include <utils/Timers.h>
+
+namespace android::mediametrics {
+
+// define a way of printing the monostate
+inline std::ostream & operator<< (std::ostream& s,
+ std::monostate const& v __unused) {
+ s << "none_item";
+ return s;
+}
+
+// define a way of printing a variant
+// see https://en.cppreference.com/w/cpp/utility/variant/visit
+template <typename T0, typename ... Ts>
+std::ostream & operator<< (std::ostream& s,
+ std::variant<T0, Ts...> const& v) {
+ std::visit([&s](auto && arg){ s << std::forward<decltype(arg)>(arg); }, v);
+ return s;
+}
+
+/**
+ * The TimeMachine is used to record timing changes of MediaAnalyticItem
+ * properties.
+ *
+ * Any URL that ends with '!' will have a time sequence that keeps duplicates.
+ *
+ * The TimeMachine is NOT thread safe.
+ */
+class TimeMachine {
+
+ using Elem = std::variant<std::monostate, int32_t, int64_t, double, std::string>;
+ using PropertyHistory = std::multimap<int64_t /* time */, Elem>;
+
+ // KeyHistory contains no lock.
+ // Access is through the TimeMachine, and a hash-striped lock is used
+ // before calling into KeyHistory.
+ class KeyHistory {
+ public:
+ template <typename T>
+ KeyHistory(T key, pid_t pid, uid_t uid, int64_t time)
+ : mKey(key)
+ , mPid(pid)
+ , mUid(uid)
+ , mCreationTime(time)
+ , mLastModificationTime(time)
+ {
+ putValue("_pid", (int32_t)pid, time);
+ putValue("_uid", (int32_t)uid, time);
+ }
+
+ status_t checkPermission(uid_t uidCheck) const {
+ return uidCheck != (uid_t)-1 && uidCheck != mUid ? PERMISSION_DENIED : NO_ERROR;
+ }
+
+ template <typename T>
+ status_t getValue(const std::string &property, T* value, int64_t time = 0) const {
+ if (time == 0) time = systemTime(SYSTEM_TIME_BOOTTIME);
+ const auto tsptr = mPropertyMap.find(property);
+ if (tsptr == mPropertyMap.end()) return BAD_VALUE;
+ const auto& timeSequence = tsptr->second;
+ auto eptr = timeSequence.upper_bound(time);
+ if (eptr == timeSequence.begin()) return BAD_VALUE;
+ --eptr;
+ if (eptr == timeSequence.end()) return BAD_VALUE;
+ const T* vptr = std::get_if<T>(&eptr->second);
+ if (vptr == nullptr) return BAD_VALUE;
+ *value = *vptr;
+ return NO_ERROR;
+ }
+
+ template <typename T>
+ status_t getValue(const std::string &property, T defaultValue, int64_t time = 0) const {
+ T value;
+ return getValue(property, &value, time) != NO_ERROR ? defaultValue : value;
+ }
+
+ void putProp(
+ const std::string &name, const MediaAnalyticsItem::Prop &prop, int64_t time = 0) {
+ prop.visit([&](auto value) { putValue(name, value, time); });
+ }
+
+ template <typename T>
+ void putValue(const std::string &property,
+ T&& e, int64_t time = 0) {
+ if (time == 0) time = systemTime(SYSTEM_TIME_BOOTTIME);
+ mLastModificationTime = time;
+ auto& timeSequence = mPropertyMap[property];
+ Elem el{std::forward<T>(e)};
+ if (timeSequence.empty() // no elements
+ || property.back() == '!' // keep duplicates TODO: remove?
+ || timeSequence.rbegin()->second != el) { // value changed
+ timeSequence.emplace(time, std::move(el));
+ }
+ }
+
+ // Explicitly ignore rate properties - we don't expose them for now.
+ void putValue(
+ const std::string &property __unused,
+ std::pair<int64_t, int64_t>& e __unused,
+ int64_t time __unused) {
+ }
+
+ std::pair<std::string, int32_t> dump(int32_t lines, int64_t time) const {
+ std::stringstream ss;
+ int32_t ll = lines;
+ for (auto& tsPair : mPropertyMap) {
+ if (ll <= 0) break;
+ ss << dump(mKey, tsPair, time);
+ --ll;
+ }
+ return { ss.str(), lines - ll };
+ }
+
+ int64_t getLastModificationTime() const { return mLastModificationTime; }
+
+ private:
+ static std::string dump(
+ const std::string &key,
+ const std::pair<std::string /* prop */, PropertyHistory>& tsPair,
+ int64_t time) {
+ const auto timeSequence = tsPair.second;
+ auto eptr = timeSequence.lower_bound(time);
+ if (eptr == timeSequence.end()) {
+ return tsPair.first + "={};\n";
+ }
+ std::stringstream ss;
+ ss << key << "." << tsPair.first << "={";
+ do {
+ ss << eptr->first << ":" << eptr->second << ",";
+ } while (++eptr != timeSequence.end());
+ ss << "};\n";
+ return ss.str();
+ }
+
+ const std::string mKey;
+ const pid_t mPid __unused;
+ const uid_t mUid;
+ const int64_t mCreationTime __unused;
+
+ int64_t mLastModificationTime;
+ std::map<std::string /* property */, PropertyHistory> mPropertyMap;
+ };
+
+ using History = std::map<std::string /* key */, std::shared_ptr<KeyHistory>>;
+
+ static inline constexpr size_t kKeyLowWaterMark = 500;
+ static inline constexpr size_t kKeyHighWaterMark = 1000;
+
+ // Estimated max data space usage is 3KB * kKeyHighWaterMark.
+
+public:
+
+ TimeMachine() = default;
+ TimeMachine(size_t keyLowWaterMark, size_t keyHighWaterMark)
+ : mKeyLowWaterMark(keyLowWaterMark)
+ , mKeyHighWaterMark(keyHighWaterMark) {
+ LOG_ALWAYS_FATAL_IF(keyHighWaterMark <= keyLowWaterMark,
+ "%s: required that keyHighWaterMark:%zu > keyLowWaterMark:%zu",
+ __func__, keyHighWaterMark, keyLowWaterMark);
+ }
+
+ /**
+ * Put all the properties from an item into the Time Machine log.
+ */
+ status_t put(const std::shared_ptr<const MediaAnalyticsItem>& item, bool isTrusted = false) {
+ const int64_t time = item->getTimestamp();
+ const std::string &key = item->getKey();
+
+ std::shared_ptr<KeyHistory> keyHistory;
+ {
+ std::vector<std::any> garbage;
+ std::lock_guard lock(mLock);
+
+ auto it = mHistory.find(key);
+ if (it == mHistory.end()) {
+ if (!isTrusted) return PERMISSION_DENIED;
+
+ (void)gc_l(garbage);
+
+ // no keylock needed here as we are sole owner
+ // until placed on mHistory.
+ keyHistory = std::make_shared<KeyHistory>(
+ key, item->getPid(), item->getUid(), time);
+ mHistory[key] = keyHistory;
+ } else {
+ keyHistory = it->second;
+ }
+ }
+
+ // deferred contains remote properties (for other keys) to do later.
+ std::vector<const MediaAnalyticsItem::Prop *> deferred;
+ {
+ // handle local properties
+ std::lock_guard lock(getLockForKey(key));
+ if (!isTrusted) {
+ status_t status = keyHistory->checkPermission(item->getUid());
+ if (status != NO_ERROR) return status;
+ }
+
+ for (const auto &prop : *item) {
+ const std::string &name = prop.getName();
+ if (name.size() == 0 || name[0] == '_') continue;
+
+ // Cross key settings are with [key]property
+ if (name[0] == '[') {
+ if (!isTrusted) continue;
+ deferred.push_back(&prop);
+ } else {
+ keyHistory->putProp(name, prop, time);
+ }
+ }
+ }
+
+ // handle remote properties, if any
+ for (const auto propptr : deferred) {
+ const auto &prop = *propptr;
+ const std::string &name = prop.getName();
+ size_t end = name.find_first_of(']'); // TODO: handle nested [] or escape?
+ if (end == 0) continue;
+ std::string remoteKey = name.substr(1, end - 1);
+ std::string remoteName = name.substr(end + 1);
+ if (remoteKey.size() == 0 || remoteName.size() == 0) continue;
+ std::shared_ptr<KeyHistory> remoteKeyHistory;
+ {
+ std::lock_guard lock(mLock);
+ auto it = mHistory.find(remoteKey);
+ if (it == mHistory.end()) continue;
+ remoteKeyHistory = it->second;
+ }
+ std::lock_guard(getLockForKey(remoteKey));
+ remoteKeyHistory->putProp(remoteName, prop, time);
+ }
+ return NO_ERROR;
+ }
+
+ template <typename T>
+ status_t get(const std::string &key, const std::string &property,
+ T* value, int32_t uidCheck = -1, int64_t time = 0) const {
+ std::shared_ptr<KeyHistory> keyHistory;
+ {
+ std::lock_guard lock(mLock);
+ const auto it = mHistory.find(key);
+ if (it == mHistory.end()) return BAD_VALUE;
+ keyHistory = it->second;
+ }
+ std::lock_guard lock(getLockForKey(key));
+ return keyHistory->checkPermission(uidCheck)
+ ?: keyHistory->getValue(property, value, time);
+ }
+
+ /**
+ * Individual property put.
+ *
+ * Put takes in a time (if none is provided then BOOTTIME is used).
+ */
+ template <typename T>
+ status_t put(const std::string &url, T &&e, int64_t time = 0) {
+ std::string key;
+ std::string prop;
+ std::shared_ptr<KeyHistory> keyHistory =
+ getKeyHistoryFromUrl(url, &key, &prop);
+ if (keyHistory == nullptr) return BAD_VALUE;
+ if (time == 0) time = systemTime(SYSTEM_TIME_BOOTTIME);
+ std::lock_guard lock(getLockForKey(key));
+ keyHistory->putValue(prop, std::forward<T>(e), time);
+ return NO_ERROR;
+ }
+
+ /**
+ * Individual property get
+ */
+ template <typename T>
+ status_t get(const std::string &url, T* value, int32_t uidCheck, int64_t time = 0) const {
+ std::string key;
+ std::string prop;
+ std::shared_ptr<KeyHistory> keyHistory =
+ getKeyHistoryFromUrl(url, &key, &prop);
+ if (keyHistory == nullptr) return BAD_VALUE;
+
+ std::lock_guard lock(getLockForKey(key));
+ return keyHistory->checkPermission(uidCheck)
+ ?: keyHistory->getValue(prop, value, time);
+ }
+
+ /**
+ * Individual property get with default
+ */
+ template <typename T>
+ T get(const std::string &url, const T &defaultValue, int32_t uidCheck,
+ int64_t time = 0) const {
+ T value;
+ return get(url, &value, uidCheck, time) == NO_ERROR
+ ? value : defaultValue;
+ }
+
+ /**
+ * Returns number of keys in the Time Machine.
+ */
+ size_t size() const {
+ std::lock_guard lock(mLock);
+ return mHistory.size();
+ }
+
+ /**
+ * Clears all properties from the Time Machine.
+ */
+ void clear() {
+ std::lock_guard lock(mLock);
+ mHistory.clear();
+ }
+
+ /**
+ * Returns a pair consisting of the TimeMachine state as a string
+ * and the number of lines in the string.
+ *
+ * The number of lines in the returned pair is used as an optimization
+ * for subsequent line limiting.
+ *
+ * \param lines the maximum number of lines in the string returned.
+ * \param key selects only that key.
+ * \param time to start the dump from.
+ */
+ std::pair<std::string, int32_t> dump(
+ int32_t lines = INT32_MAX, const std::string &key = {}, int64_t time = 0) const {
+ std::lock_guard lock(mLock);
+ if (!key.empty()) { // use std::regex
+ const auto it = mHistory.find(key);
+ if (it == mHistory.end()) return {};
+ std::lock_guard lock(getLockForKey(it->first));
+ return it->second->dump(lines, time);
+ }
+
+ std::stringstream ss;
+ int32_t ll = lines;
+ for (const auto &keyPair : mHistory) {
+ std::lock_guard lock(getLockForKey(keyPair.first));
+ if (lines <= 0) break;
+ auto [s, l] = keyPair.second->dump(ll, time);
+ ss << s;
+ ll -= l;
+ }
+ return { ss.str(), lines - ll };
+ }
+
+private:
+
+ // Obtains the lock for a KeyHistory.
+ std::mutex &getLockForKey(const std::string &key) const {
+ return mKeyLocks[std::hash<std::string>{}(key) % std::size(mKeyLocks)];
+ }
+
+ // Finds a KeyHistory from a URL. Returns nullptr if not found.
+ std::shared_ptr<KeyHistory> getKeyHistoryFromUrl(
+ std::string url, std::string* key, std::string *prop) const {
+ std::lock_guard lock(mLock);
+
+ auto it = mHistory.upper_bound(url);
+ if (it == mHistory.begin()) {
+ return nullptr;
+ }
+ --it; // go to the actual key, if it exists.
+
+ const std::string& itKey = it->first;
+ if (strncmp(itKey.c_str(), url.c_str(), itKey.size())) {
+ return nullptr;
+ }
+ if (key) *key = itKey;
+ if (prop) *prop = url.substr(itKey.size() + 1);
+ return it->second;
+ }
+
+ // GUARDED_BY mLock
+ /**
+ * Garbage collects if the TimeMachine size exceeds the high water mark.
+ *
+ * \param garbage a type-erased vector of elements to be destroyed
+ * outside of lock. Move large items to be destroyed here.
+ *
+ * \return true if garbage collection was done.
+ */
+ bool gc_l(std::vector<std::any>& garbage) {
+ // TODO: something better than this for garbage collection.
+ if (mHistory.size() < mKeyHighWaterMark) return false;
+
+ ALOGD("%s: garbage collection", __func__);
+
+ // erase everything explicitly expired.
+ std::multimap<int64_t, std::string> accessList;
+ // use a stale vector with precise type to avoid type erasure overhead in garbage
+ std::vector<std::shared_ptr<KeyHistory>> stale;
+
+ for (auto it = mHistory.begin(); it != mHistory.end();) {
+ const std::string& key = it->first;
+ std::shared_ptr<KeyHistory> &keyHist = it->second;
+
+ std::lock_guard lock(getLockForKey(it->first));
+ int64_t expireTime = keyHist->getValue("_expire", -1 /* default */);
+ if (expireTime != -1) {
+ stale.emplace_back(std::move(it->second));
+ it = mHistory.erase(it);
+ } else {
+ accessList.emplace(keyHist->getLastModificationTime(), key);
+ ++it;
+ }
+ }
+
+ if (mHistory.size() > mKeyLowWaterMark) {
+ const size_t toDelete = mHistory.size() - mKeyLowWaterMark;
+ auto it = accessList.begin();
+ for (size_t i = 0; i < toDelete; ++i) {
+ auto it2 = mHistory.find(it->second);
+ stale.emplace_back(std::move(it2->second));
+ mHistory.erase(it2);
+ ++it;
+ }
+ }
+ garbage.emplace_back(std::move(accessList));
+ garbage.emplace_back(std::move(stale));
+
+ ALOGD("%s(%zu, %zu): key size:%zu",
+ __func__, mKeyLowWaterMark, mKeyHighWaterMark,
+ mHistory.size());
+ return true;
+ }
+
+ const size_t mKeyLowWaterMark = kKeyLowWaterMark;
+ const size_t mKeyHighWaterMark = kKeyHighWaterMark;
+
+ /**
+ * Locking Strategy
+ *
+ * Each key in the History has a KeyHistory. To get a shared pointer to
+ * the KeyHistory requires a lookup of mHistory under mLock. Once the shared
+ * pointer to KeyHistory is obtained, the mLock for mHistory can be released.
+ *
+ * Once the shared pointer to the key's KeyHistory is obtained, the KeyHistory
+ * can be locked for read and modification through the method getLockForKey().
+ *
+ * Instead of having a mutex per KeyHistory, we use a hash striped lock
+ * which assigns a mutex based on the hash of the key string.
+ *
+ * Once the last shared pointer reference to KeyHistory is released, it is
+ * destroyed. This is done through the garbage collection method.
+ *
+ * This two level locking allows multiple threads to access the TimeMachine
+ * in parallel.
+ */
+
+ mutable std::mutex mLock; // Lock for mHistory
+ History mHistory; // GUARDED_BY mLock
+
+ // KEY_LOCKS is the number of mutexes for keys.
+ // It need not be a power of 2, but faster that way.
+ static inline constexpr size_t KEY_LOCKS = 256;
+ mutable std::mutex mKeyLocks[KEY_LOCKS]; // Hash-striped lock for KeyHistory based on key.
+};
+
+} // namespace android::mediametrics