Revert "Revert "[TimeStats] Add callback for global stats""

This reverts commit de64c56f39b03f4908200d1ed2fdc9561f86fe2a.

Reason for revert: Rolling forward with fix

Test: adb shell cmd stats pull-source 10062
Change-Id: I981b12a1c5e69aad0c0d3a409d8b90b3399401f4
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 1796476..06a9b1f 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -494,6 +494,7 @@
     ALOGI("Boot is finished (%ld ms)", long(ns2ms(duration)) );
 
     mFrameTracer->initialize();
+    mTimeStats->onBootFinished();
 
     // wait patiently for the window manager death
     const String16 name("window");
diff --git a/services/surfaceflinger/TimeStats/Android.bp b/services/surfaceflinger/TimeStats/Android.bp
index 20c2218..7ff2594 100644
--- a/services/surfaceflinger/TimeStats/Android.bp
+++ b/services/surfaceflinger/TimeStats/Android.bp
@@ -8,12 +8,18 @@
         "libcutils",
         "liblog",
         "libprotobuf-cpp-lite",
+        "libstatslog",
+        "libstatspull",
+        "libstatssocket",
         "libtimestats_proto",
         "libui",
         "libutils",
     ],
     export_include_dirs: ["."],
     export_shared_lib_headers: [
+        "libstatslog",
+        "libstatspull",
+        "libstatssocket",
         "libtimestats_proto",
     ],
     cppflags: [
diff --git a/services/surfaceflinger/TimeStats/TimeStats.cpp b/services/surfaceflinger/TimeStats/TimeStats.cpp
index 0939fa4..44a59fd 100644
--- a/services/surfaceflinger/TimeStats/TimeStats.cpp
+++ b/services/surfaceflinger/TimeStats/TimeStats.cpp
@@ -36,11 +36,50 @@
 
 namespace impl {
 
-TimeStats::TimeStats() {
+status_pull_atom_return_t TimeStats::pullGlobalAtomCallback(int32_t atom_tag,
+                                                            pulled_stats_event_list* data,
+                                                            void* cookie) {
+    impl::TimeStats* timeStats = reinterpret_cast<impl::TimeStats*>(cookie);
+    if (atom_tag != android::util::SURFACEFLINGER_STATS_GLOBAL_INFO) {
+        return STATS_PULL_SKIP;
+    }
+
+    std::lock_guard<std::mutex> lock(timeStats->mMutex);
+
+    const auto& stats = timeStats->mTimeStats;
+    if (stats.statsStart == 0) {
+        return STATS_PULL_SKIP;
+    }
+    timeStats->flushPowerTimeLocked();
+
+    struct stats_event* event = timeStats->mStatsDelegate->addStatsEventToPullData(data);
+    timeStats->mStatsDelegate->statsEventSetAtomId(event,
+                                                   android::util::SURFACEFLINGER_STATS_GLOBAL_INFO);
+    timeStats->mStatsDelegate->statsEventWriteInt64(event, stats.totalFrames);
+    timeStats->mStatsDelegate->statsEventWriteInt64(event, stats.missedFrames);
+    timeStats->mStatsDelegate->statsEventWriteInt64(event, stats.clientCompositionFrames);
+    timeStats->mStatsDelegate->statsEventWriteInt64(event, stats.displayOnTime);
+    timeStats->mStatsDelegate->statsEventWriteInt64(event, stats.presentToPresent.totalTime());
+    timeStats->mStatsDelegate->statsEventBuild(event);
+    timeStats->clearGlobalLocked();
+
+    return STATS_PULL_SUCCESS;
+}
+
+TimeStats::TimeStats() : TimeStats(nullptr) {}
+
+TimeStats::TimeStats(std::unique_ptr<StatsEventDelegate> statsDelegate) {
+    if (statsDelegate != nullptr) {
+        mStatsDelegate = std::move(statsDelegate);
+    }
+}
+
+void TimeStats::onBootFinished() {
     // Temporarily enable TimeStats by default. Telemetry is disabled while
     // we move onto statsd, so TimeStats is currently not exercised at all
-    // during testing.
-    // TODO: remove this.
+    // during testing without enabling by default.
+    // TODO: remove this, as we should only be paying this overhead on devices
+    // where statsd exists.
     enable();
 }
 
@@ -69,7 +108,7 @@
     }
 
     if (argsMap.count("-clear")) {
-        clear();
+        clearAll();
     }
 
     if (argsMap.count("-enable")) {
@@ -594,6 +633,8 @@
     mEnabled.store(true);
     mTimeStats.statsStart = static_cast<int64_t>(std::time(0));
     mPowerTime.prevTime = systemTime();
+    mStatsDelegate->registerStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO,
+                                                  TimeStats::pullGlobalAtomCallback, nullptr, this);
     ALOGD("Enabled");
 }
 
@@ -606,15 +647,20 @@
     flushPowerTimeLocked();
     mEnabled.store(false);
     mTimeStats.statsEnd = static_cast<int64_t>(std::time(0));
+    mStatsDelegate->unregisterStatsPullAtomCallback(
+            android::util::SURFACEFLINGER_STATS_GLOBAL_INFO);
     ALOGD("Disabled");
 }
 
-void TimeStats::clear() {
+void TimeStats::clearAll() {
+    std::lock_guard<std::mutex> lock(mMutex);
+    clearGlobalLocked();
+    clearLayersLocked();
+}
+
+void TimeStats::clearGlobalLocked() {
     ATRACE_CALL();
 
-    std::lock_guard<std::mutex> lock(mMutex);
-    mTimeStatsTracker.clear();
-    mTimeStats.stats.clear();
     mTimeStats.statsStart = (mEnabled.load() ? static_cast<int64_t>(std::time(0)) : 0);
     mTimeStats.statsEnd = 0;
     mTimeStats.totalFrames = 0;
@@ -628,7 +674,15 @@
     mPowerTime.prevTime = systemTime();
     mGlobalRecord.prevPresentTime = 0;
     mGlobalRecord.presentFences.clear();
-    ALOGD("Cleared");
+    ALOGD("Cleared global stats");
+}
+
+void TimeStats::clearLayersLocked() {
+    ATRACE_CALL();
+
+    mTimeStatsTracker.clear();
+    mTimeStats.stats.clear();
+    ALOGD("Cleared layer stats");
 }
 
 bool TimeStats::isEnabled() {
diff --git a/services/surfaceflinger/TimeStats/TimeStats.h b/services/surfaceflinger/TimeStats/TimeStats.h
index 65e5cf4..5cd421c 100644
--- a/services/surfaceflinger/TimeStats/TimeStats.h
+++ b/services/surfaceflinger/TimeStats/TimeStats.h
@@ -17,6 +17,9 @@
 #pragma once
 
 #include <hardware/hwcomposer_defs.h>
+#include <stats_event.h>
+#include <stats_pull_atom_callback.h>
+#include <statslog.h>
 #include <timestatsproto/TimeStatsHelper.h>
 #include <timestatsproto/TimeStatsProtoHeader.h>
 #include <ui/FenceTime.h>
@@ -37,6 +40,10 @@
 public:
     virtual ~TimeStats() = default;
 
+    // Called once boot has been finished to perform additional capabilities,
+    // e.g. registration to statsd.
+    virtual void onBootFinished() = 0;
+
     virtual void parseArgs(bool asProto, const Vector<String16>& args, std::string& result) = 0;
     virtual bool isEnabled() = 0;
     virtual std::string miniDump() = 0;
@@ -131,6 +138,39 @@
 public:
     TimeStats();
 
+    // Delegate to the statsd service and associated APIs.
+    // Production code may use this class directly, whereas unit test may define
+    // a subclass for ease of testing.
+    class StatsEventDelegate {
+    public:
+        virtual ~StatsEventDelegate() = default;
+        virtual struct stats_event* addStatsEventToPullData(pulled_stats_event_list* data) {
+            return add_stats_event_to_pull_data(data);
+        }
+        virtual void registerStatsPullAtomCallback(int32_t atom_tag,
+                                                   stats_pull_atom_callback_t callback,
+                                                   pull_atom_metadata* metadata, void* cookie) {
+            return register_stats_pull_atom_callback(atom_tag, callback, metadata, cookie);
+        }
+
+        virtual void unregisterStatsPullAtomCallback(int32_t atom_tag) {
+            return unregister_stats_pull_atom_callback(atom_tag);
+        }
+
+        virtual void statsEventSetAtomId(struct stats_event* event, uint32_t atom_id) {
+            return stats_event_set_atom_id(event, atom_id);
+        }
+
+        virtual void statsEventWriteInt64(struct stats_event* event, int64_t field) {
+            return stats_event_write_int64(event, field);
+        }
+
+        virtual void statsEventBuild(struct stats_event* event) { return stats_event_build(event); }
+    };
+    // For testing only for injecting custom dependencies.
+    TimeStats(std::unique_ptr<StatsEventDelegate> statsDelegate);
+
+    void onBootFinished() override;
     void parseArgs(bool asProto, const Vector<String16>& args, std::string& result) override;
     bool isEnabled() override;
     std::string miniDump() override;
@@ -167,6 +207,9 @@
     static const size_t MAX_NUM_TIME_RECORDS = 64;
 
 private:
+    static status_pull_atom_return_t pullGlobalAtomCallback(int32_t atom_tag,
+                                                            pulled_stats_event_list* data,
+                                                            void* cookie);
     bool recordReadyLocked(int32_t layerId, TimeRecord* timeRecord);
     void flushAvailableRecordsToStatsLocked(int32_t layerId);
     void flushPowerTimeLocked();
@@ -174,7 +217,9 @@
 
     void enable();
     void disable();
-    void clear();
+    void clearAll();
+    void clearGlobalLocked();
+    void clearLayersLocked();
     void dump(bool asProto, std::optional<uint32_t> maxLayers, std::string& result);
 
     std::atomic<bool> mEnabled = false;
@@ -187,6 +232,7 @@
 
     static const size_t MAX_NUM_LAYER_RECORDS = 200;
     static const size_t MAX_NUM_LAYER_STATS = 200;
+    std::unique_ptr<StatsEventDelegate> mStatsDelegate = std::make_unique<StatsEventDelegate>();
 };
 
 } // namespace impl
diff --git a/services/surfaceflinger/tests/unittests/Android.bp b/services/surfaceflinger/tests/unittests/Android.bp
index becf484..e500672 100644
--- a/services/surfaceflinger/tests/unittests/Android.bp
+++ b/services/surfaceflinger/tests/unittests/Android.bp
@@ -83,6 +83,7 @@
         "perfetto_trace_protos",
     ],
     shared_libs: [
+        "libstatssocket",
         "libsurfaceflinger",
         "libtimestats",
         "libtimestats_proto",
diff --git a/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp b/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
index bcf3ba8..c667080 100644
--- a/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
+++ b/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
@@ -40,7 +40,9 @@
 namespace android {
 namespace {
 
+using testing::_;
 using testing::Contains;
+using testing::InSequence;
 using testing::SizeIs;
 using testing::UnorderedElementsAre;
 
@@ -136,7 +138,40 @@
     }
 
     std::mt19937 mRandomEngine = std::mt19937(std::random_device()());
-    std::unique_ptr<TimeStats> mTimeStats = std::make_unique<impl::TimeStats>();
+
+    class FakeStatsEventDelegate : public impl::TimeStats::StatsEventDelegate {
+    public:
+        FakeStatsEventDelegate() = default;
+        ~FakeStatsEventDelegate() override = default;
+
+        struct stats_event* addStatsEventToPullData(pulled_stats_event_list*) override {
+            return mEvent;
+        }
+        void registerStatsPullAtomCallback(int32_t atom_tag, stats_pull_atom_callback_t callback,
+                                           pull_atom_metadata*, void* cookie) override {
+            mAtomTag = atom_tag;
+            mCallback = callback;
+            mCookie = cookie;
+        }
+
+        status_pull_atom_return_t makePullAtomCallback(int32_t atom_tag, void* cookie) {
+            return (*mCallback)(atom_tag, nullptr, cookie);
+        }
+
+        MOCK_METHOD1(unregisterStatsPullAtomCallback, void(int32_t));
+        MOCK_METHOD2(statsEventSetAtomId, void(struct stats_event*, uint32_t));
+        MOCK_METHOD2(statsEventWriteInt64, void(struct stats_event*, int64_t));
+        MOCK_METHOD1(statsEventBuild, void(struct stats_event*));
+
+        struct stats_event* mEvent = stats_event_obtain();
+        int32_t mAtomTag = 0;
+        stats_pull_atom_callback_t mCallback = nullptr;
+        void* mCookie = nullptr;
+    };
+
+    FakeStatsEventDelegate* mDelegate = new FakeStatsEventDelegate;
+    std::unique_ptr<TimeStats> mTimeStats =
+            std::make_unique<impl::TimeStats>(std::unique_ptr<FakeStatsEventDelegate>(mDelegate));
 };
 
 std::string TimeStatsTest::inputCommand(InputCommand cmd, bool useProto) {
@@ -213,14 +248,22 @@
     return distr(mRandomEngine);
 }
 
-TEST_F(TimeStatsTest, enabledByDefault) {
+TEST_F(TimeStatsTest, disabledByDefault) {
+    ASSERT_FALSE(mTimeStats->isEnabled());
+}
+
+TEST_F(TimeStatsTest, enabledAfterBoot) {
+    mTimeStats->onBootFinished();
     ASSERT_TRUE(mTimeStats->isEnabled());
 }
 
 TEST_F(TimeStatsTest, canEnableAndDisableTimeStats) {
     EXPECT_TRUE(inputCommand(InputCommand::ENABLE, FMT_STRING).empty());
     ASSERT_TRUE(mTimeStats->isEnabled());
+    EXPECT_EQ(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO, mDelegate->mAtomTag);
 
+    EXPECT_CALL(*mDelegate,
+                unregisterStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO));
     EXPECT_TRUE(inputCommand(InputCommand::DISABLE, FMT_STRING).empty());
     ASSERT_FALSE(mTimeStats->isEnabled());
 }
@@ -631,6 +674,56 @@
     ASSERT_EQ(0, globalProto.stats_size());
 }
 
+TEST_F(TimeStatsTest, globalStatsCallback) {
+    constexpr size_t TOTAL_FRAMES = 5;
+    constexpr size_t MISSED_FRAMES = 4;
+    constexpr size_t CLIENT_COMPOSITION_FRAMES = 3;
+
+    mTimeStats->onBootFinished();
+    EXPECT_TRUE(inputCommand(InputCommand::ENABLE, FMT_STRING).empty());
+
+    for (size_t i = 0; i < TOTAL_FRAMES; i++) {
+        mTimeStats->incrementTotalFrames();
+    }
+    for (size_t i = 0; i < MISSED_FRAMES; i++) {
+        mTimeStats->incrementMissedFrames();
+    }
+    for (size_t i = 0; i < CLIENT_COMPOSITION_FRAMES; i++) {
+        mTimeStats->incrementClientCompositionFrames();
+    }
+
+    mTimeStats->setPowerMode(HWC_POWER_MODE_NORMAL);
+    mTimeStats->setPresentFenceGlobal(std::make_shared<FenceTime>(3000000));
+    mTimeStats->setPresentFenceGlobal(std::make_shared<FenceTime>(5000000));
+
+    EXPECT_EQ(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO, mDelegate->mAtomTag);
+    EXPECT_NE(nullptr, mDelegate->mCallback);
+    EXPECT_EQ(mTimeStats.get(), mDelegate->mCookie);
+
+    {
+        InSequence seq;
+        EXPECT_CALL(*mDelegate,
+                    statsEventSetAtomId(mDelegate->mEvent,
+                                        android::util::SURFACEFLINGER_STATS_GLOBAL_INFO));
+        EXPECT_CALL(*mDelegate, statsEventWriteInt64(mDelegate->mEvent, TOTAL_FRAMES));
+        EXPECT_CALL(*mDelegate, statsEventWriteInt64(mDelegate->mEvent, MISSED_FRAMES));
+        EXPECT_CALL(*mDelegate, statsEventWriteInt64(mDelegate->mEvent, CLIENT_COMPOSITION_FRAMES));
+        EXPECT_CALL(*mDelegate, statsEventWriteInt64(mDelegate->mEvent, _));
+        EXPECT_CALL(*mDelegate, statsEventWriteInt64(mDelegate->mEvent, 2));
+        EXPECT_CALL(*mDelegate, statsEventBuild(mDelegate->mEvent));
+    }
+    EXPECT_EQ(STATS_PULL_SUCCESS,
+              mDelegate->makePullAtomCallback(mDelegate->mAtomTag, mDelegate->mCookie));
+
+    SFTimeStatsGlobalProto globalProto;
+    ASSERT_TRUE(globalProto.ParseFromString(inputCommand(InputCommand::DUMP_ALL, FMT_PROTO)));
+
+    EXPECT_EQ(0, globalProto.total_frames());
+    EXPECT_EQ(0, globalProto.missed_frames());
+    EXPECT_EQ(0, globalProto.client_composition_frames());
+    EXPECT_EQ(0, globalProto.present_to_present_size());
+}
+
 TEST_F(TimeStatsTest, canSurviveMonkey) {
     if (g_noSlowTests) {
         GTEST_SKIP();
diff --git a/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h b/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h
index ec74a42..9ada5ef 100644
--- a/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h
+++ b/services/surfaceflinger/tests/unittests/mock/MockTimeStats.h
@@ -28,6 +28,7 @@
     TimeStats();
     ~TimeStats() override;
 
+    MOCK_METHOD0(onBootFinished, void());
     MOCK_METHOD3(parseArgs, void(bool, const Vector<String16>&, std::string&));
     MOCK_METHOD0(isEnabled, bool());
     MOCK_METHOD0(miniDump, std::string());