diff --git a/libs/input/input_flags.aconfig b/libs/input/input_flags.aconfig
index 0c850fe..174464d 100644
--- a/libs/input/input_flags.aconfig
+++ b/libs/input/input_flags.aconfig
@@ -26,6 +26,13 @@
   namespace: "input"
   description: "Set to true to enable timer support for the touchpad Gestures library"
   bug: "297192727"
+ }
+
+ flag {
+  name: "enable_input_event_tracing"
+  namespace: "input"
+  description: "Set to true to enable input event tracing, including always-on tracing on non-user builds"
+  bug: "210460522"
 }
 
 flag {
diff --git a/services/inputflinger/Android.bp b/services/inputflinger/Android.bp
index a7955cf..2d6838b 100644
--- a/services/inputflinger/Android.bp
+++ b/services/inputflinger/Android.bp
@@ -110,6 +110,7 @@
     ],
     static_libs: [
         "libattestation",
+        "libperfetto_client_experimental",
         "libpalmrejection",
         "libui-types",
     ],
diff --git a/services/inputflinger/dispatcher/Android.bp b/services/inputflinger/dispatcher/Android.bp
index c7bacee..582eeeb 100644
--- a/services/inputflinger/dispatcher/Android.bp
+++ b/services/inputflinger/dispatcher/Android.bp
@@ -49,6 +49,7 @@
         "Monitor.cpp",
         "TouchedWindow.cpp",
         "TouchState.cpp",
+        "trace/*.cpp",
     ],
 }
 
@@ -72,6 +73,7 @@
     static_libs: [
         "libattestation",
         "libgui_window_info_static",
+        "libperfetto_client_experimental",
     ],
     target: {
         android: {
diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp
index c349a58..efc9b3a 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.cpp
+++ b/services/inputflinger/dispatcher/InputDispatcher.cpp
@@ -51,6 +51,8 @@
 #include "Connection.h"
 #include "DebugConfig.h"
 #include "InputDispatcher.h"
+#include "trace/InputTracer.h"
+#include "trace/InputTracingPerfettoBackend.h"
 
 #define INDENT "  "
 #define INDENT2 "    "
@@ -75,6 +77,14 @@
 
 namespace {
 
+// Input tracing is only available on debuggable builds (userdebug and eng) when the feature
+// flag is enabled. When the flag is changed, tracing will only be available after reboot.
+bool isInputTracingEnabled() {
+    static const std::string buildType = base::GetProperty("ro.build.type", "user");
+    static const bool isUserdebugOrEng = buildType == "userdebug" || buildType == "eng";
+    return input_flags::enable_input_event_tracing() && isUserdebugOrEng;
+}
+
 template <class Entry>
 void ensureEventTraced(const Entry& entry) {
     if (!entry.traceTracker) {
@@ -804,7 +814,9 @@
 // --- InputDispatcher ---
 
 InputDispatcher::InputDispatcher(InputDispatcherPolicyInterface& policy)
-      : InputDispatcher(policy, nullptr) {}
+      : InputDispatcher(policy,
+                        isInputTracingEnabled() ? std::make_unique<trace::impl::PerfettoBackend>()
+                                                : nullptr) {}
 
 InputDispatcher::InputDispatcher(InputDispatcherPolicyInterface& policy,
                                  std::unique_ptr<trace::InputTracingBackendInterface> traceBackend)
@@ -833,7 +845,7 @@
     mKeyRepeatState.lastKeyEntry = nullptr;
 
     if (traceBackend) {
-        // TODO: Create input tracer instance.
+        mTracer = std::make_unique<trace::impl::InputTracer>(std::move(traceBackend));
     }
 
     mLastUserActivityTimes.fill(0);
diff --git a/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.cpp b/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.cpp
new file mode 100644
index 0000000..a15ad80
--- /dev/null
+++ b/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.cpp
@@ -0,0 +1,74 @@
+/*
+ * Copyright 2024 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.
+ */
+
+#include "AndroidInputEventProtoConverter.h"
+
+#include <android-base/logging.h>
+#include <perfetto/trace/android/android_input_event.pbzero.h>
+
+namespace android::inputdispatcher::trace {
+
+void AndroidInputEventProtoConverter::toProtoMotionEvent(const TracedMotionEvent& event,
+                                                         proto::AndroidMotionEvent& outProto) {
+    outProto.set_event_id(event.id);
+    outProto.set_event_time_nanos(event.eventTime);
+    outProto.set_down_time_nanos(event.downTime);
+    outProto.set_source(event.source);
+    outProto.set_action(event.action);
+    outProto.set_device_id(event.deviceId);
+    outProto.set_display_id(event.displayId);
+    outProto.set_classification(static_cast<int32_t>(event.classification));
+    outProto.set_cursor_position_x(event.xCursorPosition);
+    outProto.set_cursor_position_y(event.yCursorPosition);
+    outProto.set_flags(event.flags);
+    outProto.set_policy_flags(event.policyFlags);
+
+    for (uint32_t i = 0; i < event.pointerProperties.size(); i++) {
+        auto* pointer = outProto.add_pointer();
+
+        const auto& props = event.pointerProperties[i];
+        pointer->set_pointer_id(props.id);
+        pointer->set_tool_type(static_cast<int32_t>(props.toolType));
+
+        const auto& coords = event.pointerCoords[i];
+        auto bits = BitSet64(coords.bits);
+        for (int32_t axisIndex = 0; !bits.isEmpty(); axisIndex++) {
+            const auto axis = bits.clearFirstMarkedBit();
+            auto axisEntry = pointer->add_axis_value();
+            axisEntry->set_axis(axis);
+            axisEntry->set_value(coords.values[axisIndex]);
+        }
+    }
+}
+
+void AndroidInputEventProtoConverter::toProtoKeyEvent(const TracedKeyEvent& event,
+                                                      proto::AndroidKeyEvent& outProto) {
+    outProto.set_event_id(event.id);
+    outProto.set_event_time_nanos(event.eventTime);
+    outProto.set_down_time_nanos(event.downTime);
+    outProto.set_source(event.source);
+    outProto.set_action(event.action);
+    outProto.set_device_id(event.deviceId);
+    outProto.set_display_id(event.displayId);
+    outProto.set_key_code(event.keyCode);
+    outProto.set_scan_code(event.scanCode);
+    outProto.set_meta_state(event.metaState);
+    outProto.set_repeat_count(event.repeatCount);
+    outProto.set_flags(event.flags);
+    outProto.set_policy_flags(event.policyFlags);
+}
+
+} // namespace android::inputdispatcher::trace
diff --git a/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.h b/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.h
new file mode 100644
index 0000000..fd23238
--- /dev/null
+++ b/services/inputflinger/dispatcher/trace/AndroidInputEventProtoConverter.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2024 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 <perfetto/trace/android/android_input_event.pbzero.h>
+
+#include "InputTracingBackendInterface.h"
+
+namespace proto = perfetto::protos::pbzero;
+
+namespace android::inputdispatcher::trace {
+
+/**
+ * Write traced events into Perfetto protos.
+ */
+class AndroidInputEventProtoConverter {
+public:
+    static void toProtoMotionEvent(const TracedMotionEvent& event,
+                                   proto::AndroidMotionEvent& outProto);
+    static void toProtoKeyEvent(const TracedKeyEvent& event, proto::AndroidKeyEvent& outProto);
+};
+
+} // namespace android::inputdispatcher::trace
diff --git a/services/inputflinger/dispatcher/trace/InputTracer.cpp b/services/inputflinger/dispatcher/trace/InputTracer.cpp
new file mode 100644
index 0000000..60f574d
--- /dev/null
+++ b/services/inputflinger/dispatcher/trace/InputTracer.cpp
@@ -0,0 +1,178 @@
+/*
+ * Copyright 2024 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.
+ */
+
+#define LOG_TAG "InputTracer"
+
+#include "InputTracer.h"
+
+#include <android-base/logging.h>
+
+namespace android::inputdispatcher::trace::impl {
+
+namespace {
+
+TracedEvent createTracedEvent(const MotionEntry& e) {
+    return TracedMotionEvent{e.id,
+                             e.eventTime,
+                             e.policyFlags,
+                             e.deviceId,
+                             e.source,
+                             e.displayId,
+                             e.action,
+                             e.actionButton,
+                             e.flags,
+                             e.metaState,
+                             e.buttonState,
+                             e.classification,
+                             e.edgeFlags,
+                             e.xPrecision,
+                             e.yPrecision,
+                             e.xCursorPosition,
+                             e.yCursorPosition,
+                             e.downTime,
+                             e.pointerProperties,
+                             e.pointerCoords};
+}
+
+TracedEvent createTracedEvent(const KeyEntry& e) {
+    return TracedKeyEvent{e.id,        e.eventTime, e.policyFlags, e.deviceId, e.source,
+                          e.displayId, e.action,    e.keyCode,     e.scanCode, e.metaState,
+                          e.downTime,  e.flags,     e.repeatCount};
+}
+
+} // namespace
+
+// --- InputTracer ---
+
+InputTracer::InputTracer(std::unique_ptr<InputTracingBackendInterface> backend)
+      : mTracerThread(&InputTracer::threadLoop, this), mBackend(std::move(backend)) {}
+
+InputTracer::~InputTracer() {
+    {
+        std::scoped_lock lock(mLock);
+        mThreadExit = true;
+    }
+    mThreadWakeCondition.notify_all();
+    mTracerThread.join();
+}
+
+std::unique_ptr<EventTrackerInterface> InputTracer::traceInboundEvent(const EventEntry& entry) {
+    std::scoped_lock lock(mLock);
+    TracedEvent traced;
+
+    if (entry.type == EventEntry::Type::MOTION) {
+        const auto& motion = static_cast<const MotionEntry&>(entry);
+        traced = createTracedEvent(motion);
+    } else if (entry.type == EventEntry::Type::KEY) {
+        const auto& key = static_cast<const KeyEntry&>(entry);
+        traced = createTracedEvent(key);
+    } else {
+        LOG(FATAL) << "Cannot trace EventEntry of type: " << ftl::enum_string(entry.type);
+    }
+
+    return std::make_unique<EventTrackerImpl>(*this, std::move(traced));
+}
+
+void InputTracer::dispatchToTargetHint(const EventTrackerInterface& cookie,
+                                       const InputTarget& target) {
+    std::scoped_lock lock(mLock);
+    auto& cookieState = getState(cookie);
+    if (!cookieState) {
+        LOG(FATAL) << "dispatchToTargetHint() should not be called after eventProcessingComplete()";
+    }
+    // TODO(b/210460522): Determine if the event is sensitive based on the target.
+}
+
+void InputTracer::eventProcessingComplete(const EventTrackerInterface& cookie) {
+    {
+        std::scoped_lock lock(mLock);
+        auto& cookieState = getState(cookie);
+        if (!cookieState) {
+            LOG(FATAL) << "Traced event was already logged. "
+                          "eventProcessingComplete() was likely called more than once.";
+        }
+        mTraceQueue.emplace_back(std::move(*cookieState));
+        cookieState.reset();
+    } // release lock
+
+    mThreadWakeCondition.notify_all();
+}
+
+void InputTracer::traceEventDispatch(const DispatchEntry& dispatchEntry,
+                                     const EventTrackerInterface* cookie) {}
+
+std::optional<InputTracer::EventState>& InputTracer::getState(const EventTrackerInterface& cookie) {
+    return static_cast<const EventTrackerImpl&>(cookie).mLockedState;
+}
+
+void InputTracer::threadLoop() {
+    while (true) {
+        std::vector<const EventState> eventsToTrace;
+        {
+            std::unique_lock lock(mLock);
+            base::ScopedLockAssertion assumeLocked(mLock);
+            if (mThreadExit) {
+                return;
+            }
+            if (mTraceQueue.empty()) {
+                // Wait indefinitely until the thread is awoken.
+                mThreadWakeCondition.wait(lock);
+            }
+
+            mTraceQueue.swap(eventsToTrace);
+        } // release lock
+
+        // Trace the events into the backend without holding the lock to reduce the amount of
+        // work performed in the critical section.
+        writeEventsToBackend(eventsToTrace);
+        eventsToTrace.clear();
+    }
+}
+
+void InputTracer::writeEventsToBackend(const std::vector<const EventState>& events) {
+    for (const auto& event : events) {
+        if (auto* motion = std::get_if<TracedMotionEvent>(&event.event); motion != nullptr) {
+            mBackend->traceMotionEvent(*motion);
+        } else {
+            mBackend->traceKeyEvent(std::get<TracedKeyEvent>(event.event));
+        }
+    }
+}
+
+// --- InputTracer::EventTrackerImpl ---
+
+InputTracer::EventTrackerImpl::EventTrackerImpl(InputTracer& tracer, TracedEvent&& event)
+      : mTracer(tracer), mLockedState(event) {}
+
+InputTracer::EventTrackerImpl::~EventTrackerImpl() {
+    {
+        std::scoped_lock lock(mTracer.mLock);
+        if (!mLockedState) {
+            // This event has already been written to the trace as expected.
+            return;
+        }
+        // We're still holding on to the state, which means it hasn't yet been written to the trace.
+        // Write it to the trace now.
+        // TODO(b/210460522): Determine why/where the event is being destroyed before
+        //   eventProcessingComplete() is called.
+        mTracer.mTraceQueue.emplace_back(std::move(*mLockedState));
+        mLockedState.reset();
+    } // release lock
+
+    mTracer.mThreadWakeCondition.notify_all();
+}
+
+} // namespace android::inputdispatcher::trace::impl
diff --git a/services/inputflinger/dispatcher/trace/InputTracer.h b/services/inputflinger/dispatcher/trace/InputTracer.h
new file mode 100644
index 0000000..97f3a2b
--- /dev/null
+++ b/services/inputflinger/dispatcher/trace/InputTracer.h
@@ -0,0 +1,96 @@
+/*
+ * Copyright 2024 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 "InputTracerInterface.h"
+
+#include <android-base/thread_annotations.h>
+#include <gui/WindowInfo.h>
+
+#include <memory>
+#include <mutex>
+#include <thread>
+#include <unordered_set>
+#include <vector>
+
+#include "../Entry.h"
+#include "InputTracingBackendInterface.h"
+
+namespace android::inputdispatcher::trace::impl {
+
+/**
+ * The tracer implementation for InputDispatcher.
+ *
+ * InputTracer is thread-safe, so it can be called from any thread. Upon construction, InputTracer
+ * will start its own thread that it uses for write events into the tracing backend. That is the
+ * one and only thread that will interact with the tracing backend, since the Perfetto backend
+ * uses thread-local storage.
+ *
+ * See the documentation in InputTracerInterface for the API surface.
+ */
+class InputTracer : public InputTracerInterface {
+public:
+    explicit InputTracer(std::unique_ptr<InputTracingBackendInterface>);
+    ~InputTracer() override;
+    InputTracer(const InputTracer&) = delete;
+    InputTracer& operator=(const InputTracer&) = delete;
+
+    std::unique_ptr<EventTrackerInterface> traceInboundEvent(const EventEntry&) override;
+    void dispatchToTargetHint(const EventTrackerInterface&, const InputTarget&) override;
+    void eventProcessingComplete(const EventTrackerInterface&) override;
+    void traceEventDispatch(const DispatchEntry&, const EventTrackerInterface*) override;
+
+private:
+    std::mutex mLock;
+    std::thread mTracerThread;
+    bool mThreadExit GUARDED_BY(mLock){false};
+    std::condition_variable mThreadWakeCondition;
+    std::unique_ptr<InputTracingBackendInterface> mBackend;
+
+    // The state of a tracked event.
+    struct EventState {
+        const TracedEvent event;
+        // TODO(b/210460522): Add additional args for tracking event sensitivity and
+        //  dispatch target UIDs.
+    };
+    std::vector<const EventState> mTraceQueue GUARDED_BY(mLock);
+
+    // Provides thread-safe access to the state from an event tracker cookie.
+    std::optional<EventState>& getState(const EventTrackerInterface&) REQUIRES(mLock);
+
+    // Implementation of the event tracker cookie.
+    class EventTrackerImpl : public EventTrackerInterface {
+    public:
+        explicit EventTrackerImpl(InputTracer&, TracedEvent&& entry);
+        virtual ~EventTrackerImpl() override;
+
+    private:
+        InputTracer& mTracer;
+        // This event tracker cookie will only hold the state as long as it has not been written
+        // to the trace. The state is released when the event is written to the trace.
+        mutable std::optional<EventState> mLockedState;
+
+        // Only allow InputTracer access to the locked state through getTrackerState() to ensure
+        // that the InputTracer lock is held when this is accessed.
+        friend std::optional<EventState>& InputTracer::getState(const EventTrackerInterface&);
+    };
+
+    void threadLoop();
+    void writeEventsToBackend(const std::vector<const EventState>& events);
+};
+
+} // namespace android::inputdispatcher::trace::impl
diff --git a/services/inputflinger/dispatcher/trace/InputTracingPerfettoBackend.cpp b/services/inputflinger/dispatcher/trace/InputTracingPerfettoBackend.cpp
new file mode 100644
index 0000000..db88726
--- /dev/null
+++ b/services/inputflinger/dispatcher/trace/InputTracingPerfettoBackend.cpp
@@ -0,0 +1,88 @@
+/*
+ * Copyright 2024 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.
+ */
+
+#define LOG_TAG "InputTracer"
+
+#include "InputTracingPerfettoBackend.h"
+
+#include "AndroidInputEventProtoConverter.h"
+
+#include <android-base/logging.h>
+#include <perfetto/trace/android/android_input_event.pbzero.h>
+
+namespace android::inputdispatcher::trace::impl {
+
+namespace {
+
+constexpr auto INPUT_EVENT_TRACE_DATA_SOURCE_NAME = "android.input.inputevent";
+
+} // namespace
+
+// --- PerfettoBackend::InputEventDataSource ---
+
+void PerfettoBackend::InputEventDataSource::OnStart(const perfetto::DataSourceBase::StartArgs&) {
+    LOG(INFO) << "Starting perfetto trace for: " << INPUT_EVENT_TRACE_DATA_SOURCE_NAME;
+}
+
+void PerfettoBackend::InputEventDataSource::OnStop(const perfetto::DataSourceBase::StopArgs&) {
+    LOG(INFO) << "Stopping perfetto trace for: " << INPUT_EVENT_TRACE_DATA_SOURCE_NAME;
+    InputEventDataSource::Trace([&](InputEventDataSource::TraceContext ctx) { ctx.Flush(); });
+}
+
+// --- PerfettoBackend ---
+
+std::once_flag PerfettoBackend::sDataSourceRegistrationFlag{};
+
+PerfettoBackend::PerfettoBackend() {
+    // Use a once-flag to ensure that the data source is only registered once per boot, since
+    // we never unregister the InputEventDataSource.
+    std::call_once(sDataSourceRegistrationFlag, []() {
+        perfetto::TracingInitArgs args;
+        args.backends = perfetto::kSystemBackend;
+        perfetto::Tracing::Initialize(args);
+
+        // Register our custom data source for input event tracing.
+        perfetto::DataSourceDescriptor dsd;
+        dsd.set_name(INPUT_EVENT_TRACE_DATA_SOURCE_NAME);
+        InputEventDataSource::Register(dsd);
+        LOG(INFO) << "InputTracer initialized for data source: "
+                  << INPUT_EVENT_TRACE_DATA_SOURCE_NAME;
+    });
+}
+
+void PerfettoBackend::traceMotionEvent(const TracedMotionEvent& event) const {
+    InputEventDataSource::Trace([&](InputEventDataSource::TraceContext ctx) {
+        auto tracePacket = ctx.NewTracePacket();
+        auto* inputEvent = tracePacket->set_android_input_event();
+        auto* dispatchMotion = inputEvent->set_dispatcher_motion_event();
+        AndroidInputEventProtoConverter::toProtoMotionEvent(event, *dispatchMotion);
+    });
+}
+
+void PerfettoBackend::traceKeyEvent(const TracedKeyEvent& event) const {
+    InputEventDataSource::Trace([&](InputEventDataSource::TraceContext ctx) {
+        auto tracePacket = ctx.NewTracePacket();
+        auto* inputEvent = tracePacket->set_android_input_event();
+        auto* dispatchKey = inputEvent->set_dispatcher_key_event();
+        AndroidInputEventProtoConverter::toProtoKeyEvent(event, *dispatchKey);
+    });
+}
+
+void PerfettoBackend::traceWindowDispatch(const WindowDispatchArgs&) const {
+    // TODO(b/210460522): Implement.
+}
+
+} // namespace android::inputdispatcher::trace::impl
diff --git a/services/inputflinger/dispatcher/trace/InputTracingPerfettoBackend.h b/services/inputflinger/dispatcher/trace/InputTracingPerfettoBackend.h
new file mode 100644
index 0000000..2777cfe
--- /dev/null
+++ b/services/inputflinger/dispatcher/trace/InputTracingPerfettoBackend.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2024 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 "InputTracingBackendInterface.h"
+
+#include <perfetto/tracing.h>
+#include <mutex>
+
+namespace android::inputdispatcher::trace::impl {
+
+/**
+ * The tracing backend that writes events into ongoing Perfetto traces.
+ *
+ * Example shell command to take an input trace from Perfetto:
+ *
+ *   adb shell  perfetto \
+ *    -c - --txt \
+ *    -o /data/misc/perfetto-traces/trace.input-trace \
+ *    <<END
+ *    buffers: {
+ *      size_kb: 5000
+ *      fill_policy: RING_BUFFER
+ *    }
+ *    data_sources: {
+ *      config {
+ *          name: "android.input.inputevent"
+ *      }
+ *    }
+ *    END
+ */
+class PerfettoBackend : public InputTracingBackendInterface {
+public:
+    PerfettoBackend();
+    ~PerfettoBackend() override = default;
+
+    void traceKeyEvent(const TracedKeyEvent&) const override;
+    void traceMotionEvent(const TracedMotionEvent&) const override;
+    void traceWindowDispatch(const WindowDispatchArgs&) const override;
+
+    class InputEventDataSource : public perfetto::DataSource<InputEventDataSource> {
+    public:
+        void OnSetup(const SetupArgs&) override {}
+        void OnStart(const StartArgs&) override;
+        void OnStop(const StopArgs&) override;
+    };
+
+private:
+    static std::once_flag sDataSourceRegistrationFlag;
+};
+
+} // namespace android::inputdispatcher::trace::impl
diff --git a/services/inputflinger/tests/InputDispatcher_test.cpp b/services/inputflinger/tests/InputDispatcher_test.cpp
index f1f4a61..9c8c409 100644
--- a/services/inputflinger/tests/InputDispatcher_test.cpp
+++ b/services/inputflinger/tests/InputDispatcher_test.cpp
@@ -665,7 +665,7 @@
 
     void SetUp() override {
         mFakePolicy = std::make_unique<FakeInputDispatcherPolicy>();
-        mDispatcher = std::make_unique<InputDispatcher>(*mFakePolicy);
+        mDispatcher = std::make_unique<InputDispatcher>(*mFakePolicy, nullptr);
 
         mDispatcher->setInputDispatchMode(/*enabled=*/true, /*frozen=*/false);
         // Start InputDispatcher thread
@@ -7090,12 +7090,9 @@
     sp<FakeWindowHandle> mWindow;
 
     virtual void SetUp() override {
-        mFakePolicy = std::make_unique<FakeInputDispatcherPolicy>();
-        mDispatcher = std::make_unique<InputDispatcher>(*mFakePolicy);
-        mDispatcher->setInputDispatchMode(/*enabled=*/true, /*frozen=*/false);
-        mDispatcher->setKeyRepeatConfiguration(KEY_REPEAT_TIMEOUT, KEY_REPEAT_DELAY);
-        ASSERT_EQ(OK, mDispatcher->start());
+        InputDispatcherTest::SetUp();
 
+        mDispatcher->setKeyRepeatConfiguration(KEY_REPEAT_TIMEOUT, KEY_REPEAT_DELAY);
         setUpWindow();
     }