diff --git a/services/surfaceflinger/Scheduler/MessageQueue.cpp b/services/surfaceflinger/Scheduler/MessageQueue.cpp
index 9b04497..dec8f59 100644
--- a/services/surfaceflinger/Scheduler/MessageQueue.cpp
+++ b/services/surfaceflinger/Scheduler/MessageQueue.cpp
@@ -17,12 +17,12 @@
 #define ATRACE_TAG ATRACE_TAG_GRAPHICS
 
 #include <binder/IPCThreadState.h>
-
+#include <gui/DisplayEventReceiver.h>
 #include <utils/Log.h>
 #include <utils/Timers.h>
 #include <utils/threads.h>
 
-#include <gui/DisplayEventReceiver.h>
+#include <scheduler/interface/ICompositor.h>
 
 #include "EventThread.h"
 #include "FrameTimeline.h"
diff --git a/services/surfaceflinger/Scheduler/MessageQueue.h b/services/surfaceflinger/Scheduler/MessageQueue.h
index ad0ea72..0d59337 100644
--- a/services/surfaceflinger/Scheduler/MessageQueue.h
+++ b/services/surfaceflinger/Scheduler/MessageQueue.h
@@ -37,15 +37,7 @@
 
 namespace android {
 
-struct ICompositor {
-    virtual void configure() = 0;
-    virtual bool commit(TimePoint frameTime, VsyncId, TimePoint expectedVsyncTime) = 0;
-    virtual void composite(TimePoint frameTime, VsyncId) = 0;
-    virtual void sample() = 0;
-
-protected:
-    ~ICompositor() = default;
-};
+struct ICompositor;
 
 template <typename F>
 class Task : public MessageHandler {
diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index 1fc1519..1e97f35 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -34,6 +34,8 @@
 #include <utils/Trace.h>
 
 #include <FrameTimeline/FrameTimeline.h>
+#include <scheduler/interface/ICompositor.h>
+
 #include <algorithm>
 #include <cinttypes>
 #include <cstdint>
diff --git a/services/surfaceflinger/Scheduler/include/scheduler/interface/CompositionCoverage.h b/services/surfaceflinger/Scheduler/include/scheduler/interface/CompositionCoverage.h
new file mode 100644
index 0000000..3d0f1a9
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/include/scheduler/interface/CompositionCoverage.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2023 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 <cstdint>
+
+#include <ftl/flags.h>
+
+namespace android {
+
+// Whether composition was covered by HWC and/or GPU.
+enum class CompositionCoverage : std::uint8_t {
+    Hwc = 1 << 0,
+
+    // Mutually exclusive: The composition either used the GPU, or reused a buffer that had been
+    // composited on the GPU.
+    Gpu = 1 << 1,
+    GpuReuse = 1 << 2,
+};
+
+using CompositionCoverageFlags = ftl::Flags<CompositionCoverage>;
+
+} // namespace android
diff --git a/services/surfaceflinger/Scheduler/include/scheduler/interface/ICompositor.h b/services/surfaceflinger/Scheduler/include/scheduler/interface/ICompositor.h
new file mode 100644
index 0000000..cc41925
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/include/scheduler/interface/ICompositor.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2023 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 <scheduler/Time.h>
+#include <scheduler/VsyncId.h>
+
+namespace android {
+
+struct ICompositor {
+    // Configures physical displays, processing hotplug and/or mode setting via the Composer HAL.
+    virtual void configure() = 0;
+
+    // Commits transactions for layers and displays. Returns whether any state has been invalidated,
+    // i.e. whether a frame should be composited for each display.
+    virtual bool commit(TimePoint frameTime, VsyncId, TimePoint expectedVsyncTime) = 0;
+
+    // Composites a frame for each display. CompositionEngine performs GPU and/or HAL composition
+    // via RenderEngine and the Composer HAL, respectively.
+    virtual void composite(TimePoint frameTime, VsyncId) = 0;
+
+    // Samples the composited frame via RegionSamplingThread.
+    virtual void sample() = 0;
+
+protected:
+    ~ICompositor() = default;
+};
+
+} // namespace android