Merge "Add SDK support for CPU/GPU headroom APIs" into main

13 files changed, 848 insertions, 24 deletions

diff --git a/core/api/current.txt b/core/api/current.txt
index df681d43e2d1..89850a5d864a 100644
--- a/core/api/current.txt
+++ b/core/api/current.txt
@@ -33344,6 +33344,14 @@ package android.os {
     method public final android.os.CountDownTimer start();
   }
 
+  @FlaggedApi("android.os.cpu_gpu_headrooms") public final class CpuHeadroomParams {
+    ctor public CpuHeadroomParams();
+    method public int getCalculationType();
+    method public void setCalculationType(int);
+    field public static final int CPU_HEADROOM_CALCULATION_TYPE_AVERAGE = 1; // 0x1
+    field public static final int CPU_HEADROOM_CALCULATION_TYPE_MIN = 0; // 0x0
+  }
+
   public final class CpuUsageInfo implements android.os.Parcelable {
     method public int describeContents();
     method public long getActive();
@@ -33591,6 +33599,14 @@ package android.os {
     method public void onProgress(long);
   }
 
+  @FlaggedApi("android.os.cpu_gpu_headrooms") public final class GpuHeadroomParams {
+    ctor public GpuHeadroomParams();
+    method public int getCalculationType();
+    method public void setCalculationType(int);
+    field public static final int GPU_HEADROOM_CALCULATION_TYPE_AVERAGE = 1; // 0x1
+    field public static final int GPU_HEADROOM_CALCULATION_TYPE_MIN = 0; // 0x0
+  }
+
   public class Handler {
     ctor @Deprecated public Handler();
     ctor @Deprecated public Handler(@Nullable android.os.Handler.Callback);
@@ -34841,6 +34857,10 @@ package android.os.health {
   }
 
   public class SystemHealthManager {
+    method @FlaggedApi("android.os.cpu_gpu_headrooms") @FloatRange(from=0.0f, to=100.0f) public float getCpuHeadroom(@Nullable android.os.CpuHeadroomParams);
+    method @FlaggedApi("android.os.cpu_gpu_headrooms") public long getCpuHeadroomMinIntervalMillis();
+    method @FlaggedApi("android.os.cpu_gpu_headrooms") @FloatRange(from=0.0f, to=100.0f) public float getGpuHeadroom(@Nullable android.os.GpuHeadroomParams);
+    method @FlaggedApi("android.os.cpu_gpu_headrooms") public long getGpuHeadroomMinIntervalMillis();
     method @FlaggedApi("com.android.server.power.optimization.power_monitor_api") public void getPowerMonitorReadings(@NonNull java.util.List<android.os.PowerMonitor>, @Nullable java.util.concurrent.Executor, @NonNull android.os.OutcomeReceiver<android.os.PowerMonitorReadings,java.lang.RuntimeException>);
     method @FlaggedApi("com.android.server.power.optimization.power_monitor_api") public void getSupportedPowerMonitors(@Nullable java.util.concurrent.Executor, @NonNull java.util.function.Consumer<java.util.List<android.os.PowerMonitor>>);
     method public android.os.health.HealthStats takeMyUidSnapshot();
diff --git a/core/java/Android.bp b/core/java/Android.bp
index cf5ebbaa37b4..bc38294279a8 100644
--- a/core/java/Android.bp
+++ b/core/java/Android.bp
@@ -232,6 +232,8 @@ aidl_interface {
         "android.hardware.power-aidl",
     ],
     srcs: [
+        "android/os/CpuHeadroomParamsInternal.aidl",
+        "android/os/GpuHeadroomParamsInternal.aidl",
         "android/os/IHintManager.aidl",
         "android/os/IHintSession.aidl",
     ],
diff --git a/core/java/android/app/SystemServiceRegistry.java b/core/java/android/app/SystemServiceRegistry.java
index e451116081fa..ee0c38c60ff1 100644
--- a/core/java/android/app/SystemServiceRegistry.java
+++ b/core/java/android/app/SystemServiceRegistry.java
@@ -190,6 +190,7 @@ import android.os.IBatteryPropertiesRegistrar;
 import android.os.IBinder;
 import android.os.IDumpstate;
 import android.os.IHardwarePropertiesManager;
+import android.os.IHintManager;
 import android.os.IPowerManager;
 import android.os.IPowerStatsService;
 import android.os.IRecoverySystem;
@@ -1195,8 +1196,10 @@ public final class SystemServiceRegistry {
             public SystemHealthManager createService(ContextImpl ctx) throws ServiceNotFoundException {
                 IBinder batteryStats = ServiceManager.getServiceOrThrow(BatteryStats.SERVICE_NAME);
                 IBinder powerStats = ServiceManager.getService(Context.POWER_STATS_SERVICE);
+                IBinder perfHint = ServiceManager.getService(Context.PERFORMANCE_HINT_SERVICE);
                 return new SystemHealthManager(IBatteryStats.Stub.asInterface(batteryStats),
-                        IPowerStatsService.Stub.asInterface(powerStats));
+                        IPowerStatsService.Stub.asInterface(powerStats),
+                        IHintManager.Stub.asInterface(perfHint));
             }});
 
         registerService(Context.CONTEXTHUB_SERVICE, ContextHubManager.class,
diff --git a/core/java/android/os/CpuHeadroomParams.java b/core/java/android/os/CpuHeadroomParams.java
new file mode 100644
index 000000000000..f0d4f7d8737f
--- /dev/null
+++ b/core/java/android/os/CpuHeadroomParams.java
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 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.
+ */
+
+package android.os;
+
+import android.annotation.FlaggedApi;
+import android.annotation.IntDef;
+import android.os.health.SystemHealthManager;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Headroom request params used by {@link SystemHealthManager#getCpuHeadroom(CpuHeadroomParams)}.
+ */
+@FlaggedApi(Flags.FLAG_CPU_GPU_HEADROOMS)
+public final class CpuHeadroomParams {
+    final CpuHeadroomParamsInternal mInternal;
+
+    public CpuHeadroomParams() {
+        mInternal = new CpuHeadroomParamsInternal();
+    }
+
+    /** @hide */
+    @IntDef(flag = false, prefix = {"CPU_HEADROOM_CALCULATION_TYPE_"}, value = {
+            CPU_HEADROOM_CALCULATION_TYPE_MIN, // 0
+            CPU_HEADROOM_CALCULATION_TYPE_AVERAGE, // 1
+    })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface CpuHeadroomCalculationType {
+    }
+
+    /**
+     * Calculates the headroom based on minimum value over a device-defined window.
+     */
+    public static final int CPU_HEADROOM_CALCULATION_TYPE_MIN = 0;
+
+    /**
+     * Calculates the headroom based on average value over a device-defined window.
+     */
+    public static final int CPU_HEADROOM_CALCULATION_TYPE_AVERAGE = 1;
+
+    /**
+     * Sets the headroom calculation type.
+     * <p>
+     *
+     * @throws IllegalArgumentException if the type is invalid.
+     */
+    public void setCalculationType(@CpuHeadroomCalculationType int calculationType) {
+        switch (calculationType) {
+            case CPU_HEADROOM_CALCULATION_TYPE_MIN:
+            case CPU_HEADROOM_CALCULATION_TYPE_AVERAGE:
+                mInternal.calculationType = (byte) calculationType;
+                return;
+        }
+        throw new IllegalArgumentException("Invalid calculation type: " + calculationType);
+    }
+
+    /**
+     * Gets the headroom calculation type.
+     * Default to {@link #CPU_HEADROOM_CALCULATION_TYPE_MIN} if not set.
+     */
+    public @CpuHeadroomCalculationType int getCalculationType() {
+        @CpuHeadroomCalculationType int validatedType = switch ((int) mInternal.calculationType) {
+            case CPU_HEADROOM_CALCULATION_TYPE_MIN, CPU_HEADROOM_CALCULATION_TYPE_AVERAGE ->
+                    mInternal.calculationType;
+            default -> CPU_HEADROOM_CALCULATION_TYPE_MIN;
+        };
+        return validatedType;
+    }
+
+    /**
+     * @hide
+     */
+    public CpuHeadroomParamsInternal getInternal() {
+        return mInternal;
+    }
+}
diff --git a/core/java/android/os/CpuHeadroomParamsInternal.aidl b/core/java/android/os/CpuHeadroomParamsInternal.aidl
new file mode 100644
index 000000000000..6cc4699a809e
--- /dev/null
+++ b/core/java/android/os/CpuHeadroomParamsInternal.aidl
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 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.
+ */
+
+package android.os;
+
+import android.hardware.power.CpuHeadroomParams;
+
+/**
+ * Changes should be synced with match function of HintManagerService#CpuHeadroomCacheItem.
+ * {@hide}
+ */
+@JavaDerive(equals = true, toString = true)
+parcelable CpuHeadroomParamsInternal {
+    boolean usesDeviceHeadroom = false;
+    CpuHeadroomParams.CalculationType calculationType = CpuHeadroomParams.CalculationType.MIN;
+    CpuHeadroomParams.SelectionType selectionType = CpuHeadroomParams.SelectionType.ALL;
+}
+
diff --git a/core/java/android/os/GpuHeadroomParams.java b/core/java/android/os/GpuHeadroomParams.java
new file mode 100644
index 000000000000..efb2a28ad2b5
--- /dev/null
+++ b/core/java/android/os/GpuHeadroomParams.java
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 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.
+ */
+
+package android.os;
+
+import android.annotation.FlaggedApi;
+import android.annotation.IntDef;
+import android.os.health.SystemHealthManager;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Headroom request params used by {@link SystemHealthManager#getGpuHeadroom(GpuHeadroomParams)}.
+ */
+@FlaggedApi(Flags.FLAG_CPU_GPU_HEADROOMS)
+public final class GpuHeadroomParams {
+    final GpuHeadroomParamsInternal mInternal;
+
+    public GpuHeadroomParams() {
+        mInternal = new GpuHeadroomParamsInternal();
+    }
+
+    /** @hide */
+    @IntDef(flag = false, prefix = {"GPU_HEADROOM_CALCULATION_TYPE_"}, value = {
+            GPU_HEADROOM_CALCULATION_TYPE_MIN, // 0
+            GPU_HEADROOM_CALCULATION_TYPE_AVERAGE, // 1
+    })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface GpuHeadroomCalculationType {
+    }
+
+    /**
+     * Calculates the headroom based on minimum value over a device-defined window.
+     */
+    public static final int GPU_HEADROOM_CALCULATION_TYPE_MIN = 0;
+
+    /**
+     * Calculates the headroom based on average value over a device-defined window.
+     */
+    public static final int GPU_HEADROOM_CALCULATION_TYPE_AVERAGE = 1;
+
+    /**
+     * Sets the headroom calculation type.
+     * <p>
+     *
+     * @throws IllegalArgumentException if the type is invalid.
+     */
+    public void setCalculationType(@GpuHeadroomCalculationType int calculationType) {
+        switch (calculationType) {
+            case GPU_HEADROOM_CALCULATION_TYPE_MIN:
+            case GPU_HEADROOM_CALCULATION_TYPE_AVERAGE:
+                mInternal.calculationType = (byte) calculationType;
+                return;
+        }
+        throw new IllegalArgumentException("Invalid calculation type: " + calculationType);
+    }
+
+    /**
+     * Gets the headroom calculation type.
+     * Default to {@link #GPU_HEADROOM_CALCULATION_TYPE_MIN} if not set.
+     */
+    public @GpuHeadroomCalculationType int getCalculationType() {
+        @GpuHeadroomCalculationType int validatedType = switch ((int) mInternal.calculationType) {
+            case GPU_HEADROOM_CALCULATION_TYPE_MIN, GPU_HEADROOM_CALCULATION_TYPE_AVERAGE ->
+                    mInternal.calculationType;
+            default -> GPU_HEADROOM_CALCULATION_TYPE_MIN;
+        };
+        return validatedType;
+    }
+
+    /**
+     * @hide
+     */
+    public GpuHeadroomParamsInternal getInternal() {
+        return mInternal;
+    }
+}
diff --git a/core/java/android/os/GpuHeadroomParamsInternal.aidl b/core/java/android/os/GpuHeadroomParamsInternal.aidl
new file mode 100644
index 000000000000..20309e7673f2
--- /dev/null
+++ b/core/java/android/os/GpuHeadroomParamsInternal.aidl
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 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.
+ */
+
+package android.os;
+
+import android.hardware.power.GpuHeadroomParams;
+
+/**
+ * Changes should be synced with match function of HintManagerService#GpuHeadroomCacheItem.
+ * {@hide}
+ */
+@JavaDerive(equals = true, toString = true)
+parcelable GpuHeadroomParamsInternal {
+    GpuHeadroomParams.CalculationType calculationType = GpuHeadroomParams.CalculationType.MIN;
+}
diff --git a/core/java/android/os/IHintManager.aidl b/core/java/android/os/IHintManager.aidl
index 73cdd5682f31..33120556339f 100644
--- a/core/java/android/os/IHintManager.aidl
+++ b/core/java/android/os/IHintManager.aidl
@@ -17,6 +17,8 @@
 
 package android.os;
 
+import android.os.CpuHeadroomParamsInternal;
+import android.os.GpuHeadroomParamsInternal;
 import android.os.IHintSession;
 import android.hardware.power.ChannelConfig;
 import android.hardware.power.SessionConfig;
@@ -50,4 +52,8 @@ interface IHintManager {
      */
     @nullable ChannelConfig getSessionChannel(in IBinder token);
     oneway void closeSessionChannel();
+    float[] getCpuHeadroom(in CpuHeadroomParamsInternal params);
+    long getCpuHeadroomMinIntervalMillis();
+    float getGpuHeadroom(in GpuHeadroomParamsInternal params);
+    long getGpuHeadroomMinIntervalMillis();
 }
diff --git a/core/java/android/os/flags.aconfig b/core/java/android/os/flags.aconfig
index d9db28e0b3c3..095799cce646 100644
--- a/core/java/android/os/flags.aconfig
+++ b/core/java/android/os/flags.aconfig
@@ -148,6 +148,13 @@ flag {
 }
 
 flag {
+    name: "cpu_gpu_headrooms"
+    namespace: "game"
+    description: "Feature flag for adding CPU/GPU headroom API"
+    bug: "346604998"
+}
+
+flag {
     name: "disallow_cellular_null_ciphers_restriction"
     namespace: "cellular_security"
     description: "Guards a new UserManager user restriction that admins can use to require cellular encryption on their managed devices."
diff --git a/core/java/android/os/health/SystemHealthManager.java b/core/java/android/os/health/SystemHealthManager.java
index deabfed365a6..4db9bc333e2b 100644
--- a/core/java/android/os/health/SystemHealthManager.java
+++ b/core/java/android/os/health/SystemHealthManager.java
@@ -17,6 +17,7 @@
 package android.os.health;
 
 import android.annotation.FlaggedApi;
+import android.annotation.FloatRange;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.annotation.SystemService;
@@ -25,6 +26,11 @@ import android.content.Context;
 import android.os.BatteryStats;
 import android.os.Build;
 import android.os.Bundle;
+import android.os.CpuHeadroomParams;
+import android.os.CpuHeadroomParamsInternal;
+import android.os.GpuHeadroomParams;
+import android.os.GpuHeadroomParamsInternal;
+import android.os.IHintManager;
 import android.os.IPowerStatsService;
 import android.os.OutcomeReceiver;
 import android.os.PowerMonitor;
@@ -68,6 +74,8 @@ public class SystemHealthManager {
     private final IBatteryStats mBatteryStats;
     @Nullable
     private final IPowerStatsService mPowerStats;
+    @Nullable
+    private final IHintManager mHintManager;
     private List<PowerMonitor> mPowerMonitorsInfo;
     private final Object mPowerMonitorsLock = new Object();
     private static final long TAKE_UID_SNAPSHOT_TIMEOUT_MILLIS = 10_000;
@@ -88,14 +96,111 @@ public class SystemHealthManager {
     public SystemHealthManager() {
         this(IBatteryStats.Stub.asInterface(ServiceManager.getService(BatteryStats.SERVICE_NAME)),
                 IPowerStatsService.Stub.asInterface(
-                        ServiceManager.getService(Context.POWER_STATS_SERVICE)));
+                        ServiceManager.getService(Context.POWER_STATS_SERVICE)),
+                IHintManager.Stub.asInterface(
+                        ServiceManager.getService(Context.PERFORMANCE_HINT_SERVICE)));
     }
 
     /** {@hide} */
     public SystemHealthManager(@NonNull IBatteryStats batteryStats,
-            @Nullable IPowerStatsService powerStats) {
+            @Nullable IPowerStatsService powerStats, @Nullable IHintManager hintManager) {
         mBatteryStats = batteryStats;
         mPowerStats = powerStats;
+        mHintManager = hintManager;
+    }
+
+    /**
+     * Provides an estimate of global available CPU headroom of the calling thread.
+     * <p>
+     *
+     * @param  params params to customize the CPU headroom calculation, null to use default params.
+     * @return a single value a {@code Float.NaN} if it's temporarily unavailable.
+     *         A valid value is ranged from [0, 100], where 0 indicates no more CPU resources can be
+     *         granted.
+     * @throws UnsupportedOperationException if the API is unsupported or the request params can't
+     *         be served.
+     */
+    @FlaggedApi(android.os.Flags.FLAG_CPU_GPU_HEADROOMS)
+    public @FloatRange(from = 0f, to = 100f) float getCpuHeadroom(
+            @Nullable CpuHeadroomParams params) {
+        if (mHintManager == null) {
+            throw new UnsupportedOperationException();
+        }
+        try {
+            return mHintManager.getCpuHeadroom(
+                    params != null ? params.getInternal() : new CpuHeadroomParamsInternal())[0];
+        } catch (RemoteException re) {
+            throw re.rethrowFromSystemServer();
+        }
+    }
+
+
+
+    /**
+     * Provides an estimate of global available GPU headroom of the device.
+     * <p>
+     *
+     * @param  params params to customize the GPU headroom calculation, null to use default params.
+     * @return a single value headroom or a {@code Float.NaN} if it's temporarily unavailable.
+     *         A valid value is ranged from [0, 100], where 0 indicates no more GPU resources can be
+     *         granted.
+     * @throws UnsupportedOperationException if the API is unsupported or the request params can't
+     *         be served.
+     */
+    @FlaggedApi(android.os.Flags.FLAG_CPU_GPU_HEADROOMS)
+    public @FloatRange(from = 0f, to = 100f) float getGpuHeadroom(
+            @Nullable GpuHeadroomParams params) {
+        if (mHintManager == null) {
+            throw new UnsupportedOperationException();
+        }
+        try {
+            return mHintManager.getGpuHeadroom(
+                    params != null ? params.getInternal() : new GpuHeadroomParamsInternal());
+        } catch (RemoteException re) {
+            throw re.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Minimum polling interval for calling {@link #getCpuHeadroom(CpuHeadroomParams)} in
+     * milliseconds.
+     * <p>
+     * The {@link #getCpuHeadroom(CpuHeadroomParams)} API may return cached result if called more
+     * frequent than the interval.
+     *
+     * @throws UnsupportedOperationException if the API is unsupported.
+     */
+    @FlaggedApi(android.os.Flags.FLAG_CPU_GPU_HEADROOMS)
+    public long getCpuHeadroomMinIntervalMillis() {
+        if (mHintManager == null) {
+            throw new UnsupportedOperationException();
+        }
+        try {
+            return mHintManager.getCpuHeadroomMinIntervalMillis();
+        } catch (RemoteException re) {
+            throw re.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Minimum polling interval for calling {@link #getGpuHeadroom(GpuHeadroomParams)} in
+     * milliseconds.
+     * <p>
+     * The {@link #getGpuHeadroom(GpuHeadroomParams)} API may return cached result if called more
+     * frequent than the interval.
+     *
+     * @throws UnsupportedOperationException if the API is unsupported.
+     */
+    @FlaggedApi(android.os.Flags.FLAG_CPU_GPU_HEADROOMS)
+    public long getGpuHeadroomMinIntervalMillis() {
+        if (mHintManager == null) {
+            throw new UnsupportedOperationException();
+        }
+        try {
+            return mHintManager.getGpuHeadroomMinIntervalMillis();
+        } catch (RemoteException re) {
+            throw re.rethrowFromSystemServer();
+        }
     }
 
     /**
@@ -261,7 +366,7 @@ public class SystemHealthManager {
                         mPowerMonitorsInfo = result;
                     }
                     if (executor != null) {
-                        executor.execute(()-> onResult.accept(result));
+                        executor.execute(() -> onResult.accept(result));
                     } else {
                         onResult.accept(result);
                     }
diff --git a/native/android/tests/performance_hint/PerformanceHintNativeTest.cpp b/native/android/tests/performance_hint/PerformanceHintNativeTest.cpp
index 9de3a6f525e6..641e8d9a9b48 100644
--- a/native/android/tests/performance_hint/PerformanceHintNativeTest.cpp
+++ b/native/android/tests/performance_hint/PerformanceHintNativeTest.cpp
@@ -66,6 +66,18 @@ public:
                  std::optional<hal::ChannelConfig>* _aidl_return),
                 (override));
     MOCK_METHOD(ScopedAStatus, closeSessionChannel, (), (override));
+    MOCK_METHOD(ScopedAStatus, getCpuHeadroom,
+                (const ::aidl::android::os::CpuHeadroomParamsInternal& in_params,
+                 std::vector<float>* _aidl_return),
+                (override));
+    MOCK_METHOD(ScopedAStatus, getCpuHeadroomMinIntervalMillis, (int64_t* _aidl_return),
+                (override));
+    MOCK_METHOD(ScopedAStatus, getGpuHeadroom,
+                (const ::aidl::android::os::GpuHeadroomParamsInternal& in_params,
+                 float* _aidl_return),
+                (override));
+    MOCK_METHOD(ScopedAStatus, getGpuHeadroomMinIntervalMillis, (int64_t* _aidl_return),
+                (override));
     MOCK_METHOD(SpAIBinder, asBinder, (), (override));
     MOCK_METHOD(bool, isRemote, (), (override));
 };
diff --git a/services/core/java/com/android/server/power/hint/HintManagerService.java b/services/core/java/com/android/server/power/hint/HintManagerService.java
index 2c0ce252df18..17459df2bc1a 100644
--- a/services/core/java/com/android/server/power/hint/HintManagerService.java
+++ b/services/core/java/com/android/server/power/hint/HintManagerService.java
@@ -33,11 +33,15 @@ import android.content.Context;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
 import android.hardware.power.ChannelConfig;
+import android.hardware.power.CpuHeadroomParams;
+import android.hardware.power.GpuHeadroomParams;
 import android.hardware.power.IPower;
 import android.hardware.power.SessionConfig;
 import android.hardware.power.SessionTag;
 import android.hardware.power.WorkDuration;
 import android.os.Binder;
+import android.os.CpuHeadroomParamsInternal;
+import android.os.GpuHeadroomParamsInternal;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.IHintManager;
@@ -90,6 +94,10 @@ public final class HintManagerService extends SystemService {
 
     private static final int EVENT_CLEAN_UP_UID = 3;
     @VisibleForTesting  static final int CLEAN_UP_UID_DELAY_MILLIS = 1000;
+    private static final int DEFAULT_GPU_HEADROOM_INTERVAL_MILLIS = 1000;
+    private static final int DEFAULT_CPU_HEADROOM_INTERVAL_MILLIS = 1000;
+    private static final int HEADROOM_INTERVAL_UNSUPPORTED = -1;
+    @VisibleForTesting static final int DEFAULT_HEADROOM_PID = -1;
 
 
     @VisibleForTesting final long mHintSessionPreferredRate;
@@ -160,10 +168,76 @@ public final class HintManagerService extends SystemService {
 
     private static final String PROPERTY_SF_ENABLE_CPU_HINT = "debug.sf.enable_adpf_cpu_hint";
     private static final String PROPERTY_HWUI_ENABLE_HINT_MANAGER = "debug.hwui.use_hint_manager";
+    private static final String PROPERTY_USE_HAL_HEADROOMS = "persist.hms.use_hal_headrooms";
 
     private Boolean mFMQUsesIntegratedEventFlag = false;
 
-    @VisibleForTesting final IHintManager.Stub mService = new BinderService();
+    private final Object mCpuHeadroomLock = new Object();
+
+    private static class CpuHeadroomCacheItem {
+        long mExpiredTimeMillis;
+        CpuHeadroomParamsInternal mParams;
+        float[] mHeadroom;
+        long mPid;
+
+        CpuHeadroomCacheItem(long expiredTimeMillis, CpuHeadroomParamsInternal params,
+                float[] headroom, long pid) {
+            mExpiredTimeMillis = expiredTimeMillis;
+            mParams = params;
+            mPid = pid;
+            mHeadroom = headroom;
+        }
+
+        private boolean match(CpuHeadroomParamsInternal params, long pid) {
+            if (mParams == null && params == null) return true;
+            if (mParams != null) {
+                return mParams.equals(params) && pid == mPid;
+            }
+            return false;
+        }
+
+        private boolean isExpired() {
+            return System.currentTimeMillis() > mExpiredTimeMillis;
+        }
+    }
+
+    @GuardedBy("mCpuHeadroomLock")
+    private final List<CpuHeadroomCacheItem> mCpuHeadroomCache;
+    private final long mCpuHeadroomIntervalMillis;
+
+    private final Object mGpuHeadroomLock = new Object();
+
+    private static class GpuHeadroomCacheItem {
+        long mExpiredTimeMillis;
+        GpuHeadroomParamsInternal mParams;
+        float mHeadroom;
+
+        GpuHeadroomCacheItem(long expiredTimeMillis, GpuHeadroomParamsInternal params,
+                float headroom) {
+            mExpiredTimeMillis = expiredTimeMillis;
+            mParams = params;
+            mHeadroom = headroom;
+        }
+
+        private boolean match(GpuHeadroomParamsInternal params) {
+            if (mParams == null && params == null) return true;
+            if (mParams != null) {
+                return mParams.equals(params);
+            }
+            return false;
+        }
+
+        private boolean isExpired() {
+            return System.currentTimeMillis() > mExpiredTimeMillis;
+        }
+    }
+
+    @GuardedBy("mGpuHeadroomLock")
+    private final List<GpuHeadroomCacheItem> mGpuHeadroomCache;
+    private final long mGpuHeadroomIntervalMillis;
+
+    @VisibleForTesting
+    final IHintManager.Stub mService = new BinderService();
 
     public HintManagerService(Context context) {
         this(context, new Injector());
@@ -197,13 +271,72 @@ public final class HintManagerService extends SystemService {
         mPowerHal = injector.createIPower();
         mPowerHalVersion = 0;
         mUsesFmq = false;
+        long cpuHeadroomIntervalMillis = HEADROOM_INTERVAL_UNSUPPORTED;
+        long gpuHeadroomIntervalMillis = HEADROOM_INTERVAL_UNSUPPORTED;
         if (mPowerHal != null) {
             try {
                 mPowerHalVersion = mPowerHal.getInterfaceVersion();
+                if (mPowerHal.getInterfaceVersion() >= 6) {
+                    if (SystemProperties.getBoolean(PROPERTY_USE_HAL_HEADROOMS, true)) {
+                        cpuHeadroomIntervalMillis = checkCpuHeadroomSupport();
+                        gpuHeadroomIntervalMillis = checkGpuHeadroomSupport();
+                    }
+                }
             } catch (RemoteException e) {
                 throw new IllegalStateException("Could not contact PowerHAL!", e);
             }
         }
+        mCpuHeadroomIntervalMillis = cpuHeadroomIntervalMillis;
+        mGpuHeadroomIntervalMillis = gpuHeadroomIntervalMillis;
+        if (mCpuHeadroomIntervalMillis > 0) {
+            mCpuHeadroomCache = new ArrayList<>(4);
+        } else {
+            mCpuHeadroomCache = null;
+        }
+        if (mGpuHeadroomIntervalMillis > 0) {
+            mGpuHeadroomCache = new ArrayList<>(2);
+        } else {
+            mGpuHeadroomCache = null;
+        }
+    }
+
+    private long checkCpuHeadroomSupport() {
+        try {
+            synchronized (mCpuHeadroomLock) {
+                final CpuHeadroomParams defaultParams = new CpuHeadroomParams();
+                defaultParams.pid = Process.myPid();
+                float[] ret = mPowerHal.getCpuHeadroom(defaultParams);
+                if (ret != null && ret.length > 0) {
+                    return Math.max(
+                            DEFAULT_CPU_HEADROOM_INTERVAL_MILLIS,
+                            mPowerHal.getCpuHeadroomMinIntervalMillis());
+                }
+            }
+
+        } catch (UnsupportedOperationException e) {
+            Slog.w(TAG, "getCpuHeadroom HAL API is not supported", e);
+        } catch (RemoteException e) {
+            Slog.e(TAG, "getCpuHeadroom HAL API fails, disabling the API", e);
+        }
+        return HEADROOM_INTERVAL_UNSUPPORTED;
+    }
+
+    private long checkGpuHeadroomSupport() {
+        try {
+            synchronized (mGpuHeadroomLock) {
+                float ret = mPowerHal.getGpuHeadroom(new GpuHeadroomParams());
+                if (!Float.isNaN(ret)) {
+                    return Math.max(
+                            DEFAULT_GPU_HEADROOM_INTERVAL_MILLIS,
+                            mPowerHal.getGpuHeadroomMinIntervalMillis());
+                }
+            }
+        } catch (UnsupportedOperationException e) {
+            Slog.w(TAG, "getGpuHeadroom HAL API is not supported", e);
+        } catch (RemoteException e) {
+            Slog.e(TAG, "getGpuHeadroom HAL API fails, disabling the API", e);
+        }
+        return HEADROOM_INTERVAL_UNSUPPORTED;
     }
 
     private ServiceThread createCleanUpThread() {
@@ -738,7 +871,7 @@ public final class HintManagerService extends SystemService {
                 mLinked = false;
             }
             if (mConfig != null) {
-                try  {
+                try {
                     mPowerHal.closeSessionChannel(mTgid, mUid);
                 } catch (RemoteException e) {
                     throw new IllegalStateException("Failed to close session channel!", e);
@@ -982,13 +1115,13 @@ public final class HintManagerService extends SystemService {
     }
 
     // returns the first invalid tid or null if not found
-    private Integer checkTidValid(int uid, int tgid, int [] tids, IntArray nonIsolated) {
+    private Integer checkTidValid(int uid, int tgid, int[] tids, IntArray nonIsolated) {
         // Make sure all tids belongs to the same UID (including isolated UID),
         // tids can belong to different application processes.
         List<Integer> isolatedPids = null;
         for (int i = 0; i < tids.length; i++) {
             int tid = tids[i];
-            final String[] procStatusKeys = new String[] {
+            final String[] procStatusKeys = new String[]{
                     "Uid:",
                     "Tgid:"
             };
@@ -1058,7 +1191,7 @@ public final class HintManagerService extends SystemService {
                     Slogf.w(TAG, errMsg);
                     throw new SecurityException(errMsg);
                 }
-                if (resetOnForkEnabled()){
+                if (resetOnForkEnabled()) {
                     try {
                         for (int tid : tids) {
                             int policy = Process.getThreadScheduler(tid);
@@ -1214,6 +1347,124 @@ public final class HintManagerService extends SystemService {
         }
 
         @Override
+        public float[] getCpuHeadroom(@Nullable CpuHeadroomParamsInternal params) {
+            if (mCpuHeadroomIntervalMillis <= 0) {
+                throw new UnsupportedOperationException();
+            }
+            CpuHeadroomParams halParams = new CpuHeadroomParams();
+            halParams.pid = Binder.getCallingPid();
+            if (params != null) {
+                halParams.calculationType = params.calculationType;
+                halParams.selectionType = params.selectionType;
+                if (params.usesDeviceHeadroom) {
+                    halParams.pid = DEFAULT_HEADROOM_PID;
+                }
+            }
+            synchronized (mCpuHeadroomLock) {
+                while (!mCpuHeadroomCache.isEmpty()) {
+                    if (mCpuHeadroomCache.getFirst().isExpired()) {
+                        mCpuHeadroomCache.removeFirst();
+                    } else {
+                        break;
+                    }
+                }
+                for (int i = 0; i < mCpuHeadroomCache.size(); ++i) {
+                    final CpuHeadroomCacheItem item = mCpuHeadroomCache.get(i);
+                    if (item.match(params, halParams.pid)) {
+                        item.mExpiredTimeMillis =
+                                System.currentTimeMillis() + mCpuHeadroomIntervalMillis;
+                        mCpuHeadroomCache.remove(i);
+                        mCpuHeadroomCache.add(item);
+                        return item.mHeadroom;
+                    }
+                }
+            }
+            // return from HAL directly
+            try {
+                float[] headroom = mPowerHal.getCpuHeadroom(halParams);
+                if (headroom == null || headroom.length == 0) {
+                    Slog.wtf(TAG,
+                            "CPU headroom from Power HAL is invalid: " + Arrays.toString(headroom));
+                    return new float[]{Float.NaN};
+                }
+                synchronized (mCpuHeadroomLock) {
+                    mCpuHeadroomCache.add(new CpuHeadroomCacheItem(
+                            System.currentTimeMillis() + mCpuHeadroomIntervalMillis,
+                            params, headroom, halParams.pid
+                    ));
+                }
+                return headroom;
+
+            } catch (RemoteException e) {
+                return new float[]{Float.NaN};
+            }
+        }
+
+        @Override
+        public float getGpuHeadroom(@Nullable GpuHeadroomParamsInternal params) {
+            if (mGpuHeadroomIntervalMillis <= 0) {
+                throw new UnsupportedOperationException();
+            }
+            GpuHeadroomParams halParams = new GpuHeadroomParams();
+            if (params != null) {
+                halParams.calculationType = params.calculationType;
+            }
+            synchronized (mGpuHeadroomLock) {
+                while (!mGpuHeadroomCache.isEmpty()) {
+                    if (mGpuHeadroomCache.getFirst().isExpired()) {
+                        mGpuHeadroomCache.removeFirst();
+                    } else {
+                        break;
+                    }
+                }
+                for (int i = 0; i < mGpuHeadroomCache.size(); ++i) {
+                    final GpuHeadroomCacheItem item = mGpuHeadroomCache.get(i);
+                    if (item.match(params)) {
+                        item.mExpiredTimeMillis =
+                                System.currentTimeMillis() + mGpuHeadroomIntervalMillis;
+                        mGpuHeadroomCache.remove(i);
+                        mGpuHeadroomCache.add(item);
+                        return item.mHeadroom;
+                    }
+                }
+            }
+            // return from HAL directly
+            try {
+                float headroom = mPowerHal.getGpuHeadroom(halParams);
+                if (Float.isNaN(headroom)) {
+                    Slog.wtf(TAG,
+                            "GPU headroom from Power HAL is NaN");
+                    return Float.NaN;
+                }
+                synchronized (mGpuHeadroomLock) {
+                    mGpuHeadroomCache.add(new GpuHeadroomCacheItem(
+                            System.currentTimeMillis() + mGpuHeadroomIntervalMillis,
+                            params, headroom
+                    ));
+                }
+                return headroom;
+            } catch (RemoteException e) {
+                return Float.NaN;
+            }
+        }
+
+        @Override
+        public long getCpuHeadroomMinIntervalMillis() throws RemoteException {
+            if (mCpuHeadroomIntervalMillis <= 0) {
+                throw new UnsupportedOperationException();
+            }
+            return mCpuHeadroomIntervalMillis;
+        }
+
+        @Override
+        public long getGpuHeadroomMinIntervalMillis() throws RemoteException {
+            if (mGpuHeadroomIntervalMillis <= 0) {
+                throw new UnsupportedOperationException();
+            }
+            return mGpuHeadroomIntervalMillis;
+        }
+
+        @Override
         public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
             if (!DumpUtils.checkDumpPermission(getContext(), TAG, pw)) {
                 return;
@@ -1235,6 +1486,25 @@ public final class HintManagerService extends SystemService {
                     }
                 }
             }
+            pw.println("CPU Headroom Interval: " + mCpuHeadroomIntervalMillis);
+            pw.println("GPU Headroom Interval: " + mGpuHeadroomIntervalMillis);
+            try {
+                CpuHeadroomParamsInternal params = new CpuHeadroomParamsInternal();
+                params.selectionType = CpuHeadroomParams.SelectionType.ALL;
+                params.usesDeviceHeadroom = true;
+                pw.println("CPU headroom: " + Arrays.toString(getCpuHeadroom(params)));
+                params = new CpuHeadroomParamsInternal();
+                params.selectionType = CpuHeadroomParams.SelectionType.PER_CORE;
+                params.usesDeviceHeadroom = true;
+                pw.println("CPU headroom per core: " + Arrays.toString(getCpuHeadroom(params)));
+            } catch (Exception e) {
+                pw.println("CPU headroom: N/A");
+            }
+            try {
+                pw.println("GPU headroom: " + getGpuHeadroom(null));
+            } catch (Exception e) {
+                pw.println("GPU headroom: N/A");
+            }
         }
 
         private void logPerformanceHintSessionAtom(int uid, long sessionId,
@@ -1467,7 +1737,7 @@ public final class HintManagerService extends SystemService {
                             Slogf.w(TAG, errMsg);
                             throw new SecurityException(errMsg);
                         }
-                        if (resetOnForkEnabled()){
+                        if (resetOnForkEnabled()) {
                             try {
                                 for (int tid : tids) {
                                     int policy = Process.getThreadScheduler(tid);
diff --git a/services/tests/performancehinttests/src/com/android/server/power/hint/HintManagerServiceTest.java b/services/tests/performancehinttests/src/com/android/server/power/hint/HintManagerServiceTest.java
index 58489f398775..0881b4cf9bcf 100644
--- a/services/tests/performancehinttests/src/com/android/server/power/hint/HintManagerServiceTest.java
+++ b/services/tests/performancehinttests/src/com/android/server/power/hint/HintManagerServiceTest.java
@@ -18,6 +18,7 @@ package com.android.server.power.hint;
 
 
 import static com.android.server.power.hint.HintManagerService.CLEAN_UP_UID_DELAY_MILLIS;
+import static com.android.server.power.hint.HintManagerService.DEFAULT_HEADROOM_PID;
 
 import static com.google.common.truth.Truth.assertThat;
 
@@ -51,11 +52,15 @@ import android.content.pm.PackageManager;
 import android.hardware.common.fmq.MQDescriptor;
 import android.hardware.power.ChannelConfig;
 import android.hardware.power.ChannelMessage;
+import android.hardware.power.CpuHeadroomParams;
+import android.hardware.power.GpuHeadroomParams;
 import android.hardware.power.IPower;
 import android.hardware.power.SessionConfig;
 import android.hardware.power.SessionTag;
 import android.hardware.power.WorkDuration;
 import android.os.Binder;
+import android.os.CpuHeadroomParamsInternal;
+import android.os.GpuHeadroomParamsInternal;
 import android.os.IBinder;
 import android.os.IHintSession;
 import android.os.PerformanceHintManager;
@@ -128,11 +133,11 @@ public class HintManagerServiceTest {
     private static final long[] TIMESTAMPS_ZERO = new long[] {};
     private static final long[] TIMESTAMPS_TWO = new long[] {1L, 2L};
     private static final WorkDuration[] WORK_DURATIONS_FIVE = new WorkDuration[] {
-        makeWorkDuration(1L, 11L, 1L, 8L, 4L),
-        makeWorkDuration(2L, 13L, 2L, 8L, 6L),
-        makeWorkDuration(3L, 333333333L, 3L, 8L, 333333333L),
-        makeWorkDuration(2L, 13L, 2L, 0L, 6L),
-        makeWorkDuration(2L, 13L, 2L, 8L, 0L),
+            makeWorkDuration(1L, 11L, 1L, 8L, 4L),
+            makeWorkDuration(2L, 13L, 2L, 8L, 6L),
+            makeWorkDuration(3L, 333333333L, 3L, 8L, 333333333L),
+            makeWorkDuration(2L, 13L, 2L, 0L, 6L),
+            makeWorkDuration(2L, 13L, 2L, 8L, 0L),
     };
     private static final String TEST_APP_NAME = "com.android.test.app";
 
@@ -187,17 +192,17 @@ public class HintManagerServiceTest {
         when(mNativeWrapperMock.halCreateHintSessionWithConfig(eq(TGID), eq(UID),
                 eq(SESSION_TIDS_A), eq(DEFAULT_TARGET_DURATION), anyInt(),
                 any(SessionConfig.class))).thenAnswer(fakeCreateWithConfig(SESSION_PTRS[0],
-                    SESSION_IDS[0]));
+                SESSION_IDS[0]));
         when(mNativeWrapperMock.halCreateHintSessionWithConfig(eq(TGID), eq(UID),
                 eq(SESSION_TIDS_B), eq(DOUBLED_TARGET_DURATION), anyInt(),
                 any(SessionConfig.class))).thenAnswer(fakeCreateWithConfig(SESSION_PTRS[1],
-                    SESSION_IDS[1]));
+                SESSION_IDS[1]));
         when(mNativeWrapperMock.halCreateHintSessionWithConfig(eq(TGID), eq(UID),
                 eq(SESSION_TIDS_C), eq(0L), anyInt(),
                 any(SessionConfig.class))).thenAnswer(fakeCreateWithConfig(SESSION_PTRS[2],
-                    SESSION_IDS[2]));
+                SESSION_IDS[2]));
 
-        when(mIPowerMock.getInterfaceVersion()).thenReturn(5);
+        when(mIPowerMock.getInterfaceVersion()).thenReturn(6);
         when(mIPowerMock.getSessionChannel(anyInt(), anyInt())).thenReturn(mConfig);
         LocalServices.removeServiceForTest(ActivityManagerInternal.class);
         LocalServices.addService(ActivityManagerInternal.class, mAmInternalMock);
@@ -217,8 +222,8 @@ public class HintManagerServiceTest {
         when(mNativeWrapperMock.halCreateHintSession(eq(TGID), eq(UID), eq(SESSION_TIDS_C),
                 eq(0L))).thenReturn(SESSION_PTRS[2]);
         when(mNativeWrapperMock.halCreateHintSessionWithConfig(anyInt(), anyInt(),
-            any(int[].class), anyLong(), anyInt(),
-            any(SessionConfig.class))).thenThrow(new UnsupportedOperationException());
+                any(int[].class), anyLong(), anyInt(),
+                any(SessionConfig.class))).thenThrow(new UnsupportedOperationException());
     }
 
     static class NativeWrapperFake extends NativeWrapper {
@@ -337,7 +342,7 @@ public class HintManagerServiceTest {
                 SESSION_TIDS_C, 0L, SessionTag.OTHER, new SessionConfig());
         assertNotNull(c);
         verify(mNativeWrapperMock, times(3)).halCreateHintSession(anyInt(), anyInt(),
-                                                                  any(int[].class), anyLong());
+                any(int[].class), anyLong());
     }
 
     @Test
@@ -487,7 +492,7 @@ public class HintManagerServiceTest {
 
         AppHintSession a = (AppHintSession) service.getBinderServiceInstance()
                 .createHintSessionWithConfig(token, SESSION_TIDS_A, DEFAULT_TARGET_DURATION,
-                    SessionTag.OTHER, new SessionConfig());
+                        SessionTag.OTHER, new SessionConfig());
 
         a.sendHint(PerformanceHintManager.Session.CPU_LOAD_RESET);
         verify(mNativeWrapperMock, times(1)).halSendHint(anyLong(),
@@ -514,7 +519,7 @@ public class HintManagerServiceTest {
 
         AppHintSession a = (AppHintSession) service.getBinderServiceInstance()
                 .createHintSessionWithConfig(token, SESSION_TIDS_A, DEFAULT_TARGET_DURATION,
-                    SessionTag.OTHER, new SessionConfig());
+                        SessionTag.OTHER, new SessionConfig());
 
         service.mUidObserver.onUidStateChanged(
                 a.mUid, ActivityManager.PROCESS_STATE_IMPORTANT_BACKGROUND, 0, 0);
@@ -1096,4 +1101,157 @@ public class HintManagerServiceTest {
         verify(mIPowerMock, times(1)).getSessionChannel(eq(TGID), eq(UID));
         assertTrue(service.hasChannel(TGID, UID));
     }
+
+    @Test
+    public void testHeadroomPowerHalNotSupported() throws Exception {
+        when(mIPowerMock.getInterfaceVersion()).thenReturn(5);
+        HintManagerService service = createService();
+        assertThrows(UnsupportedOperationException.class, () -> {
+            service.getBinderServiceInstance().getCpuHeadroom(null);
+        });
+        assertThrows(UnsupportedOperationException.class, () -> {
+            service.getBinderServiceInstance().getGpuHeadroom(null);
+        });
+        assertThrows(UnsupportedOperationException.class, () -> {
+            service.getBinderServiceInstance().getCpuHeadroomMinIntervalMillis();
+        });
+        assertThrows(UnsupportedOperationException.class, () -> {
+            service.getBinderServiceInstance().getGpuHeadroomMinIntervalMillis();
+        });
+    }
+
+    @Test
+    public void testCpuHeadroomCache() throws Exception {
+        when(mIPowerMock.getCpuHeadroomMinIntervalMillis()).thenReturn(2000L);
+        CpuHeadroomParamsInternal params1 = new CpuHeadroomParamsInternal();
+        CpuHeadroomParams halParams1 = new CpuHeadroomParams();
+        halParams1.calculationType = CpuHeadroomParams.CalculationType.MIN;
+        halParams1.selectionType = CpuHeadroomParams.SelectionType.ALL;
+        halParams1.pid = Process.myPid();
+
+        CpuHeadroomParamsInternal params2 = new CpuHeadroomParamsInternal();
+        params2.usesDeviceHeadroom = true;
+        params2.calculationType = CpuHeadroomParams.CalculationType.AVERAGE;
+        params2.selectionType = CpuHeadroomParams.SelectionType.PER_CORE;
+        CpuHeadroomParams halParams2 = new CpuHeadroomParams();
+        halParams2.calculationType = CpuHeadroomParams.CalculationType.AVERAGE;
+        halParams2.selectionType = CpuHeadroomParams.SelectionType.PER_CORE;
+        halParams2.pid = DEFAULT_HEADROOM_PID;
+
+        float[] headroom1 = new float[] {0.1f};
+        when(mIPowerMock.getCpuHeadroom(eq(halParams1))).thenReturn(headroom1);
+        float[] headroom2 = new float[] {0.1f, 0.5f};
+        when(mIPowerMock.getCpuHeadroom(eq(halParams2))).thenReturn(headroom2);
+
+        HintManagerService service = createService();
+        clearInvocations(mIPowerMock);
+
+        service.getBinderServiceInstance().getCpuHeadroomMinIntervalMillis();
+        verify(mIPowerMock, times(0)).getCpuHeadroomMinIntervalMillis();
+        service.getBinderServiceInstance().getCpuHeadroom(params1);
+        verify(mIPowerMock, times(1)).getCpuHeadroom(eq(halParams1));
+        service.getBinderServiceInstance().getCpuHeadroom(params2);
+        verify(mIPowerMock, times(1)).getCpuHeadroom(eq(halParams2));
+
+        // verify cache is working
+        clearInvocations(mIPowerMock);
+        assertArrayEquals(headroom1, service.getBinderServiceInstance().getCpuHeadroom(params1),
+                0.01f);
+        assertArrayEquals(headroom2, service.getBinderServiceInstance().getCpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(0)).getCpuHeadroom(any());
+
+        // after 1 more second it should be served with cache still
+        Thread.sleep(1000);
+        clearInvocations(mIPowerMock);
+        assertArrayEquals(headroom1, service.getBinderServiceInstance().getCpuHeadroom(params1),
+                0.01f);
+        assertArrayEquals(headroom2, service.getBinderServiceInstance().getCpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(0)).getCpuHeadroom(any());
+
+        // after 1.5 more second it should be served with cache still as timer reset
+        Thread.sleep(1500);
+        clearInvocations(mIPowerMock);
+        assertArrayEquals(headroom1, service.getBinderServiceInstance().getCpuHeadroom(params1),
+                0.01f);
+        assertArrayEquals(headroom2, service.getBinderServiceInstance().getCpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(0)).getCpuHeadroom(any());
+
+        // after 2+ seconds it should be served from HAL as it exceeds 2000 millis interval
+        Thread.sleep(2100);
+        clearInvocations(mIPowerMock);
+        assertArrayEquals(headroom1, service.getBinderServiceInstance().getCpuHeadroom(params1),
+                0.01f);
+        assertArrayEquals(headroom2, service.getBinderServiceInstance().getCpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(1)).getCpuHeadroom(eq(halParams1));
+        verify(mIPowerMock, times(1)).getCpuHeadroom(eq(halParams2));
+    }
+
+    @Test
+    public void testGpuHeadroomCache() throws Exception {
+        when(mIPowerMock.getGpuHeadroomMinIntervalMillis()).thenReturn(2000L);
+        GpuHeadroomParamsInternal params1 = new GpuHeadroomParamsInternal();
+        GpuHeadroomParams halParams1 = new GpuHeadroomParams();
+        halParams1.calculationType = GpuHeadroomParams.CalculationType.MIN;
+
+        GpuHeadroomParamsInternal params2 = new GpuHeadroomParamsInternal();
+        GpuHeadroomParams halParams2 = new GpuHeadroomParams();
+        params2.calculationType =
+                halParams2.calculationType = GpuHeadroomParams.CalculationType.AVERAGE;
+
+        float headroom1 = 0.1f;
+        when(mIPowerMock.getGpuHeadroom(eq(halParams1))).thenReturn(headroom1);
+        float headroom2 = 0.2f;
+        when(mIPowerMock.getGpuHeadroom(eq(halParams2))).thenReturn(headroom2);
+        HintManagerService service = createService();
+        clearInvocations(mIPowerMock);
+
+        service.getBinderServiceInstance().getGpuHeadroomMinIntervalMillis();
+        verify(mIPowerMock, times(0)).getGpuHeadroomMinIntervalMillis();
+        assertEquals(headroom1, service.getBinderServiceInstance().getGpuHeadroom(params1),
+                0.01f);
+        assertEquals(headroom2, service.getBinderServiceInstance().getGpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(1)).getGpuHeadroom(eq(halParams1));
+        verify(mIPowerMock, times(1)).getGpuHeadroom(eq(halParams2));
+
+        // verify cache is working
+        clearInvocations(mIPowerMock);
+        assertEquals(headroom1, service.getBinderServiceInstance().getGpuHeadroom(params1),
+                0.01f);
+        assertEquals(headroom2, service.getBinderServiceInstance().getGpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(0)).getGpuHeadroom(any());
+
+        // after 1 more second it should be served with cache still
+        Thread.sleep(1000);
+        clearInvocations(mIPowerMock);
+        assertEquals(headroom1, service.getBinderServiceInstance().getGpuHeadroom(params1),
+                0.01f);
+        assertEquals(headroom2, service.getBinderServiceInstance().getGpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(0)).getGpuHeadroom(any());
+
+        // after 1.5 more second it should be served with cache still as timer reset
+        Thread.sleep(1500);
+        clearInvocations(mIPowerMock);
+        assertEquals(headroom1, service.getBinderServiceInstance().getGpuHeadroom(params1),
+                0.01f);
+        assertEquals(headroom2, service.getBinderServiceInstance().getGpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(0)).getGpuHeadroom(any());
+
+        // after 2+ seconds it should be served from HAL as it exceeds 2000 millis interval
+        Thread.sleep(2100);
+        clearInvocations(mIPowerMock);
+        assertEquals(headroom1, service.getBinderServiceInstance().getGpuHeadroom(params1),
+                0.01f);
+        assertEquals(headroom2, service.getBinderServiceInstance().getGpuHeadroom(params2),
+                0.01f);
+        verify(mIPowerMock, times(1)).getGpuHeadroom(eq(halParams1));
+        verify(mIPowerMock, times(1)).getGpuHeadroom(eq(halParams2));
+    }
 }