Use cache for min max volume getter

Using the IpcDataCache to reduce the number of binder calls between
AudioManager and AudioService. Especially for the get min max stream
volume this makes a lot of sense since they do not change that often.

Flag: android.media.audio.cache_get_stream_min_max_volume
Test: atest AudioManagerTest
Bug: 383667500
Change-Id: I040fb20e100099461a6fd31d10726f6ac3b4b02d

7 files changed, 175 insertions, 2 deletions

diff --git a/media/java/android/media/AudioManager.java b/media/java/android/media/AudioManager.java
index 52eae43f7db9..aa3dbda374be 100644
--- a/media/java/android/media/AudioManager.java
+++ b/media/java/android/media/AudioManager.java
@@ -21,6 +21,7 @@ import static android.companion.virtual.VirtualDeviceParams.POLICY_TYPE_AUDIO;
 import static android.content.Context.DEVICE_ID_DEFAULT;
 import static android.media.audio.Flags.autoPublicVolumeApiHardening;
 import static android.media.audio.Flags.automaticBtDeviceType;
+import static android.media.audio.Flags.cacheGetStreamMinMaxVolume;
 import static android.media.audio.Flags.FLAG_DEPRECATE_STREAM_BT_SCO;
 import static android.media.audio.Flags.FLAG_FOCUS_EXCLUSIVE_WITH_RECORDING;
 import static android.media.audio.Flags.FLAG_FOCUS_FREEZE_TEST_API;
@@ -58,7 +59,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
 import android.media.AudioAttributes.AttributeSystemUsage;
-import android.media.AudioDeviceInfo;
 import android.media.CallbackUtil.ListenerInfo;
 import android.media.audiopolicy.AudioPolicy;
 import android.media.audiopolicy.AudioPolicy.AudioPolicyFocusListener;
@@ -75,6 +75,7 @@ import android.os.Binder;
 import android.os.Build;
 import android.os.Handler;
 import android.os.IBinder;
+import android.os.IpcDataCache;
 import android.os.Looper;
 import android.os.Message;
 import android.os.RemoteException;
@@ -1231,6 +1232,84 @@ public class AudioManager {
     }
 
     /**
+     * API string for caching the min volume for each stream
+     * @hide
+     **/
+    public static final String VOLUME_MIN_CACHING_API = "getStreamMinVolume";
+    /**
+     * API string for caching the max volume for each stream
+     * @hide
+     **/
+    public static final String VOLUME_MAX_CACHING_API = "getStreamMaxVolume";
+    private static final int VOLUME_MIN_MAX_CACHING_SIZE = 16;
+
+    private final IpcDataCache.QueryHandler<VolumeCacheQuery, Integer> mVolQuery =
+            new IpcDataCache.QueryHandler<>() {
+                @Override
+                public Integer apply(VolumeCacheQuery query) {
+                    final IAudioService service = getService();
+                    try {
+                        return switch (query.queryCommand) {
+                            case QUERY_VOL_MIN -> service.getStreamMinVolume(query.stream);
+                            case QUERY_VOL_MAX -> service.getStreamMaxVolume(query.stream);
+                            default -> {
+                                Log.w(TAG, "Not a valid volume cache query: " + query);
+                                yield null;
+                            }
+                        };
+                    } catch (RemoteException e) {
+                        throw e.rethrowFromSystemServer();
+                    }
+                }
+
+            };
+
+    private final IpcDataCache<VolumeCacheQuery, Integer> mVolMinCache =
+            new IpcDataCache<>(VOLUME_MIN_MAX_CACHING_SIZE, IpcDataCache.MODULE_SYSTEM,
+                    VOLUME_MIN_CACHING_API, VOLUME_MIN_CACHING_API, mVolQuery);
+
+    private final IpcDataCache<VolumeCacheQuery, Integer> mVolMaxCache =
+            new IpcDataCache<>(VOLUME_MIN_MAX_CACHING_SIZE, IpcDataCache.MODULE_SYSTEM,
+                    VOLUME_MAX_CACHING_API, VOLUME_MAX_CACHING_API, mVolQuery);
+
+    /**
+     * Used to invalidate the cache for the given API
+     * @hide
+     **/
+    public static void clearVolumeCache(String api) {
+        if (cacheGetStreamMinMaxVolume()) {
+            IpcDataCache.invalidateCache(IpcDataCache.MODULE_SYSTEM, api);
+        }
+    }
+
+    private static final int QUERY_VOL_MIN = 1;
+    private static final int QUERY_VOL_MAX = 2;
+    /** @hide */
+    @IntDef(prefix = "QUERY_VOL", value = {
+            QUERY_VOL_MIN,
+            QUERY_VOL_MAX}
+    )
+    @Retention(RetentionPolicy.SOURCE)
+    private @interface QueryVolCommand {}
+
+    private record VolumeCacheQuery(int stream, @QueryVolCommand int queryCommand) {
+        private String queryVolCommandToString() {
+            return switch (queryCommand) {
+                case QUERY_VOL_MIN -> "getStreamMinVolume";
+                case QUERY_VOL_MAX -> "getStreamMaxVolume";
+                default -> "invalid command";
+            };
+        }
+
+        @NonNull
+        @Override
+        public String toString() {
+            return TextUtils.formatSimple("VolumeCacheQuery(stream=%d, queryCommand=%s)", stream,
+                    queryVolCommandToString());
+        }
+    }
+
+    /**
      * Returns the maximum volume index for a particular stream.
      *
      * @param streamType The stream type whose maximum volume index is returned.
@@ -1238,6 +1317,9 @@ public class AudioManager {
      * @see #getStreamVolume(int)
      */
     public int getStreamMaxVolume(int streamType) {
+        if (cacheGetStreamMinMaxVolume()) {
+            return mVolMaxCache.query(new VolumeCacheQuery(streamType, QUERY_VOL_MAX));
+        }
         final IAudioService service = getService();
         try {
             return service.getStreamMaxVolume(streamType);
@@ -1271,6 +1353,9 @@ public class AudioManager {
      */
     @TestApi
     public int getStreamMinVolumeInt(int streamType) {
+        if (cacheGetStreamMinMaxVolume()) {
+            return mVolMinCache.query(new VolumeCacheQuery(streamType, QUERY_VOL_MIN));
+        }
         final IAudioService service = getService();
         try {
             return service.getStreamMinVolume(streamType);
diff --git a/media/tests/AudioPolicyTest/src/com/android/audiopolicytest/AudioManagerTest.java b/media/tests/AudioPolicyTest/src/com/android/audiopolicytest/AudioManagerTest.java
index e9a0d3eceba3..017a1029d35c 100644
--- a/media/tests/AudioPolicyTest/src/com/android/audiopolicytest/AudioManagerTest.java
+++ b/media/tests/AudioPolicyTest/src/com/android/audiopolicytest/AudioManagerTest.java
@@ -16,6 +16,15 @@
 
 package com.android.audiopolicytest;
 
+import static android.media.AudioManager.STREAM_ACCESSIBILITY;
+import static android.media.AudioManager.STREAM_ALARM;
+import static android.media.AudioManager.STREAM_DTMF;
+import static android.media.AudioManager.STREAM_MUSIC;
+import static android.media.AudioManager.STREAM_NOTIFICATION;
+import static android.media.AudioManager.STREAM_RING;
+import static android.media.AudioManager.STREAM_SYSTEM;
+import static android.media.AudioManager.STREAM_VOICE_CALL;
+
 import static androidx.test.core.app.ApplicationProvider.getApplicationContext;
 
 import static com.android.audiopolicytest.AudioVolumeTestUtil.DEFAULT_ATTRIBUTES;
@@ -28,11 +37,15 @@ import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 
+import android.content.Context;
 import android.media.AudioAttributes;
 import android.media.AudioManager;
 import android.media.AudioSystem;
+import android.media.IAudioService;
 import android.media.audiopolicy.AudioProductStrategy;
 import android.media.audiopolicy.AudioVolumeGroup;
+import android.os.IBinder;
+import android.os.ServiceManager;
 import android.platform.test.annotations.Presubmit;
 import android.util.Log;
 
@@ -207,6 +220,32 @@ public class AudioManagerTest {
     }
 
     //-----------------------------------------------------------------
+    // Test getStreamVolume consistency with AudioService
+    //-----------------------------------------------------------------
+    @Test
+    public void getStreamMinMaxVolume_consistentWithAs() throws Exception {
+        IBinder b = ServiceManager.getService(Context.AUDIO_SERVICE);
+        IAudioService service = IAudioService.Stub.asInterface(b);
+        final int[] streamTypes = {
+                STREAM_VOICE_CALL,
+                STREAM_SYSTEM,
+                STREAM_RING,
+                STREAM_MUSIC,
+                STREAM_ALARM,
+                STREAM_NOTIFICATION,
+                STREAM_DTMF,
+                STREAM_ACCESSIBILITY,
+        };
+
+        for (int streamType : streamTypes) {
+            assertEquals(service.getStreamMinVolume(streamType),
+                    mAudioManager.getStreamMinVolume(streamType));
+            assertEquals(service.getStreamMaxVolume(streamType),
+                    mAudioManager.getStreamMaxVolume(streamType));
+        }
+    }
+
+    //-----------------------------------------------------------------
     // Test Volume per Attributes setter/getters
     //-----------------------------------------------------------------
     @Test
diff --git a/services/core/java/com/android/server/audio/AudioManagerShellCommand.java b/services/core/java/com/android/server/audio/AudioManagerShellCommand.java
index 030ce12f5063..c35f4fca6edd 100644
--- a/services/core/java/com/android/server/audio/AudioManagerShellCommand.java
+++ b/services/core/java/com/android/server/audio/AudioManagerShellCommand.java
@@ -65,6 +65,10 @@ class AudioManagerShellCommand extends ShellCommand {
                 return setRingerMode();
             case "set-volume":
                 return setVolume();
+            case "get-min-volume":
+                return getMinVolume();
+            case "get-max-volume":
+                return getMaxVolume();
             case "set-device-volume":
                 return setDeviceVolume();
             case "adj-mute":
@@ -106,6 +110,10 @@ class AudioManagerShellCommand extends ShellCommand {
         pw.println("    Sets the Ringer mode to one of NORMAL|SILENT|VIBRATE");
         pw.println("  set-volume STREAM_TYPE VOLUME_INDEX");
         pw.println("    Sets the volume for STREAM_TYPE to VOLUME_INDEX");
+        pw.println("  get-min-volume STREAM_TYPE");
+        pw.println("    Gets the min volume for STREAM_TYPE");
+        pw.println("  get-max-volume STREAM_TYPE");
+        pw.println("    Gets the max volume for STREAM_TYPE");
         pw.println("  set-device-volume STREAM_TYPE VOLUME_INDEX NATIVE_DEVICE_TYPE");
         pw.println("    Sets for NATIVE_DEVICE_TYPE the STREAM_TYPE volume to VOLUME_INDEX");
         pw.println("  adj-mute STREAM_TYPE");
@@ -296,6 +304,24 @@ class AudioManagerShellCommand extends ShellCommand {
         return 0;
     }
 
+    private int getMinVolume() {
+        final Context context = mService.mContext;
+        final AudioManager am = context.getSystemService(AudioManager.class);
+        final int stream = readIntArg();
+        final int result = am.getStreamMinVolume(stream);
+        getOutPrintWriter().println("AudioManager.getStreamMinVolume(" + stream + ") -> " + result);
+        return 0;
+    }
+
+    private int getMaxVolume() {
+        final Context context = mService.mContext;
+        final AudioManager am = context.getSystemService(AudioManager.class);
+        final int stream = readIntArg();
+        final int result = am.getStreamMaxVolume(stream);
+        getOutPrintWriter().println("AudioManager.getStreamMaxVolume(" + stream + ") -> " + result);
+        return 0;
+    }
+
     private int setDeviceVolume() {
         final Context context = mService.mContext;
         final AudioDeviceVolumeManager advm = (AudioDeviceVolumeManager) context.getSystemService(
diff --git a/services/core/java/com/android/server/audio/AudioService.java b/services/core/java/com/android/server/audio/AudioService.java
index c125d2d2e8cd..1baded86705e 100644
--- a/services/core/java/com/android/server/audio/AudioService.java
+++ b/services/core/java/com/android/server/audio/AudioService.java
@@ -47,9 +47,9 @@ import static android.media.AudioManager.RINGER_MODE_NORMAL;
 import static android.media.AudioManager.RINGER_MODE_SILENT;
 import static android.media.AudioManager.RINGER_MODE_VIBRATE;
 import static android.media.AudioManager.STREAM_SYSTEM;
-import static android.media.IAudioManagerNative.HardeningType;
 import static android.media.audio.Flags.autoPublicVolumeApiHardening;
 import static android.media.audio.Flags.automaticBtDeviceType;
+import static android.media.audio.Flags.cacheGetStreamMinMaxVolume;
 import static android.media.audio.Flags.concurrentAudioRecordBypassPermission;
 import static android.media.audio.Flags.featureSpatialAudioHeadtrackingLowLatency;
 import static android.media.audio.Flags.focusFreezeTestApi;
@@ -4966,6 +4966,8 @@ public class AudioService extends IAudioService.Stub
                 + ringMyCar());
         pw.println("\tandroid.media.audio.Flags.concurrentAudioRecordBypassPermission:"
                 + concurrentAudioRecordBypassPermission());
+        pw.println("\tandroid.media.audio.Flags.cacheGetStreamMinMaxVolume:"
+                + cacheGetStreamMinMaxVolume());
     }
 
     private void dumpAudioMode(PrintWriter pw) {
@@ -9356,6 +9358,12 @@ public class AudioService extends IAudioService.Stub
                     mIndexMinNoPerm = mIndexMin;
                 }
             }
+            if (cacheGetStreamMinMaxVolume() && mStreamType == AudioSystem.STREAM_VOICE_CALL) {
+                if (DEBUG_VOL) {
+                    Log.d(TAG, "Clear min volume cache from updateIndexFactors");
+                }
+                AudioManager.clearVolumeCache(AudioManager.VOLUME_MIN_CACHING_API);
+            }
 
             final int status = AudioSystem.initStreamVolume(
                     mStreamType, indexMinVolCurve, indexMaxVolCurve);
@@ -9393,11 +9401,19 @@ public class AudioService extends IAudioService.Stub
          * @param index minimum index expressed in "UI units", i.e. no 10x factor
          */
         public void updateNoPermMinIndex(int index) {
+            boolean changedNoPermMinIndex =
+                    cacheGetStreamMinMaxVolume() && (index * 10) != mIndexMinNoPerm;
             mIndexMinNoPerm = index * 10;
             if (mIndexMinNoPerm < mIndexMin) {
                 Log.e(TAG, "Invalid mIndexMinNoPerm for stream " + mStreamType);
                 mIndexMinNoPerm = mIndexMin;
             }
+            if (changedNoPermMinIndex) {
+                if (DEBUG_VOL) {
+                    Log.d(TAG, "Clear min volume cache from updateNoPermMinIndex");
+                }
+                AudioManager.clearVolumeCache(AudioManager.VOLUME_MIN_CACHING_API);
+            }
         }
 
         /**
diff --git a/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java b/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java
index ef9580c54de6..8d3eef4a3168 100644
--- a/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java
@@ -38,6 +38,7 @@ import android.media.AudioManager;
 import android.media.AudioSystem;
 import android.media.IAudioDeviceVolumeDispatcher;
 import android.media.VolumeInfo;
+import android.os.IpcDataCache;
 import android.os.PermissionEnforcer;
 import android.os.RemoteException;
 import android.os.test.TestLooper;
@@ -83,6 +84,7 @@ public class AbsoluteVolumeBehaviorTest {
 
     @Before
     public void setUp() throws Exception {
+        IpcDataCache.disableForTestMode();
         mTestLooper = new TestLooper();
 
         mContext = spy(ApplicationProvider.getApplicationContext());
diff --git a/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java b/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java
index 746645a8c585..541dbba67957 100644
--- a/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java
@@ -28,6 +28,7 @@ import android.media.AudioDeviceAttributes;
 import android.media.AudioDeviceInfo;
 import android.media.AudioManager;
 import android.media.IDeviceVolumeBehaviorDispatcher;
+import android.os.IpcDataCache;
 import android.os.PermissionEnforcer;
 import android.os.test.TestLooper;
 import android.platform.test.annotations.Presubmit;
@@ -69,6 +70,7 @@ public class DeviceVolumeBehaviorTest {
 
     @Before
     public void setUp() throws Exception {
+        IpcDataCache.disableForTestMode();
         mTestLooper = new TestLooper();
         mContext = InstrumentationRegistry.getTargetContext();
         mAudioSystem = new NoOpAudioSystemAdapter();
diff --git a/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java b/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java
index 6b41c434b80f..0bbae247d8bb 100644
--- a/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java
@@ -80,6 +80,7 @@ import android.media.AudioSystem;
 import android.media.IDeviceVolumeBehaviorDispatcher;
 import android.media.VolumeInfo;
 import android.media.audiopolicy.AudioVolumeGroup;
+import android.os.IpcDataCache;
 import android.os.Looper;
 import android.os.PermissionEnforcer;
 import android.os.test.TestLooper;
@@ -210,6 +211,8 @@ public class VolumeHelperTest {
 
     @Before
     public void setUp() throws Exception {
+        IpcDataCache.disableForTestMode();
+
         mContext = InstrumentationRegistry.getInstrumentation().getTargetContext();
         mTestLooper = new TestLooper();