Merge "Update ApplicationStartInfo API" into main

7 files changed, 229 insertions, 98 deletions

diff --git a/core/api/current.txt b/core/api/current.txt
index e157571e2bac..1e2676c86b7a 100644
--- a/core/api/current.txt
+++ b/core/api/current.txt
@@ -4616,7 +4616,9 @@ package android.app {
 
   public class ActivityManager {
     method public int addAppTask(@NonNull android.app.Activity, @NonNull android.content.Intent, @Nullable android.app.ActivityManager.TaskDescription, @NonNull android.graphics.Bitmap);
+    method public void addStartInfoTimestamp(@IntRange(from=android.app.ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_DEVELOPER_START, to=android.app.ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_DEVELOPER) int, long);
     method public void appNotResponding(@NonNull String);
+    method public void clearApplicationStartInfoCompletionListener();
     method public boolean clearApplicationUserData();
     method public void clearWatchHeapLimit();
     method @RequiresPermission(android.Manifest.permission.DUMP) public void dumpPackageState(java.io.FileDescriptor, String);
@@ -4624,6 +4626,7 @@ package android.app {
     method public java.util.List<android.app.ActivityManager.AppTask> getAppTasks();
     method public android.content.pm.ConfigurationInfo getDeviceConfigurationInfo();
     method @NonNull public java.util.List<android.app.ApplicationExitInfo> getHistoricalProcessExitReasons(@Nullable String, @IntRange(from=0) int, @IntRange(from=0) int);
+    method @NonNull public java.util.List<android.app.ApplicationStartInfo> getHistoricalProcessStartReasons(@IntRange(from=0) int);
     method public int getLargeMemoryClass();
     method public int getLauncherLargeIconDensity();
     method public int getLauncherLargeIconSize();
@@ -4650,6 +4653,7 @@ package android.app {
     method @RequiresPermission(android.Manifest.permission.REORDER_TASKS) public void moveTaskToFront(int, int);
     method @RequiresPermission(android.Manifest.permission.REORDER_TASKS) public void moveTaskToFront(int, int, android.os.Bundle);
     method @Deprecated public void restartPackage(String);
+    method public void setApplicationStartInfoCompletionListener(@NonNull java.util.concurrent.Executor, @NonNull java.util.function.Consumer<android.app.ApplicationStartInfo>);
     method public void setProcessStateSummary(@Nullable byte[]);
     method public static void setVrThread(int);
     method public void setWatchHeapLimit(long);
@@ -5230,6 +5234,57 @@ package android.app {
     field public static final int REASON_USER_STOPPED = 11; // 0xb
   }
 
+  public final class ApplicationStartInfo implements android.os.Parcelable {
+    method public int describeContents();
+    method public int getDefiningUid();
+    method @Nullable public android.content.Intent getIntent();
+    method public int getLaunchMode();
+    method public int getPackageUid();
+    method public int getPid();
+    method @NonNull public String getProcessName();
+    method public int getRealUid();
+    method public int getReason();
+    method public int getStartType();
+    method public int getStartupState();
+    method @NonNull public java.util.Map<java.lang.Integer,java.lang.Long> getStartupTimestamps();
+    method public void writeToParcel(@NonNull android.os.Parcel, int);
+    field @NonNull public static final android.os.Parcelable.Creator<android.app.ApplicationStartInfo> CREATOR;
+    field public static final int LAUNCH_MODE_SINGLE_INSTANCE = 2; // 0x2
+    field public static final int LAUNCH_MODE_SINGLE_INSTANCE_PER_TASK = 4; // 0x4
+    field public static final int LAUNCH_MODE_SINGLE_TASK = 3; // 0x3
+    field public static final int LAUNCH_MODE_SINGLE_TOP = 1; // 0x1
+    field public static final int LAUNCH_MODE_STANDARD = 0; // 0x0
+    field public static final int STARTUP_STATE_ERROR = 1; // 0x1
+    field public static final int STARTUP_STATE_FIRST_FRAME_DRAWN = 2; // 0x2
+    field public static final int STARTUP_STATE_STARTED = 0; // 0x0
+    field public static final int START_REASON_ALARM = 0; // 0x0
+    field public static final int START_REASON_BACKUP = 1; // 0x1
+    field public static final int START_REASON_BOOT_COMPLETE = 2; // 0x2
+    field public static final int START_REASON_BROADCAST = 3; // 0x3
+    field public static final int START_REASON_CONTENT_PROVIDER = 4; // 0x4
+    field public static final int START_REASON_JOB = 5; // 0x5
+    field public static final int START_REASON_LAUNCHER = 6; // 0x6
+    field public static final int START_REASON_LAUNCHER_RECENTS = 7; // 0x7
+    field public static final int START_REASON_OTHER = 8; // 0x8
+    field public static final int START_REASON_PUSH = 9; // 0x9
+    field public static final int START_REASON_SERVICE = 10; // 0xa
+    field public static final int START_REASON_START_ACTIVITY = 11; // 0xb
+    field public static final int START_TIMESTAMP_APPLICATION_ONCREATE = 2; // 0x2
+    field public static final int START_TIMESTAMP_BIND_APPLICATION = 3; // 0x3
+    field public static final int START_TIMESTAMP_FIRST_FRAME = 4; // 0x4
+    field public static final int START_TIMESTAMP_FORK = 1; // 0x1
+    field public static final int START_TIMESTAMP_FULLY_DRAWN = 5; // 0x5
+    field public static final int START_TIMESTAMP_INITIAL_RENDERTHREAD_FRAME = 6; // 0x6
+    field public static final int START_TIMESTAMP_LAUNCH = 0; // 0x0
+    field public static final int START_TIMESTAMP_RESERVED_RANGE_DEVELOPER = 30; // 0x1e
+    field public static final int START_TIMESTAMP_RESERVED_RANGE_DEVELOPER_START = 21; // 0x15
+    field public static final int START_TIMESTAMP_RESERVED_RANGE_SYSTEM = 20; // 0x14
+    field public static final int START_TIMESTAMP_SURFACEFLINGER_COMPOSITION_COMPLETE = 7; // 0x7
+    field public static final int START_TYPE_COLD = 0; // 0x0
+    field public static final int START_TYPE_HOT = 2; // 0x2
+    field public static final int START_TYPE_WARM = 1; // 0x1
+  }
+
   public final class AsyncNotedAppOp implements android.os.Parcelable {
     method public int describeContents();
     method @Nullable public String getAttributionTag();
diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index b18584becbb2..fbc759f790f3 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -535,6 +535,7 @@ package android.app {
     method @RequiresPermission(android.Manifest.permission.PACKAGE_USAGE_STATS) public void addOnUidImportanceListener(android.app.ActivityManager.OnUidImportanceListener, int);
     method @RequiresPermission(android.Manifest.permission.FORCE_STOP_PACKAGES) public void forceStopPackage(String);
     method @RequiresPermission(anyOf={"android.permission.INTERACT_ACROSS_USERS", "android.permission.INTERACT_ACROSS_USERS_FULL"}) public static int getCurrentUser();
+    method @NonNull @RequiresPermission(android.Manifest.permission.DUMP) public java.util.List<android.app.ApplicationStartInfo> getExternalHistoricalProcessStartReasons(@NonNull String, @IntRange(from=0) int);
     method @RequiresPermission(android.Manifest.permission.PACKAGE_USAGE_STATS) public int getPackageImportance(String);
     method @NonNull public java.util.Collection<java.util.Locale> getSupportedLocales();
     method @RequiresPermission(android.Manifest.permission.PACKAGE_USAGE_STATS) public int getUidImportance(int);
diff --git a/core/java/android/app/ActivityManager.java b/core/java/android/app/ActivityManager.java
index 37a1e62c8cc0..b4f6d6fe770d 100644
--- a/core/java/android/app/ActivityManager.java
+++ b/core/java/android/app/ActivityManager.java
@@ -72,6 +72,7 @@ import android.os.PowerExemptionManager.ReasonCode;
 import android.os.Process;
 import android.os.RemoteException;
 import android.os.ServiceManager;
+import android.os.SystemClock;
 import android.os.SystemProperties;
 import android.os.UserHandle;
 import android.os.UserManager;
@@ -107,6 +108,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Locale;
 import java.util.concurrent.Executor;
+import java.util.function.Consumer;
 
 /**
  * <p>
@@ -3978,8 +3980,6 @@ public class ActivityManager {
      *
      * @return a list of {@link ApplicationStartInfo} records matching the criteria, sorted in
      *         the order from most recent to least recent.
-     *
-     * @hide
      */
     @NonNull
     public List<ApplicationStartInfo> getHistoricalProcessStartReasons(
@@ -4011,6 +4011,7 @@ public class ActivityManager {
      * @hide
      */
     @NonNull
+    @SystemApi
     @RequiresPermission(Manifest.permission.DUMP)
     public List<ApplicationStartInfo> getExternalHistoricalProcessStartReasons(
             @NonNull String packageName, @IntRange(from = 0) int maxNum) {
@@ -4024,18 +4025,6 @@ public class ActivityManager {
     }
 
     /**
-     * Callback to receive {@link ApplicationStartInfo} object once recording of startup related
-     * metrics is complete.
-     * Use with {@link #setApplicationStartInfoCompleteListener}.
-     *
-     * @hide
-     */
-    public interface ApplicationStartInfoCompleteListener {
-        /** {@link ApplicationStartInfo} is complete, no more info will be added. */
-        void onApplicationStartInfoComplete(@NonNull ApplicationStartInfo applicationStartInfo);
-    }
-
-    /**
      * Sets a callback to be notified when the {@link ApplicationStartInfo} records of this startup
      * are complete.
      *
@@ -4054,19 +4043,16 @@ public class ActivityManager {
      *                    complete. Will replace existing listener if one is already attached.
      *
      * @throws IllegalArgumentException if executor or listener are null.
-     *
-     * @hide
      */
-    public void setApplicationStartInfoCompleteListener(@NonNull final Executor executor,
-            @NonNull final ApplicationStartInfoCompleteListener listener) {
+    public void setApplicationStartInfoCompletionListener(@NonNull final Executor executor,
+            @NonNull final Consumer<ApplicationStartInfo> listener) {
         Preconditions.checkNotNull(executor, "executor cannot be null");
         Preconditions.checkNotNull(listener, "listener cannot be null");
         IApplicationStartInfoCompleteListener callback =
                 new IApplicationStartInfoCompleteListener.Stub() {
             @Override
             public void onApplicationStartInfoComplete(ApplicationStartInfo applicationStartInfo) {
-                executor.execute(() ->
-                        listener.onApplicationStartInfoComplete(applicationStartInfo));
+                executor.execute(() -> listener.accept(applicationStartInfo));
             }
         };
         try {
@@ -4077,13 +4063,42 @@ public class ActivityManager {
     }
 
     /**
-     * Removes the callback set by {@link #setApplicationStartInfoCompleteListener} if there is one.
+     * Removes the callback set by {@link #setApplicationStartInfoCompletionListener} if there is one.
+     */
+    public void clearApplicationStartInfoCompletionListener() {
+        try {
+            getService().clearApplicationStartInfoCompleteListener(mContext.getUserId());
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Adds an optional developer supplied timestamp to the calling apps most recent
+     * {@link ApplicationStartInfo}. This is in addition to system recorded timestamps.
      *
-     * @hide
+     * <p class="note"> Note: timestamps added after {@link Activity#reportFullyDrawn} is called
+     * will be discarded.</p>
+     *
+     * <p class="note"> Note: will overwrite existing timestamp if called with same key.</p>
+     *
+     * @param key         Unique key for timestamp. Must be greater than
+     *                    {@link ApplicationStartInfo#START_TIMESTAMP_RESERVED_RANGE_SYSTEM} and
+     *                    less than or equal to
+     *                    {@link ApplicationStartInfo#START_TIMESTAMP_RESERVED_RANGE_DEVELOPER}.
+     *                    Will thow {@link java.lang.IllegalArgumentException} if not in range.
+     * @param timestampNs Clock monotonic time in nanoseconds of event to be recorded.
      */
-    public void removeApplicationStartInfoCompleteListener() {
+    public void addStartInfoTimestamp(@IntRange(
+            from = ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_DEVELOPER_START,
+            to = ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_DEVELOPER) int key,
+            long timestampNs) {
+        if (key <= ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_SYSTEM
+                || key > ApplicationStartInfo.START_TIMESTAMP_RESERVED_RANGE_DEVELOPER) {
+            throw new IllegalArgumentException("Key not in allowed range.");
+        }
         try {
-            getService().removeApplicationStartInfoCompleteListener(mContext.getUserId());
+            getService().addStartInfoTimestamp(key, timestampNs, mContext.getUserId());
         } catch (RemoteException e) {
             throw e.rethrowFromSystemServer();
         }
diff --git a/core/java/android/app/ApplicationStartInfo.java b/core/java/android/app/ApplicationStartInfo.java
index 5e2a4ca441a0..f5fb6edfcc04 100644
--- a/core/java/android/app/ApplicationStartInfo.java
+++ b/core/java/android/app/ApplicationStartInfo.java
@@ -21,20 +21,21 @@ import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.annotation.SuppressLint;
 import android.content.Intent;
+import android.icu.text.SimpleDateFormat;
 import android.os.Parcel;
 import android.os.Parcelable;
+import android.os.UserHandle;
+import android.util.ArrayMap;
 
-import java.lang.annotation.ElementType;
+import java.io.PrintWriter;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-import java.util.HashMap;
+import java.util.Iterator;
 import java.util.Map;
+import java.util.Set;
 
 /**
  * Provide information related to a processes startup.
- *
- * @hide
  */
 public final class ApplicationStartInfo implements Parcelable {
 
@@ -78,14 +79,14 @@ public final class ApplicationStartInfo implements Parcelable {
     /** Process started due to click app icon or widget from launcher. */
     public static final int START_REASON_LAUNCHER = 6;
 
+    /** Process started from launcher recents. */
+    public static final int START_REASON_LAUNCHER_RECENTS = 7;
+
     /** Process started not for any of the listed reasons. */
-    public static final int START_REASON_OTHER = 7;
+    public static final int START_REASON_OTHER = 8;
 
     /** Process started due to push message. */
-    public static final int START_REASON_PUSH = 8;
-
-    /** Process started to resume activity. */
-    public static final int START_REASON_RESUMED_ACTIVITY = 9;
+    public static final int START_REASON_PUSH = 9;
 
     /** Process service started. */
     public static final int START_REASON_SERVICE = 10;
@@ -136,11 +137,21 @@ public final class ApplicationStartInfo implements Parcelable {
      */
     public static final int LAUNCH_MODE_SINGLE_INSTANCE_PER_TASK = 4;
 
+    /** The end of the range, beginning with 0, reserved for system timestamps.*/
+    public static final int START_TIMESTAMP_RESERVED_RANGE_SYSTEM = 20;
+
+    /** The beginning of the range reserved for developer supplied timestamps.*/
+    public static final int START_TIMESTAMP_RESERVED_RANGE_DEVELOPER_START =
+            START_TIMESTAMP_RESERVED_RANGE_SYSTEM + 1;
+
+    /** The end of the range reserved for developer supplied timestamps.*/
+    public static final int START_TIMESTAMP_RESERVED_RANGE_DEVELOPER = 30;
+
     /** Clock monotonic timestamp of launch started. */
     public static final int START_TIMESTAMP_LAUNCH = 0;
 
-    /** Clock monotonic timestamp of finish java classloading. */
-    public static final int START_TIMESTAMP_JAVA_CLASSLOADING_COMPLETE = 1;
+    /** Clock monotonic timestamp of process fork. */
+    public static final int START_TIMESTAMP_FORK = 1;
 
     /** Clock monotonic timestamp of Application onCreate called. */
     public static final int START_TIMESTAMP_APPLICATION_ONCREATE = 2;
@@ -154,6 +165,12 @@ public final class ApplicationStartInfo implements Parcelable {
     /** Clock monotonic timestamp of reportFullyDrawn called by application. */
     public static final int START_TIMESTAMP_FULLY_DRAWN = 5;
 
+    /** Clock monotonic timestamp of initial renderthread frame. */
+    public static final int START_TIMESTAMP_INITIAL_RENDERTHREAD_FRAME = 6;
+
+    /** Clock monotonic timestamp of surfaceflinger composition complete. */
+    public static final int START_TIMESTAMP_SURFACEFLINGER_COMPOSITION_COMPLETE = 7;
+
     /**
      * @see #getStartupState
      */
@@ -192,7 +209,7 @@ public final class ApplicationStartInfo implements Parcelable {
     /**
      * @see #getStartupTimestamps
      */
-    private Map<@StartupTimestamp Integer, Long> mStartupTimestampsNs;
+    private ArrayMap<Integer, Long> mStartupTimestampsNs;
 
     /**
      * @see #getStartType
@@ -235,9 +252,9 @@ public final class ApplicationStartInfo implements Parcelable {
                 START_REASON_CONTENT_PROVIDER,
                 START_REASON_JOB,
                 START_REASON_LAUNCHER,
+                START_REASON_LAUNCHER_RECENTS,
                 START_REASON_OTHER,
                 START_REASON_PUSH,
-                START_REASON_RESUMED_ACTIVITY,
                 START_REASON_SERVICE,
                 START_REASON_START_ACTIVITY,
             })
@@ -273,22 +290,6 @@ public final class ApplicationStartInfo implements Parcelable {
     public @interface LaunchMode {}
 
     /**
-     * @hide *
-     */
-    @IntDef(
-            prefix = {"START_TIMESTAMP_"},
-            value = {
-                START_TIMESTAMP_LAUNCH,
-                START_TIMESTAMP_JAVA_CLASSLOADING_COMPLETE,
-                START_TIMESTAMP_APPLICATION_ONCREATE,
-                START_TIMESTAMP_BIND_APPLICATION,
-                START_TIMESTAMP_FULLY_DRAWN,
-            })
-    @Retention(RetentionPolicy.SOURCE)
-    @Target({ElementType.TYPE_PARAMETER, ElementType.TYPE_USE})
-    public @interface StartupTimestamp {}
-
-    /**
      * @see #getStartupState
      * @hide
      */
@@ -348,9 +349,12 @@ public final class ApplicationStartInfo implements Parcelable {
      * @see #getStartupTimestamps
      * @hide
      */
-    public void addStartupTimestamp(@StartupTimestamp int key, long timestampNs) {
+    public void addStartupTimestamp(int key, long timestampNs) {
+        if (key < 0 || key > START_TIMESTAMP_RESERVED_RANGE_DEVELOPER) {
+            return;
+        }
         if (mStartupTimestampsNs == null) {
-            mStartupTimestampsNs = new HashMap<@StartupTimestamp Integer, Long>();
+            mStartupTimestampsNs = new ArrayMap<Integer, Long>();
         }
         mStartupTimestampsNs.put(key, timestampNs);
     }
@@ -475,9 +479,9 @@ public final class ApplicationStartInfo implements Parcelable {
      * dependant on devloper calling {@link Activity#reportFullyDrawn}.
      * </p>
      */
-    public @NonNull Map<@StartupTimestamp Integer, Long> getStartupTimestamps() {
+    public @NonNull Map<Integer, Long> getStartupTimestamps() {
         if (mStartupTimestampsNs == null) {
-            mStartupTimestampsNs = new HashMap<@StartupTimestamp Integer, Long>();
+            mStartupTimestampsNs = new ArrayMap<Integer, Long>();
         }
         return mStartupTimestampsNs;
     }
@@ -536,9 +540,12 @@ public final class ApplicationStartInfo implements Parcelable {
         dest.writeString(mProcessName);
         dest.writeInt(mReason);
         dest.writeInt(mStartupTimestampsNs.size());
-        for (@StartupTimestamp int key : mStartupTimestampsNs.keySet()) {
-            dest.writeInt(key);
-            dest.writeLong(mStartupTimestampsNs.get(key));
+        Set<Map.Entry<Integer, Long>> timestampEntrySet = mStartupTimestampsNs.entrySet();
+        Iterator<Map.Entry<Integer, Long>> iter = timestampEntrySet.iterator();
+        while (iter.hasNext()) {
+            Map.Entry<Integer, Long> entry = iter.next();
+            dest.writeInt(entry.getKey());
+            dest.writeLong(entry.getValue());
         }
         dest.writeInt(mStartType);
         dest.writeParcelable(mStartIntent, flags);
@@ -599,4 +606,67 @@ public final class ApplicationStartInfo implements Parcelable {
                     return new ApplicationStartInfo[size];
                 }
             };
+
+    /** @hide */
+    public void dump(@NonNull PrintWriter pw, @Nullable String prefix, @Nullable String seqSuffix,
+            @NonNull SimpleDateFormat sdf) {
+        StringBuilder sb = new StringBuilder();
+        sb.append(prefix)
+                .append("ApplicationStartInfo ").append(seqSuffix).append(':')
+                .append('\n')
+                .append(" pid=").append(mPid)
+                .append(" realUid=").append(mRealUid)
+                .append(" packageUid=").append(mPackageUid)
+                .append(" definingUid=").append(mDefiningUid)
+                .append(" user=").append(UserHandle.getUserId(mPackageUid))
+                .append('\n')
+                .append(" process=").append(mProcessName)
+                .append(" startupState=").append(mStartupState)
+                .append(" reason=").append(reasonToString(mReason))
+                .append(" startType=").append(startTypeToString(mStartType))
+                .append(" launchMode=").append(mLaunchMode)
+                .append('\n');
+        if (mStartIntent != null) {
+            sb.append(" intent=").append(mStartIntent.toString())
+                .append('\n');
+        }
+        if (mStartupTimestampsNs.size() > 0) {
+            sb.append(" timestamps: ");
+            Set<Map.Entry<Integer, Long>> timestampEntrySet = mStartupTimestampsNs.entrySet();
+            Iterator<Map.Entry<Integer, Long>> iter = timestampEntrySet.iterator();
+            while (iter.hasNext()) {
+                Map.Entry<Integer, Long> entry = iter.next();
+                sb.append(entry.getKey()).append("=").append(entry.getValue()).append(" ");
+            }
+            sb.append('\n');
+        }
+        pw.print(sb.toString());
+    }
+
+    private static String reasonToString(@StartReason int reason) {
+        return switch (reason) {
+            case START_REASON_ALARM -> "ALARM";
+            case START_REASON_BACKUP -> "BACKUP";
+            case START_REASON_BOOT_COMPLETE -> "BOOT COMPLETE";
+            case START_REASON_BROADCAST -> "BROADCAST";
+            case START_REASON_CONTENT_PROVIDER -> "CONTENT PROVIDER";
+            case START_REASON_JOB -> "JOB";
+            case START_REASON_LAUNCHER -> "LAUNCHER";
+            case START_REASON_LAUNCHER_RECENTS -> "LAUNCHER RECENTS";
+            case START_REASON_OTHER -> "OTHER";
+            case START_REASON_PUSH -> "PUSH";
+            case START_REASON_SERVICE -> "SERVICE";
+            case START_REASON_START_ACTIVITY -> "START ACTIVITY";
+            default -> "";
+        };
+    }
+
+    private static String startTypeToString(@StartType int startType) {
+        return switch (startType) {
+            case START_TYPE_COLD -> "COLD";
+            case START_TYPE_WARM -> "WARM";
+            case START_TYPE_HOT -> "HOT";
+            default -> "";
+        };
+    }
 }
diff --git a/core/java/android/app/IActivityManager.aidl b/core/java/android/app/IActivityManager.aidl
index a8b1688cc43b..03baf2671314 100644
--- a/core/java/android/app/IActivityManager.aidl
+++ b/core/java/android/app/IActivityManager.aidl
@@ -724,7 +724,20 @@ interface IActivityManager {
      *
      * @param userId      The userId in the multi-user environment.
      */
-    void removeApplicationStartInfoCompleteListener(int userId);
+    void clearApplicationStartInfoCompleteListener(int userId);
+
+
+    /**
+     * Adds a timestamp of the moment called to the calling apps most recent
+     * {@link ApplicationStartInfo}.
+     *
+     *
+     * @param key         Unique key for timestamp.
+     * @param timestampNs Clock monotonic time in nanoseconds of event to be
+     *                    recorded.
+     * @param userId      The userId in the multi-user environment.
+     */
+    void addStartInfoTimestamp(int key, long timestampNs, int userId);
 
     /**
      * Return a list of {@link ApplicationExitInfo} records.
diff --git a/services/core/java/com/android/server/am/ActivityManagerConstants.java b/services/core/java/com/android/server/am/ActivityManagerConstants.java
index 03e86914e121..bef53c7f31ee 100644
--- a/services/core/java/com/android/server/am/ActivityManagerConstants.java
+++ b/services/core/java/com/android/server/am/ActivityManagerConstants.java
@@ -287,10 +287,6 @@ final class ActivityManagerConstants extends ContentObserver {
       */
     private static final String KEY_LOW_SWAP_THRESHOLD_PERCENT = "low_swap_threshold_percent";
 
-    /** Default value for mFlagApplicationStartInfoEnabled. Defaults to false. */
-    private static final String KEY_DEFAULT_APPLICATION_START_INFO_ENABLED =
-            "enable_app_start_info";
-
     /**
      * Default value for mFlagBackgroundActivityStartsEnabled if not explicitly set in
      * Settings.Global. This allows it to be set experimentally unless it has been
@@ -596,9 +592,6 @@ final class ActivityManagerConstants extends ContentObserver {
     // Controlled by Settings.Global.ACTIVITY_STARTS_LOGGING_ENABLED
     volatile boolean mFlagActivityStartsLoggingEnabled;
 
-    // Indicates whether ApplicationStartInfo is enabled.
-    volatile boolean mFlagApplicationStartInfoEnabled;
-
     // Indicates whether the background activity starts is enabled.
     // Controlled by Settings.Global.BACKGROUND_ACTIVITY_STARTS_ENABLED.
     // If not set explicitly the default is controlled by DeviceConfig.
@@ -1070,9 +1063,6 @@ final class ActivityManagerConstants extends ContentObserver {
                             case KEY_MAX_CACHED_PROCESSES:
                                 updateMaxCachedProcesses();
                                 break;
-                            case KEY_DEFAULT_APPLICATION_START_INFO_ENABLED:
-                                updateApplicationStartInfoEnabled();
-                                break;
                             case KEY_DEFAULT_BACKGROUND_ACTIVITY_STARTS_ENABLED:
                                 updateBackgroundActivityStarts();
                                 break;
@@ -1493,14 +1483,6 @@ final class ActivityManagerConstants extends ContentObserver {
                 Settings.Global.ACTIVITY_STARTS_LOGGING_ENABLED, 1) == 1;
     }
 
-    private void updateApplicationStartInfoEnabled() {
-        mFlagApplicationStartInfoEnabled =
-                DeviceConfig.getBoolean(
-                        DeviceConfig.NAMESPACE_ACTIVITY_MANAGER,
-                        KEY_DEFAULT_APPLICATION_START_INFO_ENABLED,
-                        /*defaultValue*/ false);
-    }
-
     private void updateBackgroundActivityStarts() {
         mFlagBackgroundActivityStartsEnabled = DeviceConfig.getBoolean(
                 DeviceConfig.NAMESPACE_ACTIVITY_MANAGER,
@@ -2125,10 +2107,6 @@ final class ActivityManagerConstants extends ContentObserver {
         pw.println(mFgToBgFgsGraceDuration);
         pw.print("  "); pw.print(KEY_FGS_START_FOREGROUND_TIMEOUT); pw.print("=");
         pw.println(mFgsStartForegroundTimeoutMs);
-        pw.print("  ");
-        pw.print(KEY_DEFAULT_APPLICATION_START_INFO_ENABLED);
-        pw.print("=");
-        pw.println(mFlagApplicationStartInfoEnabled);
         pw.print("  "); pw.print(KEY_DEFAULT_BACKGROUND_ACTIVITY_STARTS_ENABLED); pw.print("=");
         pw.println(mFlagBackgroundActivityStartsEnabled);
         pw.print("  "); pw.print(KEY_DEFAULT_BACKGROUND_FGS_STARTS_RESTRICTION_ENABLED);
diff --git a/services/core/java/com/android/server/am/ActivityManagerService.java b/services/core/java/com/android/server/am/ActivityManagerService.java
index 132d6a9d743f..a0fae26fcac1 100644
--- a/services/core/java/com/android/server/am/ActivityManagerService.java
+++ b/services/core/java/com/android/server/am/ActivityManagerService.java
@@ -9563,14 +9563,9 @@ public class ActivityManagerService extends IActivityManager.Stub
         return retList;
     }
 
-    /* @hide */
     @Override
     public ParceledListSlice<ApplicationStartInfo> getHistoricalProcessStartReasons(
             String packageName, int maxNum, int userId) {
-        if (!mConstants.mFlagApplicationStartInfoEnabled) {
-            return new ParceledListSlice<ApplicationStartInfo>(
-                new ArrayList<ApplicationStartInfo>());
-        }
         enforceNotIsolatedCaller("getHistoricalProcessStartReasons");
 
         final ArrayList<ApplicationStartInfo> results = new ArrayList<ApplicationStartInfo>();
@@ -9579,24 +9574,28 @@ public class ActivityManagerService extends IActivityManager.Stub
     }
 
 
-    /* @hide */
     @Override
     public void setApplicationStartInfoCompleteListener(
             IApplicationStartInfoCompleteListener listener, int userId) {
-        if (!mConstants.mFlagApplicationStartInfoEnabled) {
-            return;
-        }
         enforceNotIsolatedCaller("setApplicationStartInfoCompleteListener");
     }
 
 
-    /* @hide */
     @Override
-    public void removeApplicationStartInfoCompleteListener(int userId) {
-        if (!mConstants.mFlagApplicationStartInfoEnabled) {
-            return;
+    public void clearApplicationStartInfoCompleteListener(int userId) {
+        enforceNotIsolatedCaller("clearApplicationStartInfoCompleteListener");
+
+        // For the simplification, we don't support USER_ALL nor USER_CURRENT here.
+        if (userId == UserHandle.USER_ALL || userId == UserHandle.USER_CURRENT) {
+            throw new IllegalArgumentException("Unsupported userId");
         }
-        enforceNotIsolatedCaller("removeApplicationStartInfoCompleteListener");
+
+        final int callingUid = Binder.getCallingUid();
+    }
+
+    @Override
+    public void addStartInfoTimestamp(int key, long timestampNs, int userId) {
+        enforceNotIsolatedCaller("addStartInfoTimestamp");
     }
 
     @Override