Fix AppStartInfo add timestamp bug

Timestamp was being added to the last record, but records are kept sorted newest to oldest so change it to add to first record.

Also added some comments and debug logs.

Bug: 338125667
Test: while logging each timestamp, compare reocrds list before and after start, manually confirm it was attached to the correct record
Flag: EXEMPT - day-to-day bugfix
Change-Id: I1aefe787ec2ba5a1df39f7cd65c0de481b0c5296

1 files changed, 24 insertions, 5 deletions

diff --git a/services/core/java/com/android/server/am/AppStartInfoTracker.java b/services/core/java/com/android/server/am/AppStartInfoTracker.java
index 376f65438e64..2cdf596753fc 100644
--- a/services/core/java/com/android/server/am/AppStartInfoTracker.java
+++ b/services/core/java/com/android/server/am/AppStartInfoTracker.java
@@ -74,6 +74,7 @@ import java.util.function.BiFunction;
 /** A class to manage all the {@link android.app.ApplicationStartInfo} records. */
 public final class AppStartInfoTracker {
     private static final String TAG = TAG_WITH_CLASS_NAME ? "AppStartInfoTracker" : TAG_AM;
+    private static final boolean DEBUG = false;
 
     /** Interval of persisting the app start info to persistent storage. */
     private static final long APP_START_INFO_PERSIST_INTERVAL = TimeUnit.MINUTES.toMillis(30);
@@ -504,6 +505,10 @@ public final class AppStartInfoTracker {
             AppStartInfoContainer container = mData.get(packageName, uid);
             if (container == null) {
                 // Record was not created, discard new data.
+                if (DEBUG) {
+                    Slog.d(TAG, "No container found for package=" + packageName + " and uid=" + uid
+                            + ". Discarding timestamp key=" + key + " val=" + timeNs);
+                }
                 return;
             }
             container.addTimestampToStartLocked(key, timeNs);
@@ -1121,12 +1126,26 @@ public final class AppStartInfoTracker {
 
         @GuardedBy("mLock")
         void addTimestampToStartLocked(int key, long timestampNs) {
-            int index = mInfos.size() - 1;
-            int startupState = mInfos.get(index).getStartupState();
-            if (startupState == ApplicationStartInfo.STARTUP_STATE_STARTED
-                    || key == ApplicationStartInfo.START_TIMESTAMP_FULLY_DRAWN) {
-                mInfos.get(index).addStartupTimestamp(key, timestampNs);
+            // Records are sorted newest to oldest, grab record at index 0.
+            int startupState = mInfos.get(0).getStartupState();
+
+            // If startup state is error then don't accept any further timestamps.
+            if (startupState == ApplicationStartInfo.STARTUP_STATE_ERROR) {
+                if (DEBUG) Slog.d(TAG, "Startup state is error, not accepting new timestamps.");
+                return;
+            }
+
+            // If startup state is first frame drawn then only accept fully drawn timestamp.
+            if (startupState == ApplicationStartInfo.STARTUP_STATE_FIRST_FRAME_DRAWN
+                    && key != ApplicationStartInfo.START_TIMESTAMP_FULLY_DRAWN) {
+                if (DEBUG) {
+                    Slog.d(TAG, "Startup state is first frame drawn and timestamp is not fully "
+                            + "drawn, not accepting new timestamps.");
+                }
+                return;
             }
+
+            mInfos.get(0).addStartupTimestamp(key, timestampNs);
         }
 
         @GuardedBy("mLock")