From 4efb646252c10d0193ecdf98dc6c2d22f7ed0be0 Mon Sep 17 00:00:00 2001
From: Orion Hodson <oth@google.com>
Date: Tue, 20 Dec 2022 15:57:19 +0000
Subject: [PATCH] Reduce Integer allocations in ThreadLocalWorkSource

The code was allocating an Integer for each call of
ThreadLocalWorkSource.setUid().

Bug: 262916014
Test: atest binderLibTest BinderWorkSourceTest BinderProxyTest
Test: atest BinderCallsStatsServiceTest android.os.ParcelTest
Change-Id: I75ece3262bdebaf9d58aee9c355d22121ae09a40
---
 core/java/android/os/ThreadLocalWorkSource.java | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/core/java/android/os/ThreadLocalWorkSource.java b/core/java/android/os/ThreadLocalWorkSource.java
index 894b1cc475b0e..e9adb209ddc6d 100644
--- a/core/java/android/os/ThreadLocalWorkSource.java
+++ b/core/java/android/os/ThreadLocalWorkSource.java
@@ -39,8 +39,8 @@ package android.os;
  */
 public final class ThreadLocalWorkSource {
     public static final int UID_NONE = Message.UID_NONE;
-    private static final ThreadLocal<Integer> sWorkSourceUid =
-            ThreadLocal.withInitial(() -> UID_NONE);
+    private static final ThreadLocal<int []> sWorkSourceUid =
+            ThreadLocal.withInitial(() -> new int[] {UID_NONE});
 
     /**
      * Returns the UID to blame for the code currently executed on this thread.
@@ -50,7 +50,7 @@ public final class ThreadLocalWorkSource {
      * <p>It can also be set manually using {@link #setUid(int)}.
      */
     public static int getUid() {
-        return sWorkSourceUid.get();
+        return sWorkSourceUid.get()[0];
     }
 
     /**
@@ -65,7 +65,7 @@ public final class ThreadLocalWorkSource {
      */
     public static long setUid(int uid) {
         final long token = getToken();
-        sWorkSourceUid.set(uid);
+        sWorkSourceUid.get()[0] = uid;
         return token;
     }
 
@@ -73,7 +73,7 @@ public final class ThreadLocalWorkSource {
      * Restores the state using the provided token.
      */
     public static void restore(long token) {
-        sWorkSourceUid.set(parseUidFromToken(token));
+        sWorkSourceUid.get()[0] = parseUidFromToken(token);
     }
 
     /**
@@ -88,7 +88,7 @@ public final class ThreadLocalWorkSource {
      * </pre>
      *
      * @return a token that can be used to restore the state.
-     **/
+     */
     public static long clear() {
         return setUid(UID_NONE);
     }
@@ -98,7 +98,7 @@ public final class ThreadLocalWorkSource {
     }
 
     private static long getToken() {
-        return sWorkSourceUid.get();
+        return sWorkSourceUid.get()[0];
     }
 
     private ThreadLocalWorkSource() {