diff --git a/core/java/android/os/Binder.java b/core/java/android/os/Binder.java
index f947b5ef9f5be..8b6194c29707b 100644
--- a/core/java/android/os/Binder.java
+++ b/core/java/android/os/Binder.java
@@ -28,6 +28,8 @@ import com.android.internal.util.FastPrintWriter;
 import com.android.internal.util.FunctionalUtils.ThrowingRunnable;
 import com.android.internal.util.FunctionalUtils.ThrowingSupplier;
 
+import dalvik.annotation.optimization.CriticalNative;
+
 import libcore.io.IoUtils;
 import libcore.util.NativeAllocationRegistry;
 
@@ -372,6 +374,54 @@ public class Binder implements IBinder {
      */
     public static final native int getThreadStrictModePolicy();
 
+    /**
+     * Sets the work source for this thread.
+     *
+     * <p>All the following binder calls on this thread will use the provided work source.
+     *
+     * <p>The concept of worksource is similar to {@link WorkSource}. However, for performance
+     * reasons, we only support one UID. This UID represents the original user responsible for the
+     * binder calls.
+     *
+     * <p>A typical use case would be
+     * <pre>
+     * Binder.setThreadWorkSource(uid);
+     * try {
+     *   // Call an API.
+     * } finally {
+     *   Binder.clearThreadWorkSource();
+     * }
+     * </pre>
+     *
+     * @param workSource The original UID responsible for the binder call.
+     * @return The previously set work source.
+     * @hide
+     **/
+    @CriticalNative
+    public static final native int setThreadWorkSource(int workSource);
+
+    /**
+     * Returns the work source set by the caller.
+     *
+     * Unlike {@link Binder#getCallingUid()}, this result of this method cannot be trusted. The
+     * caller can set the value to whatever he wants. Only use this value if you trust the calling
+     * uid.
+     *
+     * @return The original UID responsible for the binder transaction.
+     * @hide
+     */
+    @CriticalNative
+    public static final native int getThreadWorkSource();
+
+    /**
+     * Clears the work source on this thread.
+     *
+     * @return The previously set work source.
+     * @hide
+     **/
+    @CriticalNative
+    public static final native int clearThreadWorkSource();
+
     /**
      * Flush any Binder commands pending in the current thread to the kernel
      * driver.  This can be
diff --git a/core/jni/android_util_Binder.cpp b/core/jni/android_util_Binder.cpp
index d023d22473c84..ec980800c410e 100644
--- a/core/jni/android_util_Binder.cpp
+++ b/core/jni/android_util_Binder.cpp
@@ -904,6 +904,21 @@ static jint android_os_Binder_getThreadStrictModePolicy(JNIEnv* env, jobject cla
     return IPCThreadState::self()->getStrictModePolicy();
 }
 
+static jint android_os_Binder_setThreadWorkSource(jint workSource)
+{
+    return IPCThreadState::self()->setWorkSource(workSource);
+}
+
+static jint android_os_Binder_getThreadWorkSource()
+{
+    return IPCThreadState::self()->getWorkSource();
+}
+
+static jint android_os_Binder_clearThreadWorkSource()
+{
+    return IPCThreadState::self()->clearWorkSource();
+}
+
 static void android_os_Binder_flushPendingCommands(JNIEnv* env, jobject clazz)
 {
     IPCThreadState::self()->flushCommands();
@@ -941,6 +956,12 @@ static const JNINativeMethod gBinderMethods[] = {
     { "restoreCallingIdentity", "(J)V", (void*)android_os_Binder_restoreCallingIdentity },
     { "setThreadStrictModePolicy", "(I)V", (void*)android_os_Binder_setThreadStrictModePolicy },
     { "getThreadStrictModePolicy", "()I", (void*)android_os_Binder_getThreadStrictModePolicy },
+    // @CriticalNative
+    { "setThreadWorkSource", "(I)I", (void*)android_os_Binder_setThreadWorkSource },
+    // @CriticalNative
+    { "getThreadWorkSource", "()I", (void*)android_os_Binder_getThreadWorkSource },
+    // @CriticalNative
+    { "clearThreadWorkSource", "()I", (void*)android_os_Binder_clearThreadWorkSource },
     { "flushPendingCommands", "()V", (void*)android_os_Binder_flushPendingCommands },
     { "getNativeBBinderHolder", "()J", (void*)android_os_Binder_getNativeBBinderHolder },
     { "getNativeFinalizer", "()J", (void*)android_os_Binder_getNativeFinalizer },
diff --git a/core/tests/coretests/src/android/os/BinderTest.java b/core/tests/coretests/src/android/os/BinderTest.java
new file mode 100644
index 0000000000000..1beb598663d1c
--- /dev/null
+++ b/core/tests/coretests/src/android/os/BinderTest.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2018 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.test.suitebuilder.annotation.SmallTest;
+
+import junit.framework.TestCase;
+
+public class BinderTest extends TestCase {
+
+    @SmallTest
+    public void testSetWorkSource() throws Exception {
+        Binder.setThreadWorkSource(100);
+        assertEquals(100, Binder.getThreadWorkSource());
+    }
+
+    @SmallTest
+    public void testClearWorkSource() throws Exception {
+        Binder.setThreadWorkSource(100);
+        Binder.clearThreadWorkSource();
+        assertEquals(-1, Binder.getThreadWorkSource());
+    }
+}