diff --git a/core/api/current.txt b/core/api/current.txt
index 90546d82..ac7e6cc 100644
--- a/core/api/current.txt
+++ b/core/api/current.txt
@@ -33914,7 +33914,6 @@
 
   @FlaggedApi("android.os.adpf_gpu_report_actual_work_duration") public final class WorkDuration implements android.os.Parcelable {
     ctor public WorkDuration();
-    ctor public WorkDuration(long, long, long, long);
     method public int describeContents();
     method public long getActualCpuDurationNanos();
     method public long getActualGpuDurationNanos();
diff --git a/core/java/android/os/PerformanceHintManager.java b/core/java/android/os/PerformanceHintManager.java
index 37bde3d..746278f 100644
--- a/core/java/android/os/PerformanceHintManager.java
+++ b/core/java/android/os/PerformanceHintManager.java
@@ -204,7 +204,7 @@
         }
 
         /**
-         * Updates this session's target duration for each cycle of work.
+         * Updates this session's target total duration for each cycle of work.
          *
          * @param targetDurationNanos the new desired duration in nanoseconds
          */
diff --git a/core/java/android/os/WorkDuration.java b/core/java/android/os/WorkDuration.java
index 4fdc34f..2ebcd83 100644
--- a/core/java/android/os/WorkDuration.java
+++ b/core/java/android/os/WorkDuration.java
@@ -26,7 +26,7 @@
  * in each component, see
  * {@link PerformanceHintManager.Session#reportActualWorkDuration(WorkDuration)}.
  *
- * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+ * All timings should be in {@link SystemClock#uptimeNanos()} and measured in wall time.
  */
 @FlaggedApi(Flags.FLAG_ADPF_GPU_REPORT_ACTUAL_WORK_DURATION)
 public final class WorkDuration implements Parcelable {
@@ -50,17 +50,9 @@
 
     public WorkDuration() {}
 
-    public WorkDuration(long workPeriodStartTimestampNanos,
-                      long actualTotalDurationNanos,
-                      long actualCpuDurationNanos,
-                      long actualGpuDurationNanos) {
-        mWorkPeriodStartTimestampNanos = workPeriodStartTimestampNanos;
-        mActualTotalDurationNanos = actualTotalDurationNanos;
-        mActualCpuDurationNanos = actualCpuDurationNanos;
-        mActualGpuDurationNanos = actualGpuDurationNanos;
-    }
-
     /**
+     * Constructor for testing.
+     *
      * @hide
      */
     public WorkDuration(long workPeriodStartTimestampNanos,
@@ -86,7 +78,7 @@
     /**
      * Sets the work period start timestamp in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public void setWorkPeriodStartTimestampNanos(long workPeriodStartTimestampNanos) {
         if (workPeriodStartTimestampNanos <= 0) {
@@ -99,7 +91,7 @@
     /**
      * Sets the actual total duration in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public void setActualTotalDurationNanos(long actualTotalDurationNanos) {
         if (actualTotalDurationNanos <= 0) {
@@ -111,7 +103,7 @@
     /**
      * Sets the actual CPU duration in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public void setActualCpuDurationNanos(long actualCpuDurationNanos) {
         if (actualCpuDurationNanos <= 0) {
@@ -123,7 +115,7 @@
     /**
      * Sets the actual GPU duration in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public void setActualGpuDurationNanos(long actualGpuDurationNanos) {
         if (actualGpuDurationNanos < 0) {
@@ -135,7 +127,7 @@
     /**
      * Returns the work period start timestamp based in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public long getWorkPeriodStartTimestampNanos() {
         return mWorkPeriodStartTimestampNanos;
@@ -144,7 +136,7 @@
     /**
      * Returns the actual total duration in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public long getActualTotalDurationNanos() {
         return mActualTotalDurationNanos;
@@ -153,7 +145,7 @@
     /**
      * Returns the actual CPU duration in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public long getActualCpuDurationNanos() {
         return mActualCpuDurationNanos;
@@ -162,7 +154,7 @@
     /**
      * Returns the actual GPU duration in nanoseconds.
      *
-     * All timings should be in {@link SystemClock#elapsedRealtimeNanos()}.
+     * All timings should be in {@link SystemClock#uptimeNanos()}.
      */
     public long getActualGpuDurationNanos() {
         return mActualGpuDurationNanos;
diff --git a/core/tests/coretests/src/android/os/PerformanceHintManagerTest.java b/core/tests/coretests/src/android/os/PerformanceHintManagerTest.java
index 12a2844..a28bb69 100644
--- a/core/tests/coretests/src/android/os/PerformanceHintManagerTest.java
+++ b/core/tests/coretests/src/android/os/PerformanceHintManagerTest.java
@@ -195,9 +195,30 @@
         Session s = createSession();
         assumeNotNull(s);
         s.updateTargetWorkDuration(16);
-        s.reportActualWorkDuration(new WorkDuration(1, 12, 8, 6));
-        s.reportActualWorkDuration(new WorkDuration(1, 33, 14, 20));
-        s.reportActualWorkDuration(new WorkDuration(1, 14, 10, 6));
+        {
+            WorkDuration workDuration = new WorkDuration();
+            workDuration.setWorkPeriodStartTimestampNanos(1);
+            workDuration.setActualTotalDurationNanos(12);
+            workDuration.setActualCpuDurationNanos(8);
+            workDuration.setActualGpuDurationNanos(6);
+            s.reportActualWorkDuration(workDuration);
+        }
+        {
+            WorkDuration workDuration = new WorkDuration();
+            workDuration.setWorkPeriodStartTimestampNanos(1);
+            workDuration.setActualTotalDurationNanos(33);
+            workDuration.setActualCpuDurationNanos(14);
+            workDuration.setActualGpuDurationNanos(20);
+            s.reportActualWorkDuration(workDuration);
+        }
+        {
+            WorkDuration workDuration = new WorkDuration();
+            workDuration.setWorkPeriodStartTimestampNanos(1);
+            workDuration.setActualTotalDurationNanos(14);
+            workDuration.setActualCpuDurationNanos(10);
+            workDuration.setActualGpuDurationNanos(6);
+            s.reportActualWorkDuration(workDuration);
+        }
     }
 
     @Test
@@ -206,25 +227,25 @@
         assumeNotNull(s);
         s.updateTargetWorkDuration(16);
         assertThrows(IllegalArgumentException.class, () -> {
-            s.reportActualWorkDuration(new WorkDuration(-1, 12, 8, 6));
+            s.reportActualWorkDuration(new WorkDuration(-1, 12, 8, 6, 1));
         });
         assertThrows(IllegalArgumentException.class, () -> {
-            s.reportActualWorkDuration(new WorkDuration(0, 12, 8, 6));
+            s.reportActualWorkDuration(new WorkDuration(0, 12, 8, 6, 1));
         });
         assertThrows(IllegalArgumentException.class, () -> {
-            s.reportActualWorkDuration(new WorkDuration(1, -1, 8, 6));
+            s.reportActualWorkDuration(new WorkDuration(1, -1, 8, 6, 1));
         });
         assertThrows(IllegalArgumentException.class, () -> {
-            s.reportActualWorkDuration(new WorkDuration(1, 0, 8, 6));
+            s.reportActualWorkDuration(new WorkDuration(1, 0, 8, 6, 1));
         });
         assertThrows(IllegalArgumentException.class, () -> {
-            s.reportActualWorkDuration(new WorkDuration(1, 12, -1, 6));
+            s.reportActualWorkDuration(new WorkDuration(1, 12, -1, 6, 1));
         });
         assertThrows(IllegalArgumentException.class, () -> {
-            s.reportActualWorkDuration(new WorkDuration(1, 12, 0, 6));
+            s.reportActualWorkDuration(new WorkDuration(1, 12, 0, 6, 1));
         });
         assertThrows(IllegalArgumentException.class, () -> {
-            s.reportActualWorkDuration(new WorkDuration(1, 12, 8, -1));
+            s.reportActualWorkDuration(new WorkDuration(1, 12, 8, -1, 1));
         });
     }
 }
diff --git a/core/tests/coretests/src/android/os/WorkDurationUnitTest.java b/core/tests/coretests/src/android/os/WorkDurationUnitTest.java
new file mode 100644
index 0000000..c70da6e
--- /dev/null
+++ b/core/tests/coretests/src/android/os/WorkDurationUnitTest.java
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2023 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 static org.junit.Assert.assertThrows;
+
+import android.platform.test.annotations.IgnoreUnderRavenwood;
+import android.platform.test.annotations.RequiresFlagsEnabled;
+import android.platform.test.flag.junit.CheckFlagsRule;
+import android.platform.test.flag.junit.DeviceFlagsValueProvider;
+import android.platform.test.ravenwood.RavenwoodRule;
+
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.MockitoAnnotations;
+
+@RunWith(AndroidJUnit4.class)
+@IgnoreUnderRavenwood(blockedBy = WorkDuration.class)
+public class WorkDurationUnitTest {
+    @Rule
+    public final RavenwoodRule mRavenwood = new RavenwoodRule();
+
+    // Required for RequiresFlagsEnabled and RequiresFlagsDisabled annotations to take effect.
+    @Rule
+    public final CheckFlagsRule mCheckFlagsRule = RavenwoodRule.isUnderRavenwood() ? null
+            : DeviceFlagsValueProvider.createCheckFlagsRule();
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+    }
+
+    @Test
+    @RequiresFlagsEnabled(Flags.FLAG_ADPF_GPU_REPORT_ACTUAL_WORK_DURATION)
+    public void testWorkDurationSetters_IllegalArgument() {
+        WorkDuration workDuration = new WorkDuration();
+        assertThrows(IllegalArgumentException.class, () -> {
+            workDuration.setWorkPeriodStartTimestampNanos(-1);
+        });
+        assertThrows(IllegalArgumentException.class, () -> {
+            workDuration.setWorkPeriodStartTimestampNanos(0);
+        });
+        assertThrows(IllegalArgumentException.class, () -> {
+            workDuration.setActualTotalDurationNanos(-1);
+        });
+        assertThrows(IllegalArgumentException.class, () -> {
+            workDuration.setActualTotalDurationNanos(0);
+        });
+        assertThrows(IllegalArgumentException.class, () -> {
+            workDuration.setActualCpuDurationNanos(-1);
+        });
+        assertThrows(IllegalArgumentException.class, () -> {
+            workDuration.setActualCpuDurationNanos(0);
+        });
+        assertThrows(IllegalArgumentException.class, () -> {
+            workDuration.setActualGpuDurationNanos(-1);
+        });
+    }
+}