diff --git a/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.CompletionPort.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.CompletionPort.cs
new file mode 100644
index 000000000000..326f0e9df005
--- /dev/null
+++ b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.CompletionPort.cs
@@ -0,0 +1,23 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+internal partial class Interop
+{
+    internal partial class Kernel32
+    {
+        [DllImport(Libraries.Kernel32, SetLastError = true)]
+        internal static extern IntPtr CreateIoCompletionPort(IntPtr FileHandle, IntPtr ExistingCompletionPort, UIntPtr CompletionKey, int NumberOfConcurrentThreads);
+
+        [DllImport(Libraries.Kernel32, SetLastError = true)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static extern bool PostQueuedCompletionStatus(IntPtr CompletionPort, int dwNumberOfBytesTransferred, UIntPtr CompletionKey, IntPtr lpOverlapped);
+
+        [DllImport(Libraries.Kernel32, SetLastError = true)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static extern bool GetQueuedCompletionStatus(IntPtr CompletionPort, out int lpNumberOfBytes, out UIntPtr CompletionKey, out IntPtr lpOverlapped, int dwMilliseconds);
+    }
+}
diff --git a/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems b/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems
index 8f7d0c6951c3..7cd55aa5987c 100644
--- a/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems
+++ b/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems
@@ -1047,6 +1047,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Interop.BOOLEAN.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Interop.Libraries.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.CancelIoEx.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.CompletionPort.cs" Condition="'$(FeaturePortableThreadPool)' == 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.ExpandEnvironmentStrings.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.FileAttributes.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.FILE_INFO_BY_HANDLE_CLASS.cs" />
@@ -1075,7 +1076,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetSystemTime.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetSystemTimeAsFileTime.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetSystemTimePreciseAsFileTime.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetSystemTimes.cs" Condition="'$(FeaturePerfTracing)' == 'true'" />
+    <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetSystemTimes.cs" Condition="'$(FeaturePerfTracing)' == 'true' OR '$(FeaturePortableThreadPool)' == 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetTempFileNameW.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetTempPathW.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetVersionExW.cs" />
@@ -1366,7 +1367,6 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\PortableThreadPool.WorkerThread.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\PortableThreadPool.CpuUtilizationReader.Unix.cs" Condition="'$(TargetsUnix)' == 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\PortableThreadPool.CpuUtilizationReader.Windows.cs" Condition="'$(TargetsWindows)'=='true'" />
-    <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.GetSystemTimes.cs" Condition="'$(TargetsWindows)' == 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\LowLevelLifoSemaphore.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\LowLevelLifoSemaphore.Windows.cs" Condition="'$(TargetsWindows)'=='true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\HighPerformanceCounter.Unix.cs" Condition="'$(TargetsUnix)' == 'true'" />