diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2b0150e8f4cc0..a3a4d15c54fd2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -192,16 +192,6 @@ option(SWIFT_STDLIB_ENABLE_UNICODE_DATA
     NOTE: Disabling this will cause many String methods to crash."
     TRUE)
 
-include(Threading)
-
-threading_package_default("${SWIFT_HOST_VARIANT_SDK}"
-  SWIFT_THREADING_PACKAGE_default)
-
-set(SWIFT_THREADING_PACKAGE "${SWIFT_THREADING_PACKAGE_default}"
-    CACHE STRING
-    "The threading package to use.  Must be one of 'none', 'pthreads',
-    'darwin', 'linux', 'win32', 'c11'.")
-
 option(SWIFT_BUILD_DYNAMIC_SDK_OVERLAY
     "Build dynamic variants of the Swift SDK overlay"
     TRUE)
@@ -1054,7 +1044,6 @@ if(SWIFT_BUILD_STDLIB OR SWIFT_BUILD_SDK_OVERLAY)
   message(STATUS "  Leak Detection Checker Entrypoints: ${SWIFT_RUNTIME_ENABLE_LEAK_CHECKER}")
   message(STATUS "")
 
-  message(STATUS "Threading Package:                  ${SWIFT_THREADING_PACKAGE}")
   message(STATUS "Differentiable Programming Support: ${SWIFT_ENABLE_EXPERIMENTAL_DIFFERENTIABLE_PROGRAMMING}")
   message(STATUS "Concurrency Support:                ${SWIFT_ENABLE_EXPERIMENTAL_CONCURRENCY}")
   message(STATUS "Distributed Support:                ${SWIFT_ENABLE_EXPERIMENTAL_DISTRIBUTED}")
diff --git a/cmake/modules/Threading.cmake b/cmake/modules/Threading.cmake
index f439ed0ba90b0..979f2e1ca0d1f 100644
--- a/cmake/modules/Threading.cmake
+++ b/cmake/modules/Threading.cmake
@@ -1,5 +1,7 @@
 # Get the default threading package for the platform
 function(threading_package_default sdk out_var)
+    precondition(SWIFT_DARWIN_PLATFORMS)
+
     if(sdk IN_LIST SWIFT_DARWIN_PLATFORMS)
       set("${out_var}" "darwin" PARENT_SCOPE)
     elseif(sdk STREQUAL "LINUX")
@@ -13,16 +15,30 @@ function(threading_package_default sdk out_var)
     endif()
 endfunction()
 
+# Get the selected threading package
+function(threading_package_or_default sdk out_var)
+  if("${SWIFT_SDK_${sdk}_THREADING_PACKAGE}")
+    set(package "${SWIFT_SDK_${sdk}_THREADING_PACKAGE}")
+  else()
+    set(package "${SWIFT_THREADING_PACKAGE}")
+  endif()
+  if(package STREQUAL "")
+    threading_package_default("${sdk}" package)
+  endif()
+  set("${out_var}" "${package}" PARENT_SCOPE)
+endfunction()
+
 # Given the threading package, find the name for the preprocessor
 # define that we need to make.  Also deals with the default platform
 # setting.
 function(threading_package_name sdk out_var)
-  precondition(SWIFT_HOST_VARIANT_SDK)
-  precondition(SWIFT_DARWIN_PLATFORMS)
-
-  string(TOUPPER "${SWIFT_THREADING_PACKAGE}" package)
+  if("${SWIFT_SDK_${sdk}_THREADING_PACKAGE}")
+    string(TOUPPER "${SWIFT_SDK_${sdk}_THREADING_PACKAGE}" package)
+  else()
+    string(TOUPPER "${SWIFT_THREADING_PACKAGE}" package)
+  endif()
   if(package STREQUAL "")
-    threading_package_default(package)
+    threading_package_default("${sdk}" package)
     string(TOUPPER "${package}" package)
   endif()
   set("${out_var}" "${package}" PARENT_SCOPE)
diff --git a/stdlib/cmake/modules/StdlibOptions.cmake b/stdlib/cmake/modules/StdlibOptions.cmake
index 04e5e6c842e84..a54ad8df2af7b 100644
--- a/stdlib/cmake/modules/StdlibOptions.cmake
+++ b/stdlib/cmake/modules/StdlibOptions.cmake
@@ -191,16 +191,6 @@ else()
   set(SWIFT_CONCURRENCY_GLOBAL_EXECUTOR_default "dispatch")
 endif()
 
-include(Threading)
-
-threading_package_default("${SWIFT_HOST_VARIANT_SDK}"
-  SWIFT_THREADING_PACKAGE_default)
-
-set(SWIFT_THREADING_PACKAGE "${SWIFT_THREADING_PACKAGE_default}"
-    CACHE STRING
-    "The threading package to use.  Must be one of 'none', 'pthreads',
-    'darwin', 'linux', 'win32', 'c11'.")
-
 set(SWIFT_CONCURRENCY_GLOBAL_EXECUTOR
     "${SWIFT_CONCURRENCY_GLOBAL_EXECUTOR_default}" CACHE STRING
     "Build the concurrency library to use the given global executor (options: dispatch, singlethreaded, hooked)")
diff --git a/stdlib/cmake/modules/SwiftSource.cmake b/stdlib/cmake/modules/SwiftSource.cmake
index c5c6366bcb5ec..63136a90e8bf8 100644
--- a/stdlib/cmake/modules/SwiftSource.cmake
+++ b/stdlib/cmake/modules/SwiftSource.cmake
@@ -483,7 +483,8 @@ function(_compile_swift_files
     list(APPEND swift_flags "-Xfrontend" "-library-level"  "-Xfrontend" "api")
   endif()
 
-  if(SWIFT_THREADING_PACKAGE STREQUAL "none")
+  threading_package_or_default("${SWIFTFILE_SDK}" _threading_package)
+  if(_threading_package STREQUAL "none")
     list(APPEND swift_flags "-Xfrontend" "-assume-single-threaded")
   endif()
 
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 30883669dcc20..cbc507fbb93b6 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -398,9 +398,9 @@ foreach(SDK ${SWIFT_SDKS})
         if("${SWIFT_SDK_${SDK}_THREADING_PACKAGE}")
           list(APPEND LIT_ARGS "--param" "threading=${SWIFT_SDK_${SDK}_THREADING_PACKAGE}")
         else()
-          threading_package_default("${SDK}" SWIFT_THREADING_PACKAGE)
+          threading_package_or_default("${SDK}" _threading_package)
           list(APPEND LIT_ARGS "--param"
-            "threading=${SWIFT_THREADING_PACKAGE}")
+            "threading=${_threading_package}")
         endif()
 
         foreach(test_subset ${TEST_SUBSETS})
diff --git a/test/lit.site.cfg.in b/test/lit.site.cfg.in
index 1299d45c51534..a2218bbccba11 100644
--- a/test/lit.site.cfg.in
+++ b/test/lit.site.cfg.in
@@ -99,11 +99,6 @@ if "@SWIFT_OPTIMIZED@" == "TRUE":
 if "@SWIFT_STDLIB_SINGLE_THREADED_CONCURRENCY@" == "TRUE":
     config.available_features.add("single_threaded_concurrency")
 
-if "@SWIFT_THREADING_PACKAGE@" != "none":
-    # This is not called "threading" because we might want that later
-    config.available_features.add("thread_safe_runtime")
-    config.available_features.add("threading_@SWIFT_THREADING_PACKAGE@")
-
 if "@SWIFT_ENABLE_REFLECTION@" == "TRUE":
     config.available_features.add("reflection")