diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
index e42c16b31fcb..fcd883743eba 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
@@ -8,8 +8,6 @@
 //
 // UNSUPPORTED: libcpp-has-no-threads
 
-// ALLOW_RETRIES: 2
-
 // <mutex>
 
 // template <class Mutex> class lock_guard;
@@ -17,7 +15,6 @@
 // lock_guard(mutex_type& m, adopt_lock_t);
 
 #include <mutex>
-#include <thread>
 #include <cstdlib>
 #include <cassert>
 
@@ -25,32 +22,16 @@
 
 std::mutex m;
 
-typedef std::chrono::system_clock Clock;
-typedef Clock::time_point time_point;
-typedef Clock::duration duration;
-typedef std::chrono::milliseconds ms;
-typedef std::chrono::nanoseconds ns;
-
-void f()
+int main()
 {
-    time_point t0 = Clock::now();
-    time_point t1;
-    {
+  {
     m.lock();
     std::lock_guard<std::mutex> lg(m, std::adopt_lock);
-    t1 = Clock::now();
-    }
-    ns d = t1 - t0 - ms(250);
-    assert(d < ms(50));  // within 50ms
-}
+    assert(m.try_lock() == false);
+  }
 
-int main(int, char**)
-{
-    m.lock();
-    std::thread t(f);
-    std::this_thread::sleep_for(ms(250));
-    m.unlock();
-    t.join();
+  m.lock();
+  m.unlock();
 
   return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
index fc2230591aea..71a72ffd050e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
@@ -8,8 +8,6 @@
 //
 // UNSUPPORTED: libcpp-has-no-threads
 
-// ALLOW_RETRIES: 2
-
 // <mutex>
 
 // template <class Mutex> class lock_guard;
@@ -20,7 +18,6 @@
 //     -> lock_guard<_Mutex>;  // C++17
 
 #include <mutex>
-#include <thread>
 #include <cstdlib>
 #include <cassert>
 
@@ -28,35 +25,19 @@
 
 std::mutex m;
 
-typedef std::chrono::system_clock Clock;
-typedef Clock::time_point time_point;
-typedef Clock::duration duration;
-typedef std::chrono::milliseconds ms;
-typedef std::chrono::nanoseconds ns;
-
-void f()
+int main()
 {
-    time_point t0 = Clock::now();
-    time_point t1;
-    {
+  {
     std::lock_guard<std::mutex> lg(m);
-    t1 = Clock::now();
-    }
-    ns d = t1 - t0 - ms(250);
-    assert(d < ms(200));  // within 200ms
-}
+    assert(m.try_lock() == false);
+  }
 
-int main(int, char**)
-{
-    m.lock();
-    std::thread t(f);
-    std::this_thread::sleep_for(ms(250));
-    m.unlock();
-    t.join();
+  m.lock();
+  m.unlock();
 
 #ifdef __cpp_deduction_guides
-    std::lock_guard lg(m);
-    static_assert((std::is_same<decltype(lg), std::lock_guard<decltype(m)>>::value), "" );
+  std::lock_guard lg(m);
+  static_assert((std::is_same<decltype(lg), std::lock_guard<decltype(m)>>::value), "" );
 #endif
 
   return 0;