diff --git a/libc/src/threads/linux/CMakeLists.txt b/libc/src/threads/linux/CMakeLists.txt
@@ -27,14 +27,14 @@ add_header_library(
   HDRS
     CndVar.h
     Futex.h
-    Mutex.h
     Thread.h
   DEPENDS
     .thread_start_args_h
     libc.include.sys_syscall
     libc.include.threads
     libc.src.__support.CPP.atomic
     libc.src.__support.OSUtil.osutil
+    libc.src.__support.threads.thread
 )
 
 add_entrypoint_object(
@@ -74,50 +74,6 @@ add_entrypoint_object(
     libc.src.sys.mman.munmap
 )
 
-add_entrypoint_object(
-  mtx_init
-  SRCS
-    mtx_init.cpp
-  HDRS
-    ../mtx_init.h
-  DEPENDS
-    .threads_utils
-    libc.include.threads
-)
-
-add_entrypoint_object(
-  mtx_destroy
-  SRCS
-    mtx_destroy.cpp
-  HDRS
-    ../mtx_destroy.h
-  DEPENDS
-    .threads_utils
-    libc.include.threads
-)
-
-add_entrypoint_object(
-  mtx_lock
-  SRCS
-    mtx_lock.cpp
-  HDRS
-    ../mtx_lock.h
-  DEPENDS
-    .threads_utils
-    libc.include.threads
-)
-
-add_entrypoint_object(
-  mtx_unlock
-  SRCS
-    mtx_unlock.cpp
-  HDRS
-    ../mtx_unlock.h
-  DEPENDS
-    .threads_utils
-    libc.include.threads
-)
-
 add_entrypoint_object(
   cnd_init
   SRCS
@@ -149,6 +105,7 @@ add_entrypoint_object(
   DEPENDS
     .threads_utils
     libc.include.threads
+    libc.src.__support.threads.thread
 )
 
 add_entrypoint_object(

diff --git a/libc/src/threads/linux/CndVar.h b/libc/src/threads/linux/CndVar.h
@@ -9,12 +9,11 @@
 #ifndef LLVM_LIBC_SRC_THREADS_LINUX_CNDVAR_H
 #define LLVM_LIBC_SRC_THREADS_LINUX_CNDVAR_H
 
-#include "Mutex.h"
-
 #include "include/sys/syscall.h" // For syscall numbers.
 #include "include/threads.h"     // For values like thrd_success etc.
 #include "src/__support/CPP/atomic.h"
 #include "src/__support/OSUtil/syscall.h" // For syscall functions.
+#include "src/__support/threads/mutex.h"
 
 #include <linux/futex.h> // For futex operations.
 #include <stdint.h>
@@ -38,7 +37,8 @@ struct CndVar {
 
   static int init(CndVar *cv) {
     cv->waitq_front = cv->waitq_back = nullptr;
-    return Mutex::init(&cv->qmtx, mtx_plain);
+    auto err = Mutex::init(&cv->qmtx, false, false, false);
+    return err == MutexError::NONE ? thrd_success : thrd_error;
   }
 
   static void destroy(CndVar *cv) {
@@ -67,7 +67,7 @@ struct CndVar {
         waitq_back = &waiter;
       }
 
-      if (m->unlock() != thrd_success) {
+      if (m->unlock() != MutexError::NONE) {
         // If we do not remove the queued up waiter before returning,
         // then another thread can potentially signal a non-existing
         // waiter. Note also that we do this with |qmtx| locked. This
@@ -88,7 +88,8 @@ struct CndVar {
 
     // At this point, if locking |m| fails, we can simply return as the
     // queued up waiter would have been removed from the queue.
-    return m->lock();
+    auto err = m->lock();
+    return err == MutexError::NONE ? thrd_success : thrd_error;
   }
 
   int notify_one() {
@@ -105,7 +106,7 @@ struct CndVar {
     if (waitq_front == nullptr)
       waitq_back = nullptr;
 
-    qmtx.futex_word = Mutex::MS_Free;
+    qmtx.futex_word = Mutex::FutexWordType(Mutex::LockState::Free);
 
     __llvm_libc::syscall(
         SYS_futex, &qmtx.futex_word.val, FUTEX_WAKE_OP, 1, 1,

diff --git a/libc/src/threads/linux/Mutex.h b/libc/src/threads/linux/Mutex.h
diff --git a/libc/src/threads/linux/cnd_wait.cpp b/libc/src/threads/linux/cnd_wait.cpp
@@ -7,10 +7,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "CndVar.h"
-#include "Mutex.h"
 
-#include "src/threads/cnd_wait.h"
 #include "src/__support/common.h"
+#include "src/__support/threads/mutex.h"
+#include "src/threads/cnd_wait.h"
 
 namespace __llvm_libc {
 

diff --git a/libc/src/threads/linux/mtx_destroy.cpp → libc/src/threads/mtx_destroy.cpp b/libc/src/threads/linux/mtx_destroy.cpp → libc/src/threads/mtx_destroy.cpp
@@ -9,7 +9,7 @@
 #include "src/threads/mtx_destroy.h"
 #include "include/threads.h" // For mtx_t definition.
 #include "src/__support/common.h"
-#include "src/threads/linux/Mutex.h"
+#include "src/__support/threads/mutex.h"
 
 namespace __llvm_libc {
 

diff --git a/libc/src/threads/linux/mtx_init.cpp → libc/src/threads/mtx_init.cpp b/libc/src/threads/linux/mtx_init.cpp → libc/src/threads/mtx_init.cpp
@@ -9,13 +9,13 @@
 #include "src/threads/mtx_init.h"
 #include "include/threads.h" // For mtx_t definition.
 #include "src/__support/common.h"
-#include "src/threads/linux/Mutex.h"
+#include "src/__support/threads/mutex.h"
 
 namespace __llvm_libc {
 
-LLVM_LIBC_FUNCTION(int, mtx_init, (mtx_t * mutex, int type)) {
-  auto *m = reinterpret_cast<Mutex *>(mutex);
-  return Mutex::init(m, type);
+LLVM_LIBC_FUNCTION(int, mtx_init, (mtx_t * m, int type)) {
+  auto err = Mutex::init(m, type | mtx_timed, type | mtx_recursive, 0);
+  return err == MutexError::NONE ? thrd_success : thrd_error;
 }
 
 } // namespace __llvm_libc
diff --git a/libc/src/threads/linux/mtx_lock.cpp → libc/src/threads/mtx_lock.cpp b/libc/src/threads/linux/mtx_lock.cpp → libc/src/threads/mtx_lock.cpp
@@ -7,16 +7,17 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/threads/mtx_lock.h"
-#include "include/threads.h"      // For mtx_t definition.
+#include "include/threads.h" // For mtx_t definition.
 #include "src/__support/common.h"
-#include "src/threads/linux/Mutex.h"
+#include "src/__support/threads/mutex.h"
 
 namespace __llvm_libc {
 
 // The implementation currently handles only plain mutexes.
 LLVM_LIBC_FUNCTION(int, mtx_lock, (mtx_t * mutex)) {
   auto *m = reinterpret_cast<Mutex *>(mutex);
-  return m->lock();
+  auto err = m->lock();
+  return err == MutexError::NONE ? thrd_success : thrd_error;
 }
 
 } // namespace __llvm_libc
diff --git a/libc/src/threads/linux/mtx_unlock.cpp → libc/src/threads/mtx_unlock.cpp b/libc/src/threads/linux/mtx_unlock.cpp → libc/src/threads/mtx_unlock.cpp
@@ -7,16 +7,17 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/threads/mtx_unlock.h"
-#include "include/threads.h"      // For mtx_t definition.
+#include "include/threads.h" // For mtx_t definition.
 #include "src/__support/common.h"
-#include "src/threads/linux/Mutex.h"
+#include "src/__support/threads/mutex.h"
 
 namespace __llvm_libc {
 
 // The implementation currently handles only plain mutexes.
 LLVM_LIBC_FUNCTION(int, mtx_unlock, (mtx_t * mutex)) {
   auto *m = reinterpret_cast<Mutex *>(mutex);
-  return m->unlock();
+  auto err = m->unlock();
+  return err == MutexError::NONE ? thrd_success : thrd_error;
 }
 
 } // namespace __llvm_libc