diff --git a/libc/bionic/pthread_internals.cpp b/libc/bionic/pthread_internals.cpp
index 33cddd7..7c30e6e 100644
--- a/libc/bionic/pthread_internals.cpp
+++ b/libc/bionic/pthread_internals.cpp
@@ -41,26 +41,7 @@
 pthread_internal_t* g_thread_list = NULL;
 pthread_mutex_t g_thread_list_lock = PTHREAD_MUTEX_INITIALIZER;
 
-pthread_internal_t* __create_thread_struct() {
-  void* result = mmap(NULL, sizeof(pthread_internal_t), PROT_READ | PROT_WRITE,
-                      MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
-  if (result == MAP_FAILED) {
-    __libc_format_log(ANDROID_LOG_WARN, "libc",
-                      "__create_thread_struct() failed: %s", strerror(errno));
-    return NULL;
-  }
-  return reinterpret_cast<pthread_internal_t*>(result);
-}
-
-void __free_thread_struct(pthread_internal_t* thread) {
-  int result = munmap(thread, sizeof(pthread_internal_t));
-  if (result != 0) {
-    __libc_format_log(ANDROID_LOG_WARN, "libc",
-                      "__free_thread_struct() failed: %s", strerror(errno));
-  }
-}
-
-void _pthread_internal_remove_locked(pthread_internal_t* thread) {
+void _pthread_internal_remove_locked(pthread_internal_t* thread, bool free_thread) {
   if (thread->next != NULL) {
     thread->next->prev = thread->prev;
   }
@@ -70,10 +51,11 @@
     g_thread_list = thread->next;
   }
 
-  // The main thread is not heap-allocated. See __libc_init_tls for the declaration,
-  // and __libc_init_common for the point where it's added to the thread list.
-  if ((thread->attr.flags & PTHREAD_ATTR_FLAG_MAIN_THREAD) == 0) {
-    __free_thread_struct(thread);
+  // For threads using user allocated stack (including the main thread), the pthread_internal_t
+  // can't be freed since it is on the stack.
+  if (free_thread && !(thread->attr.flags & PTHREAD_ATTR_FLAG_USER_ALLOCATED_STACK)) {
+    // Use one munmap to free the whole thread stack, including pthread_internal_t.
+    munmap(thread->attr.stack_base, thread->attr.stack_size);
   }
 }