diff --git a/libc/bionic/pthread_internal.h b/libc/bionic/pthread_internal.h
index 8da99dd..99882ae 100644
--- a/libc/bionic/pthread_internal.h
+++ b/libc/bionic/pthread_internal.h
@@ -113,8 +113,10 @@
 __LIBC_HIDDEN__ void __init_alternate_signal_stack(pthread_internal_t*);
 __LIBC_HIDDEN__ void _pthread_internal_add(pthread_internal_t* thread);
 
-/* Various third-party apps contain a backport of our pthread_rwlock implementation that uses this. */
-extern "C" __LIBC64_HIDDEN__ pthread_internal_t* __get_thread(void);
+// Make __get_thread() inlined for performance reason. See http://b/19825434.
+static inline __always_inline pthread_internal_t* __get_thread() {
+  return reinterpret_cast<pthread_internal_t*>(__get_tls()[TLS_SLOT_THREAD_ID]);
+}
 
 __LIBC_HIDDEN__ void pthread_key_clean_all(void);
 __LIBC_HIDDEN__ void _pthread_internal_remove_locked(pthread_internal_t* thread, bool free_thread);