--- old/src/hotspot/os/linux/os_linux.cpp	2019-07-01 10:42:06.649149457 -0700
+++ new/src/hotspot/os/linux/os_linux.cpp	2019-07-01 10:42:06.321144877 -0700
@@ -826,37 +826,42 @@
                        _get_minstack_func == NULL ? "failed" : "succeeded");
 }
 
+static bool tls_size_inited = false;
+static size_t tls_size = 0;
 // Returns the size of the static TLS area glibc puts on thread stacks.
 static size_t get_static_tls_area_size(const pthread_attr_t *attr) {
-  size_t tls_size = 0;
-  if (_get_minstack_func != NULL) {
-    // Obtain the pthread minstack size by calling __pthread_get_minstack.
-    size_t minstack_size = _get_minstack_func(attr);
+  if (!tls_size_inited) {
+    tls_size_inited = true;
 
-    // Remove non-TLS area size included in minstack size returned
-    // by __pthread_get_minstack() to get the static TLS size.
-    // In glibc before 2.27, minstack size includes guard_size.
-    // In glibc 2.27 and later, guard_size is automatically added
-    // to the stack size by pthread_create and is no longer included
-    // in minstack size. In both cases, the guard_size is taken into
-    // account, so there is no need to adjust the result for that.
-    //
-    // Although __pthread_get_minstack() is a private glibc function,
-    // it is expected to have a stable behavior across future glibc
-    // versions while glibc still allocats the static TLS blocks off
-    // the stack. Following is glibc 2.28 __pthread_get_minstack():
-    //
-    // size_t
-    // __pthread_get_minstack (const pthread_attr_t *attr)
-    // {
-    //   return GLRO(dl_pagesize) + __static_tls_size + PTHREAD_STACK_MIN;
-    // }
-    //
-    //
-    // The following 'minstack_size > os::vm_page_size() + PTHREAD_STACK_MIN'
-    // if check is done for precaution.
-    if (minstack_size > (size_t)os::vm_page_size() + PTHREAD_STACK_MIN) {
-      tls_size = minstack_size - os::vm_page_size() - PTHREAD_STACK_MIN;
+    if (_get_minstack_func != NULL) {
+      // Obtain the pthread minstack size by calling __pthread_get_minstack.
+      size_t minstack_size = _get_minstack_func(attr);
+
+      // Remove non-TLS area size included in minstack size returned
+      // by __pthread_get_minstack() to get the static TLS size.
+      // In glibc before 2.27, minstack size includes guard_size.
+      // In glibc 2.27 and later, guard_size is automatically added
+      // to the stack size by pthread_create and is no longer included
+      // in minstack size. In both cases, the guard_size is taken into
+      // account, so there is no need to adjust the result for that.
+      //
+      // Although __pthread_get_minstack() is a private glibc function,
+      // it is expected to have a stable behavior across future glibc
+      // versions while glibc still allocats the static TLS blocks off
+      // the stack. Following is glibc 2.28 __pthread_get_minstack():
+      //
+      // size_t
+      // __pthread_get_minstack (const pthread_attr_t *attr)
+      // {
+      //   return GLRO(dl_pagesize) + __static_tls_size + PTHREAD_STACK_MIN;
+      // }
+      //
+      //
+      // The following 'minstack_size > os::vm_page_size() + PTHREAD_STACK_MIN'
+      // if check is done for precaution.
+      if (minstack_size > (size_t)os::vm_page_size() + PTHREAD_STACK_MIN) {
+        tls_size = minstack_size - os::vm_page_size() - PTHREAD_STACK_MIN;
+      }
     }
   }