src/os/linux/vm/os_linux.cpp

rev 4531 : 8013398: Adjust number of stack guard pages on systems with large memory page size
Summary: Auto adjust number of stack guard pages on systems with large memory page size
Reviewed-by: bobv, coleenp

@@ -136,10 +136,11 @@
 int (*os::Linux::_clock_gettime)(clockid_t, struct timespec *) = NULL;
 int (*os::Linux::_pthread_getcpuclockid)(pthread_t, clockid_t *) = NULL;
 Mutex* os::Linux::_createThread_lock = NULL;
 pthread_t os::Linux::_main_thread;
 int os::Linux::_page_size = -1;
+const int os::Linux::_vm_default_page_size = (8 * K);
 bool os::Linux::_is_floating_stack = false;
 bool os::Linux::_is_NPTL = false;
 bool os::Linux::_supports_fast_thread_cpu_time = false;
 const char * os::Linux::_glibc_version = NULL;
 const char * os::Linux::_libpthread_version = NULL;

@@ -4383,10 +4384,19 @@
   Linux::_main_thread = pthread_self();
 
   Linux::clock_init();
   initial_time_count = os::elapsed_counter();
   pthread_mutex_init(&dl_mutex, NULL);
+
+  // If the pagesize of the VM is greater than 8K determine the appropriate
+  // number of initial guard pages.  The user can change this with the
+  // command line arguments, if needed.
+  if (vm_page_size() > (int)Linux::vm_default_page_size()) {
+    StackYellowPages = 1;
+    StackRedPages = 1;
+    StackShadowPages = round_to((StackShadowPages*Linux::vm_default_page_size()), vm_page_size()) / vm_page_size();
+  }
 }
 
 // To install functions for atexit system call
 extern "C" {
   static void perfMemory_exit_helper() {

@@ -4436,12 +4446,12 @@
   // the java system classes, including StackOverflowError - depends on page
   // size.  Add a page for compiler2 recursion in main thread.
   // Add in 2*BytesPerWord times page size to account for VM stack during
   // class initialization depending on 32 or 64 bit VM.
   os::Linux::min_stack_allowed = MAX2(os::Linux::min_stack_allowed,
-            (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
-                    2*BytesPerWord COMPILER2_PRESENT(+1)) * Linux::page_size());
+            (size_t)(StackYellowPages+StackRedPages+StackShadowPages) * Linux::page_size() +
+                    (2*BytesPerWord COMPILER2_PRESENT(+1)) * Linux::vm_default_page_size());
 
   size_t threadStackSizeInBytes = ThreadStackSize * K;
   if (threadStackSizeInBytes != 0 &&
       threadStackSizeInBytes < os::Linux::min_stack_allowed) {
         tty->print_cr("\nThe stack size specified is too small, "