8169373: Work around linux NPTL stack guard error.
authorgoetz
Tue, 08 Nov 2016 16:30:36 +0100
changeset 42905 1af223983f82
parent 42658 9b8b24e4fc01
child 42906 1a8db9cf1407
8169373: Work around linux NPTL stack guard error. Summary: Also skip libc guard page for compiler thread, merge similar code on linux platforms, and streamline libc guard page handling on linuxs390, linuxppc, aixppc. Reviewed-by: dholmes, dcubed, kvn
hotspot/src/os/aix/vm/os_aix.cpp
hotspot/src/os/aix/vm/os_aix.hpp
hotspot/src/os/linux/vm/os_linux.cpp
hotspot/src/os/posix/vm/os_posix.cpp
hotspot/src/os_cpu/aix_ppc/vm/os_aix_ppc.cpp
hotspot/src/os_cpu/bsd_x86/vm/os_bsd_x86.cpp
hotspot/src/os_cpu/bsd_zero/vm/os_bsd_zero.cpp
hotspot/src/os_cpu/linux_aarch64/vm/os_linux_aarch64.cpp
hotspot/src/os_cpu/linux_ppc/vm/os_linux_ppc.cpp
hotspot/src/os_cpu/linux_s390/vm/os_linux_s390.cpp
hotspot/src/os_cpu/linux_sparc/vm/os_linux_sparc.cpp
hotspot/src/os_cpu/linux_x86/vm/os_linux_x86.cpp
hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp
--- a/hotspot/src/os/aix/vm/os_aix.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os/aix/vm/os_aix.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -848,13 +848,13 @@
 
   assert(thread->osthread() == NULL, "caller responsible");
 
-  // Allocate the OSThread object
+  // Allocate the OSThread object.
   OSThread* osthread = new OSThread(NULL, NULL);
   if (osthread == NULL) {
     return false;
   }
 
-  // set the correct thread state
+  // Set the correct thread state.
   osthread->set_thread_type(thr_type);
 
   // Initial state is ALLOCATED but not INITIALIZED
@@ -862,7 +862,7 @@
 
   thread->set_osthread(osthread);
 
-  // init thread attributes
+  // Init thread attributes.
   pthread_attr_t attr;
   pthread_attr_init(&attr);
   guarantee(pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) == 0, "???");
@@ -871,15 +871,18 @@
   if (os::Aix::on_aix()) {
     guarantee(pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM) == 0, "???");
     guarantee(pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED) == 0, "???");
-  } // end: aix
+  }
 
   // Start in suspended state, and in os::thread_start, wake the thread up.
   guarantee(pthread_attr_setsuspendstate_np(&attr, PTHREAD_CREATE_SUSPENDED_NP) == 0, "???");
 
-  // calculate stack size if it's not specified by caller
+  // Calculate stack size if it's not specified by caller.
   size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
   pthread_attr_setstacksize(&attr, stack_size);
 
+  // Configure libc guard page.
+  pthread_attr_setguardsize(&attr, os::Aix::default_guard_size(thr_type));
+
   pthread_t tid;
   int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
 
@@ -895,7 +898,7 @@
   pthread_attr_destroy(&attr);
 
   if (ret != 0) {
-    // Need to clean up stuff we've allocated so far
+    // Need to clean up stuff we've allocated so far.
     thread->set_osthread(NULL);
     delete osthread;
     return false;
@@ -3032,6 +3035,19 @@
   return chained;
 }
 
+size_t os::Aix::default_guard_size(os::ThreadType thr_type) {
+  // Creating guard page is very expensive. Java thread has HotSpot
+  // guard pages, only enable glibc guard page for non-Java threads.
+  // (Remember: compiler thread is a Java thread, too!)
+  //
+  // Aix can have different page sizes for stack (4K) and heap (64K).
+  // As Hotspot knows only one page size, we assume the stack has
+  // the same page size as the heap. Returning page_size() here can
+  // cause 16 guard pages which we want to avoid.  Thus we return 4K
+  // which will be rounded to the real page size by the OS.
+  return ((thr_type == java_thread || thr_type == compiler_thread) ? 0 : 4 * K);
+}
+
 struct sigaction* os::Aix::get_preinstalled_handler(int sig) {
   if (sigismember(&sigs, sig)) {
     return &sigact[sig];
--- a/hotspot/src/os/aix/vm/os_aix.hpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os/aix/vm/os_aix.hpp	Tue Nov 08 16:30:36 2016 +0100
@@ -140,6 +140,9 @@
   // libpthread version string
   static void libpthread_init();
 
+  // Return default libc guard size for the specified thread type.
+  static size_t default_guard_size(os::ThreadType thr_type);
+
   // Function returns true if we run on OS/400 (pase), false if we run
   // on AIX.
   static bool on_pase() {
--- a/hotspot/src/os/linux/vm/os_linux.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os/linux/vm/os_linux.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -716,11 +716,18 @@
   pthread_attr_init(&attr);
   pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
 
-  // calculate stack size if it's not specified by caller
+  // Calculate stack size if it's not specified by caller.
   size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
+  // In the Linux NPTL pthread implementation the guard size mechanism
+  // is not implemented properly. The posix standard requires adding
+  // the size of the guard pages to the stack size, instead Linux
+  // takes the space out of 'stacksize'. Thus we adapt the requested
+  // stack_size by the size of the guard pages to mimick proper
+  // behaviour.
+  stack_size = align_size_up(stack_size + os::Linux::default_guard_size(thr_type), vm_page_size());
   pthread_attr_setstacksize(&attr, stack_size);
 
-  // glibc guard page
+  // Configure glibc guard page.
   pthread_attr_setguardsize(&attr, os::Linux::default_guard_size(thr_type));
 
   ThreadState state;
@@ -2833,6 +2840,13 @@
   return false;
 }
 
+size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
+  // Creating guard page is very expensive. Java thread has HotSpot
+  // guard pages, only enable glibc guard page for non-Java threads.
+  // (Remember: compiler thread is a Java thread, too!)
+  return ((thr_type == java_thread || thr_type == compiler_thread) ? 0 : page_size());
+}
+
 // rebuild_cpu_to_node_map() constructs a table mapping cpud id to node id.
 // The table is later used in get_node_by_cpu().
 void os::Linux::rebuild_cpu_to_node_map() {
@@ -6065,6 +6079,101 @@
   return yes;
 }
 
+
+// Java/Compiler thread:
+//
+//   Low memory addresses
+// P0 +------------------------+
+//    |                        |\  Java thread created by VM does not have glibc
+//    |    glibc guard page    | - guard page, attached Java thread usually has
+//    |                        |/  1 glibc guard page.
+// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
+//    |                        |\
+//    |  HotSpot Guard Pages   | - red, yellow and reserved pages
+//    |                        |/
+//    +------------------------+ JavaThread::stack_reserved_zone_base()
+//    |                        |\
+//    |      Normal Stack      | -
+//    |                        |/
+// P2 +------------------------+ Thread::stack_base()
+//
+// Non-Java thread:
+//
+//   Low memory addresses
+// P0 +------------------------+
+//    |                        |\
+//    |  glibc guard page      | - usually 1 page
+//    |                        |/
+// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
+//    |                        |\
+//    |      Normal Stack      | -
+//    |                        |/
+// P2 +------------------------+ Thread::stack_base()
+//
+// ** P1 (aka bottom) and size (P2 = P1 - size) are the address and stack size
+//    returned from pthread_attr_getstack().
+// ** Due to NPTL implementation error, linux takes the glibc guard page out
+//    of the stack size given in pthread_attr. We work around this for
+//    threads created by the VM. (We adapt bottom to be P1 and size accordingly.)
+//
+#ifndef ZERO
+static void current_stack_region(address * bottom, size_t * size) {
+  if (os::Linux::is_initial_thread()) {
+    // initial thread needs special handling because pthread_getattr_np()
+    // may return bogus value.
+    *bottom = os::Linux::initial_thread_stack_bottom();
+    *size   = os::Linux::initial_thread_stack_size();
+  } else {
+    pthread_attr_t attr;
+
+    int rslt = pthread_getattr_np(pthread_self(), &attr);
+
+    // JVM needs to know exact stack location, abort if it fails
+    if (rslt != 0) {
+      if (rslt == ENOMEM) {
+        vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
+      } else {
+        fatal("pthread_getattr_np failed with error = %d", rslt);
+      }
+    }
+
+    if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
+      fatal("Cannot locate current stack attributes!");
+    }
+
+    // Work around NPTL stack guard error.
+    size_t guard_size = 0;
+    rslt = pthread_attr_getguardsize(&attr, &guard_size);
+    if (rslt != 0) {
+      fatal("pthread_attr_getguardsize failed with error = %d", rslt);
+    }
+    *bottom += guard_size;
+    *size   -= guard_size;
+
+    pthread_attr_destroy(&attr);
+
+  }
+  assert(os::current_stack_pointer() >= *bottom &&
+         os::current_stack_pointer() < *bottom + *size, "just checking");
+}
+
+address os::current_stack_base() {
+  address bottom;
+  size_t size;
+  current_stack_region(&bottom, &size);
+  return (bottom + size);
+}
+
+size_t os::current_stack_size() {
+  // This stack size includes the usable stack and HotSpot guard pages
+  // (for the threads that have Hotspot guard pages).
+  address bottom;
+  size_t size;
+  current_stack_region(&bottom, &size);
+  return size;
+}
+#endif
+
 static inline struct timespec get_mtime(const char* filename) {
   struct stat st;
   int ret = os::stat(filename, &st);
--- a/hotspot/src/os/posix/vm/os_posix.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os/posix/vm/os_posix.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -1096,6 +1096,8 @@
   int detachstate = 0;
   pthread_attr_getstacksize(attr, &stack_size);
   pthread_attr_getguardsize(attr, &guard_size);
+  // Work around linux NPTL implementation error, see also os::create_thread() in os_linux.cpp.
+  LINUX_ONLY(stack_size -= guard_size);
   pthread_attr_getdetachstate(attr, &detachstate);
   jio_snprintf(buf, buflen, "stacksize: " SIZE_FORMAT "k, guardsize: " SIZE_FORMAT "k, %s",
     stack_size / 1024, guard_size / 1024,
--- a/hotspot/src/os_cpu/aix_ppc/vm/os_aix_ppc.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/aix_ppc/vm/os_aix_ppc.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -535,13 +535,15 @@
 ////////////////////////////////////////////////////////////////////////////////
 // thread stack
 
-size_t os::Posix::_compiler_thread_min_stack_allowed = 128 * K;
-size_t os::Posix::_java_thread_min_stack_allowed = 128 * K;
+// These sizes exclude libc stack guard pages, but include
+// the HotSpot guard pages.
+size_t os::Posix::_compiler_thread_min_stack_allowed = 512 * K;
+size_t os::Posix::_java_thread_min_stack_allowed = 512 * K;
 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 128 * K;
 
-// return default stack size for thr_type
+// Return default stack size for thr_type.
 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
-  // default stack size (compiler thread needs larger stack)
+  // Default stack size (compiler thread needs larger stack).
   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
   return s;
 }
--- a/hotspot/src/os_cpu/bsd_x86/vm/os_bsd_x86.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/bsd_x86/vm/os_bsd_x86.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -870,14 +870,14 @@
 //
 //   Low memory addresses
 //    +------------------------+
-//    |                        |\  JavaThread created by VM does not have glibc
+//    |                        |\  Java thread created by VM does not have glibc
 //    |    glibc guard page    | - guard, attached Java thread usually has
-//    |                        |/  1 page glibc guard.
+//    |                        |/  1 glibc guard page.
 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
 //    |                        |\
-//    |  HotSpot Guard Pages   | - red and yellow pages
+//    |  HotSpot Guard Pages   | - red, yellow and reserved pages
 //    |                        |/
-//    +------------------------+ JavaThread::stack_yellow_zone_base()
+//    +------------------------+ JavaThread::stack_reserved_zone_base()
 //    |                        |\
 //    |      Normal Stack      | -
 //    |                        |/
@@ -925,7 +925,7 @@
   int rslt = pthread_stackseg_np(pthread_self(), &ss);
 
   if (rslt != 0)
-    fatal("pthread_stackseg_np failed with err = %d", rslt);
+    fatal("pthread_stackseg_np failed with error = %d", rslt);
 
   *bottom = (address)((char *)ss.ss_sp - ss.ss_size);
   *size   = ss.ss_size;
@@ -936,12 +936,12 @@
 
   // JVM needs to know exact stack location, abort if it fails
   if (rslt != 0)
-    fatal("pthread_attr_init failed with err = %d", rslt);
+    fatal("pthread_attr_init failed with error = %d", rslt);
 
   rslt = pthread_attr_get_np(pthread_self(), &attr);
 
   if (rslt != 0)
-    fatal("pthread_attr_get_np failed with err = %d", rslt);
+    fatal("pthread_attr_get_np failed with error = %d", rslt);
 
   if (pthread_attr_getstackaddr(&attr, (void **)bottom) != 0 ||
     pthread_attr_getstacksize(&attr, size) != 0) {
--- a/hotspot/src/os_cpu/bsd_zero/vm/os_bsd_zero.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/bsd_zero/vm/os_bsd_zero.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -310,7 +310,7 @@
   int rslt = pthread_stackseg_np(pthread_self(), &ss);
 
   if (rslt != 0)
-    fatal("pthread_stackseg_np failed with err = " INT32_FORMAT, rslt);
+    fatal("pthread_stackseg_np failed with error = " INT32_FORMAT, rslt);
 
   stack_top = (address) ss.ss_sp;
   stack_bytes  = ss.ss_size;
@@ -322,12 +322,12 @@
 
   // JVM needs to know exact stack location, abort if it fails
   if (rslt != 0)
-    fatal("pthread_attr_init failed with err = " INT32_FORMAT, rslt);
+    fatal("pthread_attr_init failed with error = " INT32_FORMAT, rslt);
 
   rslt = pthread_attr_get_np(pthread_self(), &attr);
 
   if (rslt != 0)
-    fatal("pthread_attr_get_np failed with err = " INT32_FORMAT, rslt);
+    fatal("pthread_attr_get_np failed with error = " INT32_FORMAT, rslt);
 
   if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||
       pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {
--- a/hotspot/src/os_cpu/linux_aarch64/vm/os_linux_aarch64.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/linux_aarch64/vm/os_linux_aarch64.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -484,91 +484,6 @@
   return s;
 }
 
-size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
-  // Creating guard page is very expensive. Java thread has HotSpot
-  // guard page, only enable glibc guard page for non-Java threads.
-  return (thr_type == java_thread ? 0 : page_size());
-}
-
-// Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\  JavaThread created by VM does not have glibc
-//    |    glibc guard page    | - guard, attached Java thread usually has
-//    |                        |/  1 page glibc guard.
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |  HotSpot Guard Pages   | - red and yellow pages
-//    |                        |/
-//    +------------------------+ JavaThread::stack_yellow_zone_base()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// Non-Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\
-//    |  glibc guard page      | - usually 1 page
-//    |                        |/
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
-//    pthread_attr_getstack()
-
-static void current_stack_region(address * bottom, size_t * size) {
-  if (os::Linux::is_initial_thread()) {
-     // initial thread needs special handling because pthread_getattr_np()
-     // may return bogus value.
-     *bottom = os::Linux::initial_thread_stack_bottom();
-     *size   = os::Linux::initial_thread_stack_size();
-  } else {
-     pthread_attr_t attr;
-
-     int rslt = pthread_getattr_np(pthread_self(), &attr);
-
-     // JVM needs to know exact stack location, abort if it fails
-     if (rslt != 0) {
-       if (rslt == ENOMEM) {
-         vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
-       } else {
-         fatal("pthread_getattr_np failed with errno = %d", rslt);
-       }
-     }
-
-     if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
-         fatal("Can not locate current stack attributes!");
-     }
-
-     pthread_attr_destroy(&attr);
-
-  }
-  assert(os::current_stack_pointer() >= *bottom &&
-         os::current_stack_pointer() < *bottom + *size, "just checking");
-}
-
-address os::current_stack_base() {
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return (bottom + size);
-}
-
-size_t os::current_stack_size() {
-  // stack size includes normal stack and HotSpot guard pages
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return size;
-}
-
 /////////////////////////////////////////////////////////////////////////////
 // helper functions for fatal error handler
 
--- a/hotspot/src/os_cpu/linux_ppc/vm/os_linux_ppc.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/linux_ppc/vm/os_linux_ppc.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -535,8 +535,10 @@
 ////////////////////////////////////////////////////////////////////////////////
 // thread stack
 
-size_t os::Posix::_compiler_thread_min_stack_allowed = 128 * K;
-size_t os::Posix::_java_thread_min_stack_allowed = 128 * K;
+// These sizes exclude libc stack guard pages, but include
+// the HotSpot guard pages.
+size_t os::Posix::_compiler_thread_min_stack_allowed = 384 * K;
+size_t os::Posix::_java_thread_min_stack_allowed = 384 * K;
 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 128 * K;
 
 // return default stack size for thr_type
@@ -546,89 +548,6 @@
   return s;
 }
 
-size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
-  return 2 * page_size();
-}
-
-// Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\  JavaThread created by VM does not have glibc
-//    |    glibc guard page    | - guard, attached Java thread usually has
-//    |                        |/  1 page glibc guard.
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |  HotSpot Guard Pages   | - red and yellow pages
-//    |                        |/
-//    +------------------------+ JavaThread::stack_yellow_zone_base()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// Non-Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\
-//    |  glibc guard page      | - usually 1 page
-//    |                        |/
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
-//    pthread_attr_getstack()
-
-static void current_stack_region(address * bottom, size_t * size) {
-  if (os::Linux::is_initial_thread()) {
-     // initial thread needs special handling because pthread_getattr_np()
-     // may return bogus value.
-    *bottom = os::Linux::initial_thread_stack_bottom();
-    *size   = os::Linux::initial_thread_stack_size();
-  } else {
-    pthread_attr_t attr;
-
-    int rslt = pthread_getattr_np(pthread_self(), &attr);
-
-    // JVM needs to know exact stack location, abort if it fails
-    if (rslt != 0) {
-      if (rslt == ENOMEM) {
-        vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
-      } else {
-        fatal("pthread_getattr_np failed with errno = %d", rslt);
-      }
-    }
-
-    if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
-      fatal("Can not locate current stack attributes!");
-    }
-
-    pthread_attr_destroy(&attr);
-
-  }
-  assert(os::current_stack_pointer() >= *bottom &&
-         os::current_stack_pointer() < *bottom + *size, "just checking");
-}
-
-address os::current_stack_base() {
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return (bottom + size);
-}
-
-size_t os::current_stack_size() {
-  // stack size includes normal stack and HotSpot guard pages
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return size;
-}
-
 /////////////////////////////////////////////////////////////////////////////
 // helper functions for fatal error handler
 
--- a/hotspot/src/os_cpu/linux_s390/vm/os_linux_s390.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/linux_s390/vm/os_linux_s390.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -473,103 +473,19 @@
 ////////////////////////////////////////////////////////////////////////////////
 // thread stack
 
+// These sizes exclude libc stack guard pages, but include
+// the HotSpot guard pages.
 size_t os::Posix::_compiler_thread_min_stack_allowed = 128 * K;
-size_t os::Posix::_java_thread_min_stack_allowed = 128 * K;
+size_t os::Posix::_java_thread_min_stack_allowed = 236 * K;
 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 128 * K;
 
-// return default stack size for thr_type
+// Return default stack size for thr_type.
 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
-  // default stack size (compiler thread needs larger stack)
+  // Default stack size (compiler thread needs larger stack).
   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K);
   return s;
 }
 
-size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
-  // z/Architecture: put 2 guard pages right in the middle of thread stack. This value
-  // should be consistent with the value used by register stack handling code.
-  return 2 * page_size();
-}
-
-// Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\
-//    |    glibc guard page    | - Right in the middle of stack, 2 pages
-//    |                        |/
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |  HotSpot Guard Pages   | - red and yellow pages
-//    |                        |/
-//    +------------------------+ JavaThread::stack_yellow_zone_base()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// Non-Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\
-//    |    glibc guard page    | - Right in the middle of stack, 2 pages
-//    |                        |/
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// ** P2 is the address returned from pthread_attr_getstackaddr(), P2 - P1
-//    is the stack size returned by pthread_attr_getstacksize().
-
-
-static void current_stack_region(address * bottom, size_t * size) {
-  if (os::Linux::is_initial_thread()) {
-    // Initial thread needs special handling because pthread_getattr_np()
-    // may return bogus value.
-    *bottom = os::Linux::initial_thread_stack_bottom();
-    *size   = os::Linux::initial_thread_stack_size();
-  } else {
-    pthread_attr_t attr;
-
-    int rslt = pthread_getattr_np(pthread_self(), &attr);
-
-    // JVM needs to know exact stack location, abort if it fails
-    if (rslt != 0) {
-      if (rslt == ENOMEM) {
-        vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
-      } else {
-        fatal("pthread_getattr_np failed with errno = %d", rslt);
-      }
-    }
-
-    if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
-      fatal("Can not locate current stack attributes!");
-    }
-
-    pthread_attr_destroy(&attr);
-
-  }
-  assert(os::current_stack_pointer() >= *bottom &&
-         os::current_stack_pointer() < *bottom + *size, "just checking");
-}
-
-address os::current_stack_base() {
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return (bottom + size);
-}
-
-size_t os::current_stack_size() {
-  // stack size includes normal stack and HotSpot guard pages
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return size;
-}
-
 /////////////////////////////////////////////////////////////////////////////
 // helper functions for fatal error handler
 
--- a/hotspot/src/os_cpu/linux_sparc/vm/os_linux_sparc.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/linux_sparc/vm/os_linux_sparc.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -156,51 +156,6 @@
   return (address)sp;
 }
 
-static void current_stack_region(address* bottom, size_t* size) {
-  if (os::Linux::is_initial_thread()) {
-    // initial thread needs special handling because pthread_getattr_np()
-    // may return bogus value.
-    *bottom = os::Linux::initial_thread_stack_bottom();
-    *size = os::Linux::initial_thread_stack_size();
-  } else {
-    pthread_attr_t attr;
-
-    int rslt = pthread_getattr_np(pthread_self(), &attr);
-
-    // JVM needs to know exact stack location, abort if it fails
-    if (rslt != 0) {
-      if (rslt == ENOMEM) {
-        vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
-      } else {
-        fatal("pthread_getattr_np failed with errno = %d", rslt);
-      }
-    }
-
-    if (pthread_attr_getstack(&attr, (void**)bottom, size) != 0) {
-      fatal("Can not locate current stack attributes!");
-    }
-
-    pthread_attr_destroy(&attr);
-  }
-  assert(os::current_stack_pointer() >= *bottom &&
-         os::current_stack_pointer() < *bottom + *size, "just checking");
-}
-
-address os::current_stack_base() {
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return bottom + size;
-}
-
-size_t os::current_stack_size() {
-  // stack size includes normal stack and HotSpot guard pages
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return size;
-}
-
 char* os::non_memory_address_word() {
   // Must never look like an address returned by reserve_memory,
   // even in its subfields (as defined by the CPU immediate fields,
@@ -737,12 +692,6 @@
   return s;
 }
 
-size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
-  // Creating guard page is very expensive. Java thread has HotSpot
-  // guard page, only enable glibc guard page for non-Java threads.
-  return (thr_type == java_thread ? 0 : page_size());
-}
-
 #ifndef PRODUCT
 void os::verify_stack_alignment() {
 }
--- a/hotspot/src/os_cpu/linux_x86/vm/os_linux_x86.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/linux_x86/vm/os_linux_x86.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -698,91 +698,6 @@
   return s;
 }
 
-size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
-  // Creating guard page is very expensive. Java thread has HotSpot
-  // guard page, only enable glibc guard page for non-Java threads.
-  return (thr_type == java_thread ? 0 : page_size());
-}
-
-// Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\  JavaThread created by VM does not have glibc
-//    |    glibc guard page    | - guard, attached Java thread usually has
-//    |                        |/  1 page glibc guard.
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |  HotSpot Guard Pages   | - red and yellow pages
-//    |                        |/
-//    +------------------------+ JavaThread::stack_yellow_zone_base()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// Non-Java thread:
-//
-//   Low memory addresses
-//    +------------------------+
-//    |                        |\
-//    |  glibc guard page      | - usually 1 page
-//    |                        |/
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-//    |                        |\
-//    |      Normal Stack      | -
-//    |                        |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
-//    pthread_attr_getstack()
-
-static void current_stack_region(address * bottom, size_t * size) {
-  if (os::Linux::is_initial_thread()) {
-     // initial thread needs special handling because pthread_getattr_np()
-     // may return bogus value.
-     *bottom = os::Linux::initial_thread_stack_bottom();
-     *size   = os::Linux::initial_thread_stack_size();
-  } else {
-     pthread_attr_t attr;
-
-     int rslt = pthread_getattr_np(pthread_self(), &attr);
-
-     // JVM needs to know exact stack location, abort if it fails
-     if (rslt != 0) {
-       if (rslt == ENOMEM) {
-         vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
-       } else {
-         fatal("pthread_getattr_np failed with errno = %d", rslt);
-       }
-     }
-
-     if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
-         fatal("Can not locate current stack attributes!");
-     }
-
-     pthread_attr_destroy(&attr);
-
-  }
-  assert(os::current_stack_pointer() >= *bottom &&
-         os::current_stack_pointer() < *bottom + *size, "just checking");
-}
-
-address os::current_stack_base() {
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return (bottom + size);
-}
-
-size_t os::current_stack_size() {
-  // stack size includes normal stack and HotSpot guard pages
-  address bottom;
-  size_t size;
-  current_stack_region(&bottom, &size);
-  return size;
-}
-
 /////////////////////////////////////////////////////////////////////////////
 // helper functions for fatal error handler
 
--- a/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp	Mon Dec 12 21:56:45 2016 -0800
+++ b/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp	Tue Nov 08 16:30:36 2016 +0100
@@ -320,12 +320,6 @@
   return s;
 }
 
-size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
-  // Only enable glibc guard pages for non-Java threads
-  // (Java threads have HotSpot guard pages)
-  return (thr_type == java_thread ? 0 : page_size());
-}
-
 static void current_stack_region(address *bottom, size_t *size) {
   pthread_attr_t attr;
   int res = pthread_getattr_np(pthread_self(), &attr);
@@ -334,7 +328,7 @@
       vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
     }
     else {
-      fatal("pthread_getattr_np failed with errno = %d", res);
+      fatal("pthread_getattr_np failed with error = %d", res);
     }
   }
 
@@ -342,7 +336,7 @@
   size_t stack_bytes;
   res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes);
   if (res != 0) {
-    fatal("pthread_attr_getstack failed with errno = %d", res);
+    fatal("pthread_attr_getstack failed with error = %d", res);
   }
   address stack_top = stack_bottom + stack_bytes;