src/os_cpu/linux_ppc/vm/os_linux_ppc.cpp

rev 12363 : 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
rev 12364 : imported patch compilerGuardFix.patch

*** 533,551 ****
  }
  
  ////////////////////////////////////////////////////////////////////////////////
  // thread stack
  
! // 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
  size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
!   // default stack size (compiler thread needs larger stack)
    size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K);
    return s;
  }
  
  /////////////////////////////////////////////////////////////////////////////
--- 533,551 ----
  }
  
  ////////////////////////////////////////////////////////////////////////////////
  // thread stack
  
! // Minimum usable stack sizes required to get to user code. Space for
! // HotSpot guard pages is added later.
! size_t os::Posix::_compiler_thread_min_stack_allowed = 64 * K;
! size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;
! size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
  
! // 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).
    size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K);
    return s;
  }
  
  /////////////////////////////////////////////////////////////////////////////