sysdeps/i386/nptl/pthreaddef.h

   1 /* Copyright (C) 2002-2018 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 /* Default stack size.  */
  20 #define ARCH_STACK_DEFAULT_SIZE (2 * 1024 * 1024)
  21
  22 /* Required stack pointer alignment at beginning.  SSE requires 16
  23    bytes.  */
  24 #define STACK_ALIGN             16
  25
  26 /* Minimal stack size after allocating thread descriptor and guard size.  */
  27 #define MINIMAL_REST_STACK      2048
  28
  29 /* Alignment requirement for TCB.
  30
  31    Some processors such as Intel Atom pay a big penalty on every
  32    access using a segment override if that segment's base is not
  33    aligned to the size of a cache line.  (See Intel 64 and IA-32
  34    Architectures Optimization Reference Manual, section 13.3.3.3,
  35    "Segment Base".)  On such machines, a cache line is 64 bytes.  */
  36 #define TCB_ALIGNMENT           64
  37
  38
  39 /* Location of current stack frame.  */
  40 #define CURRENT_STACK_FRAME     __builtin_frame_address (0)