nptl/sysdeps/s390/tls.h

   1 /* Definition for thread-local data handling.  NPTL/s390 version.
   2    Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _TLS_H
  21 #define _TLS_H  1
  22
  23 #include <dl-sysdep.h>
  24 #ifndef __ASSEMBLER__
  25 # include <stdbool.h>
  26 # include <stddef.h>
  27 # include <stdint.h>
  28 # include <stdlib.h>
  29 # include <list.h>
  30
  31
  32 /* Type for the dtv.  */
  33 typedef union dtv
  34 {
  35   size_t counter;
  36   struct
  37   {
  38     void *val;
  39     bool is_static;
  40   } pointer;
  41 } dtv_t;
  42
  43
  44 typedef struct
  45 {
  46   void *tcb;            /* Pointer to the TCB.  Not necessary the
  47                            thread descriptor used by libpthread.  */
  48   dtv_t *dtv;
  49   void *self;           /* Pointer to the thread descriptor.  */
  50   int multiple_threads;
  51   uintptr_t sysinfo;
  52   uintptr_t stack_guard;
  53 } tcbhead_t;
  54
  55 # ifndef __s390x__
  56 #  define TLS_MULTIPLE_THREADS_IN_TCB 1
  57 # endif
  58
  59 #else /* __ASSEMBLER__ */
  60 # include <tcb-offsets.h>
  61 #endif
  62
  63
  64 /* We require TLS support in the tools.  */
  65 #ifndef HAVE_TLS_SUPPORT
  66 # error "TLS support is required."
  67 #endif
  68
  69 /* Signal that TLS support is available.  */
  70 #define USE_TLS 1
  71
  72 /* Alignment requirement for the stack.  For IA-32 this is governed by
  73    the SSE memory functions.  */
  74 #define STACK_ALIGN     16
  75
  76 #ifndef __ASSEMBLER__
  77 /* Get system call information.  */
  78 # include <sysdep.h>
  79
  80 /* Get the thread descriptor definition.  */
  81 # include <nptl/descr.h>
  82
  83 /* This is the size of the initial TCB.  Can't be just sizeof (tcbhead_t),
  84    because NPTL getpid, __libc_alloca_cutoff etc. need (almost) the whole
  85    struct pthread even when not linked with -lpthread.  */
  86 # define TLS_INIT_TCB_SIZE sizeof (struct pthread)
  87
  88 /* Alignment requirements for the initial TCB.  */
  89 # define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
  90
  91 /* This is the size of the TCB.  */
  92 # define TLS_TCB_SIZE sizeof (struct pthread)
  93
  94 /* Alignment requirements for the TCB.  */
  95 # define TLS_TCB_ALIGN __alignof__ (struct pthread)
  96
  97 /* The TCB can have any size and the memory following the address the
  98    thread pointer points to is unspecified.  Allocate the TCB there.  */
  99 # define TLS_TCB_AT_TP  1
 100
 101
 102 /* Install the dtv pointer.  The pointer passed is to the element with
 103    index -1 which contain the length.  */
 104 #  define INSTALL_DTV(descr, dtvp) \
 105   ((tcbhead_t *) (descr))->dtv = (dtvp) + 1
 106
 107 /* Install new dtv for current thread.  */
 108 #  define INSTALL_NEW_DTV(dtv) \
 109   (((tcbhead_t *) __builtin_thread_pointer ())->dtv = (dtv))
 110
 111 /* Return dtv of given thread descriptor.  */
 112 #  define GET_DTV(descr) \
 113   (((tcbhead_t *) (descr))->dtv)
 114
 115 #if defined NEED_DL_SYSINFO && defined SHARED
 116 # define INIT_SYSINFO \
 117   _head->sysinfo = GLRO(dl_sysinfo)
 118 #else
 119 # define INIT_SYSINFO
 120 #endif
 121
 122 /* Code to initially initialize the thread pointer.  This might need
 123    special attention since 'errno' is not yet available and if the
 124    operation can cause a failure 'errno' must not be touched.  */
 125 # define TLS_INIT_TP(thrdescr, secondcall) \
 126   ({ void *_thrdescr = (thrdescr);                                            \
 127      tcbhead_t *_head = _thrdescr;                                            \
 128                                                                               \
 129      _head->tcb = _thrdescr;                                                  \
 130      /* For now the thread descriptor is at the same address.  */             \
 131      _head->self = _thrdescr;                                                 \
 132      /* New syscall handling support.  */                                     \
 133      INIT_SYSINFO;                                                            \
 134                                                                               \
 135     __builtin_set_thread_pointer (_thrdescr);                                 \
 136     NULL;                                                                     \
 137   })
 138
 139 /* Return the address of the dtv for the current thread.  */
 140 #  define THREAD_DTV() \
 141   (((tcbhead_t *) __builtin_thread_pointer ())->dtv)
 142
 143 /* Return the thread descriptor for the current thread.  */
 144 # define THREAD_SELF ((struct pthread *) __builtin_thread_pointer ())
 145
 146 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 147 # define DB_THREAD_SELF REGISTER (32, 32, 18 * 4, 0) \
 148                         REGISTER (64, __WORDSIZE, 18 * 8, 0)
 149
 150 /* Access to data in the thread descriptor is easy.  */
 151 #define THREAD_GETMEM(descr, member) \
 152   descr->member
 153 #define THREAD_GETMEM_NC(descr, member, idx) \
 154   descr->member[idx]
 155 #define THREAD_SETMEM(descr, member, value) \
 156   descr->member = (value)
 157 #define THREAD_SETMEM_NC(descr, member, idx, value) \
 158   descr->member[idx] = (value)
 159
 160 /* Set the stack guard field in TCB head.  */
 161 #define THREAD_SET_STACK_GUARD(value) \
 162   THREAD_SETMEM (THREAD_SELF, header.stack_guard, value)
 163 #define THREAD_COPY_STACK_GUARD(descr) \
 164   ((descr)->header.stack_guard                                                \
 165    = THREAD_GETMEM (THREAD_SELF, header.stack_guard))
 166
 167 #endif /* __ASSEMBLER__ */
 168
 169 #endif  /* tls.h */