linuxthreads/sysdeps/ia64/tls.h

   1 /* Definitions for thread-local data handling.  linuxthreads/IA-64 version.
   2    Copyright (C) 2002, 2003, 2004 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
  22
  23 #ifndef __ASSEMBLER__
  24
  25 # include <dl-sysdep.h>
  26 # include <pt-machine.h>
  27 # include <stddef.h>
  28
  29 /* Type for the dtv.  */
  30 typedef union dtv
  31 {
  32   size_t counter;
  33   void *pointer;
  34 } dtv_t;
  35
  36 #else /* __ASSEMBLER__ */
  37 # include <tcb-offsets.h>
  38 #endif /* __ASSEMBLER__ */
  39
  40 #ifdef HAVE_TLS_SUPPORT
  41
  42 /* Signal that TLS support is available.  */
  43 # define USE_TLS        1
  44
  45 # ifndef __ASSEMBLER__
  46
  47 typedef struct
  48 {
  49   dtv_t *dtv;
  50   void *private;
  51 } tcbhead_t;
  52
  53 /* This is the size of the initial TCB.  */
  54 #  define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
  55
  56 /* Alignment requirements for the initial TCB.  */
  57 #  define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
  58
  59 /* This is the size of the TCB.  */
  60 #  define TLS_TCB_SIZE sizeof (tcbhead_t)
  61
  62 /* This is the size we need before TCB.  */
  63 #  define TLS_PRE_TCB_SIZE sizeof (struct _pthread_descr_struct)
  64
  65 /* Alignment requirements for the TCB.  */
  66 #  define TLS_TCB_ALIGN __alignof__ (struct _pthread_descr_struct)
  67
  68 /* The DTV is allocated at the TP; the TCB is placed elsewhere.  */
  69 #  define TLS_DTV_AT_TP 1
  70
  71 /* Install the dtv pointer.  The pointer passed is to the element with
  72    index -1 which contain the length.  */
  73 #  define INSTALL_DTV(tcbp, dtvp) \
  74   ((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1
  75
  76 /* Install new dtv for current thread.  */
  77 #  define INSTALL_NEW_DTV(DTV) \
  78   (((tcbhead_t *)__thread_self)->dtv = (DTV))
  79
  80 /* Return dtv of given thread descriptor.  */
  81 #  define GET_DTV(tcbp) \
  82   (((tcbhead_t *) (tcbp))->dtv)
  83
  84 #if defined NEED_DL_SYSINFO
  85 # define INIT_SYSINFO \
  86   (((tcbhead_t *) __thread_self)->private = (void *) GLRO(dl_sysinfo))
  87 #else
  88 # define INIT_SYSINFO 0
  89 #endif
  90
  91 /* Code to initially initialize the thread pointer.  This might need
  92    special attention since 'errno' is not yet available and if the
  93    operation can cause a failure 'errno' must not be touched.  */
  94 #  define TLS_INIT_TP(tcbp, secondcall) \
  95   (__thread_self = (__typeof (__thread_self)) (tcbp), INIT_SYSINFO, NULL)
  96
  97 /* Return the address of the dtv for the current thread.  */
  98 #  define THREAD_DTV() \
  99   (((tcbhead_t *)__thread_self)->dtv)
 100
 101 /* Return the thread descriptor for the current thread.  */
 102 #  undef THREAD_SELF
 103 #  define THREAD_SELF (__thread_self - 1)
 104
 105 #  undef INIT_THREAD_SELF
 106 #  define INIT_THREAD_SELF(descr, nr) \
 107   (__thread_self = (struct _pthread_descr_struct *)(descr) + 1)
 108
 109 # define TLS_MULTIPLE_THREADS_IN_TCB 1
 110
 111 /* Get the thread descriptor definition.  */
 112 #  include <linuxthreads/descr.h>
 113
 114 # endif
 115
 116 #else
 117
 118 # ifndef __ASSEMBLER__
 119
 120 typedef struct
 121 {
 122   void *tcb;
 123   dtv_t *dtv;
 124   void *self;
 125   int multiple_threads;
 126 } tcbhead_t;
 127
 128 /* Get the thread descriptor definition.  */
 129 #  include <linuxthreads/descr.h>
 130
 131 #  define NONTLS_INIT_TP \
 132   do {                                                                  \
 133     static const tcbhead_t nontls_init_tp = { .multiple_threads = 0 };  \
 134     __thread_self = (__typeof (__thread_self)) &nontls_init_tp;         \
 135   } while (0)
 136
 137 #endif
 138
 139 #endif /* USE_TLS */
 140
 141 #endif  /* tls.h */