nptl/sysdeps/alpha/tls.h

   1 /* Definition for thread-local data handling.  NPTL/Alpha version.
   2    Copyright (C) 2003 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
  25 #ifndef __ASSEMBLER__
  26 # include <stddef.h>
  27 # include <stdint.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
  41 /* We require TLS support in the tools.  */
  42 #ifndef HAVE_TLS_SUPPORT
  43 # error "TLS support is required."
  44 #endif
  45
  46 /* Signal that TLS support is available.  */
  47 # define USE_TLS        1
  48
  49 #ifndef __ASSEMBLER__
  50
  51 /* Get system call information.  */
  52 # include <sysdep.h>
  53
  54 /* The TP points to the start of the thread blocks.  */
  55 # define TLS_DTV_AT_TP  1
  56
  57 /* Get the thread descriptor definition.  */
  58 # include <nptl/descr.h>
  59
  60 typedef struct
  61 {
  62   dtv_t *dtv;
  63   void *private;
  64 } tcbhead_t;
  65
  66 /* This is the size of the initial TCB.  */
  67 # define TLS_INIT_TCB_SIZE      sizeof (tcbhead_t)
  68
  69 /* Alignment requirements for the initial TCB.  */
  70 # define TLS_INIT_TCB_ALIGN     16
  71
  72 /* This is the size of the TCB.  */
  73 # define TLS_TCB_SIZE           sizeof (tcbhead_t)
  74
  75 /* This is the size we need before TCB.  */
  76 # define TLS_PRE_TCB_SIZE       sizeof (struct pthread)
  77
  78 /* Alignment requirements for the TCB.  */
  79 # define TLS_TCB_ALIGN          16
  80
  81 /* Install the dtv pointer.  The pointer passed is to the element with
  82    index -1 which contain the length.  */
  83 # define INSTALL_DTV(tcbp, dtvp) \
  84   (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1)
  85
  86 /* Install new dtv for current thread.  */
  87 # define INSTALL_NEW_DTV(dtv) \
  88   (THREAD_DTV() = (dtv))
  89
  90 /* Return dtv of given thread descriptor.  */
  91 # define GET_DTV(tcbp) \
  92   (((tcbhead_t *) (tcbp))->dtv)
  93
  94 /* Code to initially initialize the thread pointer.  This might need
  95    special attention since 'errno' is not yet available and if the
  96    operation can cause a failure 'errno' must not be touched.  */
  97 # define TLS_INIT_TP(tcbp, secondcall) \
  98   (__builtin_set_thread_pointer ((void *)(tcbp)), NULL)
  99
 100 /* Return the address of the dtv for the current thread.  */
 101 # define THREAD_DTV() \
 102   (((tcbhead_t *) __builtin_thread_pointer ())->dtv)
 103
 104 /* Return the thread descriptor for the current thread.  */
 105 # define THREAD_SELF \
 106  ((struct pthread *)__builtin_thread_pointer () - 1)
 107
 108 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 109 # define DB_THREAD_SELF \
 110   REGISTER (64, 64, 32 * 8, -sizeof (struct pthread))
 111
 112 /* Access to data in the thread descriptor is easy.  */
 113 #define THREAD_GETMEM(descr, member) \
 114   descr->member
 115 #define THREAD_GETMEM_NC(descr, member, idx) \
 116   descr->member[idx]
 117 #define THREAD_SETMEM(descr, member, value) \
 118   descr->member = (value)
 119 #define THREAD_SETMEM_NC(descr, member, idx, value) \
 120   descr->member[idx] = (value)
 121
 122 #endif /* __ASSEMBLER__ */
 123
 124 #endif  /* tls.h */