sysdeps/alpha/nptl/tls.h

   1 /* Definition for thread-local data handling.  NPTL/Alpha version.
   2    Copyright (C) 2003-2014 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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _TLS_H
  20 #define _TLS_H  1
  21
  22 # include <dl-sysdep.h>
  23
  24 #ifndef __ASSEMBLER__
  25 # include <stdbool.h>
  26 # include <stddef.h>
  27 # include <stdint.h>
  28
  29 /* Type for the dtv.  */
  30 typedef union dtv
  31 {
  32   size_t counter;
  33   struct
  34   {
  35     void *val;
  36     bool is_static;
  37   } pointer;
  38 } dtv_t;
  39
  40 /* Get system call information.  */
  41 # include <sysdep.h>
  42
  43 /* The TP points to the start of the thread blocks.  */
  44 # define TLS_DTV_AT_TP  1
  45 # define TLS_TCB_AT_TP  0
  46
  47 /* Get the thread descriptor definition.  */
  48 # include <nptl/descr.h>
  49
  50 typedef struct
  51 {
  52   dtv_t *dtv;
  53   void *__private;
  54 } tcbhead_t;
  55
  56 /* This is the size of the initial TCB.  */
  57 # define TLS_INIT_TCB_SIZE      sizeof (tcbhead_t)
  58
  59 /* Alignment requirements for the initial TCB.  */
  60 # define TLS_INIT_TCB_ALIGN     16
  61
  62 /* This is the size of the TCB.  */
  63 # define TLS_TCB_SIZE           sizeof (tcbhead_t)
  64
  65 /* This is the size we need before TCB.  */
  66 # define TLS_PRE_TCB_SIZE       sizeof (struct pthread)
  67
  68 /* Alignment requirements for the TCB.  */
  69 # define TLS_TCB_ALIGN          16
  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   (THREAD_DTV() = (dtv))
  79
  80 /* Return dtv of given thread descriptor.  */
  81 # define GET_DTV(tcbp) \
  82   (((tcbhead_t *) (tcbp))->dtv)
  83
  84 /* Code to initially initialize the thread pointer.  This might need
  85    special attention since 'errno' is not yet available and if the
  86    operation can cause a failure 'errno' must not be touched.  */
  87 # define TLS_INIT_TP(tcbp) \
  88   (__builtin_set_thread_pointer ((void *)(tcbp)), NULL)
  89
  90 /* Value passed to 'clone' for initialization of the thread register.  */
  91 # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1
  92
  93 /* Return the address of the dtv for the current thread.  */
  94 # define THREAD_DTV() \
  95   (((tcbhead_t *) __builtin_thread_pointer ())->dtv)
  96
  97 /* Return the thread descriptor for the current thread.  */
  98 # define THREAD_SELF \
  99  ((struct pthread *)__builtin_thread_pointer () - 1)
 100
 101 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 102 # define DB_THREAD_SELF \
 103   REGISTER (64, 64, 32 * 8, -sizeof (struct pthread))
 104
 105 /* Access to data in the thread descriptor is easy.  */
 106 #define THREAD_GETMEM(descr, member) \
 107   descr->member
 108 #define THREAD_GETMEM_NC(descr, member, idx) \
 109   descr->member[idx]
 110 #define THREAD_SETMEM(descr, member, value) \
 111   descr->member = (value)
 112 #define THREAD_SETMEM_NC(descr, member, idx, value) \
 113   descr->member[idx] = (value)
 114
 115 /* Get and set the global scope generation counter in struct pthread.  */
 116 #define THREAD_GSCOPE_FLAG_UNUSED 0
 117 #define THREAD_GSCOPE_FLAG_USED   1
 118 #define THREAD_GSCOPE_FLAG_WAIT   2
 119 #define THREAD_GSCOPE_RESET_FLAG() \
 120   do                                                                         \
 121     { int __res                                                              \
 122         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 123                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 124       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 125         lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE);   \
 126     }                                                                        \
 127   while (0)
 128 #define THREAD_GSCOPE_SET_FLAG() \
 129   do                                                                         \
 130     {                                                                        \
 131       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 132       atomic_write_barrier ();                                               \
 133     }                                                                        \
 134   while (0)
 135 #define THREAD_GSCOPE_WAIT() \
 136   GL(dl_wait_lookup_done) ()
 137
 138 #else /* __ASSEMBLER__ */
 139 # include <tcb-offsets.h>
 140 #endif /* __ASSEMBLER__ */
 141
 142 #endif  /* tls.h */