nptl/sysdeps/sh/tls.h

   1 /* Definition for thread-local data handling.  NPTL/SH version.
   2    Copyright (C) 2003, 2005, 2007 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 # include <dl-sysdep.h>
  24
  25 #ifndef __ASSEMBLER__
  26 # include <stdbool.h>
  27 # include <stddef.h>
  28 # include <stdint.h>
  29
  30 /* Type for the dtv.  */
  31 typedef union dtv
  32 {
  33   size_t counter;
  34   struct
  35   {
  36     void *val;
  37     bool is_static;
  38   } pointer;
  39 } dtv_t;
  40
  41 typedef struct
  42 {
  43   dtv_t *dtv;
  44   uintptr_t pointer_guard;
  45 } tcbhead_t;
  46
  47 # define TLS_MULTIPLE_THREADS_IN_TCB 1
  48
  49 #else /* __ASSEMBLER__ */
  50 # include <tcb-offsets.h>
  51 #endif /* __ASSEMBLER__ */
  52
  53
  54 /* We require TLS support in the tools.  */
  55 #ifndef HAVE_TLS_SUPPORT
  56 # error "TLS support is required."
  57 #endif
  58
  59 /* Signal that TLS support is available.  */
  60 # define USE_TLS        1
  61
  62 #ifndef __ASSEMBLER__
  63
  64 /* Get system call information.  */
  65 # include <sysdep.h>
  66
  67 /* This is the size of the initial TCB.  */
  68 # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
  69
  70 /* Alignment requirements for the initial TCB.  */
  71 # define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
  72
  73 /* This is the size of the TCB.  */
  74 # define TLS_TCB_SIZE sizeof (tcbhead_t)
  75
  76 /* This is the size we need before TCB.  */
  77 # define TLS_PRE_TCB_SIZE sizeof (struct pthread)
  78
  79 /* Alignment requirements for the TCB.  */
  80 # define TLS_TCB_ALIGN __alignof__ (struct pthread)
  81
  82 /* The TLS blocks start right after the TCB.  */
  83 # define TLS_DTV_AT_TP  1
  84
  85 /* Get the thread descriptor definition.  */
  86 # include <nptl/descr.h>
  87
  88 /* Install the dtv pointer.  The pointer passed is to the element with
  89    index -1 which contain the length.  */
  90 # define INSTALL_DTV(tcbp, dtvp) \
  91   ((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1
  92
  93 /* Install new dtv for current thread.  */
  94 # define INSTALL_NEW_DTV(dtv) \
  95   ({ tcbhead_t *__tcbp;                                                       \
  96      __asm __volatile ("stc gbr,%0" : "=r" (__tcbp));                         \
  97      __tcbp->dtv = (dtv);})
  98
  99 /* Return dtv of given thread descriptor.  */
 100 # define GET_DTV(tcbp) \
 101   (((tcbhead_t *) (tcbp))->dtv)
 102
 103 /* Code to initially initialize the thread pointer.  This might need
 104    special attention since 'errno' is not yet available and if the
 105    operation can cause a failure 'errno' must not be touched.  */
 106 # define TLS_INIT_TP(tcbp, secondcall) \
 107   ({ __asm __volatile ("ldc %0,gbr" : : "r" (tcbp)); 0; })
 108
 109 /* Return the address of the dtv for the current thread.  */
 110 # define THREAD_DTV() \
 111   ({ tcbhead_t *__tcbp;                                                       \
 112      __asm __volatile ("stc gbr,%0" : "=r" (__tcbp));                         \
 113      __tcbp->dtv;})
 114
 115 /* Return the thread descriptor for the current thread.
 116    The contained asm must *not* be marked volatile since otherwise
 117    assignments like
 118         struct pthread *self = thread_self();
 119    do not get optimized away.  */
 120 # define THREAD_SELF \
 121   ({ struct pthread *__self;                                                  \
 122      __asm ("stc gbr,%0" : "=r" (__self));                                    \
 123      __self - 1;})
 124
 125 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 126 # define DB_THREAD_SELF \
 127   REGISTER (32, 32, REG_GBR * 4, -sizeof (struct pthread))
 128
 129 /* Read member of the thread descriptor directly.  */
 130 # define THREAD_GETMEM(descr, member) (descr->member)
 131
 132 /* Same as THREAD_GETMEM, but the member offset can be non-constant.  */
 133 # define THREAD_GETMEM_NC(descr, member, idx) (descr->member[idx])
 134
 135 /* Set member of the thread descriptor directly.  */
 136 # define THREAD_SETMEM(descr, member, value) \
 137     descr->member = (value)
 138
 139 /* Same as THREAD_SETMEM, but the member offset can be non-constant.  */
 140 # define THREAD_SETMEM_NC(descr, member, idx, value) \
 141     descr->member[idx] = (value)
 142
 143 #define THREAD_GET_POINTER_GUARD() \
 144   ({ tcbhead_t *__tcbp;                                                       \
 145      __asm __volatile ("stc gbr,%0" : "=r" (__tcbp));                         \
 146      __tcbp->pointer_guard;})
 147  #define THREAD_SET_POINTER_GUARD(value) \
 148   ({ tcbhead_t *__tcbp;                                                       \
 149      __asm __volatile ("stc gbr,%0" : "=r" (__tcbp));                         \
 150      __tcbp->pointer_guard = (value);})
 151 #define THREAD_COPY_POINTER_GUARD(descr) \
 152   ({ tcbhead_t *__tcbp;                                                       \
 153      __asm __volatile ("stc gbr,%0" : "=r" (__tcbp));                         \
 154      ((tcbhead_t *) (descr + 1))->pointer_guard = __tcbp->pointer_guard;})
 155
 156 /* Get and set the global scope generation counter in struct pthread.  */
 157 #define THREAD_GSCOPE_FLAG_UNUSED 0
 158 #define THREAD_GSCOPE_FLAG_USED   1
 159 #define THREAD_GSCOPE_FLAG_WAIT   2
 160 #define THREAD_GSCOPE_RESET_FLAG() \
 161   do                                                                         \
 162     { int __res                                                              \
 163         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 164                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 165       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 166         lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);                \
 167     }                                                                        \
 168   while (0)
 169 #define THREAD_GSCOPE_SET_FLAG() \
 170   do                                                                         \
 171     {                                                                        \
 172       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 173       atomic_write_barrier ();                                               \
 174     }                                                                        \
 175   while (0)
 176 #define THREAD_GSCOPE_WAIT() \
 177   GL(dl_wait_lookup_done) ()
 178
 179 #endif /* __ASSEMBLER__ */
 180
 181 #endif  /* tls.h */