ports/sysdeps/hppa/nptl/tls.h

   1 /* Definition for thread-local data handling.  NPTL/hppa version.
   2    Copyright (C) 2005-2014 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 #else /* __ASSEMBLER__ */
  41 # include <tcb-offsets.h>
  42 #endif /* __ASSEMBLER__ */
  43
  44 /* Signal that TLS support is available.  */
  45 #define USE_TLS 1
  46
  47 #ifndef __ASSEMBLER__
  48
  49 /* Get system call information.  */
  50 # include <sysdep.h>
  51
  52 /* The TP points to the start of the thread blocks.  */
  53 # define TLS_DTV_AT_TP  1
  54
  55 /* Get the thread descriptor definition.  */
  56 # include <nptl/descr.h>
  57
  58 typedef struct
  59 {
  60   dtv_t *dtv;
  61   void *private;
  62 } tcbhead_t;
  63
  64 /* This is the size of the initial TCB.  */
  65 # define TLS_INIT_TCB_SIZE      sizeof (tcbhead_t)
  66
  67 /* Alignment requirements for the initial TCB.  */
  68 # define TLS_INIT_TCB_ALIGN     __alignof__ (tcbhead_t)
  69
  70 /* This is the size of the TCB.  */
  71 # define TLS_TCB_SIZE           sizeof (tcbhead_t)
  72
  73 /* Alignment requirements for the TCB.  */
  74 # define TLS_TCB_ALIGN          __alignof__ (struct pthread)
  75
  76 /* This is the size we need before TCB */
  77 # define TLS_PRE_TCB_SIZE       sizeof (struct pthread)
  78
  79 /* Install the dtv pointer.  The pointer passed is to the element with
  80    index -1 which contain the length.  */
  81 # define INSTALL_DTV(tcbp, dtvp) \
  82   ((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1
  83
  84 /* Install new dtv for current thread.  */
  85 # define INSTALL_NEW_DTV(dtv) \
  86   ({ tcbhead_t *__tcbp = (tcbhead_t *)__get_cr27();     \
  87         __tcbp->dtv = dtv;                              \
  88    })
  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   ({ __set_cr27(tcbp); NULL; })
  99
 100 /* Return the address of the dtv for the current thread.  */
 101 # define THREAD_DTV() \
 102   ({ tcbhead_t *__tcbp = (tcbhead_t *)__get_cr27();     \
 103         __tcbp->dtv;                                    \
 104    })
 105
 106 /* Return the thread descriptor for the current thread.  */
 107 # define THREAD_SELF \
 108   ({ struct pthread *__self;                    \
 109         __self = __get_cr27();                  \
 110         __self - 1;                             \
 111    })
 112
 113 /* Magic for libthread_db to know how to do THREAD_SELF.
 114    Our thread pointer is stored in cr27.  See asm/elf.h for the offset into
 115    elf_gregset_t.  The thread descriptor is sizeof (struct pthread) away.  */
 116 # define DB_THREAD_SELF \
 117   REGISTER (32, 32, 53 * 4, -sizeof (struct pthread))
 118
 119 /* Access to data in the thread descriptor is easy.  */
 120 # define THREAD_GETMEM(descr, member) \
 121   descr->member
 122 # define THREAD_GETMEM_NC(descr, member, idx) \
 123   descr->member[idx]
 124 # define THREAD_SETMEM(descr, member, value) \
 125   descr->member = (value)
 126 # define THREAD_SETMEM_NC(descr, member, idx, value) \
 127   descr->member[idx] = (value)
 128
 129 static inline struct pthread *__get_cr27(void)
 130 {
 131   long cr27;
 132   asm ("mfctl %%cr27, %0" : "=r" (cr27) : );
 133   return (struct pthread *) cr27;
 134 }
 135
 136 /* We write to cr27, clobber r26 as the input argument, and clobber
 137    r31 as the link register.  */
 138 static inline void __set_cr27(struct pthread *cr27)
 139 {
 140   asm ( "ble    0xe0(%%sr2, %%r0)\n\t"
 141         "copy   %0, %%r26"
 142         : : "r" (cr27) : "r26", "r31" );
 143 }
 144
 145 /* Get and set the global scope generation counter in struct pthread.  */
 146 #define THREAD_GSCOPE_FLAG_UNUSED 0
 147 #define THREAD_GSCOPE_FLAG_USED   1
 148 #define THREAD_GSCOPE_FLAG_WAIT   2
 149 #define THREAD_GSCOPE_RESET_FLAG() \
 150   do                                                                         \
 151     { int __res                                                              \
 152         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 153                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 154       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 155         lll_private_futex_wake (&THREAD_SELF->header.gscope_flag, 1);        \
 156     }                                                                        \
 157   while (0)
 158 #define THREAD_GSCOPE_SET_FLAG() \
 159   do                                                                         \
 160     {                                                                        \
 161       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 162       atomic_write_barrier ();                                               \
 163     }                                                                        \
 164   while (0)
 165 #define THREAD_GSCOPE_WAIT() \
 166   GL(dl_wait_lookup_done) ()
 167
 168 #endif /* !__ASSEMBLER__ */
 169
 170 #endif  /* tls.h */