sysdeps/hppa/nptl/tls.h

   1 /* Definition for thread-local data handling.  NPTL/hppa version.
   2    Copyright (C) 2005-2015 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 # define TLS_TCB_AT_TP  0
  55
  56 /* Get the thread descriptor definition.  */
  57 # include <nptl/descr.h>
  58
  59 typedef struct
  60 {
  61   dtv_t *dtv;
  62   void *private;
  63 } tcbhead_t;
  64
  65 /* This is the size of the initial TCB.  */
  66 # define TLS_INIT_TCB_SIZE      sizeof (tcbhead_t)
  67
  68 /* Alignment requirements for the initial TCB.  */
  69 # define TLS_INIT_TCB_ALIGN     __alignof__ (tcbhead_t)
  70
  71 /* This is the size of the TCB.  */
  72 # define TLS_TCB_SIZE           sizeof (tcbhead_t)
  73
  74 /* Alignment requirements for the TCB.  */
  75 # define TLS_TCB_ALIGN          __alignof__ (struct pthread)
  76
  77 /* This is the size we need before TCB */
  78 # define TLS_PRE_TCB_SIZE       sizeof (struct pthread)
  79
  80 /* Install the dtv pointer.  The pointer passed is to the element with
  81    index -1 which contain the length.  */
  82 # define INSTALL_DTV(tcbp, dtvp) \
  83   ((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1
  84
  85 /* Install new dtv for current thread.  */
  86 # define INSTALL_NEW_DTV(dtv) \
  87   ({ tcbhead_t *__tcbp = (tcbhead_t *)__get_cr27();     \
  88         __tcbp->dtv = dtv;                              \
  89    })
  90
  91 /* Return dtv of given thread descriptor.  */
  92 # define GET_DTV(tcbp) \
  93   (((tcbhead_t *) (tcbp))->dtv)
  94
  95 /* Code to initially initialize the thread pointer.  This might need
  96    special attention since 'errno' is not yet available and if the
  97    operation can cause a failure 'errno' must not be touched.  */
  98 # define TLS_INIT_TP(tcbp) \
  99   ({ __set_cr27(tcbp); NULL; })
 100
 101 /* Value passed to 'clone' for initialization of the thread register.  */
 102 # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1
 103
 104 /* Return the address of the dtv for the current thread.  */
 105 # define THREAD_DTV() \
 106   ({ tcbhead_t *__tcbp = (tcbhead_t *)__get_cr27();     \
 107         __tcbp->dtv;                                    \
 108    })
 109
 110 /* Return the thread descriptor for the current thread.  */
 111 # define THREAD_SELF \
 112   ({ struct pthread *__self;                    \
 113         __self = __get_cr27();                  \
 114         __self - 1;                             \
 115    })
 116
 117 /* Magic for libthread_db to know how to do THREAD_SELF.
 118    Our thread pointer is stored in cr27.  See asm/elf.h for the offset into
 119    elf_gregset_t.  The thread descriptor is sizeof (struct pthread) away.  */
 120 # define DB_THREAD_SELF \
 121   REGISTER (32, 32, 53 * 4, -sizeof (struct pthread))
 122
 123 /* Access to data in the thread descriptor is easy.  */
 124 # define THREAD_GETMEM(descr, member) \
 125   descr->member
 126 # define THREAD_GETMEM_NC(descr, member, idx) \
 127   descr->member[idx]
 128 # define THREAD_SETMEM(descr, member, value) \
 129   descr->member = (value)
 130 # define THREAD_SETMEM_NC(descr, member, idx, value) \
 131   descr->member[idx] = (value)
 132
 133 static inline struct pthread *__get_cr27(void)
 134 {
 135   long cr27;
 136   asm ("mfctl %%cr27, %0" : "=r" (cr27) : );
 137   return (struct pthread *) cr27;
 138 }
 139
 140 /* We write to cr27, clobber r26 as the input argument, and clobber
 141    r31 as the link register.  */
 142 static inline void __set_cr27(struct pthread *cr27)
 143 {
 144   asm ( "ble    0xe0(%%sr2, %%r0)\n\t"
 145         "copy   %0, %%r26"
 146         : : "r" (cr27) : "r26", "r31" );
 147 }
 148
 149 /* Get and set the global scope generation counter in struct pthread.  */
 150 #define THREAD_GSCOPE_FLAG_UNUSED 0
 151 #define THREAD_GSCOPE_FLAG_USED   1
 152 #define THREAD_GSCOPE_FLAG_WAIT   2
 153 #define THREAD_GSCOPE_RESET_FLAG() \
 154   do                                                                         \
 155     { int __res                                                              \
 156         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 157                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 158       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 159         lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE);   \
 160     }                                                                        \
 161   while (0)
 162 #define THREAD_GSCOPE_SET_FLAG() \
 163   do                                                                         \
 164     {                                                                        \
 165       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 166       atomic_write_barrier ();                                               \
 167     }                                                                        \
 168   while (0)
 169 #define THREAD_GSCOPE_WAIT() \
 170   GL(dl_wait_lookup_done) ()
 171
 172 #endif /* !__ASSEMBLER__ */
 173
 174 #endif  /* tls.h */