sysdeps/hppa/nptl/tls.h

   1 /* Definition for thread-local data handling.  NPTL/hppa version.
   2    Copyright (C) 2005, 2007, 2010, 2011 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 <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 #else /* __ASSEMBLER__ */
  42 # include <tcb-offsets.h>
  43 #endif /* __ASSEMBLER__ */
  44
  45 /* Signal that TLS support is available.  */
  46 #define USE_TLS 1
  47
  48 #ifndef __ASSEMBLER__
  49
  50 /* Get system call information.  */
  51 # include <sysdep.h>
  52
  53 /* The TP points to the start of the thread blocks.  */
  54 # define TLS_DTV_AT_TP  1
  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, secondcall) \
  99   ({ __set_cr27(tcbp); NULL; })
 100
 101 /* Return the address of the dtv for the current thread.  */
 102 # define THREAD_DTV() \
 103   ({ tcbhead_t *__tcbp = (tcbhead_t *)__get_cr27();     \
 104         __tcbp->dtv;                                    \
 105    })
 106
 107 /* Return the thread descriptor for the current thread.  */
 108 # define THREAD_SELF \
 109   ({ struct pthread *__self;                    \
 110         __self = __get_cr27();                  \
 111         __self - 1;                             \
 112    })
 113
 114 /* Magic for libthread_db to know how to do THREAD_SELF.
 115    Our thread pointer is stored in cr27.  See asm/elf.h for the offset into
 116    elf_gregset_t.  The thread descriptor is sizeof (struct pthread) away.  */
 117 # define DB_THREAD_SELF \
 118   REGISTER (32, 32, 53 * 4, -sizeof (struct pthread))
 119
 120 /* Access to data in the thread descriptor is easy.  */
 121 # define THREAD_GETMEM(descr, member) \
 122   descr->member
 123 # define THREAD_GETMEM_NC(descr, member, idx) \
 124   descr->member[idx]
 125 # define THREAD_SETMEM(descr, member, value) \
 126   descr->member = (value)
 127 # define THREAD_SETMEM_NC(descr, member, idx, value) \
 128   descr->member[idx] = (value)
 129
 130 static inline struct pthread *__get_cr27(void)
 131 {
 132   long cr27;
 133   asm ("mfctl %%cr27, %0" : "=r" (cr27) : );
 134   return (struct pthread *) cr27;
 135 }
 136
 137 /* We write to cr27, clobber r26 as the input argument, and clobber
 138    r31 as the link register.  */
 139 static inline void __set_cr27(struct pthread *cr27)
 140 {
 141   asm ( "ble    0xe0(%%sr2, %%r0)\n\t"
 142         "copy   %0, %%r26"
 143         : : "r" (cr27) : "r26", "r31" );
 144 }
 145
 146 /* Get and set the global scope generation counter in struct pthread.  */
 147 #define THREAD_GSCOPE_FLAG_UNUSED 0
 148 #define THREAD_GSCOPE_FLAG_USED   1
 149 #define THREAD_GSCOPE_FLAG_WAIT   2
 150 #define THREAD_GSCOPE_RESET_FLAG() \
 151   do                                                                         \
 152     { int __res                                                              \
 153         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 154                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 155       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 156         lll_private_futex_wake (&THREAD_SELF->header.gscope_flag, 1);        \
 157     }                                                                        \
 158   while (0)
 159 #define THREAD_GSCOPE_SET_FLAG() \
 160   do                                                                         \
 161     {                                                                        \
 162       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 163       atomic_write_barrier ();                                               \
 164     }                                                                        \
 165   while (0)
 166 #define THREAD_GSCOPE_WAIT() \
 167   GL(dl_wait_lookup_done) ()
 168
 169 #endif /* !__ASSEMBLER__ */
 170
 171 #endif  /* tls.h */