sysdeps/arc/nptl/tls.h

   1 /* Definition for thread-local data handling.  NPTL/ARC version.
   2    Copyright (C) 2020-2021 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    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _ARC_NPTL_TLS_H
  20 #define _ARC_NPTL_TLS_H 1
  21
  22 #include <dl-sysdep.h>
  23
  24 #ifndef __ASSEMBLER__
  25
  26 # include <stdbool.h>
  27 # include <stddef.h>
  28 # include <stdint.h>
  29
  30 #include <dl-dtv.h>
  31
  32 /* Get system call information.  */
  33 # include <sysdep.h>
  34
  35 /* The TLS blocks start right after the TCB.  */
  36 # define TLS_DTV_AT_TP  1
  37 # define TLS_TCB_AT_TP  0
  38
  39 /* Get the thread descriptor definition.  */
  40 # include <nptl/descr.h>
  41
  42 typedef struct
  43 {
  44   dtv_t *dtv;
  45   uintptr_t pointer_guard;
  46 } tcbhead_t;
  47
  48 /* This is the size of the initial TCB.  */
  49 # define TLS_INIT_TCB_SIZE      sizeof (tcbhead_t)
  50
  51 /* Alignment requirements for the initial TCB.  */
  52 # define TLS_INIT_TCB_ALIGN     __alignof__ (struct pthread)
  53
  54 /* This is the size of the TCB.  */
  55 #ifndef TLS_TCB_SIZE
  56 # define TLS_TCB_SIZE           sizeof (tcbhead_t)
  57 #endif
  58
  59 /* Alignment requirements for the TCB.  */
  60 # define TLS_TCB_ALIGN          __alignof__ (struct pthread)
  61
  62 /* This is the size we need before TCB.  */
  63 # define TLS_PRE_TCB_SIZE       sizeof (struct pthread)
  64
  65 /* Install the dtv pointer.  The pointer passed is to the element with
  66    index -1 which contain the length.  */
  67 # define INSTALL_DTV(tcbp, dtvp) \
  68   (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1)
  69
  70 /* Install new dtv for current thread.  */
  71 # define INSTALL_NEW_DTV(dtv) \
  72   (THREAD_DTV() = (dtv))
  73
  74 /* Return dtv of given thread descriptor.  */
  75 # define GET_DTV(tcbp) \
  76   (((tcbhead_t *) (tcbp))->dtv)
  77
  78 /* Code to initially initialize the thread pointer.  */
  79 # define TLS_INIT_TP(tcbp)                                      \
  80   ({                                                            \
  81         long result_var;                                        \
  82         __builtin_set_thread_pointer (tcbp);                    \
  83         result_var = INTERNAL_SYSCALL_CALL (arc_settls, (tcbp));\
  84         INTERNAL_SYSCALL_ERROR_P (result_var)                   \
  85           ? "settls syscall error" : NULL;                      \
  86    })
  87
  88 /* Value passed to 'clone' for initialization of the thread register.  */
  89 # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1
  90
  91 /* Return the address of the dtv for the current thread.  */
  92 # define THREAD_DTV() \
  93   (((tcbhead_t *) __builtin_thread_pointer ())->dtv)
  94
  95 /* Return the thread descriptor for the current thread.  */
  96 # define THREAD_SELF \
  97  ((struct pthread *)__builtin_thread_pointer () - 1)
  98
  99 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 100 # define DB_THREAD_SELF \
 101   CONST_THREAD_AREA (32, sizeof (struct pthread))
 102
 103 # include <tcb-access.h>
 104
 105 /* Get and set the global scope generation counter in struct pthread.  */
 106 #define THREAD_GSCOPE_FLAG_UNUSED 0
 107 #define THREAD_GSCOPE_FLAG_USED   1
 108 #define THREAD_GSCOPE_FLAG_WAIT   2
 109 #define THREAD_GSCOPE_RESET_FLAG() \
 110   do                                                                         \
 111     { int __res                                                              \
 112         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 113                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 114       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 115         lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE);   \
 116     }                                                                        \
 117   while (0)
 118 #define THREAD_GSCOPE_SET_FLAG() \
 119   do                                                                         \
 120     {                                                                        \
 121       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 122       atomic_write_barrier ();                                               \
 123     }                                                                        \
 124   while (0)
 125
 126 #endif /* !__ASSEMBLER__ */
 127
 128 #endif  /* tls.h */