1 /* Definition for thread-local data handling. NPTL/ARM version. 2 Copyright (C) 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, see 17 <http://www.gnu.org/licenses/>. */ 18 19 #ifndef _TLS_H 20 #define _TLS_H 1 21 22 #ifndef __ASSEMBLER__ 23 24 # include <stdbool.h> 25 # include <stddef.h> 26 # include <stdint.h> 27 28 /* Type for the dtv. */ 29 typedef union dtv 30 { 31 size_t counter; 32 struct 33 { 34 void *val; 35 bool is_static; 36 } pointer; 37 } dtv_t; 38 39 #else /* __ASSEMBLER__ */ 40 # include <tcb-offsets.h> 41 #endif /* __ASSEMBLER__ */ 42 43 44 /* We require TLS support in the tools. */ 45 #define HAVE_TLS_SUPPORT 1 46 #define HAVE_TLS_MODEL_ATTRIBUTE 1 47 #define HAVE___THREAD 1 48 49 /* Signal that TLS support is available. */ 50 #define USE_TLS 1 51 52 #ifndef __ASSEMBLER__ 53 54 /* Get system call information. */ 55 # include <sysdep.h> 56 57 /* The TP points to the start of the thread blocks. */ 58 # define TLS_DTV_AT_TP 1 59 60 /* Get the thread descriptor definition. */ 61 # include <../../descr.h> 62 63 typedef struct 64 { 65 dtv_t *dtv; 66 void *private; 67 } tcbhead_t; 68 69 /* This is the size of the initial TCB. */ 70 # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) 71 72 /* Alignment requirements for the initial TCB. */ 73 # define TLS_INIT_TCB_ALIGN 16 74 75 /* This is the size of the TCB. */ 76 # define TLS_TCB_SIZE sizeof (tcbhead_t) 77 78 /* This is the size we need before TCB. */ 79 # define TLS_PRE_TCB_SIZE sizeof (struct pthread) 80 81 /* Alignment requirements for the TCB. */ 82 # define TLS_TCB_ALIGN 16 83 84 /* Install the dtv pointer. The pointer passed is to the element with 85 index -1 which contain the length. */ 86 # define INSTALL_DTV(tcbp, dtvp) \ 87 (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1) 88 89 /* Install new dtv for current thread. */ 90 # define INSTALL_NEW_DTV(dtv) \ 91 (THREAD_DTV() = (dtv)) 92 93 /* Return dtv of given thread descriptor. */ 94 # define GET_DTV(tcbp) \ 95 (((tcbhead_t *) (tcbp))->dtv) 96 97 /* Code to initially initialize the thread pointer. This might need 98 special attention since 'errno' is not yet available and if the 99 operation can cause a failure 'errno' must not be touched. */ 100 # define TLS_INIT_TP(tcbp, secondcall) \ 101 ({ INTERNAL_SYSCALL_DECL (err); \ 102 long result_var; \ 103 result_var = INTERNAL_SYSCALL_ARM (set_tls, err, 1, (tcbp)); \ 104 INTERNAL_SYSCALL_ERROR_P (result_var, err) \ 105 ? "unknown error" : NULL; }) 106 107 /* Return the address of the dtv for the current thread. */ 108 # define THREAD_DTV() \ 109 (((tcbhead_t *) __builtin_thread_pointer ())->dtv) 110 111 /* Return the thread descriptor for the current thread. */ 112 # define THREAD_SELF \ 113 ((struct pthread *)__builtin_thread_pointer () - 1) 114 115 /* Magic for libthread_db to know how to do THREAD_SELF. */ 116 # define DB_THREAD_SELF \ 117 CONST_THREAD_AREA (32, 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 /* Initializing the thread pointer will generate a SIGILL if the syscall 130 is not available. */ 131 #define TLS_INIT_TP_EXPENSIVE 1 132 133 /* Get and set the global scope generation counter in struct pthread. */ 134 #define THREAD_GSCOPE_FLAG_UNUSED 0 135 #define THREAD_GSCOPE_FLAG_USED 1 136 #define THREAD_GSCOPE_FLAG_WAIT 2 137 #define THREAD_GSCOPE_RESET_FLAG() \ 138 do \ 139 { int __res \ 140 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 141 THREAD_GSCOPE_FLAG_UNUSED); \ 142 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 143 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 144 } \ 145 while (0) 146 #define THREAD_GSCOPE_SET_FLAG() \ 147 do \ 148 { \ 149 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 150 atomic_write_barrier (); \ 151 } \ 152 while (0) 153 #define THREAD_GSCOPE_WAIT() \ 154 GL(dl_wait_lookup_done) () 155 156 #endif /* __ASSEMBLER__ */ 157 158 #endif /* tls.h */ 159