1 /* Definition for thread-local data handling. NPTL/Meta version. 2 Copyright (C) 2003, 2005, 2006, 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; see the file COPYING.LIB. If 17 not, see <http://www.gnu.org/licenses/>. */ 18 19 #ifndef _TLS_H 20 #define _TLS_H 21 22 #ifndef __ASSEMBLER__ 23 # include <stdbool.h> 24 # include <stddef.h> 25 # include <stdint.h> 26 # include <stdlib.h> 27 # include <list.h> 28 # include <sysdep.h> 29 # include <bits/kernel-features.h> 30 31 /* Type for the dtv. */ 32 typedef union dtv 33 { 34 size_t counter; 35 struct 36 { 37 void *val; 38 bool is_static; 39 } pointer; 40 } dtv_t; 41 42 typedef struct 43 { 44 dtv_t *dtv; 45 uintptr_t pointer_guard; 46 } tcbhead_t; 47 48 # define TLS_MULTIPLE_THREADS_IN_TCB 1 49 50 #else /* __ASSEMBLER__ */ 51 # include <tcb-offsets.h> 52 #endif /* __ASSEMBLER__ */ 53 54 55 /* We require TLS support in the tools. */ 56 #define HAVE_TLS_SUPPORT 57 #define HAVE___THREAD 1 58 #define HAVE_TLS_MODEL_ATTRIBUTE 1 59 /* Signal that TLS support is available. */ 60 # define USE_TLS 1 61 62 #ifndef __ASSEMBLER__ 63 64 /* Get system call information. */ 65 # include <sysdep.h> 66 67 /* This is the size of the initial TCB. */ 68 # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) 69 70 /* Alignment requirements for the initial TCB. */ 71 # define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t) 72 73 /* This is the size of the TCB. */ 74 # define TLS_TCB_SIZE sizeof (tcbhead_t) 75 76 /* This is the size we need before TCB. */ 77 # define TLS_PRE_TCB_SIZE sizeof (struct pthread) 78 79 /* Alignment requirements for the TCB. */ 80 # define TLS_TCB_ALIGN __alignof__ (struct pthread) 81 82 /* The TLS blocks start right after the TCB. */ 83 # define TLS_DTV_AT_TP 1 84 85 /* Get the thread descriptor definition. */ 86 # include <descr.h> 87 88 /* Install the dtv pointer. The pointer passed is to the element with 89 index -1 which contain the length. */ 90 # define INSTALL_DTV(tcbp, dtvp) \ 91 ((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1 92 93 /* Install new dtv for current thread. */ 94 # define INSTALL_NEW_DTV(dtv) \ 95 (((tcbhead_t *)__builtin_thread_pointer ())->dtv = (dtv)) 96 97 /* Return dtv of given thread descriptor. */ 98 # define GET_DTV(tcbp) \ 99 (((tcbhead_t *) (tcbp))->dtv) 100 101 /* Code to initially initialize the thread pointer. This might need 102 special attention since 'errno' is not yet available and if the 103 operation can cause a failure 'errno' must not be touched. */ 104 # define TLS_INIT_TP(tcbp, secondcall) \ 105 ({ INTERNAL_SYSCALL_DECL (err); \ 106 long result_var; \ 107 result_var = INTERNAL_SYSCALL (metag_set_tls, err, 1, (tcbp)); \ 108 INTERNAL_SYSCALL_ERROR_P (result_var, err) \ 109 ? "unknown error" : NULL; }) 110 111 /* Return the address of the dtv for the current thread. */ 112 # define THREAD_DTV() \ 113 (((tcbhead_t *)__builtin_thread_pointer ())->dtv) 114 115 /* Return the thread descriptor for the current thread. 116 The contained asm must *not* be marked volatile since otherwise 117 assignments like 118 struct pthread *self = thread_self(); 119 do not get optimized away. */ 120 # define THREAD_SELF \ 121 ((struct pthread *)__builtin_thread_pointer () - 1) 122 123 /* Magic for libthread_db to know how to do THREAD_SELF. */ 124 # define DB_THREAD_SELF \ 125 CONST_THREAD_AREA (32, sizeof (struct pthread)) 126 127 /* Access to data in the thread descriptor is easy. */ 128 #define THREAD_GETMEM(descr, member) \ 129 descr->member 130 #define THREAD_GETMEM_NC(descr, member, idx) \ 131 descr->member[idx] 132 #define THREAD_SETMEM(descr, member, value) \ 133 descr->member = (value) 134 #define THREAD_SETMEM_NC(descr, member, idx, value) \ 135 descr->member[idx] = (value) 136 137 /* Get and set the global scope generation counter in struct pthread. */ 138 #define THREAD_GSCOPE_FLAG_UNUSED 0 139 #define THREAD_GSCOPE_FLAG_USED 1 140 #define THREAD_GSCOPE_FLAG_WAIT 2 141 #define THREAD_GSCOPE_RESET_FLAG() \ 142 do \ 143 { int __res \ 144 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 145 THREAD_GSCOPE_FLAG_UNUSED); \ 146 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 147 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 148 } \ 149 while (0) 150 #define THREAD_GSCOPE_SET_FLAG() \ 151 do \ 152 { \ 153 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 154 atomic_write_barrier (); \ 155 } \ 156 while (0) 157 #define THREAD_GSCOPE_WAIT() \ 158 GL(dl_wait_lookup_done) () 159 160 #endif /* __ASSEMBLER__ */ 161 162 #endif /* tls.h */ 163