1 /* Definition for thread-local data handling. NPTL/MIPS 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 # include <stdbool.h> 24 # include <stddef.h> 25 # include <stdint.h> 26 27 /* Type for the dtv. */ 28 typedef union dtv 29 { 30 size_t counter; 31 struct 32 { 33 void *val; 34 bool is_static; 35 } pointer; 36 } dtv_t; 37 38 /* Note: rd must be $v1 to be ABI-conformant. */ 39 # define READ_THREAD_POINTER() \ 40 ({ void *__result; \ 41 __asm__ __volatile__ (".set\tpush\n\t.set\tmips32r2\n\t" \ 42 "rdhwr\t%0, $29\n\t.set\tpop" : "=v" (__result)); \ 43 __result; }) 44 45 #else /* __ASSEMBLER__ */ 46 # include <tcb-offsets.h> 47 48 # define READ_THREAD_POINTER(rd) \ 49 .set push; \ 50 .set mips32r2; \ 51 rdhwr rd, $29; \ 52 .set pop 53 #endif /* __ASSEMBLER__ */ 54 55 56 /* We require TLS support in the tools. */ 57 #define HAVE_TLS_SUPPORT 1 58 #define HAVE_TLS_MODEL_ATTRIBUTE 1 59 #define HAVE___THREAD 1 60 61 /* Signal that TLS support is available. */ 62 #define USE_TLS 1 63 64 #ifndef __ASSEMBLER__ 65 66 /* Get system call information. */ 67 # include <sysdep.h> 68 69 /* The TP points to the start of the thread blocks. */ 70 # define TLS_DTV_AT_TP 1 71 72 /* Get the thread descriptor definition. */ 73 #include <../../descr.h> 74 75 typedef struct 76 { 77 dtv_t *dtv; 78 void *private; 79 } tcbhead_t; 80 81 /* This is the size of the initial TCB. Because our TCB is before the thread 82 pointer, we don't need this. */ 83 # define TLS_INIT_TCB_SIZE 0 84 85 /* Alignment requirements for the initial TCB. */ 86 # define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread) 87 88 /* This is the size of the TCB. Because our TCB is before the thread 89 pointer, we don't need this. */ 90 # define TLS_TCB_SIZE 0 91 92 /* Alignment requirements for the TCB. */ 93 # define TLS_TCB_ALIGN __alignof__ (struct pthread) 94 95 /* This is the size we need before TCB - actually, it includes the TCB. */ 96 # define TLS_PRE_TCB_SIZE \ 97 (sizeof (struct pthread) \ 98 + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1))) 99 100 /* The thread pointer (in hardware register $29) points to the end of 101 the TCB + 0x7000, as for PowerPC. The pthread_descr structure is 102 immediately in front of the TCB. */ 103 # define TLS_TCB_OFFSET 0x7000 104 105 /* Install the dtv pointer. The pointer passed is to the element with 106 index -1 which contain the length. */ 107 # define INSTALL_DTV(tcbp, dtvp) \ 108 (((tcbhead_t *) (tcbp))[-1].dtv = (dtvp) + 1) 109 110 /* Install new dtv for current thread. */ 111 # define INSTALL_NEW_DTV(dtv) \ 112 (THREAD_DTV() = (dtv)) 113 114 /* Return dtv of given thread descriptor. */ 115 # define GET_DTV(tcbp) \ 116 (((tcbhead_t *) (tcbp))[-1].dtv) 117 118 /* Code to initially initialize the thread pointer. This might need 119 special attention since 'errno' is not yet available and if the 120 operation can cause a failure 'errno' must not be touched. */ 121 # define TLS_INIT_TP(tcbp, secondcall) \ 122 ({ INTERNAL_SYSCALL_DECL (err); \ 123 long result_var attribute_unused; \ 124 result_var = INTERNAL_SYSCALL (set_thread_area, err, 1, \ 125 (char *) (tcbp) + TLS_TCB_OFFSET); \ 126 INTERNAL_SYSCALL_ERROR_P (result_var, err) \ 127 ? "unknown error" : NULL; }) 128 129 /* Return the address of the dtv for the current thread. */ 130 # define THREAD_DTV() \ 131 (((tcbhead_t *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET))[-1].dtv) 132 133 /* Return the thread descriptor for the current thread. */ 134 # define THREAD_SELF \ 135 ((struct pthread *) (READ_THREAD_POINTER () \ 136 - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)) 137 138 /* Magic for libthread_db to know how to do THREAD_SELF. */ 139 # define DB_THREAD_SELF \ 140 CONST_THREAD_AREA (32, TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE) 141 142 /* Access to data in the thread descriptor is easy. */ 143 # define THREAD_GETMEM(descr, member) \ 144 descr->member 145 # define THREAD_GETMEM_NC(descr, member, idx) \ 146 descr->member[idx] 147 # define THREAD_SETMEM(descr, member, value) \ 148 descr->member = (value) 149 # define THREAD_SETMEM_NC(descr, member, idx, value) \ 150 descr->member[idx] = (value) 151 152 /* l_tls_offset == 0 is perfectly valid on MIPS, so we have to use some 153 different value to mean unset l_tls_offset. */ 154 # define NO_TLS_OFFSET -1 155 /* Get and set the global scope generation counter in struct pthread. */ 156 #define THREAD_GSCOPE_FLAG_UNUSED 0 157 #define THREAD_GSCOPE_FLAG_USED 1 158 #define THREAD_GSCOPE_FLAG_WAIT 2 159 #define THREAD_GSCOPE_RESET_FLAG() \ 160 do \ 161 { int __res \ 162 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 163 THREAD_GSCOPE_FLAG_UNUSED); \ 164 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 165 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 166 } \ 167 while (0) 168 #define THREAD_GSCOPE_SET_FLAG() \ 169 do \ 170 { \ 171 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 172 atomic_write_barrier (); \ 173 } \ 174 while (0) 175 #define THREAD_GSCOPE_WAIT() \ 176 GL(dl_wait_lookup_done) () 177 178 #endif /* __ASSEMBLER__ */ 179 180 #endif /* tls.h */ 181