1 /* Definition for thread-local data handling. NPTL/MIPS version. 2 Copyright (C) 2005-2021 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 _TLS_H 20 #define _TLS_H 1 21 22 #include <dl-sysdep.h> 23 24 #ifndef __ASSEMBLER__ 25 # include <stdbool.h> 26 # include <stddef.h> 27 # include <stdint.h> 28 # include <dl-dtv.h> 29 30 /* Get system call information. */ 31 # include <sysdep.h> 32 33 #ifdef __mips16 34 /* MIPS16 uses GCC builtin to access the TP. */ 35 # define READ_THREAD_POINTER() (__builtin_thread_pointer ()) 36 #else 37 /* Note: rd must be $v1 to be ABI-conformant. */ 38 # if defined (__mips_isa_rev) && __mips_isa_rev >= 2 39 # define READ_THREAD_POINTER() \ 40 ({ void *__result; \ 41 asm volatile ("rdhwr\t%0, $29" : "=v" (__result)); \ 42 __result; }) 43 # else 44 # define READ_THREAD_POINTER() \ 45 ({ void *__result; \ 46 asm volatile (".set\tpush\n\t.set\tmips32r2\n\t" \ 47 "rdhwr\t%0, $29\n\t.set\tpop" : "=v" (__result)); \ 48 __result; }) 49 # endif 50 #endif 51 52 #else /* __ASSEMBLER__ */ 53 # if __mips_isa_rev >= 2 54 # define READ_THREAD_POINTER(rd) rdhwr rd, $29 55 # else 56 # define READ_THREAD_POINTER(rd) \ 57 .set push; \ 58 .set mips32r2; \ 59 rdhwr rd, $29; \ 60 .set pop 61 # endif 62 #endif /* __ASSEMBLER__ */ 63 64 65 #ifndef __ASSEMBLER__ 66 67 /* The TP points to the start of the thread blocks. */ 68 # define TLS_DTV_AT_TP 1 69 # define TLS_TCB_AT_TP 0 70 71 /* Get the thread descriptor definition. */ 72 # include <nptl/descr.h> 73 74 typedef struct 75 { 76 dtv_t *dtv; 77 void *private; 78 } tcbhead_t; 79 80 /* This is the size of the initial TCB. Because our TCB is before the thread 81 pointer, we don't need this. */ 82 # define TLS_INIT_TCB_SIZE 0 83 84 /* This is the size of the TCB. Because our TCB is before the thread 85 pointer, we don't need this. */ 86 # define TLS_TCB_SIZE 0 87 88 /* This is the size we need before TCB - actually, it includes the TCB. */ 89 # define TLS_PRE_TCB_SIZE \ 90 (sizeof (struct pthread) \ 91 + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \ 92 & ~(__alignof (struct pthread) - 1))) 93 94 /* The thread pointer (in hardware register $29) points to the end of 95 the TCB + 0x7000, as for PowerPC. The pthread_descr structure is 96 immediately in front of the TCB. */ 97 # define TLS_TCB_OFFSET 0x7000 98 99 /* Install the dtv pointer. The pointer passed is to the element with 100 index -1 which contain the length. */ 101 # define INSTALL_DTV(tcbp, dtvp) \ 102 (((tcbhead_t *) (tcbp))[-1].dtv = (dtvp) + 1) 103 104 /* Install new dtv for current thread. */ 105 # define INSTALL_NEW_DTV(dtv) \ 106 (THREAD_DTV() = (dtv)) 107 108 /* Return dtv of given thread descriptor. */ 109 # define GET_DTV(tcbp) \ 110 (((tcbhead_t *) (tcbp))[-1].dtv) 111 112 /* Code to initially initialize the thread pointer. This might need 113 special attention since 'errno' is not yet available and if the 114 operation can cause a failure 'errno' must not be touched. */ 115 # define TLS_INIT_TP(tcbp) \ 116 ({ long int result_var; \ 117 result_var = INTERNAL_SYSCALL_CALL (set_thread_area, \ 118 (char *) (tcbp) + TLS_TCB_OFFSET); \ 119 INTERNAL_SYSCALL_ERROR_P (result_var) \ 120 ? "unknown error" : NULL; }) 121 122 /* Value passed to 'clone' for initialization of the thread register. */ 123 # define TLS_DEFINE_INIT_TP(tp, pd) \ 124 void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE 125 126 /* Return the address of the dtv for the current thread. */ 127 # define THREAD_DTV() \ 128 (((tcbhead_t *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET))[-1].dtv) 129 130 /* Return the thread descriptor for the current thread. */ 131 # define THREAD_SELF \ 132 ((struct pthread *) (READ_THREAD_POINTER () \ 133 - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)) 134 135 /* Magic for libthread_db to know how to do THREAD_SELF. */ 136 # define DB_THREAD_SELF \ 137 CONST_THREAD_AREA (32, TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE) 138 139 /* Access to data in the thread descriptor is easy. */ 140 # include <tcb-access.h> 141 142 /* l_tls_offset == 0 is perfectly valid on MIPS, so we have to use some 143 different value to mean unset l_tls_offset. */ 144 # define NO_TLS_OFFSET -1 145 146 /* 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_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 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) 166 167 #endif /* __ASSEMBLER__ */ 168 169 #endif /* tls.h */ 170