1 /* Definition for thread-local data handling. NPTL/Nios II version. 2 Copyright (C) 2012-2022 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 #else /* __ASSEMBLER__ */ 31 # include <tcb-offsets.h> 32 #endif /* __ASSEMBLER__ */ 33 34 35 #ifndef __ASSEMBLER__ 36 37 /* Get system call information. */ 38 # include <sysdep.h> 39 40 /* The TP points to the start of the thread blocks. */ 41 # define TLS_DTV_AT_TP 1 42 # define TLS_TCB_AT_TP 0 43 44 /* Get the thread descriptor definition. */ 45 # include <nptl/descr.h> 46 47 typedef struct 48 { 49 dtv_t *dtv; 50 uintptr_t pointer_guard; 51 unsigned spare[6]; 52 } tcbhead_t; 53 54 register struct pthread *__thread_self __asm__("r23"); 55 56 #define READ_THREAD_POINTER() ((void *) __thread_self) 57 58 /* This is the size of the initial TCB. Because our TCB is before the thread 59 pointer, we don't need this. */ 60 # define TLS_INIT_TCB_SIZE 0 61 62 /* This is the size of the TCB. Because our TCB is before the thread 63 pointer, we don't need this. */ 64 # define TLS_TCB_SIZE 0 65 66 /* This is the size we need before TCB - actually, it includes the TCB. */ 67 # define TLS_PRE_TCB_SIZE \ 68 (sizeof (struct pthread) \ 69 + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \ 70 & ~(__alignof (struct pthread) - 1))) 71 72 /* The thread pointer (in hardware register r23) points to the end of 73 the TCB + 0x7000, as for PowerPC and MIPS. */ 74 # define TLS_TCB_OFFSET 0x7000 75 76 /* Install the dtv pointer. The pointer passed is to the element with 77 index -1 which contain the length. */ 78 # define INSTALL_DTV(tcbp, dtvp) \ 79 (((tcbhead_t *) (tcbp))[-1].dtv = (dtvp) + 1) 80 81 /* Install new dtv for current thread. */ 82 # define INSTALL_NEW_DTV(dtv) \ 83 (THREAD_DTV() = (dtv)) 84 85 /* Return dtv of given thread descriptor. */ 86 # define GET_DTV(tcbp) \ 87 (((tcbhead_t *) (tcbp))[-1].dtv) 88 89 /* Code to initially initialize the thread pointer. */ 90 # define TLS_INIT_TP(tcbp) \ 91 (__thread_self = (struct pthread *) ((char *) tcbp + TLS_TCB_OFFSET), NULL) 92 93 /* Value passed to 'clone' for initialization of the thread register. */ 94 # define TLS_DEFINE_INIT_TP(tp, pd) \ 95 void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE 96 97 /* Return the address of the dtv for the current thread. */ 98 # define THREAD_DTV() \ 99 (((tcbhead_t *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET))[-1].dtv) 100 101 /* Return the thread descriptor for the current thread. */ 102 # define THREAD_SELF \ 103 ((struct pthread *) (READ_THREAD_POINTER () \ 104 - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)) 105 106 /* Magic for libthread_db to know how to do THREAD_SELF. */ 107 # define DB_THREAD_SELF \ 108 REGISTER (32, 32, 23 * 4, -TLS_PRE_TCB_SIZE - TLS_TCB_OFFSET) 109 110 # include <tcb-access.h> 111 112 # define THREAD_GET_POINTER_GUARD() \ 113 (((tcbhead_t *) (READ_THREAD_POINTER () \ 114 - TLS_TCB_OFFSET))[-1].pointer_guard) 115 # define THREAD_SET_POINTER_GUARD(value) \ 116 (THREAD_GET_POINTER_GUARD () = (value)) 117 # define THREAD_COPY_POINTER_GUARD(descr) \ 118 (((tcbhead_t *) ((void *) (descr) \ 119 + TLS_PRE_TCB_SIZE))[-1].pointer_guard \ 120 = THREAD_GET_POINTER_GUARD()) 121 122 /* l_tls_offset == 0 is perfectly valid on Nios II, so we have to use some 123 different value to mean unset l_tls_offset. */ 124 # define NO_TLS_OFFSET -1 125 126 /* Get and set the global scope generation counter in struct pthread. */ 127 #define THREAD_GSCOPE_FLAG_UNUSED 0 128 #define THREAD_GSCOPE_FLAG_USED 1 129 #define THREAD_GSCOPE_FLAG_WAIT 2 130 #define THREAD_GSCOPE_RESET_FLAG() \ 131 do \ 132 { int __res \ 133 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 134 THREAD_GSCOPE_FLAG_UNUSED); \ 135 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 136 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 137 } \ 138 while (0) 139 #define THREAD_GSCOPE_SET_FLAG() \ 140 do \ 141 { \ 142 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 143 atomic_write_barrier (); \ 144 } \ 145 while (0) 146 147 #endif /* __ASSEMBLER__ */ 148 149 #endif /* tls.h */ 150