1 /* Definitions for thread-local data handling. NPTL/C-SKY version. 2 Copyright (C) 2018-2021 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 #ifndef __ASSEMBLER__ 23 24 # include <stdbool.h> 25 # include <stddef.h> 26 # include <stdint.h> 27 # include <dl-dtv.h> 28 29 /* Define r31 as thread pointer register. */ 30 # define READ_THREAD_POINTER() \ 31 ({ void *__result; \ 32 __asm__ __volatile__ ("mov %0, r31" \ 33 : "=r" (__result)); \ 34 __result; }) 35 36 #else 37 /* Define r31 as thread pointer register. */ 38 # define READ_THREAD_POINTER() \ 39 mov r0, r31; 40 #endif /* __ASSEMBLER__ */ 41 42 #ifndef __ASSEMBLER__ 43 44 /* Get system call information. */ 45 # include <sysdep.h> 46 47 /* The TP points to the start of the thread blocks. */ 48 # define TLS_DTV_AT_TP 1 49 # define TLS_TCB_AT_TP 0 50 51 /* Get the thread descriptor definition. */ 52 # include <nptl/descr.h> 53 54 typedef struct 55 { 56 dtv_t *dtv; 57 void *private; 58 } tcbhead_t; 59 60 /* This is the size of the initial TCB. */ 61 # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) 62 63 /* This is the size of the TCB. */ 64 # define TLS_TCB_SIZE sizeof (tcbhead_t) 65 66 /* This is the size we need before TCB. */ 67 # define TLS_PRE_TCB_SIZE sizeof (struct pthread) 68 69 /* The thread pointer tp points to the end of the TCB. 70 The pthread_descr structure is immediately in front of the TCB. */ 71 # define TLS_TCB_OFFSET 0 72 73 /* Install the dtv pointer. The pointer passed is to the element with 74 index -1 which contain the length. */ 75 # define INSTALL_DTV(tcbp, dtvp) \ 76 (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1) 77 78 /* Install new dtv for current thread. */ 79 # define INSTALL_NEW_DTV(dtv) \ 80 (THREAD_DTV() = (dtv)) 81 82 /* Return dtv of given thread descriptor. */ 83 # define GET_DTV(tcbp) \ 84 (((tcbhead_t *) (tcbp))->dtv) 85 86 # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1 87 88 /* Code to initially initialize the thread pointer. This might need 89 special attention since 'errno' is not yet available and if the 90 operation can cause a failure 'errno' must not be touched. */ 91 # define TLS_INIT_TP(tcbp) \ 92 ({ long int result_var; \ 93 result_var = INTERNAL_SYSCALL_CALL (set_thread_area, \ 94 (char *) (tcbp) + TLS_TCB_OFFSET); \ 95 INTERNAL_SYSCALL_ERROR_P (result_var) \ 96 ? "unknown error" : NULL; }) 97 98 /* Return the address of the dtv for the current thread. */ 99 # define THREAD_DTV() \ 100 (((tcbhead_t *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET))->dtv) 101 102 /* Return the thread descriptor for the current thread. */ 103 # undef THREAD_SELF 104 # define THREAD_SELF \ 105 ((struct pthread *) (READ_THREAD_POINTER () \ 106 - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)) 107 108 /* Magic for libthread_db to know how to do THREAD_SELF. */ 109 # define DB_THREAD_SELF \ 110 CONST_THREAD_AREA (32, sizeof (struct pthread)) 111 112 # include <tcb-access.h> 113 114 /* Get and set the global scope generation counter in struct pthread. */ 115 # define THREAD_GSCOPE_FLAG_UNUSED 0 116 # define THREAD_GSCOPE_FLAG_USED 1 117 # define THREAD_GSCOPE_FLAG_WAIT 2 118 # define THREAD_GSCOPE_RESET_FLAG() \ 119 do \ 120 { int __res \ 121 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 122 THREAD_GSCOPE_FLAG_UNUSED); \ 123 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 124 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 125 } \ 126 while (0) 127 # define THREAD_GSCOPE_SET_FLAG() \ 128 do \ 129 { \ 130 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 131 atomic_write_barrier (); \ 132 } \ 133 while (0) 134 135 #endif /* __ASSEMBLER__ */ 136 137 #endif /* tls.h */ 138