1 /* Definition for thread-local data handling. NPTL/s390 version. 2 Copyright (C) 2003-2022 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 #ifndef __ASSEMBLER__ 24 # include <stdbool.h> 25 # include <stddef.h> 26 # include <stdint.h> 27 # include <stdlib.h> 28 # include <list.h> 29 # include <kernel-features.h> 30 # include <dl-dtv.h> 31 32 typedef struct 33 { 34 void *tcb; /* Pointer to the TCB. Not necessary the 35 thread descriptor used by libpthread. */ 36 dtv_t *dtv; 37 void *self; /* Pointer to the thread descriptor. */ 38 int multiple_threads; 39 uintptr_t sysinfo; 40 uintptr_t stack_guard; 41 int gscope_flag; 42 int __glibc_reserved1; 43 /* GCC split stack support. */ 44 void *__private_ss; 45 } tcbhead_t; 46 47 # ifndef __s390x__ 48 # define TLS_MULTIPLE_THREADS_IN_TCB 1 49 # endif 50 51 #else /* __ASSEMBLER__ */ 52 # include <tcb-offsets.h> 53 #endif 54 55 56 /* Alignment requirement for the stack. For IA-32 this is governed by 57 the SSE memory functions. */ 58 #define STACK_ALIGN 16 59 60 #ifndef __ASSEMBLER__ 61 /* Get system call information. */ 62 # include <sysdep.h> 63 64 /* This is the size of the initial TCB. Can't be just sizeof (tcbhead_t), 65 because NPTL getpid, __libc_alloca_cutoff etc. need (almost) the whole 66 struct pthread even when not linked with -lpthread. */ 67 # define TLS_INIT_TCB_SIZE sizeof (struct pthread) 68 69 /* This is the size of the TCB. */ 70 # define TLS_TCB_SIZE sizeof (struct pthread) 71 72 /* The TCB can have any size and the memory following the address the 73 thread pointer points to is unspecified. Allocate the TCB there. */ 74 # define TLS_TCB_AT_TP 1 75 # define TLS_DTV_AT_TP 0 76 77 /* Get the thread descriptor definition. */ 78 # include <nptl/descr.h> 79 80 81 /* Install the dtv pointer. The pointer passed is to the element with 82 index -1 which contain the length. */ 83 # define INSTALL_DTV(descr, dtvp) \ 84 ((tcbhead_t *) (descr))->dtv = (dtvp) + 1 85 86 /* Install new dtv for current thread. */ 87 # define INSTALL_NEW_DTV(dtv) \ 88 (((tcbhead_t *) __builtin_thread_pointer ())->dtv = (dtv)) 89 90 /* Return dtv of given thread descriptor. */ 91 # define GET_DTV(descr) \ 92 (((tcbhead_t *) (descr))->dtv) 93 94 #if defined NEED_DL_SYSINFO && defined SHARED 95 # define INIT_SYSINFO \ 96 _head->sysinfo = GLRO(dl_sysinfo) 97 #else 98 # define INIT_SYSINFO 99 #endif 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(thrdescr) \ 105 ({ void *_thrdescr = (thrdescr); \ 106 tcbhead_t *_head = _thrdescr; \ 107 \ 108 _head->tcb = _thrdescr; \ 109 /* For now the thread descriptor is at the same address. */ \ 110 _head->self = _thrdescr; \ 111 /* New syscall handling support. */ \ 112 INIT_SYSINFO; \ 113 \ 114 __builtin_set_thread_pointer (_thrdescr); \ 115 NULL; \ 116 }) 117 118 /* Value passed to 'clone' for initialization of the thread register. */ 119 # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) 120 121 /* Return the address of the dtv for the current thread. */ 122 # define THREAD_DTV() \ 123 (((tcbhead_t *) __builtin_thread_pointer ())->dtv) 124 125 /* Return the thread descriptor for the current thread. */ 126 # define THREAD_SELF ((struct pthread *) __builtin_thread_pointer ()) 127 128 /* Magic for libthread_db to know how to do THREAD_SELF. */ 129 # define DB_THREAD_SELF REGISTER (32, 32, 18 * 4, 0) \ 130 REGISTER (64, __WORDSIZE, 18 * 8, 0) 131 132 # include <tcb-access.h> 133 134 /* Set the stack guard field in TCB head. */ 135 #define THREAD_SET_STACK_GUARD(value) \ 136 do \ 137 { \ 138 __asm__ __volatile__ ("" : : : "a0", "a1"); \ 139 THREAD_SETMEM (THREAD_SELF, header.stack_guard, value); \ 140 } \ 141 while (0) 142 #define THREAD_COPY_STACK_GUARD(descr) \ 143 ((descr)->header.stack_guard \ 144 = THREAD_GETMEM (THREAD_SELF, header.stack_guard)) 145 146 /* s390 doesn't have HP_TIMING_*, so for the time being 147 use stack_guard as pointer_guard. */ 148 #define THREAD_GET_POINTER_GUARD() \ 149 THREAD_GETMEM (THREAD_SELF, header.stack_guard) 150 #define THREAD_SET_POINTER_GUARD(value) ((void) (value)) 151 #define THREAD_COPY_POINTER_GUARD(descr) 152 153 /* Get and set the global scope generation counter in struct pthread. */ 154 #define THREAD_GSCOPE_FLAG_UNUSED 0 155 #define THREAD_GSCOPE_FLAG_USED 1 156 #define THREAD_GSCOPE_FLAG_WAIT 2 157 #define THREAD_GSCOPE_RESET_FLAG() \ 158 do \ 159 { int __res \ 160 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 161 THREAD_GSCOPE_FLAG_UNUSED); \ 162 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 163 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 164 } \ 165 while (0) 166 #define THREAD_GSCOPE_SET_FLAG() \ 167 do \ 168 { \ 169 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 170 atomic_write_barrier (); \ 171 } \ 172 while (0) 173 174 #endif /* __ASSEMBLER__ */ 175 176 #endif /* tls.h */ 177