1 /* Definition for thread-local data handling. NPTL/m68k version. 2 Copyright (C) 2010-2022 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 #endif /* __ASSEMBLER__ */ 30 31 #ifndef __ASSEMBLER__ 32 33 /* Get system call information. */ 34 # include <sysdep.h> 35 36 /* The TP points to the start of the thread blocks. */ 37 # define TLS_DTV_AT_TP 1 38 # define TLS_TCB_AT_TP 0 39 40 /* Get the thread descriptor definition. */ 41 # include <nptl/descr.h> 42 43 typedef struct 44 { 45 dtv_t *dtv; 46 void *private; 47 } tcbhead_t; 48 49 /* This is the size of the initial TCB. Because our TCB is before the thread 50 pointer, we don't need this. */ 51 # define TLS_INIT_TCB_SIZE 0 52 53 /* This is the size of the TCB. Because our TCB is before the thread 54 pointer, we don't need this. */ 55 # define TLS_TCB_SIZE 0 56 57 /* This is the size we need before TCB - actually, it includes the TCB. */ 58 # define TLS_PRE_TCB_SIZE \ 59 (sizeof (struct pthread) \ 60 + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \ 61 & ~(__alignof (struct pthread) - 1))) 62 63 /* The thread pointer (TP) points to the end of the 64 TCB + 0x7000, as for PowerPC and MIPS. This implies that TCB address is 65 TP - 0x7000. As we define TLS_DTV_AT_TP we can 66 assume that the pthread struct is allocated immediately ahead of the 67 TCB. This implies that the pthread_descr address is 68 TP - (TLS_PRE_TCB_SIZE + 0x7000). */ 69 # define TLS_TCB_OFFSET 0x7000 70 71 /* Install the dtv pointer. The pointer passed is to the element with 72 index -1 which contain the length. */ 73 # define INSTALL_DTV(tcbp, dtvp) \ 74 ((tcbhead_t *) (tcbp))[-1].dtv = dtvp + 1 75 76 /* Install new dtv for current thread. */ 77 # define INSTALL_NEW_DTV(dtv) \ 78 (THREAD_DTV () = (dtv)) 79 80 /* Return dtv of given thread descriptor. */ 81 # define GET_DTV(tcbp) \ 82 (((tcbhead_t *) (tcbp))[-1].dtv) 83 84 /* Code to initially initialize the thread pointer. This might need 85 special attention since 'errno' is not yet available and if the 86 operation can cause a failure 'errno' must not be touched. */ 87 # define TLS_INIT_TP(tcbp) \ 88 ({ \ 89 int _sys_result; \ 90 \ 91 _sys_result = INTERNAL_SYSCALL_CALL (set_thread_area, \ 92 ((void *) (tcbp)) + TLS_TCB_OFFSET); \ 93 INTERNAL_SYSCALL_ERROR_P (_sys_result) ? "unknown error" : NULL; }) 94 95 # define TLS_DEFINE_INIT_TP(tp, pd) \ 96 void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE 97 98 extern void * __m68k_read_tp (void); 99 100 /* Return the address of the dtv for the current thread. */ 101 # define THREAD_DTV() \ 102 (((tcbhead_t *) (__m68k_read_tp () - TLS_TCB_OFFSET))[-1].dtv) 103 104 /* Return the thread descriptor for the current thread. */ 105 # define THREAD_SELF \ 106 ((struct pthread *) (__m68k_read_tp () - 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, TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE) 111 112 # include <tcb-access.h> 113 114 /* l_tls_offset == 0 is perfectly valid on M68K, so we have to use some 115 different value to mean unset l_tls_offset. */ 116 # define NO_TLS_OFFSET -1 117 118 /* Get and set the global scope generation counter in struct pthread. */ 119 #define THREAD_GSCOPE_FLAG_UNUSED 0 120 #define THREAD_GSCOPE_FLAG_USED 1 121 #define THREAD_GSCOPE_FLAG_WAIT 2 122 #define THREAD_GSCOPE_RESET_FLAG() \ 123 do \ 124 { int __res \ 125 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 126 THREAD_GSCOPE_FLAG_UNUSED); \ 127 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 128 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 129 } \ 130 while (0) 131 #define THREAD_GSCOPE_SET_FLAG() \ 132 do \ 133 { \ 134 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 135 atomic_write_barrier (); \ 136 } \ 137 while (0) 138 139 #endif /* __ASSEMBLER__ */ 140 141 #endif /* tls.h */ 142