1 /* Definition for thread-local data handling. NPTL/Alpha 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 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 /* The TP points to the start of the thread blocks. */ 34 # define TLS_DTV_AT_TP 1 35 # define TLS_TCB_AT_TP 0 36 37 /* Get the thread descriptor definition. */ 38 # include <nptl/descr.h> 39 40 typedef struct 41 { 42 dtv_t *dtv; 43 void *__private; 44 } tcbhead_t; 45 46 /* This is the size of the initial TCB. */ 47 # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) 48 49 /* This is the size of the TCB. */ 50 # define TLS_TCB_SIZE sizeof (tcbhead_t) 51 52 /* This is the size we need before TCB. */ 53 # define TLS_PRE_TCB_SIZE sizeof (struct pthread) 54 55 /* Install the dtv pointer. The pointer passed is to the element with 56 index -1 which contain the length. */ 57 # define INSTALL_DTV(tcbp, dtvp) \ 58 (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1) 59 60 /* Install new dtv for current thread. */ 61 # define INSTALL_NEW_DTV(dtv) \ 62 (THREAD_DTV() = (dtv)) 63 64 /* Return dtv of given thread descriptor. */ 65 # define GET_DTV(tcbp) \ 66 (((tcbhead_t *) (tcbp))->dtv) 67 68 /* Code to initially initialize the thread pointer. This might need 69 special attention since 'errno' is not yet available and if the 70 operation can cause a failure 'errno' must not be touched. */ 71 # define TLS_INIT_TP(tcbp) \ 72 (__builtin_set_thread_pointer ((void *)(tcbp)), NULL) 73 74 /* Value passed to 'clone' for initialization of the thread register. */ 75 # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1 76 77 /* Return the address of the dtv for the current thread. */ 78 # define THREAD_DTV() \ 79 (((tcbhead_t *) __builtin_thread_pointer ())->dtv) 80 81 /* Return the thread descriptor for the current thread. */ 82 # define THREAD_SELF \ 83 ((struct pthread *)__builtin_thread_pointer () - 1) 84 85 /* Magic for libthread_db to know how to do THREAD_SELF. */ 86 # define DB_THREAD_SELF \ 87 REGISTER (64, 64, 32 * 8, -sizeof (struct pthread)) 88 89 # include <tcb-access.h> 90 91 /* Get and set the global scope generation counter in struct pthread. */ 92 #define THREAD_GSCOPE_FLAG_UNUSED 0 93 #define THREAD_GSCOPE_FLAG_USED 1 94 #define THREAD_GSCOPE_FLAG_WAIT 2 95 #define THREAD_GSCOPE_RESET_FLAG() \ 96 do \ 97 { int __res \ 98 = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \ 99 THREAD_GSCOPE_FLAG_UNUSED); \ 100 if (__res == THREAD_GSCOPE_FLAG_WAIT) \ 101 lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \ 102 } \ 103 while (0) 104 #define THREAD_GSCOPE_SET_FLAG() \ 105 do \ 106 { \ 107 THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \ 108 atomic_write_barrier (); \ 109 } \ 110 while (0) 111 112 #endif /* __ASSEMBLER__ */ 113 114 #endif /* tls.h */ 115