1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002 Daniel Eischen <deischen@freebsd.org>. 5 * Copyright (c) 2005 David Xu <davidxu@freebsd.org>. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 /* 33 * Machine-dependent thread prototypes/definitions. 34 */ 35 #ifndef _PTHREAD_MD_H_ 36 #define _PTHREAD_MD_H_ 37 38 #include <stddef.h> 39 #include <sys/types.h> 40 #include <machine/sysarch.h> 41 42 #define CPU_SPINWAIT __asm __volatile("pause") 43 44 #define DTV_OFFSET offsetof(struct tcb, tcb_dtv) 45 46 /* 47 * Variant II tcb, first two members are required by rtld, 48 * %gs points to the structure. 49 */ 50 struct tcb { 51 struct tcb *tcb_self; /* required by rtld */ 52 void *tcb_dtv; /* required by rtld */ 53 struct pthread *tcb_thread; 54 }; 55 56 /* 57 * Evaluates to the byte offset of the per-tcb variable name. 58 */ 59 #define __tcb_offset(name) __offsetof(struct tcb, name) 60 61 /* 62 * Evaluates to the type of the per-tcb variable name. 63 */ 64 #define __tcb_type(name) __typeof(((struct tcb *)0)->name) 65 66 /* 67 * Evaluates to the value of the per-tcb variable name. 68 */ 69 #define TCB_GET32(name) ({ \ 70 __tcb_type(name) __result; \ 71 \ 72 u_int __i; \ 73 __asm __volatile("movl %%gs:%1, %0" \ 74 : "=r" (__i) \ 75 : "m" (*(volatile u_int *)(__tcb_offset(name)))); \ 76 __result = (__tcb_type(name))__i; \ 77 \ 78 __result; \ 79 }) 80 81 /* Called from the thread to set its private data. */ 82 static __inline void 83 _tcb_set(struct tcb *tcb) 84 { 85 i386_set_gsbase(tcb); 86 } 87 88 /* Get the current kcb. */ 89 static __inline struct tcb * 90 _tcb_get(void) 91 { 92 return (TCB_GET32(tcb_self)); 93 } 94 95 /* Get the current thread. */ 96 static __inline struct pthread * 97 _get_curthread(void) 98 { 99 return (TCB_GET32(tcb_thread)); 100 } 101 102 #define HAS__UMTX_OP_ERR 1 103 104 #endif 105