pthread_md.h revision 145578
1/*- 2 * Copyright (c) 2002 Daniel Eischen <deischen@freebsd.org>. 3 * Copyright (c) 2005 David Xu <davidxu@freebsd.org>. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD: head/lib/libthr/arch/i386/include/pthread_md.h 145578 2005-04-27 01:29:03Z davidxu $ 28 */ 29 30/* 31 * Machine-dependent thread prototypes/definitions. 32 */ 33#ifndef _PTHREAD_MD_H_ 34#define _PTHREAD_MD_H_ 35 36#include <stddef.h> 37#include <sys/types.h> 38#include <machine/sysarch.h> 39 40#define DTV_OFFSET offsetof(struct tcb, tcb_dtv) 41 42extern int _thr_using_setbase; 43 44/* 45 * Variant II tcb, first two members are required by rtld, 46 * %gs points to the structure. 47 */ 48struct tcb { 49 struct tcb *tcb_self; /* required by rtld */ 50 void *tcb_dtv; /* required by rtld */ 51 struct pthread *tcb_thread; 52}; 53 54/* 55 * Evaluates to the byte offset of the per-tcb variable name. 56 */ 57#define __tcb_offset(name) __offsetof(struct tcb, name) 58 59/* 60 * Evaluates to the type of the per-tcb variable name. 61 */ 62#define __tcb_type(name) __typeof(((struct tcb *)0)->name) 63 64/* 65 * Evaluates to the value of the per-tcb variable name. 66 */ 67#define TCB_GET32(name) ({ \ 68 __tcb_type(name) __result; \ 69 \ 70 u_int __i; \ 71 __asm __volatile("movl %%gs:%1, %0" \ 72 : "=r" (__i) \ 73 : "m" (*(u_int *)(__tcb_offset(name)))); \ 74 __result = (__tcb_type(name))__i; \ 75 \ 76 __result; \ 77}) 78 79/* 80 * The constructors. 81 */ 82struct tcb *_tcb_ctor(struct pthread *, int); 83void _tcb_dtor(struct tcb *tcb); 84 85/* Called from the thread to set its private data. */ 86static __inline void 87_tcb_set(struct tcb *tcb) 88{ 89 i386_set_gsbase(tcb); 90} 91 92/* Get the current kcb. */ 93static __inline struct tcb * 94_tcb_get(void) 95{ 96 return (TCB_GET32(tcb_self)); 97} 98 99extern struct pthread *_thr_initial; 100 101/* Get the current thread. */ 102static __inline struct pthread * 103_get_curthread(void) 104{ 105 if (_thr_initial) 106 return (TCB_GET32(tcb_thread)); 107 return (NULL); 108} 109#endif 110