pthread_md.h revision 144518 
1/*-
2 * Copyright (C) 2003 David Xu <davidxu@freebsd.org>
3 * Copyright (c) 2001 Daniel Eischen <deischen@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. Neither the name of the author nor the names of its contributors
12 *    may be used to endorse or promote products derived from this software
13 *    without specific prior written permission.
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/amd64/include/pthread_md.h 144518 2005-04-02 01:20:00Z 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#include <ucontext.h>
40
41#define	DTV_OFFSET		offsetof(struct tcb, tcb_dtv)
42
43/*
44 * Variant II tcb, first two members are required by rtld,
45 * %fs points to the structure.
46 */
47struct tcb {
48	struct tcb		*tcb_self;	/* required by rtld */
49	void			*tcb_dtv;	/* required by rtld */
50	struct pthread		*tcb_thread;
51	void			*tcb_spare[1];
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_GET64(name) ({					\
68	__tcb_type(name) __result;				\
69								\
70	u_long __i;						\
71	__asm __volatile("movq %%fs:%1, %0"			\
72	    : "=r" (__i)					\
73	    : "m" (*(u_long *)(__tcb_offset(name))));		\
74	__result = (__tcb_type(name))__i;			\
75								\
76	__result;						\
77})
78
79struct tcb	*_tcb_ctor(struct pthread *, int);
80void		_tcb_dtor(struct tcb *tcb);
81
82static __inline void
83_tcb_set(struct tcb *tcb)
84{
85	amd64_set_fsbase(tcb);
86}
87
88static __inline struct tcb *
89_tcb_get(void)
90{
91	return (TCB_GET64(tcb_self));
92}
93
94extern struct pthread *_thr_initial;
95
96static __inline struct pthread *
97_get_curthread(void)
98{
99	if (_thr_initial)
100		return (TCB_GET64(tcb_thread));
101	return (NULL);
102}
103#endif
104