xref: /freebsd/lib/libthr/arch/amd64/include/pthread_md.h (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (C) 2003 David Xu <davidxu@freebsd.org>
5  * Copyright (c) 2001 Daniel Eischen <deischen@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. Neither the name of the author nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
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  * %fs 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 	void			*tcb_spare[1];
55 };
56 
57 /*
58  * Evaluates to the byte offset of the per-tcb variable name.
59  */
60 #define	__tcb_offset(name)	__offsetof(struct tcb, name)
61 
62 /*
63  * Evaluates to the type of the per-tcb variable name.
64  */
65 #define	__tcb_type(name)	__typeof(((struct tcb *)0)->name)
66 
67 /*
68  * Evaluates to the value of the per-tcb variable name.
69  */
70 #define	TCB_GET64(name) ({					\
71 	__tcb_type(name) __result;				\
72 								\
73 	u_long __i;						\
74 	__asm __volatile("movq %%fs:%1, %0"			\
75 	    : "=r" (__i)					\
76 	    : "m" (*(volatile u_long *)(__tcb_offset(name))));  \
77 	__result = (__tcb_type(name))__i;			\
78 								\
79 	__result;						\
80 })
81 
82 static __inline void
83 _tcb_set(struct tcb *tcb)
84 {
85 	amd64_set_fsbase(tcb);
86 }
87 
88 static __inline struct tcb *
89 _tcb_get(void)
90 {
91 	return (TCB_GET64(tcb_self));
92 }
93 
94 static __inline struct pthread *
95 _get_curthread(void)
96 {
97 	return (TCB_GET64(tcb_thread));
98 }
99 
100 #define	HAS__UMTX_OP_ERR	1
101 
102 #endif
103