pthread_md.h revision 118510 
1/*-
2 * Copyright (c) 2002 Daniel Eischen <deischen@freebsd.org>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/lib/libkse/arch/i386/include/pthread_md.h 118510 2003-08-05 22:46:00Z deischen $
27 */
28/*
29 * Machine-dependent thread prototypes/definitions for the thread kernel.
30 */
31#ifndef _PTHREAD_MD_H_
32#define	_PTHREAD_MD_H_
33
34#include <sys/kse.h>
35#include <ucontext.h>
36
37extern int _thr_setcontext(mcontext_t *, intptr_t, intptr_t *);
38extern int _thr_getcontext(mcontext_t *);
39
40#define	THR_GETCONTEXT(ucp)	_thr_getcontext(&(ucp)->uc_mcontext)
41#define	THR_SETCONTEXT(ucp)	_thr_setcontext(&(ucp)->uc_mcontext, 0, NULL)
42
43#define	PER_KSE
44#undef	PER_THREAD
45
46struct kse;
47struct pthread;
48struct tdv;
49
50/*
51 * %gs points to a struct kcb.
52 */
53struct kcb {
54	struct tcb		*kcb_curtcb;
55	struct kcb		*kcb_self;	/* self reference */
56	int			kcb_ldt;
57	struct kse		*kcb_kse;
58	struct kse_mailbox	kcb_kmbx;
59};
60
61struct tcb {
62	struct tdv		*tcb_tdv;
63	struct pthread		*tcb_thread;
64	void			*tcb_addr;	/* allocated tcb address */
65	void			*tcb_spare;	/* align tcb_tmbx to 16 bytes */
66	struct kse_thr_mailbox	tcb_tmbx;
67};
68
69/*
70 * Evaluates to the byte offset of the per-kse variable name.
71 */
72#define	__kcb_offset(name)	__offsetof(struct kcb, name)
73
74/*
75 * Evaluates to the type of the per-kse variable name.
76 */
77#define	__kcb_type(name)	__typeof(((struct kcb *)0)->name)
78
79/*
80 * Evaluates to the value of the per-kse variable name.
81 */
82#define	KCB_GET32(name) ({					\
83	__kcb_type(name) __result;				\
84								\
85	u_int __i;						\
86	__asm __volatile("movl %%gs:%1, %0"			\
87	    : "=r" (__i)					\
88	    : "m" (*(u_int *)(__kcb_offset(name))));		\
89	__result = *(__kcb_type(name) *)&__i;			\
90								\
91	__result;						\
92})
93
94/*
95 * Sets the value of the per-kse variable name to value val.
96 */
97#define	KCB_SET32(name, val) ({					\
98	__kcb_type(name) __val = (val);				\
99								\
100	u_int __i;						\
101	__i = *(u_int *)&__val;					\
102	__asm __volatile("movl %1,%%gs:%0"			\
103	    : "=m" (*(u_int *)(__kcb_offset(name)))		\
104	    : "r" (__i));					\
105})
106
107static __inline u_long
108__kcb_readandclear32(volatile u_long *addr)
109{
110	u_long result;
111
112	__asm __volatile (
113	    "	xorl	%0, %0;"
114	    "	xchgl	%%gs:%1, %0;"
115	    "# __kcb_readandclear32"
116	    : "=&r" (result)
117	    : "m" (*addr));
118	return (result);
119}
120
121#define	KCB_READANDCLEAR32(name) ({				\
122	__kcb_type(name) __result;				\
123								\
124	__result = (__kcb_type(name))				\
125	    __kcb_readandclear32((u_long *)__kcb_offset(name)); \
126	__result;						\
127})
128
129
130#define	_kcb_curkcb()		KCB_GET32(kcb_self)
131#define	_kcb_curtcb()		KCB_GET32(kcb_curtcb)
132#define	_kcb_curkse()		((struct kse *)KCB_GET32(kcb_kmbx.km_udata))
133#define	_kcb_get_tmbx()		KCB_GET32(kcb_kmbx.km_curthread)
134#define	_kcb_set_tmbx(value)	KCB_SET32(kcb_kmbx.km_curthread, (void *)value)
135#define	_kcb_readandclear_tmbx() KCB_READANDCLEAR32(kcb_kmbx.km_curthread)
136
137
138/*
139 * The constructors.
140 */
141struct tcb	*_tcb_ctor(struct pthread *);
142void		_tcb_dtor(struct tcb *tcb);
143struct kcb	*_kcb_ctor(struct kse *);
144void		_kcb_dtor(struct kcb *);
145
146/* Called from the KSE to set its private data. */
147static __inline void
148_kcb_set(struct kcb *kcb)
149{
150	int val;
151
152	val = (kcb->kcb_ldt << 3) | 7;
153	__asm __volatile("movl %0, %%gs" : : "r" (val));
154}
155
156/* Get the current kcb. */
157static __inline struct kcb *
158_kcb_get(void)
159{
160	return (_kcb_curkcb());
161}
162
163static __inline struct kse_thr_mailbox *
164_kcb_critical_enter(void)
165{
166	struct kse_thr_mailbox *crit;
167
168	crit = _kcb_readandclear_tmbx();
169	return (crit);
170}
171
172static __inline void
173_kcb_critical_leave(struct kse_thr_mailbox *crit)
174{
175	_kcb_set_tmbx(crit);
176}
177
178static __inline int
179_kcb_in_critical(void)
180{
181	return (_kcb_get_tmbx() == NULL);
182}
183
184static __inline void
185_tcb_set(struct kcb *kcb, struct tcb *tcb)
186{
187	kcb->kcb_curtcb = tcb;
188}
189
190static __inline struct tcb *
191_tcb_get(void)
192{
193	return (_kcb_curtcb());
194}
195
196static __inline struct pthread *
197_get_curthread(void)
198{
199	struct tcb *tcb;
200
201	tcb = _kcb_curtcb();
202	if (tcb != NULL)
203		return (tcb->tcb_thread);
204	else
205		return (NULL);
206}
207
208static __inline struct kse *
209_get_curkse(void)
210{
211	return ((struct kse *)_kcb_curkse());
212}
213
214void	_i386_enter_uts(struct kse_mailbox *km, kse_func_t uts, void *stack,
215    size_t stacksz);
216
217static __inline int
218_thread_enter_uts(struct tcb *tcb, struct kcb *kcb)
219{
220	int ret;
221
222	ret = _thr_getcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext);
223	if (ret == 0) {
224		_i386_enter_uts(&kcb->kcb_kmbx, kcb->kcb_kmbx.km_func,
225		    kcb->kcb_kmbx.km_stack.ss_sp,
226		    kcb->kcb_kmbx.km_stack.ss_size);
227		/* We should not reach here. */
228		return (-1);
229	}
230	else if (ret < 0)
231		return (-1);
232	return (0);
233}
234
235static __inline int
236_thread_switch(struct kcb *kcb, struct tcb *tcb, int setmbox)
237{
238	if ((kcb == NULL) || (tcb == NULL))
239		return (-1);
240	kcb->kcb_curtcb = tcb;
241	if (setmbox != 0)
242		_thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext,
243		    (intptr_t)&tcb->tcb_tmbx,
244		    (intptr_t *)&kcb->kcb_kmbx.km_curthread);
245	else
246		_thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext, 0, NULL);
247	/* We should not reach here. */
248	return (-1);
249}
250
251#endif
252