pthread_md.h revision 137295 
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 137295 2004-11-06 03:35:51Z peter $
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 <stddef.h>
35#include <sys/types.h>
36#include <sys/kse.h>
37#include <machine/sysarch.h>
38#include <ucontext.h>
39
40extern int _thr_setcontext(mcontext_t *, intptr_t, intptr_t *);
41extern int _thr_getcontext(mcontext_t *);
42
43#define	KSE_STACKSIZE		16384
44#define	DTV_OFFSET		offsetof(struct tcb, tcb_dtv)
45
46#define	THR_GETCONTEXT(ucp)	_thr_getcontext(&(ucp)->uc_mcontext)
47#define	THR_SETCONTEXT(ucp)	_thr_setcontext(&(ucp)->uc_mcontext, 0, NULL)
48
49#define	PER_KSE
50#undef	PER_THREAD
51
52struct kse;
53struct pthread;
54
55/*
56 * %gs points to a struct kcb.
57 */
58struct kcb {
59	struct tcb		*kcb_curtcb;
60	struct kcb		*kcb_self;	/* self reference */
61	int			kcb_ldt;
62	struct kse		*kcb_kse;
63	struct kse_mailbox	kcb_kmbx;
64};
65
66struct tcb {
67	struct tcb		*tcb_self;	/* required by rtld */
68	void			*tcb_dtv;	/* required by rtld */
69	struct pthread		*tcb_thread;
70	void			*tcb_spare;	/* align tcb_tmbx to 16 bytes */
71	struct kse_thr_mailbox	tcb_tmbx;
72};
73
74/*
75 * Evaluates to the byte offset of the per-kse variable name.
76 */
77#define	__kcb_offset(name)	__offsetof(struct kcb, name)
78
79/*
80 * Evaluates to the type of the per-kse variable name.
81 */
82#define	__kcb_type(name)	__typeof(((struct kcb *)0)->name)
83
84/*
85 * Evaluates to the value of the per-kse variable name.
86 */
87#define	KCB_GET32(name) ({					\
88	__kcb_type(name) __result;				\
89								\
90	u_int __i;						\
91	__asm __volatile("movl %%gs:%1, %0"			\
92	    : "=r" (__i)					\
93	    : "m" (*(u_int *)(__kcb_offset(name))));		\
94	__result = (__kcb_type(name))__i;			\
95								\
96	__result;						\
97})
98
99/*
100 * Sets the value of the per-kse variable name to value val.
101 */
102#define	KCB_SET32(name, val) ({					\
103	__kcb_type(name) __val = (val);				\
104								\
105	u_int __i;						\
106	__i = (u_int)__val;					\
107	__asm __volatile("movl %1,%%gs:%0"			\
108	    : "=m" (*(u_int *)(__kcb_offset(name)))		\
109	    : "r" (__i));					\
110})
111
112static __inline u_long
113__kcb_readandclear32(volatile u_long *addr)
114{
115	u_long result;
116
117	__asm __volatile (
118	    "	xorl	%0, %0;"
119	    "	xchgl	%%gs:%1, %0;"
120	    "# __kcb_readandclear32"
121	    : "=&r" (result)
122	    : "m" (*addr));
123	return (result);
124}
125
126#define	KCB_READANDCLEAR32(name) ({				\
127	__kcb_type(name) __result;				\
128								\
129	__result = (__kcb_type(name))				\
130	    __kcb_readandclear32((u_long *)__kcb_offset(name)); \
131	__result;						\
132})
133
134
135#define	_kcb_curkcb()		KCB_GET32(kcb_self)
136#define	_kcb_curtcb()		KCB_GET32(kcb_curtcb)
137#define	_kcb_curkse()		((struct kse *)KCB_GET32(kcb_kmbx.km_udata))
138#define	_kcb_get_tmbx()		KCB_GET32(kcb_kmbx.km_curthread)
139#define	_kcb_set_tmbx(value)	KCB_SET32(kcb_kmbx.km_curthread, (void *)value)
140#define	_kcb_readandclear_tmbx() KCB_READANDCLEAR32(kcb_kmbx.km_curthread)
141
142
143/*
144 * The constructors.
145 */
146struct tcb	*_tcb_ctor(struct pthread *, int);
147void		_tcb_dtor(struct tcb *tcb);
148struct kcb	*_kcb_ctor(struct kse *);
149void		_kcb_dtor(struct kcb *);
150
151/* Called from the KSE to set its private data. */
152static __inline void
153_kcb_set(struct kcb *kcb)
154{
155#ifndef COMPAT_32BIT
156	int val;
157
158	val = (kcb->kcb_ldt << 3) | 7;
159	__asm __volatile("movl %0, %%gs" : : "r" (val));
160#else
161	_amd64_set_gsbase(kcb);
162#endif
163
164}
165
166/* Get the current kcb. */
167static __inline struct kcb *
168_kcb_get(void)
169{
170	return (_kcb_curkcb());
171}
172
173static __inline struct kse_thr_mailbox *
174_kcb_critical_enter(void)
175{
176	struct kse_thr_mailbox *crit;
177
178	crit = _kcb_readandclear_tmbx();
179	return (crit);
180}
181
182static __inline void
183_kcb_critical_leave(struct kse_thr_mailbox *crit)
184{
185	_kcb_set_tmbx(crit);
186}
187
188static __inline int
189_kcb_in_critical(void)
190{
191	return (_kcb_get_tmbx() == NULL);
192}
193
194static __inline void
195_tcb_set(struct kcb *kcb, struct tcb *tcb)
196{
197	kcb->kcb_curtcb = tcb;
198}
199
200static __inline struct tcb *
201_tcb_get(void)
202{
203	return (_kcb_curtcb());
204}
205
206static __inline struct pthread *
207_get_curthread(void)
208{
209	struct tcb *tcb;
210
211	tcb = _kcb_curtcb();
212	if (tcb != NULL)
213		return (tcb->tcb_thread);
214	else
215		return (NULL);
216}
217
218static __inline struct kse *
219_get_curkse(void)
220{
221	return ((struct kse *)_kcb_curkse());
222}
223
224void	_i386_enter_uts(struct kse_mailbox *km, kse_func_t uts, void *stack,
225    size_t stacksz);
226
227static __inline int
228_thread_enter_uts(struct tcb *tcb, struct kcb *kcb)
229{
230	int ret;
231
232	ret = _thr_getcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext);
233	if (ret == 0) {
234		_i386_enter_uts(&kcb->kcb_kmbx, kcb->kcb_kmbx.km_func,
235		    kcb->kcb_kmbx.km_stack.ss_sp,
236		    kcb->kcb_kmbx.km_stack.ss_size);
237		/* We should not reach here. */
238		return (-1);
239	}
240	else if (ret < 0)
241		return (-1);
242	return (0);
243}
244
245static __inline int
246_thread_switch(struct kcb *kcb, struct tcb *tcb, int setmbox)
247{
248	extern int _libkse_debug;
249
250	if ((kcb == NULL) || (tcb == NULL))
251		return (-1);
252	kcb->kcb_curtcb = tcb;
253	if (_libkse_debug == 0) {
254		tcb->tcb_tmbx.tm_lwp = kcb->kcb_kmbx.km_lwp;
255		if (setmbox != 0)
256			_thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext,
257			    (intptr_t)&tcb->tcb_tmbx,
258			    (intptr_t *)&kcb->kcb_kmbx.km_curthread);
259		else
260			_thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext,
261				0, NULL);
262	} else {
263		if (setmbox)
264			kse_switchin(&tcb->tcb_tmbx, KSE_SWITCHIN_SETTMBX);
265		else
266			kse_switchin(&tcb->tcb_tmbx, 0);
267	}
268
269	/* We should not reach here. */
270	return (-1);
271}
272
273#endif
274