pthread_md.h revision 145569 
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 145569 2005-04-26 20:41:48Z 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
43extern int _thr_using_setbase;
44
45#define	KSE_STACKSIZE		16384
46#define	DTV_OFFSET		offsetof(struct tcb, tcb_dtv)
47
48#define	THR_GETCONTEXT(ucp)	_thr_getcontext(&(ucp)->uc_mcontext)
49#define	THR_SETCONTEXT(ucp)	_thr_setcontext(&(ucp)->uc_mcontext, 0, NULL)
50
51#define	PER_KSE
52#undef	PER_THREAD
53
54struct kse;
55struct pthread;
56
57/*
58 * %gs points to a struct kcb.
59 */
60struct kcb {
61	struct tcb		*kcb_curtcb;
62	struct kcb		*kcb_self;	/* self reference */
63	int			kcb_ldt;
64	struct kse		*kcb_kse;
65	struct kse_mailbox	kcb_kmbx;
66};
67
68struct tcb {
69	struct tcb		*tcb_self;	/* required by rtld */
70	void			*tcb_dtv;	/* required by rtld */
71	struct pthread		*tcb_thread;
72	void			*tcb_spare;	/* align tcb_tmbx to 16 bytes */
73	struct kse_thr_mailbox	tcb_tmbx;
74};
75
76/*
77 * Evaluates to the byte offset of the per-kse variable name.
78 */
79#define	__kcb_offset(name)	__offsetof(struct kcb, name)
80
81/*
82 * Evaluates to the type of the per-kse variable name.
83 */
84#define	__kcb_type(name)	__typeof(((struct kcb *)0)->name)
85
86/*
87 * Evaluates to the value of the per-kse variable name.
88 */
89#define	KCB_GET32(name) ({					\
90	__kcb_type(name) __result;				\
91								\
92	u_int __i;						\
93	__asm __volatile("movl %%gs:%1, %0"			\
94	    : "=r" (__i)					\
95	    : "m" (*(u_int *)(__kcb_offset(name))));		\
96	__result = (__kcb_type(name))__i;			\
97								\
98	__result;						\
99})
100
101/*
102 * Sets the value of the per-kse variable name to value val.
103 */
104#define	KCB_SET32(name, val) ({					\
105	__kcb_type(name) __val = (val);				\
106								\
107	u_int __i;						\
108	__i = (u_int)__val;					\
109	__asm __volatile("movl %1,%%gs:%0"			\
110	    : "=m" (*(u_int *)(__kcb_offset(name)))		\
111	    : "r" (__i));					\
112})
113
114static __inline u_long
115__kcb_readandclear32(volatile u_long *addr)
116{
117	u_long result;
118
119	__asm __volatile (
120	    "	xorl	%0, %0;"
121	    "	xchgl	%%gs:%1, %0;"
122	    "# __kcb_readandclear32"
123	    : "=&r" (result)
124	    : "m" (*addr));
125	return (result);
126}
127
128#define	KCB_READANDCLEAR32(name) ({				\
129	__kcb_type(name) __result;				\
130								\
131	__result = (__kcb_type(name))				\
132	    __kcb_readandclear32((u_long *)__kcb_offset(name)); \
133	__result;						\
134})
135
136
137#define	_kcb_curkcb()		KCB_GET32(kcb_self)
138#define	_kcb_curtcb()		KCB_GET32(kcb_curtcb)
139#define	_kcb_curkse()		((struct kse *)KCB_GET32(kcb_kmbx.km_udata))
140#define	_kcb_get_tmbx()		KCB_GET32(kcb_kmbx.km_curthread)
141#define	_kcb_set_tmbx(value)	KCB_SET32(kcb_kmbx.km_curthread, (void *)value)
142#define	_kcb_readandclear_tmbx() KCB_READANDCLEAR32(kcb_kmbx.km_curthread)
143
144
145/*
146 * The constructors.
147 */
148struct tcb	*_tcb_ctor(struct pthread *, int);
149void		_tcb_dtor(struct tcb *tcb);
150struct kcb	*_kcb_ctor(struct kse *);
151void		_kcb_dtor(struct kcb *);
152
153/* Called from the KSE to set its private data. */
154static __inline void
155_kcb_set(struct kcb *kcb)
156{
157	int val;
158
159	if (_thr_using_setbase == 1) {
160		i386_set_gsbase(kcb);
161	} else {
162		val = (kcb->kcb_ldt << 3) | 7;
163		__asm __volatile("movl %0, %%gs" : : "r" (val));
164	}
165
166}
167
168/* Get the current kcb. */
169static __inline struct kcb *
170_kcb_get(void)
171{
172	return (_kcb_curkcb());
173}
174
175static __inline struct kse_thr_mailbox *
176_kcb_critical_enter(void)
177{
178	struct kse_thr_mailbox *crit;
179
180	crit = _kcb_readandclear_tmbx();
181	return (crit);
182}
183
184static __inline void
185_kcb_critical_leave(struct kse_thr_mailbox *crit)
186{
187	_kcb_set_tmbx(crit);
188}
189
190static __inline int
191_kcb_in_critical(void)
192{
193	return (_kcb_get_tmbx() == NULL);
194}
195
196static __inline void
197_tcb_set(struct kcb *kcb, struct tcb *tcb)
198{
199	kcb->kcb_curtcb = tcb;
200}
201
202static __inline struct tcb *
203_tcb_get(void)
204{
205	return (_kcb_curtcb());
206}
207
208static __inline struct pthread *
209_get_curthread(void)
210{
211	struct tcb *tcb;
212
213	tcb = _kcb_curtcb();
214	if (tcb != NULL)
215		return (tcb->tcb_thread);
216	else
217		return (NULL);
218}
219
220static __inline struct kse *
221_get_curkse(void)
222{
223	return ((struct kse *)_kcb_curkse());
224}
225
226void	_i386_enter_uts(struct kse_mailbox *km, kse_func_t uts, void *stack,
227    size_t stacksz);
228
229static __inline int
230_thread_enter_uts(struct tcb *tcb, struct kcb *kcb)
231{
232	int ret;
233
234	ret = _thr_getcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext);
235	if (ret == 0) {
236		_i386_enter_uts(&kcb->kcb_kmbx, kcb->kcb_kmbx.km_func,
237		    kcb->kcb_kmbx.km_stack.ss_sp,
238		    kcb->kcb_kmbx.km_stack.ss_size);
239		/* We should not reach here. */
240		return (-1);
241	}
242	else if (ret < 0)
243		return (-1);
244	return (0);
245}
246
247static __inline int
248_thread_switch(struct kcb *kcb, struct tcb *tcb, int setmbox)
249{
250	extern int _libkse_debug;
251
252	if ((kcb == NULL) || (tcb == NULL))
253		return (-1);
254	kcb->kcb_curtcb = tcb;
255	if (_libkse_debug == 0) {
256		tcb->tcb_tmbx.tm_lwp = kcb->kcb_kmbx.km_lwp;
257		if (setmbox != 0)
258			_thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext,
259			    (intptr_t)&tcb->tcb_tmbx,
260			    (intptr_t *)&kcb->kcb_kmbx.km_curthread);
261		else
262			_thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext,
263				0, NULL);
264	} else {
265		if (setmbox)
266			kse_switchin(&tcb->tcb_tmbx, KSE_SWITCHIN_SETTMBX);
267		else
268			kse_switchin(&tcb->tcb_tmbx, 0);
269	}
270
271	/* We should not reach here. */
272	return (-1);
273}
274
275#endif
276