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 133756 2004-08-15 16:28:05Z dfr $
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 KSE_STACKSIZE 16384
41
42#define THR_GETCONTEXT(ucp) _thr_getcontext(&(ucp)->uc_mcontext)
43#define THR_SETCONTEXT(ucp) _thr_setcontext(&(ucp)->uc_mcontext, 0, NULL)
44
45#define PER_KSE
46#undef PER_THREAD
47
48struct kse;
49struct pthread;
50
51/*
52 * %gs points to a struct kcb.
53 */
54struct kcb {
55 struct tcb *kcb_curtcb;
56 struct kcb *kcb_self; /* self reference */
57 int kcb_ldt;
58 struct kse *kcb_kse;
59 struct kse_mailbox kcb_kmbx;
60};
61
62struct tcb {
63 struct tcb *tcb_self; /* required by rtld */
64 void *tcb_dtv; /* required by rtld */
65 struct pthread *tcb_thread;
66 void *tcb_spare; /* align tcb_tmbx to 16 bytes */
67 struct kse_thr_mailbox tcb_tmbx;
68};
69
70/*
71 * Evaluates to the byte offset of the per-kse variable name.
72 */
73#define __kcb_offset(name) __offsetof(struct kcb, name)
74
75/*
76 * Evaluates to the type of the per-kse variable name.
77 */
78#define __kcb_type(name) __typeof(((struct kcb *)0)->name)
79
80/*
81 * Evaluates to the value of the per-kse variable name.
82 */
83#define KCB_GET32(name) ({ \
84 __kcb_type(name) __result; \
85 \
86 u_int __i; \
87 __asm __volatile("movl %%gs:%1, %0" \
88 : "=r" (__i) \
89 : "m" (*(u_int *)(__kcb_offset(name)))); \
90 __result = *(__kcb_type(name) *)&__i; \
91 \
92 __result; \
93})
94
95/*
96 * Sets the value of the per-kse variable name to value val.
97 */
98#define KCB_SET32(name, val) ({ \
99 __kcb_type(name) __val = (val); \
100 \
101 u_int __i; \
102 __i = *(u_int *)&__val; \
103 __asm __volatile("movl %1,%%gs:%0" \
104 : "=m" (*(u_int *)(__kcb_offset(name))) \
105 : "r" (__i)); \
106})
107
108static __inline u_long
109__kcb_readandclear32(volatile u_long *addr)
110{
111 u_long result;
112
113 __asm __volatile (
114 " xorl %0, %0;"
115 " xchgl %%gs:%1, %0;"
116 "# __kcb_readandclear32"
117 : "=&r" (result)
118 : "m" (*addr));
119 return (result);
120}
121
122#define KCB_READANDCLEAR32(name) ({ \
123 __kcb_type(name) __result; \
124 \
125 __result = (__kcb_type(name)) \
126 __kcb_readandclear32((u_long *)__kcb_offset(name)); \
127 __result; \
128})
129
130
131#define _kcb_curkcb() KCB_GET32(kcb_self)
132#define _kcb_curtcb() KCB_GET32(kcb_curtcb)
133#define _kcb_curkse() ((struct kse *)KCB_GET32(kcb_kmbx.km_udata))
134#define _kcb_get_tmbx() KCB_GET32(kcb_kmbx.km_curthread)
135#define _kcb_set_tmbx(value) KCB_SET32(kcb_kmbx.km_curthread, (void *)value)
136#define _kcb_readandclear_tmbx() KCB_READANDCLEAR32(kcb_kmbx.km_curthread)
137
138
139/*
140 * The constructors.
141 */
142struct tcb *_tcb_ctor(struct pthread *, int);
143void _tcb_dtor(struct tcb *tcb);
144struct kcb *_kcb_ctor(struct kse *);
145void _kcb_dtor(struct kcb *);
146
147/* Called from the KSE to set its private data. */
148static __inline void
149_kcb_set(struct kcb *kcb)
150{
151 int val;
152
153 val = (kcb->kcb_ldt << 3) | 7;
154 __asm __volatile("movl %0, %%gs" : : "r" (val));
155}
156
157/* Get the current kcb. */
158static __inline struct kcb *
159_kcb_get(void)
160{
161 return (_kcb_curkcb());
162}
163
164static __inline struct kse_thr_mailbox *
165_kcb_critical_enter(void)
166{
167 struct kse_thr_mailbox *crit;
168
169 crit = _kcb_readandclear_tmbx();
170 return (crit);
171}
172
173static __inline void
174_kcb_critical_leave(struct kse_thr_mailbox *crit)
175{
176 _kcb_set_tmbx(crit);
177}
178
179static __inline int
180_kcb_in_critical(void)
181{
182 return (_kcb_get_tmbx() == NULL);
183}
184
185static __inline void
186_tcb_set(struct kcb *kcb, struct tcb *tcb)
187{
188 kcb->kcb_curtcb = tcb;
189}
190
191static __inline struct tcb *
192_tcb_get(void)
193{
194 return (_kcb_curtcb());
195}
196
197static __inline struct pthread *
198_get_curthread(void)
199{
200 struct tcb *tcb;
201
202 tcb = _kcb_curtcb();
203 if (tcb != NULL)
204 return (tcb->tcb_thread);
205 else
206 return (NULL);
207}
208
209static __inline struct kse *
210_get_curkse(void)
211{
212 return ((struct kse *)_kcb_curkse());
213}
214
215void _i386_enter_uts(struct kse_mailbox *km, kse_func_t uts, void *stack,
216 size_t stacksz);
217
218static __inline int
219_thread_enter_uts(struct tcb *tcb, struct kcb *kcb)
220{
221 int ret;
222
223 ret = _thr_getcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext);
224 if (ret == 0) {
225 _i386_enter_uts(&kcb->kcb_kmbx, kcb->kcb_kmbx.km_func,
226 kcb->kcb_kmbx.km_stack.ss_sp,
227 kcb->kcb_kmbx.km_stack.ss_size);
228 /* We should not reach here. */
229 return (-1);
230 }
231 else if (ret < 0)
232 return (-1);
233 return (0);
234}
235
236static __inline int
237_thread_switch(struct kcb *kcb, struct tcb *tcb, int setmbox)
238{
239 extern int _libkse_debug;
240
241 if ((kcb == NULL) || (tcb == NULL))
242 return (-1);
243 kcb->kcb_curtcb = tcb;
244 if (_libkse_debug == 0) {
245 tcb->tcb_tmbx.tm_lwp = kcb->kcb_kmbx.km_lwp;
246 if (setmbox != 0)
247 _thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext,
248 (intptr_t)&tcb->tcb_tmbx,
249 (intptr_t *)&kcb->kcb_kmbx.km_curthread);
250 else
251 _thr_setcontext(&tcb->tcb_tmbx.tm_context.uc_mcontext,
252 0, NULL);
253 } else {
254 if (setmbox)
255 kse_switchin(&tcb->tcb_tmbx, KSE_SWITCHIN_SETTMBX);
256 else
257 kse_switchin(&tcb->tcb_tmbx, 0);
258 }
259
260 /* We should not reach here. */
261 return (-1);
262}
263
264#endif