lib/libkse/arch/i386/include/pthread_md.h

   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  * $FreeBSD$
  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
  40 extern int _thr_setcontext(mcontext_t *, intptr_t, intptr_t *);
  41 extern 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
  52 struct kse;
  53 struct pthread;
  54
  55 /*
  56  * %gs points to a struct kcb.
  57  */
  58 struct kcb {
  59         struct tcb              *kcb_curtcb;
  60         struct kcb              *kcb_self;      /* self reference */
  61         struct kse              *kcb_kse;
  62         struct kse_mailbox      kcb_kmbx;
  63 };
  64
  65 struct tcb {
  66         struct tcb              *tcb_self;      /* required by rtld */
  67         void                    *tcb_dtv;       /* required by rtld */
  68         struct pthread          *tcb_thread;
  69         void                    *tcb_spare;     /* align tcb_tmbx to 16 bytes */
  70         struct kse_thr_mailbox  tcb_tmbx;
  71 };
  72
  73 /*
  74  * Evaluates to the byte offset of the per-kse variable name.
  75  */
  76 #define __kcb_offset(name)      __offsetof(struct kcb, name)
  77
  78 /*
  79  * Evaluates to the type of the per-kse variable name.
  80  */
  81 #define __kcb_type(name)        __typeof(((struct kcb *)0)->name)
  82
  83 /*
  84  * Evaluates to the value of the per-kse variable name.
  85  */
  86 #define KCB_GET32(name) ({                                      \
  87         __kcb_type(name) __result;                              \
  88                                                                 \
  89         u_int __i;                                              \
  90         __asm __volatile("movl %%gs:%1, %0"                     \
  91             : "=r" (__i)                                        \
  92             : "m" (*(u_int *)(__kcb_offset(name))));            \
  93         __result = (__kcb_type(name))__i;                       \
  94                                                                 \
  95         __result;                                               \
  96 })
  97
  98 /*
  99  * Sets the value of the per-kse variable name to value val.
 100  */
 101 #define KCB_SET32(name, val) ({                                 \
 102         __kcb_type(name) __val = (val);                         \
 103                                                                 \
 104         u_int __i;                                              \
 105         __i = (u_int)__val;                                     \
 106         __asm __volatile("movl %1,%%gs:%0"                      \
 107             : "=m" (*(u_int *)(__kcb_offset(name)))             \
 108             : "r" (__i));                                       \
 109 })
 110
 111 static __inline u_long
 112 __kcb_readandclear32(volatile u_long *addr)
 113 {
 114         u_long result;
 115
 116         __asm __volatile (
 117             "   xorl    %0, %0;"
 118             "   xchgl   %%gs:%1, %0;"
 119             "# __kcb_readandclear32"
 120             : "=&r" (result)
 121             : "m" (*addr));
 122         return (result);
 123 }
 124
 125 #define KCB_READANDCLEAR32(name) ({                             \
 126         __kcb_type(name) __result;                              \
 127                                                                 \
 128         __result = (__kcb_type(name))                           \
 129             __kcb_readandclear32((u_long *)__kcb_offset(name)); \
 130         __result;                                               \
 131 })
 132
 133
 134 #define _kcb_curkcb()           KCB_GET32(kcb_self)
 135 #define _kcb_curtcb()           KCB_GET32(kcb_curtcb)
 136 #define _kcb_curkse()           ((struct kse *)KCB_GET32(kcb_kmbx.km_udata))
 137 #define _kcb_get_tmbx()         KCB_GET32(kcb_kmbx.km_curthread)
 138 #define _kcb_set_tmbx(value)    KCB_SET32(kcb_kmbx.km_curthread, (void *)value)
 139 #define _kcb_readandclear_tmbx() KCB_READANDCLEAR32(kcb_kmbx.km_curthread)
 140
 141
 142 /*
 143  * The constructors.
 144  */
 145 struct tcb      *_tcb_ctor(struct pthread *, int);
 146 void            _tcb_dtor(struct tcb *tcb);
 147 struct kcb      *_kcb_ctor(struct kse *);
 148 void            _kcb_dtor(struct kcb *);
 149
 150 /* Called from the KSE to set its private data. */
 151 static __inline void
 152 _kcb_set(struct kcb *kcb)
 153 {
 154         i386_set_gsbase(kcb);
 155 }
 156
 157 /* Get the current kcb. */
 158 static __inline struct kcb *
 159 _kcb_get(void)
 160 {
 161         return (_kcb_curkcb());
 162 }
 163
 164 static __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
 173 static __inline void
 174 _kcb_critical_leave(struct kse_thr_mailbox *crit)
 175 {
 176         _kcb_set_tmbx(crit);
 177 }
 178
 179 static __inline int
 180 _kcb_in_critical(void)
 181 {
 182         return (_kcb_get_tmbx() == NULL);
 183 }
 184
 185 static __inline void
 186 _tcb_set(struct kcb *kcb, struct tcb *tcb)
 187 {
 188         kcb->kcb_curtcb = tcb;
 189 }
 190
 191 static __inline struct tcb *
 192 _tcb_get(void)
 193 {
 194         return (_kcb_curtcb());
 195 }
 196
 197 static __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
 209 static __inline struct kse *
 210 _get_curkse(void)
 211 {
 212         return ((struct kse *)_kcb_curkse());
 213 }
 214
 215 void    _i386_enter_uts(struct kse_mailbox *km, kse_func_t uts, void *stack,
 216     size_t stacksz);
 217
 218 static __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
 236 static __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 *)(void *)&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