sys/i386/include/pcpu.h

   1 /*-
   2  * Copyright (c) Peter Wemm <peter@netplex.com.au>
   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 #ifndef _MACHINE_PCPU_H_
  30 #define _MACHINE_PCPU_H_
  31
  32 #ifndef _SYS_CDEFS_H_
  33 #error this file needs sys/cdefs.h as a prerequisite
  34 #endif
  35
  36 #ifdef _KERNEL
  37
  38 #include <machine/segments.h>
  39 #include <machine/tss.h>
  40
  41 /*
  42  * The SMP parts are setup in pmap.c and locore.s for the BSP, and
  43  * mp_machdep.c sets up the data for the AP's to "see" when they awake.
  44  * The reason for doing it via a struct is so that an array of pointers
  45  * to each CPU's data can be set up for things like "check curproc on all
  46  * other processors"
  47  */
  48 #define PCPU_MD_FIELDS                                                  \
  49         struct  pcpu *pc_prvspace;              /* Self-reference */    \
  50         struct  pmap *pc_curpmap;                                       \
  51         struct  i386tss pc_common_tss;                                  \
  52         struct  segment_descriptor pc_common_tssd;                      \
  53         struct  segment_descriptor *pc_tss_gdt;                         \
  54         struct  segment_descriptor *pc_fsgs_gdt;                        \
  55         int     pc_currentldt;                                          \
  56         u_int   pc_acpi_id;                                             \
  57         u_int   pc_apic_id;                                             \
  58         int     pc_private_tss  /* flag indicating private tss */
  59
  60 #if defined(lint)
  61
  62 extern struct pcpu *pcpup;
  63
  64 #define PCPU_GET(member)        (pcpup->pc_ ## member)
  65 #define PCPU_PTR(member)        (&pcpup->pc_ ## member)
  66 #define PCPU_SET(member,value)  (pcpup->pc_ ## member = (value))
  67
  68 #elif defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF) \
  69     && defined(__GNUCLIKE___OFFSETOF)
  70
  71 /*
  72  * Evaluates to the byte offset of the per-cpu variable name.
  73  */
  74 #define __pcpu_offset(name)                                             \
  75         __offsetof(struct pcpu, name)
  76
  77 /*
  78  * Evaluates to the type of the per-cpu variable name.
  79  */
  80 #define __pcpu_type(name)                                               \
  81         __typeof(((struct pcpu *)0)->name)
  82
  83 /*
  84  * Evaluates to the address of the per-cpu variable name.
  85  */
  86 #define __PCPU_PTR(name) __extension__ ({                               \
  87         __pcpu_type(name) *__p;                                         \
  88                                                                         \
  89         __asm __volatile("movl %%fs:%1,%0; addl %2,%0"                  \
  90             : "=r" (__p)                                                \
  91             : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),       \
  92               "i" (__pcpu_offset(name)));                               \
  93                                                                         \
  94         __p;                                                            \
  95 })
  96
  97 /*
  98  * Evaluates to the value of the per-cpu variable name.
  99  */
 100 #define __PCPU_GET(name) __extension__ ({                               \
 101         __pcpu_type(name) __result;                                     \
 102                                                                         \
 103         if (sizeof(__result) == 1) {                                    \
 104                 u_char __b;                                             \
 105                 __asm __volatile("movb %%fs:%1,%0"                      \
 106                     : "=r" (__b)                                        \
 107                     : "m" (*(u_char *)(__pcpu_offset(name))));          \
 108                 __result = *(__pcpu_type(name) *)(void *)&__b;          \
 109         } else if (sizeof(__result) == 2) {                             \
 110                 u_short __w;                                            \
 111                 __asm __volatile("movw %%fs:%1,%0"                      \
 112                     : "=r" (__w)                                        \
 113                     : "m" (*(u_short *)(__pcpu_offset(name))));         \
 114                 __result = *(__pcpu_type(name) *)(void *)&__w;          \
 115         } else if (sizeof(__result) == 4) {                             \
 116                 u_int __i;                                              \
 117                 __asm __volatile("movl %%fs:%1,%0"                      \
 118                     : "=r" (__i)                                        \
 119                     : "m" (*(u_int *)(__pcpu_offset(name))));           \
 120                 __result = *(__pcpu_type(name) *)(void *)&__i;          \
 121         } else {                                                        \
 122                 __result = *__PCPU_PTR(name);                           \
 123         }                                                               \
 124                                                                         \
 125         __result;                                                       \
 126 })
 127
 128 /*
 129  * Sets the value of the per-cpu variable name to value val.
 130  */
 131 #define __PCPU_SET(name, val) {                                         \
 132         __pcpu_type(name) __val = (val);                                \
 133                                                                         \
 134         if (sizeof(__val) == 1) {                                       \
 135                 u_char __b;                                             \
 136                 __b = *(u_char *)&__val;                                \
 137                 __asm __volatile("movb %1,%%fs:%0"                      \
 138                     : "=m" (*(u_char *)(__pcpu_offset(name)))           \
 139                     : "r" (__b));                                       \
 140         } else if (sizeof(__val) == 2) {                                \
 141                 u_short __w;                                            \
 142                 __w = *(u_short *)&__val;                               \
 143                 __asm __volatile("movw %1,%%fs:%0"                      \
 144                     : "=m" (*(u_short *)(__pcpu_offset(name)))          \
 145                     : "r" (__w));                                       \
 146         } else if (sizeof(__val) == 4) {                                \
 147                 u_int __i;                                              \
 148                 __i = *(u_int *)&__val;                                 \
 149                 __asm __volatile("movl %1,%%fs:%0"                      \
 150                     : "=m" (*(u_int *)(__pcpu_offset(name)))            \
 151                     : "r" (__i));                                       \
 152         } else {                                                        \
 153                 *__PCPU_PTR(name) = __val;                              \
 154         }                                                               \
 155 }
 156
 157 #define PCPU_GET(member)        __PCPU_GET(pc_ ## member)
 158 #define PCPU_PTR(member)        __PCPU_PTR(pc_ ## member)
 159 #define PCPU_SET(member, val)   __PCPU_SET(pc_ ## member, val)
 160
 161 static __inline struct thread *
 162 __curthread(void)
 163 {
 164         struct thread *td;
 165
 166         __asm __volatile("movl %%fs:0,%0" : "=r" (td));
 167         return (td);
 168 }
 169 #define curthread (__curthread())
 170
 171 #else
 172 #error this file needs to be ported to your compiler
 173 #endif
 174
 175 #endif  /* _KERNEL */
 176
 177 #endif  /* ! _MACHINE_PCPU_H_ */