sys/i386/include/pcpu.h

   1 /*-
   2  * Copyright (c) Peter Wemm
   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 "sys/cdefs.h is a prerequisite for this file"
  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;             /* ACPI CPU id */               \
  57         u_int   pc_apic_id;                                             \
  58         int     pc_private_tss          /* Flag indicating private tss */
  59
  60 #ifdef lint
  61
  62 extern struct pcpu *pcpup;
  63
  64 #define PCPU_GET(member)        (pcpup->pc_ ## member)
  65 #define PCPU_LAZY_INC(member)   (++pcpup->pc_ ## member)
  66 #define PCPU_PTR(member)        (&pcpup->pc_ ## member)
  67 #define PCPU_SET(member, val)   (pcpup->pc_ ## member = (val))
  68
  69 #elif defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF)
  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) __res;                                        \
 102         struct __s {                                                    \
 103                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 104         } __s;                                                          \
 105                                                                         \
 106         if (sizeof(__res) == 1 || sizeof(__res) == 2 ||                 \
 107             sizeof(__res) == 4) {                                       \
 108                 __asm __volatile("mov %%fs:%1,%0"                       \
 109                     : "=r" (__s)                                        \
 110                     : "m" (*(struct __s *)(__pcpu_offset(name))));      \
 111                 *(struct __s *)(void *)&__res = __s;                    \
 112         } else {                                                        \
 113                 __res = *__PCPU_PTR(name);                              \
 114         }                                                               \
 115         __res;                                                          \
 116 })
 117
 118 /*
 119  * Increments the value of the per-cpu counter name.  The implementation
 120  * must be atomic with respect to interrupts.
 121  */
 122 #define __PCPU_LAZY_INC(name) do {                                      \
 123         CTASSERT(sizeof(__pcpu_type(name)) == 1 ||                      \
 124             sizeof(__pcpu_type(name)) == 2 ||                           \
 125             sizeof(__pcpu_type(name)) == 4);                            \
 126         if (sizeof(__pcpu_type(name)) == 1) {                           \
 127                 __asm __volatile("incb %%fs:%0"                         \
 128                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 129                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 130         } else if (sizeof(__pcpu_type(name)) == 2) {                    \
 131                 __asm __volatile("incw %%fs:%0"                         \
 132                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 133                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 134         } else if (sizeof(__pcpu_type(name)) == 4) {                    \
 135                 __asm __volatile("incl %%fs:%0"                         \
 136                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 137                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 138         }                                                               \
 139 } while (0)
 140
 141 /*
 142  * Sets the value of the per-cpu variable name to value val.
 143  */
 144 #define __PCPU_SET(name, val) {                                         \
 145         __pcpu_type(name) __val;                                        \
 146         struct __s {                                                    \
 147                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 148         } __s;                                                          \
 149                                                                         \
 150         __val = (val);                                                  \
 151         if (sizeof(__val) == 1 || sizeof(__val) == 2 ||                 \
 152             sizeof(__val) == 4) {                                       \
 153                 __s = *(struct __s *)(void *)&__val;                    \
 154                 __asm __volatile("mov %1,%%fs:%0"                       \
 155                     : "=m" (*(struct __s *)(__pcpu_offset(name)))       \
 156                     : "r" (__s));                                       \
 157         } else {                                                        \
 158                 *__PCPU_PTR(name) = __val;                              \
 159         }                                                               \
 160 }
 161
 162 #define PCPU_GET(member)        __PCPU_GET(pc_ ## member)
 163 #define PCPU_LAZY_INC(member)   __PCPU_LAZY_INC(pc_ ## member)
 164 #define PCPU_PTR(member)        __PCPU_PTR(pc_ ## member)
 165 #define PCPU_SET(member, val)   __PCPU_SET(pc_ ## member, val)
 166
 167 static __inline struct thread *
 168 __curthread(void)
 169 {
 170         struct thread *td;
 171
 172         __asm __volatile("movl %%fs:0,%0" : "=r" (td));
 173         return (td);
 174 }
 175 #define curthread               (__curthread())
 176
 177 #else /* !lint || defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF) */
 178
 179 #error "this file needs to be ported to your compiler"
 180
 181 #endif /* lint, etc. */
 182
 183 #endif /* _KERNEL */
 184
 185 #endif /* !_MACHINE_PCPU_H_ */