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_ADD(member, val)   (pcpu->pc_ ## member += (val))
  66 #define PCPU_INC(member)        PCPU_ADD(member, 1)
  67 #define PCPU_PTR(member)        (&pcpup->pc_ ## member)
  68 #define PCPU_SET(member, val)   (pcpup->pc_ ## member = (val))
  69
  70 #elif defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF)
  71
  72 /*
  73  * Evaluates to the byte offset of the per-cpu variable name.
  74  */
  75 #define __pcpu_offset(name)                                             \
  76         __offsetof(struct pcpu, name)
  77
  78 /*
  79  * Evaluates to the type of the per-cpu variable name.
  80  */
  81 #define __pcpu_type(name)                                               \
  82         __typeof(((struct pcpu *)0)->name)
  83
  84 /*
  85  * Evaluates to the address of the per-cpu variable name.
  86  */
  87 #define __PCPU_PTR(name) __extension__ ({                               \
  88         __pcpu_type(name) *__p;                                         \
  89                                                                         \
  90         __asm __volatile("movl %%fs:%1,%0; addl %2,%0"                  \
  91             : "=r" (__p)                                                \
  92             : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),       \
  93               "i" (__pcpu_offset(name)));                               \
  94                                                                         \
  95         __p;                                                            \
  96 })
  97
  98 /*
  99  * Evaluates to the value of the per-cpu variable name.
 100  */
 101 #define __PCPU_GET(name) __extension__ ({                               \
 102         __pcpu_type(name) __res;                                        \
 103         struct __s {                                                    \
 104                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 105         } __s;                                                          \
 106                                                                         \
 107         if (sizeof(__res) == 1 || sizeof(__res) == 2 ||                 \
 108             sizeof(__res) == 4) {                                       \
 109                 __asm __volatile("mov %%fs:%1,%0"                       \
 110                     : "=r" (__s)                                        \
 111                     : "m" (*(struct __s *)(__pcpu_offset(name))));      \
 112                 *(struct __s *)(void *)&__res = __s;                    \
 113         } else {                                                        \
 114                 __res = *__PCPU_PTR(name);                              \
 115         }                                                               \
 116         __res;                                                          \
 117 })
 118
 119 /*
 120  * Adds a value of the per-cpu counter name.  The implementation
 121  * must be atomic with respect to interrupts.
 122  */
 123 #define __PCPU_ADD(name, val) do {                                      \
 124         __pcpu_type(name) __val;                                        \
 125         struct __s {                                                    \
 126                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 127         } __s;                                                          \
 128                                                                         \
 129         __val = (val);                                                  \
 130         if (sizeof(__val) == 1 || sizeof(__val) == 2 ||                 \
 131             sizeof(__val) == 4) {                                       \
 132                 __s = *(struct __s *)(void *)&__val;                    \
 133                 __asm __volatile("add %1,%%fs:%0"                       \
 134                     : "=m" (*(struct __s *)(__pcpu_offset(name)))       \
 135                     : "r" (__s));                                       \
 136         } else                                                          \
 137                 *__PCPU_PTR(name) += __val;                             \
 138 } while (0)
 139
 140 /*
 141  * Increments the value of the per-cpu counter name.  The implementation
 142  * must be atomic with respect to interrupts.
 143  */
 144 #define __PCPU_INC(name) do {                                           \
 145         CTASSERT(sizeof(__pcpu_type(name)) == 1 ||                      \
 146             sizeof(__pcpu_type(name)) == 2 ||                           \
 147             sizeof(__pcpu_type(name)) == 4);                            \
 148         if (sizeof(__pcpu_type(name)) == 1) {                           \
 149                 __asm __volatile("incb %%fs:%0"                         \
 150                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 151                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 152         } else if (sizeof(__pcpu_type(name)) == 2) {                    \
 153                 __asm __volatile("incw %%fs:%0"                         \
 154                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 155                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 156         } else if (sizeof(__pcpu_type(name)) == 4) {                    \
 157                 __asm __volatile("incl %%fs:%0"                         \
 158                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 159                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 160         }                                                               \
 161 } while (0)
 162
 163 /*
 164  * Sets the value of the per-cpu variable name to value val.
 165  */
 166 #define __PCPU_SET(name, val) {                                         \
 167         __pcpu_type(name) __val;                                        \
 168         struct __s {                                                    \
 169                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 170         } __s;                                                          \
 171                                                                         \
 172         __val = (val);                                                  \
 173         if (sizeof(__val) == 1 || sizeof(__val) == 2 ||                 \
 174             sizeof(__val) == 4) {                                       \
 175                 __s = *(struct __s *)(void *)&__val;                    \
 176                 __asm __volatile("mov %1,%%fs:%0"                       \
 177                     : "=m" (*(struct __s *)(__pcpu_offset(name)))       \
 178                     : "r" (__s));                                       \
 179         } else {                                                        \
 180                 *__PCPU_PTR(name) = __val;                              \
 181         }                                                               \
 182 }
 183
 184 #define PCPU_GET(member)        __PCPU_GET(pc_ ## member)
 185 #define PCPU_ADD(member, val)   __PCPU_ADD(pc_ ## member, val)
 186 #define PCPU_INC(member)        __PCPU_INC(pc_ ## member)
 187 #define PCPU_PTR(member)        __PCPU_PTR(pc_ ## member)
 188 #define PCPU_SET(member, val)   __PCPU_SET(pc_ ## member, val)
 189
 190 static __inline struct thread *
 191 __curthread(void)
 192 {
 193         struct thread *td;
 194
 195         __asm __volatile("movl %%fs:0,%0" : "=r" (td));
 196         return (td);
 197 }
 198 #define curthread               (__curthread())
 199
 200 #else /* !lint || defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF) */
 201
 202 #error "this file needs to be ported to your compiler"
 203
 204 #endif /* lint, etc. */
 205
 206 #endif /* _KERNEL */
 207
 208 #endif /* !_MACHINE_PCPU_H_ */