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 #include <machine/segments.h>
  37 #include <machine/tss.h>
  38
  39 /*
  40  * The SMP parts are setup in pmap.c and locore.s for the BSP, and
  41  * mp_machdep.c sets up the data for the AP's to "see" when they awake.
  42  * The reason for doing it via a struct is so that an array of pointers
  43  * to each CPU's data can be set up for things like "check curproc on all
  44  * other processors"
  45  */
  46 #define PCPU_MD_FIELDS                                                  \
  47         struct  pcpu *pc_prvspace;      /* Self-reference */            \
  48         struct  pmap *pc_curpmap;                                       \
  49         struct  i386tss pc_common_tss;                                  \
  50         struct  segment_descriptor pc_common_tssd;                      \
  51         struct  segment_descriptor *pc_tss_gdt;                         \
  52         struct  segment_descriptor *pc_fsgs_gdt;                        \
  53         int     pc_currentldt;                                          \
  54         u_int   pc_acpi_id;             /* ACPI CPU id */               \
  55         u_int   pc_apic_id;                                             \
  56         int     pc_private_tss          /* Flag indicating private tss */
  57
  58
  59 #ifdef _KERNEL
  60
  61 #ifdef lint
  62
  63 extern struct pcpu *pcpup;
  64
  65 #define PCPU_GET(member)        (pcpup->pc_ ## member)
  66 #define PCPU_ADD(member, val)   (pcpu->pc_ ## member += (val))
  67 #define PCPU_INC(member)        PCPU_ADD(member, 1)
  68 #define PCPU_PTR(member)        (&pcpup->pc_ ## member)
  69 #define PCPU_SET(member, val)   (pcpup->pc_ ## member = (val))
  70
  71 #elif defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF)
  72
  73 /*
  74  * Evaluates to the byte offset of the per-cpu variable name.
  75  */
  76 #define __pcpu_offset(name)                                             \
  77         __offsetof(struct pcpu, name)
  78
  79 /*
  80  * Evaluates to the type of the per-cpu variable name.
  81  */
  82 #define __pcpu_type(name)                                               \
  83         __typeof(((struct pcpu *)0)->name)
  84
  85 /*
  86  * Evaluates to the address of the per-cpu variable name.
  87  */
  88 #define __PCPU_PTR(name) __extension__ ({                               \
  89         __pcpu_type(name) *__p;                                         \
  90                                                                         \
  91         __asm __volatile("movl %%fs:%1,%0; addl %2,%0"                  \
  92             : "=r" (__p)                                                \
  93             : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),       \
  94               "i" (__pcpu_offset(name)));                               \
  95                                                                         \
  96         __p;                                                            \
  97 })
  98
  99 /*
 100  * Evaluates to the value of the per-cpu variable name.
 101  */
 102 #define __PCPU_GET(name) __extension__ ({                               \
 103         __pcpu_type(name) __res;                                        \
 104         struct __s {                                                    \
 105                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 106         } __s;                                                          \
 107                                                                         \
 108         if (sizeof(__res) == 1 || sizeof(__res) == 2 ||                 \
 109             sizeof(__res) == 4) {                                       \
 110                 __asm __volatile("mov %%fs:%1,%0"                       \
 111                     : "=r" (__s)                                        \
 112                     : "m" (*(struct __s *)(__pcpu_offset(name))));      \
 113                 *(struct __s *)(void *)&__res = __s;                    \
 114         } else {                                                        \
 115                 __res = *__PCPU_PTR(name);                              \
 116         }                                                               \
 117         __res;                                                          \
 118 })
 119
 120 /*
 121  * Adds a value of the per-cpu counter name.  The implementation
 122  * must be atomic with respect to interrupts.
 123  */
 124 #define __PCPU_ADD(name, val) do {                                      \
 125         __pcpu_type(name) __val;                                        \
 126         struct __s {                                                    \
 127                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 128         } __s;                                                          \
 129                                                                         \
 130         __val = (val);                                                  \
 131         if (sizeof(__val) == 1 || sizeof(__val) == 2 ||                 \
 132             sizeof(__val) == 4) {                                       \
 133                 __s = *(struct __s *)(void *)&__val;                    \
 134                 __asm __volatile("add %1,%%fs:%0"                       \
 135                     : "=m" (*(struct __s *)(__pcpu_offset(name)))       \
 136                     : "r" (__s));                                       \
 137         } else                                                          \
 138                 *__PCPU_PTR(name) += __val;                             \
 139 } while (0)
 140
 141 /*
 142  * Increments the value of the per-cpu counter name.  The implementation
 143  * must be atomic with respect to interrupts.
 144  */
 145 #define __PCPU_INC(name) do {                                           \
 146         CTASSERT(sizeof(__pcpu_type(name)) == 1 ||                      \
 147             sizeof(__pcpu_type(name)) == 2 ||                           \
 148             sizeof(__pcpu_type(name)) == 4);                            \
 149         if (sizeof(__pcpu_type(name)) == 1) {                           \
 150                 __asm __volatile("incb %%fs:%0"                         \
 151                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 152                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 153         } else if (sizeof(__pcpu_type(name)) == 2) {                    \
 154                 __asm __volatile("incw %%fs:%0"                         \
 155                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 156                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 157         } else if (sizeof(__pcpu_type(name)) == 4) {                    \
 158                 __asm __volatile("incl %%fs:%0"                         \
 159                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 160                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 161         }                                                               \
 162 } while (0)
 163
 164 /*
 165  * Sets the value of the per-cpu variable name to value val.
 166  */
 167 #define __PCPU_SET(name, val) {                                         \
 168         __pcpu_type(name) __val;                                        \
 169         struct __s {                                                    \
 170                 u_char  __b[MIN(sizeof(__pcpu_type(name)), 4)];         \
 171         } __s;                                                          \
 172                                                                         \
 173         __val = (val);                                                  \
 174         if (sizeof(__val) == 1 || sizeof(__val) == 2 ||                 \
 175             sizeof(__val) == 4) {                                       \
 176                 __s = *(struct __s *)(void *)&__val;                    \
 177                 __asm __volatile("mov %1,%%fs:%0"                       \
 178                     : "=m" (*(struct __s *)(__pcpu_offset(name)))       \
 179                     : "r" (__s));                                       \
 180         } else {                                                        \
 181                 *__PCPU_PTR(name) = __val;                              \
 182         }                                                               \
 183 }
 184
 185 #define PCPU_GET(member)        __PCPU_GET(pc_ ## member)
 186 #define PCPU_ADD(member, val)   __PCPU_ADD(pc_ ## member, val)
 187 #define PCPU_INC(member)        __PCPU_INC(pc_ ## member)
 188 #define PCPU_PTR(member)        __PCPU_PTR(pc_ ## member)
 189 #define PCPU_SET(member, val)   __PCPU_SET(pc_ ## member, val)
 190
 191 static __inline struct thread *
 192 __curthread(void)
 193 {
 194         struct thread *td;
 195
 196         __asm __volatile("movl %%fs:0,%0" : "=r" (td));
 197         return (td);
 198 }
 199 #define curthread               (__curthread())
 200
 201 #else /* !lint || defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF) */
 202
 203 #error "this file needs to be ported to your compiler"
 204
 205 #endif /* lint, etc. */
 206
 207 #endif /* _KERNEL */
 208
 209 #endif /* !_MACHINE_PCPU_H_ */