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
  47 #define PCPU_MD_FIELDS                                                  \
  48         char    pc_monitorbuf[128] __aligned(128); /* cache line */     \
  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         u_int   pc_cmci_mask;           /* MCx banks for CMCI */        \
  60         u_int   pc_vcpu_id;             /* Xen vCPU ID */               \
  61         char    __pad[233]
  62
  63 #ifdef _KERNEL
  64
  65 #ifdef lint
  66
  67 extern struct pcpu *pcpup;
  68
  69 #define PCPU_GET(member)        (pcpup->pc_ ## member)
  70 #define PCPU_ADD(member, val)   (pcpup->pc_ ## member += (val))
  71 #define PCPU_INC(member)        PCPU_ADD(member, 1)
  72 #define PCPU_PTR(member)        (&pcpup->pc_ ## member)
  73 #define PCPU_SET(member, val)   (pcpup->pc_ ## member = (val))
  74
  75 #elif defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF)
  76
  77 /*
  78  * Evaluates to the byte offset of the per-cpu variable name.
  79  */
  80 #define __pcpu_offset(name)                                             \
  81         __offsetof(struct pcpu, name)
  82
  83 /*
  84  * Evaluates to the type of the per-cpu variable name.
  85  */
  86 #define __pcpu_type(name)                                               \
  87         __typeof(((struct pcpu *)0)->name)
  88
  89 /*
  90  * Evaluates to the address of the per-cpu variable name.
  91  */
  92 #define __PCPU_PTR(name) __extension__ ({                               \
  93         __pcpu_type(name) *__p;                                         \
  94                                                                         \
  95         __asm __volatile("movl %%fs:%1,%0; addl %2,%0"                  \
  96             : "=r" (__p)                                                \
  97             : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),       \
  98               "i" (__pcpu_offset(name)));                               \
  99                                                                         \
 100         __p;                                                            \
 101 })
 102
 103 /*
 104  * Evaluates to the value of the per-cpu variable name.
 105  */
 106 #define __PCPU_GET(name) __extension__ ({                               \
 107         __pcpu_type(name) __res;                                        \
 108         struct __s {                                                    \
 109                 u_char  __b[MIN(sizeof(__res), 4)];                     \
 110         } __s;                                                          \
 111                                                                         \
 112         if (sizeof(__res) == 1 || sizeof(__res) == 2 ||                 \
 113             sizeof(__res) == 4) {                                       \
 114                 __asm __volatile("mov %%fs:%1,%0"                       \
 115                     : "=r" (__s)                                        \
 116                     : "m" (*(struct __s *)(__pcpu_offset(name))));      \
 117                 *(struct __s *)(void *)&__res = __s;                    \
 118         } else {                                                        \
 119                 __res = *__PCPU_PTR(name);                              \
 120         }                                                               \
 121         __res;                                                          \
 122 })
 123
 124 /*
 125  * Adds a value of the per-cpu counter name.  The implementation
 126  * must be atomic with respect to interrupts.
 127  */
 128 #define __PCPU_ADD(name, val) do {                                      \
 129         __pcpu_type(name) __val;                                        \
 130         struct __s {                                                    \
 131                 u_char  __b[MIN(sizeof(__val), 4)];                     \
 132         } __s;                                                          \
 133                                                                         \
 134         __val = (val);                                                  \
 135         if (sizeof(__val) == 1 || sizeof(__val) == 2 ||                 \
 136             sizeof(__val) == 4) {                                       \
 137                 __s = *(struct __s *)(void *)&__val;                    \
 138                 __asm __volatile("add %1,%%fs:%0"                       \
 139                     : "=m" (*(struct __s *)(__pcpu_offset(name)))       \
 140                     : "r" (__s));                                       \
 141         } else                                                          \
 142                 *__PCPU_PTR(name) += __val;                             \
 143 } while (0)
 144
 145 /*
 146  * Increments the value of the per-cpu counter name.  The implementation
 147  * must be atomic with respect to interrupts.
 148  */
 149 #define __PCPU_INC(name) do {                                           \
 150         CTASSERT(sizeof(__pcpu_type(name)) == 1 ||                      \
 151             sizeof(__pcpu_type(name)) == 2 ||                           \
 152             sizeof(__pcpu_type(name)) == 4);                            \
 153         if (sizeof(__pcpu_type(name)) == 1) {                           \
 154                 __asm __volatile("incb %%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)) == 2) {                    \
 158                 __asm __volatile("incw %%fs:%0"                         \
 159                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 160                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 161         } else if (sizeof(__pcpu_type(name)) == 4) {                    \
 162                 __asm __volatile("incl %%fs:%0"                         \
 163                     : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
 164                     : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
 165         }                                                               \
 166 } while (0)
 167
 168 /*
 169  * Sets the value of the per-cpu variable name to value val.
 170  */
 171 #define __PCPU_SET(name, val) do {                                      \
 172         __pcpu_type(name) __val;                                        \
 173         struct __s {                                                    \
 174                 u_char  __b[MIN(sizeof(__val), 4)];                     \
 175         } __s;                                                          \
 176                                                                         \
 177         __val = (val);                                                  \
 178         if (sizeof(__val) == 1 || sizeof(__val) == 2 ||                 \
 179             sizeof(__val) == 4) {                                       \
 180                 __s = *(struct __s *)(void *)&__val;                    \
 181                 __asm __volatile("mov %1,%%fs:%0"                       \
 182                     : "=m" (*(struct __s *)(__pcpu_offset(name)))       \
 183                     : "r" (__s));                                       \
 184         } else {                                                        \
 185                 *__PCPU_PTR(name) = __val;                              \
 186         }                                                               \
 187 } while (0)
 188
 189 #define PCPU_GET(member)        __PCPU_GET(pc_ ## member)
 190 #define PCPU_ADD(member, val)   __PCPU_ADD(pc_ ## member, val)
 191 #define PCPU_INC(member)        __PCPU_INC(pc_ ## member)
 192 #define PCPU_PTR(member)        __PCPU_PTR(pc_ ## member)
 193 #define PCPU_SET(member, val)   __PCPU_SET(pc_ ## member, val)
 194
 195 #define OFFSETOF_CURTHREAD      0
 196 #ifdef __clang__
 197 #pragma clang diagnostic push
 198 #pragma clang diagnostic ignored "-Wnull-dereference"
 199 #endif
 200 static __inline __pure2 struct thread *
 201 __curthread(void)
 202 {
 203         struct thread *td;
 204
 205         __asm("movl %%fs:%1,%0" : "=r" (td)
 206             : "m" (*(char *)OFFSETOF_CURTHREAD));
 207         return (td);
 208 }
 209 #ifdef __clang__
 210 #pragma clang diagnostic pop
 211 #endif
 212 #define curthread               (__curthread())
 213
 214 #define OFFSETOF_CURPCB         16
 215 static __inline __pure2 struct pcb *
 216 __curpcb(void)
 217 {
 218         struct pcb *pcb;
 219
 220         __asm("movl %%fs:%1,%0" : "=r" (pcb) : "m" (*(char *)OFFSETOF_CURPCB));
 221         return (pcb);
 222 }
 223 #define curpcb          (__curpcb())
 224
 225 #else /* !lint || defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF) */
 226
 227 #error "this file needs to be ported to your compiler"
 228
 229 #endif /* lint, etc. */
 230
 231 #endif /* _KERNEL */
 232
 233 #endif /* !_MACHINE_PCPU_H_ */