sys/sys/pcpu.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 2001 Wind River Systems, Inc.
   5  * All rights reserved.
   6  * Written by: John Baldwin <jhb@FreeBSD.org>
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #ifndef _SYS_PCPU_H_
  34 #define _SYS_PCPU_H_
  35
  36 #ifdef LOCORE
  37 #error "no assembler-serviceable parts inside"
  38 #endif
  39
  40 #include <sys/param.h>
  41 #include <sys/_cpuset.h>
  42 #include <sys/_lock.h>
  43 #include <sys/_mutex.h>
  44 #include <sys/_sx.h>
  45 #include <sys/queue.h>
  46 #include <sys/_rmlock.h>
  47 #include <sys/resource.h>
  48 #include <machine/pcpu.h>
  49
  50 #define DPCPU_SETNAME           "set_pcpu"
  51 #define DPCPU_SYMPREFIX         "pcpu_entry_"
  52
  53 #ifdef _KERNEL
  54
  55 /*
  56  * Define a set for pcpu data.
  57  */
  58 extern uintptr_t *__start_set_pcpu;
  59 __GLOBL(__start_set_pcpu);
  60 extern uintptr_t *__stop_set_pcpu;
  61 __GLOBL(__stop_set_pcpu);
  62
  63 /*
  64  * Array of dynamic pcpu base offsets.  Indexed by id.
  65  */
  66 extern uintptr_t dpcpu_off[];
  67
  68 /*
  69  * Convenience defines.
  70  */
  71 #define DPCPU_START             ((uintptr_t)&__start_set_pcpu)
  72 #define DPCPU_STOP              ((uintptr_t)&__stop_set_pcpu)
  73 #define DPCPU_BYTES             (DPCPU_STOP - DPCPU_START)
  74 #define DPCPU_MODMIN            2048
  75 #define DPCPU_SIZE              roundup2(DPCPU_BYTES, PAGE_SIZE)
  76 #define DPCPU_MODSIZE           (DPCPU_SIZE - (DPCPU_BYTES - DPCPU_MODMIN))
  77
  78 /*
  79  * Declaration and definition.
  80  */
  81 #define DPCPU_NAME(n)           pcpu_entry_##n
  82 #define DPCPU_DECLARE(t, n)     extern t DPCPU_NAME(n)
  83 /* struct _hack is to stop this from being used with the static keyword. */
  84 #define DPCPU_DEFINE(t, n)      \
  85     struct _hack; t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
  86 #if defined(KLD_MODULE) && (defined(__aarch64__) || defined(__riscv) \
  87                 || defined(__powerpc64__) || defined(__i386__))
  88 /*
  89  * On some architectures the compiler will use PC-relative load to
  90  * find the address of DPCPU data with the static keyword. We then
  91  * use this to find the offset of the data in a per-CPU region.
  92  * This works for in the kernel as we can allocate the space ahead
  93  * of time, however modules need to allocate a sepatate space and
  94  * then use relocations to fix the address of the data. As
  95  * PC-relative data doesn't have a relocation there is nothing for
  96  * the kernel module linker to fix so data is accessed from the
  97  * wrong location.
  98  *
  99  * This is a workaround until a better solution can be found.
 100  *
 101  * VNET_DEFINE_STATIC also has the same workaround.
 102  */
 103 #define DPCPU_DEFINE_STATIC(t, n)       \
 104     t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
 105 #else
 106 #define DPCPU_DEFINE_STATIC(t, n)       \
 107     static t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
 108 #endif
 109
 110 /*
 111  * Accessors with a given base.
 112  */
 113 #define _DPCPU_PTR(b, n)                                                \
 114     (__typeof(DPCPU_NAME(n))*)((b) + (uintptr_t)&DPCPU_NAME(n))
 115 #define _DPCPU_GET(b, n)        (*_DPCPU_PTR(b, n))
 116 #define _DPCPU_SET(b, n, v)     (*_DPCPU_PTR(b, n) = v)
 117
 118 /*
 119  * Accessors for the current cpu.
 120  */
 121 #define DPCPU_PTR(n)            _DPCPU_PTR(PCPU_GET(dynamic), n)
 122 #define DPCPU_GET(n)            (*DPCPU_PTR(n))
 123 #define DPCPU_SET(n, v)         (*DPCPU_PTR(n) = v)
 124
 125 /*
 126  * Accessors for remote cpus.
 127  */
 128 #define DPCPU_ID_PTR(i, n)      _DPCPU_PTR(dpcpu_off[(i)], n)
 129 #define DPCPU_ID_GET(i, n)      (*DPCPU_ID_PTR(i, n))
 130 #define DPCPU_ID_SET(i, n, v)   (*DPCPU_ID_PTR(i, n) = v)
 131
 132 /*
 133  * Utility macros.
 134  */
 135 #define DPCPU_SUM(n) __extension__                                      \
 136 ({                                                                      \
 137         u_int _i;                                                       \
 138         __typeof(*DPCPU_PTR(n)) sum;                                    \
 139                                                                         \
 140         sum = 0;                                                        \
 141         CPU_FOREACH(_i) {                                               \
 142                 sum += *DPCPU_ID_PTR(_i, n);                            \
 143         }                                                               \
 144         sum;                                                            \
 145 })
 146
 147 #define DPCPU_VARSUM(n, var) __extension__                              \
 148 ({                                                                      \
 149         u_int _i;                                                       \
 150         __typeof((DPCPU_PTR(n))->var) sum;                              \
 151                                                                         \
 152         sum = 0;                                                        \
 153         CPU_FOREACH(_i) {                                               \
 154                 sum += (DPCPU_ID_PTR(_i, n))->var;                      \
 155         }                                                               \
 156         sum;                                                            \
 157 })
 158
 159 #define DPCPU_ZERO(n) do {                                              \
 160         u_int _i;                                                       \
 161                                                                         \
 162         CPU_FOREACH(_i) {                                               \
 163                 bzero(DPCPU_ID_PTR(_i, n), sizeof(*DPCPU_PTR(n)));      \
 164         }                                                               \
 165 } while (0)
 166
 167 #endif /* _KERNEL */
 168
 169 /*
 170  * This structure maps out the global data that needs to be kept on a
 171  * per-cpu basis.  The members are accessed via the PCPU_GET/SET/PTR
 172  * macros defined in <machine/pcpu.h>.  Machine dependent fields are
 173  * defined in the PCPU_MD_FIELDS macro defined in <machine/pcpu.h>.
 174  */
 175 struct pcpu {
 176         struct thread   *pc_curthread;          /* Current thread */
 177         struct thread   *pc_idlethread;         /* Idle thread */
 178         struct thread   *pc_fpcurthread;        /* Fp state owner */
 179         struct thread   *pc_deadthread;         /* Zombie thread or NULL */
 180         struct pcb      *pc_curpcb;             /* Current pcb */
 181         void            *pc_sched;              /* Scheduler state */
 182         uint64_t        pc_switchtime;          /* cpu_ticks() at last csw */
 183         int             pc_switchticks;         /* `ticks' at last csw */
 184         u_int           pc_cpuid;               /* This cpu number */
 185         STAILQ_ENTRY(pcpu) pc_allcpu;
 186         struct lock_list_entry *pc_spinlocks;
 187         long            pc_cp_time[CPUSTATES];  /* statclock ticks */
 188         struct _device  *pc_device;             /* CPU device handle */
 189         void            *pc_netisr;             /* netisr SWI cookie */
 190         int8_t          pc_vfs_freevnodes;      /* freevnodes counter */
 191         char            pc_unused1[3];          /* unused pad */
 192         int             pc_domain;              /* Memory domain. */
 193         struct rm_queue pc_rm_queue;            /* rmlock list of trackers */
 194         uintptr_t       pc_dynamic;             /* Dynamic per-cpu data area */
 195         uint64_t        pc_early_dummy_counter; /* Startup time counter(9) */
 196         uintptr_t       pc_zpcpu_offset;        /* Offset into zpcpu allocs */
 197
 198         /*
 199          * Keep MD fields last, so that CPU-specific variations on a
 200          * single architecture don't result in offset variations of
 201          * the machine-independent fields of the pcpu.  Even though
 202          * the pcpu structure is private to the kernel, some ports
 203          * (e.g., lsof, part of gtop) define _KERNEL and include this
 204          * header.  While strictly speaking this is wrong, there's no
 205          * reason not to keep the offsets of the MI fields constant
 206          * if only to make kernel debugging easier.
 207          */
 208         PCPU_MD_FIELDS;
 209 } __aligned(CACHE_LINE_SIZE);
 210
 211 #ifdef _KERNEL
 212
 213 STAILQ_HEAD(cpuhead, pcpu);
 214
 215 extern struct cpuhead cpuhead;
 216 extern struct pcpu *cpuid_to_pcpu[];
 217
 218 #define curcpu          PCPU_GET(cpuid)
 219 #define curvidata       PCPU_GET(vidata)
 220
 221 #define UMA_PCPU_ALLOC_SIZE             PAGE_SIZE
 222
 223 #include <machine/pcpu_aux.h>
 224
 225 #ifndef curthread
 226 #define curthread       PCPU_GET(curthread)
 227 #endif
 228 #define curproc         (curthread->td_proc)
 229
 230 #ifndef ZPCPU_ASSERT_PROTECTED
 231 #define ZPCPU_ASSERT_PROTECTED() MPASS(curthread->td_critnest > 0)
 232 #endif
 233
 234 #ifndef zpcpu_offset_cpu
 235 #define zpcpu_offset_cpu(cpu)   (UMA_PCPU_ALLOC_SIZE * cpu)
 236 #endif
 237 #ifndef zpcpu_offset
 238 #define zpcpu_offset()          (PCPU_GET(zpcpu_offset))
 239 #endif
 240
 241 #ifndef zpcpu_base_to_offset
 242 #define zpcpu_base_to_offset(base) (base)
 243 #endif
 244 #ifndef zpcpu_offset_to_base
 245 #define zpcpu_offset_to_base(base) (base)
 246 #endif
 247
 248 /* Accessor to elements allocated via UMA_ZONE_PCPU zone. */
 249 #define zpcpu_get(base) ({                                                              \
 250         __typeof(base) _ptr = (void *)((char *)(base) + zpcpu_offset());                \
 251         _ptr;                                                                           \
 252 })
 253
 254 #define zpcpu_get_cpu(base, cpu) ({                                                     \
 255         __typeof(base) _ptr = (void *)((char *)(base) + zpcpu_offset_cpu(cpu));         \
 256         _ptr;                                                                           \
 257 })
 258
 259 /*
 260  * This operation is NOT atomic and does not post any barriers.
 261  * If you use this the assumption is that the target CPU will not
 262  * be modifying this variable.
 263  * If you need atomicity use xchg.
 264  * */
 265 #define zpcpu_replace(base, val) ({                                     \
 266         __typeof(val) *_ptr = zpcpu_get(base);                          \
 267         __typeof(val) _old;                                             \
 268                                                                         \
 269         _old = *_ptr;                                                   \
 270         *_ptr = val;                                                    \
 271         _old;                                                           \
 272 })
 273
 274 #define zpcpu_replace_cpu(base, val, cpu) ({                            \
 275         __typeof(val) *_ptr = zpcpu_get_cpu(base, cpu);                 \
 276         __typeof(val) _old;                                             \
 277                                                                         \
 278         _old = *_ptr;                                                   \
 279         *_ptr = val;                                                    \
 280         _old;                                                           \
 281 })
 282
 283 #ifndef zpcpu_set_protected
 284 #define zpcpu_set_protected(base, val) ({                               \
 285         ZPCPU_ASSERT_PROTECTED();                                       \
 286         __typeof(val) *_ptr = zpcpu_get(base);                          \
 287                                                                         \
 288         *_ptr = (val);                                                  \
 289 })
 290 #endif
 291
 292 #ifndef zpcpu_add_protected
 293 #define zpcpu_add_protected(base, val) ({                               \
 294         ZPCPU_ASSERT_PROTECTED();                                       \
 295         __typeof(val) *_ptr = zpcpu_get(base);                          \
 296                                                                         \
 297         *_ptr += (val);                                                 \
 298 })
 299 #endif
 300
 301 #ifndef zpcpu_sub_protected
 302 #define zpcpu_sub_protected(base, val) ({                               \
 303         ZPCPU_ASSERT_PROTECTED();                                       \
 304         __typeof(val) *_ptr = zpcpu_get(base);                          \
 305                                                                         \
 306         *_ptr -= (val);                                                 \
 307 })
 308 #endif
 309
 310 /*
 311  * Machine dependent callouts.  cpu_pcpu_init() is responsible for
 312  * initializing machine dependent fields of struct pcpu, and
 313  * db_show_mdpcpu() is responsible for handling machine dependent
 314  * fields for the DDB 'show pcpu' command.
 315  */
 316 void    cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size);
 317 void    db_show_mdpcpu(struct pcpu *pcpu);
 318
 319 void    *dpcpu_alloc(int size);
 320 void    dpcpu_copy(void *s, int size);
 321 void    dpcpu_free(void *s, int size);
 322 void    dpcpu_init(void *dpcpu, int cpuid);
 323 void    pcpu_destroy(struct pcpu *pcpu);
 324 struct  pcpu *pcpu_find(u_int cpuid);
 325 void    pcpu_init(struct pcpu *pcpu, int cpuid, size_t size);
 326
 327 #endif /* _KERNEL */
 328
 329 #endif /* !_SYS_PCPU_H_ */