sys/sys/upmap.h

   1 /*
   2  * Copyright (c) 2014 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  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
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #ifndef _SYS_UPMAP_H_
  36 #define _SYS_UPMAP_H_
  37
  38 #ifndef _SYS_TYPES_H_
  39 #include <sys/types.h>
  40 #endif
  41 #ifndef _SYS_TIME_H_
  42 #include <sys/time.h>
  43 #endif
  44
  45 #define UPMAP_MAXPROCTITLE      1024
  46 #define UPMAP_MAPSIZE           65536
  47 #define KPMAP_MAPSIZE           65536
  48
  49 #define UPMAP_VERSION           1
  50 #define KPMAP_VERSION           1
  51
  52 typedef uint64_t        forkid_t;
  53
  54 typedef struct ukpheader {
  55         uint16_t        type;           /* element type */
  56         uint16_t        offset;         /* offset from map base, max 65535 */
  57 } ukpheader_t;
  58
  59 #define UKPLEN_MASK             0x0F00
  60 #define UKPLEN_1                0x0000
  61 #define UKPLEN_2                0x0100
  62 #define UKPLEN_4                0x0200
  63 #define UKPLEN_8                0x0300
  64 #define UKPLEN_16               0x0400
  65 #define UKPLEN_32               0x0500
  66 #define UKPLEN_64               0x0600
  67 #define UKPLEN_128              0x0700
  68 #define UKPLEN_256              0x0800
  69 #define UKPLEN_512              0x0900
  70 #define UKPLEN_1024             0x0A00
  71
  72 #define UKPLEN_TS               ((sizeof(struct timespec) == 8) ? \
  73                                         UKPLEN_16 : UKPLEN_32)
  74 #define UKPLEN_DECODE(type)     (1 << ((type >> 8) & 0x0F))
  75
  76 #define UKPTYPE_VERSION         (0x0001 | UKPLEN_4)     /* always first */
  77
  78 #define UPTYPE_RUNTICKS         (0x0010 | UKPLEN_4)
  79 #define UPTYPE_FORKID           (0x0011 | UKPLEN_8)
  80 #define UPTYPE_PID              (0x0012 | UKPLEN_4)
  81 #define UPTYPE_PROC_TITLE       (0x0013 | UKPLEN_1024)
  82 #define UPTYPE_INVFORK          (0x0014 | UKPLEN_4)
  83
  84 #define KPTYPE_UPTICKS          (0x8000 | UKPLEN_4)
  85 #define KPTYPE_TS_UPTIME        (0x8001 | UKPLEN_TS)
  86 #define KPTYPE_TS_REALTIME      (0x8002 | UKPLEN_TS)
  87 #define KPTYPE_TSC_FREQ         (0x8003 | UKPLEN_8)
  88 #define KPTYPE_TICK_FREQ        (0x8004 | UKPLEN_8)
  89
  90 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
  91
  92 /*
  93  * (writable) user per-process map via /dev/upmap.
  94  *
  95  * ABSOLUTE LOCATIONS CAN CHANGE, ITERATE HEADERS FOR THE TYPE YOU DESIRE
  96  * UNTIL YOU HIT TYPE 0, THEN CACHE THE RESULTING POINTER.
  97  *
  98  * If you insist, at least check that the version matches UPMAP_VERSION.
  99  */
 100 struct sys_upmap {
 101         ukpheader_t     header[64];
 102         uint32_t        version;
 103         uint32_t        runticks;       /* running scheduler ticks */
 104         forkid_t        forkid;         /* unique 2^64 (fork detect) NOT MONO */
 105         uint32_t        invfork;        /* vfork active */
 106         pid_t           pid;            /* process id */
 107         uint32_t        reserved[16];
 108         char            proc_title[UPMAP_MAXPROCTITLE];
 109 };
 110
 111 /*
 112  * (read-only) kernel per-cpu map via /dev/kpmap.
 113  *
 114  * ABSOLUTE LOCATIONS CAN CHANGE, ITERATE HEADERS FOR THE TYPE YOU DESIRE
 115  * UNTIL YOU HIT TYPE 0, THEN CACHE THE RESULTING POINTER.
 116  *
 117  * If you insist, at least check that the version matches KPMAP_VERSION.
 118  *
 119  * Procedure for reading stable values from ts_uptime/ts_realtime.  This
 120  * avoids looping in nearly all cases, including during a kernel update.
 121  * The only case where this might loop is if the kernel deschedules
 122  * the user thread for more than 1 tick.
 123  *
 124  *      do {
 125  *              w = upticks;
 126  *              cpu_lfence();
 127  *              load ts_uptime[w & 1] or ts_realtime[w & 1]
 128  *              cpu_lfence();
 129  *              w = upticks - w;
 130  *      } while (w > 1);
 131  */
 132 struct sys_kpmap {
 133         ukpheader_t     header[64];
 134         int32_t         version;
 135         int32_t         upticks;        /* userland reads ts_*[upticks & 1] */
 136         struct timespec ts_uptime[2];   /* mono uptime @ticks (uncompensated) */
 137         struct timespec ts_realtime[2]; /* realtime @ticks resolution */
 138         int64_t         tsc_freq;       /* (if supported by cpu) */
 139         int32_t         tick_freq;      /* scheduler tick frequency */
 140 };
 141
 142 #endif
 143
 144 #ifdef _KERNEL
 145 extern struct sys_kpmap *kpmap;
 146 #endif
 147
 148 #endif