sys/compat/linux/trace_futexes.d

   1 #!/usr/sbin/dtrace -qs
   2
   3 /*-
   4  * Copyright (c) 2011-2012 Alexander Leidinger <netchild@FreeBSD.org>
   5  * All rights reserved.
   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  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer
  12  *    in this position and unchanged.
  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  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * $FreeBSD$
  29  */
  30
  31 /**
  32  * Trace futex operations:
  33  *  - internal locks
  34  *  - size of the futex list
  35  *  - report error conditions (emulation errors, kernel errors,
  36  *    programming errors)
  37  *  - execution time (wallclock) of futex related functions
  38  */
  39
  40 #pragma D option specsize=32m
  41
  42 /* Error conditions */
  43 linuxulator*:futex:futex_get:error,
  44 linuxulator*:futex:futex_sleep:requeue_error,
  45 linuxulator*:futex:futex_sleep:sleep_error,
  46 linuxulator*:futex:futex_wait:copyin_error,
  47 linuxulator*:futex:futex_wait:itimerfix_error,
  48 linuxulator*:futex:futex_wait:sleep_error,
  49 linuxulator*:futex:futex_atomic_op:missing_access_check,
  50 linuxulator*:futex:futex_atomic_op:unimplemented_op,
  51 linuxulator*:futex:futex_atomic_op:unimplemented_cmp,
  52 linuxulator*:futex:linux_sys_futex:unimplemented_clockswitch,
  53 linuxulator*:futex:linux_sys_futex:copyin_error,
  54 linuxulator*:futex:linux_sys_futex:unhandled_efault,
  55 linuxulator*:futex:linux_sys_futex:unimplemented_lock_pi,
  56 linuxulator*:futex:linux_sys_futex:unimplemented_unlock_pi,
  57 linuxulator*:futex:linux_sys_futex:unimplemented_trylock_pi,
  58 linuxulator*:futex:linux_sys_futex:unimplemented_wait_requeue_pi,
  59 linuxulator*:futex:linux_sys_futex:unimplemented_cmp_requeue_pi,
  60 linuxulator*:futex:linux_sys_futex:unknown_operation,
  61 linuxulator*:futex:linux_get_robust_list:copyout_error,
  62 linuxulator*:futex:handle_futex_death:copyin_error,
  63 linuxulator*:futex:fetch_robust_entry:copyin_error,
  64 linuxulator*:futex:release_futexes:copyin_error
  65 {
  66         printf("ERROR: %s in %s:%s:%s\n", probename, probeprov, probemod,
  67             probefunc);
  68         stack();
  69         ustack();
  70 }
  71
  72 linuxulator*:futex:linux_sys_futex:invalid_cmp_requeue_use,
  73 linuxulator*:futex:linux_sys_futex:deprecated_requeue,
  74 linuxulator*:futex:linux_set_robust_list:size_error
  75 {
  76         printf("WARNING: %s:%s:%s:%s in application %s, maybe an application error?\n",
  77             probename, probeprov, probemod, probefunc, execname);
  78         stack();
  79         ustack();
  80 }
  81
  82
  83 /* Per futex checks/statistics */
  84
  85 linuxulator*:futex:futex:create
  86 {
  87         ++futex_count;
  88         @max_futexes = max(futex_count);
  89 }
  90
  91 linuxulator*:futex:futex:destroy
  92 /futex_count == 0/
  93 {
  94         printf("ERROR: Request to destroy a futex which was not created,\n");
  95         printf("       or this script was started after some futexes where\n");
  96         printf("       created. Stack trace:\n");
  97         stack();
  98         ustack();
  99 }
 100
 101 linuxulator*:futex:futex:destroy
 102 {
 103         --futex_count;
 104 }
 105
 106
 107 /* Internal locks */
 108
 109 linuxulator*:locks:futex_mtx:locked
 110 {
 111         ++check[probefunc, arg0];
 112         @stats[probefunc] = count();
 113
 114         ts[probefunc] = timestamp;
 115         spec[probefunc] = speculation();
 116         printf("Stacktrace of last lock operation of the %s:\n", probefunc);
 117         stack();
 118 }
 119
 120 linuxulator*:locks:futex_mtx:unlock
 121 /check[probefunc, arg0] == 0/
 122 {
 123         printf("ERROR: unlock attemt of unlocked %s (%p),", probefunc, arg0);
 124         printf("       missing SDT probe in kernel, or dtrace program started");
 125         printf("       while the %s was already held (race condition).", probefunc);
 126         printf("       Stack trace follows:");
 127         stack();
 128 }
 129
 130 linuxulator*:locks:futex_mtx:unlock
 131 {
 132         discard(spec[probefunc]);
 133         spec[probefunc] = 0;
 134         --check[probefunc, arg0];
 135 }
 136
 137 /* Timeout handling for internal locks */
 138
 139 tick-10s
 140 /spec["futex_mtx"] != 0 && timestamp - ts["futex_mtx"] >= 9999999000/
 141 {
 142         commit(spec["futex_mtx"]);
 143         spec["futex_mtx"] = 0;
 144 }
 145
 146
 147 /* Timing statistings */
 148
 149 linuxulator*:futex::entry
 150 {
 151         self->time[probefunc] = timestamp;
 152         @calls[probeprov, execname, probefunc] = count();
 153 }
 154
 155 linuxulator*:futex::return
 156 /self->time[probefunc] != 0/
 157 {
 158         this->timediff = self->time[probefunc] - timestamp;
 159
 160         @timestats[probeprov, execname, probefunc] = quantize(this->timediff);
 161         @longest[probeprov, probefunc] = max(this->timediff);
 162
 163         self->time[probefunc] = 0;
 164 }
 165
 166
 167 /* Statistics */
 168
 169 END
 170 {
 171         printf("Number of locks per type:");
 172         printa(@stats);
 173         printf("Number of maximum number of futexes in the futex list:");
 174         printa(@max_futexes);
 175         printf("Number of futexes still existing: %d", futex_count);
 176         printf("Number of calls per provider/application/kernel function:");
 177         printa(@calls);
 178         printf("Wallclock-timing statistics per provider/application/kernel function (in ns):");
 179         printa(@timestats);
 180         printf("Longest running (wallclock!) functions per provider (in ns):");
 181         printa(@longest);
 182 }