usr/src/cmd/dtrace/test/tst/common/usdt/tst.deadstub.ksh

   1 #
   2 # This file and its contents are supplied under the terms of the
   3 # Common Development and Distribution License ("CDDL"), version 1.0.
   4 # You may only use this file in accordance with the terms of version
   5 # 1.0 of the CDDL.
   6 #
   7 # A full copy of the text of the CDDL should have accompanied this
   8 # source.  A copy of the CDDL is also available via the Internet at
   9 # http://www.illumos.org/license/CDDL.
  10 #
  11
  12 #
  13 # Copyright (c) 2017, Joyent, Inc. All rights reserved.
  14 #
  15
  16 #
  17 # This test attempts to reproduce a three-way deadlock between mod_lock,
  18 # dtrace_lock and P_PR_LOCK that is induced by shmsys having to go through
  19 # mod_hold_stub.
  20 #
  21 if [ $# != 1 ]; then
  22         echo expected one argument: '<'dtrace-path'>'
  23         exit 2
  24 fi
  25
  26 dtrace=$1
  27 DIR=/var/tmp/dtest.$$
  28
  29 mkdir $DIR
  30 cd $DIR
  31
  32 cat > prov.d <<EOF
  33 provider test_prov {
  34         probe ripraf();
  35 };
  36 EOF
  37
  38 $dtrace -h -s prov.d
  39 if [ $? -ne 0 ]; then
  40         print -u2 "failed to generate header file"
  41         exit 1
  42 fi
  43
  44 cat > test.c <<EOF
  45 #include <unistd.h>
  46 #include <stdlib.h>
  47 #include <sys/types.h>
  48 #include <sys/ipc.h>
  49 #include <sys/shm.h>
  50 #include <stdio.h>
  51 #include <stdlib.h>
  52 #include "prov.h"
  53
  54 void
  55 main(int argc)
  56 {
  57         void *addr;
  58         int shmid;
  59
  60         if (argc > 1) {
  61                 TEST_PROV_RIPRAF();
  62                 exit(0);
  63         }
  64
  65         shmid = shmget(IPC_PRIVATE, sizeof (int), IPC_CREAT | 0666);
  66
  67         if (shmid == -1) {
  68                 perror("shmget: ");
  69                 exit(1);
  70         }
  71
  72         if ((addr = shmat(shmid, NULL, 0)) == (void *)-1) {
  73                 perror("shmat: ");
  74                 exit(1);
  75         }
  76
  77         printf("%p\n", addr);
  78
  79         for (;;) {
  80                 TEST_PROV_RIPRAF();
  81                 sleep(1);
  82         }
  83 }
  84 EOF
  85
  86 gcc -m32 -c test.c
  87 if [ $? -ne 0 ]; then
  88         print -u2 "failed to compile test.c"
  89         exit 1
  90 fi
  91
  92 $dtrace -G -32 -s prov.d test.o
  93
  94 if [ $? -ne 0 ]; then
  95         print -u2 "failed to create DOF"
  96         exit 1
  97 fi
  98
  99 gcc -m32 -o test test.o prov.o
 100
 101 if [ $? -ne 0 ]; then
 102         print -u2 "failed to link final executable"
 103         exit 1
 104 fi
 105
 106 #
 107 # Kick off the victim program.
 108 #
 109 ./test &
 110
 111 victim=$!
 112
 113 #
 114 # Kick off a shell that will do nothing but read our victim's /proc map
 115 #
 116 ( while true ; do read foo < /proc/$victim/map ; done ) &
 117 stubby=$!
 118
 119 #
 120 # Kick off a shell that will do nothing but instrument (and de-instrument)
 121 # the victim
 122 #
 123 ( while true; do \
 124     $dtrace -q -P test_prov$victim -n BEGIN'{exit(0)}' > /dev/null ; done ) &
 125 inst=$!
 126
 127 #
 128 # Finally, kick off a shell that will cause lots of provider registration and
 129 # (importantly) de-registration
 130 #
 131 ( while true; do ./test foo ; done) &
 132 reg=$!
 133
 134 echo $DIR
 135 echo victim: $victim
 136 echo stubby: $stubby
 137 echo inst: $inst
 138 echo reg: $reg
 139
 140 sleep 120
 141
 142 kill $reg
 143 sleep 1
 144 kill $inst
 145 sleep 1
 146 kill $stubby
 147 sleep 1
 148 kill $victim
 149
 150 #
 151 # If we're deadlocked, this DTrace enabling won't work (if we even make it this
 152 # far, which seems unlikely).  In the spirit of the deadlock, we denote our
 153 # success by emiting a classic Faulknerism.
 154 #
 155 raf="Maybe you're not so worthless!"
 156 dtrace -qn BEGIN"{printf(\"$raf\"); exit(0)}"
 157
 158 cd /
 159 /usr/bin/rm -rf $DIR
 160
 161 exit 0