tools/perf/tests/shell/record+probe_libc_inet_pton.sh

   1 #!/bin/sh
   2 # probe libc's inet_pton & backtrace it with ping
   3
   4 # Installs a probe on libc's inet_pton function, that will use uprobes,
   5 # then use 'perf trace' on a ping to localhost asking for just one packet
   6 # with the a backtrace 3 levels deep, check that it is what we expect.
   7 # This needs no debuginfo package, all is done using the libc ELF symtab
   8 # and the CFI info in the binaries.
   9
  10 # SPDX-License-Identifier: GPL-2.0
  11 # Arnaldo Carvalho de Melo <acme@kernel.org>, 2017
  12
  13 . $(dirname $0)/lib/probe.sh
  14
  15 libc=$(grep -w libc /proc/self/maps | head -1 | sed -r 's/.*[[:space:]](\/.*)/\1/g')
  16 nm -Dg $libc 2>/dev/null | fgrep -q inet_pton || exit 254
  17
  18 event_pattern='probe_libc:inet_pton(\_[[:digit:]]+)?'
  19
  20 add_libc_inet_pton_event() {
  21
  22         event_name=$(perf probe -f -x $libc -a inet_pton 2>&1 | tail -n +2 | head -n -5 | \
  23                         grep -P -o "$event_pattern(?=[[:space:]]\(on inet_pton in $libc\))")
  24
  25         if [ $? -ne 0 -o -z "$event_name" ] ; then
  26                 printf "FAIL: could not add event\n"
  27                 return 1
  28         fi
  29 }
  30
  31 trace_libc_inet_pton_backtrace() {
  32
  33         expected=`mktemp -u /tmp/expected.XXX`
  34
  35         echo "ping[][0-9 \.:]+$event_name: \([[:xdigit:]]+\)" > $expected
  36         echo ".*inet_pton\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
  37         case "$(uname -m)" in
  38         s390x)
  39                 eventattr='call-graph=dwarf,max-stack=4'
  40                 echo "gaih_inet.*\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
  41                 echo "(__GI_)?getaddrinfo\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
  42                 echo "main\+0x[[:xdigit:]]+[[:space:]]\(.*/bin/ping.*\)$" >> $expected
  43                 ;;
  44         ppc64|ppc64le)
  45                 eventattr='max-stack=4'
  46                 echo "gaih_inet.*\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
  47                 echo "getaddrinfo\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
  48                 echo ".*(\+0x[[:xdigit:]]+|\[unknown\])[[:space:]]\(.*/bin/ping.*\)$" >> $expected
  49                 ;;
  50         *)
  51                 eventattr='max-stack=3'
  52                 echo "getaddrinfo\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
  53                 echo ".*(\+0x[[:xdigit:]]+|\[unknown\])[[:space:]]\(.*/bin/ping.*\)$" >> $expected
  54                 ;;
  55         esac
  56
  57         perf_data=`mktemp -u /tmp/perf.data.XXX`
  58         perf_script=`mktemp -u /tmp/perf.script.XXX`
  59         perf record -e $event_name/$eventattr/ -o $perf_data ping -6 -c 1 ::1 > /dev/null 2>&1
  60         perf script -i $perf_data > $perf_script
  61
  62         exec 3<$perf_script
  63         exec 4<$expected
  64         while read line <&3 && read -r pattern <&4; do
  65                 [ -z "$pattern" ] && break
  66                 echo $line
  67                 echo "$line" | egrep -q "$pattern"
  68                 if [ $? -ne 0 ] ; then
  69                         printf "FAIL: expected backtrace entry \"%s\" got \"%s\"\n" "$pattern" "$line"
  70                         return 1
  71                 fi
  72         done
  73
  74         # If any statements are executed from this point onwards,
  75         # the exit code of the last among these will be reflected
  76         # in err below. If the exit code is 0, the test will pass
  77         # even if the perf script output does not match.
  78 }
  79
  80 delete_libc_inet_pton_event() {
  81
  82         if [ -n "$event_name" ] ; then
  83                 perf probe -q -d $event_name
  84         fi
  85 }
  86
  87 # Check for IPv6 interface existence
  88 ip a sh lo | fgrep -q inet6 || exit 2
  89
  90 skip_if_no_perf_probe && \
  91 add_libc_inet_pton_event && \
  92 trace_libc_inet_pton_backtrace
  93 err=$?
  94 rm -f ${perf_data} ${perf_script} ${expected}
  95 delete_libc_inet_pton_event
  96 exit $err