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

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