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 $libc 2>/dev/null | fgrep -q inet_pton || exit 254
  15
  16 event_pattern='probe_libc:inet_pton(\_[[:digit:]]+)?'
  17
  18 add_libc_inet_pton_event() {
  19
  20         event_name=$(perf probe -f -x $libc -a inet_pton 2>&1 | tail -n +2 | head -n -5 | \
  21                         grep -P -o "$event_pattern(?=[[:space:]]\(on inet_pton in $libc\))")
  22
  23         if [ $? -ne 0 -o -z "$event_name" ] ; then
  24                 printf "FAIL: could not add event\n"
  25                 return 1
  26         fi
  27 }
  28
  29 trace_libc_inet_pton_backtrace() {
  30
  31         expected=`mktemp -u /tmp/expected.XXX`
  32
  33         echo "ping[][0-9 \.:]+$event_name: \([[:xdigit:]]+\)" > $expected
  34         echo ".*inet_pton\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
  35         case "$(uname -m)" in
  36         s390x)
  37                 eventattr='call-graph=dwarf,max-stack=4'
  38                 echo "gaih_inet.*\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
  39                 echo "(__GI_)?getaddrinfo\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
  40                 echo "main\+0x[[:xdigit:]]+[[:space:]]\(.*/bin/ping.*\)$" >> $expected
  41                 ;;
  42         ppc64|ppc64le)
  43                 eventattr='max-stack=4'
  44                 echo "gaih_inet.*\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
  45                 echo "getaddrinfo\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
  46                 echo ".*(\+0x[[:xdigit:]]+|\[unknown\])[[:space:]]\(.*/bin/ping.*\)$" >> $expected
  47                 ;;
  48         *)
  49                 eventattr='max-stack=3'
  50                 echo "getaddrinfo\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
  51                 echo ".*(\+0x[[:xdigit:]]+|\[unknown\])[[:space:]]\(.*/bin/ping.*\)$" >> $expected
  52                 ;;
  53         esac
  54
  55         perf_data=`mktemp -u /tmp/perf.data.XXX`
  56         perf_script=`mktemp -u /tmp/perf.script.XXX`
  57         perf record -e $event_name/$eventattr/ -o $perf_data ping -6 -c 1 ::1 > /dev/null 2>&1
  58         perf script -i $perf_data > $perf_script
  59
  60         exec 3<$perf_script
  61         exec 4<$expected
  62         while read line <&3 && read -r pattern <&4; do
  63                 [ -z "$pattern" ] && break
  64                 echo $line
  65                 echo "$line" | egrep -q "$pattern"
  66                 if [ $? -ne 0 ] ; then
  67                         printf "FAIL: expected backtrace entry \"%s\" got \"%s\"\n" "$pattern" "$line"
  68                         return 1
  69                 fi
  70         done
  71
  72         # If any statements are executed from this point onwards,
  73         # the exit code of the last among these will be reflected
  74         # in err below. If the exit code is 0, the test will pass
  75         # even if the perf script output does not match.
  76 }
  77
  78 delete_libc_inet_pton_event() {
  79
  80         if [ -n "$event_name" ] ; then
  81                 perf probe -q -d $event_name
  82         fi
  83 }
  84
  85 # Check for IPv6 interface existence
  86 ip a sh lo | fgrep -q inet6 || exit 2
  87
  88 skip_if_no_perf_probe && \
  89 add_libc_inet_pton_event && \
  90 trace_libc_inet_pton_backtrace
  91 err=$?
  92 rm -f ${perf_data} ${perf_script} ${expected}
  93 delete_libc_inet_pton_event
  94 exit $err