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 . $(dirname $0)/lib/probe_vfs_getname.sh
  15
  16 libc=$(grep -w libc /proc/self/maps | head -1 | sed -r 's/.*[[:space:]](\/.*)/\1/g')
  17 nm -Dg $libc 2>/dev/null | fgrep -q inet_pton || exit 254
  18
  19 event_pattern='probe_libc:inet_pton(\_[[:digit:]]+)?'
  20
  21 add_libc_inet_pton_event() {
  22
  23         event_name=$(perf probe -f -x $libc -a inet_pton 2>&1 | tail -n +2 | head -n -5 | \
  24                         grep -P -o "$event_pattern(?=[[:space:]]\(on inet_pton in $libc\))")
  25
  26         if [ $? -ne 0 -o -z "$event_name" ] ; then
  27                 printf "FAIL: could not add event\n"
  28                 return 1
  29         fi
  30 }
  31
  32 trace_libc_inet_pton_backtrace() {
  33
  34         expected=`mktemp -u /tmp/expected.XXX`
  35
  36         echo "ping[][0-9 \.:]+$event_name: \([[:xdigit:]]+\)" > $expected
  37         echo ".*inet_pton\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
  38         case "$(uname -m)" in
  39         s390x)
  40                 eventattr='call-graph=dwarf,max-stack=4'
  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:]]\(.*/bin/ping.*\)$" >> $expected
  54                 ;;
  55         esac
  56
  57         perf_data=`mktemp -u /tmp/perf.data.XXX`
  58         perf_script=`mktemp -u /tmp/perf.script.XXX`
  59
  60         # Check presence of libtraceevent support to run perf record
  61         skip_no_probe_record_support "$event_name/$eventattr/"
  62         [ $? -eq 2 ] && return 2
  63
  64         perf record -e $event_name/$eventattr/ -o $perf_data ping -6 -c 1 ::1 > /dev/null 2>&1
  65         # check if perf data file got created in above step.
  66         if [ ! -e $perf_data ]; then
  67                 printf "FAIL: perf record failed to create \"%s\" \n" "$perf_data"
  68                 return 1
  69         fi
  70         perf script -i $perf_data | tac | grep -m1 ^ping -B9 | tac > $perf_script
  71
  72         exec 3<$perf_script
  73         exec 4<$expected
  74         while read line <&3 && read -r pattern <&4; do
  75                 [ -z "$pattern" ] && break
  76                 echo $line
  77                 echo "$line" | grep -E -q "$pattern"
  78                 if [ $? -ne 0 ] ; then
  79                         printf "FAIL: expected backtrace entry \"%s\" got \"%s\"\n" "$pattern" "$line"
  80                         return 1
  81                 fi
  82         done
  83
  84         # If any statements are executed from this point onwards,
  85         # the exit code of the last among these will be reflected
  86         # in err below. If the exit code is 0, the test will pass
  87         # even if the perf script output does not match.
  88 }
  89
  90 delete_libc_inet_pton_event() {
  91
  92         if [ -n "$event_name" ] ; then
  93                 perf probe -q -d $event_name
  94         fi
  95 }
  96
  97 # Check for IPv6 interface existence
  98 ip a sh lo | fgrep -q inet6 || exit 2
  99
 100 skip_if_no_perf_probe && \
 101 add_libc_inet_pton_event && \
 102 trace_libc_inet_pton_backtrace
 103 err=$?
 104 rm -f ${perf_data} ${perf_script} ${expected}
 105 delete_libc_inet_pton_event
 106 exit $err