tools/perf/tests/shell/trace+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 $0)/lib/probe.sh
  12
  13 ld=$(realpath /lib64/ld*.so.* | uniq)
  14 libc=$(echo $ld | sed 's/ld/libc/g')
  15
  16 trace_libc_inet_pton_backtrace() {
  17         idx=0
  18         expected[0]="PING.*bytes"
  19         expected[1]="64 bytes from ::1.*"
  20         expected[2]=".*ping statistics.*"
  21         expected[3]=".*packets transmitted.*"
  22         expected[4]="rtt min.*"
  23         expected[5]="[0-9]+\.[0-9]+[[:space:]]+probe_libc:inet_pton:\([[:xdigit:]]+\)"
  24         expected[6]=".*inet_pton[[:space:]]\($libc|inlined\)$"
  25         case "$(uname -m)" in
  26         s390x)
  27                 eventattr='call-graph=dwarf'
  28                 expected[7]="gaih_inet.*[[:space:]]\($libc|inlined\)$"
  29                 expected[8]="__GI_getaddrinfo[[:space:]]\($libc|inlined\)$"
  30                 expected[9]="main[[:space:]]\(.*/bin/ping.*\)$"
  31                 expected[10]="__libc_start_main[[:space:]]\($libc\)$"
  32                 expected[11]="_start[[:space:]]\(.*/bin/ping.*\)$"
  33                 ;;
  34         *)
  35                 eventattr='max-stack=3'
  36                 expected[7]="getaddrinfo[[:space:]]\($libc\)$"
  37                 expected[8]=".*\(.*/bin/ping.*\)$"
  38                 ;;
  39         esac
  40
  41         perf trace --no-syscalls -e probe_libc:inet_pton/$eventattr/ ping -6 -c 1 ::1 2>&1 | grep -v ^$ | while read line ; do
  42                 echo $line
  43                 echo "$line" | egrep -q "${expected[$idx]}"
  44                 if [ $? -ne 0 ] ; then
  45                         printf "FAIL: expected backtrace entry %d \"%s\" got \"%s\"\n" $idx "${expected[$idx]}" "$line"
  46                         exit 1
  47                 fi
  48                 let idx+=1
  49                 [ -z "${expected[$idx]}" ] && break
  50         done
  51 }
  52
  53 skip_if_no_perf_probe && \
  54 perf probe -q $libc inet_pton && \
  55 trace_libc_inet_pton_backtrace
  56 err=$?
  57 rm -f ${file}
  58 perf probe -q -d probe_libc:inet_pton
  59 exit $err