[PATCH] perf tests: Fix record+probe_libc_inet_pton.sh for powerpc64

[Seeteena Thoufeek <s1seetee@linux.vnet.ibm.com>]

'probe libc's inet_pton & backtrace it with ping' testcase sometimes
fails on powerpc because distro ping binary does not have symbol
information and thus it prints "[unknown]" function name in the
backtrace.

Accept "[unknown]" as valid function name for powerpc as well.

 # perf test -v "probe libc's inet_pton & backtrace it with ping"

Before:

  59: probe libc's inet_pton & backtrace it with ping       :
  --- start ---
  test child forked, pid 79695
  ping 79718 [077] 96483.787025: probe_libc:inet_pton: (7fff83a754c8)
  7fff83a754c8 __GI___inet_pton+0x8 (/usr/lib64/power9/libc-2.28.so)
  7fff83a2b7a0 gaih_inet.constprop.7+0x1020
  (/usr/lib64/power9/libc-2.28.so)
  7fff83a2c170 getaddrinfo+0x160 (/usr/lib64/power9/libc-2.28.so)
  1171830f4 [unknown] (/usr/bin/ping)
  FAIL: expected backtrace entry
  ".*\+0x[[:xdigit:]]+[[:space:]]\(.*/bin/ping.*\)$"
  got "1171830f4 [unknown] (/usr/bin/ping)"
  test child finished with -1
  ---- end ----
  probe libc's inet_pton & backtrace it with ping: FAILED!

After:

  59: probe libc's inet_pton & backtrace it with ping       :
  --- start ---
  test child forked, pid 79085
  ping 79108 [045] 96400.214177: probe_libc:inet_pton: (7fffbb9654c8)
  7fffbb9654c8 __GI___inet_pton+0x8 (/usr/lib64/power9/libc-2.28.so)
  7fffbb91b7a0 gaih_inet.constprop.7+0x1020
  (/usr/lib64/power9/libc-2.28.so)
  7fffbb91c170 getaddrinfo+0x160 (/usr/lib64/power9/libc-2.28.so)
  132e830f4 [unknown] (/usr/bin/ping)
  test child finished with 0
  ---- end ----
  probe libc's inet_pton & backtrace it with ping: Ok

Signed-off-by: Seeteena Thoufeek <s1seetee@linux.vnet.ibm.com>
---
 tools/perf/tests/shell/record+probe_libc_inet_pton.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/tests/shell/record+probe_libc_inet_pton.sh b/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
index 61c9f8f..58a99a2 100755
--- a/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
+++ b/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
@@ -44,7 +44,7 @@ trace_libc_inet_pton_backtrace() {
 		eventattr='max-stack=4'
 		echo "gaih_inet.*\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
 		echo "getaddrinfo\+0x[[:xdigit:]]+[[:space:]]\($libc\)$" >> $expected
-		echo ".*\+0x[[:xdigit:]]+[[:space:]]\(.*/bin/ping.*\)$" >> $expected
+		echo ".*(\+0x[[:xdigit:]]+|\[unknown\])[[:space:]]\(.*/bin/ping.*\)$" >> $expected
 		;;
 	*)
 		eventattr='max-stack=3'
-- 
1.8.3.1