4.18-stable review patch. If anyone has any objections, please let me know.
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From: Sandipan Das sandipan@linux.ibm.com
[ Upstream commit 60089e42d38438772e2f83334e3e5b7497009366 ]
If the event 'probe_libc:inet_pton' already exists, this test fails and deletes the existing event before exiting. This will then pass for any subsequent executions.
Instead of skipping to deleting the existing event because of failing to add a new event, a duplicate event is now created and the script continues with the usual checks. Only the new duplicate event that is created at the beginning of the test is deleted as a part of the cleanups in the end. All existing events remain as it is.
This can be observed on a powerpc64 system running Fedora 27 as shown below.
# perf probe -x /usr/lib64/power8/libc-2.26.so -a inet_pton
Added new event: probe_libc:inet_pton (on inet_pton in /usr/lib64/power8/libc-2.26.so)
Before:
# perf test -v "probe libc's inet_pton & backtrace it with ping"
62: probe libc's inet_pton & backtrace it with ping : --- start --- test child forked, pid 21302 test child finished with -1 ---- end ---- probe libc's inet_pton & backtrace it with ping: FAILED!
# perf probe --list
After:
# perf test -v "probe libc's inet_pton & backtrace it with ping"
62: probe libc's inet_pton & backtrace it with ping : --- start --- test child forked, pid 21490 ping 21513 [035] 39357.565561: probe_libc:inet_pton_1: (7fffa4c623b0) 7fffa4c623b0 __GI___inet_pton+0x0 (/usr/lib64/power8/libc-2.26.so) 7fffa4c190dc gaih_inet.constprop.7+0xf4c (/usr/lib64/power8/libc-2.26.so) 7fffa4c19c4c getaddrinfo+0x15c (/usr/lib64/power8/libc-2.26.so) 111d93c20 main+0x3e0 (/usr/bin/ping) test child finished with 0 ---- end ---- probe libc's inet_pton & backtrace it with ping: Ok
# perf probe --list
probe_libc:inet_pton (on __inet_pton@resolv/inet_pton.c in /usr/lib64/power8/libc-2.26.so)
Signed-off-by: Sandipan Das sandipan@linux.ibm.com Cc: Jiri Olsa jolsa@redhat.com Cc: Kim Phillips kim.phillips@arm.com Cc: Naveen N. Rao naveen.n.rao@linux.vnet.ibm.com Cc: Ravi Bangoria ravi.bangoria@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/e11fecff96e6cf4c65cdbd9012463513d7b8356c.1530724939... Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/perf/tests/shell/record+probe_libc_inet_pton.sh | 28 +++++++++++++++--- 1 file changed, 24 insertions(+), 4 deletions(-)
--- a/tools/perf/tests/shell/record+probe_libc_inet_pton.sh +++ b/tools/perf/tests/shell/record+probe_libc_inet_pton.sh @@ -13,11 +13,24 @@ libc=$(grep -w libc /proc/self/maps | head -1 | sed -r 's/.*[[:space:]](/.*)/\1/g') nm -Dg $libc 2>/dev/null | fgrep -q inet_pton || exit 254
+event_pattern='probe_libc:inet_pton(_[[:digit:]]+)?' + +add_libc_inet_pton_event() { + + event_name=$(perf probe -f -x $libc -a inet_pton 2>&1 | tail -n +2 | head -n -5 | \ + grep -P -o "$event_pattern(?=[[:space:]](on inet_pton in $libc))") + + if [ $? -ne 0 -o -z "$event_name" ] ; then + printf "FAIL: could not add event\n" + return 1 + fi +} + trace_libc_inet_pton_backtrace() {
expected=`mktemp -u /tmp/expected.XXX`
- echo "ping[][0-9 .:]+probe_libc:inet_pton: ([[:xdigit:]]+)" > $expected + echo "ping[][0-9 .:]+$event_name: ([[:xdigit:]]+)" > $expected echo ".*inet_pton+0x[[:xdigit:]]+[[:space:]]($libc|inlined)$" >> $expected case "$(uname -m)" in s390x) @@ -41,7 +54,7 @@ trace_libc_inet_pton_backtrace() {
perf_data=`mktemp -u /tmp/perf.data.XXX` perf_script=`mktemp -u /tmp/perf.script.XXX` - perf record -e probe_libc:inet_pton/$eventattr/ -o $perf_data ping -6 -c 1 ::1 > /dev/null 2>&1 + perf record -e $event_name/$eventattr/ -o $perf_data ping -6 -c 1 ::1 > /dev/null 2>&1 perf script -i $perf_data > $perf_script
exec 3<$perf_script @@ -62,13 +75,20 @@ trace_libc_inet_pton_backtrace() { # even if the perf script output does not match. }
+delete_libc_inet_pton_event() { + + if [ -n "$event_name" ] ; then + perf probe -q -d $event_name + fi +} + # Check for IPv6 interface existence ip a sh lo | fgrep -q inet6 || exit 2
skip_if_no_perf_probe && \ -perf probe -q $libc inet_pton && \ +add_libc_inet_pton_event && \ trace_libc_inet_pton_backtrace err=$? rm -f ${perf_data} ${perf_script} ${expected} -perf probe -q -d probe_libc:inet_pton +delete_libc_inet_pton_event exit $err