[PATCH v1] perf test: Fix inet_pton probe failure due to multiple probes

[Ian Rogers <irogers@google.com>]

When adding a probe for libc's inet_pton, perf probe may create multiple
probe points (e.g., due to inlining or multiple symbol resolutions),
resulting in multiple identical event names being output (e.g.,
`probe_libc:inet_pton_1`).

The script previously used a brittle pipeline (`tail -n +2 | head -n -5`)
and an awk script to extract the event name. When multiple probes were
added, awk would output the event name multiple times, which expanded
to multiple words in bash. This broke the subsequent `perf record` and
`perf probe -d` commands, causing the test to fail with:
`Error: another command except --add is set.`

Fix this by removing the brittle `tail/head` commands and appending
`| sort -u` to the awk extraction. This ensures that only a single,
unique event name is captured, regardless of how many probe points
are created.

Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/shell/record+probe_libc_inet_pton.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

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 ab99bef556bf..b717063f70c2 100755
--- a/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
+++ b/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
@@ -22,9 +22,9 @@ event_pattern='probe_libc:inet_pton(_[[:digit:]]+)?'
 
 add_libc_inet_pton_event() {
 
-	event_name=$(perf probe -f -x $libc -a inet_pton 2>&1 | tail -n +2 | head -n -5 | \
+	event_name=$(perf probe -f -x $libc -a inet_pton 2>&1 | \
 			awk -v ep="$event_pattern" -v l="$libc" '$0 ~ ep && $0 ~ \
-			("\\(on inet_pton in " l "\\)") {print $1}')
+			("\\(on inet_pton in " l "\\)") {print $1}' | sort -u)
 
 	if [ $? -ne 0 ] || [ -z "$event_name" ] ; then
 		printf "FAIL: could not add event\n"
-- 
2.53.0.1213.gd9a14994de-goog