Re: [PATCH v2] perf test: Fix inet_pton probe failure and unroll call graph

[sashiko-bot@kernel.org]

Sashiko AI review found 1 potential issue(s):
- [Medium] Unconditionally requiring DWARF call-graphs causes the test to falsely fail on perf builds lacking DWARF support.
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commit dbec7073d294917f7866e8ea3a6b39004a7407ad
Author: Ian Rogers <irogers@google.com>

perf test: Fix inet_pton probe failure and unroll call graph

This commit fixes an issue where multiple identical event names were output
by perf probe when creating multiple probe points, which broke subsequent
commands. It also updates the backtrace collection to explicitly request
dwarf call-graphs and increases max-stack to 8 for all architectures.

> 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 ab99bef556bf0..eca629ee83f03 100755
> --- a/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
> +++ b/tools/perf/tests/shell/record+probe_libc_inet_pton.sh
[ ... ]
> @@ -40,12 +40,12 @@ trace_libc_inet_pton_backtrace() {
>  	echo ".*inet_pton\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
>  	case "$(uname -m)" in
>  	s390x)
> -		eventattr='call-graph=dwarf,max-stack=4'
> +		eventattr='call-graph=dwarf,max-stack=8'
>  		echo "((__GI_)?getaddrinfo|text_to_binary_address)\+0x[[:xdigit:]]+[[:space:]]\($libc|inlined\)$" >> $expected
>  		echo "(gaih_inet|main)\+0x[[:xdigit:]]+[[:space:]]\(inlined|.*/bin/ping.*\)$" >> $expected
>  		;;
>  	*)
> -		eventattr='max-stack=4'
> +		eventattr='call-graph=dwarf,max-stack=8'

Will this cause the test to falsely fail on perf builds lacking DWARF support?

If perf is compiled without libunwind or libdw, running perf record with
call-graph=dwarf will exit with an error. Since the test script doesn't
appear to verify DWARF support before running, the test will report a hard
failure rather than gracefully skipping on minimal perf builds.

>  		echo ".*(\+0x[[:xdigit:]]+|\[unknown\])[[:space:]]\(.*/bin/ping.*\)$" >> $expected
>  		;;
>  	esac

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Sashiko AI review · https://sashiko.dev/#/patchset/20260411193705.735269-1-irogers@google.com?part=1