On Sun, 25 Oct 2026 16:29:41 +0900, Jaewon Jung <[email protected]> wrote:
> Add a :debugfs requirement suffix to check interfaces under debugfs.
> Use it in the kprobe optimization test to report unsupported instead
> of failed when debugfs is unavailable.
>
> Tested on x86_64 with QEMU:
> - debugfs not mounted: UNSUPPORTED
> - debugfs mounted: PASS
>
> Signed-off-by: Jaewon Jung <[email protected]>
Good improvement! Let me pick it.
Thanks!
> ---
> tools/testing/selftests/ftrace/test.d/functions | 10 ++++++++++
> .../selftests/ftrace/test.d/kprobe/kprobe_opt_types.tc | 4 ++--
> tools/testing/selftests/ftrace/test.d/template | 1 +
> 3 files changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/ftrace/test.d/functions
> b/tools/testing/selftests/ftrace/test.d/functions
> index 826141e299e5..3cf8ac5fb4d4 100644
> --- a/tools/testing/selftests/ftrace/test.d/functions
> +++ b/tools/testing/selftests/ftrace/test.d/functions
> @@ -145,6 +145,7 @@ check_requires() { # Check required files and tracers
> p=${i%:program}
> r=${i%:README}
> t=${i%:tracer}
> + d=${i%:debugfs}
> if [ "$p" != "$i" ]; then
> if ! which "$p" ; then
> echo "Required program $p is not found."
> @@ -166,6 +167,15 @@ check_requires() { # Check required files and tracers
> echo "Required feature pattern \"$r\" is not in README."
> exit_unsupported
> fi
> + elif [ "$d" != "$i" ]; then
> + DEBUGFS_DIR=$(awk '$3 == "debugfs" { print $2; exit }' /proc/mounts)
> + if [ -z "$DEBUGFS_DIR" ]; then
> + echo "Required filesystem debugfs is not mounted."
> + exit_unsupported
> + elif [ ! -e "$DEBUGFS_DIR/$d" ]; then
> + echo "Required debugfs interface $d doesn't exist."
> + exit_unsupported
> + fi
> elif [ ! -e "$i" ]; then
> echo "Required feature interface $i doesn't exist."
> exit_unsupported
> diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_opt_types.tc
> b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_opt_types.tc
> index 9f5d99328086..25f7192f887b 100644
> --- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_opt_types.tc
> +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_opt_types.tc
> @@ -2,7 +2,7 @@
> # SPDX-License-Identifier: GPL-2.0-or-later
> # Copyright (C) 2023 Akanksha J N, IBM corporation
> # description: Register/unregister optimized probe
> -# requires: kprobe_events
> +# requires: kprobe_events kprobes/list:debugfs
>
> case `uname -m` in
> x86_64)
> @@ -22,7 +22,7 @@ for i in `seq 0 255`; do
> echo "p:testprobe $FUNCTION_FORK+${i}" > kprobe_events || continue
> echo 1 > events/kprobes/enable || continue
> (echo "forked")
> - PROBE=$(grep $FUNCTION_FORK /sys/kernel/debug/kprobes/list)
> + PROBE=$(grep $FUNCTION_FORK "$DEBUGFS_DIR/kprobes/list")
> echo 0 > events/kprobes/enable
> echo > kprobe_events
> if echo $PROBE | grep -q OPTIMIZED; then
> diff --git a/tools/testing/selftests/ftrace/test.d/template
> b/tools/testing/selftests/ftrace/test.d/template
> index 2cd8947edf72..d4a2500498f6 100644
> --- a/tools/testing/selftests/ftrace/test.d/template
> +++ b/tools/testing/selftests/ftrace/test.d/template
> @@ -5,6 +5,7 @@
> # The required tracer needs :tracer suffix, e.g. function:tracer
> # The required README string needs :README suffix, e.g. "x8/16/32/64":README
> # and the README string is treated as a fixed-string instead of regexp
> pattern.
> +# The required debugfs interface needs :debugfs suffix, e.g.
> kprobes/list:debugfs
> # you have to add ".tc" extention for your testcase file
> # Note that all tests are run with "errexit" option.
>
> --
> 2.43.0
>
>
--
Masami Hiramatsu (Google) <[email protected]>
