From: Masami Hiramatsu (Google) <[email protected]> Add a selftest for trace probe BPF compilation to verify that BPF is correctly compiled and executes properly for valid configurations, and falls back to interpreter on unsupported cases.
Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu <[email protected]> --- .../ftrace/test.d/dynevent/test_bpf_fetchargs.tc | 51 ++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/test_bpf_fetchargs.tc diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/test_bpf_fetchargs.tc b/tools/testing/selftests/ftrace/test.d/dynevent/test_bpf_fetchargs.tc new file mode 100644 index 000000000000..6c6f4dd4517a --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/dynevent/test_bpf_fetchargs.tc @@ -0,0 +1,51 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Dynamic event - test eBPF compiled fetchargs for tprobe and fprobe +# requires: dynamic_events "t[:[<group>/][<event>]] <tracepoint> [<args>]":README + +# Check if the sample module is loaded +if ! lsmod | grep -q trace_events_sample; then + modprobe trace-events-sample || exit_unsupported +fi + +echo 0 > events/enable +echo > dynamic_events +clear_trace + +# Add a tprobe to sample-trace:foo_bar +# foo_bar args: const char *foo, int bar, ... +# So $arg1 is char ptr (points to "hello"), $arg2 is int. +# Let's test REG (arg2) and DEREF (+0($arg1)) +# "hello" in little-endian 32-bit: 'h'(0x68), 'e'(0x65), 'l'(0x6c), 'l'(0x6c) -> 0x6c6c6568 -> 1819043176 +echo "t:test_tprobe foo_bar mybar=\$arg2 myfoo=+0(\$arg1):u32" >> dynamic_events + +# Add an fprobe to __traceiter_foo_bar +if grep -q "__traceiter_foo_bar" /proc/kallsyms; then + # __traceiter_foo_bar args: void *__data, const char *foo, int bar, ... + # $arg1 is __data, $arg2 is foo (points to "hello") + # "hello" in little-endian 32-bit: 'h'(0x68), 'e'(0x65), 'l'(0x6c), 'l'(0x6c) -> 0x6c6c6568 -> 1819043176 + echo "f:test_fprobe __traceiter_foo_bar myfoo=\$arg2 myfmt=+0(\$arg2):u32" >> dynamic_events +fi + +echo 1 > events/sample-trace/foo_bar/enable +echo 1 > events/tracepoints/test_tprobe/enable +if [ -d events/fprobes/test_fprobe ]; then + echo 1 > events/fprobes/test_fprobe/enable +fi + +# Wait for 2 seconds to let the sample thread trigger the events +sleep 2 + +echo 0 > events/enable + +# Now verify the trace +grep -q "test_tprobe.*myfoo=1819043176" trace || exit_fail + +if [ -d events/fprobes/test_fprobe ]; then + grep -q "test_fprobe.*myfmt=1819043176" trace || exit_fail +fi + +echo > dynamic_events +rmmod trace-events-sample + +exit 0
