Commit c186ed12 authored Apr 02, 2024 by Pu Lehui Committed by Daniel Borkmann Apr 02, 2024

selftests/bpf: Skip test when perf_event_open returns EOPNOTSUPP



When testing send_signal and stacktrace_build_id_nmi using the riscv sbi
pmu driver without the sscofpmf extension or the riscv legacy pmu driver,
then failures as follows are encountered:

    test_send_signal_common:FAIL:perf_event_open unexpected perf_event_open: actual -1 < expected 0
    #272/3   send_signal/send_signal_nmi:FAIL

    test_stacktrace_build_id_nmi:FAIL:perf_event_open err -1 errno 95
    #304     stacktrace_build_id_nmi:FAIL

The reason is that the above pmu driver or hardware does not support
sampling events, that is, PERF_PMU_CAP_NO_INTERRUPT is set to pmu
capabilities, and then perf_event_open returns EOPNOTSUPP. Since
PERF_PMU_CAP_NO_INTERRUPT is not only set in the riscv-related pmu driver,
it is better to skip testing when this capability is set.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240402073029.1299085-1-pulehui@huaweicloud.com

parent 2a24e248

tools/testing/selftests/bpf/prog_tests/send_signal.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -179,7 +179,7 @@ static void test_send_signal_nmi(bool signal_thread)
		pmu_fd = syscall(__NR_perf_event_open, &attr, 0 /* pid */,
		-1 /* cpu /, -1 / group_fd /, 0 / flags */);
		if (pmu_fd == -1) {
		if (errno == ENOENT) {
		if (errno == ENOENT \|\| errno == EOPNOTSUPP) {
		printf("%s:SKIP:no PERF_COUNT_HW_CPU_CYCLES\n",
		__func__);
		test__skip();

tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -35,7 +35,7 @@ void test_stacktrace_build_id_nmi(void)
		pmu_fd = syscall(__NR_perf_event_open, &attr, -1 /* pid */,
		0 /* cpu 0 /, -1 / group id */,
		0 /* flags */);
		if (pmu_fd < 0 && errno == ENOENT) {
		if (pmu_fd < 0 && (errno == ENOENT \|\| errno == EOPNOTSUPP)) {
		printf("%s:SKIP:no PERF_COUNT_HW_CPU_CYCLES\n", __func__);
		test__skip();
		goto cleanup;