Re: [PATCH bpf-next v3 3/3] selftests/bpf: Add libbpf_probe_bpf_kfunc API selftests

[Tao Chen <chen.dylane@gmail.com>]

在 2025/1/25 00:27, Jiri Olsa 写道:
> On Fri, Jan 24, 2025 at 10:44:11PM +0800, Tao Chen wrote:
>> Add selftests for prog_kfunc feature probing.
>>   ./test_progs -t libbpf_probe_kfuncs
>>   #153     libbpf_probe_kfuncs:OK
>>   Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
>>
>> Signed-off-by: Tao Chen <chen.dylane@gmail.com>
>> ---
>>   .../selftests/bpf/prog_tests/libbpf_probes.c  | 35 +++++++++++++++++++
>>   1 file changed, 35 insertions(+)
>>
>> diff --git a/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c b/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c
>> index 4ed46ed58a7b..d9d69941f694 100644
>> --- a/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c
>> +++ b/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c
>> @@ -126,3 +126,38 @@ void test_libbpf_probe_helpers(void)
>>   		ASSERT_EQ(res, d->supported, buf);
>>   	}
>>   }
>> +
>> +void test_libbpf_probe_kfuncs(void)
>> +{
>> +	int ret, kfunc_id;
>> +	char *kfunc = "bpf_cpumask_create";
>> +	struct btf *btf;
>> +
>> +	btf = btf__parse("/sys/kernel/btf/vmlinux", NULL);
>> +	if (!ASSERT_OK_PTR(btf, "btf_parse"))
>> +		return;
>> +
>> +	kfunc_id = btf__find_by_name_kind(btf, kfunc, BTF_KIND_FUNC);
>> +	if (!ASSERT_GT(kfunc_id, 0, kfunc))
>> +		goto cleanup;
>> +
>> +	/* prog BPF_PROG_TYPE_SYSCALL supports kfunc bpf_cpumask_create */
>> +	ret = libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_SYSCALL, kfunc_id, 0, NULL);
>> +	ASSERT_EQ(ret, 1, kfunc);
>> +
>> +	/* prog BPF_PROG_TYPE_KPROBE does not support kfunc bpf_cpumask_create */
>> +	ret = libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_KPROBE, kfunc_id, 0, NULL);
>> +	ASSERT_EQ(ret, 0, kfunc);
>> +
>> +	/* invalid kfunc id */
>> +	ret = libbpf_probe_bpf_kfunc(BPF_PROG_TYPE_KPROBE, -1, 0, NULL);
>> +	ASSERT_EQ(ret, 0, "invalid kfunc id:-1");
>> +
>> +	/* invalid prog type */
>> +	ret = libbpf_probe_bpf_kfunc(100000, kfunc_id, 0, NULL);
>> +	if (!ASSERT_LE(ret, 0, "invalid prog type:100000"))
>> +		goto cleanup;
> 
> nit no need for the goto
> 
> jirka
> 

Ack. Will fix.

>> +
>> +cleanup:
>> +	btf__free(btf);
>> +}
>> -- 
>> 2.43.0
>>


-- 
Best Regards
Dylane Chen