Re: [PATCH bpf-next v6 3/3] selftests/bpf: Add cases to test tailcall in freplace

[Leon Hwang <leon.hwang@linux.dev>]

On 10/10/24 08:59, Alexei Starovoitov wrote:
> On Tue, Oct 8, 2024 at 11:05 PM Leon Hwang <leon.hwang@linux.dev> wrote:
>>
>>
>>
>> On 9/10/24 13:04, Eduard Zingerman wrote:
>>> On Wed, 2024-10-09 at 00:13 +0800, Leon Hwang wrote:
>>>> cd tools/testing/selftests/bpf; ./test_progs -t tailcalls
>>>> 335/27  tailcalls/tailcall_bpf2bpf_hierarchy_freplace_1:OK
>>>> 335/28  tailcalls/tailcall_bpf2bpf_hierarchy_freplace_2:OK
>>>> 335     tailcalls:OK
>>>> Summary: 1/28 PASSED, 0 SKIPPED, 0 FAILED
>>>>
>>>> Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
>>>> ---
>>>
>>> Tbh, I don't think these tests are necessary.
>>> Patch #2 already covers changes in patch #1.
>>>
>>> [...]
>>>
>>
>> You are right.
>>
>> I should provide the commit message to tell the reason why to add these
>> two test cases:
>>
>> In order to confirm tailcall in freplace is OK and won't be broken by
>> patch of preventing tailcall infinite loop caused by freplace or other
>> patches in the future, add two test cases to confirm that freplace is OK
>> to tail call itself or other freplace prog, even if the target prog of
>> freplace is a subprog and the subprog is called many times in its caller.
> 
> Not following.
> What's the point of adding more tests when patch 2 covers the cases already?

It's to test cases about tailcall in freplace.

But it seems unnecessary to add them. I'll drop this patch.

Thanks,
Leon