Re: [PATCH bpf-next 0/6] bpftool: Allow to select sections and filter probes

From: Michal Rostecki
Date: Wed Feb 19 2020 - 15:57:06 EST


On 2/19/20 5:52 PM, Daniel Borkmann wrote:
> On 2/19/20 5:37 PM, Alexei Starovoitov wrote:
>> On Wed, Feb 19, 2020 at 4:33 AM Michal Rostecki
>> <mrostecki@xxxxxxxxxxxx> wrote:
>>>
>>> On 2/19/20 4:02 AM, Alexei Starovoitov wrote:
>>>> The motivation is clear, but I think the users shouldn't be made
>>>> aware of such implementation details. I think instead of filter_in/out
>>>> it's better to do 'full or safe' mode of probing.
>>>> By default it can do all the probing that doesn't cause
>>>> extra dmesgs and in 'full' mode it can probe everything.
>>>
>>> Alright, then I will send later v2 where the "internal" implementation
>>> (filtering out based on regex) stays similar (filter_out will stay in
>>> the code without being exposed to users, filter_in will be removed). And
>>> the exposed option of "safe" probing will just apply the
>>> "(trace|write_user)" filter_out pattern. Does it sound good?
>>
>> yes. If implementation is doing filter_in and applying
>> 'trace_printk|write_user'
>> strings hidden within bpftool than I think it should be good.
>> What do you think the default should be?
>> It feels to me that the default should not be causing dmesg prints.
>> So only addition flag for bpftool command line will be 'bpftool
>> feature probe full'
>
> Agree, that makes sense to me.

Makes sense to me as well. I will do that in v2.