Re: libbpf: pinning multiple progs from the same section

["Toke Høiland-Jørgensen" <toke@redhat.com>]

Gilad Reti <gilad.reti@gmail.com> writes:

>> > I didn't get this last comment. What I meant is that I want something
>> > like the bpf_object__pin_maps but that doesn't pin the maps, just
>> > exposing its naming part.
>>
>> Right, OK. Why, though? I can kinda see how it could be convenient to
>> (basically )make libbpf behave as if all maps has the 'pinning'
>> attribute set, for map reuse. But I'm not sure I can think any concrete
>> use cases where this would be needed. What's yours?
>>
>
> I am using the same bpf objects (more specifically, the new skeleton
> feature) in two different processes that need access to the same
> maps/programs (for example, they both need access to shared maps).
> Thus, I want to reuse the entire object in both. Since we already have
> a way to pin an entire bpf object, I thought it would be convenient to
> have a way of reusing it entirely (though I am fine with pinning and
> reusing each one manually).
> (I cannot set the __uint(pinning, LIBBPF_PIN_BY_NAME) on each since I
> want to share the bss map too)

Ah, see, now *this* could go under the "missing API" header: having a
way to make libbpf pin (and reuse) the auto-generated maps, like you can
do with the 'pinning' attribute.

Andrii, WDYT?

-Toke