On Thu, Oct 17, 2019 at 9:28 AM Stanislav Fomichev <sdf@xxxxxxxxxxx> wrote:
> Tried to do the following:
>
> 1. Add: static volatile const char __annotate_source1[] = __FILE__;
> to test_rdonly_maps.c and I think it got optimized away :-/
> At least I don't see it in the 'bpftool btf dump' output.
>
> 2. Add: char __annotate_source2[] SEC(".meta") = __FILE__;
> to test_rdonly_maps.c and do all the required plumbing in libbpf
> to treat .meta like .rodata. I think it works, but the map
> disappears after bpftool exits because this data is not referenced
> in the prog and the refcount drops to zero :-(
>
> Am I missing something?
"Some assembly required".
I think first variant should work at the end.
I don't think extra section should be a requirement.
Sounds like with 2 it's pretty close. Just need to make sure
that prog side sees the map as referenced.
And more importantly bpftool can find that map from prog later.
