Em Thu, Jun 07, 2018 at 01:07:01PM -0700, Martin KaFai Lau escreveu:
> On Thu, Jun 07, 2018 at 04:30:29PM -0300, Arnaldo Carvalho de Melo wrote:
> > So this must be available in a newer llvm version? Which one?
> I should have put in the details in my last email or
> in the commit message, my bad.
> 1. The tools/testing/selftests/bpf/Makefile has the CLANG_FLAGS and
> LLC_FLAGS needed to compile the bpf prog. It requires a new
> "-mattr=dwarf" llc option which was added to the future
> llvm 7.0.
> Hence, I have been using the llvm's master in github which
> also has the llvm-objcopy.
> 2. The kernel's btf part only focus on the BPF map.
> Hence, the testing bpf program should have the map's key
> and map's value. e.g. tools/testing/selftests/bpf/test_btf_haskv.c
Thanks for the version required to test this, but where is this
test_btf_haskv.c file? Which tree? net-next?
Ok, just pulled torvalds/master and there it is. Gotcha.
struct bpf_map_def SEC("maps") __bpf_stdout__ = {
.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(u32),
.max_entries = __NR_CPUS__,
};
This map is in the above hello.c example, but I guess its way too simple
:-)
Ok, I'll test this at home in another machine where I have the llvm's
git repo.
- Arnaldo
