2022-03-10 13:18 UTC+0100 ~ Niklas Söderlund <niklas.soderlund@xxxxxxxxxxxx>
> Commit 1a56c18e6c2e4e74 ("bpftool: Stop supporting BPF offload-enabled
> feature probing") removed the support to probe for BPF offload features.
> This is still something that is useful for NFP NIC that can support
> offloading of BPF programs.
>
> The reason for the dropped support was that libbpf starting with v1.0
> would drop support for passing the ifindex to the BPF prog/map/helper
> feature probing APIs. In order to keep this useful feature for NFP
> restore the functionality by moving it directly into bpftool.
>
> The code restored is a simplified version of the code that existed in
> libbpf which supposed passing the ifindex. The simplification is that it
> only targets the cases where ifindex is given and call into libbpf for
> the cases where it's not.
>
> Before restoring support for probing offload features:
>
> # bpftool feature probe dev ens4np0
> Scanning system call availability...
> bpf() syscall is available
>
> Scanning eBPF program types...
>
> Scanning eBPF map types...
>
> Scanning eBPF helper functions...
> eBPF helpers supported for program type sched_cls:
> eBPF helpers supported for program type xdp:
>
> Scanning miscellaneous eBPF features...
> Large program size limit is NOT available
> Bounded loop support is NOT available
> ISA extension v2 is NOT available
> ISA extension v3 is NOT available
>
> With support for probing offload features restored:
>
> # bpftool feature probe dev ens4np0
> Scanning system call availability...
> bpf() syscall is available
>
> Scanning eBPF program types...
> eBPF program_type sched_cls is available
> eBPF program_type xdp is available
>
> Scanning eBPF map types...
> eBPF map_type hash is available
> eBPF map_type array is available
>
> Scanning eBPF helper functions...
> eBPF helpers supported for program type sched_cls:
> - bpf_map_lookup_elem
> - bpf_get_prandom_u32
> - bpf_perf_event_output
> eBPF helpers supported for program type xdp:
> - bpf_map_lookup_elem
> - bpf_get_prandom_u32
> - bpf_perf_event_output
> - bpf_xdp_adjust_head
> - bpf_xdp_adjust_tail
>
> Scanning miscellaneous eBPF features...
> Large program size limit is NOT available
> Bounded loop support is NOT available
> ISA extension v2 is NOT available
> ISA extension v3 is NOT available
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund@xxxxxxxxxxxx>
> Signed-off-by: Simon Horman <simon.horman@xxxxxxxxxxxx>
Looks good to me, thank you!
Reviewed-by: Quentin Monnet <quentin@xxxxxxxxxxxxx>
