[RFC v1 04/14] krsi: Add support in libbpf for BPF_PROG_TYPE_KRSI

[Yonghong Song]

On 9/10/19 12:55 PM, KP Singh wrote:
> From: KP Singh <kpsingh at google.com>
> 
> Update the libbpf library with functionality to load and
> attach a program type BPF_PROG_TYPE_KRSI.
> 
> Since the bpf_prog_load does not allow the specification of an
> expected attach type, it's recommended to use bpf_prog_load_xattr and
> set the expected attach type as KRSI.
> 
> Signed-off-by: KP Singh <kpsingh at google.com>
> ---
>   tools/lib/bpf/libbpf.c        | 4 ++++
>   tools/lib/bpf/libbpf.h        | 2 ++
>   tools/lib/bpf/libbpf.map      | 2 ++
>   tools/lib/bpf/libbpf_probes.c | 1 +
>   4 files changed, 9 insertions(+)
> 
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 2b57d7ea7836..3cc86bbc68cd 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -2676,6 +2676,7 @@ static bool bpf_prog_type__needs_kver(enum bpf_prog_type type)
>   	case BPF_PROG_TYPE_PERF_EVENT:
>   	case BPF_PROG_TYPE_CGROUP_SYSCTL:
>   	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
> +	case BPF_PROG_TYPE_KRSI:
>   		return false;
>   	case BPF_PROG_TYPE_KPROBE:
>   	default:
> @@ -3536,6 +3537,7 @@ bool bpf_program__is_##NAME(const struct bpf_program *prog)	\
>   }								\
>   
>   BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER);
> +BPF_PROG_TYPE_FNS(krsi, BPF_PROG_TYPE_KRSI);
>   BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE);
>   BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS);
>   BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT);
> @@ -3590,6 +3592,8 @@ static const struct {
>   	BPF_PROG_SEC("lwt_out",			BPF_PROG_TYPE_LWT_OUT),
>   	BPF_PROG_SEC("lwt_xmit",		BPF_PROG_TYPE_LWT_XMIT),
>   	BPF_PROG_SEC("lwt_seg6local",		BPF_PROG_TYPE_LWT_SEG6LOCAL),
> +	BPF_APROG_SEC("krsi",			BPF_PROG_TYPE_KRSI,
> +						BPF_KRSI),
>   	BPF_APROG_SEC("cgroup_skb/ingress",	BPF_PROG_TYPE_CGROUP_SKB,
>   						BPF_CGROUP_INET_INGRESS),
>   	BPF_APROG_SEC("cgroup_skb/egress",	BPF_PROG_TYPE_CGROUP_SKB,
> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
> index 5cbf459ece0b..8781d29b4035 100644
> --- a/tools/lib/bpf/libbpf.h
> +++ b/tools/lib/bpf/libbpf.h
> @@ -261,6 +261,7 @@ LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
>   LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
>   LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
>   LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
> +LIBBPF_API int bpf_program__set_krsi(struct bpf_program *prog);
>   LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
>   				      enum bpf_prog_type type);
>   LIBBPF_API void
> @@ -275,6 +276,7 @@ LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
>   LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
>   LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
>   LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
> +LIBBPF_API bool bpf_program__is_krsi(const struct bpf_program *prog);
>   
>   /*
>    * No need for __attribute__((packed)), all members of 'bpf_map_def'
> diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
> index f9d316e873d8..75b8fe419c11 100644
> --- a/tools/lib/bpf/libbpf.map
> +++ b/tools/lib/bpf/libbpf.map
> @@ -68,6 +68,7 @@ LIBBPF_0.0.1 {
>   		bpf_prog_test_run_xattr;
>   		bpf_program__fd;
>   		bpf_program__is_kprobe;
> +		bpf_program__is_krsi;
>   		bpf_program__is_perf_event;
>   		bpf_program__is_raw_tracepoint;
>   		bpf_program__is_sched_act;
> @@ -85,6 +86,7 @@ LIBBPF_0.0.1 {
>   		bpf_program__set_expected_attach_type;
>   		bpf_program__set_ifindex;
>   		bpf_program__set_kprobe;
> +		bpf_program__set_krsi;
>   		bpf_program__set_perf_event;
>   		bpf_program__set_prep;
>   		bpf_program__set_priv;

Please put the above two new API functions in version LIBBPF_0.0.5.

> diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
> index ace1a0708d99..cc515a36794d 100644
> --- a/tools/lib/bpf/libbpf_probes.c
> +++ b/tools/lib/bpf/libbpf_probes.c
> @@ -102,6 +102,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
>   	case BPF_PROG_TYPE_FLOW_DISSECTOR:
>   	case BPF_PROG_TYPE_CGROUP_SYSCTL:
>   	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
> +	case BPF_PROG_TYPE_KRSI:
>   	default:
>   		break;
>   	}
>