Re: [PATCH bpf-next 14/17] libbpf: Add support for SK_LOOKUP program type

From: Yonghong Song <yhs@fb.com>
To: Andrii Nakryiko <andrii.nakryiko@gmail.com>,
	Jakub Sitnicki <jakub@cloudflare.com>
Cc: Networking <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>,
	<dccp@vger.kernel.org>, <kernel-team@cloudflare.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Gerrit Renker <gerrit@erg.abdn.ac.uk>,
	Jakub Kicinski <kuba@kernel.org>
Subject: Re: [PATCH bpf-next 14/17] libbpf: Add support for SK_LOOKUP program type
Date: Fri, 8 May 2020 10:52:33 -0700	[thread overview]
Message-ID: <c3eb3e32-237f-af0b-69b4-3233ab65490c@fb.com> (raw)
In-Reply-To: <CAEf4BzaE=+0ZkwqetjDHg4MnE1WDQDKFHqEkM825h6YMCZAdNA@mail.gmail.com>

On 5/8/20 10:41 AM, Andrii Nakryiko wrote:
> On Wed, May 6, 2020 at 5:58 AM Jakub Sitnicki <jakub@cloudflare.com> wrote:
>>
>> Make libbpf aware of the newly added program type, and assign it a
>> section name.
>>
>> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
>> ---
>>   tools/lib/bpf/libbpf.c        | 3 +++
>>   tools/lib/bpf/libbpf.h        | 2 ++
>>   tools/lib/bpf/libbpf.map      | 2 ++
>>   tools/lib/bpf/libbpf_probes.c | 1 +
>>   4 files changed, 8 insertions(+)
>>
>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
>> index 977add1b73e2..74f4a15dc19e 100644
>> --- a/tools/lib/bpf/libbpf.c
>> +++ b/tools/lib/bpf/libbpf.c
>> @@ -6524,6 +6524,7 @@ BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
>>   BPF_PROG_TYPE_FNS(tracing, BPF_PROG_TYPE_TRACING);
>>   BPF_PROG_TYPE_FNS(struct_ops, BPF_PROG_TYPE_STRUCT_OPS);
>>   BPF_PROG_TYPE_FNS(extension, BPF_PROG_TYPE_EXT);
>> +BPF_PROG_TYPE_FNS(sk_lookup, BPF_PROG_TYPE_SK_LOOKUP);
>>
>>   enum bpf_attach_type
>>   bpf_program__get_expected_attach_type(struct bpf_program *prog)
>> @@ -6684,6 +6685,8 @@ static const struct bpf_sec_def section_defs[] = {
>>          BPF_EAPROG_SEC("cgroup/setsockopt",     BPF_PROG_TYPE_CGROUP_SOCKOPT,
>>                                                  BPF_CGROUP_SETSOCKOPT),
>>          BPF_PROG_SEC("struct_ops",              BPF_PROG_TYPE_STRUCT_OPS),
>> +       BPF_EAPROG_SEC("sk_lookup",             BPF_PROG_TYPE_SK_LOOKUP,
>> +                                               BPF_SK_LOOKUP),
>>   };
>>
>>   #undef BPF_PROG_SEC_IMPL
>> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
>> index f1dacecb1619..8373fbacbba3 100644
>> --- a/tools/lib/bpf/libbpf.h
>> +++ b/tools/lib/bpf/libbpf.h
>> @@ -337,6 +337,7 @@ LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
>>   LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
>>   LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
>>   LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
>> +LIBBPF_API int bpf_program__set_sk_lookup(struct bpf_program *prog);
>>
>>   LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
>>   LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
>> @@ -364,6 +365,7 @@ LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
>>   LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
>>   LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
>>   LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
>> +LIBBPF_API bool bpf_program__is_sk_lookup(const struct bpf_program *prog);
> 
> cc Yonghong, bpf_iter programs should probably have similar
> is_xxx/set_xxx functions?..

Not sure about this. bpf_iter programs have prog type TRACING
which is covered by the above bpf_program__is_tracing.

> 
>>
>>   /*
>>    * 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 e03bd4db827e..113ac0a669c2 100644
>> --- a/tools/lib/bpf/libbpf.map
>> +++ b/tools/lib/bpf/libbpf.map
>> @@ -253,6 +253,8 @@ LIBBPF_0.0.8 {
>>                  bpf_program__set_attach_target;
>>                  bpf_program__set_lsm;
>>                  bpf_set_link_xdp_fd_opts;
>> +               bpf_program__is_sk_lookup;
>> +               bpf_program__set_sk_lookup;
>>   } LIBBPF_0.0.7;
>>
> 
> 0.0.8 is sealed, please add them into 0.0.9 map below
> 
>>   LIBBPF_0.0.9 {
>> diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
>> index 2c92059c0c90..5c6d3e49f254 100644
>> --- a/tools/lib/bpf/libbpf_probes.c
>> +++ b/tools/lib/bpf/libbpf_probes.c
>> @@ -109,6 +109,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
>>          case BPF_PROG_TYPE_STRUCT_OPS:
>>          case BPF_PROG_TYPE_EXT:
>>          case BPF_PROG_TYPE_LSM:
>> +       case BPF_PROG_TYPE_SK_LOOKUP:
>>          default:
>>                  break;
>>          }
>> --
>> 2.25.3
>>