From: Jiri Olsa <jolsa@redhat.com>
To: Yonghong Song <yhs@fb.com>
Cc: Jiri Olsa <jolsa@kernel.org>, Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Andrii Nakryiko <andriin@fb.com>,
"Steven Rostedt (VMware)" <rostedt@goodmis.org>,
netdev@vger.kernel.org, bpf@vger.kernel.org,
Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
John Fastabend <john.fastabend@gmail.com>,
KP Singh <kpsingh@chromium.org>, Daniel Xu <dxu@dxuuu.xyz>,
Viktor Malik <vmalik@redhat.com>
Subject: Re: [PATCH 15/19] libbpf: Add support to link multi func tracing program
Date: Mon, 7 Jun 2021 20:28:48 +0200 [thread overview]
Message-ID: <YL5lYPJdx5mmd06F@krava> (raw)
In-Reply-To: <50f92d1e-1138-656c-4318-8fecf61f2025@fb.com>
On Sun, Jun 06, 2021 at 10:49:16PM -0700, Yonghong Song wrote:
>
>
> On 6/5/21 4:10 AM, Jiri Olsa wrote:
> > Adding support to link multi func tracing program
> > through link_create interface.
> >
> > Adding special types for multi func programs:
> >
> > fentry.multi
> > fexit.multi
> >
> > so you can define multi func programs like:
> >
> > SEC("fentry.multi/bpf_fentry_test*")
> > int BPF_PROG(test1, unsigned long ip, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f)
> >
> > that defines test1 to be attached to bpf_fentry_test* functions,
> > and able to attach ip and 6 arguments.
> >
> > If functions are not specified the program needs to be attached
> > manually.
> >
> > Adding new btf id related fields to bpf_link_create_opts and
> > bpf_link_create to use them.
> >
> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> > ---
> > tools/lib/bpf/bpf.c | 11 ++++++-
> > tools/lib/bpf/bpf.h | 4 ++-
> > tools/lib/bpf/libbpf.c | 72 ++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 85 insertions(+), 2 deletions(-)
> >
> > diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> > index 86dcac44f32f..da892737b522 100644
> > --- a/tools/lib/bpf/bpf.c
> > +++ b/tools/lib/bpf/bpf.c
> > @@ -674,7 +674,8 @@ int bpf_link_create(int prog_fd, int target_fd,
> > enum bpf_attach_type attach_type,
> > const struct bpf_link_create_opts *opts)
> > {
> > - __u32 target_btf_id, iter_info_len;
> > + __u32 target_btf_id, iter_info_len, multi_btf_ids_cnt;
> > + __s32 *multi_btf_ids;
> > union bpf_attr attr;
> > int fd;
> [...]
> > @@ -9584,6 +9597,9 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog, int *btf_obj_fd,
> > if (!name)
> > return -EINVAL;
> > + if (prog->prog_flags & BPF_F_MULTI_FUNC)
> > + return 0;
> > +
> > for (i = 0; i < ARRAY_SIZE(section_defs); i++) {
> > if (!section_defs[i].is_attach_btf)
> > continue;
> > @@ -10537,6 +10553,62 @@ static struct bpf_link *bpf_program__attach_btf_id(struct bpf_program *prog)
> > return (struct bpf_link *)link;
> > }
> > +static struct bpf_link *bpf_program__attach_multi(struct bpf_program *prog)
> > +{
> > + char *pattern = prog->sec_name + prog->sec_def->len;
> > + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
> > + enum bpf_attach_type attach_type;
> > + int prog_fd, link_fd, cnt, err;
> > + struct bpf_link *link = NULL;
> > + __s32 *ids = NULL;
> > +
> > + prog_fd = bpf_program__fd(prog);
> > + if (prog_fd < 0) {
> > + pr_warn("prog '%s': can't attach before loaded\n", prog->name);
> > + return ERR_PTR(-EINVAL);
> > + }
> > +
> > + err = bpf_object__load_vmlinux_btf(prog->obj, true);
> > + if (err)
> > + return ERR_PTR(err);
> > +
> > + cnt = btf__find_by_pattern_kind(prog->obj->btf_vmlinux, pattern,
> > + BTF_KIND_FUNC, &ids);
> > + if (cnt <= 0)
> > + return ERR_PTR(-EINVAL);
>
> In kernel, looks like we support cnt = 0, here we error out.
> Should we also error out in the kernel if cnt == 0?
hum, I'm not what you mean.. what kernel code are you referring to?
thanks,
jirka
next prev parent reply other threads:[~2021-06-07 18:28 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-05 11:10 [RFCv3 00/19] x86/ftrace/bpf: Add batch support for direct/tracing attach Jiri Olsa
2021-06-05 11:10 ` [PATCH 01/19] x86/ftrace: Remove extra orig rax move Jiri Olsa
2021-06-05 11:10 ` [PATCH 02/19] x86/ftrace: Remove fault protection code in prepare_ftrace_return Jiri Olsa
2021-06-05 11:10 ` [PATCH 03/19] x86/ftrace: Make function graph use ftrace directly Jiri Olsa
2021-06-08 18:35 ` Andrii Nakryiko
2021-06-08 18:51 ` Jiri Olsa
2021-06-08 19:11 ` Steven Rostedt
2021-06-05 11:10 ` [PATCH 04/19] tracing: Add trampoline/graph selftest Jiri Olsa
2021-06-05 11:10 ` [PATCH 05/19] ftrace: Add ftrace_add_rec_direct function Jiri Olsa
2021-06-05 11:10 ` [PATCH 06/19] ftrace: Add multi direct register/unregister interface Jiri Olsa
2021-06-05 11:10 ` [PATCH 07/19] ftrace: Add multi direct modify interface Jiri Olsa
2021-06-05 11:10 ` [PATCH 08/19] ftrace/samples: Add multi direct interface test module Jiri Olsa
2021-06-05 11:10 ` [PATCH 09/19] bpf, x64: Allow to use caller address from stack Jiri Olsa
2021-06-07 3:07 ` Yonghong Song
2021-06-07 18:13 ` Jiri Olsa
2021-06-05 11:10 ` [PATCH 10/19] bpf: Allow to store caller's ip as argument Jiri Olsa
2021-06-07 3:21 ` Yonghong Song
2021-06-07 18:15 ` Jiri Olsa
2021-06-08 18:49 ` Andrii Nakryiko
2021-06-08 20:58 ` Jiri Olsa
2021-06-08 21:02 ` Andrii Nakryiko
2021-06-08 21:11 ` Jiri Olsa
2021-06-05 11:10 ` [PATCH 11/19] bpf: Add support to load multi func tracing program Jiri Olsa
2021-06-07 3:56 ` Yonghong Song
2021-06-07 18:18 ` Jiri Olsa
2021-06-07 19:35 ` Yonghong Song
2021-06-05 11:10 ` [PATCH 12/19] bpf: Add bpf_trampoline_alloc function Jiri Olsa
2021-06-05 11:10 ` [PATCH 13/19] bpf: Add support to link multi func tracing program Jiri Olsa
2021-06-07 5:36 ` Yonghong Song
2021-06-07 18:25 ` Jiri Olsa
2021-06-07 19:39 ` Yonghong Song
2021-06-08 15:42 ` Alexei Starovoitov
2021-06-08 18:17 ` Jiri Olsa
2021-06-08 18:49 ` Alexei Starovoitov
2021-06-08 21:07 ` Jiri Olsa
2021-06-08 23:05 ` Alexei Starovoitov
2021-06-09 5:08 ` Andrii Nakryiko
2021-06-09 13:42 ` Jiri Olsa
2021-06-09 13:33 ` Jiri Olsa
2021-06-09 5:18 ` Andrii Nakryiko
2021-06-09 13:53 ` Jiri Olsa
2021-06-05 11:10 ` [PATCH 14/19] libbpf: Add btf__find_by_pattern_kind function Jiri Olsa
2021-06-09 5:29 ` Andrii Nakryiko
2021-06-09 13:59 ` Jiri Olsa
2021-06-09 14:19 ` Jiri Olsa
2021-06-05 11:10 ` [PATCH 15/19] libbpf: Add support to link multi func tracing program Jiri Olsa
2021-06-07 5:49 ` Yonghong Song
2021-06-07 18:28 ` Jiri Olsa [this message]
2021-06-07 19:42 ` Yonghong Song
2021-06-07 20:11 ` Jiri Olsa
2021-06-09 5:34 ` Andrii Nakryiko
2021-06-09 14:17 ` Jiri Olsa
2021-06-10 17:05 ` Andrii Nakryiko
2021-06-10 20:35 ` Jiri Olsa
2021-06-05 11:10 ` [PATCH 16/19] selftests/bpf: Add fentry multi func test Jiri Olsa
2021-06-07 6:06 ` Yonghong Song
2021-06-07 18:42 ` Jiri Olsa
2021-06-09 5:40 ` Andrii Nakryiko
2021-06-09 14:29 ` Jiri Olsa
2021-06-10 17:00 ` Andrii Nakryiko
2021-06-10 20:28 ` Jiri Olsa
2021-06-05 11:10 ` [PATCH 17/19] selftests/bpf: Add fexit " Jiri Olsa
2021-06-05 11:10 ` [PATCH 18/19] selftests/bpf: Add fentry/fexit " Jiri Olsa
2021-06-09 5:41 ` Andrii Nakryiko
2021-06-09 14:29 ` Jiri Olsa
2021-06-05 11:10 ` [PATCH 19/19] selftests/bpf: Temporary fix for fentry_fexit_multi_test Jiri Olsa
2021-06-17 20:29 ` [RFCv3 00/19] x86/ftrace/bpf: Add batch support for direct/tracing attach Andrii Nakryiko
2021-06-19 8:33 ` Jiri Olsa
2021-06-19 16:19 ` Yonghong Song
2021-06-19 17:09 ` Jiri Olsa
2021-06-20 16:56 ` Yonghong Song
2021-06-20 17:47 ` Alexei Starovoitov
2021-06-21 6:46 ` Andrii Nakryiko
2021-06-21 6:50 ` Andrii Nakryiko
2021-07-06 20:26 ` Andrii Nakryiko
2021-07-07 15:19 ` Jiri Olsa
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YL5lYPJdx5mmd06F@krava \
--to=jolsa@redhat.com \
--cc=andriin@fb.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=dxu@dxuuu.xyz \
--cc=john.fastabend@gmail.com \
--cc=jolsa@kernel.org \
--cc=kafai@fb.com \
--cc=kpsingh@chromium.org \
--cc=netdev@vger.kernel.org \
--cc=rostedt@goodmis.org \
--cc=songliubraving@fb.com \
--cc=vmalik@redhat.com \
--cc=yhs@fb.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).