bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andrii Nakryiko <andrii.nakryiko@gmail.com>
To: David Ahern <dsahern@gmail.com>
Cc: Andrii Nakryiko <andriin@fb.com>, bpf <bpf@vger.kernel.org>,
	Networking <netdev@vger.kernel.org>,
	Alexei Starovoitov <ast@fb.com>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Kernel Team <kernel-team@fb.com>
Subject: Re: [PATCH v3 bpf-next 5/7] libbpf: move bpf_{helpers,endian,tracing}.h into libbpf
Date: Fri, 4 Oct 2019 08:27:58 -0700	[thread overview]
Message-ID: <CAEf4BzYRJ4i05prEJF_aCQK5jnmpSUqrwTXYsj4FDahCWcNQdQ@mail.gmail.com> (raw)
In-Reply-To: <da73636f-7d81-1fe0-65af-aa32f7654c57@gmail.com>

On Fri, Oct 4, 2019 at 7:47 AM David Ahern <dsahern@gmail.com> wrote:
>
> On 10/3/19 3:28 PM, Andrii Nakryiko wrote:
> > Move bpf_helpers.h, bpf_tracing.h, and bpf_endian.h into libbpf. Ensure
> > they are installed along the other libbpf headers. Also, adjust
> > selftests and samples include path to include libbpf now.
>
> There are side effects to bringing bpf_helpers.h into libbpf if this
> gets propagated to the github sync.
>
> bpf_helpers.h references BPF_FUNC_* which are defined in the
> uapi/linux/bpf.h header. That is a kernel version dependent api file
> which means attempts to use newer libbpf with older kernel headers is
> going to throw errors when compiling bpf programs -- bpf_helpers.h will
> contain undefined BPF_FUNC references.

That's true, but I'm wondering if maintaining a copy of that enum in
bpf_helpers.h itself is a good answer here?

bpf_helpers.h will be most probably used with BPF CO-RE and
auto-generated vmlinux.h with all the enums and types. In that case,
you'll probably want to use vmlinux.h for one of the latest kernels
anyways.

Nevertheless, it is a problem and thanks for bringing it up! I'd say
for now we should still go ahead with this move and try to solve with
issue once bpf_helpers.h is in libbpf. If bpf_helpers.h doesn't work
for someone, it's no worse than it is today when users don't have
bpf_helpers.h at all.

  reply	other threads:[~2019-10-04 15:28 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-03 21:28 [PATCH v3 bpf-next 0/7] Move bpf_helpers and add BPF_CORE_READ macros Andrii Nakryiko
2019-10-03 21:28 ` [PATCH v3 bpf-next 1/7] selftests/bpf: undo GCC-specific bpf_helpers.h changes Andrii Nakryiko
2019-10-04  7:00   ` Toke Høiland-Jørgensen
2019-10-03 21:28 ` [PATCH v3 bpf-next 2/7] selftests/bpf: samples/bpf: split off legacy stuff from bpf_helpers.h Andrii Nakryiko
2019-10-04  7:00   ` Toke Høiland-Jørgensen
2019-10-03 21:28 ` [PATCH v3 bpf-next 3/7] selftests/bpf: adjust CO-RE reloc tests for new bpf_core_read() macro Andrii Nakryiko
2019-10-03 21:28 ` [PATCH v3 bpf-next 4/7] selftests/bpf: split off tracing-only helpers into bpf_tracing.h Andrii Nakryiko
2019-10-04  7:01   ` Toke Høiland-Jørgensen
2019-10-03 21:28 ` [PATCH v3 bpf-next 5/7] libbpf: move bpf_{helpers,endian,tracing}.h into libbpf Andrii Nakryiko
2019-10-04  7:01   ` Toke Høiland-Jørgensen
2019-10-04 14:47   ` David Ahern
2019-10-04 15:27     ` Andrii Nakryiko [this message]
2019-10-04 15:44       ` David Ahern
2019-10-04 16:00         ` Andrii Nakryiko
2019-10-04 18:30           ` Jakub Kicinski
2019-10-04 18:37             ` Yonghong Song
2019-10-04 21:04               ` Jakub Kicinski
2019-10-08 15:37               ` Jiri Benc
2019-10-08 18:02                 ` Andrii Nakryiko
2019-10-04 20:21             ` Andrii Nakryiko
2019-10-04 21:06               ` Daniel Borkmann
2019-10-04 21:58                 ` Daniel Borkmann
2019-10-04 22:47                   ` Andrii Nakryiko
2019-10-04 22:51                     ` Andrii Nakryiko
2019-10-04 23:25                       ` Andrii Nakryiko
2019-10-08 15:29             ` Jiri Benc
2019-10-03 21:28 ` [PATCH v3 bpf-next 6/7] libbpf: add BPF_CORE_READ/BPF_CORE_READ_INTO helpers Andrii Nakryiko
2019-10-03 21:28 ` [PATCH v3 bpf-next 7/7] selftests/bpf: add BPF_CORE_READ and BPF_CORE_READ_STR_INTO macro tests Andrii Nakryiko

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=CAEf4BzYRJ4i05prEJF_aCQK5jnmpSUqrwTXYsj4FDahCWcNQdQ@mail.gmail.com \
    --to=andrii.nakryiko@gmail.com \
    --cc=andriin@fb.com \
    --cc=ast@fb.com \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=dsahern@gmail.com \
    --cc=kernel-team@fb.com \
    --cc=netdev@vger.kernel.org \
    /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).