netdev - Re: [PATCH v4 bpf-next 0/4] libbpf: add perf buffer abstraction and API

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CAEf4BzYRAAqJAS9UuOAcnmeZegRzV3ygBWfqoy-LW-8qOgAqqg@mail.gmail.com>
Date:   Wed, 3 Jul 2019 09:27:17 -0700
From:   Andrii Nakryiko <andrii.nakryiko@...il.com>
To:     Daniel Borkmann <daniel@...earbox.net>
Cc:     Andrii Nakryiko <andriin@...com>, Alexei Starovoitov <ast@...com>,
        Kernel Team <kernel-team@...com>, bpf <bpf@...r.kernel.org>,
        Networking <netdev@...r.kernel.org>,
        Jakub Kicinski <jakub.kicinski@...ronome.com>
Subject: Re: [PATCH v4 bpf-next 0/4] libbpf: add perf buffer abstraction and API

On Wed, Jul 3, 2019 at 2:36 AM Daniel Borkmann <daniel@...earbox.net> wrote:
>
> On 06/30/2019 08:51 AM, Andrii Nakryiko wrote:
> > This patchset adds a high-level API for setting up and polling perf buffers
> > associated with BPF_MAP_TYPE_PERF_EVENT_ARRAY map. Details of APIs are
> > described in corresponding commit.
> >
> > Patch #1 adds a set of APIs to set up and work with perf buffer.
> > Patch #2 enhances libbpf to support auto-setting PERF_EVENT_ARRAY map size.
> > Patch #3 adds test.
> > Patch #4 converts bpftool map event_pipe to new API.
> >
> > v3->v4:
> > - fixed bpftool event_pipe cmd error handling (Jakub);
> >
> > v2->v3:
> > - added perf_buffer__new_raw for more low-level control;
> > - converted bpftool map event_pipe to new API (Daniel);
> > - fixed bug with error handling in create_maps (Song);
> >
> > v1->v2:
> > - add auto-sizing of PERF_EVENT_ARRAY maps;
> >
> > Andrii Nakryiko (4):
> >   libbpf: add perf buffer API
> >   libbpf: auto-set PERF_EVENT_ARRAY size to number of CPUs
> >   selftests/bpf: test perf buffer API
> >   tools/bpftool: switch map event_pipe to libbpf's perf_buffer
> >
> >  tools/bpf/bpftool/map_perf_ring.c             | 201 +++------
> >  tools/lib/bpf/libbpf.c                        | 397 +++++++++++++++++-
> >  tools/lib/bpf/libbpf.h                        |  49 +++
> >  tools/lib/bpf/libbpf.map                      |   4 +
> >  .../selftests/bpf/prog_tests/perf_buffer.c    |  94 +++++
> >  .../selftests/bpf/progs/test_perf_buffer.c    |  29 ++
> >  6 files changed, 630 insertions(+), 144 deletions(-)
> >  create mode 100644 tools/testing/selftests/bpf/prog_tests/perf_buffer.c
> >  create mode 100644 tools/testing/selftests/bpf/progs/test_perf_buffer.c
>
> Hm, set looks good, but this does not apply cleanly. Please rebase against
> bpf-next and resubmit. Please also update tools/lib/bpf/README.rst with regards
> to the perf_buffer__ prefix. While at it, you could also address Jakub's comment.

Yeah, I forgot to mention that in cover letter: this patchset is using
APIs added in my other patch set (tracing APIs), so that one has to go
in first. I'll wait for it to land and will update and post v5,
updating README and initializing ops (Jakub's feedback). Thanks!

>
> Thanks,
> Daniel