netdev - [PATCH bpf-next v3 0/2] Refactor perf_event sample user program with libbpf bpf

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-next>] [day] [month] [year] [list]

Message-Id: <20200313115220.29073-1-danieltimlee@gmail.com>
Date:   Fri, 13 Mar 2020 20:52:18 +0900
From:   "Daniel T. Lee" <danieltimlee@...il.com>
To:     Daniel Borkmann <daniel@...earbox.net>,
        Alexei Starovoitov <ast@...nel.org>
Cc:     John Fastabend <john.fastabend@...il.com>,
        Andrii Nakryiko <andrii.nakryiko@...il.com>,
        netdev@...r.kernel.org, bpf@...r.kernel.org
Subject: [PATCH bpf-next v3 0/2] Refactor perf_event sample user program with libbpf bpf_link

Currently, some samples are using ioctl for enabling perf_event and
attaching BPF programs to this event. However, the bpf_program__attach
of libbpf(using bpf_link) is much more intuitive than the previous
method using ioctl.

bpf_program__attach_perf_event manages the enable of perf_event and
attach of BPF programs to it, so there's no neeed to do this
directly with ioctl.

In addition, bpf_link provides consistency in the use of API because it
allows disable (detach, destroy) for multiple events to be treated as
one bpf_link__destroy.

To refactor samples with using this libbpf API, the bpf_load in the
samples were removed and migrated to libbbpf. Because read_trace_pipe
is used in bpf_load, multiple samples cannot be migrated to libbpf,
this function was moved to trace_helpers.

Changes in v2:
 - check memory allocation is successful
 - clean up allocated memory on error

Changes in v3:
 - Improve pointer error check (IS_ERR())
 - change to calloc for easier destroy of bpf_link
 - remove perf_event fd list since bpf_link handles fd
 - use newer bpf_object__{open/load} API instead of bpf_prog_load
 - perf_event for _SC_NPROCESSORS_ONLN instead of _SC_NPROCESSORS_CONF
 - sample specific chagnes...

Daniel T. Lee (2):
  samples: bpf: move read_trace_pipe to trace_helpers
  samples: bpf: refactor perf_event user program with libbpf bpf_link

 samples/bpf/Makefile                        |   8 +-
 samples/bpf/bpf_load.c                      |  20 ----
 samples/bpf/bpf_load.h                      |   1 -
 samples/bpf/sampleip_user.c                 | 100 +++++++++++++-------
 samples/bpf/trace_event_user.c              |  89 ++++++++++++-----
 samples/bpf/tracex1_user.c                  |   1 +
 samples/bpf/tracex5_user.c                  |   1 +
 tools/testing/selftests/bpf/trace_helpers.c |  23 +++++
 tools/testing/selftests/bpf/trace_helpers.h |   1 +
 9 files changed, 159 insertions(+), 85 deletions(-)

-- 
2.25.1