Re: [PATCH v6 bpf-next 0/5] libbpf: add perf buffer abstraction and API

[Yonghong Song <yhs@fb.com>]

On 7/5/19 11:02 PM, 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.
> Patch #5 updates README to mention perf_buffer_ prefix.
> 
> v5->v6:
> - fix C99 for loop variable initialization usage (Yonghong);
> v4->v5:
> - initialize perf_buffer_raw_opts in bpftool map event_pipe (Jakub);
> - add perf_buffer_ to README;
> 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 (5):
>    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
>    libbpf: add perf_buffer_ prefix to README
> 
>   tools/bpf/bpftool/map_perf_ring.c             | 201 +++------
>   tools/lib/bpf/README.rst                      |   3 +-
>   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    |  25 ++
>   7 files changed, 628 insertions(+), 145 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

With a minor comment on patch 3/5 in a different thread,
LGTM. Ack for the whole series.
Acked-by: Yonghong Song <yhs@fb.com>