Re: [PATCH 0/2] Move bpf_num_possible_cpus() to libbpf_util

[Hechao Li <hechaol@xxxxxx>]

I put the implementation in libbpf_util.c mainly because it depends on pr_warning defined in libbpf_internal.h. If including libbpf_internal.h in libbpf_util.h, then the internal stuff will be exposed to whoever include libbpf_util.h. But let me know if there is a better way to print the error messages other than depending on libbpf_internal. 

Thanks,
Hechao

On 6/4/19, 4:40 PM, "Song Liu" <songliubraving@xxxxxx> wrote:

    
    > On Jun 4, 2019, at 3:38 PM, Hechao Li <hechaol@xxxxxx> wrote:
    > 
    > Getting number of possible CPUs is commonly used for per-CPU BPF maps 
    > and perf_event_maps. Putting it into a common place can avoid duplicate 
    > implementations.
    > 
    > Hechao Li (2):
    >  Add bpf_num_possible_cpus to libbpf_util
    >  Use bpf_num_possible_cpus in bpftool and selftests
    > 
    > tools/bpf/bpftool/common.c                    | 53 ++--------------
    > tools/lib/bpf/Build                           |  2 +-
    > tools/lib/bpf/libbpf_util.c                   | 61 +++++++++++++++++++
    > tools/lib/bpf/libbpf_util.h                   |  7 +++
    > tools/testing/selftests/bpf/bpf_util.h        | 42 +++----------
    > .../selftests/bpf/prog_tests/l4lb_all.c       |  2 +-
    > .../selftests/bpf/prog_tests/xdp_noinline.c   |  2 +-
    > tools/testing/selftests/bpf/test_btf.c        |  2 +-
    > tools/testing/selftests/bpf/test_lru_map.c    |  2 +-
    > tools/testing/selftests/bpf/test_maps.c       |  6 +-
    > 10 files changed, 88 insertions(+), 91 deletions(-)
    > create mode 100644 tools/lib/bpf/libbpf_util.c
    > 
    > -- 
    > 2.17.1
    > 
    
    The change is mostly straightforward. However, I am not sure whether
    they should be added to libbpf_util.h. Maybe libbpf.h is a better 
    place?
    
    Daniel and Alexei, what's your recommendation here? 
    
    Thanks,
    Song