Thank you for your time and effort for the review :)
Best,
Daniel
On Sun, Mar 22, 2020 at 4:43 AM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> On Sat, Mar 21, 2020 at 3:04 AM Daniel T. Lee <danieltimlee@xxxxxxxxx> wrote:
> >
> > 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. Also, bpf_link__destroy manages the close() of
> > perf_event fd.
> >
> > This commit refactors samples that attach the bpf program to perf_event
> > by using libbbpf instead of ioctl. Also the bpf_load in the samples were
> > removed and migrated to use libbbpf API.
> >
> > Signed-off-by: Daniel T. Lee <danieltimlee@xxxxxxxxx>
> >
> > ---
>
> LGTM.
>
> Acked-by: Andrii Nakryiko <andriin@xxxxxx>
>
> > 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
> > - find program with name explicitly instead of bpf_program__next
> > - unconditional bpf_link__destroy() on cleanup
> >
> > Changes in v4:
> > - bpf_link *, bpf_object * set NULL on init & err for easier destroy
> > - close bpf object with bpf_object__close()
> >
> > Changes in v5:
> > - on error, return error code with exit
> >
> > samples/bpf/Makefile | 4 +-
> > samples/bpf/sampleip_user.c | 98 +++++++++++++++--------
> > samples/bpf/trace_event_user.c | 139 ++++++++++++++++++++++-----------
> > 3 files changed, 159 insertions(+), 82 deletions(-)
> >
>
> [...]
