Re: [PATCH 0/6] Add sample_flags to improve the perf_sample_data struct

From: Namhyung Kim
Date: Fri Sep 02 2022 - 01:24:34 EST


On Thu, Sep 1, 2022 at 5:47 AM Liang, Kan <kan.liang@xxxxxxxxxxxxxxx> wrote:
>
>
>
> On 2022-08-31 6:42 p.m., Namhyung Kim wrote:
> > (Adding Ravi to CC)
> >
> > On Wed, Aug 31, 2022 at 07:55:08AM -0700, kan.liang@xxxxxxxxxxxxxxx wrote:
> >> From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
> >>
> >> The patch series is to fix PEBS timestamps overwritten and improve the
> >> perf_sample_data struct. The detailed discussion can be found at
> >> https://lore.kernel.org/lkml/YwXvGe4%2FQdgGYOKJ@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
> >>
> >> The patch series has two changes compared with the suggestions in the
> >> above discussion.
> >> - Only clear the sample flags for the perf_prepare_sample().
> >> The __perf_event_header__init_id is shared between perf_prepare_sample()
> >> (used by PERF_RECORD_SAMPLE) and perf_event_header__init_id() (used by
> >> other PERF_RECORD_* event type). The sample data is only available
> >> for the PERF_RECORD_SAMPLE.
> >> - The CALLCHAIN_EARLY hack is still required for the BPF, especially
> >> perf_event_set_bpf_handler(). The sample data is not available when
> >> the function is invoked.
> >
> > In general, looks good! I'd like to work on the BPF side so that it can
> > get the sample data for filtering.
>
> Thanks Namhyung. I will send out the V2 shortly. I think the BPF work
> can be on top of it.

Yep, I'll work on it once this patchset is merged.

Thanks,
Namhyung