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

[Liang, Kan]

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.

Thanks,
Kan
> The previous discussion was at
> 
>   https://lore.kernel.org/all/CAM9d7cjj0X90=NsvdwaLMGCDVkMJBLAGF_q-+Eqj6b44OAnzoQ@xxxxxxxxxxxxxx/
> 
> Thanks,
> Namhyung
> 
>>
>> Kan Liang (6):
>>   perf: Add sample_flags to indicate the PMU-filled sample data
>>   perf/x86/intel/pebs: Fix PEBS timestamps overwritten
>>   perf: Use sample_flags for branch stack
>>   perf: Use sample_flags for weight
>>   perf: Use sample_flags for data_src
>>   perf: Use sample_flags for txn
>>
>>  arch/powerpc/perf/core-book3s.c | 10 ++++++---
>>  arch/x86/events/core.c          |  4 +++-
>>  arch/x86/events/intel/core.c    |  4 +++-
>>  arch/x86/events/intel/ds.c      | 39 ++++++++++++++++++++++++---------
>>  include/linux/perf_event.h      | 15 ++++++-------
>>  kernel/events/core.c            | 33 +++++++++++++++++++---------
>>  6 files changed, 72 insertions(+), 33 deletions(-)
>>
>> -- 
>> 2.35.1
>>
>>