Re: [External] Re: [RFC 00/12] perf record: Add event action support

[Yang Jihong]

Hello,

On 11/29/24 04:14, Arnaldo Carvalho de Melo wrote:
> On Thu, Nov 28, 2024 at 09:35:41PM +0800, Yang Jihong wrote:
> > In perf-record, when an event is triggered, default behavior is to
> > save sample data to perf.data. Sometimes, we may just want to do
> > some lightweight actions, such as printing a log.
>
> > Based on this requirement, add the --action option to the event to
> > specify the behavior when the event occurs.
>
> 'perf record' is centered on saving data to disk without processing
> events, while it has sideband events for some needs, like processing BPF
> related events (PERF_RECORD_BPF_EVENT to catch PERF_BPF_EVENT_PROG_LOAD
> and UNLOAD), doing things in a "live" way as your patchkit does seems
> more appropriate to do in 'perf trace' :-)

Ok, we can put it in "perf trace".

> I'll take a look at the rest of the patch series.

Thanks for reviewing this patchset. Currently, this patchset only 
implements a print() call and only supports attaching to tracepoints. 
The functionality is relatively simple.

Eventually, we can use bpf prog to allow users to customize the sampled 
data to and the processing of the data.

we can continue to expand the functionality (for example, attaching to 
kprobe events, printing the parameters and return values ​​of the target 
function)


Thanks,
Yang