Re: [PATCH 10/12] perf script: Add --show-bpf-events to show eBPF related events

[Song Liu]

> On May 7, 2019, at 1:18 AM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
> 
> On Mon, May 06, 2019 at 09:42:44PM +0000, Song Liu wrote:
> 
> SNIP
> 
>>> +static int
>>> +process_bpf_events(struct perf_tool *tool __maybe_unused,
>>> +		   union perf_event *event,
>>> +		   struct perf_sample *sample,
>>> +		   struct machine *machine)
>>> +{
>>> +	struct thread *thread;
>>> +	struct perf_script *script = container_of(tool, struct perf_script, tool);
>>> +	struct perf_session *session = script->session;
>>> +	struct perf_evsel *evsel = perf_evlist__id2evsel(session->evlist, sample->id);
>>> +
>>> +	if (machine__process_ksymbol(machine, event, sample) < 0)
>>> +		return -1;
>>> +
>>> +	if (!evsel->attr.sample_id_all) {
>>> +		perf_event__fprintf(event, stdout);
>>> +		return 0;
>>> +	}
>>> +
>>> +	thread = machine__findnew_thread(machine, sample->pid, sample->tid);
>>> +	if (thread == NULL) {
>>> +		pr_debug("problem processing MMAP event, skipping it.\n");
>>> +		return -1;
>>> +	}
>>> +
>>> +	if (!filter_cpu(sample)) {
>>> +		perf_sample__fprintf_start(sample, thread, evsel,
>>> +					   event->header.type, stdout);
>>> +		perf_event__fprintf(event, stdout);
>>> +	}
>>> +
>>> +	thread__put(thread);
>>> +	return 0;
>>> +}
>>> +
>>> static void sig_handler(int sig __maybe_unused)
>>> {
>>> 	session_done = 1;
>>> @@ -2420,6 +2456,10 @@ static int __cmd_script(struct perf_script *script)
>>> 		script->tool.ordered_events = false;
>>> 		script->tool.finished_round = process_finished_round_event;
>>> 	}
>>> +	if (script->show_bpf_events) {
>>> +		script->tool.ksymbol   = process_bpf_events;
>>> +		script->tool.bpf_event = process_bpf_events;
>> 
>> Why do we need both set to process_bpf_events?
> 
> --show-*-events option is there to display all the related events for given '*'
> 
> we want to display both ksymbol and bpf_event in here,
> process_bpf_events takes care of it for both of them

I see. Thanks for the explanation!

Song