perf intel-pt: Add support for decoding AUX area samples

Add support for dumping, queuing and decoding AUX area samples. Decoding
samples is the same as regular decoding, except in the case where there
are no timestamps, in which case buffers are decoded immediately before
the sample event.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-15-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/intel-pt.c

@@ -233,6 +233,16 @@ static void intel_pt_log_event(union perf_event *event)
 	perf_event__fprintf(event, f);
 }
 
+static void intel_pt_dump_sample(struct perf_session *session,
+				 struct perf_sample *sample)
+{
+	struct intel_pt *pt = container_of(session->auxtrace, struct intel_pt,
+					   auxtrace);
+
+	printf("\n");
+	intel_pt_dump(pt, sample->aux_sample.data, sample->aux_sample.size);
+}
+
 static int intel_pt_do_fix_overlap(struct intel_pt *pt, struct auxtrace_buffer *a,
 				   struct auxtrace_buffer *b)
 {
@@ -836,6 +846,18 @@ static bool intel_pt_have_tsc(struct intel_pt *pt)
 	return have_tsc;
 }
 
+static bool intel_pt_sampling_mode(struct intel_pt *pt)
+{
+	struct evsel *evsel;
+
+	evlist__for_each_entry(pt->session->evlist, evsel) {
+		if ((evsel->core.attr.sample_type & PERF_SAMPLE_AUX) &&
+		    evsel->core.attr.aux_sample_size)
+			return true;
+	}
+	return false;
+}
+
 static u64 intel_pt_ns_to_ticks(const struct intel_pt *pt, u64 ns)
 {
 	u64 quot, rem;
@@ -2320,6 +2342,56 @@ static int intel_pt_process_timeless_queues(struct intel_pt *pt, pid_t tid,
 	return 0;
 }
 
+static void intel_pt_sample_set_pid_tid_cpu(struct intel_pt_queue *ptq,
+					    struct auxtrace_queue *queue,
+					    struct perf_sample *sample)
+{
+	struct machine *m = ptq->pt->machine;
+
+	ptq->pid = sample->pid;
+	ptq->tid = sample->tid;
+	ptq->cpu = queue->cpu;
+
+	intel_pt_log("queue %u cpu %d pid %d tid %d\n",
+		     ptq->queue_nr, ptq->cpu, ptq->pid, ptq->tid);
+
+	thread__zput(ptq->thread);
+
+	if (ptq->tid == -1)
+		return;
+
+	if (ptq->pid == -1) {
+		ptq->thread = machine__find_thread(m, -1, ptq->tid);
+		if (ptq->thread)
+			ptq->pid = ptq->thread->pid_;
+		return;
+	}
+
+	ptq->thread = machine__findnew_thread(m, ptq->pid, ptq->tid);
+}
+
+static int intel_pt_process_timeless_sample(struct intel_pt *pt,
+					    struct perf_sample *sample)
+{
+	struct auxtrace_queue *queue;
+	struct intel_pt_queue *ptq;
+	u64 ts = 0;
+
+	queue = auxtrace_queues__sample_queue(&pt->queues, sample, pt->session);
+	if (!queue)
+		return -EINVAL;
+
+	ptq = queue->priv;
+	if (!ptq)
+		return 0;
+
+	ptq->stop = false;
+	ptq->time = sample->time;
+	intel_pt_sample_set_pid_tid_cpu(ptq, queue, sample);
+	intel_pt_run_decoder(ptq, &ts);
+	return 0;
+}
+
 static int intel_pt_lost(struct intel_pt *pt, struct perf_sample *sample)
 {
 	return intel_pt_synth_error(pt, INTEL_PT_ERR_LOST, sample->cpu,
@@ -2550,7 +2622,11 @@ static int intel_pt_process_event(struct perf_session *session,
 	}
 
 	if (pt->timeless_decoding) {
-		if (event->header.type == PERF_RECORD_EXIT) {
+		if (pt->sampling_mode) {
+			if (sample->aux_sample.size)
+				err = intel_pt_process_timeless_sample(pt,
+								       sample);
+		} else if (event->header.type == PERF_RECORD_EXIT) {
 			err = intel_pt_process_timeless_queues(pt,
 							       event->fork.tid,
 							       sample->time);
@@ -2676,6 +2752,28 @@ static int intel_pt_process_auxtrace_event(struct perf_session *session,
 	return 0;
 }
 
+static int intel_pt_queue_data(struct perf_session *session,
+			       struct perf_sample *sample,
+			       union perf_event *event, u64 data_offset)
+{
+	struct intel_pt *pt = container_of(session->auxtrace, struct intel_pt,
+					   auxtrace);
+	u64 timestamp;
+
+	if (event) {
+		return auxtrace_queues__add_event(&pt->queues, session, event,
+						  data_offset, NULL);
+	}
+
+	if (sample->time && sample->time != (u64)-1)
+		timestamp = perf_time_to_tsc(sample->time, &pt->tc);
+	else
+		timestamp = 0;
+
+	return auxtrace_queues__add_sample(&pt->queues, session, sample,
+					   data_offset, timestamp);
+}
+
 struct intel_pt_synth {
 	struct perf_tool dummy_tool;
 	struct perf_session *session;
@@ -3178,7 +3276,7 @@ int intel_pt_process_auxtrace_info(union perf_event *event,
 	if (pt->timeless_decoding && !pt->tc.time_mult)
 		pt->tc.time_mult = 1;
 	pt->have_tsc = intel_pt_have_tsc(pt);
-	pt->sampling_mode = false;
+	pt->sampling_mode = intel_pt_sampling_mode(pt);
 	pt->est_tsc = !pt->timeless_decoding;
 
 	pt->unknown_thread = thread__new(999999999, 999999999);
@@ -3205,6 +3303,8 @@ int intel_pt_process_auxtrace_info(union perf_event *event,
 
 	pt->auxtrace.process_event = intel_pt_process_event;
 	pt->auxtrace.process_auxtrace_event = intel_pt_process_auxtrace_event;
+	pt->auxtrace.queue_data = intel_pt_queue_data;
+	pt->auxtrace.dump_auxtrace_sample = intel_pt_dump_sample;
 	pt->auxtrace.flush_events = intel_pt_flush;
 	pt->auxtrace.free_events = intel_pt_free_events;
 	pt->auxtrace.free = intel_pt_free;
@@ -3282,7 +3382,10 @@ int intel_pt_process_auxtrace_info(union perf_event *event,
 
 	intel_pt_setup_pebs_events(pt);
 
-	err = auxtrace_queues__process_index(&pt->queues, session);
+	if (pt->sampling_mode || list_empty(&session->auxtrace_index))
+		err = auxtrace_queue_data(session, true, true);
+	else
+		err = auxtrace_queues__process_index(&pt->queues, session);
 	if (err)
 		goto err_delete_thread;