perf session: Parse sample earlier

At perf_session__process_event, so that we reduce the number of lines in eache
tool sample processing routine that now receives a sample_data pointer already
parsed.

This will also be useful in the next patch, where we'll allow sample the
identity fields in MMAP, FORK, EXIT, etc, when it will be possible to see (cpu,
timestamp) just after before every event.

Also validate callchains in perf_session__process_event, i.e. as early as
possible, and keep a counter of the number of events discarded due to invalid
callchains, warning the user about it if it happens.

There is an assumption that was kept that all events have the same sample_type,
that will be dealt with in the future, when this preexisting limitation will be
removed.

Tested-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <1291318772-30880-4-git-send-email-acme@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 78 insertions, 25 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 52672dad1fe9..08ec018966a8 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -70,6 +70,11 @@ void perf_session__update_sample_type(struct perf_session *self)
 	self->sample_type = perf_header__sample_type(&self->header);
 }
 
+void perf_session__set_sample_type(struct perf_session *session, u64 type)
+{
+	session->sample_type = type;
+}
+
 int perf_session__create_kernel_maps(struct perf_session *self)
 {
 	int ret = machine__create_kernel_maps(&self->host_machine);
@@ -240,7 +245,15 @@ struct map_symbol *perf_session__resolve_callchain(struct perf_session *self,
 	return syms;
 }
 
+static int process_event_synth_stub(event_t *event __used,
+				    struct perf_session *session __used)
+{
+	dump_printf(": unhandled!\n");
+	return 0;
+}
+
 static int process_event_stub(event_t *event __used,
+			      struct sample_data *sample __used,
 			      struct perf_session *session __used)
 {
 	dump_printf(": unhandled!\n");
@@ -280,13 +293,13 @@ static void perf_event_ops__fill_defaults(struct perf_event_ops *handler)
 	if (handler->unthrottle == NULL)
 		handler->unthrottle = process_event_stub;
 	if (handler->attr == NULL)
-		handler->attr = process_event_stub;
+		handler->attr = process_event_synth_stub;
 	if (handler->event_type == NULL)
-		handler->event_type = process_event_stub;
+		handler->event_type = process_event_synth_stub;
 	if (handler->tracing_data == NULL)
-		handler->tracing_data = process_event_stub;
+		handler->tracing_data = process_event_synth_stub;
 	if (handler->build_id == NULL)
-		handler->build_id = process_event_stub;
+		handler->build_id = process_event_synth_stub;
 	if (handler->finished_round == NULL) {
 		if (handler->ordered_samples)
 			handler->finished_round = process_finished_round;
@@ -419,6 +432,7 @@ static void flush_sample_queue(struct perf_session *s,
 	struct ordered_samples *os = &s->ordered_samples;
 	struct list_head *head = &os->samples;
 	struct sample_queue *tmp, *iter;
+	struct sample_data sample;
 	u64 limit = os->next_flush;
 	u64 last_ts = os->last_sample ? os->last_sample->timestamp : 0ULL;
 
@@ -429,7 +443,8 @@ static void flush_sample_queue(struct perf_session *s,
 		if (iter->timestamp > limit)
 			break;
 
-		ops->sample(iter->event, s);
+		event__parse_sample(iter->event, s->sample_type, &sample);
+		ops->sample(iter->event, &sample, s);
 
 		os->last_flush = iter->timestamp;
 		list_del(&iter->list);
@@ -578,20 +593,29 @@ static int queue_sample_event(event_t *event, struct sample_data *data,
 	return 0;
 }
 
-static int perf_session__process_sample(event_t *event, struct perf_session *s,
+static int perf_session__process_sample(event_t *event,
+					struct sample_data *sample,
+					struct perf_session *s,
 					struct perf_event_ops *ops)
 {
-	struct sample_data data;
-
 	if (!ops->ordered_samples)
-		return ops->sample(event, s);
+		return ops->sample(event, sample, s);
+
+	queue_sample_event(event, sample, s);
+	return 0;
+}
 
-	bzero(&data, sizeof(struct sample_data));
-	event__parse_sample(event, s->sample_type, &data);
+static void callchain__dump(struct sample_data *sample)
+{
+	unsigned int i;
 
-	queue_sample_event(event, &data, s);
+	if (!dump_trace)
+		return;
 
-	return 0;
+	printf("... chain: nr:%Lu\n", sample->callchain->nr);
+
+	for (i = 0; i < sample->callchain->nr; i++)
+		printf("..... %2d: %016Lx\n", i, sample->callchain->ips[i]);
 }
 
 static int perf_session__process_event(struct perf_session *self,
@@ -599,8 +623,16 @@ static int perf_session__process_event(struct perf_session *self,
 				       struct perf_event_ops *ops,
 				       u64 file_offset)
 {
+	struct sample_data sample;
+
 	trace_event(event);
 
+	if (self->header.needs_swap && event__swap_ops[event->header.type])
+		event__swap_ops[event->header.type](event);
+
+	if (event->header.type == PERF_RECORD_SAMPLE)
+		event__parse_sample(event, self->sample_type, &sample);
+
 	if (event->header.type < PERF_RECORD_HEADER_MAX) {
 		dump_printf("%#Lx [%#x]: PERF_RECORD_%s",
 			    file_offset, event->header.size,
@@ -608,28 +640,41 @@ static int perf_session__process_event(struct perf_session *self,
 		hists__inc_nr_events(&self->hists, event->header.type);
 	}
 
-	if (self->header.needs_swap && event__swap_ops[event->header.type])
-		event__swap_ops[event->header.type](event);
-
 	switch (event->header.type) {
 	case PERF_RECORD_SAMPLE:
-		return perf_session__process_sample(event, self, ops);
+		dump_printf("(IP, %d): %d/%d: %#Lx period: %Ld\n", event->header.misc,
+			    sample.pid, sample.tid, sample.ip, sample.period);
+
+		if (self->sample_type & PERF_SAMPLE_CALLCHAIN) {
+			if (!ip_callchain__valid(sample.callchain, event)) {
+				pr_debug("call-chain problem with event, "
+					 "skipping it.\n");
+				++self->hists.stats.nr_invalid_chains;
+				self->hists.stats.total_invalid_chains += sample.period;
+				return 0;
+			}
+
+			callchain__dump(&sample);
+		}
+
+		return perf_session__process_sample(event, &sample, self, ops);
+
 	case PERF_RECORD_MMAP:
-		return ops->mmap(event, self);
+		return ops->mmap(event, &sample, self);
 	case PERF_RECORD_COMM:
-		return ops->comm(event, self);
+		return ops->comm(event, &sample, self);
 	case PERF_RECORD_FORK:
-		return ops->fork(event, self);
+		return ops->fork(event, &sample, self);
 	case PERF_RECORD_EXIT:
-		return ops->exit(event, self);
+		return ops->exit(event, &sample, self);
 	case PERF_RECORD_LOST:
-		return ops->lost(event, self);
+		return ops->lost(event, &sample, self);
 	case PERF_RECORD_READ:
-		return ops->read(event, self);
+		return ops->read(event, &sample, self);
 	case PERF_RECORD_THROTTLE:
-		return ops->throttle(event, self);
+		return ops->throttle(event, &sample, self);
 	case PERF_RECORD_UNTHROTTLE:
-		return ops->unthrottle(event, self);
+		return ops->unthrottle(event, &sample, self);
 	case PERF_RECORD_HEADER_ATTR:
 		return ops->attr(event, self);
 	case PERF_RECORD_HEADER_EVENT_TYPE:
@@ -894,6 +939,14 @@ out_err:
 			    session->hists.stats.nr_unknown_events);
 	}
 
+ 	if (session->hists.stats.nr_invalid_chains != 0) {
+ 		ui__warning("Found invalid callchains!\n\n"
+ 			    "%u out of %u events were discarded for this reason.\n\n"
+ 			    "Consider reporting to linux-kernel@vger.kernel.org.\n\n",
+ 			    session->hists.stats.nr_invalid_chains,
+ 			    session->hists.stats.nr_events[PERF_RECORD_SAMPLE]);
+ 	}
+
 	perf_session_free_sample_buffers(session);
 	return err;
 }