[PATCH 2/7] perf cs-etm: Only search timestamp in current sample's queue.

James Clark james.clark at arm.com
Fri Feb 12 09:45:08 EST 2021


Change initial timestamp search to only operate on the queue
related to the current event. In a later change the bounds
of the aux record will also be used to reset the decoder and
the record is only relevant to a single queue.

This change makes some files that had coresight data
but didn't syntesise any events start working and generating
events. I'm not sure of the reason for that. I'd expect this
change to only affect the ordering of events.

Signed-off-by: James Clark <james.clark at arm.com>
---
 tools/perf/util/cs-etm.c | 30 ++++++++++++++----------------
 1 file changed, 14 insertions(+), 16 deletions(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 27894facae5e..8f8b448632fb 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -97,7 +97,7 @@ struct cs_etm_queue {
 /* RB tree for quick conversion between traceID and metadata pointers */
 static struct intlist *traceid_list;
 
-static int cs_etm__update_queues(struct cs_etm_auxtrace *etm);
+static int cs_etm__update_queues(struct cs_etm_auxtrace *etm, int cpu);
 static int cs_etm__process_queues(struct cs_etm_auxtrace *etm);
 static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
 					   pid_t tid);
@@ -524,7 +524,6 @@ static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
 static int cs_etm__flush_events(struct perf_session *session,
 				struct perf_tool *tool)
 {
-	int ret;
 	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
 						   struct cs_etm_auxtrace,
 						   auxtrace);
@@ -534,11 +533,6 @@ static int cs_etm__flush_events(struct perf_session *session,
 	if (!tool->ordered_events)
 		return -EINVAL;
 
-	ret = cs_etm__update_queues(etm);
-
-	if (ret < 0)
-		return ret;
-
 	if (etm->timeless_decoding)
 		return cs_etm__process_timeless_queues(etm, -1);
 
@@ -851,10 +845,7 @@ static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
 	etmq->queue_nr = queue_nr;
 	etmq->offset = 0;
 
-	if (etm->timeless_decoding)
-		return 0;
-	else
-		return cs_etm__search_first_timestamp(etmq);
+	return 0;
 }
 
 static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
@@ -874,14 +865,20 @@ static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
 	return 0;
 }
 
-static int cs_etm__update_queues(struct cs_etm_auxtrace *etm)
+static int cs_etm__update_queues(struct cs_etm_auxtrace *etm, int cpu)
 {
+	int ret;
 	if (etm->queues.new_data) {
 		etm->queues.new_data = false;
-		return cs_etm__setup_queues(etm);
+		ret = cs_etm__setup_queues(etm);
+		if (ret)
+			return ret;
 	}
 
-	return 0;
+	if (!etm->timeless_decoding)
+		return cs_etm__search_first_timestamp(etm->queues.queue_array[cpu].priv);
+	else
+		return 0;
 }
 
 static inline
@@ -2358,8 +2355,9 @@ static int cs_etm__process_event(struct perf_session *session,
 	else
 		timestamp = 0;
 
-	if (timestamp || etm->timeless_decoding) {
-		err = cs_etm__update_queues(etm);
+	if ((timestamp || etm->timeless_decoding)
+			&& event->header.type == PERF_RECORD_AUX) {
+		err = cs_etm__update_queues(etm, sample->cpu);
 		if (err)
 			return err;
 	}
-- 
2.28.0




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