[PATCH] perf: cs-etm: Fix the assert() to handle captured and unprocessed cpu trace

Ilkka Koskinen ilkka at os.amperecomputing.com
Tue Sep 24 16:39:30 PDT 2024


If one builds perf with DEBUG=1, captures data on multiple CPUs and
finally runs 'perf report -C <cpu>' for only one of the cpus, assert()
aborts the program. This happens because there are empty queues with
format set. This patch changes the condition to abort only if a queue
is not empty and if the format is unset.

  $ make -C tools/perf DEBUG=1 CORESIGHT=1 CSLIBS=/usr/lib CSINCLUDES=/usr/include install
  $ perf record -o kcore --kcore -e cs_etm/timestamp/k -s -C 0-1 dd if=/dev/zero of=/dev/null bs=1M count=1
  $ perf report --input kcore/data --vmlinux=/home/ikoskine/projects/linux/vmlinux -C 1
  Aborted (core dumped)

Fixes: 57880a7966be ("perf: cs-etm: Allocate queues for all CPUs")
Signed-off-by: Ilkka Koskinen <ilkka at os.amperecomputing.com>
---
 tools/perf/util/cs-etm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 90f32f327b9b..40f047baef81 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -3323,7 +3323,7 @@ static int cs_etm__create_decoders(struct cs_etm_auxtrace *etm)
 		 * Don't create decoders for empty queues, mainly because
 		 * etmq->format is unknown for empty queues.
 		 */
-		assert(empty == (etmq->format == UNSET));
+		assert(empty || etmq->format != UNSET);
 		if (empty)
 			continue;
 
-- 
2.42.0




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