When tracing stops, there is no collision with other samples, so using
PERF_AUX_FLAG_COLLISION does not accurately reflect the trace state and
may mislead userspace.
Use PERF_AUX_FLAG_PARTIAL instead to indicate that tracing stopped and
the record may contain gaps.
Signed-off-by: Leo Yan <leo.yan@arm.com>
---
drivers/hwtracing/coresight/coresight-trbe.c | 19 ++++++-------------
1 file changed, 6 insertions(+), 13 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
index b06885a08e082fd34f68d9588518807b5c47c86e..0caa4a6b437a3aa39fc6bcc72a23711b54f7c598 100644
--- a/drivers/hwtracing/coresight/coresight-trbe.c
+++ b/drivers/hwtracing/coresight/coresight-trbe.c
@@ -669,21 +669,14 @@ static enum trbe_fault_action trbe_get_fault_act(struct perf_output_handle *hand
}
/*
- * Mark the buffer to indicate that there was a WRAP event by
- * setting the COLLISION flag. This indicates to the user that
- * the TRBE trace collection was stopped without stopping the
- * ETE and thus there might be some amount of trace that was
- * lost between the time the WRAP was detected and the IRQ
- * was consumed by the CPU.
- *
- * Setting the TRUNCATED flag would move the event to STOPPED
- * state unnecessarily, even when there is space left in the
- * ring buffer. Using the COLLISION flag doesn't have this side
- * effect. We only set TRUNCATED flag when there is no space
- * left in the ring buffer.
+ * Mark the buffer to indicate that the trace is stopped by setting
+ * the PARTIAL flag. This indicates to the user that the TRBE trace
+ * collection was stopped without stopping the ETE and thus there
+ * might be some amount of trace that was lost between the time the
+ * TRBE event was detected and the IRQ was consumed by the CPU.
*/
if (!is_trbe_running(trbsr))
- perf_aux_output_flag(handle, PERF_AUX_FLAG_COLLISION);
+ perf_aux_output_flag(handle, PERF_AUX_FLAG_PARTIAL);
if (is_trbe_wrap(trbsr))
return TRBE_FAULT_ACT_WRAP;
--
2.34.1