Re: [PATCH 3/6] perf cs-etm: Synthesize missing HW_ID mappings for raw trace

On Fri, Aug 21, 2026 at 10:50:31AM +0100, James Clark wrote:

[...]

+static int cs_etm__synth_unformatted_trace_ids(struct cs_etm_auxtrace *etm) +{

• struct auxtrace_queues *queues = &etm->queues;
• for (unsigned int i = 0; i < queues->nr_queues; i++) {

• struct auxtrace_queue *queue = &queues->queue_array[i];
  

• struct cs_etm_queue *etmq = queue->priv;
  

• u64 *cpu_data;
  

• u8 trace_id;
  

• int ret;
  

• if (list_empty(&queue->head) || !etmq || etmq->format != UNFORMATTED)
  

• 	continue;
  

• if (!intlist__empty(etmq->traceid_list))
  

• 	continue;
  

• cpu_data = get_cpu_data(etm, queue->cpu);
  

• if (!cpu_data)
  

• 	return -EINVAL;
  

• ret = cs_etm__metadata_get_trace_id(&trace_id, cpu_data);
  

• if (ret)
  

• 	return ret;
  

Since this is an unformatted queue, can we simply ignore the trace ID? Instead of fetching it from the metadata, we could insert 0 to create the trace ID list.

This would also align with future refactoring to remove trace ID handling for unformatted queues.