Re: [PATCH 1/6] perf: cs-etm: Don't add global v0 HW_IDs to unformatted queues

From: Leo Yan

Date: Fri Sep 04 2026 - 14:11:13 EST


On Fri, Aug 21, 2026 at 10:50:29AM +0100, James Clark wrote:
> In the case of mixed formatted and unformatted trace with v0 HW_IDs, or
> no HW_IDs at all resulting in the cs_etm__map_trace_ids_metadata()
> fallback, formatted queues will write their HW_IDs to unformatted
> queues.

I understand a session can support multiple sinks, but I don't expect
to mix up formatted and unformatted trace (see sinks_compatible()).

For the mentioned fallback, I am also struggling to establish a case.
Even AUX_OUTPUT_HW_ID records are absent randomly, I don't think this
impacts the queue's format initalization, no?