[RFC PATCH 0/5] Split Coresight decode by aux records

James Clark james.clark at arm.com
Tue Feb 9 04:58:52 EST 2021

The following patches fix opening perf.data files that have timestamps
(ordered data), aren't recorded with --per-thread, and that have
discontinuous data in a single aux trace buffer.

I have some open questions:
 * Can cs_etm__update_queues() be removed from cs_etm__flush_events()?
 * Why does the second commit start making some files process correctly?
 * Is it ok to wait for the flush to start processing? Previously
   processing happened when the first aux record was delivered to
 * Do the aux records need to be saved into a new buffer or can they
   be pulled from elsewhere?

I also have some further changes to make to make per-thread mode work
where the cpu field of the sample is set to -1. And when there are
no timestamps cs_etm__process_timeless_queues() is used, which is a
completely different code path.


James Clark (5):
  perf cs-etm: Split up etm queue setup function
  perf cs-etm: Only search timestamp in current sample's queue.
  perf cs-etm: Save aux records in each etm queue
  perf cs-etm: don't process queues until cs_etm__flush_events
  perf cs-etm: split decode by aux records.

 tools/perf/util/cs-etm.c | 200 +++++++++++++++++++++++----------------
 1 file changed, 121 insertions(+), 79 deletions(-)


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