[0/4] rtla: Collect and print number of missed events

Message

Tomas Glozar Jan. 23, 2025, 2:23 p.m. UTC

Due to tracefs buffer overflow, it can happen that rtla misses events,
making the tracing results inaccurate.

Count both the number of missed events and the total number of processed
events, and display missed events as well as their percentage. The numbers
are displayed for both osnoise and timerlat, even though for the earlier,
missed events are generally not expected.

For hist, the number is displayed at the end of the run; for top, it is
displayed on each printing of the top table.

Note: In the future, rtla might transition to using ftrace histogram
triggers to collect data. In that case, this code will be removed;
nevertheless, it is necessary until that happens.

Tomas Glozar (4):
  rtla: Count missed trace events
  rtla: Count all processed events
  rtla: Add function to report missed events
  rtla: Report missed event count

 tools/tracing/rtla/src/osnoise.c       | 20 ++++++++++++++
 tools/tracing/rtla/src/osnoise.h       |  1 +
 tools/tracing/rtla/src/osnoise_hist.c  |  1 +
 tools/tracing/rtla/src/osnoise_top.c   |  1 +
 tools/tracing/rtla/src/timerlat_hist.c |  1 +
 tools/tracing/rtla/src/timerlat_top.c  |  1 +
 tools/tracing/rtla/src/trace.c         | 38 ++++++++++++++++++++++++++
 tools/tracing/rtla/src/trace.h         |  2 ++
 8 files changed, 65 insertions(+)