Messages in this thread | ![/](/images/icornerl.gif) | | From | Adrian Hunter <> | Subject | [PATCH RFC V2 0/4] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing | Date | Fri, 8 Dec 2023 19:24:45 +0200 |
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Hi
Hardware traces, such as instruction traces, can produce a vast amount of trace data, so being able to reduce tracing to more specific circumstances can be useful.
The ability to pause or resume tracing when another event happens, can do that.
These patches add such a facilty and show how it would work for Intel Processor Trace.
Maintainers of other AUX area tracing implementations are requested to consider if this is something they might employ and then whether or not the ABI would work for them.
Changes to perf tools are not fleshed out yet.
Changes in RFC V2:
Use ->stop() / ->start() instead of ->pause_resume() Move aux_start_paused bit into aux_output_cfg Tighten up when Intel PT pause / resume is allowed Add an example of how it might work for CoreSight
Adrian Hunter (4): perf/core: Add aux_pause, aux_resume, aux_start_paused perf/x86/intel/pt: Add support for pause / resume perf tools: Add support for AUX area pause / resume coresight: Have a stab at support for pause / resume
arch/x86/events/intel/pt.c | 63 ++++++++++++++++++++- arch/x86/events/intel/pt.h | 4 ++ drivers/hwtracing/coresight/coresight-etm-perf.c | 29 ++++++++-- include/linux/perf_event.h | 15 +++++ include/uapi/linux/perf_event.h | 11 +++- kernel/events/core.c | 72 +++++++++++++++++++++++- kernel/events/internal.h | 1 + tools/include/uapi/linux/perf_event.h | 11 +++- tools/perf/util/auxtrace.c | 4 ++ tools/perf/util/evsel.c | 9 +++ tools/perf/util/evsel_config.h | 6 ++ tools/perf/util/parse-events.c | 33 +++++++++++ tools/perf/util/parse-events.h | 3 + tools/perf/util/parse-events.l | 3 + tools/perf/util/perf_event_attr_fprintf.c | 3 + 15 files changed, 255 insertions(+), 12 deletions(-)
Regards Adrian
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