perfetto: Dynamically create and remove trace event triggers

Using a persistent event trigger for rss_stat_throttled was
found to cause regression of 8% more CPU cycles in kswapd.

Have perfetto dynamically create these triggers when needed
and cleanup the trigger once the perfetto session no longer
needs it.

Triggers are created/removed when the associated trace
event is enabled/disabled by perfetto, so multiple sessions
with the same event trigger are inherently handled correctly
by the same ftrace_config_muxer logic for enabling/disabling
ftrace events.

The persistent rss_stat_throttled histogram trigger will be changed
to an as-needed trigger created by perfetto. So the existence of
this event trigger can no longer be used to check if the kernel
supports throttling rss_stat event.

Instead test creating a histogram trigger with division
arithmetic (needed for event throttling) on rss_stat_throttled.
Creating the trigger on rss_stat_throttled also implicitly checks
that the synthetic throttled event is present.

Test: adb push test/configs/rss_stat.cfg /data/local/tmp/
        && cf-adb shell 'cat /data/local/tmp/rss_stat.cfg |
	   perfetto --txt -c - -o /data/misc/perfetto-traces/trace
Bug: 236172293
Change-Id: I9e14d56bb442129ea85163e492e00382eb8d8994
Merged-In: I9e14d56bb442129ea85163e492e00382eb8d8994
Merged-In: Ifa50c9e08893c8494739747fe77ab1ceec5c0dfd
3 files changed
tree: 049210e71a2c5f3acd20be51f40e4c27f7e49b71
  1. .github/
  2. bazel/
  3. build_overrides/
  4. buildtools/
  5. debian/
  6. docs/
  7. examples/
  8. gn/
  9. include/
  10. infra/
  11. protos/
  12. python/
  13. src/
  14. test/
  15. tools/
  16. ui/
  17. .clang-format
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  19. .gitattributes
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  25. BUILD
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  28. CHANGELOG
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  30. DIR_METADATA
  31. heapprofd.rc
  32. LICENSE
  33. meson.build
  34. METADATA
  35. MODULE_LICENSE_APACHE2
  36. OWNERS
  37. perfetto.rc
  38. PerfettoIntegrationTests.xml
  39. PRESUBMIT.py
  40. README.chromium
  41. README.md
  42. TEST_MAPPING
  43. traced_perf.rc
  44. WORKSPACE
README.md

Perfetto - System profiling, app tracing and trace analysis

Perfetto is a production-grade open-source stack for performance instrumentation and trace analysis. It offers services and libraries and for recording system-level and app-level traces, native + java heap profiling, a library for analyzing traces using SQL and a web-based UI to visualize and explore multi-GB traces.

See https://perfetto.dev/docs or the /docs/ directory for documentation.