trace_processor: add all bits iterator

This CL adds an iterator implementation for all the bits of a bitvector.

We need this because we often want to iterate through the bits and make
changes as we iterate. This is inefficient if BitVector::Set is used
however, because the counts vector is constantly updated making the
whole algorithm O(n^2).

The new bitvector implementation instead defers updating counts until
the end of each block and only updates the next block's count. This
makes the algorithm O(n) instead.

We also add a base class for the iterator because we also want a
SetBitsIterator which will share much of the code. This common code has
been factored out into BaseIterator.

Bug: 137284957
Change-Id: Ie58cccca87a78e53a60e94006714c11983791613
8 files changed
tree: c99f8ed93a7d551529ee6f7f77c8d30fae7b47e1
  1. bazel/
  2. build_overrides/
  3. buildtools/
  4. debian/
  5. docs/
  6. gn/
  7. include/
  8. infra/
  9. protos/
  10. src/
  11. test/
  12. tools/
  13. ui/
  14. .clang-format
  15. .gitignore
  16. .gn
  17. .style.yapf
  18. Android.bp
  19. Android.bp.extras
  20. BUILD
  21. BUILD.extras
  22. BUILD.gn
  23. codereview.settings
  24. heapprofd.rc
  25. MODULE_LICENSE_APACHE2
  26. NOTICE
  27. OWNERS
  28. perfetto.rc
  29. PRESUBMIT.py
  30. README.chromium
  31. README.md
  32. TEST_MAPPING
  33. WORKSPACE
README.md

Perfetto - Performance instrumentation and tracing

Perfetto is an open-source project for performance instrumentation and tracing of Linux/Android/Chrome platforms and user-space apps.

See www.perfetto.dev for docs.

Bugs

  • For bugs affecting Android or the tracing internals use the internal bug tracker (go/perfetto-bugs).
  • For bugs affecting Chrome use http://crbug.com, Component:Speed>Tracing label:Perfetto.

Community

You can reach us on our Discord channel. If you prefer using IRC we have an experimental Discord <> IRC bridge synced with #perfetto-dev on Freenode.