[PATCH v2 0/6] Add a libdw addr2line implementation

[Ian Rogers <irogers@google.com>]

addr2line is a performance bottleneck in perf, add a libdw based
implementation that avoids forking addr2line and caches the decoded
debug information.

Allow the addr2line implementation to be picked via the configuration
file or --addr2line-style with `perf report`.

Test/fix that inline callchains are properly displayed by perf script.

v2: Fix bias issue with libdwfl functions. Use cu_walk_functions_at
    from perf's dwarf-aux to fully walk inline functions. Add testing
    that inlined functions are shown in the perf script srcline
    callchain information. Add configurability as to which addr2line
    style to use.

v1: https://lore.kernel.org/lkml/20251122093934.94971-1-irogers@google.com/

Ian Rogers (6):
  perf addr2line: Add a libdw implementation
  perf addr2line.c: Rename a2l_style to cmd_a2l_style
  perf srcline: Add configuration support for the addr2line style
  perf callchain: Fix srcline printing with inlines
  perf test workload: Add inlineloop test workload
  perf test: Test addr2line unwinding works with inline functions

 tools/perf/builtin-report.c                 |  10 ++
 tools/perf/tests/builtin-test.c             |   1 +
 tools/perf/tests/shell/addr2line_inlines.sh |  47 +++++++
 tools/perf/tests/tests.h                    |   1 +
 tools/perf/tests/workloads/Build            |   2 +
 tools/perf/tests/workloads/inlineloop.c     |  52 +++++++
 tools/perf/util/Build                       |   1 +
 tools/perf/util/addr2line.c                 |  20 +--
 tools/perf/util/config.c                    |   4 +
 tools/perf/util/dso.c                       |   2 +
 tools/perf/util/dso.h                       |  11 ++
 tools/perf/util/evsel_fprintf.c             |   8 +-
 tools/perf/util/libdw.c                     | 148 ++++++++++++++++++++
 tools/perf/util/libdw.h                     |  60 ++++++++
 tools/perf/util/srcline.c                   | 116 +++++++++++++--
 tools/perf/util/srcline.h                   |   3 +
 tools/perf/util/symbol_conf.h               |  10 ++
 17 files changed, 476 insertions(+), 20 deletions(-)
 create mode 100755 tools/perf/tests/shell/addr2line_inlines.sh
 create mode 100644 tools/perf/tests/workloads/inlineloop.c
 create mode 100644 tools/perf/util/libdw.c
 create mode 100644 tools/perf/util/libdw.h

-- 
2.52.0.457.g6b5491de43-goog