This series aims to extend fprobe with list-style filters and a clear
entry/exist qualifier. Users can now specify a comma-separated symbol
list with ! exclusions, and use a spec-level suffix to select probe
type:

- funcA*, !funcAB, funcC -> entry probes
- funcA*, !funcAB, funcC:entry -> explicit entry
- funcA*, !funcAB, funcC:exit -> return/exit across the whole list

For compatibility, %return remains supported for single, literal
symbols. When a list or wildcard is used, an explicit [GROUP/EVENT is
required and autogeneration is disabled. Autogen names are kept for
single-symbol specs, with wildcard sanitization. For list/wildcard forms
we set ctx->funcname = NULL so BTF lookups are not attempted.

The series moves parsing to the parse path, documents the new syntax,
and adds selftests that accept valid list cases and reject empty tokens,
stray commas, and %return mixed with lists or wildcards. Selftests also
verify enable/disable flow and that entry+exit on the same set do not
double-count attached functions.

Help wanted: This is my first time contributing ftrace selftests. I
would appreciate comments and recommendations on test structure and
coverage.

Basic coverage is included, but this likely needs broader testing across
architectures. Feedback and additional test ideas are welcome.

Changes since v2:
- Introduce spec-level: :entry/:exit; reject %return with
  lists/wildcards
- Require explict [GROUP/]EVENT for list/wildcard; keep autogen only for
  single literal.
- Sanitize autogen names for single-symbol wildcards
- Set ctx->funcname = NULL for list/wildcard to bypass BTF
- Move list parsing out of __register_trace_fprobe() and into the parse
  path
- Update docs and tracefs README and add dynevent selftests for
  accept/reject and enable/disable flow

Link: 
https://lore.kernel.org/lkml/[email protected]/

Ryan Chung (5):
  docs: tracing: fprobe: document list filters and :entry/:exit
  tracing: fprobe: require explicit [GROUP/]EVENT for list/wildcard
  tracing: fprobe: support comma-separated symbols and :entry/:exit
  selftests/ftrace: dynevent: add reject cases for list/:entry/:exit
  selftests/ftrace: dynevent: add reject cases

 Documentation/trace/fprobetrace.rst           |  27 +-
 kernel/trace/trace.c                          |   3 +-
 kernel/trace/trace_fprobe.c                   | 247 ++++++++++++++----
 .../test.d/dynevent/add_remove_fprobe.tc      | 121 +++++++++
 .../test.d/dynevent/fprobe_syntax_errors.tc   |  13 +
 5 files changed, 349 insertions(+), 62 deletions(-)

-- 
2.43.0


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