Extend the fprobe event interface to accept comma-separated symbol lists
with ! exclusion prefix, and :entry/:exit suffixes as an alternative to
%return.  Single-symbol probes retain full backward compatibility with
%return.

Example usage:
  f:mygroup/myevent vfs_read,!vfs_write,vfs_open:entry
  f:mygroup/myexit  vfs_read,vfs_open:exit

Changes since v5:
  - Fix missing closing brace in the empty-token check that caused a
    build error.
  - Remove redundant strchr/strstr checks for tracepoint validation;
    the character validation loop already rejects ',', ':', and '%'.
  - Add trace_probe_log_err() to the tracepoint character validation
    loop so users see what went wrong in tracefs/error_log (reviewer
    feedback from Masami Hiramatsu).
  - Remove unnecessary braces around single-statement if per kernel
    coding style (reviewer feedback).
  - Extract list parsing into parse_fprobe_list() to keep
    parse_fprobe_spec() focused (reviewer feedback).
  - New patch 2/4: add glob_match_comma_list() in kernel/trace/fprobe.c
    so register_fprobe() correctly handles comma-separated filter
    strings.  Without this, enabling a list-mode fprobe event failed
    with "Could not enable event" because glob_match() does not
    understand commas.
  - Reorder: documentation patch now comes after all code changes.
  - Updated selftest commit message to note that existing tests
    (add_remove_fprobe.tc, fprobe_syntax_errors.tc,
    add_remove_fprobe_repeat.tc) report UNSUPPORTED because their
    "requires" lines still check for the old %return syntax in README.
    Their requires lines need updating in a follow-up patch.

Tested in QEMU/KVM but I am not too confident if I configured correctly and
would like to ask for further testing. 

Seokwoo Chung (Ryan) (4):
  tracing/fprobe: Support comma-separated symbols and :entry/:exit
  fprobe: Support comma-separated filters in register_fprobe()
  docs: tracing/fprobe: Document list filters and :entry/:exit
  selftests/ftrace: Add accept cases for fprobe list syntax

 Documentation/trace/fprobetrace.rst           |  17 +-
 kernel/trace/fprobe.c                         |  30 ++-
 kernel/trace/trace.c                          |   3 +-
 kernel/trace/trace_fprobe.c                   | 219 ++++++++++++++----
 .../ftrace/test.d/dynevent/fprobe_list.tc     |  92 ++++++++
 5 files changed, 308 insertions(+), 53 deletions(-)
 create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/fprobe_list.tc

-- 
2.43.0