Re: [PATCH v5 v5 1/3] docs: tracing/fprobe: Document list filters and :entry/:exit
From: Seokwoo Chung
Date: Sun Jan 25 2026 - 15:23:36 EST
On Tue, Jan 20, 2026 at 03:53:40PM -0500, Steven Rostedt wrote:
> On Sat, 17 Jan 2026 20:18:13 -0500
> "Seokwoo Chung (Ryan)" <seokwoo.chung130@xxxxxxxxx> wrote:
>
> > Update fprobe event documentation to describe comma-separated symbol lists,
> > exclusions, and explicit suffixes.
>
> Usually, the documentation updates comes *after* the changes.
>
> -- Steve
>
Thanks for the comment. As you noticed, I sent another patch since I forgot to
put log. That said, please let me know if you want me to continue on this
series. My apologies on the ordering. I noted after Masami mentioned but I
misordered when sending. Thank you.
Best regards,
Ryan Chung
> >
> > Signed-off-by: Seokwoo Chung (Ryan) <seokwoo.chung130@xxxxxxxxx>
> > ---
> > Documentation/trace/fprobetrace.rst | 17 ++++++++++++++---
> > 1 file changed, 14 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
> > index b4c2ca3d02c1..bbcfd57f0005 100644
> > --- a/Documentation/trace/fprobetrace.rst
> > +++ b/Documentation/trace/fprobetrace.rst
> > @@ -25,14 +25,18 @@ Synopsis of fprobe-events
> > -------------------------
> > ::
> >
> > - f[:[GRP1/][EVENT1]] SYM [FETCHARGS] : Probe on function entry
> > - f[MAXACTIVE][:[GRP1/][EVENT1]] SYM%return [FETCHARGS] : Probe on function exit
> > + f[:[GRP1/][EVENT1]] SYM[%return] [FETCHARGS] : Single function
> > + f[:[GRP1/][EVENT1]] SYM[,[!]SYM[,...]][:entry|:exit] [FETCHARGS] :Multiple
> > + function
> > t[:[GRP2/][EVENT2]] TRACEPOINT [FETCHARGS] : Probe on tracepoint
> >
> > GRP1 : Group name for fprobe. If omitted, use "fprobes" for it.
> > GRP2 : Group name for tprobe. If omitted, use "tracepoints" for it.
> > EVENT1 : Event name for fprobe. If omitted, the event name is
> > - "SYM__entry" or "SYM__exit".
> > + - For a single literal symbol, the event name is
> > + "SYM__entry" or "SYM__exit".
> > + - For a *list or any wildcard*, an explicit [GRP1/][EVENT1] is
> > + required; otherwise the parser rejects it.
> > EVENT2 : Event name for tprobe. If omitted, the event name is
> > the same as "TRACEPOINT", but if the "TRACEPOINT" starts
> > with a digit character, "_TRACEPOINT" is used.
> > @@ -40,6 +44,13 @@ Synopsis of fprobe-events
> > can be probed simultaneously, or 0 for the default value
> > as defined in Documentation/trace/fprobe.rst
> >
> > + SYM : Function name or comma-separated list of symbols.
> > + - SYM prefixed with "!" are exclusions.
> > + - ":entry" suffix means it probes entry of given symbols
> > + (default)
> > + - ":exit" suffix means it probes exit of given symbols.
> > + - "%return" suffix means it probes exit of SYM (single
> > + symbol).
> > FETCHARGS : Arguments. Each probe can have up to 128 args.
> > ARG : Fetch "ARG" function argument using BTF (only for function
> > entry or tracepoint.) (\*1)
>