Re: [PATCH v5 v5 1/3] docs: tracing/fprobe: Document list filters and :entry/:exit
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2026-01-20 20:53:21
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linux-doc, linux-kselftest, lkml
On Sat, 17 Jan 2026 20:18:13 -0500 "Seokwoo Chung (Ryan)" [off-list ref] wrote:
Update fprobe event documentation to describe comma-separated symbol lists, exclusions, and explicit suffixes.
Usually, the documentation updates comes *after* the changes. -- Steve
quoted hunk ↗ jump to hunk
Signed-off-by: Seokwoo Chung (Ryan) <redacted> --- 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)