On Mon, 28 Jul 2025 17:15:22 -0400 Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > From: Steven Rostedt <rostedt@xxxxxxxxxxx> > > Eprobes was added back in 5.15, but was never documented. It became a > "secret" interface even though it has been a topic of several > presentations. For some reason, when eprobes was added, documenting it > never became a priority, until now. > Thanks for the document! > Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> > --- > Documentation/trace/eprobes.rst | 268 ++++++++++++++++++++++++++++++++ > Documentation/trace/index.rst | 1 + > 2 files changed, 269 insertions(+) > create mode 100644 Documentation/trace/eprobes.rst > > diff --git a/Documentation/trace/eprobes.rst b/Documentation/trace/eprobes.rst > new file mode 100644 > index 000000000000..c7aa7c867e9e > --- /dev/null > +++ b/Documentation/trace/eprobes.rst BTW, can't you rename it as 'eprobetrace.rst' as same as others? I usually name the doc of "a probe feature which provides only in-kernel APIs" as '*probe.rst' and the doc of "a probe *event* feature which can controlled via tracefs interface" as '*probetrace.rst'. > @@ -0,0 +1,268 @@ > +.. SPDX-License-Identifier: GPL-2.0 > + > +===================== > +Eprobe - Event probes What about below title? Eprobe - Event-based Probe Tracing > +===================== > + > +:Author: Steven Rostedt <rostedt@xxxxxxxxxxx> > + > +- Written for v6.17 > + > +Overview > +======== > + > +Eprobes are dynamic events that are placed on existing events to eiter > +dereference a field that is a pointer, or simply to limit what fields get > +recorded in the trace event. > + > +Eprobes depend on kprobe events so to enable this feature, build your kernel > +with CONFIG_KPROBE_EVENTS=y. Is this correct? It seems that eprobe event only depends on event trigger (by implementation. Actually we should fix the kernel/trace/Kconfig.) https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git/tree/kernel/trace/trace_eprobe.c?h=trace-v6.16-rc5#n576 Thank you, -- Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
