[PATCH 0/3] perf probe: Boot time tracing support

From: Masami Hiramatsu
Date: Fri Jun 04 2021 - 12:28:19 EST


Hi,

Here is a series of patches to add boot-time tracing support to perf
probe command.
Recently, I tried to debug kernel boot process with boot-time tracing
and I found perf probe lacks some features for it.

[1/3] fixes perf probe to show probe definitions on __init functions.
Since __init functions are removed after boot (and those are not in
.text but .inittext section), perf's map object can not find them.
[2/3] is a code cleanup preparing for the next patch.
[3/3] adds --bootconfig option for showing the probe definitions in
the bootconfig format. This option can be used with -D (--definition)
option.

One todo is improving -F option. Since the -F option also using the
map object, it can not list up the __init function. Anyway, that may
not be important. Usually, the person who debugs kernel already know
the target function name, and can use "perf probe -L func" for
checking the function source code. (Note that perf probe -L doesn't
depend on map object)

Thank you,

---

Masami Hiramatsu (3):
perf/probe: Support probes on init functions for offline kernel
perf/probe: Cleanup synthesize_probe_trace_command
perf/probe: Add --bootconfig to output definition in bootconfig format


tools/perf/builtin-probe.c | 12 +++
tools/perf/util/probe-event.c | 167 +++++++++++++++++++++++++++++++----------
tools/perf/util/probe-event.h | 2
3 files changed, 141 insertions(+), 40 deletions(-)

--
Masami Hiramatsu (Linaro) <mhiramat@xxxxxxxxxx>