[PATCH V3 3/3] Documentation/osnoise: Add osnoise/options documentation

From: Daniel Bristot de Oliveira
Date: Fri Nov 25 2022 - 16:20:51 EST


Add the documentation about the osnoise/options file, the options,
and some additional explanation about the OSNOISE_WORKLOAD option.

Cc: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
---
Documentation/trace/osnoise-tracer.rst | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/Documentation/trace/osnoise-tracer.rst b/Documentation/trace/osnoise-tracer.rst
index 3c675ed82b27..0641781b00f5 100644
--- a/Documentation/trace/osnoise-tracer.rst
+++ b/Documentation/trace/osnoise-tracer.rst
@@ -92,8 +92,8 @@ Note that the example above shows a high number of HW noise samples.
The reason being is that this sample was taken on a virtual machine,
and the host interference is detected as a hardware interference.

-Tracer options
----------------------
+Tracer Configuration
+--------------------

The tracer has a set of options inside the osnoise directory, they are:

@@ -115,6 +115,22 @@ The tracer has a set of options inside the osnoise directory, they are:
NO_OSNOISE_WORKLOAD disables the OSNOISE_WORKLOAD option. The
special DEAFAULTS option resets all options to the default value.

+Tracer Options
+--------------
+
+The osnoise/options file exposes a set of on/off configuration options for
+the osnoise tracer. These options are:
+
+ - DEFAULTS: reset the options to the default value.
+ - OSNOISE_WORKLOAD: do not dispatch osnoise workload (see dedicated
+ section below).
+ - PANIC_ON_STOP: call panic() if the tracer stops. This option serves to
+ capture a vmcore.
+ - OSNOISE_PREEMPT_DISABLE: disable preemption while running the osnoise
+ workload, allowing only IRQ and hardware-related noise.
+ - OSNOISE_IRQ_DISABLE: disable IRQs while running the osnoise workload,
+ allowing only NMIs and hardware-related noise, like hwlat tracer.
+
Additional Tracing
------------------

--
2.32.0