[PATCH] Basic Support for Trace Compass

Thu Aug 8 12:03:12 UTC 2019

---
 images/user/event-recording-trace.png  | Bin 0 -> 9573 bytes
 images/user/event-recording-trace.puml |  12 +++
 user/tracing/eventrecording.rst        | 117 ++++++++++++++++++++++++-
 3 files changed, 128 insertions(+), 1 deletion(-)
 create mode 100644 images/user/event-recording-trace.png
 create mode 100644 images/user/event-recording-trace.puml

diff --git a/images/user/event-recording-trace.png b/images/user/event-recording-trace.png
new file mode 100644
index 0000000000000000000000000000000000000000..eeb28b052bc42f0beb6c8cee4928c1e1161c570e
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diff --git a/images/user/event-recording-trace.puml b/images/user/event-recording-trace.puml
new file mode 100644
index 0000000..6705748
--- /dev/null
+++ b/images/user/event-recording-trace.puml
@@ -0,0 +1,12 @@
+ at startuml
+
+rectangle Host
+rectangle "Target/QEMU Target" as target
+rectangle "Trace Compass" as tracecompass
+rectangle "Babeltrace" as babeltrace
+Host --> target : Connecting
+target --> Host : RTEMS Trace Data
+Host --> tracecompass : CTF
+Host --> babeltrace : CTF
+
+ at enduml
\ No newline at end of file
diff --git a/user/tracing/eventrecording.rst b/user/tracing/eventrecording.rst
index d799774..554e5bc 100644
--- a/user/tracing/eventrecording.rst
+++ b/user/tracing/eventrecording.rst
@@ -6,7 +6,7 @@
 .. _EventRecording:
 
 Event Recording
-===============
+***************
 
 The `event recording` support focuses on the recording of high frequency
 events such as
@@ -56,3 +56,118 @@ started by :c:func:`rtems_record_start_server` via a TCP connection.
 
 On the host computer you may use the command line tool :file:`rtems-record` to
 get recorded events from the record server running on the target system.
+
+.. _tracecompass:
+
+Trace Compass
+=============
+
+`Trace Compass <https://www.eclipse.org/tracecompass/>`_ is a tool to analyse 
+and display trace data graphically. Trace data can be gathered from  RTEMS 
+applications via various means, for example:
+
+- :ref:`RTEMS Trace Linker <TraceLinker>`
+- :ref:`RTEMS Capture Engine <CaptureEngine>`
+- :ref:`RTEMS Event Recording <EventRecording>`
+
+Event Recording infrastructure is used to analyse and display some basic 
+information. The basic information is defined by the Linux kernel trace 
+support (lttng) and includes CPU Usage, IRQ Analysis(IRQ Statistics, 
+IRQ Table etc.), Linux Kernel(Control Flow, Resources etc.)
+
+Advanced support for Trace Compass includes dynamic memory traces, stack usage,
+network packet flow, etc.
+
+Currently the event recording infrastructure lacks the generation of trace
+data in CTF format.
+
+This scheme of tracing goes through the flow of events described in a subsequent
+flowchart. This requires the environment setup of 
+`rtems-libbsd <https://github.com/RTEMS/rtems-libbsd>`_  and 
+`rtems-tools <https://github.com/RTEMS/rtems-tools>`_:
+
+Step 1: The QEMU simulator is used to run a LibBSD based application and connect
+it to a virtual network on host. This requires to create a TAP virtual Ethernet
+interface for this. The QEMU command line is used for board support package, e.g
+the arm/xilinx_zynq_a9_qemu BSP etc. The host can be connected to target via 
+telnet.
+
+Step 2: On the host computer the command line tool rtems-record can be used to
+get recorded events from the record server running on the target system. 
+Recorded events can be sent to a host computer with a very simple record server
+started by rtems_record_start_server() via a TCP connection.
+
+Step 3: The trace data received at host from QEMU target is converted into CTF.
+Since, Babeltrace and Trace Compass are two compatible software which can read
+and write CTF. The converted CTF ca be passed to any of these softwares.
+
+.. figure:: ../../images/user/event-recording-trace.png
+  :align: center
+  :width: 75%
+
+RTEMS Trace Item Generation Example
+===================================
+
+Step 1: Clone the repositories 
+`rtems-libbsd <https://github.com/rmeena840/rtems-libbsd/tree/ravindra-rtems>`_  
+and 
+`rtems-tools <https://github.com/rmeena840/rtems-tools/tree/ravindra-rtems>`_.
+
+Step 2: The Qemu command line varies by board support package, here is an
+example for the arm/xilinx_zynq_a9_qemu BSP:
+
+.. code-block:: none
+
+  cd rtems-libbsd
+
+  qemu-system-arm -serial null -serial mon:stdio -nographic \
+  -M xilinx-zynq-a9 -m 256M \
+  -net tap,ifname=qtap,script=no,downscript=no \
+  -net nic,model=cadence_gem,macaddr=0e:b0:ba:5e:ba:12 \
+  -kernel build/arm-rtems5-xilinx_zynq_a9_qemu-default/media01.exe
+
+Step 3: This requires to TAP virtual Ethernet interface for this:
+
+.. code-block:: none
+
+  sudo tunctl -p -t qtap -u $(whoami)
+  sudo ip link set dev qtap up
+  sudo ip addr add 169.254.1.1/16 dev qtap
+
+After some seconds it will acquire a IPv4 link-local address, e.g.
+
+.. code-block:: none
+  
+  info: cgem0: probing for an IPv4LL address
+  debug: cgem0: checking for 169.254.XXX.XXX
+
+Use telnet command to connect host to target.
+
+.. code-block:: none
+  
+  telnet 169.254.XXX.XXX
+
+Step 4: After successfully connected to the target, we can get event records
+item  from QEMU target text format by using the following commands:
+
+.. code-block:: none
+
+  cd rtems-tools
+  ./build/misc/rtems-record -H 169.254.XXX.XXX -p 1234 | head
+
+The received trace generated on host will look like this:
+
+.. code-block:: none
+
+  0.003629099:0:THREAD_SWITCH_OUT:9010001
+  0.003629099:0:THREAD_STACK_CURRENT:e68
+  0.003629099:0:THREAD_SWITCH_IN:a010005
+  0.003847169:0:THREAD_SWITCH_OUT:a010005
+  0.003847169:0:THREAD_STACK_CURRENT:7ea8
+  0.003847169:0:THREAD_SWITCH_IN:9010001
+  0.004627569:0:THREAD_SWITCH_OUT:9010001
+  0.004627569:0:THREAD_STACK_CURRENT:e68
+  0.004627569:0:THREAD_SWITCH_IN:a010005
+  0.004912869:0:THREAD_SWITCH_OUT:a010005
+
+The received event records items is not in CTF format.
-- 
2.21.0

