RTOSBench for Zephyr

This repository contains a Zephyr application that executes benchmarks from RTOSBench.

Getting Started

First set up your Zephyr working environment according to the instructions provided in Zephyr's Getting Started Guide. Then you can clone the project using Zephyr's metatool west. The following shell commands initialize the project in a workspace directory named my-workspace:

west init -m https://github.com/methodpark/zephyr-rtosbench my-workspace
cd my-workspace
west update

Building and Running

The test cases can be build by running west build -b $BOARD -s app. Here $BOARD has to be replaced with the target board. After building, the respective test case can be executed on hardware by running west flash or west build -t run. Results can be read by attaching to the board's serial output (e.g. cat /dev/ttyACM0).

Changing the Test Case

By default, the test case located under app/lib/rtosbench/tests/context-switch/round_robin.c is executed. This can be changed by providing the build command with another value for the variable RTOS_BENCH_TEST_CASE. In order to execute the test case under app/lib/rtosbench/tests/mutex/mutex.c, for example, define RTOS_BENCH_TEST_CASE=mutex/mutex like this:

west build -b $BOARD -s app -- -DRTOS_BENCH_TEST_CASE=mutex/mutex

Changing the Test Configuration

RTOSBench outputs average, minimum and maximum measured values by default. It is also possible to retrieve the result of each iterations instead. The west project exposes this functionality via the CMake parameter VERBOSE_RESULTS. It can be enabled during the build process in the following way:

west build -b $BOARD -s app -- -DVERBOSE_RESULTS=1

Similarily, it is also possible to configure the benchmark's number of iterations, that is, how many times a test is executed. This is controlled via the CMake variable ITERATIONS. To change it run west build like this:

west build -b $BOARD -s app -- -DITERATIONS=10000

The example above runs a test 10000 times.

Tracing

Zephyr offers builtin support for tracing in various formats. The repository contains two configuration files that activate all necessary KConfig options for either SEGGER SystemView or via UART using the Common Tracing Format (CTF).

The benchmark code automatically inserts a delay of 5 seconds before the benchmark actually starts. This way you should be able to start capturing tracing data before the test case is executed.

You can build a test case with tracing support for SEGGER SystemView by calling west in the following way:

west build -b $BOARD -s app -- -DOVERLAY_CONFIG='prj_sysview.conf'

If your board does not have support for SEGGER SystemView, you can trace using UART with the following command line:

west build -b $BOARD -s app -- -DOVERLAY_CONFIG='prj_uart_ctf.conf'

Since the tracing data is transmitted via the serial console, this configuration suppresses any console output from the benchmark. In order actually capture the tracing output, you have to execute the capture script provided by Zephyr under zephyr/scripts/trace_capture_uart.py. A typical command line would look like this:

./scripts/tracing/trace_capture_uart.py -d /dev/ttyACM0 -b 115200 -o output_file

Follow the instructions from Zephyr's Documentation to visualise the data in e.g. TraceCompass.